Higher alkanes alkanes. Medical search. Frequent questions

His work has resulted in new methods for the conversion of straight chain hydrocarbons (when used in combustion engines these have very low octane number and they are also difficult to degrade biologically) into branched hydrocarbons that have high octane numbers and are more easily biodegradable. (nobelprize.org)
Vaseline is a semisolid mixture of mostly highly branched, high molecular weight aliphatic hydrocarbons having high viscosity and some degree of thyxotropy. (yarchive.net)
The formula for acyclic saturated hydrocarbons (i.e., alkanes ) is C n H 2 n +2 . (wikipedia.org)
: 625 As given in the example of 3-methylhexane and its higher homologues , branched hydrocarbons can be chiral . (wikipedia.org)
This video gives an overview of hydrocarbons and alkanes. (topperlearning.com)
Jet fuels consist of four families of hydrocarbons: n-alkanes, iso-alkanes, cycloalkanes, and aromatics. (biofuels-news.com)
Alkanes are the simplest family of hydrocarbons - compounds containing carbon and hydrogen only. (shout.education)
The SPME fiber coupled with gas chromatograph (GC) is then used to extract polycyclic aromatic hydrocarbons (PAHs), anilines, phenols, and alkanes from standard and real water samples, and exhibits high selectivity for PAHs. (who.int)

The physical properties of alkenes and alkynes are generally similar to those of alkanes or cycloalkanes with equal numbers of carbon atoms. (britannica.com)
Hydrogenation is used to prepare alkanes and cycloalkanes and also to change the physical properties of highly unsaturated vegetable oils to increase their shelf life. (britannica.com)
What are Alkanes and Cycloalkanes? (shout.education)
Cycloalkanes have boiling points which are about 10 - 20 K higher than the corresponding straight chain alkane. (shout.education)
What follows applies equally to alkanes and cycloalkanes. (shout.education)

Still, the mixture has to contain a high percentage >of aromatics. (yarchive.net)
High sensitivity mode works well for compounds such as halogenated alkanes and substituted aromatics, as well as mixtures with one or more compound of low concentration. (vernier.com)
Gasoline vapors contain about 90% alkanes and 2% aromatics (0.9% benzene). (cdc.gov)

Molecular Simulation Study on the Density Behavior of n-Alkane/CO2 Systems. (acs.org)
Hydrogenation is the addition of molecular hydrogen (H 2 ) to a multiple bond, which converts alkenes to alkanes. (britannica.com)
The latter more reliably affords high molecular-weight polymers, but only applies to certain monomers. (wikipedia.org)
In the soil profiles, the d 13 C n -alk values exhibit a high degree of variability across the higher molecular weight homologues (C 27 -C 33 ). (atlas.jp)
As the d 13 C values of higher molecular weight homologues (C 27 -C 33 ) have been primarily used to estimate the relative abundance of C 3 and C 4 plants in the past, significant inter-homologue variations in the d 13 C n -alk values can result in erroneous paleovegetational interpretations. (atlas.jp)
Fischer Tropsch wax is mainly composed of linear and saturated high-carbon alkanes with molecular weight of 500-1000. (myerswax.com)
According to the needs, alkanes with different chain lengths can be synthesized in the battle process to change the molecular weight of the final product, so as to form a series of products. (myerswax.com)
The higher the molecular weight (the greater the number of carbons), the higher the boiling point. (topperlearning.com)
That's why the boiling points of the alkanes increase with molecular size. (shout.education)
Even though this approach is conceptually applicable to non-volatile and high molecular weight organics as well, it is more challenging to predict the other PBPK model parameters required for modelling the kinetics of these chemicals (particularly tissue diffusion coefficients, association constants for binding and oral absorption rates). (cdc.gov)

Alkenes and alkynes generally have physical properties similar to those of alkanes. (topperlearning.com)

These include lipids and higher alkanes that are insoluble in water but are soluble in nonpolar, organic solvents. (grandviewresearch.com)
Alkanes are virtually insoluble in water, but dissolve in organic solvents. (shout.education)

what is the effect of melting point and boiling point on branching in alkanes , alkenes and alkynes? (topperlearning.com)

