Silicon: 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].Organosilicon Compounds: Organic compounds that contain silicon as an integral part of the molecule.Silicon Compounds: Inorganic compounds that contain silicon as an integral part of the molecule.Carbon Compounds, Inorganic: Inorganic compounds that contain carbon as an integral part of the molecule but are not derived from hydrocarbons.Silicon Dioxide: 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.Nanowires: Nanometer-scale wires made of materials that conduct electricity. They can be coated with molecules such as antibodies that will bind to proteins and other substances.Semiconductors: Materials that have a limited and usually variable electrical conductivity. They are particularly useful for the production of solid-state electronic devices.Nanotechnology: The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.Porosity: 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.Transistors, Electronic: Electrical devices that are composed of semiconductor material, with at least three connections to an external electronic circuit. They are used to amplify electrical signals, detect signals, or as switches.Germanium: A rare metal element with a blue-gray appearance and atomic symbol Ge, atomic number 32, and atomic weight 72.63.Silicic Acid: A hydrated form of silicon dioxide. It is commonly used in the manufacture of TOOTHPASTES and as a stationary phase for CHROMATOGRAPHY.Electronics: The study, control, and application of the conduction of ELECTRICITY through gases or vacuum, or through semiconducting or conducting materials. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Silanes: 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.Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.Solar Energy: Energy transmitted from the sun in the form of electromagnetic radiation.Biosensing Techniques: Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.Nanostructures: Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.Molecular Structure: 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.Equipment Design: Methods of creating machines and devices.Micro-Electrical-Mechanical Systems: A class of devices combining electrical and mechanical components that have at least one of the dimensions in the micrometer range (between 1 micron and 1 millimeter). They include sensors, actuators, microducts, and micropumps.Microtechnology: Manufacturing technology for making microscopic devices in the micrometer range (typically 1-100 micrometers), such as integrated circuits or MEMS. The process usually involves replication and parallel fabrication of hundreds or millions of identical structures using various thin film deposition techniques and carried out in environmentally-controlled clean rooms.Silicones: A broad family of synthetic organosiloxane polymers containing a repeating silicon-oxygen backbone with organic side groups attached via carbon-silicon bonds. Depending on their structure, they are classified as liquids, gels, and elastomers. (From Merck Index, 12th ed)Microscopy, Electron, Scanning: 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.Sulfur Compounds: Inorganic or organic compounds that contain sulfur as an integral part of the molecule.Hafnium: Hafnium. A metal element of atomic number 72 and atomic weight 178.49, symbol Hf. (From Dorland, 28th ed)Diatoms: The common name for the phylum of microscopic unicellular STRAMENOPILES. Most are aquatic, being found in fresh, brackish, and salt water. Diatoms are noted for the symmetry and sculpturing of their siliceous cell walls. They account for 40% of PHYTOPLANKTON, but not all diatoms are planktonic.Poa: A plant genus of the family POACEAE that contains the Poa p Ia allergen and allergen C KBGP.Miniaturization: The design or construction of objects greatly reduced in scale.Volatile Organic Compounds: Organic compounds that have a relatively high VAPOR PRESSURE at room temperature.Equipment Failure Analysis: The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.Nanopores: Small holes of nanometer dimensions in a membrane, that can be used as single molecule detectors. The pores can be biological or synthetic.Lab-On-A-Chip Devices: Microdevices that combine microfluidics technology with electrical and/or mechanical functions for analyzing very small fluid volumes. They consist of microchannels etched into substrates made of silicon, glass, or polymer using processes similar to photolithography. The test fluids in the channels can then interact with different elements such as electrodes, photodetectors, chemical sensors, pumps, and valves.Optical Devices: Products or parts of products used to detect, manipulate, or analyze light, such as LENSES, refractors, mirrors, filters, prisms, and OPTICAL FIBERS.Comb and Wattles: Fleshy and reddish outgrowth of skin tissue found on top of the head, attached to the sides of the head, and hanging from the mandible of birds such as turkeys and chickens.Illusions: The misinterpretation of a real external, sensory experience.Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.HydrazinesPhosphoric Acids: Inorganic derivatives of phosphoric acid (H3PO4). Note that organic derivatives of phosphoric acids are listed under ORGANOPHOSPHATES.Hydrocarbons, Acyclic: Organic compounds composed exclusively of carbon and hydrogen where no carbon atoms join to form a ring structure.Radiochemistry: The study of the chemical and physical phenomena of radioactive substances.Hydrazones: Compounds of the general formula R:N.NR2, as resulting from the action of hydrazines with aldehydes or ketones. (Grant & Hackh's Chemical Dictionary, 5th ed)Iodine Isotopes: Stable iodine atoms that have the same atomic number as the element iodine, but differ in atomic weight. I-127 is the only naturally occurring stable iodine isotope.Rubber: A high-molecular-weight polymeric elastomer derived from the milk juice (LATEX) of HEVEA brasiliensis and other trees and plants. It is a substance that can be stretched at room temperature to at least twice its original length and after releasing the stress, retract rapidly, and recover its original dimensions fully.Silicone Elastomers: Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.Silicone Oils: Organic siloxanes which are polymerized to the oily stage. The oils have low surface tension and density less than 1. They are used in industrial applications and in the treatment of retinal detachment, complicated by proliferative vitreoretinopathy.Legislation, Pharmacy: Laws and regulations, pertaining to the field of pharmacy, proposed for enactment or enacted by a legislative body.Palladium: A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.Alkenes: Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)Lewis Bases: Any chemical species which acts as an electron-pair donor in a chemical bonding reaction with a LEWIS ACID.Solvents: Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)Stereoisomerism: The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)

