Hardness. Medical search

The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.

Synthetic resins, containing an inert filler, that are widely used in dentistry.

Light sources used to activate polymerization of light-cured DENTAL CEMENTS and DENTAL RESINS. Degree of cure and bond strength depends on exposure time, wavelength, and intensity of the curing light.

Materials used in the production of dental bases, restorations, impressions, prostheses, etc.

Characteristics or attributes of the outer boundaries of objects, including molecules.

The hardening or polymerization of bonding agents (DENTAL CEMENTS) via chemical reactions, usually involving two components. This type of dental bonding uses a self-cure or dual-cure system.

Solid dosage forms, of varying weight, size, and shape, which may be molded or compressed, and which contain a medicinal substance in pure or diluted form. (Dorland, 28th ed)

A family of nonmetallic, generally electronegative, elements that form group 17 (formerly group VIIa) of the periodic table.

The nonexpendable items used by the dentist or dental staff in the performance of professional duties. (From Boucher's Clinical Dental Terminology, 4th ed, p106)

The use of a layer of tooth-colored material, usually porcelain or acrylic resin, applied to the surface of natural teeth, crowns, or pontics by fusion, cementation, or mechanical retention.

Creation of a smooth and glossy surface finish on a denture or amalgam.

The field of dentistry involved in procedures for designing and constructing dental appliances. It includes also the application of any technology to the field of dentistry.

The process of producing a form or impression made of metal or plaster using a mold.

The description and measurement of the various factors that produce physical stress upon dental restorations, prostheses, or appliances, materials associated with them, or the natural oral structures.

Dental cements composed either of polymethyl methacrylate or dimethacrylate, produced by mixing an acrylic monomer liquid with acrylic polymers and mineral fillers. The cement is insoluble in water and is thus resistant to fluids in the mouth, but is also irritating to the dental pulp. It is used chiefly as a luting agent for fabricated and temporary restorations. (Jablonski's Dictionary of Dentistry, 1992, p159)

The quality or state of being able to be bent or creased repeatedly. (From Webster, 3d ed)

Polymers of high molecular weight which at some stage are capable of being molded and then harden to form useful components.

Silicon polymers that contain alternate silicon and oxygen atoms in linear or cyclic molecular structures.

A type of porcelain used in dental restorations, either jacket crowns or inlays, artificial teeth, or metal-ceramic crowns. It is essentially a mixture of particles of feldspar and quartz, the feldspar melting first and providing a glass matrix for the quartz. Dental porcelain is produced by mixing ceramic powder (a mixture of quartz, kaolin, pigments, opacifiers, a suitable flux, and other substances) with distilled water. (From Jablonski's Dictionary of Dentistry, 1992)

Restorations of metal, porcelain, or plastic made to fit a cavity preparation, then cemented into the tooth. Onlays are restorations which fit into cavity preparations and overlay the occlusal surface of a tooth or teeth. Onlays are retained by frictional or mechanical factors.

Organic-inorganic hybrid polymers developed primarily for DENTAL RESTORATION. They typically contain a defined mixture of ORGANOSILICON COMPOUNDS; CERAMICS; and organic POLYMERS.

Numerical expression indicating the measure of stiffness in a material. It is defined by the ratio of stress in a unit area of substance to the resulting deformation (strain). This allows the behavior of a material under load (such as bone) to be calculated.

A hard thin translucent layer of calcified substance which envelops and protects the dentin of the crown of the tooth. It is the hardest substance in the body and is almost entirely composed of calcium salts. Under the microscope, it is composed of thin rods (enamel prisms) held together by cementing substance, and surrounded by an enamel sheath. (From Jablonski, Dictionary of Dentistry, 1992, p286)

Chemical reaction in which monomeric components are combined to form POLYMERS (e.g., POLYMETHYLMETHACRYLATE).

Usually inert substances added to a prescription in order to provide suitable consistency to the dosage form. These include binders, matrix, base or diluent in pills, tablets, creams, salves, etc.

Beverages consumed as stimulants and tonics. They usually contain a combination of CAFFEINE with other substances such as herbal supplements; VITAMINS; AMINO ACIDS; and sugar or sugar derivatives.

Poly-2-methylpropenoic acids. Used in the manufacture of methacrylate resins and plastics in the form of pellets and granules, as absorbent for biological materials and as filters; also as biological membranes and as hydrogens. Synonyms: methylacrylate polymer; poly(methylacrylate); acrylic acid methyl ester polymer.

A restoration designed to remain in service for not less than 20 to 30 years, usually made of gold casting, cohesive gold, or amalgam. (Jablonski, Dictionary of Dentistry, 1992)

A prosthetic appliance for the replacement of areas of the maxilla, mandible, and face, missing as a result of deformity, disease, injury, or surgery. When the prosthesis replaces portions of the mandible only, it is referred to as MANDIBULAR PROSTHESIS.

A fabricated tooth substituting for a natural tooth in a prosthesis. It is usually made of porcelain or plastic.

Occlusal wear of the surfaces of restorations and surface wear of dentures.

Chemistry dealing with the composition and preparation of agents having PHARMACOLOGIC ACTIONS or diagnostic use.

Inorganic compounds that contain carbon as an integral part of the molecule but are not derived from hydrocarbons.

Material from which the casting mold is made in the fabrication of gold or cobalt-chromium castings. (Boucher's Clinical Dental Terminology, 4th ed, p168)

A dark-gray, metallic element of widespread distribution but occurring in small amounts; atomic number, 22; atomic weight, 47.90; symbol, Ti; specific gravity, 4.5; used for fixation of fractures. (Dorland, 28th ed)

Products made by baking or firing nonmetallic minerals (clay and similar materials). In making dental restorations or parts of restorations the material is fused porcelain. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed & Boucher's Clinical Dental Terminology, 4th ed)

The act and process of chewing and grinding food in the mouth.

The maximum compression a material can withstand without failure. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p427)

A partial denture intended for short-term use in a temporary or emergency situation.

Acrylic acids or acrylates which are substituted in the C-2 position with a methyl group.

Coloring, shading, or tinting of prosthetic components, devices, and materials.

Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.

Methylester of cellulose. Methylcellulose is used as an emulsifying and suspending agent in cosmetics, pharmaceutics and the chemical industry. It is used therapeutically as a bulk laxative.

A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

Scanning microscopy in which a very sharp probe is employed in close proximity to a surface, exploiting a particular surface-related property. When this property is local topography, the method is atomic force microscopy (MICROSCOPY, ATOMIC FORCE), and when it is local conductivity, the method is scanning tunneling microscopy (MICROSCOPY, SCANNING TUNNELING).

The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.

Resistance and recovery from distortion of shape.

Materials that have a limited and usually variable electrical conductivity. They are particularly useful for the production of solid-state electronic devices.

Substances made up of an aggregation of small particles, as that obtained by grinding or trituration of a solid drug. In pharmacy it is a form in which substances are administered. (From Dorland, 28th ed)

Diamond. A crystalline form of carbon that occurs as hard, colorless or tinted isomeric crystals. It is used as a precious stone, for cutting glass, and as bearings for delicate mechanisms. (From Grant & Hackh's Chemical Dictionary, 5th ed)

The preparation, mixing, and assembling of a drug. (From Remington, The Science and Practice of Pharmacy, 19th ed, p1814)

A change of a substance from one form or state to another.

A tooth's loss of minerals, such as calcium in hydroxyapatite from the tooth matrix, caused by acidic exposure. An example of the occurrence of demineralization is in the formation of dental caries.

A polyvinyl polymer of variable molecular weight; used as suspending and dispersing agent and vehicle for pharmaceuticals; also used as blood volume expander.

Zirconium. A rather rare metallic element, atomic number 40, atomic weight 91.22, symbol Zr. (From Dorland, 28th ed)

The placing of a body or a part thereof into a liquid.

The reaction product of bisphenol A and glycidyl methacrylate that undergoes polymerization when exposed to ultraviolet light or mixed with a catalyst. It is used as a bond implant material and as the resin component of dental sealants and composite restorative materials.

Polymerized methyl methacrylate monomers which are used as sheets, moulding, extrusion powders, surface coating resins, emulsion polymers, fibers, inks, and films (From International Labor Organization, 1983). This material is also used in tooth implants, bone cements, and hard corneal contact lenses.

Compounds similar to hydrocarbons in which a tetravalent silicon atom replaces the carbon atom. They are very reactive, ignite in air, and form useful derivatives.

A polymer obtained by reacting polyacrylic acid with a special anion-leachable glass (alumino-silicate). The resulting cement is more durable and tougher than others in that the materials comprising the polymer backbone do not leach out.

Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)

Nanometer-scale composite structures composed of organic molecules intimately incorporated with inorganic molecules. (Glossary of Biotechnology and Nanobiotechology Terms, 4th ed)

Highly keratinized processes that are sharp and curved, or flat with pointed margins. They are found especially at the end of the limbs in certain animals.

The maximum stress a material subjected to a stretching load can withstand without tearing. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p2001)

The process of keeping pharmaceutical products in an appropriate location.

Identification and measurement of ELEMENTS and their location based on the fact that X-RAYS emitted by an element excited by an electron beam have a wavelength characteristic of that element and an intensity related to its concentration. It is performed with an electron microscope fitted with an x-ray spectrometer, in scanning or transmission mode.

A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.

The fusion of ceramics (porcelain) to an alloy of two or more metals for use in restorative and prosthodontic dentistry. Examples of metal alloys employed include cobalt-chromium, gold-palladium, gold-platinum-palladium, and nickel-based alloys.

Alloys that contain a high percentage of gold. They are used in restorative or prosthetic dentistry.

The properties and processes of materials that affect their behavior under force.

The hard portion of the tooth surrounding the pulp, covered by enamel on the crown and cementum on the root, which is harder and denser than bone but softer than enamel, and is thus readily abraded when left unprotected. (From Jablonski, Dictionary of Dentistry, 1992)

A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.