A prime example was the accident on the Deepwater Horizon drilling platform, which caused severe environmental damage in the Gulf of Mexico due to the toxic effects of crude oil compounds like liquid alkanes. (phys.org)
The microbial community was cultivated in a variety of liquid alkanes, here a hexane culture. (phys.org)
In the Bremen laboratories the researchers prepared cultures with liquid alkanes and allowed them to grow anaerobically, i.e., without oxygen, at high temperatures (70 degrees Celsius). (phys.org)
The liquid alkanes are good solvents for many other covalent compounds. (shout.education)

Higher alkanes are alkanes having nine or more carbon atoms. (wikipedia.org)
Alkanes from nonane to hexadecane (those alkanes with nine to sixteen carbon atoms) are liquids of higher viscosity, which are less suitable for use in gasoline. (wikipedia.org)
Alkanes with a chain length of approximately 35 or more carbon atoms are found in bitumen (asphalt), used (for example) in road surfacing. (wikipedia.org)
Most of us can recall from our high school chemistry courses that many so called inorganic compounds, like for example ordinary table salt, NaCl, could be regarded as built up from atoms or groups of atoms that are electrically charged. (nobelprize.org)
Alkanes are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds without any cycles. (absoluteastronomy.com)
The reaction occurs at high temperatures because Cl 2 molecules can dissociate to form Cl atoms by absorbing thermal energy. (purdue.edu)
If two alkanes have the same formula weight (differing only in connectivity of atoms due to branching), the one that has more extensive branching has the lower boling point because the branching prevents the molecules from being packed together as tightly as occurs in a straight chain. (topperlearning.com)
All the alkanes with 4 or more carbon atoms in them show structural isomerism. (shout.education)

Ni or Co addition to Pt increased the carbon conversion while keeping the H 2 turnover high. (hindawi.com)
Measurements and Modeling of Volumetric and Phase Behavior of Carbon Dioxide + Higher Alkanes: CO2 + n-Pentadecane at Temperatures 313 to 410 K and Pressures up to 77 MPa. (acs.org)
In soil, the distribution and carbon isotopic composition of n -alkane (d 13 C n -alk ) is extremely source-specific. (atlas.jp)
Alkanes are highly stable compounds of carbon and hydrogen. (phys.org)

The concentrations of n -alkanes varied between 2.43 and 25.82 µg g -1 . (scielo.br)
The highest relative concentrations of volatile compounds were found on the plastic materials, the lowest from materials such as glass, cardboard, and ceramic. (cdc.gov)
Other groups of compounds called alkanes, like propane and butane, were also present in high concentrations. (agu.org)
Emissions have, for the most part, increased over the 20th century, leading to higher aerosol concentrations and tropospheric ozone levels as industrial activities and fossil fuel consumption increased. (copernicus.org)
In the six-cycle experiments (at the rear instructor location), OSB-fueled fires produced the highest median concentrations of benzene and 1,3 butadiene, plywood-fueled fires produced the highest total polycyclic aromatic hydrocarbon (PAH) concentrations, particle board-fueled fires produced the highest methyl isocyanate concentrations, and pallet-fueled fires produced the highest hydrogen chloride concentrations. (cdc.gov)
However, it was found that exposure can be reduced by moving firefighters and instructors lower in the compartment and/or by moving the instructor in charge of ventilation from the rear of the structure (where highest concentrations were consistently measured) to an outside position. (cdc.gov)

Although alkanes like propane and butane aren't directly harmful to humans, they can cause their own brand of mischief. (agu.org)
Chem 350 Jasperse Ch. 3 Notes 5 Conformations of Butane and Longer Alkanes (3.8) CH3CH2-CH2CH3 is more complex. (docslib.org)
This is an introductory page about alkanes such as methane, ethane, propane, butane and the rest. (shout.education)

However, due to the uncontrollable reactivity of alkyl radicals, the production of desired alkanes was characterized by low selectivity. (greencarcongress.com)
Rationally controlling the conversion of radical intermediates for preferential hydrogen termination is the key to high selectivity in obtaining alkane products. (greencarcongress.com)
Although both methods have their advantages and limitations, the former approach has been used to synthesize a broader range of organic substances as the latter is limited by several factors, such as poor selectivity and high energy cost. (rsc.org)
In nature, there exist various enzymes that are capable of oxidizing target substrates with high selectivity. (rsc.org)

alkyldienes, alkenes, and alkanes were detected from the marking of high density polyethylene bottles. (cdc.gov)
As alkenes can polymerize in somewhat straightforward radical reactions, they form useful compounds such as polyethylene and polyvinyl chloride (PVC), [3] which are produced in high tonnages each year [3] due to their usefulness in manufacturing processes of commercial products, such as piping, insulation and packaging. (wikipedia.org)

