Acetone, degradation product

A monitoring system has been established to determine 90 pesticides including anilides and 10 related degradation products in river water. Pesticide residues in the water sample are collected on a PS-2 cartridge (265-mg) at a flow rate of 10 mL min, eluted with 3 mL of acetone, 3 mL of n-hexane and 3 mL of ethyl acetate successively, and determined by GC/MS. Overall recoveries ranged from 72 to 118%. Recoveries of mepronil, naproanilide, propanil and flutolanil at fortification levels of 0.1 and 2 mg kg Mn water by this method were 80-112%. The LODs were 0.01 -0.1 pg L ... 

Acetone was detected in diesel fuel at a concentration of 22,000 pg/g (Schauer et al., 1999). Identified as an oxidative degradation product in the headspace of a used engine oil (10-30W) after 4,080 miles (Levermore et al., 2001). Acetone also was detected in automobile exhaust at concentrations ranging from 0.09 to 4.50 mg/m (Grimaldi et al, 1996) and in cigarette smoke at concentrations ranging from 498 to 869 mg/m (Euler et al., 1996). 

Fluorescamine reacts instantaneously with the primary amino groups of peptides, yielding a fluorescent product with an excitation peak at 390 nm and an emission band at 475 nm. It is insoluble in water and is usually prepared in acetone. Neither the reagent nor the degradation products of the excess reagent in an aqueous medium are fluorescent, which is a great advantage, particularly when postcolumn derivatization is used. 

Formation of Benzal- Acetone Structures. Formation of a peroxy group at C-5 (oxidation of structure lid) leads to ring opening between C-4 and C-5 and to formation of benzal acetone structures, which are assumed to be the possible source of the obtained degradation products (acetone and acid V, respectively, w-propyl methyl ketone and acid VI). 

In order to gain some information on the degradation mechanisms, experiments with substances assumed to represent essential intermediates were undertaken. 2-Hydroxy-3-methoxy-5-methylbenzal acetone (XVII) is considered to play a dominant role in the proposed degradation mechanism when 6,6 -bicreosol is oxidized in alkaline solution although it could not be detected among the degradation products. The benzal acetone (XVII) was oxidized and underwent alkaline hydrolysis under our standard conditions. Alkaline hydrolysis in nitrogen atmosphere yielded rather small amounts of acetone (about 10% of theoretical amount). Oxidation yielded... 

Isolation and Quantitative Determination of Degradation Products of 6,6 Bicreosol (II). The reaction mixture was filtered to remove unreacted 6,6 -bicreosol, which precipitated during oxidation because of the decreasing pH of the solution. Further amounts of unreacted starting material could be isolated by continuously extracting the bicarbonate alkaline filtrate with ether after determining acetone. 

Terbuthylazine and degradation products Hot acetone, then cation exchange solid-phase cartridge High-performance liquid chromatograph with photodiode array detection [74,75]... 

Table 1 (48a,b) shows the 24 hr results of the test described above on phenylbutazone. Copper degraded phenylbutazone both as a salt and as acetyl acetonate. Iron was less aggressive, and the free salt was stronger than the complex. The degradation products were 4-hydroxy- and 4-hydroperoxy-phenylbutazone, the known oxidation impurities. The susceptibility of phenylbutazone to metal oxidation can be attributed to activation of the hydrogen on C-4 by the adjacent carbonyls. Selegiline hydrochloride, a stable compound, was not oxidized under the same conditions. This confirms the discriminating power of the experimental conditions. 

Alcohol is distilled up to a content of 96% in one or more stages. About 1 % of ethanol consists of fusel oils (degradation products of amino acids) which can be used as solvents for lacquers and resins. Solids from the processed liquor containing proteins, carbohydrates, mineral salts, riboflavin and other vitamins are used in poultry, swine and cattle feeds. C02 and H2 produced in butanol-acetone-butyric acid production can be used for the chemical synthesis of methanol and ammonia, or are burned. 

In the traditional "wood distillation industry" hardwood was preferred for production of chemicals. Hardwood distillation was formerly an important source for production of acetic acid, methanol, and acetone which were the primary products of this process. The heat required for pyrolysis was generated by burning gas, oil, or coal. In the thermal degradation of wood the volatile components are distillable and can be recovered as liquids after condensation (Fig. 10-2). The solid residue, charcoal, is mainly composed of carbon. At higher temperatures the carbon content is increased because of a more complete dehydration and removal of volatile degradation products. Charcoal is mainly used as combustible material for special purposes. A number of charcoal products are known, including activated carbon for adsorption purposes. 

In principle, the same carbohydrates and their degradation products formed after hydrolysis of wood can be recovered from sulfite spent liquors. However, this requires complicated and expensive separation techniques. The industrial use of sulfite spent liquor components is mainly limited to fermentation processes. The most common product is ethyl alcohol which is produced from hexose sugars by yeast (Saccharomyces cerevisae) and separated from the mixture by distillation. Even the carbon dioxide formed in the process can be recovered. Other fermentation products, including acetone, n-butanol, and lactic acid, can be produced by certain microorganisms. Because some contaminants, for example, sulfur dioxide, inhibit the growth of the yeast, they must be removed from the liquor prior to the fermentation. 

The radiation degradation of poly(2-octyne) occurs only in the presence of oxygen. Its degradation products contain carbonyl and hydroxyl groups, and so dissolve in polar solvents (e.g., acetone). Such solubility change is essential to resist materials. The Gs value (number of main-chain scission per 100 eV of absorbed dose) of poly(2-octyne) is ca. 12. It is noteworthy that this value is higher than that of poly-(methyl methacrylate) (Gs ca. 2)118) which is being used as electron-beam resists. 

For the purpose of analyzing ezetimibe in combination with simvastatin, three HPTLC methods have been developed. The first method was developed by Shivshankar et al. [33] and yielded higher Rf values for either ezetimibe or simvastatin. In the method developed by Dhaneshwar et al. [30], a combination of toluene and isopropanol was shown to produce shorter Rf times for ezetimibe and simvastatin, leading to methods of shorter duration and lower mobile phase consumption. The recent method developed by Dixit et al. [31] used combination of acetone and n-hexane as the mobile phase and resulted in shorter Rf values when compared to the other two methods for assessing ezetimibe in combination with simvastatin. This method has also been validated to distinguish the degradation products of ezetimibe. Further, during the determination of ezetimibe in combination with atorvastatin, shorter Rf values were obtained as well as better peak shape when a combination of toluene and methanol was used as the mobile phase [30]. 

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