Tablets coated with material that delays release of the medication until after they leave the stomach. (Dorland, 28th ed)

Carbonic acid calcium salt (CaCO3). An odorless, tasteless powder or crystal that occurs in nature. It is used therapeutically as a phosphate buffer in hemodialysis patients and as a calcium supplement.

The constricted part of the tooth at the junction of the crown and root or roots. It is often referred to as the cementoenamel junction (CEJ), the line at which the cementum covering the root of a tooth and the enamel of the tooth meet. (Jablonski, Dictionary of Dentistry, 1992, p530, p433)

That portion of the electromagnetic spectrum from the UHF (ultrahigh frequency) radio waves and extending into the INFRARED RAYS frequencies.

The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).

Any preparations used for cleansing teeth; they usually contain an abrasive, detergent, binder and flavoring agent and may exist in the form of liquid, paste or powder; may also contain medicaments and caries preventives.

Compounds that provide LUBRICATION between surfaces in order to reduce FRICTION.

A class of statistical methods applicable to a large set of probability distributions used to test for correlation, location, independence, etc. In most nonparametric statistical tests, the original scores or observations are replaced by another variable containing less information. An important class of nonparametric tests employs the ordinal properties of the data. Another class of tests uses information about whether an observation is above or below some fixed value such as the median, and a third class is based on the frequency of the occurrence of runs in the data. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1284; Corsini, Concise Encyclopedia of Psychology, 1987, p764-5)

Means or process of supplying water (as for a community) usually including reservoirs, tunnels, and pipelines and often the watershed from which the water is ultimately drawn. (Webster, 3d ed)

Dosage forms of a drug that act over a period of time by controlled-release processes or technology.

Technique by which phase transitions of chemical reactions can be followed by observation of the heat absorbed or liberated.

Material applied to the tissue side of a denture to provide a soft lining to the parts of a denture coming in contact with soft tissue. It cushions contact of the denture with the tissues.

The methyl esters of methacrylic acid that polymerize easily and are used as tissue cements, dental materials, and absorbent for biological substances.

A solution used for irrigating the mouth in xerostomia and as a substitute for saliva.

The application of scientific knowledge or technology to pharmacy and the pharmaceutical industry. It includes methods, techniques, and instrumentation in the manufacture, preparation, compounding, dispensing, packaging, and storing of drugs and other preparations used in diagnostic and determinative procedures, and in the treatment of patients.

A cellulose derivative which is a beta-(1,4)-D-glucopyranose polymer. It is used as a bulk laxative and as an emulsifier and thickener in cosmetics and pharmaceuticals and as a stabilizer for reagents.

A calcium salt that is used for a variety of purposes including: building materials, as a desiccant, in dentistry as an impression material, cast, or die, and in medicine for immobilizing casts and as a tablet excipient. It exists in various forms and states of hydration. Plaster of Paris is a mixture of powdered and heat-treated gypsum.

A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions for use in restorative or prosthetic dentistry.

Therapeutic technique for replacement of minerals in partially decalcified teeth.

The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.

Drinkable liquids combined with or impregnated with carbon dioxide.

Bony structure of the mouth that holds the teeth. It consists of the MANDIBLE and the MAXILLA.

A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].

Silicone polymers which consist of silicon atoms substituted with methyl groups and linked by oxygen atoms. They comprise a series of biocompatible materials used as liquids, gels or solids; as film for artificial membranes, gels for implants, and liquids for drug vehicles; and as antifoaming agents.

Condition of having pores or open spaces. This often refers to bones, bone implants, or bone cements, but can refer to the porous state of any solid substance.

A plant genus of the family ASTERACEAE. Arctiin (LIGNANS) is in the seed.

Elements of limited time intervals, contributing to particular results or situations.

A generic term for all substances having the properties of stretching under tension, high tensile strength, retracting rapidly, and recovering their original dimensions fully. They are generally POLYMERS.

A partial denture attached to prepared natural teeth, roots, or implants by cementation.

Substances used to create an impression, or negative reproduction, of the teeth and dental arches. These materials include dental plasters and cements, metallic oxide pastes, silicone base materials, or elastomeric materials.

A masticatory muscle whose action is closing the jaws; its posterior portion retracts the mandible.

Magnesium oxide (MgO). An inorganic compound that occurs in nature as the mineral periclase. In aqueous media combines quickly with water to form magnesium hydroxide. It is used as an antacid and mild laxative and has many nonmedicinal uses.

The spectrometric analysis of fluorescent X-RAYS, i.e. X-rays emitted after bombarding matter with high energy particles such as PROTONS; ELECTRONS; or higher energy X-rays. Identification of ELEMENTS by this technique is based on the specific type of X-rays that are emitted which are characteristic of the specific elements in the material being analyzed. The characteristic X-rays are distinguished and/or quantified by either wavelength dispersive or energy dispersive methods.

The upper part of the tooth, which joins the lower part of the tooth (TOOTH ROOT) at the cervix (TOOTH CERVIX) at a line called the cementoenamel junction. The entire surface of the crown is covered with enamel which is thicker at the extremity and becomes progressively thinner toward the cervix. (From Jablonski, Dictionary of Dentistry, 1992, p216)

The part of a denture that overlies the soft tissue and supports the supplied teeth and is supported in turn by abutment teeth or the residual alveolar ridge. It is usually made of resins or metal or their combination.

Inorganic compounds that contain potassium as an integral part of the molecule.

Rendering pathogens harmless through the use of heat, antiseptics, antibacterial agents, etc.

A masticatory muscle whose action is closing the jaws.

The degree of approximation or fit of filling material or dental prosthetic to the tooth surface. A close marginal adaptation and seal at the interface is important for successful dental restorations.

That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.

The joining of pieces of metal through the use of an alloy which has a lower melting point, usually at least 100 degrees Celsius below the fusion temperature of the parts being soldered. In dentistry, soldering is used for joining components of a dental appliance, as in assembling a bridge, joining metals to orthodontic bands, or adding to the bulk of certain structures, such as the establishment of proper contact areas on inlays and crowns with adjacent teeth. (Illustrated Dictionary of Dentistry, 1982)

A property of the surface of an object that makes it stick to another surface.

The use of a chemical oxidizing agent to whiten TEETH. In some procedures the oxidation process is activated by the use of heat or light.

An autosomal dominant disorder of tooth development characterized by opalescent dentin resulting in discoloration of the teeth. The dentin develops poorly with low mineral content while the pulp canal is obliterated.

Sodium or potassium salts of long chain fatty acids. These detergent substances are obtained by boiling natural oils or fats with caustic alkali. Sodium soaps are harder and are used as topical anti-infectives and vehicles in pills and liniments; potassium soaps are soft, used as vehicles for ointments and also as topical antimicrobials.

A polysaccharide with glucose units linked as in CELLOBIOSE. It is the chief constituent of plant fibers, cotton being the purest natural form of the substance. As a raw material, it forms the basis for many derivatives used in chromatography, ion exchange materials, explosives manufacturing, and pharmaceutical preparations.

An operation in which carious material is removed from teeth and biomechanically correct forms are established in the teeth to receive and retain restorations. A constant requirement is provision for prevention of failure of the restoration through recurrence of decay or inadequate resistance to applied stresses. (Boucher's Clinical Dental Terminology, 4th ed, p239-40)

Substances used to bond COMPOSITE RESINS to DENTAL ENAMEL and DENTIN. These bonding or luting agents are used in restorative dentistry, ROOT CANAL THERAPY; PROSTHODONTICS; and ORTHODONTICS.

The force applied by the masticatory muscles in dental occlusion.

A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions.

An oxide of aluminum, occurring in nature as various minerals such as bauxite, corundum, etc. It is used as an adsorbent, desiccating agent, and catalyst, and in the manufacture of dental cements and refractories.

Solutions for rinsing the mouth, possessing cleansing, germicidal, or palliative properties. (From Boucher's Clinical Dental Terminology, 4th ed)

The quality or state of being wettable or the degree to which something can be wet. This is also the ability of any solid surface to be wetted when in contact with a liquid whose surface tension is reduced so that the liquid spreads over the surface of the solid.

Cements that act through infiltration and polymerization within the dentinal matrix and are used for dental restoration. They can be adhesive resins themselves, adhesion-promoting monomers, or polymerization initiators that act in concert with other agents to form a dentin-bonding system.

The gradual destruction of a metal or alloy due to oxidation or action of a chemical agent. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

A genus of gram negative, aerobic, rod-shaped bacteria found in soil, plants, and marine mud.

The plan, delineation, and location of actual structural elements of dentures. The design can relate to retainers, stress-breakers, occlusal rests, flanges, framework, lingual or palatal bars, reciprocal arms, etc.

Any of a group of polysaccharides of the general formula (C6-H10-O5)n, composed of a long-chain polymer of glucose in the form of amylose and amylopectin. It is the chief storage form of energy reserve (carbohydrates) in plants.

Specific alloys not less than 85% chromium and nickel or cobalt, with traces of either nickel or cobalt, molybdenum, and other substances. They are used in partial dentures, orthopedic implants, etc.

Presence of warmth or heat or a temperature notably higher than an accustomed norm.

The elaboration of dental enamel by ameloblasts, beginning with its participation in the formation of the dentino-enamel junction to the production of the matrix for the enamel prisms and interprismatic substance. (Jablonski, Dictionary of Dentistry, 1992).

A semisynthetic cephalosporin antibiotic with antimicrobial activity similar to that of CEPHALORIDINE or CEPHALOTHIN, but somewhat less potent. It is effective against both gram-positive and gram-negative organisms.

Relating to the size of solids.

It is used as an oxidizing and bleaching agent and as a disinfectant. (From Grant & Hackh's Chemical Dictionary, 5th ed)

Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.

A noble gas with the atomic symbol Xe, atomic number 54, and atomic weight 131.30. It is found in the earth's atmosphere and has been used as an anesthetic.

Completed forms of the pharmaceutical preparation in which prescribed doses of medication are included. They are designed to resist action by gastric fluids, prevent vomiting and nausea, reduce or alleviate the undesirable taste and smells associated with oral administration, achieve a high concentration of drug at target site, or produce a delayed or long-acting drug effect.

