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Examination of Forensic Evidence
Published in Karen D. Sam, Thomas P. Wampler, Analytical Pyrolysis Handbook, 2021
John M. Challinor, David A. DeTata, Kari M. Pitts, Céline Burnier
Volatilization of the lipstick using the Py-GC process indicates the presence of cetyl acetate (CA) and isopropyl myristate (IPM). Heptanal (C-7AL), a pyrolysis product of castor oil, is a major product. The THM profile in this case is more complex and gives more information about the composition of the product. Cetyl acetate is converted to the methyl ether of cetyl alcohol (C-16-OME), while IPM is partly converted to the methyl ester. The major components, RIC-OME and RIC, are identified as the methyl ether of ricinoleic acid methyl ester and ricinoleic acid methyl ester having a free OH group, respectively. These compounds result from hydrolysis and complete—or partial—methylation of the major component of castor oil. The presence of coconut oil in the formulation is confirmed by the detection of the C8.0 and C10.0 fatty acid methyl esters. This product was differentiated from more than 60 lipsticks examined in the study, based on the composition of the organic components.
Thermochemistry, Electrochemistry, and Solution Chemistry
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
4-Fluorobenzoic acid Fluoroethane Fluoromethane Fluoromethane Fluoromethane 1-Fluoropropane 2-Fluoropropane 5-Fluorouracil Folic acid Folic acid Folpet - -Fructose Furan 2-Furancarboxylic acid 2-Furancarboxylic acid Furfural Galactaric acid -Galactose -Glucitol - -Glucose - -Glucose - -Glucose -Glutamic acid -Glutamic acid -Glutamic acid -Glutamic acid -Glutamine Glycerol triacetate Glycine Glycine Glycine Glycolic acid Glycolic acid N-Glycylglycine Glyphosate Guanidinoacetic acid Guanine Guanosine Haloperidol Heptachlor 2,2',3,3',4,4',6-Heptachlorobiphenyl Heptadecanoic acid 1,6-Heptadiyne Heptanal Heptane Heptane Heptane Heptane Heptanedioic acid Heptanedioic acid Heptanoic acid 1-Heptanol 1-Heptanol 1-Heptanol 1-Heptanol 2-Heptanol, ()3-Heptanol, (S)4-Heptanol 2-Heptanone 2-Heptanone
Physical Properties of Individual Groundwater Chemicals
Published in John H. Montgomery, Thomas Roy Crompton, Environmental Chemicals Desk Reference, 2017
John H. Montgomery, Thomas Roy Crompton
Biological. Heptane may biodegrade in two ways. The first is the formation of heptyl hydroperoxide, which decomposes to 1-heptanol followed by oxidation to heptanoic acid. The other pathway involves dehydrogenation to 1-heptene, which may react with water, forming 1-heptanol (Dugan, 1972). Microorganisms can oxidize alkanes under aerobic conditions (Singer and Finnerty, 1984). The most common degradative pathway involves the oxidation of the terminal methyl group, forming the corresponding alcohol (1-heptanol). The alcohol may undergo a series of dehydrogenation steps, forming heptanal, followed by oxidation, forming heptanoic acid.
New 1,2-dithioether based 2D copper(I) coordination polymer: from synthesis to catalytic application in A3-coupling reaction
Published in Journal of Coordination Chemistry, 2019
Sankar Saha, Kinkar Biswas, Pranab Ghosh, Basudeb Basu
In order to explore the generality of the optimized reaction conditions, different types of substrates such as secondary amines with different types of aldehydes were allowed to react with terminal acetylenes. Very good to excellent isolated yields of the products have been achieved under this protocol (Table 5). In Table 5, it is clearly evident that various aldehydes including electron releasing or withdrawing groups such as OMe, OH, Br, Cl as well as benzaldehyde reacted smoothly with terminal alkynes (phenyl acetylene and 4-bromophenyl acetylene) and cyclic secondary amines (morpholine, piperidine and pyrrolidine). Furthermore, the reaction of an alicyclic aldehyde (cyclohexanecarboxaldehyde) and straight-chain aliphatic aldehyde (n-heptanal) with morpholine and phenylacetylene were performed efficiently and afforded the desired products in brilliant yields (entries 9 and 10).