Influence of fibre length, dissolution and biopersistence on the production of mesothelioma in the rat peritoneal cavity. (1/180)

A range of respirable man-made mineral fibres were tested for evidence of carcinogenicity by injection into the peritoneal cavity of male SPF Wistar rats; and differences in carcinogenicity were related to the dimensions and biopersistence of the injected fibres. The fibres tested included an amosite asbestos, a silicon carbide whisker, a special purpose glass microfibre, and a range of other man-made vitreous fibres (MMVFs) and refractory ceramic fibres (RCFs) from the TIMA fibre repository. The injected dose of each was designed as the estimated mass required to contain 10(9) fibres > 5 microns in length, as determined by optical microscopy. The numbers of long fibres (> 15 microns) contained in these doses ranged across fibres from 0.1 x 10(9) to 0.8 x 10(9) fibres; the number of long fibres thinner than 0.95 micron ranged from 0.015 x 10(9) to 0.4 x 10(9). The treatment groups contained between 18 and 24 animals. Animals were killed when they showed signs of debilitation. At autopsy, the diagnosis of mesothelioma was usually obvious macroscopically. Otherwise, histological examination of peritoneal organs was used to search for early tumour development. Judged by median survival time, four of the fibre types, in the doses administered, presented higher mesothelioma activity than amosite asbestos. The other fibres tested were less carcinogenic than the amosite. Only a ceramic material derived by extreme heating to simulate the effect of furnace or oven conditions, produced no mesotheliomas. Attempts were made, using regression models, to relate these differences to fibre dimensions and to measures of durability from separate experiments. The results pointed principally to a link with the injected numbers of fibres > 20 microns in length and with biopersistence in the rat lung of fibres longer than 5 microns. Improved quantification of the relative importance of fibre dimensions and biopersistence indices requires experimentation with a range of doses.  (+info)

Depletion of glutathione and ascorbate in lung lining fluid by respirable fibres. (2/180)

OBJECTIVE: The use of synthetic vitreous fibres has increased along with a decline in the utilisation of asbestos. There remains concern that these synthetic fibres pose a health risk to workers because of the generation of respirable fibres which can enter the lung and cause adverse health effects. An improved understanding of the mechanism of fibre pathogenicity should allow more rational short-term testing regimes for new fibres as they are developed. We hypothesised that carcinogenic fibres have greater free radical activity compared with non-carcinogenic fibres and that they contribute to disease by causing oxidative stress in the lung. We examined a panel of respirable fibres, designated as being carcinogenic or non-carcinogenic based on previous animal studies for ability to deplete antioxidants from lung lining fluid. METHODS: On the basis of inhalation studies, a panel of fibres was divided into three carcinogenic fibres-amosite asbestos, silicon carbide, and refractory ceramic fibre 1 (RCF1) and three non-carcinogenic fibres-man-made vitreous fibre 10 (a glass fibre MMVF10), Code 100/475 glass fibre, and refractory ceramic fibre 4 (RCF4). We measured the levels of glutathione (GSH) and ascorbate, two antioxidants present in lung lining fluid (LLF) after fibre treatment. All of the experiments were carried out at equal fibre number. RESULTS: Fibres had the ability to deplete both GSH and ascorbate from both LLF and pure solutions, an effect which was fibre number dependent. The greatest depletion of antioxidants was observed with the two non-carcinogenic glass fibres, and this effect was observed when A549 lung epithelial cells were treated with fibres. CONCLUSIONS: Our results show that antioxidant depletion in cell free solution and lung lining fluid solely is not a simple indicator of the ability of fibres to cause lung pathology and that other biological events in the lung are involved.  (+info)