The properties, processes, and behavior of biological systems under the action of mechanical forces.

Biocompatible materials usually used in dental and bone implants that enhance biologic fixation, thereby increasing the bond strength between the coated material and bone, and minimize possible biological effects that may result from the implant itself.

A quantitative prediction of the biological, ecotoxicological or pharmaceutical activity of a molecule. It is based upon structure and activity information gathered from a series of similar compounds.

A prosthetic restoration that reproduces the entire surface anatomy of the visible natural crown of a tooth. It may be partial (covering three or more surfaces of a tooth) or complete (covering all surfaces). It is made of gold or other metal, porcelain, or resin.

The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)

A test to determine the relative hardness of a metal, mineral, or other material according to one of several scales, such as Brinell, Mohs, Rockwell, Vickers, or Shore. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

A plant genus of the family POACEAE that is the source of EDIBLE GRAIN. A hybrid with rye (SECALE CEREALE) is called TRITICALE. The seed is ground into FLOUR and used to make BREAD, and is the source of WHEAT GERM AGGLUTININS.

The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.

An alkaloid from Hydrastis canadensis L., Berberidaceae. It is also found in many other plants. It is relatively toxic parenterally, but has been used orally for various parasitic and fungal infections and as antidiarrheal.

One of a set of bone-like structures in the mouth used for biting and chewing.

The encapsulated embryos of flowering plants. They are used as is or for animal feed because of the high content of concentrated nutrients like starches, proteins, and fats. Rapeseed, cottonseed, and sunflower seed are also produced for the oils (fats) they yield.

Inorganic salts of hydrofluoric acid, HF, in which the fluorine atom is in the -1 oxidation state. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) Sodium and stannous salts are commonly used in dentifrices.

A measure of the amount of WATER VAPOR in the air.

Substances that inhibit or arrest DENTAL CARIES formation. (Boucher's Clinical Dental Terminology, 4th ed)

An adhesion procedure for orthodontic attachments, such as plastic DENTAL CROWNS. This process usually includes the application of an adhesive material (DENTAL CEMENTS) and letting it harden in-place by light or chemical curing.

The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.

Non-invasive imaging methods based on the mechanical response of an object to a vibrational or impulsive force. It is used for determining the viscoelastic properties of tissue, and thereby differentiating soft from hard inclusions in tissue such as microcalcifications, and some cancer lesions. Most techniques use ultrasound to create the images - eliciting the response with an ultrasonic radiation force and/or recording displacements of the tissue by Doppler ultrasonography.

Localized destruction of the tooth surface initiated by decalcification of the enamel followed by enzymatic lysis of organic structures and leading to cavity formation. If left unchecked, the cavity may penetrate the enamel and dentin and reach the pulp.

Liquids that are suitable for drinking. (From Merriam Webster Collegiate Dictionary, 10th ed)

Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light.

A disaccharide of GLUCOSE and GALACTOSE in human and cow milk. It is used in pharmacy for tablets, in medicine as a nutrient, and in industry.

A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near-infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially absorbed by oxygenated vs. deoxygenated forms of hemoglobin and myoglobin. Illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition.

A vinyl polymer made from ethylene. It can be branched or linear. Branched or low-density polyethylene is tough and pliable but not to the same degree as linear polyethylene. Linear or high-density polyethylene has a greater hardness and tensile strength. Polyethylene is used in a variety of products, including implants and prostheses.

The largest and strongest bone of the FACE constituting the lower jaw. It supports the lower teeth.

Salts of alginic acid that are extracted from marine kelp and used to make dental impressions and as absorbent material for surgical dressings.

The physical phenomena describing the structure and properties of atoms and molecules, and their reaction and interaction processes.

A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.

Used for general articles concerning statistics of births, deaths, marriages, etc.

The consumption of liquids.

The state of the ATMOSPHERE over minutes to months.

The chemical and physical integrity of a pharmaceutical product.

A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.

A competitive team sport played on a rectangular field. This is the American or Canadian version of the game and also includes the form known as rugby. It does not include non-North American football (= SOCCER).

Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.

Colloids with a solid continuous phase and liquid as the dispersed phase; gels may be unstable when, due to temperature or other cause, the solid phase liquefies; the resulting colloid is called a sol.

Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.

Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.

Substances used on inanimate objects that destroy harmful microorganisms or inhibit their activity. Disinfectants are classed as complete, destroying SPORES as well as vegetative forms of microorganisms, or incomplete, destroying only vegetative forms of the organisms. They are distinguished from ANTISEPTICS, which are local anti-infective agents used on humans and other animals. (From Hawley's Condensed Chemical Dictionary, 11th ed)

Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)

Any substances taken in by the body that provide nourishment.

The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.

Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.

A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.

A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.

The mechanical property of material that determines its resistance to force. HARDNESS TESTS measure this property.

A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.

The infusion of leaves of CAMELLIA SINENSIS (formerly Thea sinensis) as a beverage, the familiar Asian tea, which contains CATECHIN (especially epigallocatechin gallate) and CAFFEINE.

Injuries incurred during participation in competitive or non-competitive sports.

Collection, analysis, and interpretation of data about the frequency, distribution, and consequences of disease or health conditions, for use in the planning, implementing, and evaluating public health programs.

A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.

Behavioral responses or sequences associated with eating including modes of feeding, rhythmic patterns of eating, and time intervals.

A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.

Methods of creating machines and devices.

The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.

The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

A chronic multi-system disorder of CONNECTIVE TISSUE. It is characterized by SCLEROSIS in the SKIN, the LUNGS, the HEART, the GASTROINTESTINAL TRACT, the KIDNEYS, and the MUSCULOSKELETAL SYSTEM. Other important features include diseased small BLOOD VESSELS and AUTOANTIBODIES. The disorder is named for its most prominent feature (hard skin), and classified into subsets by the extent of skin thickening: LIMITED SCLERODERMA and DIFFUSE SCLERODERMA.

Amsorb: a new carbon dioxide absorbent for use in anesthetic breathing systems. (1/634)

BACKGROUND: This article describes a carbon dioxide absorbent for use in anesthesia. The absorbent consists of calcium hydroxide with a compatible humectant, namely, calcium chloride. The absorbent mixture does not contain sodium or potassium hydroxide but includes two setting agents (calcium sulphate and polyvinylpyrrolidine) to improve hardness and porosity. METHODS: The resultant mixture was formulated and subjected to standardized tests for hardness, porosity, and carbon dioxide absorption. Additionally, the new absorbent was exposed in vitro to sevoflurane, desflurane, isoflurane, and enflurane to determine whether these anesthetics were degraded to either compound A or carbon monoxide. The performance data and inertness of the absorbent were compared with two currently available brands of soda lime: Intersorb (Intersurgical Ltd., Berkshire, United Kingdom) and Dragersorb (Drager, Lubeck, Germany). RESULTS: The new carbon dioxide absorbent conformed to United States Pharmacopeia specifications in terms of carbon dioxide absorption, granule hardness, and porosity. When the new material was exposed to sevoflurane (2%) in oxygen at a flow rate of 1 l/min, concentrations of compound A did not increase above those found in the parent drug (1.3-3.3 ppm). In the same experiment, mean +/-SD concentrations of compound A (32.5 +/- 4.5 ppm) were observed when both traditional brands of soda lime were used. After dehydration of the traditional soda limes, immediate exposure to desflurane (60%), enflurane (2%), and isoflurane (2%) produced concentrations of carbon monoxide of 600.0 +/- 10.0 ppm, 580.0 +/- 9.8 ppm, and 620.0 +/-10.1 ppm, respectively. In contrast, concentrations of carbon monoxide were negligible (1-3 ppm) when the anhydrous new absorbent was exposed to the same anesthetics. CONCLUSIONS: The new material is an effective carbon dioxide absorbent and is chemically unreactive with sevoflurane, enflurane, isoflurane, and desflurane. (+info)

Phase transformations and age-hardening behaviors related to Au3Cu in Au-Cu-Pd alloys. (2/634)

Phase transformation behaviors in Au-Cu-Pd alloys were investigated by means of electrical resistivity measurements, hardness tests, X-ray diffraction and transmission electron microscopy. Anisothermal and isothermal annealing were performed. Two types of phase transformations were found, namely related to the single phase of Au3Cu and the coexistent phase of Au3Cu and AuCu I. The latter produced more remarkable hardening than the former. Hardening was brought about by the antiphase domain size effect of Au3Cu ordered phase in the single phase and by the formation of AuCu I ordered phase in the Au3Cu ordered matrix. There are three modes of phase transformation in the coexistent region depending on the composition. Each sequence is discussed. (+info)

Phase transformation mechanisms in (AuCu)1-xPdx pseudobinary alloys by direct aging method. (3/634)

Phase transformation mechanisms in the AuCu-Pd pseudobinary system were studied by means of electrical resistivity measurements, hardness tests, X-ray diffraction and transmission electron microscopy. A direct aging method was employed to eliminate the otherwise unavoidable ordering that takes place rapidly during quenching into ice brine, hence it is important to distinguish the ordering processes with and without an incubation period. Three phase transformation modes occurred, namely; ordering at grain boundaries and in the grain interior with nucleation and growth mechanism after incubation, and spinodal ordering without any incubation period. The age-hardening of the alloys examined was attributed to AuCu I ordering. Nucleation and growth mechanism followed by twinning occurred in the specimens aged at higher temperatures, while spinodal ordering was seen in specimens aged in lower temperature. The spinodal ordering temperature of AuCu-Pd alloys increased according to Pd content. (+info)

Reinforcement mechanism of dentin mechanical properties by intracanal medicaments. (4/634)

