Volatile oils studies

Selby, T. W. and Reichenbach, E. A., Engine Oil Volatility Studies - Generation of Phosphorus, Proceedings of the International Tribology Conference, Yokohama, Japan, 1995, pp. 813-816. 

Some of the more thorough studies of orange juice volatile composition were carried out by Schreier et al. [20], Duerr and Schobinger [21] and Nisperos-Carriedo and Shaw [22]. For example, Schreier et al. peeled the oranges before extraction in methanol to inactivate enzymes and prevent contamination from peel oil. Volatiles were separated from the aqueous juice using solvent extraction and were subsequently concentrated. Internal standards were employed to compensate for changes in concentration due to extraction/concentration or variation in sample introduction. Few subsequent studies prepared and analysed juice samples as thoroughly. 

Concentrated isolates from the two oat varieties were also studied. The volatile compounds were evaluated by smelling the GC effluent. Each oil was studied in triplicate. The peaks were described and the intensity of the perceived attributes was graded (scale 0-3). One trained person took part in this work. 

Fruits and juices have been investigated by a number of researchers. Schamp and Dirinck ( 5) found over forty compounds in a study of strawberry varieties, as well as finding 22 compounds in Golden Delicious apples. Keenaghan and Meyers ( ) reported on the GC/MS identification of over twenty different compounds in several varieties of apples and apple products. Additional work with apples has been reported by Westendorf ( 7) This same paper reported the analyses of dairy products, vegetable oils, and artificial flavors. Edible oils have been extensively studied since the presence of volatiles was first recognized as an indicator of oil quality (8). Considerable work with oils and oil-based foods using manual procedures has been reported by Jackson et al. (9,H)), Dupuy et al. (jU, 1 2), and Selke (1 3). In 1983 Roberts (F4) first reported the use of an automated DHA procedure for oil volatiles. 

We originally believed that the short chain saturated fatty acids In oxidizing fish lipids contributed to burnt/flshy flavors. Saturated fatty acid concentrations (C4 - Cg) measured by volatile headspace analysis (32, 59) reached levels as high as 3 ppm In highly oxidized fish oils (32). Flavor threshholds for these short n-chaln fatty acids In oil systems In the literature (>.66 ppm, 63) Indicate that they could contribute notes to oxidizing fish oils. However, studies designed to document the role of short chain acids as flavor compounds detracting from the flavor quality of fish oils did not confirm earlier beliefs. 

The molecular distribution and compound-specific carbon-isotopic composition of hydrocarbons can be used to qualify and quantify their sources and pathways in the environment. Molecular source apportionment borrows from molecular methods that were developed and applied extensively for fundamental oil biomarker studies, oil-oil and oil source rock correlation analysis. Additionally, petroleum refinement produces well-defined mass and volatility ranges that are used as indicators of specific petroleum product sources in the environment. Compound-specific carbon-isotopic measurement is a more recent addition to the arsenal of methods for hydrocarbon source apportionment. Carbon isotopic discrimination of i-alkanes, biomarkers, and PAHs has shown that the technique is highly complementary to molecular apportionment methods. 

Plant species belonging to the Amaryllidaceae family are widely distributed in several countries in the world. They are also cultivated as ornamental plants for their beautiful flowers and for the production of volatile oil. The study of Amaryllidaceae alkaloids began in 1877 with the isolation of lycorine [37, Fig. (9) and Table 2] from Narcissus pseudonarcissus [9], and the interest around this group of naturally occurring compounds has increased in time because of their effective antitumoral and antiviral activities. 

Analyses of phosphoms in the collected volatiles fi om the special Noack in these early studies [13-17] showed that phosphoms was present. Moreover, the limited data also suggested that phosphoms volatility was not closely related to oil volatility. 

A study of data published by the Institute of Materials (lOM) [18] for the years 1999 and 2000 of over 1200 oils was used. Phosphorus volatilized from fresh engine oils was ccm rared to 1) dieir oil volatilities and 2) initial phosphorus concentrations. Phosjdiorus volatility was first shown not to be dependent on engine oil volatility, as can be seen in Fig. 3 wdiere phosphoms volatility varies independently of the associated engine oil volatility. 