However the higher melting points of these alkanes can cause problems at low temperatures and in polar regions, where the fuel becomes too thick to flow correctly. (wikipedia.org)
Current methods of industrial hydrogen production used in petroleum refineries require high temperatures, about 800 K in the case of naphtha reforming [ 1 ] and 1200 K for methane steam reforming [ 2 ]. (hindawi.com)
This can be explained by noting that alkanes react with halogens at high temperatures or in the presence of light to form alkyl halides. (purdue.edu)
In their latest study, the researchers have demonstrated that archaea use a previously unknown mechanism to degrade liquid petroleum alkanes at high temperatures without the presence of oxygen. (phys.org)
The special geological conditions that exist here include high temperatures, liquid crude-oil components, and an anaerobic environment at shallow sediment depths, all of which are normally only found in deep-lying oil reservoirs which are difficult for scientists to access. (phys.org)

Mixtures of the normal alkanes are used as boiling point standards for simulated distillation by gas chromatography. (wikipedia.org)

This video explains IUPAC nomenclature, isomerism in alkanes and preparatio. (topperlearning.com)

Two new organometallic alkane complexes, Cp ‡ Re(CO) 2 (alkane) ( alkane = cyclopentane , n -heptane ) have been characterized by IR spectroscopy following irradiation of Cp ‡ Re(CO) 2 (N 2 ) and their rate constants for reaction with CO have been determined. (rsc.org)
Cyclic Alkanes: names start in "cyclo" ( cyclopentane , cyclooctane , etc.) 7. (docslib.org)

However, most established catalytic systems require harsh operating conditions (i.e., high temperature and pressure) and excessive hydrogen consumption. (greencarcongress.com)
An overview of aqueous-phase catalytic processes for production of hydrogen and alkanes in a bio refinery has been shown by Huber and Dumesic [ 8 ]. (hindawi.com)

Many solid alkanes find use as paraffin wax, used for lubrication, electrical insulation, and candles. (wikipedia.org)
On the other hand, microcrystalline wax has a higher melting point and is comparatively more flexible than paraffin and therefore, is used in large-scale industrial applications apart from the cosmetic industry. (grandviewresearch.com)
Mineral oil, or paraffin oil, is a mixture of higher alkanes from a mineral source, such as petroleum. (drugbank.com)
The produced oil from Ca NguVang field has a high concentration of paraffin, which tends to cause wax deposition in pipes. (scirp.org)

Thus, the aim of this study is to evaluate the origin of organic matter in Rodrigo de Freitas Lagoon, an eutrophic, coastal and chocked lagoon in Rio de Janeiro, Brazil, through the determination of n -alkanes and sterols compounds in the upper two centimeters of sediment and compare these data with methane ebullitive flux. (scielo.br)
We conclude that the organic matter reaching Rodrigo de Freitas Lagoon through the rivers discharge added or enriched with irregular sewage input and petroleum derivates are the main source of eutrophication and generate higher methane emissions to the atmosphere. (scielo.br)
It has been recently reported that, compared to pre-industrial period, methane levels were 150% and 257% higher in 2011 and 2016, respectively. (scielo.br)
Methane is part of a homologous series known as the alkanes , which contain single bonds only. (wikipedia.org)

1990. Conversion of alkanes into gasoline on ZSM-5 zeolite catalysts. (cdc.gov)
By the end of the 1970s, regulations provided for the use of high-octane gasoline, on sale in France, Italy, Germany and England. (f1technical.net)
In addition, they may be exposed to higher levels than adults in the same location because of their short stature and the higher levels of gasoline vapor found nearer to the ground. (cdc.gov)

2020) "Enhanced photocatalytic alkane production from fatty acid decarboxylation via inhibition of radical oligomerization. (greencarcongress.com)

Alkanes live on the order of hours to days, while carcinogens like benzene live for about a day. (agu.org)

This quiz focuses on the organic compounds called Alkanes. (brainmass.com)