The reinforcement mechanism of dentin mechanical properties by intracanal medicaments was investigated. The dumbbell-shaped specimens were prepared from a collagen sheet, demineralized dentin and organic dissolved dentin. After immersing the specimens in intracanal medicaments (eugenol and formocresol), the tensile test was carried out in 37 degrees C water and the Vickers hardness test was performed. The tensile strengths increased after eugenol and formocresol immersion, especially collagen and organic dissolved dentin after formocresol immersion and demineralized dentin after eugenol immersion. Thus, formocresol immersion might have reinforced the dentin tensile strength by protein coagulation, while eugenol immersion might have reinforced the dentin tensile strength by not only protein coagulation but also chelation with hydroxyapatite. However, the hardness values did not significantly change after intracanal medicament immersion. (+info)

Isothermal age-hardening behaviour in a multi-purpose dental casting gold alloy. (5/634)

The isothermal age-hardening behaviour of a multi-purpose dental casting gold alloy was investigated by means of hardness testing, X-ray diffraction study, scanning electron microscopic observations and energy dispersive spectroscopy. By ageing of the solution-treated specimen at 400-500 degrees C, two phases of the Au-rich alpha 1 phase with an f.c.c. structure and the alpha 2 phase with an ordered f.c.c. structure based on Pt3In were transformed into three phases of the alpha 1 phase, the alpha 2 phase and the beta phase with an ordered f.c.t. structure based on PtZn. Hardening was attributed to the fine nodular precipitation resulting from the formation of the beta phase in the alpha 1 matrix. Softening was due to the coarsening of the fine nodular precipitates as the result of consumption of the alpha 2 phase. (+info)

Isothermal age-hardening behaviour in a Au-1.6 wt% Ti alloy. (6/634)

This study describes research with a view to developing a new age-hardenable, high-carat dental gold alloy with better biocompatibility by addition of a small quantity of titanium to gold. The relationship between isothermal age-hardening and phase transformation of the Au-1.6 wt% Ti alloy was investigated by means of hardness testing, X-ray diffraction study, scanning electron microscopic observation and energy dispersive spectroscopy. The hardening in the initial stage of ageing seemed to be attributable to the continuous precipitation of the Au4Ti ordered phase in the supersaturated alpha solid solution matrix. The overaging with softening was attributed mainly to the formation of precipitates at the grain boundaries, which grew to bright lamellae and seemed to be composed of the Au4Ti phase. (+info)

Effects of thermal cycling on dynamic viscoelastic properties of four commercial resins for crown and bridge. (7/634)

To elucidate the effects of thermal cycling on the viscoelastic properties of four commercial resins for crown and bridge, dynamic shear modulus (G'), mechanical loss tangent (tan delta), Knoop hardness, water sorption and appearance of specimen surfaces before and after thermal cycling test were determined. The changes of G' and tan delta for two materials were insignificant with increased repetitions of thermal cycling. Those of the other two materials were statistically significant: in particular, G' at temperatures above 60 degrees C was inclined to increase slightly and tan delta decreased considerably. While the Knoop hardness of the materials was a little decreased over a number of 75,000 thermal cycles, the water sorption almost attained an equilibrium in uptake after 14,000 thermal cycles. Furthermore, cracks on the specimen surface were observed after 37,500 to 75,000 thermal cycles. From these results, the deterioration of materials was observed as damage to the specimen surface. Moreover, it could be presumed that the materials would be further polymerized during the period of thermal cycling. (+info)

Influence of composite inlay/onlay thickness on hardening of dual-cured resin cements. (8/634)

This investigation evaluated the effect of resin composite inlay/onlay thickness on the hardness of a group of eight dual-cure resin-based cements. Fourteen disc specimens measuring 6 mm in diameter and 2.5 mm thick were prepared from each of eight dual-cure cements: Adherence, Choice, Duolink, Enforce, Lute-It, Nexus, Resinomer and Variolink. Two specimens from each material were directly light-cured while the remainder of the specimens were light-cured through resin composite spacers varying in thickness from 1 mm to 6 mm. Curing through the spacers always resulted in a decrease in the Knoop hardness number. For some cements, hardness values were reduced by 50% or more when the resin composite spacer thickness was 4 mm or greater even when measurements were made one week after dual-curing. Low hardness values indicate the presence of a weak chemical-curing mechanism that may compromise cement quality in areas of the cavity not readily accessible to the curing light. (+info)

... hardness can be measured in different ways, such as scratch hardness, indentation hardness, and rebound hardness. Hardness is ... 8. Look up hardness in Wiktionary, the free dictionary. An introduction to materials hardness Guidelines to hardness testing ... Two scales that measures rebound hardness are the Leeb rebound hardness test and Bennett hardness scale. Ultrasonic Contact ... Rebound hardness, also known as dynamic hardness, measures the height of the "bounce" of a diamond-tipped hammer dropped from a ...

https://en.wikipedia.org/wiki/Hardness

... , is a measure of the water hardness caused by the presence of carbonate (CO2− 3) and bicarbonate (HCO− 3) ... Water portal dGH or DGH or Degree of General Hardness, a measure of the hardness of water Hard water "Lime Softening". ... The term carbonate hardness is also sometimes used as a synonym for temporary hardness, in which case it refers to that portion ... whereas Carbonate Hardness CH (mg/L) = [ HCO 3 − ] + [ CO 3 2 − ] {\displaystyle {\text{Carbonate Hardness CH (mg/L)}}=[{\text{ ...

https://en.wikipedia.org/wiki/Carbonate_hardness

Vickers Hardness, Rockwell Hardness, Superficial Hardness, Knoop Hardness, Scleroscope Hardness, and Leeb Hardness" (2019) ... ISO 18265: "Metallic materials - Conversion of hardness values" (2013) ASTM E140-12B(2019)e1: "Standard Hardness Conversion ... A variety of hardness-testing methods are available, including the Vickers, Brinell, Rockwell, Meyer and Leeb tests. Although ... Struers hardness conversion table (Vickers, Brinell, Rockwell B,C,D) (Articles with short description, Short description is ...

https://en.wikipedia.org/wiki/Hardness_comparison

... hot hardness or red hardness (when a metal glows a dull red from the heat) corresponds to hardness of a material at high ... hardness decreases and at some point a drastic change in hardness occurs. The hardness at this point is termed the hot or red ... "Red-Hardness". TheFreeDictionary.com. Retrieved 2016-07-18. Shaffer, S. J. (3 March 2014). "Hardness Testing at Elevated ... v t e (Hardness tests, Solid mechanics, All stub articles, Classical mechanics stubs). ...

https://en.wikipedia.org/wiki/Hot_hardness

... refers to the hardness of a material in terms of resistance to scratches and abrasion by a harder material ... Scratch hardness test or scratch test refers to any of a number of methods of measuring scratch hardness. Resistance to ... modified the Mohs scale by giving garnet a hardness of 10 and diamond a hardness of 15. Charles E. Wooddell, working at the ... Scratch hardness is measured with a sclerometer. Attempting to scratch a surface to test a material is a very old technique. ...

https://en.wikipedia.org/wiki/Scratch_hardness

In computational complexity theory, NP-hardness (non-deterministic polynomial-time hardness) is the defining property of a ...

https://en.wikipedia.org/wiki/NP-hardness

... may refer to: Scratch hardness The Mohs scale of mineral hardness The Vickers hardness test The Brinell scale ... The Barcol scale The Leeb rebound hardness scale The Rosiwal scale The Meyer hardness test The Knoop hardness test Hardness ... The scale of Pencil hardness This disambiguation page lists articles associated with the title Hardness scales. If an internal ... The Janka hardness test The Rockwell scale The Durometer scale ...

https://en.wikipedia.org/wiki/Hardness_scales

Janka hardness test, for wood Meyer hardness test Rockwell hardness test (HR), principally used in the USA. HRA, HRB and HRC ... Vickers hardness test (HV) Knoop hardness test (HK) In microindentation testing, the hardness number is based on measurements ... The hardness number is based on the applied force divided by the surface area of the indent itself, giving hardness units in ... Leeb rebound hardness test Meyer's law Correlation of Yield Strength and Tensile Strength with Hardness for Steels , E.J. ...

https://en.wikipedia.org/wiki/Indentation_hardness

Brinelling Hardness comparison Knoop hardness test Leeb rebound hardness test Rockwell scale Vickers hardness test Fischer- ... The Meyer hardness test is a hardness test based upon projected area of an impression. The hardness, H {\displaystyle H} , is ... Based on Meyer's law hardness values from this test can be converted into Brinell hardness values, and vice versa. The Meyer ... Tabor, David (2000). The Hardness of Metals. Oxford University Press. ISBN 0-19-850776-3.. v t e (Hardness tests, All stub ...

https://en.wikipedia.org/wiki/Meyer_hardness_test

Tablet hardness testers first appeared in the 1930s. In the 1950s, the Strong-Cobb tester was introduced. It was patented by ... Strong-Cobb (SC) - An ad hoc unit of force which is a legacy of one of the first tablet hardness testing machines. Although the ... Tablet hardness testing is a laboratory technique used by the pharmaceutical industry to determine the breaking point and ... Newton (N) - The Newton is the SI unit of force; the standard for tablet hardness testing. 9.807 Newtons = 1 kilogram (at one G ...

https://en.wikipedia.org/wiki/Tablet_hardness_testing

Brinell hardness test Knoop hardness test Rockwell scale Shore durometer Vickers hardness test Hardness comparison "A model ... Barcol hardness is not a valid hardness measure for curved surfaces. The governing standard for the Barcol hardness test is ... The Barcol hardness test is generally used on soft materials such as rigid plastics. It measures hardness based on indentation ... A measurement of 60B is roughly equivalent to a Shore hardness of 80D or a Rockwell hardness M100. As defined in ASTM D 2583 ...

https://en.wikipedia.org/wiki/Barcol_hardness_test

... "end hardness".[citation needed] Side hardness may be further divided into "radial hardness" and "tangential hardness", although ... Janka Hardness Scale For Wood - Side Hardness Chart of Some Woods USDA - Wood Handbook - Wood as an Engineering Material USDA ... "Janka hardness". Sizes.com. Retrieved 4 May 2021. "What is the Janka Hardness Scale". Avant Garde Flooring. 10 March 2019. ... The hardness of wood varies with the direction of the wood grain. Testing on the surface of a plank, perpendicular to the grain ...