Magnetometric evaluation for the effects of silicon carbide whiskers on alveolar macrophages. (3/180)

Alveolar macrophages are thought to play an important role in fibrogenesis in the lungs caused by various types of exposure to dust. In this experiment, we evaluated the effect of silicon carbide whiskers (SiC) on alveolar macrophages mainly by unique magnetometry and also by established methods such as lactate dehydrogenase (LDH) activity, apoptosis measurement and morphological observations. Alveolar macrophages obtained from Syrian golden hamsters by bronchoalveolar lavages were exposed in vitro to Fe3O4 for 18 hours as an indicator for magnetometry and SiC for experiments. A rapid decrease of the remanent magnetic field, so called "relaxation", was observed after cessation of an external magnetic field in macrophages phagocytizing Fe3O4 alone, while relaxation was delayed in those concurrently exposed to SiC. Release of LDH from SiC-exposed macrophages into the medium was not significantly higher than the controls, but it increased dose-dependently. Apoptosis was recognized in macrophages exposed to 60 micrograms/ml of SiC by the DNA ladder detection method and morphological observations. Electron microscopic examination revealed irregular forms of nuclei and organellas in macrophages exposed to SiC. Magnetometry, LDH release and electron microscopic observation indicated mild cytotoxicity of SiC to alveolar macrophages.  (+info)

Origin of nanomechanical cantilever motion generated from biomolecular interactions. (4/180)

Generation of nanomechanical cantilever motion from biomolecular interactions can have wide applications, ranging from high-throughput biomolecular detection to bioactuation. Although it has been suggested that such motion is caused by changes in surface stress of a cantilever beam, the origin of the surface-stress change has so far not been elucidated. By using DNA hybridization experiments, we show that the origin of motion lies in the interplay between changes in configurational entropy and intermolecular energetics induced by specific biomolecular interactions. By controlling entropy change during DNA hybridization, the direction of cantilever motion can be manipulated. These thermodynamic principles were also used to explain the origin of motion generated from protein-ligand binding.  (+info)

Neutron reflection from a dimyristoylphosphatidylcholine monolayer adsorbed on a hydrophobised silicon support. (5/180)

Neutron specular reflection has been used to study the structure of a monolayer of dimyristoylphosphatidylcholine (DMPC) deposited using the Langmuir-Blodgett technique onto a silicon oxide substrate. A self-assembled monolayer of octadecyltrichlorosilane with a deuterated alkyl chain (d-OTS) had been previously bonded onto this silicon oxide substrate which rendered it hydrophobic. In the system under study, the alkyl chains of the phospholipid were found to penetrate extensively into the d-OTS layer with the mixed chain region (d-OTS and DMPC) having a total thickness of 30.5 A. This mixed region was divided into two halves for analysis; the 'lower half' (nearest to the substrate surface) was found to comprise anchored d-OTS chains mixed with the lipid chains in the volume ratio approx. 0.60:0.35. The corresponding volume ratio in the 'upper half' of this region was determined to be approx. 0.50:0.40. The thicknesses of these regions were found to be 17.9 A (incorporating approx. 6% solvent) and 12.6 A (incorporating approx. 9% solvent) for the lower and upper halves respectively. The DMPC head groups were found to be confined to the most external layer (furthest away from the silicon substrate). This layer was found to have a thickness of 9.4 A and included a small fraction of the lipid alkyl chains with approx. 47% solvent.  (+info)

Short term effect of silicon carbide whisker to the rat lung. (6/180)