Impact of different FD-related drying methods on selected quality attributes and volatile compounds of rose flavored yogurt melts
Published in Drying Technology, 2021
Kay Khaing Hnin, Min Zhang, Bin Wang
The volatile components of fresh samples were compared with those found in three different dried rose flavored yogurt melts (Table 2). There were 87, 75, and 65 components identified in total for FD, IRPSFD, and MPSFD samples, respectively. It was shown that ketones (accounting for 7.7, 7.22, and 7.64%) and esters (accounting for 12.4, 11.23, and 9.23%) and acids (accounting for 0.77, 1.17, and 0.55%) of FD, IRPSFD, and MPSFD samples were the main classes of compounds of dried rose flavored yogurt melts compared to fresh samples. There is a difference between the kinds and quantity of volatile components in fresh and dried rose flavored yogurt melts. Overall, the amounts of alcohols, aldehydes, and other volatile compounds apparently reduced after drying. Conversely, the amounts of ketones, esters, and acids evidently increased after drying. This is perhaps because the drying encouraged the esterification reaction of alcohols, diminishing the content of alcohols and growing the content of esters.[30] Some alcohols (e.g., 1-pentanol; 1-pentanol, 4-methyl-; 10-undecen-1-ol; 6-octen-1-ol, 3,7-dimethyl-, (R)-; 2,6-octadien-1-ol, 3,7-dimethyl-, formate, (E)-; geraniol; phenylethyl alcohol; and 2-hexadcanol); aldehydes (e.g., heptanal; octanal; 2-heptenal, (Z); nonanal; 2,6-octadienal, 3,7-dimethyl-, (E)-; and 2-propenal, 3-phenyl-) and other compounds decompose when exposed to heat. Meanwhile, some ketones (e.g., 2-heptanone, 6-methyl-; 5-hepten-2-one, 6-methyl-; and 2-undecanone), esters (e.g., acetic acid, hexyl ester, and acetic acid, 2-phenylethyl ester) and acids (e.g., octanoic acid) provide the dried sample more flavor is produced during drying.
Inhalation exposure to volatile organic compounds in the printing industry
Published in Journal of the Air & Waste Management Association, 2019
Abdullah Alabdulhadi, Ashraf Ramadan, Peter Devey, May Boggess, Maya Guest
The following 14 VOCs were likely used in all three printeries: 1,3,5-TMB, 1,2,3-TMB, m/p-xylene, toluene, o-DCB, benzyl chloride, acetone, heptanal and octanal, methyl and ethyl alcohol, bromoform, vinyl chloride and CFC-114 (ordered from highest concentration to lowest). Of these, the last five may have been sourced in part from the outdoors. The newspaper printery had the highest concentration of 1,3,5-TMB found in this study: 225 ppb in offset. They also had 1,2,3-TMB at 50 ppb in CTP and 1,2,4-TMB at 15 ppb in CTP and offset. The scientific printery had lowest total aromatics, but considerable concentrations of TMBs: 170 ppb of 1,3,5-TMB, 50 ppb of 1,2,4-TMB and 35 ppb 1,2,3-TMB in the offset area. In the government printery, the most prevalent aromatics were 1,3,5-TMB and 1,2,4-TMB, both 130 ppb, in offset and 1,2,3-TMB at 50 ppb also in offset. Three printery air quality studies in the US between 1995 and 2007 found considerable amounts of 1,3,5-TMB and 1,2,4-TMB (Batterman et al. 2002; Rodriguez and Gibbins 2007; Wadden et al. 1995). In fact, the study of Batterman et al. (2002) found that one of the solvents used had 1,2,4-TMB as a major ingredient, and that it accounted for 66% of the total VOCs in that printery; 1,3,5-TMB accounted for 15% of total VOCs. In a review of stated ingredients in printery products, Sutton, Wolf, and Quint (2009) found that 1,2,4-TMB was commonly used in blanket wash. On the other hand, documented use of 1,2,3-TMB was sparse. In comparison to previous reports then, the study printeries were using more 1,2,3-TMB than expected. There is reason to take note of increased TMB usage in printeries since animal studies have demonstrated neurotoxic effects all three TMB isomers (Gardner 2012; Korsak and Rydzynski 1996; Wiaderna, Gralewicz, and Tomas 2002).