https://en.wikipedia.org/wiki/Janka_hardness_test

A roll hardness tester is a device to measure the roll hardness, hardness profile and hardness variation of paper rolls. In the ... The rebound distance depends directly on the hardness of the roll under test: A softer roll will absorb more of the impact ... Above all, it is typically the variation in hardness across a given roll that relates most directly to such converting issues ... TAPPI T 834 om-07: Determination of containerboard roll hardness TAPPI TIP 1004-01: TAPPI Roll Number for inventory/tracking ...

https://en.wikipedia.org/wiki/Roll_hardness_tester

For a given problem, average-case hardness implies worst-case hardness, so an average-case hardness assumption is stronger than ... hardness for essentially any useful problem. Instead, computer scientists rely on reductions to formally relate the hardness of ... Average-case computational hardness assumptions are useful for proving average-case hardness in applications like statistics, ... Roughly, a computational hardness assumption is said to be falsifiable if it can be formulated in terms of a challenge: an ...

https://en.wikipedia.org/wiki/Computational_hardness_assumption

... theory deals with studying the approximation threshold of such problems. For an example of an NP-hard ... In computer science, hardness of approximation is a field that studies the algorithmic complexity of finding near-optimal ... Hardness of approximation complements the study of approximation algorithms by proving, for certain problems, a limit on the ... In the 1970s, Teofilo F. Gonzalez and Sartaj Sahni began the study of hardness of approximation, by showing that certain ...

https://en.wikipedia.org/wiki/Hardness_of_approximation

Vickers hardness test Knoop hardness of ceramics Leeb Rebound Hardness Test Meyer hardness test "Microhardness Test", Surface ... The Knoop hardness test /kəˈnuːp/ is a microhardness test - a test for mechanical hardness used particularly for very brittle ... cite journal}}: Missing or empty ,title= (help) efunda Dental hardness tables (CS1 errors: missing title, Hardness tests). ... The Knoop hardness HK or KHN is then given by the formula: H K = load ( kgf ) impression\ area ( mm 2 ) = P C p L 2 {\ ...

https://en.wikipedia.org/wiki/Knoop_hardness_test

Indentation hardness Leeb Rebound Hardness Test Hardness comparison Knoop hardness test Meyer hardness test Rockwell scale ... to get the hardness in MPa (N/mm²) and furthermore divided by 1000 to get the hardness in GPa. surface area hardness (GPa) = g ... Tables of hardness values ISO 18265: Metallic materials - Conversion of Hardness Values Video on the Vickers hardness test ... The unit of hardness given by the test is known as the Vickers Pyramid Number (HV) or Diamond Pyramid Hardness (DPH). The ...

https://en.wikipedia.org/wiki/Vickers_hardness_test

Vickers Hardness, Rockwell Hardness, Superficial Hardness, Knoop Hardness, Scleroscope Hardness, and Leeb Hardness" Official ... Leeb hardness test - Part 3: Calibration of reference test blocks" Meyer hardness test R. T. Mennicke, "Equotip Metal Hardness ... Equotip hardness results in HLx are often converted to the traditional hardness scales HRC, HB and HV mainly for convention ... impact device D with hardness unit HLD Equotip impact device G with hardness unit HLG Equotip impact device C with hardness ...

https://en.wikipedia.org/wiki/Leeb_rebound_hardness_test

... hardness 8, quartz - hardness 7, orthoclase feldspar - hardness 6, plagioclase feldspar - hardness 6 to 6.5, mica - hardness 2 ... Knoop hardness test Meyer hardness test Pencil hardness Rockwell scale Rosiwal scale Scratch hardness Superhard material von ... Comparison between Mohs hardness and Vickers hardness: Brinell scale Geological Strength Index Hardnesses of the elements (data ... in which the well-known hardness scale was set up.] "Mohs hardness" in Encyclopædia Britannica Online "Mohs scale of hardness ...

https://en.wikipedia.org/wiki/Mohs_scale_of_mineral_hardness

... is the second album by the American funk band Slave, released in 1977, their second album release ... Slave - The Hardness of the World Album Reviews, Songs & More at AllMusic. Retrieved 1 December 2022. The Rolling Stone Album ... Slave - The Hardness Of The World at Discogs (Articles with short description, Short description is different from Wikidata, ...

https://en.wikipedia.org/wiki/The_Hardness_of_the_World

Mohs scale of mineral hardness Mohs hardness of materials (data page) Vickers hardness test Brinell scale (Articles needing ... Hardness can vary by several hundred percent depending on the pretreatment, see e.g. Iron#Mechanical properties and Angelo ...

https://en.wikipedia.org/wiki/Hardnesses_of_the_elements_(data_page)

"Hardness: Vickers, Rockwell, Brinell, Mohs, Shore and Knoop - Matmatch". matmatch.com. Retrieved 4 October 2021. "Hardness". 7 ... The hardness of a mineral defines how much it can resist scratching. This physical property is controlled by the chemical ... A mineral's hardness is not necessarily constant for all sides, which is a function of its structure; crystallographic weakness ... The 2:1 clay minerals (pyrophyllite-talc) consist of T-O-T stacks, but they are softer (hardness from 1 to 2), as they are ...

https://en.wikipedia.org/wiki/Mineral

"Mohs Hardness Test". www.oakton.edu. Retrieved 2019-12-20. "Hardness". Earth's Minerals. learnbps.bismarckschools.org. ... It has a brassy to golden yellow color and a hardness of 3.5 to 4 on the Mohs scale. Its streak is diagnostic as green-tinged ... Some important mineral characteristics that help distinguish these minerals are hardness and streak. Chalcopyrite is much ...

https://en.wikipedia.org/wiki/Chalcopyrite

The display explains how minerals are different from rocks, and has sections about: mineral colour; streak; hardness; magnetism ...

https://en.wikipedia.org/wiki/Cliffe_Castle_Museum

Indentation hardness; and Rebound, or dynamic, hardness measured with a Shore scleroscope. Of these, indentation hardness ... However, there is not always a simple relationship between the various hardness scales. Vickers and Rockwell hardness numbers ... Vickers hardness test - using a pyramidal diamond indenter; and Rockwell hardness test - using a diamond cone indenter. In all ... Unlike temperature and electric current, there is no abstract physical concept of the hardness of a material. It is a slightly ...

https://en.wikipedia.org/wiki/Operational_definition

The hardness is due to water being obtained from underground chalk sources by the water company Southern Water. In East Kent, ... "Water Hardness". Southern Water. Retrieved 21 June 2007. "Wye 1971-2000 averages". Met Office. Archived from the original on 29 ...

https://en.wikipedia.org/wiki/Birchington-on-Sea

ISBN 978-0-415-14098-0.; "Water Hardness". Waterwise.org.uk. 2006. Archived from the original on 15 March 2017. Retrieved 14 ...

https://en.wikipedia.org/wiki/Northern_England

Hardness = ~2. Radioactive. Contents of Al and U are very stable (1±0.05 and 2±0.07 atoms per As+P+U = 4 apfu respectively). ...

https://en.wikipedia.org/wiki/Arsenuranospathite

North West England is the wettest region in England, and water hardness across the region is soft to very soft. In 1989 the ... "Water hardness". www.unitedutilities.com. Retrieved 14 August 2020. "United Utilities - Share price history". www. ...

https://en.wikipedia.org/wiki/United_Utilities

Pearson, Ralph G. (1997). "The HSAB Principle". Chemical Hardness. Wiley-VCH Verlag GmbH & Co. KGaA. pp. 1-27. doi:10.1002/ ...

https://en.wikipedia.org/wiki/Klopman-Salem_equation

... - From Healing Crystals, a Metaphysical Crystal store selling high quality Crystal Jewelry, ...

https://www.healingcrystals.com/products-by-2.5-hardness-hardness.html?tab=7&shape=Bracelets

Hardness in drinking-water : background document for development of WHO guidelines for drinking-water quality ...

https://apps.who.int/iris/browse?locale-attribute=en&type=mesh&authority=Hardness

Roundness, Hardness. Sharply defined shapes in contrasting colors. Pink, yellow, black. In the prints of Gunnar S. Gundersen ...

https://www.uib.no/en/arts-and-gardens/78061/roundness-hardness

Commercial standardized hardness test blocks were machined to ... Commercial standardized hardness test blocks were machined to " ... A study was performed in an attempt to resolve the conflicting thickness requirements for Rockwell hardness testing specified ... Rockwell hardness tests were performed on the original standardized surface of these "stepped" blocks in an attempt to ... The extremes of test force and hardness were investigated for both the diamond brale and 1/16 in. (1.588 mm) ball indenters. ...

https://www.astm.org/jte12687j.html

Hardness in drinking-water : background document for development of WHO guidelines for drinking-water quality ...

https://extranet.who.int/iris/restricted/browse?authority=Hardness&type=mesh

... There are different Shore Hardness scales for measuring the hardness of different materials. ... The Shore 00 Hardness Scale measures rubbers and gels that are very soft.. The Shore A Hardness Scale measures the hardness of ... What Shore Hardness means to you as a mold maker:. Shore Hardness becomes an important factor when considering which mold ... The different Shore Hardness scales measure the resistance of a material to indentation. A Shore Hardness gauge (looks like a ...

https://www.smooth-on.com/page/durometer-shore-hardness-scale/

Article A Multipurpose Hardness Test/ Eine vielseitige Härteprüfung was published on May 1, 1991 in the journal International ... A Multipurpose Hardness Test/ Eine vielseitige Härteprüfung. Primo Gondi and Andrea Sili ... "A Multipurpose Hardness Test/ Eine vielseitige Härteprüfung" International Journal of Materials Research, vol. 82, no. 5, 1991 ... "A Multipurpose Hardness Test/ Eine vielseitige Härteprüfung" International Journal of Materials Research 82, no. 5 (1991): 377- ...

https://www.degruyter.com/document/doi/10.1515/ijmr-1991-820507/html

... hardness scale section of WPClipart, quality Public Domain pictures and artwork. ...