Branched isomers for acyclic alkanes still have CNH2N+2 6. (docslib.org)
By the time you get 17 carbons into an alkane, there are unbelievable numbers of isomers! (shout.education)

This suggests that the observed variation in the d 13 C n -alk values in the soil is a result of microbial degradation of n -alkanes during its transfer from leaves to soil. (atlas.jp)

This video explains physical properties of alkanes and substitution reactio. (topperlearning.com)

In general, terrestrial higher plants are primary producers of long-chain n -alkanes (C 27 -C 33 ) while short-chain n -alkanes (C 14 -C 20 ) are mainly contributed from microorganisms with distinct d 13 C n -alk values. (atlas.jp)
In the presence of oxygen, microorganisms can rapidly break down many components of crude oil, among others alkanes. (phys.org)

Microcrystalline waxes provide high diversity in terms of physical and thermal properties. (grandviewresearch.com)

I want to get the latest chemistry news from C&EN in my inbox every week. (acs.org)
Free-radical halogenation of alkanes provides us with another example of the role of atom-transfer reactions in organic chemistry. (purdue.edu)

a large isotopic shift of the 1 H resonance at δ = −2.44 upon partial deuteration of the alkane (Δ δ = 1.77 ppm), a large 1 J C-H (114 Hz) and a large negative 13 C chemical shift ( δ = −33.8). (rsc.org)

1981. Analysis and environmental fate of Air Force distillate and high density fuels. (cdc.gov)
All fuels other than particle board produced similarly high levels of formaldehyde at the rear instructor location. (cdc.gov)
Air sampling did not identify any clear differences between training fires from burning solid wood pallets and those that incorporate wood-based sheet products for this commonly employed fuel arrangement with fuels mounted high in the compartment. (cdc.gov)

The other crystallizing dish picks up the characteristic color of a dilute solution of bromine because this reagent doesn't react with alkanes under normal conditions. (purdue.edu)

Photolysis of CpRe(CO) 2 (N 2 ) to form the organometallic alkane complex occurs with a much higher yield than for CpRe(CO) 3 . (rsc.org)

Alkenes react with a much richer variety of compounds than alkanes. (britannica.com)

A detailed mechanistic study of the reactions of VO+ and VO2+ with alkanes and their potential oxidation products like alkenes and alcohols is complemented by a derivation of formerly unknown thermochemical data for VO2Ho/+, VO3H and VO3H2+. (scheringstiftung.de)
The multi-bed sorbent in the thermal desorption tubes was overwhelmed by high-levels of alcohols, making them unsuitable for quantifying low-level VOC exposures in healthcare settings. (cdc.gov)

A coupling reaction in which two alkyl halides reacted with sodium metal in dry ether to form higher alkanes is the Wurtz reaction. (bartleby.com)
Write a suitable mechanism for the cleavage of butyl isopropyl ether with HI. (brainmass.com)
Write a suitable mechanism for the cleavage of butyl isopropyl ether with HI at 100 degrees Celsius to form exclusively isopropyl alcohol and 1-iodobutane. (brainmass.com)
The conversion of tert-butylchloride to tert- butyl ethyl ether to insure the highest possible yield of the ether . (brainmass.com)

It is easy to penetrate into the high viscosity macromolecular chain, which can significantly reduce the melt viscosity. (myerswax.com)

Review of Density Measurements and Predictions of CO2-Alkane Solutions for Enhancing Oil Recovery. (acs.org)
Density and Volumetric Behavior of Binary CO2 + n-Decane and Ternary CO2 + n-Decane + Naphthalene Systems at High Pressure and High Temperature. (acs.org)

Researchers led by Prof. WANG Feng at the Dalian Institute of Chemical Physics (DICP) of the Chinese Academy of Sciences have reported that photocatalytic decarboxylation is an efficient alternate pathway for converting biomass-derived fatty acids into alkanes under mild conditions of ambient temperature and pressure. (greencarcongress.com)
Schematic representation of photocatalytic decarboxylation strategy for alkane production from biomass-derived fatty acids. (greencarcongress.com)
Production of these alkanes from renewable biomass-such as biomass-derived fatty acids instead of fossil resources-could contribute significantly toward developing a sustainable energy supply. (greencarcongress.com)
These results show that C n-1 alkanes can be obtained from biomass-derived C 12 -C 18 fatty acids in high yields (greater than or equal to 90%) under mild conditions (30 °C, H 2 pressure less than or equal to 0.2 MPa) with 365 nm LED irradiation. (greencarcongress.com)

