Aliphatic compounds contents

Using Py-GC/MS data and selecting the values of nine parameters for the pyrolysates (the content of long chain aliphatic compounds, content of benzene, toluene relative to total pyrolyzate, toluene relative to aromatic compounds, naphthalene relative to the content of benzene + naphthalene, cresol relative to aromatic compounds, cresols relative to toluene + cresols, and the level of o-cresol relative to total cresols), followed by the use of principal component analysis, it was possible to obtain the dendrogram shown in Figure 14.2.2. 

G. G. Jones and Miles [136] examined the ultra-violet absorption spectra of nitrocelluloses having a range of nitrogen contents from 10.9 to 14.1%. The absorption curve shows a maximum close to 220 ny, and an inflection below 300 my. The extinction is relatively small (e = 15.0). This is typical of aliphatic compounds which lack a conjugated double bond system and give only the R spectrum. 

Aliphatic acids content and total phenolic compounds did not change significantly with severity and were omitted from the table. 

The content of extractives and their composition vary greatly among different wood species and also within the different parts of the same tree (cf. Appendix). Wood extractives can be divided into three subgroups aliphatic compounds (mainly fats and waxes), terpenes and terpenoids, and phenolic compounds. Parenchyma resin is rich in aliphatic components and the oleoresin is mainly composed of terpenoids. Characteristic of the heartwood is the accumulation of phenolic compounds. 

Other Components of the Unsaponifiable Matter The unsaponifiable matter in a cmde regular sunflower oil is usually in the range of 0.5-1.5% (9, 17), or lower than 15 g/kg according to the Codex-Stan 210-1999. In addition to sterols (around 2.4. 6 g/kg) and tocopherols and tocotrienols (0.4-1.5 g/kg), there are minor components of sunflower oil. Aliphatic compounds and terpenoids occur naturally in oils. Of the terpenoid family, squalene is the most widely occurring compound. The occurrence of squalene in regular sunflower oil is fairly low 0.008-0.019% (5) or 15-20 mg/100 g (9). The aliphatic alcohol content is 100-mg/lOO-g oil (9). 

The content of phenols and volatile compounds (Ce aliphatic compounds) is correlated positively with fruit pigmentation up to a value after which a reverse tendency occurs. Maximal concentration was found when drupe pigmentation was not completed (semi-black), a time which... 

Citrus oils contain up to 95 % monoterpene hydrocarbons (usually (-t)-limonene, but others as well e.g., lemon oil also contains y-terpinene and /l-pinene). The important aroma-determining components of citrus oils are functionalized terpenes and aliphatic compounds (predominantly carbonyl compounds and esters), present only in relatively low concentrations [358, 358a]. Thus, several methods are employed to concentrate citrus oils on an industrial scale. The monoterpene hydrocarbon content is decreased by distillation, liquid-liquid partitioning between two immiscible solvents, or absorption on a carrier such as silica gel. The deterpenized concentrates are marketed under the name Citrus oil a-fold, depending on the concentration factor [358b]. 

Oil industry has a long history of application of NMR spectroscopy for characterization of crude oils, products and oil fractions. The methodology has been mainly ID proton- or carbon-detected experiments. Quantitative NMR and NMR experiments have been used in estimation of aromatic, olefin, naphtene and paraffin proportions in the samples. ° A more detailed characterization has been obtained using various ID carbon-detected experiments, like GASPE, CSE, QUAT and DEPT to obtain quantitative CH sub-spectra. " The goal of characterization of the oil fractions and quantification of certain structural features has been to find correlation between these features and the product properties (e.g. viscosity index, pour point). Due to environmental concerns oil companies are nowadays more interested in development of lubricant base oils that have low aromatic and olefin contents. Hydrogenation of unsaturated components also improves the stability of the base oils, which is an important property for the end-product. Quantitative analysis of a saturated oil fraction with NMR is a major challenge. When the oil fraction contains only aliphatic compounds, the spectrum width that contains the resonances narrows to ca. 1 ppm in the NMR spectrum and ca. 50 ppm in NMR spectrum. This causes excessive... 

The impact of pH correction to 5.5 on the chemical composition of the hydrolyzate has been studied before [29] and leads to a decrease of about 6% in monosaccharide content and a more considerable removal of fiiran derivatives and phenolic compounds (10-15%). Aliphatic acid contents are not significantly affected. 