https://wpclipart.com/rocks_minerals/hardness_scale/

colorimetric, water hardness 5-25 °d, for use with MQuant® StripScan App, water hardness 6-31 °e, water hardness 9-45 °f, ... colorimetric, water hardness 3-21 °d, water hardness 4-26 °e, water hardness 5-37 °f, MQuant® ... This MQuant® Total Hardness test (formally MColortest®) is suitable for the titrimetric determination using a convenient ...

https://www.sigmaaldrich.com/CH/de/product/mm/111104

Thou therefore endure hardness, as a good soldier of Jesus Christ. ... 3 Thou therefore endure hardness, as a good soldier of Jesus Christ. ...

https://www.biblegateway.com/passage/?version=KJV&search=%20%202%20Timothy%20+%202:3

... or do you know of anyone using this type of portable hardness tester? - see link below - model Qualimag DR... ... What kind of hardness tester you are using right now. I am looking for a hardness tester and our products are also small , ... At the time, I did not know hardness testing required that massive of parts. Our parts are too small for portable hardness ... phoenix, if your parts are too small for Rockwell hardness, the only reliable way to get a hardness reading will be by ...

https://elsmar.com/elsmarqualityforum/threads/portable-magnetic-hardness-testers-aerospace.68912/

... - From Healing Crystals, a Metaphysical Crystal store selling high quality Crystal Jewelry, ...

https://www.healingcrystals.com/products-by-2.5-hardness-hardness.html?tab=7

Jesus said that it was the hardness of heart of the people that caused Moses to allow divorce, while critics say it is hardness ... So while I doubt that society will anytime soon learn that it is their hardness of heart and not the Churchs in regard to ...

https://www.splendoroftruth.com/curtjester/2007/08/hardness-of-heart/?replytocom=29606

This is hot-swappable with access at the front of Dells servers. That means failed units can readily be replaced and ones with more capacity could replace existing ones or be added to empty slots alongside them.. Micron has developed its own hardware controller for this SSD, with firmware and software. It has a combo connector that allows the device to be plugged into backplanes where there are also SAS and SATA devices.. The P320h is a half-height, half-length (HHHL) PCIe gen 2 x8 interface card with 350GB or 750GB capacity using 34nm SLC flash chips. Putting it into a SSD form factor means less physical space, and capacity drops to 150GB or 300GB and there us an x4 PCIe 2 interface. Micron isnt giving away any details; more will be provided at a launch later this year. But the 350GB P320h does 715,000 random read IOPS, 298,000 random writes, has a 3.3GB/sec sequential read bandwidth and a 2GB/sec sequential write bandwidth. We might expect the SSD-packaged version to be in the same ...

https://www.theregister.com/2012/03/07/micron_pcie_ssd/

Products » Testing Accessories » Application Specific Fixtures » Wood » Compression » Hardness Fixture Hardness Fixture for ... S1-11892-2 , Wood Hardness Test Fixture. Per ASTM D143/D1037. Upper connection: Type Dm (1.25 in connection with 1/2 in clevis ...

https://www.instron.com/en-gb/products/testing-accessories/application-specific-accessories/wood/compression/s1-11892-2

Bel-India.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.in. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.in, Inc. or its affiliates.. ...

https://www.bel-india.com/tag/hardness/

... 04/11/2015 ... Groundwater hardness arises mainly from the solution of limestone into groundwater. Many Irish industrial and domestic water ... Geological Survey Ireland has created a preliminary Total Hardness map for Irish groundwaters. It is based on groundwater ... users are concerned about the hardness of their water and invest in water softeners to counteract the impacts of hard water. ...

https://www.gsi.ie/ga-ie/publications/pages/preliminary-groundwater-total-hardness-map.aspx

Professional tablet hardness tester to measure weight, thickness, width, diameter/length and hardness of virtually all tablet ... diameter/length and tablet hardness measurements in a single report. Samples are placed inside the MultiTest 50 test area ...

https://pharmaceutical-business-review.com/products/multitest-50-tablet-hardness-tester/

To prove the Positivity- and hence Skolem-hardness for the latter two problems, a new auxiliary path measure, called weighted ... long-run frequency, is introduced and the Positivity-hardness of the corresponding decision problem is shown as an intermediate ... On Skolem-hardness and saturation points in Markov decision processes. @article{Piribauer2020OnSA, title={On Skolem-hardness ... showing decidability in the case of one parameter and Skolem-hardness with two or more parameters, and a reduction from the ...

https://www.semanticscholar.org/paper/On-Skolem-hardness-and-saturation-points-in-Markov-Piribauer-Baier/1657b62b3f46385b43bc2e5ca3429f284e612612

The Janka Scale is a comprehensive chart of hardness ratings for a huge variety of wood species used for hardwood floors. Learn ... What The Wood Hardness Scale Looks Like. Janka Hardness Scale. The Janka Hardness Scale starts at zero, with this option being ... Where The Wood Hardness Scale Comes From. The scale was developed as a means for displaying the results of the Janka hardness ... Dont confuse the hardness of the flooring with its strength. The hardness serves only as an indicator of how well the floor ...

https://www.builddirect.com/learning-center/flooring/bamboo-flooring/janka-hardness-rating-scale/

https://builddirect.com/learning-center/flooring/bamboo-flooring/janka-hardness-rating-scale/

The hardness value is near the limit (within 15%) of the acceptable range of the particular hardness scale. ... The many hardness tests listed here measure hardness under different experimental conditions (e.g. indenters made in different ... The hardness value is below the acceptable range of the particular hardness scale. ... The hardness value is above the acceptable range of the particular hardness scale. ...

https://www.efunda.com/units/hardness/convert_hardness.cfm?cat=Steel&HD=HR-15N

Water Hardness Tester, Corrosion Control Test Kit, …of 5 grains per gallon indicates moderately hard water. The.. ... Related Categories: Water Hardness Test Kit , Water Hardness Test , Portable Water Quality Testing Kit , Chlorine Meter , ... Related Categories: Water Hardness Test Kit , Water Hardness Test , Portable Water Quality Testing Kit , Chlorine Meter , ... Product Directions The Hydrion Water Hardness Test Kit eliminates the need for expensive… ...

https://www.thomassci.com/scientific-supplies/Water-Hardness-Tester

Applied Technical Services has the capability to offer on-site Hardness Tester Calibrations at your facility per ATSM standards ... Standard Rockwell Hardness Testers which include C, B, and A Scales. To certify your Standard Rockwell Hardness tester to the ... Superficial Rockwell Hardness Testers which include 15, 30, 45 N and T Scales. To certify your Superficial Rockwell Hardness ... Twin Scale Hardness Testers which include C, B, and A Scales plus 15, 30, 45 N and T Scales. To certify your Superficial ...

https://atslab.com/calibrations/hardness-tester-calibrations/

Determination of surface scratch hardness according to the Mohs scale ... This document specifies a method of test for determining the scratch hardness of the surface of vitreous and porcelain enamels. ... Vitreous and porcelain enamels - Determination of surface scratch hardness according to the Mohs scale. ...

https://www.iso.org/standard/82365.html

City AVG Hardness PPM / mg/L AVG Hardness Grains per Gallon Blue Springs 114 6.7 Columbia 170 10 Independence 120 7.1 Kansas ... Here are the water hardness values for the cities in Missouri. ... AVG Hardness PPM / mg/L. AVG Hardness Grains per Gallon. Blue ... Here are the water hardness values for the cities in Missouri.. City. ...

https://www.aquatell.com/pages/water-hardness-missouri

The relative hardness of a wood refers to the force required to insert a .444 inch steel ball to half of its diameter into ... Wood Hardness. Relative Hardness (Janka Scale). The relative hardness of a wood refers to the force required to insert a .444 ...

https://www.stairsupplies.com/resources/wood-stair-advice/wood-hardness/

... Authors:. Yvo Desmedt Yongge Wang ... inproceedings{asiacrypt-1999-172, title={Approximation Hardness and Secure Communication in Broadcast Channels}, booktitle={ ...

https://www.iacr.org/cryptodb/data/paper.php?pubkey=172

We provide results showing that our hardness and transferability estimates are strongly correlated with empirical hardness and ... We further show how to use this value to estimate task hardness. We test our claims extensively on three large scale data sets ... We provide results showing that our hardness and transferability estimates are strongly correlated with empirical hardness and ... We further show how to use this value to estimate task hardness. We test our claims extensively on three large scale data sets ...

https://ui.adsabs.harvard.edu/abs/2019arXiv190808142T/abstract

Here are the water hardness values for the cities in Missouri. (aquatell.com)
Water Hardness - The systems are interconnected in some areas so water is blended and concentrations may vary. (metrowater.com)

Brinell Hardness Testers (500, 1500, and 3,000 kg loads) are calibrated with NVLAP certified blocks and are calibrated in accordance with the latest revision of ASTM E10. (atslab.com)
Like the Rockwell scale, Brinell hardness testing typically concerns larger loads approaching a nominal maximum force of 3,000kgf which requires a larger, harder indenter tip. (clemex.com)
As a result, Brinell hardness testing is typically used for larger samples. (clemex.com)
Universal hardness tester with load cell technology for the automatic hardness testing of Brinell, Vickers, Rockwell, and Knoop With an extended load range of 9.8 N to 2450 N (1-250 kgf). (struers.com)

phoenix, if your parts are too small for Rockwell hardness, the only reliable way to get a hardness reading will be by sectioning, mounting and polishing and measuring using Vickers microhardness. (elsmar.com)
Finally, Vickers hardness testing is most like Knoop microhardness in that it involves loads of no greater than 1kgf and eschews the ball-shaped indenters of production-scale hardness testers. (clemex.com)
Aim: To evaluate the hardness (Vickers hardness) and chemical composition of miniimplant titanium alloys from five commercial brands. (bvsalud.org)
The hardness and chemical composition of the titanium alloys were performed by the Vickers hardness test and energy dispersive X-ray spectroscopy, respectively. (bvsalud.org)
Results: Vickers hardness was significantly higher in SIN implants than in NEO, MOR, and CON implants. (bvsalud.org)