The high gloss formula system provides a smooth durable top coat which will approximately cover up to 18m2 per litre. (jewson.co.uk)

A dinitrogen precursor allows for the use of longer wavelength irradiation and the generation of a higher concentration of the alkane complex following each laser pulse. (rsc.org)
The concentration of long-chain n -alkanes (C 27 -C 33 ) within the soil profiles decreases with depth, indicating a significant loss of biomarkers during soil-forming processes. (atlas.jp)

The reaction between an alkane and one of the halogens (F 2 , Cl 2 , Br 2 , or I 2 ) can be understood by turning to a simpler example. (purdue.edu)
The TS of a reaction step more closely resembles the higher energy partner (reactant or product of that step). (utexas.edu)

Hence, the distribution and d 13 C values of n -alkane in sediments have been primarily used to characterize the source(s) of organic matter in a given depositional environment as well as to gain insight into paleoenvironmental conditions. (atlas.jp)

The demand for the product is anticipated to be driven by the growing demand in various industries because of its superior properties such as high gloss, good water repellency, and outstanding chemical resistance. (grandviewresearch.com)
By clicking "Subscribe" you agree to receive C&EN's newsletter and provide permission for American Chemical Society (ACS Publications and C&EN) to email you in accordance with the ACS Privacy Policy . (acs.org)
The chemical has fine crystalline structure, high melting point, narrow melting point range, low oil content, low penetration, low melting degree and low melting. (myerswax.com)

By contrast, high-temperature sites without seepage harbor mainly novel taxa belonging to phyla that are widespread in cold subseafloor sediment. (nature.com)
For instance, you can make a high temperature bearing grease from engine oil combined with tallow, stearic acid and caustic soda. (yarchive.net)
Notice that the first four alkanes are gases at room temperature. (shout.education)
Beyond that, the SPME fiber has high strength, large surface area, good stability at high temperature and in acid and alkali solutions, and long service life, making it have strong application potentials in the selective extraction of PAHs from complex samples at trace levels. (who.int)

Modification of Higher Alkanes by Nanoparticles to Control Light Propagation in Tapered Fibers. (nih.gov)
However, very little is known about post-depositional modification of plant-derived long-chain n-alkanes within the soil. (atlas.jp)

When alkanes mingle with other chemicals in our atmosphere, they form new chemicals like ozone. (agu.org)

Thus, best-performing catalysts have high Pt surface areas per unit catalyst mass. (hindawi.com)
Due to the difficulties of achieving and maintaining a high metal dispersion, most current Pt catalysts for APR have great Pt loads and high associated costs. (hindawi.com)

Chem 350 Jasperse Ch. 3 Notes 2 Nomenclature of Alkanes (Sections 3.3-4) Systematic IUPAC Rules for Branched and Substituted Alkanes 1. (docslib.org)

Alkanes from hexadecane upwards form the most important components of fuel oil and lubricating oil. (wikipedia.org)

Indeed, ethylene oxide and propylene oxide are among the highest volume products in our industry, with annual production rates of 15 and 3 Mt per year, respectively. (rsc.org)
At the same time, due to the crystallinity and high linear structure of Fischer Tropsch wax, the physical and processing properties most suitable for PVC products can be obtained. (myerswax.com)

Organisms7

Chemicals and Drugs16

Health Care2

Hydrocarbons8

Cycloalkanes5

Aromatics3

Molecular10

Similar to those of alkanes1

Insoluble in water2

Alkenes and alkynes1

Liquid alkanes4

Atoms8

Carbon4

Concentrations6

Butane3

Selectivity4

Polyethylene2

Temperatures5

Mixtures1

Isomerism1

Cyclopentane2

Hydrogen2

Paraffin4

Methane4

Gasoline3

20201

Benzene1

Organic compounds1

Isomers2

Microbial1

Substitution1

Microorganisms2

Waxes1

Chemistry2

Isotopic1

Fuels3

Characteristic1

Occurs1

React1

Alcohols2

Ether4

Viscosity1

Density2

Fatty4

Formula1

Concentration2

Reaction2

Primarily1

Chemical3

Temperature4

Modification2

Atmosphere1

Catalysts2

Chem1

Form1

Products2