We studied the short-term effect of silicon carbide whisker (SiCW) in vivo by instillation and inhalation to the rat lung. SiCW was instilled low dose (2 mg/0.5 ml saline) or high dose (10 mg/ 0.5 ml) intratracheally into the lungs of 25 rats. SiCW was also inhaled to another 25 rats at the average concentration of 10.4 mg/m3 for 1 month. In instillation study, the lung had focal alveolitis with the destruction of alveolar wall especially at 3 days after the instillation, and the lesion remained as an aggregated foci of SiCW at 6 months. The 'inflammation-score' of the instilled group by point counting method of the specimen correspondingly decreased gradually. In inhalation group, a minimum inflammatory change was observed. Collagen deposition in the aggregated foci of SiCW with accumulated alveolar macrophages and neutrophils was not progressive during the observed period. These findings suggest that SiCW may cause a minor effect to the rat lung in 6 months after exposure.  (+info)

Cancer incidence among workers in the Norwegian silicon carbide industry. (7/180)

The presence of silicon carbide (SiC) fibers in the SiC smelter work environment has suggested a possible cancer hazard. The authors studied cancer incidence among 2,620 men employed for more than 6 months in three Norwegian SiC smelters. Follow-up from 1953 to 1996 revealed an overall excess risk of lung cancer (standardized incidence ratio = 1.9, 95% confidence interval (CI): 1.5, 2.3) and an elevated risk of stomach cancer (standardized incidence ratio = 1.5, 95% CI: 1.1, 2.0). Both standardized incidence ratio and Poisson regression analyses showed that lung cancer risk increased according to cumulative exposure to total dust, SiC fibers, SiC particles, and crystalline silica. The standardized incidence ratio for the upper SiC fiber exposure category was 3.5 (95% CI: 2.1, 5.6) when exposure was lagged by 20 years, while the Poisson regression analysis showed a rate ratio of 4.4 (95% CI: 2.1, 9.0). Smoking did not seem to be an important confounder. The excess risk of lung cancer may be explained by exposure to SiC fibers, but a strong correlation between the different exposures made it difficult to distinguish between them.  (+info)

Silicon-based biosensors for rapid detection of protein or nucleic acid targets. (8/180)

BACKGROUND: We developed a silicon-based biosensor that generates visual, qualitative results or quantitative results for the detection of protein or nucleic acid targets in a multiplex format. METHODS: Capture probes were immobilized either passively or covalently on the optically coated surface of the biosensor. Intermolecular interactions of the immobilized capture probe with specific target molecules were transduced into a molecular thin film. Thin films were generated by enzyme-catalyzed deposition in the vicinity of the surface-bound target. The increased thickness on the surface changed the apparent color of the biosensor by altering the interference pattern of reflected light. RESULTS: Cytokine detection was achieved in a 40-min multiplex assay. Detection limits were 4 ng/L for interleukin (IL)-6, 31 ng/L for IL1-beta, and 437 ng/L for interferon-gamma. In multianalyte experiments, cytokines were specifically detected with signal-to-noise ratios ranging from 15 to 80. With a modified optical surface, specificity was also demonstrated in a nucleic acid array with unambiguous discrimination of single-base changes in a 15-min assay. For homozygous wild-type and homozygous mutant samples, signal-to-noise ratios of approximately 100 were observed. Heterozygous samples yielded approximately equivalent signals for wild-type and mutant capture probes. CONCLUSIONS: The thin-film biosensor allows rapid, sensitive, and specific detection of protein or nucleic acid targets in an array format with results read visually or quantified with a charge-coupled device camera. This biosensor is suited for multianalyte detection in clinical diagnostic assays.  (+info)