This MQuant ® Total Hardness test (formally MColortest ® ) is suitable for the titrimetric determination using a convenient dropping bottle. (sigmaaldrich.com)
The total hardness is determined from the consumption of titration solution. (sigmaaldrich.com)
Geological Survey Ireland has created a preliminary Total Hardness map for Irish groundwaters. (gsi.ie)
There are two sub-divisions of general or total hardness, often abbreviated to GH. (megahowto.com)
Determination of Total Hardness. (vecom-marine.com)
TEST KIT TOTAL HARDNESS is suitable for measuring total hardness in any water system. (vecom-marine.com)

The relative hardness of a wood refers to the force required to insert a .444 inch steel ball to half of its diameter into a piece of wood. (stairsupplies.com)
In the early 19th century, Friedrich Mohs developed a scale of relative hardness for minerals. (gemologyproject.com)
Obviously, you will not be able to alter the relative hardness of your water supply at source, but you may need to adjust it to meet the requirements of your fish. (megahowto.com)
The relative hardness of water reflects the amount of dissolved salts present in it. (megahowto.com)
There are test kits available so you can check your tap water quite easily, to gain an accurate indication of its relative hardness, and you can measure both temporary and permanent hardness separately. (megahowto.com)
Relative hardness (mg/litre of calcium carbonate) = (volume in litres x hardness of hard water) + (volume in litres x hardness of soft water), divided by the total volume of water. (megahowto.com)
That's one way of determining relative "hardness", apart from the starting point of a given speaker's native language. (economist.com)

Is anyone using - or do you know of anyone using this type of portable hardness tester? (elsmar.com)
What kind of hardness tester you are using right now. (elsmar.com)
I am looking for a hardness tester and our products are also small , general surgical instruments like forceps and scissors , clamps, rongeurs etc. (elsmar.com)
Professional tablet hardness tester to measure weight, thickness, width, diameter/length and hardness of virtually all tablet shapes. (pharmaceutical-business-review.com)
Applied Technical Services offers on-site hardness tester calibrations. (atslab.com)
To certify your Standard Rockwell Hardness tester to the current revision of ASTM E18, you are required to have certified penetrators. (atslab.com)
Our top quality Pusey & Jones (P&J) hardness tester (Plastometer) is the most popular model in the market for determination of the penetration depth on rubber and elastomer materials e.g. rubber rollers and standard blocks made of rubber with a minimum thickness of 13 mm as well as paper rollers. (worldoftest.com)
The big advantage of this is that the display of the dial gauge can be set for zero by pressing a key, as soon as the indenter with measuring rod is raised approximately for about 3 mm after lowering the body of the hardness tester. (worldoftest.com)
By an integrated vertical spindle, which is at the back of the hardness tester, the dial gauge can be lifted or lowered sensitively. (worldoftest.com)
With the help of precise and user-friendly design of our P&J hardness tester, you can perform easy, quick and repeatable measurements under load. (worldoftest.com)
Our customer who produces rubber rolls will be able to determine the hardness of the rubber efficiently every day now with the purchase of the P&J tester. (worldoftest.com)
It is a universal hardness tester, operated by a robust touchscreen, and comes available in three load ranges and with an optional motorized Z-table for larger samples. (struers.com)

The Shore 00 Hardness Scale measures rubbers and gels that are very soft. (smooth-on.com)
The Shore A Hardness Scale measures the hardness of flexible mold rubbers that range in hardness from very soft and flexible, to medium and somewhat flexible, to hard with almost no flexibility at all. (smooth-on.com)
The Shore D Hardness Scale measures the hardness of hard rubbers, semi-rigid plastics and hard plastics. (smooth-on.com)
The hardness scale is not like stairs, with one being incrementally stronger than the previous one, but more like stepping stones that are sometimes closer or further apart than others. (americangemsociety.org)
What is the Janka Hardness Scale? (builddirect.com)
The Janka Hardness Scale determines the hardness of a particular type of wood over another. (builddirect.com)
The scale was developed as a means for displaying the results of the Janka hardness test. (builddirect.com)
Wood is also tested on the sides or ends because that provides a different hardness rating, but these ratings are not displayed on the typical hardness scale. (builddirect.com)
The Janka Hardness Scale starts at zero, with this option being the softest wood choice, making it easy to dent and scratch. (builddirect.com)
Where do engineered hardwoods stand on the Janka Hardness Scale? (builddirect.com)
Since these hardwoods are made with a layer of softer wood beneath them, their hardness cannot really be gauged correctly with the scale. (builddirect.com)
The hardness value is below the acceptable range of the particular hardness scale. (efunda.com)
Twin Scale Hardness Testers which include C, B, and A Scales plus 15, 30, 45 N and T Scales. (atslab.com)
The Mohs Hardness Scale 9 Corundum 8 Topaz 7 Quartz 6 Feldspar 5 Apatite. (pixaria.com)
MOHS' SCALE OF HARDNESS Mineral Hardness Diamond 10 Zaire 1 cm. 14 carats Corundum 9 variety ruby, India 6 cm. (pixaria.com)
What is a 9 on the hardness scale? (pixaria.com)
Corundum (9) is twice as hard as topaz (8), and diamond (10) is four times as hard as corundum.The Mohs Scale of Hardness. (pixaria.com)
Friedrich Mohs, a German mineralogist, developed the scale in 1812.What is Mohs Hardness Scale? (pixaria.com)
Mohs Hardness Scale Mineral Hardness Topaz 8 Corundum 9 Diamond 10. (pixaria.com)
The Mohs scale of hardness uses talc as its starting-point, with a value of 1. (pixaria.com)
Mohs Hardness Scale Hardness Index Minerals Common Objects 6 apatite 6 to 6.5-hard steel file 7 quartz 8 topaz. (pixaria.com)
Talc is the softest mineral on the Mohs hardness scale at 1 and can be easily cut and crushed. (pixaria.com)
He composed a list of 10 minerals with known hardness and organized them on an ascending scale, with talc at the lower end and [[diamond]] at the highest end. (gemologyproject.com)
Thus it is a comparative hardness scale, with the hardness of one mineral relative to another mineral on the list. (gemologyproject.com)
As can be seen in the list, quartz has a hardness of 7 on Mohs scale. (gemologyproject.com)
Hardness pencils=== Hardness pencils are pencils with a tip made of one of the 10 minerals on Mohs scale. (gemologyproject.com)
For instance, if one could not scratch the mineral with pencil no.7 but it would leave a scratch with pencil no.8, the hardness of the mineral must be between 7 and 8 on Mohs scale. (gemologyproject.com)
Unfortunately, there is no single universal scale used to measure hardness, and this can give rise to confusion. (megahowto.com)
What Is Mohs Hardness Scale? (expii.com)
Indepth studies were carried out at University B.D.T College of Engineering, Davangere, Karnataka, to assess the performance of bench scale softeners of D to H ratio 1:2, 1:3, 1:4 in removing hardness of varied concentrations from both synthetic and natural water samples. (who.int)

A study was performed in an attempt to resolve the conflicting thickness requirements for Rockwell hardness testing specified in ASTM Standard Test Methods E 18-93 and in ISO Standard 6508. (astm.org)
Rockwell hardness tests were performed on the original standardized surface of these "stepped" blocks in an attempt to determine the minimum thicknesses required for reliable Rockwell hardness testing. (astm.org)
Hardness and impact test were carried out using charpy impact test machine for impact test and Rockwell hardness testing machine (ASTM E18-11) used to measure the hardness test. (eajournals.org)

Knoop hardness testing was developed specifically to enable characterizations of brittle, or thin samples like ceramics or surface coatings. (clemex.com)

Even still, a "good" Janka rating serves only as an indication, because it is not just the hardness that plays a role in the appearance and durability of a floor over time. (builddirect.com)
What Is A "Bad" Janka Hardness Rating? (builddirect.com)
The Janka (or side) hardness test measures the force required to embed a .444 - inch steel wall to half its diameter in wood. (mesquitefloors.com)
Northern Red Oak, for example, has a Janka hardness rating of 1290. (mesquitefloors.com)

Standard Rockwell Hardness Testers which include C, B, and A Scales. (atslab.com)
Superficial Rockwell Hardness Testers which include 15, 30, 45 N and T Scales. (atslab.com)

Indentation hardness test was applied for this research. (eajournals.org)
In this article, we want to look into the four different methods of indentation hardness testing methods. (clemex.com)

Depending on the room where the flooring will be installed, a certain level of hardness may make it a more desirable choice. (builddirect.com)

Carbonate hardness (temporary hardness) is from carbonates/bicarbonates where most of us just use baking soda (sodium bicarbonate) to raise it's level to 5 dKH. (barrreport.com)
One part is temporary hardness, which can be removed by simply boiling the water. (megahowto.com)

Although I can't answer your question with any authority I'll be lurking on this thread as I need to understand the importance of the chemicals that constitute permanent hardness and their effect on plant growth. (barrreport.com)

The method of testing the hardness of gemstones is by the use of hardness pencils. (gemologyproject.com)
The wood used to make these pencils is of a hardness that allows for crisp sharpening for superb pointing and less waste. (jerrysartarama.com)

There is a need to address the problems of hardness and fluoride in subsurface water on priority basis. (who.int)

Improvement in erection hardness and intercourse success with first dose of sildenafil citrate 100 mg. (bvsalud.org)
To determine, in men with erectile dysfunction (ED), the extent of improvement in erection hardness and in the rate of successful sexual intercourse (SSI) during the final intercourse attempt using sildenafil 50 mg compared with the subsequent initial attempt after a dose increase to 100 mg. (bvsalud.org)
The main outcome measures were event log data, including an Erection Hardness Score (EHS) and a question on SSI ("Did your erection last long enough for you to have successful sexual intercourse ? (bvsalud.org)