Around 8% bromine content in the final PBT compound is sufficient to achieve the V-0 test rating for all types of brominated flame retardants, but some affect the physical and mechanical properties of the resultant materials more than others. Polymeric brominated styrene additives would be preferred in glass-filled compounds. Brominated polystyrene, such as Saytex HP-7010 from Albemarle Corp. and poly(dibromostyrene) are such materials. They retain excellent properties after heat ageing. High impact strengfti and excellent electrical properties are especially noted for HP-7010 due to the additive s high purity and low aliphatic halogen content. 

The C - NMR spectrum of this material (Figure 3) shows significant presence of substituted aromatic material (125 ppm) as well as aliphatic carbon content. This spectrum shows a considerably reduced presence of polysaccharide decomposition products compared to fulvic acid extracted from wastewater (11). The % -NMR spectrum (Figure 4) also indicates significant presence of substituted aromatic compounds (ca. 7 ppm). 

Early in the development of organic chemistry, organic compounds were arbitrarily classified as aliphatic or aromatic. Aliphatic compounds have open-chain structure. In addition to aliphatic compounds, there was a large number of compounds which were obtained from natural sources e.g., resins, balsams, aromatic oils etc., all of which had a pleasant odour. These compounds had higher percentage of carbon content than the corresponding aliphatic hydrocarbons and most of the simple compounds contained atleast six carbon atoms. These compounds were known as aromatic compounds. Further more, when these aromatic compounds were subjected to various methods of treatment, they often produced benzene or derivatives of benzene. 

Physical properties covered include purity, freezing point, vapour pressure, liquid density, vapour density, refractive index, rate of change of boiling point with pressure, latent heat of fusion, latent heat of evaporation, critical values, compressibility, viscosity, heat content, surface tension, and solubility. The 456 tables cover 434 aliphatic compounds and 22 miscellaneous compounds and elements. There is a cumulative index to the three volumes. Searching the Chemical Literature. 

Most solvent products, especially organic solvents and some additives, emitted from paints and varnishes are VOCs. The largest components of VOCs are solvents, e.g., aliphatic and aromatic hydrocarbons, alcohols, amines, acids, aldehydes, esters, ketones, ter-penes. The defrnition of the term VOC varies, a standard definition is published by CEN (European Committee for Standardization) VOCs are any organic liquids and/or sohds that evaporate spontaneously at the prevailing temperature and pressure of the atmosphere. VOCC (volatile organic compound content) is defined as follows Mass of the volatile organic compounds in a coating material, as determined under specified conditions. 

The composition of coal tar varies with the carbonization method but consists, largely, of mononuclear and polynuclear aromatic compounds and their derivatives. Coke oven tars are relatively low in aliphatic and phenolic content while low-temperature tars have much higher contents of both. 

Hydrocarbons, compounds of carbon and hydrogen, are stmcturally classified as aromatic and aliphatic the latter includes alkanes (paraffins), alkenes (olefins), alkynes (acetylenes), and cycloparaffins. An example of a low molecular weight paraffin is methane [74-82-8], of an olefin, ethylene [74-85-1], of a cycloparaffin, cyclopentane [287-92-3], and of an aromatic, benzene [71-43-2]. Cmde petroleum oils [8002-05-9], which span a range of molecular weights of these compounds, excluding the very reactive olefins, have been classified according to their content as paraffinic, cycloparaffinic (naphthenic), or aromatic. The hydrocarbon class of terpenes is not discussed here. Terpenes, such as turpentine [8006-64-2] are found widely distributed in plants, and consist of repeating isoprene [78-79-5] units (see Isoprene Terpenoids). 

A large amount of fuel and environmentally based analysis is focused on the determination of aliphatic and aromatic content. These types of species are often notoriously difficult to deconvolute by mass spectrometric means, and resolution at the isomeric level is almost only possible by using chromatographic methods. Similarly, the areas of organohalogen and flavours/fragrance analysis are dominated by a need to often quantify chiral compounds, which in the same way as aliphatic... 

Figure 2-77 shows how the weight distributions of the different molecular types vary during the fractional distillation of a naphthenic crude oil. Saturated aliphatic hydrocarbons (i.e., paraffins and naphthenes) are the predominant constituents in the light gasoline fraction. As the boiling point is raised, the paraffin content decreases, and the NSO content increases continuously. About 75 wt% of tbe residuum is composed of aromatics and NSO compounds. 

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