  • Researchers in the laboratory of Caltech's Frances Arnold discuss how they persuaded nature to make silicon-carbon bonds. (
  • Following a few tweaks, heme proteins can efficiently catalyze the formation of carbon-silicon bonds, which are not found in any known biological molecules, nor capable of being created through any existing biological processes. (
  • However, existing methods for synthesizing carbon-silicon bonds have limitations, requiring expensive trace metals or sometimes requiring low temperatures to function optimally, for example. (
  • A new study is the first to show that living organisms can be persuaded to make silicon-carbon bonds-something only chemists had done before. (
  • Currently, these products are made synthetically, since the silicon-carbon bonds are not found in nature. (
  • This news video explains how Caltech researchers persuaded nature to make silicon-carbon bonds for the first time. (
  • No living organism is known to put silicon-carbon bonds together, even though silicon is so abundant, all around us, in rocks and all over the beach," says Jennifer Kan, a postdoctoral scholar in Arnold's lab and lead author of the new study. (
  • The researchers' first step was to find a suitable candidate, an enzyme showing potential for making the silicon-carbon bonds. (
  • That protein, called cytochrome c, normally shuttles electrons to other proteins, but the researchers found that it also happens to act like an enzyme to create silicon-carbon bonds at low levels. (
  • Compounds which contain a piperidine ring, i.e., a six-membered hetero ring consisting of one ring nitrogen and five ring carbons with no double bonds between ring members. (
  • First page The Reactivity with Alkali of Chlorine-Carbon Bonds Alpha, Beta and Gamma to Silicon Leo H. Sommer, Edwin Dorfman, Gershon M. Goldberg, Frank C. Whitmore J. Am. Chem. (
  • We wanted to know, and discovered that enzymes that forge carbon-silicon bonds could be evolved in a test tube . (
  • Scientists at Caltech have "bred" a bacterial protein with the ability to make silicon-carbon bonds, with applications in several industries - something only chemists could do before. (
  • The "killer app" for Si would presumably be very rare, although I wonder if someone has taken advantage of a displaceable group on silicon to form strong Si-O bonds with an enzyme to shut it down. (
  • The cyclic compound which best mimics the action of the natural pheromones presumably has a conformation similar to that which the pheromone adopts when bound to the receptor site. (
  • Addition of alkali to the β-substituted compound on the other hand leads to an elimination reaction with liberation of ethylene. (
  • Although many of the techniques applied by the team are already used in silicon fabrication, they have only rarely been used to make compound semiconductor transistors. (
  • But when you are talking about integrating billions of tiny transistors onto a chip, then we need to completely reformulate the fabrication technology of compound semiconductor transistors to look much more like that of silicon transistors,' del Alamo says. (
  • The produced polysilicon is used as wafers in large amounts by the photovoltaic industry for conventional solar cells made of crystalline silicon and also by the semiconductor industry. (
  • The creation of an impurity into silicon as a semiconductor boosts it into comprehensive conduction. (
  • Monochlorides of esters of phospheric acid also react with hexamethyldisilazane under heterocyclic fission of the Si-N-compound, while the reaction of trimethyl-N-methylamino-silane results in the substitution of the H-atom attached to the N-atom without any fission of the Si-N-compound. (
  • The alpha-silicon effect is the destabilizing effect of a silicon atom (relative to a carbon atom) next to a reaction center with a partial positive charge. (
  • Removing silicon species from hydrocarbon solvents such as cyclohexane. (
  • The present invention relates to a process for removing silicon compounds from hydrocarbon solvents. (
  • More particularly, the invention relates to a process for removing residual silicon species from polymerization solvents. (
  • Quartz forms the pure shape of silicon oxide and is also utilised in cosmetic sunglasses who are used by engineering. (
  • The silicon rubber coated glass fiber cloth is made of high-temperature resistant, corrosion resistant and high strength glass fiber cloth which is rolled or soaked with organic silicon rubber. (
  • The silicon rubber coated glass fiber cloth includes two types of single side and double sides. (
  • Compared with the common coated fabrics, the silicon rubber coated glass fiber cloth is characterized by unique high-temperature resistance, permeability resistance, excellent weather aging resistance, softness and toughness. (
  • The silicon rubber coated glass fiber cloth is a new composite material-made product with high performance and multiple functions. (
  • The silicon rubber cloth cannot be used in places where SO2 containing flue gas and vapor exists. (
  • 3. Corrosion resistance: the silicon rubber coated glass fiber cloth can be used as internal-external corrosion resistant coatings of a pipe, and can achieve quite good corrosion resistance and high strength, so that the silicon rubber coated glass fiber cloth is an ideal corrosion resistant material. (