Commercial standardized hardness test blocks were machined to "steps" of various thicknesses using a wire EDM (electrical discharge machining) process. (astm.org)
The extremes of test force and hardness were investigated for both the diamond brale and 1/16 in. (astm.org)
A Multipurpose Hardness Test/ Eine vielseitige Härteprüfung" International Journal of Materials Research , vol. 82, no. 5, 1991, pp. 377-382. (degruyter.com)
Gondi, P. and Sili, A. (1991) A Multipurpose Hardness Test/ Eine vielseitige Härteprüfung. (degruyter.com)
The Rockwell Hardness Test presses a steel or diamond hemisphere-conical penetrator against a test specimen and measures the resulting indentation depth as a gage of the specimen hardness. (efunda.com)
Instead, one must correlate test results across the multiple hardness tests. (efunda.com)
This document specifies a method of test for determining the scratch hardness of the surface of vitreous and porcelain enamels. (iso.org)
Other water balance levels are slower to change, but be sure to test and adjust alkalinity, hardness and stabilizer levels every spring, and each month during the season. (intheswim.com)
Essentially, hardness is only a measure of how well a material performs in a given hardness test. (clemex.com)
First developed over one hundred years ago, the Rockwell hardness test is a rapid hardness testing method primarily used for quality assurance and production control. (clemex.com)
Our systems cover test loads of 0.3 kgf up to 30kgf, with high flexibility for distinct hardness testing methods. (clemex.com)

The difference in actual hardness between diamond and corundum is 10 times higher than the difference between talc and corundum [Read, 2005]. (gemologyproject.com)

The MultiTest 50 is a manual multi-purpose instrument that accumulates weight, thickness, width, diameter/length and tablet hardness measurements in a single report. (pharmaceutical-business-review.com)

Hardness is largely made up by calcium and magnesium carbonates. (vecom-marine.com)

Once the gauge is pressed firmly against the material and the needle has penetrated as far as it can go, the measurement needle will indicate the corresponding hardness measurement. (smooth-on.com)

This paper studies the effect of strontium on the hardness and impact strength of aluminium-1.0%manganese-12%Si alloy. (eajournals.org)
If mineral hardness is the determining factor of strength then diamond is technically the strongest rock in the world. (pixaria.com)
Then, the waste plastic crushing …Hammer crusher is especially suitable for crushing limestone and medium hardness stone with compressive strength below 200Mpa. (danslacreuse.fr)
Type 17-7PH® provides high strength and hardness, excellent fatigue properties, good corrosion resistance and minimum distortion upon heat treatment. (ulbrich.com)

The accurate and repeatable loading system based on load cell technology, combined with advanced software algorithms, ensures specific and repeatable image and hardness evaluation. (struers.com)

This makes hardness a reliable diagnostic property for most minerals. (pixaria.com)
This is why minerals with a hardness less than 7 will abrade relatively rapidly with normal wear. (gemologyproject.com)
Directional hardness=== Due to various causes, some minerals are harder in one direction than in another direction. (gemologyproject.com)

High chromium alloy crusher hammer is particularly suitable for crushing high hardness materials, such as quartz stone and basalt. (danslacreuse.fr)

Chemical parameters (hardness, free chlorine, associated with other bacteria and protozoa (10,11). (cdc.gov)

Diamond is a high-symmetry allotrope of carbon (C). It has a Mohs "scratch" hardness of 10, which makes it the hardest mineral known to date. (pixaria.com)
The gemstone is tested with a pencil of low hardness (starting at 4 or lower) to try to put a tiny scratch on the stone without applying pressure. (gemologyproject.com)
If no scratch is observed, one repeats this process with a pencil of higher hardness (in this case 5) and so on until one arrives at the pencil that is able to put a tiny scratch on the stone. (gemologyproject.com)

We exhibit a precise and explicit hardness threshold: finding states of energy above the threshold can be done in linear time, while below the threshold this takes exponential time for any algorithm with high probability. (nyu.edu)
The blade of the plastic crusher is refined by special treatment so that it has high hardness and wear resistance. (danslacreuse.fr)
Due to the high hardness, other crushing equipment will reduce the output and efficiency when crushing granite. (danslacreuse.fr)
High levels of hardness will cause scaling in water systems and will prevent foam formation when soap is agitated in water, increasing soap consumption. (vecom-marine.com)
Hardness increases the high‐end frequencies. (dummies.com)
Specifically, the study was directed towards taconite processing since the extreme hardness of taconite results in high noise levels and in considerable maintenance of the processing equipment. (cdc.gov)

There are different Shore Hardness scales for measuring the hardness of different materials. (smooth-on.com)
The many hardness tests listed here measure hardness under different experimental conditions (e.g. indenters made in different sizes, shapes, and materials, and applied with different loads) and reduce their data using different formulae. (efunda.com)
Hardness is defined as a measure of how well materials resist localized deformation, such as impacts, indents, or scratches. (clemex.com)
The heavy loads and robust, spherical indenters of the previous two hardness testing methods were unsuitable for such fragile materials. (clemex.com)
In gemology, we define hardness as the ability to withstand abrasion by other materials. (gemologyproject.com)
Plastic Crushing Machine HDPE PVC Plastic Pipe Crusher This machine is suitable for crushing medium-hardness materials such as limestone, slag, coke, coal and so on in cement, chemical, electric power, metallurgy and other industrial departments. (danslacreuse.fr)
① Jaw crusher: $1, 000/ Set (the lowest price) Used for coarse crushing of rock materials with any hardness. (danslacreuse.fr)
Pseudomonas presence was influenced by water source, factors, such as surface materials, concentration and qual- hardness, free chlorine, and temperature. (cdc.gov)

Would a mineral of a hardness of 9 leave a streak? (pixaria.com)

We provide results showing that our hardness and transferability estimates are strongly correlated with empirical hardness and transferability. (harvard.edu)
LaMotte calcium hardness visual grade Testabs tablets are formulated to dissolve rapidly and produce consistently accurate results. (recreonics.com)

The different Shore Hardness scales measure the resistance of a material to indentation. (smooth-on.com)

Groundwater hardness arises mainly from the solution of limestone into groundwater. (gsi.ie)

For example a material with a Shore hardness of 95A is also a Shore 45D. (smooth-on.com)
It was found from the study that human and animal urine as local ammonia increased the hardness of aluminium alloy material. (eajournals.org)
Animal urine is more effective than human urine on nitriding, nitriding time showed significant effect on hardness of aluminium alloy material. (eajournals.org)
RESUMEN: En lo cotidiano de los Centros de Material y Esterilización (CMEs), se observa que las lavadoras termodesinfectantes sometidas a interven- ciones técnicas para corrección de fallas son liberadas para uso sin evidencia de operación según los parámetros requeridos para realizar limpieza y ter- modesinfección eficientes. (bvsalud.org)

How Do You Physically Measure A Material's Hardness? (smooth-on.com)

A parametric version of the Kannan-Lipton Orbit Problem for linear dynamical systems is studied, showing decidability in the case of one parameter and Skolem-hardness with two or more parameters, and a reduction from the well-knownSkolem problem for linear recurrence sequences is exhibited. (semanticscholar.org)

What is the hardest known mineral with a hardness of 10? (pixaria.com)
Which mineral has a hardness of 6 and shows cleavage? (pixaria.com)

Anatomy12

Organisms4

Diseases5

Chemicals and Drugs81

Analytical, Diagnostic and Therapeutic Techniques and Equipment58

Psychiatry and Psychology1

Phenomena and Processes40

Disciplines and Occupations6

Anthropology, Education, Sociology and Social Phenomena1

Technology, Industry, Agriculture48

Information Science3

Health Care14

Geographicals1

Amsorb: a new carbon dioxide absorbent for use in anesthetic breathing systems. (1/634)

Phase transformations and age-hardening behaviors related to Au3Cu in Au-Cu-Pd alloys. (2/634)

Phase transformation mechanisms in (AuCu)1-xPdx pseudobinary alloys by direct aging method. (3/634)

Reinforcement mechanism of dentin mechanical properties by intracanal medicaments. (4/634)

Isothermal age-hardening behaviour in a multi-purpose dental casting gold alloy. (5/634)

Isothermal age-hardening behaviour in a Au-1.6 wt% Ti alloy. (6/634)

Effects of thermal cycling on dynamic viscoelastic properties of four commercial resins for crown and bridge. (7/634)

Influence of composite inlay/onlay thickness on hardening of dual-cured resin cements. (8/634)

Materials Testing

Composite Resins

Curing Lights, Dental

Water Softening

Dental Materials

Surface Properties

Self-Curing of Dental Resins

Tablets

Halogens

Dental Equipment

Dental Veneers

Dental Polishing

Technology, Dental

Dental Casting Technique

Dental Stress Analysis

Resin Cements

Pliability

Resins, Synthetic

Siloxanes

Dental Porcelain

Inlays

Organically Modified Ceramics

Elastic Modulus

Dental Enamel

Polymerization

Excipients

Energy Drinks

Polymethacrylic Acids

Dental Restoration, Permanent

Maxillofacial Prosthesis

Tooth, Artificial

Dental Restoration Wear

Chemistry, Pharmaceutical

Carbon Compounds, Inorganic

Dental Casting Investment

Titanium

Acrylic Resins

Ceramics

Mastication

Compressive Strength

Denture, Partial, Temporary

Methacrylates

Prosthesis Coloring

Microscopy, Electron, Scanning

Methylcellulose

Water

Microscopy, Scanning Probe

Color

Elasticity

Semiconductors

Powders

Diamond

Drug Compounding

Phase Transition

Tooth Demineralization

Povidone

Zirconium

Immersion

Bisphenol A-Glycidyl Methacrylate

Polymethyl Methacrylate

Silanes

Glass Ionomer Cements

Aluminum Silicates

Nanocomposites

Hoof and Claw

Tensile Strength

Drug Storage

Electron Probe Microanalysis

Analysis of Variance

Metal Ceramic Alloys

Gold Alloys

Mechanical Phenomena

Dentin

Polyurethanes

Tablets, Enteric-Coated

Calcium Carbonate

Tooth Cervix

Microwaves

Solubility

Polymers