In an effort to determine the differences between engine oils having similar oil volatilities and fresh oil phosphorus concentrations, but markedly different phosphoms volatilities shown by the PEI, four oils were chosen from the lOM Engine Oil Database. Sufficient samples were received through the courtesy of lOM to run comparative special Noack tests, from which the volatile material and the residual oil for NMR studies were collected. These data, shown in Table 3 and Fig. 7, show the similarities of both oil volatilities and fresh oil phosphoms concentrations and are in clear contrast to the different levels of PEI, which are as great as 3700 %. 

In 2002, a paper was published on the phosphorus volatility results that appeared in the lOM database from 1999-2001 [9]. Contrary to expectations, it was found that phosphorus volatility was neither related to engine oil volatility nor to the phosphorus content in the unused engine oil. It was speculated that this lack of correlation with initial phosphorus additive concentration could be explained by either or both 1) effects of other engine oil additives and 2) variations in the chemistry of the phosphorus additives. A 2002 field study conducted by Ford Motor Company of catalyst degradahon by phosphorus-containing oils [10] was subsequently shown to correlate with the PEI data generated from the Selby-Noack bench test and, further, showed that phosphorus volatilization was strongly affected by other oil additives [11]. 

ABSTRACT Patchouli therapeutic effects were closely correlated with the non-volatile constituents except for patchouli oils. Few studies have been reported on the contents of non-volatile constituents, and it still remained unknown in the case what were the water-soluble components. The water-soluble components from roots, stems, leaves of P. cablin were isolated and identified by GC-MS in this paper. The result showed, a total of 25, 31 and 34 compounds were identified, accounting for 81.652%, 58.322% and 77.817% of water extracts from roots, stems and leaves, respectively. Six compounds (n-Pentadecanoic acid, [l,2 -Binaphthalene]-5,5, 8,8 -tetrone,T,4-dihydroxy-2,3 -dimethyl-, 1-Hexacosene, 1,2-Benzenediol, Docosane and Tricosane) were included in the water-soluble components from roots, stems and leaves. There were some differences in the water-soluble components from roots, stems and leaves of P. cablin. This might have been due the possibUity that the accumulation and storage of the water-soluble components was with relative independence. 

Apart from the separation of components of tobacco smoke, atmospherie pollutants, solvents, plant extracts, essential oils, volatile vegetable oils and organic acids etc., for which it is routinely used, gas chromatography is being increasingly used as an analytical tool to study... 

The PSMO test was utilized to study the used-oil volatility and deposit-forming tendencies. The volatility loss for the new oils at 225 C is shown in fig. 21.5. The volatile losses of the oils plateau at about 80%. This is partly due to the formation of deposits, which results in a reduction in the availability of liquid product. 

Essential is also used as the adjective form of the noun essence The mixtures of substances that make up the fragrant material of plants are called essential oils because they contain the essence that is the odor of the plant The study of the composition of essential oils ranks as one of the oldest areas of organic chemical research Very often the principal volatile component of an essential oil belongs to a class of chemical sub stances called the terpenes... 

Aerial parts of N. sintenisii yielded 0.3% of a clear yellowish oil. Forty constituents (96.5% of the total oil) were identified. The main components were 4aP,7a,7aP-nepetalactone (23.4%), elemol (16.1%), E- -farnesene (9.5%), 1,8-cineole (8.2%), cw-sabinene hydrate (6.5%), P-bisabolene (4.2%), germacrene-D (3.5%), P-sesquiphellandrene (2.8%), P-bourbonene (1.5%) and a-epi-cadinol (1.3%). According to available data, Nepeta species can be divided into two groups of nepetalactone-containing and nepetalactone-free species. The results of this study indicate that the compositions of volatile oil of N. sintenisii are similar to the other Nepeta genus and this plant could be classified in the group which 4aP,7a,7aP-nepetalactone is the major component of their oils. 

Thymus ciliatus Desf. is a wild growing plant spread in northeastern Algeria. Although the ehemieal eomposition of the volatile oils from several Thymus speeies is well studied, to our best knowledge no researeh has so far been eondueted on this Algerian thyme. 

Many applications involving the study of the composition of essential oils are based on the use of the on-column interface and retention gap techniques because of the high volatility of the components to be analysed. 

In studies on the moisture determination of corn by vacuum drying at 100° C., Sair and Fetzer (28) found that an error of about 0.5% in moisture content could be attributed to volatility of oils. The error was negligible in vacuum drying at 70° C. 

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