  • 4. Other fields: the silicon rubber coated glass fiber film structural material can be applied in fields such as construction sealing materials, a high-temperature corrosion resistant conveying belt, packaging materials, etc. (
  • Bluestar Silicones and Basoğlu Kablo join forces to create a rubber compounding center in Turkey to serve customers with technical products adapted to local requirements. (
  • the blocked mercaptosilanes can be used in rubber compounds. (
  • A method of and system for removing silicon from a high temperature liquid sodium coolant system for a nuclear reactor. (
  • The sodium is cooled to a temperature below the silicon saturation temperature and retained at such reduced temperature while inducing high turbulence into the sodium flow for promoting precipitation of silicon compounds and ultimate separation of silicon compound particles from the liquid sodium. (
  • The functionalized silicon compounds may be covalently attached to surfaces to form functionalized surfaces which may be used in a wide range of different applications. (
  • Epic Resins offers an extensive range of potting compounds to accommodate many applications. (
  • While silicone potting compounds have some advantages, polyurethanes tend to work better for many applications . (
  • Epic S7325 is a two-component polyurethane compound specifically designed for potting/casting applications that require low hardness, convenient volumetric mix ratio and short working times. (
  • EPIC S7325 is useful for applications requiring a re-enterable compound. (
  • This strategic move comes after Bluestar Silicones announced the investment of 15M€ in new state of the art HCR technology to bolster its presence and market share in highly demanding HCR applications. (
  • Since the discovery of hydroformylation by O. Roelen in 1938, catalytic applications have paved the way of organometallic compounds in industry. (
  • The absolute concentration associated with the term 'virtual removal' is not defined in the government documents, but if it is set at a low level, resulting legislation could have the effect of removing silicones from nearly all applications and markets in Canada--medical devices excepted. (
  • The partnership will enhance GCL-Poly's overall competitiveness by diversifying the silicon products, better serving its main business, and meeting market demand,' said Zhu Gongshan, Chairman of GCL-Poly. (
  • Common products contain complex mixtures of Endocrine-disrupting compounds and asthma-related compounds. (
  • This invention relates to novel room temperature curable compositions comprising a hydroxyl containing organic thermoplastic polymer and an aminoorganosilicon acylamino compound, as well as to the crosslinked products derived from said compositions. (
  • It has now been discovered that room temperature curable polymer compositions can also be easily prepared at room temperature by simply mixing a hydroxyl containing organic thermoplastic polymer with certain hydrolyzable aminoorganosilicon acylamino compounds without also resulting in undesirable by-products. (
  • Diversified application of Silicon-centred systems in businesses, consumer electronics and personal computers, products in the home, textiles, construction, and cars will make it one of many superb crucial elements inside globe now. (
  • These 3 silicones are used in their own right, particularly in personal care products, either individually (previously [D.sub.was most commonly used, but over the last decade has been supplanted by [D.sub. or as mixtures (cyclomethicones). (
  • She continued her research with several additional studies including a publication in 1981 titled " Silicon: a requirement in bone formation independent of vitamin D 1 " [ 15 ]. (
  • Mechanistic studies of hydrosilylation using an optically active silane substrate, R-(+)-methyl-(1-naphthyl)phenylsilane, proceeded with predominant stereochemical retention at silicon, consistent with a carbonyl activation pathway. (
  • The also preferred are those silicon compounds in which a is 0, c is 3, R12 is branched alkyl or cycloalkyl, containing optionally a heteroatom, and R13 is methyl, for example, cyclohexyltrimethoxysilane and the like. (
  • Compound (21) was also obtained using the same method from 2-(5-acetoxypentyl)-3-methyl-cyclohexan-one (63). (
  • The also preferred are those silicon compounds in which a is 0, c is 3, R 12 is branched alkyl or cycloalkyl, containing optionally heteroatom, and R 13 is methyl, for example, cyclohexyltrimethoxysilane and the like. (
  • The process comprises contacting the hydrocarbon solvent with sulfuric acid in an amount sufficient to phase separate the silicon species and removing at least 20% by weight of the residual silicon species from the hydrocarbon solvent. (
  • Thus, it would be difficult for a silicon-based life-form to achieve all of the wonderful regulating and recognition functions that carbon-based enzymes perform for us. (
  • They give an excellent overview of current research into many areas of tin and silicon, encompassing both inorganic and organometallic derivatives and fundamental and applied studies. (
  • Pyrolysis of SiBr4 followed by treatment with ammonia yields silicon nitride (Si3N4) coatings, a hard compound used for ceramics, sealants, and the production of many cutting tools. (
  • Carlisle concluded that silicon is important as an initiator of mineralization because silicon is highly concentrated in immature osteoid but declines as calcium content rises in mature bone. (