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To determine histograms of modified clinoptilolite in the study, 0.4-0.6 g. adsorbent sample, 0.5-2.0 mm fractions were selected. The regeneration process was carried out at a temperature t=250 ° C, also at the same time R=10 −5 mm.sim.ust. vacuuming to residual pressure was performed. During the experiments, the temperature was set at 25 ° C and the relative pressure of the adsorbent vapors was set at 0.4. Clinoptilolith water vapor, ethyl alcohol and benzene were slightly adsorbed. When the final rate of deinoalination of clinoptilolite was close to 40%, it reached its highest value at 3.5% for water vapor, 27% for ethyl alcohol, and 36% for benzene, i.e., the adsorption capacity of n samples was found to be increased. It was found that the degree of dealuminization of zeolite determines its adsorption properties. This was confirmed by the fact that the degree of dealuminization was the same in acid-treated samples under different conditions, but the magnitude of component adsorption was close. Experiments IR-spectroscopic studies were carried out on an IR-spectrometer "NicoleteIS-10" in the frequency range 400-5000 cm-1. Phase composition was performed using an X-ray analyzer 2DPHASER "Bruker" (CuK a - radiation, 2nd, 20-80 degrees). Electron microscopic images were taken under a Hitachi TM-3000 microscope. Elemental analysis was performed at Oxford Science. A vacuum scale with a Mac-Ben scale was used. The sorption volume W o of clinoptilolite decreased after acid treatment as the volume of adsorbed molecules increased: H2 O-Wo −0.13 cm3 / g, С2Н2ОН - Wo −0.107 cm 3 / g, C6 H6 −Wo −0.04 cm3 / g. 85% of the microporous volume in zeolite was spent on ethyl alcohol adsorption and 31% on benzene adsorption. The aim of the work is to study the adsorption properties of the sorbent obtained as a result of the process of acid modification of clinoptilotite from the Karmana deposit. [ABSTRACT FROM AUTHOR]

The present study was undertaken for qualitative tests for phytochemicals and evaluation of antifungal activity from stem of Shisham (Dalbergia sissoo Roxb.). The plant materials was collected from the university campus CCS, Haryana Agricultural University, Hisar. After this the plant materials were immediately brought to laboratory and were kept at room temperature under shade before processing. Result: It shows presence of various phytochemicals such as carbohydrates, sugars, saponins, proteins, flavanoids, triterpenoids and tannins etc. The maximum antifungal activity was found in chloroform fraction 98.23% growth inhibition at concentration 2000 μg/ml, moderate antifungal activity was shown by ethyl acetate and benzene fractions with 88.23% and 80.00% growth inhibition against tested fungi. Methanol fraction of D. sissoo stem showed 72.94% growth inhibition at 2000 μg/ml concentration followed by acetone and hexane fractions exhibited by 70.58% growth inhibition at 2000 μg/ml against Rhizoctoniasolani fungi. [ABSTRACT FROM AUTHOR]

Benzene, toluene, ethylbenzene, p-xylene, O3, NOx, CO, PM2.5 and meteorological parameters were measured in urban air of one site in Tijuana, Baja California, Mexico during winter 2016-2017. Samples were collected using 1.5 h time intervals at four different sampling periods ( B1: 07:30-09:00 h, B2: 12:00-13:30 h, B3: 15:00-16:30 h, B4: 18:00-19:30 h) before being analyzed by gas chromatography with flame ionization detection. The highest concentrations of BTEX occurred during the morning (B1) and afternoon (B4) sampling periods. Mean concentrations of BTEX were 32.40 µg/m³ for benzene; 13.28 µg/m³ for toluene; 17.16 µg/m³ for p-xylene; and 7.02 μg/m3 for ethylbenzene. The toluene/benzene, xylene/ethylbenzene concentration ratios and meteorological analysis indicated that BTEX levels were influenced by local and fresh emissions (vehicular traffic). Bivariate (Pearson correlation) and multivariate analyses (Principal Component Analysis) were performed in order to correlate BTEX concentrations with criteria air pollutants and meteorological parameters to infer their possible sources. These results suggest that changes in the existing environmental policies should therefore be applied to improve air quality. [ABSTRACT FROM AUTHOR]

The popularity of wet wipes application continues to grow, because they are an important part of skin care for millions of people around the world. Wet wipes may consist of lots of substances that can cause irritation of skin or allergy and subsequently, their composition is necessary to be identified. The aim of this study was to perform screening organic compounds in wet wipes by solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry. Screening was carried out by analysis of six samples of wet wipes. Alcohols, esters, ketones, aldehydes, acids, aromatic compounds and terpenes were identified in the samples. Among identified alcohols, methanol and phenoxyethanol that can cause allergy was identified. Propylene glycol that can be referred to a group of preservatives was found out in 2 samples. Derivatives of benzene as ethyl benzene, methylethyl benzene and butyl ethyl benzene were also observed almost in all samples. Diethyl phthalate that is not prohibited to use in hygiene products was observed in one wet wipe sample. Applied parameters of solidphase microextraction and gas chromatography-mass spectrometry can be used in future for development of quantitative methodology for particular compounds as phthalates, alkoxyalcohols, aromatic hydrocarbons and preservatives. [ABSTRACT FROM AUTHOR]

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Structural evolution of vapor-deposited ethylbenzene (EB) and isopropylbenzene (IPB) were studied by in situ wide-angle X-ray (WAX) diffraction as the temperature was raised stepwise. The as-deposited glasses of both compounds showed a broad hump in the diffraction pattern indicating their amorphousness. Low-density glasses deposited at temperatures much lower than the glass transition temperature (Tg), the hump contained a low-angle component. It diminished accompanying the structural relaxation preceding the glass transition. These results are in harmony with our previous observations that such glasses showed shrinkage in advance of the glass transition. As examples of high-density glasses deposited at temperatures close to Tg, EB glass deposited at 105 K and IPB glass deposited at 121 K were studied. At the glass transition, the former EB glass showed an unexpected stepwise shift of the hump to the high-angle direction, while the latter IPB glass showed almost no change in the diffraction pattern. These observations are briefly discussed referring to our recent results obtained other experimental methods. [ABSTRACT FROM AUTHOR]

Thermal properties of vapor-deposited ethylbenzene glasses were studied by raising the temperature with a constant rate. We improved the sensitivity of the thermal sensor and data-accumulation method of the measurement used in our previous study [Chem. Lett., 39, 77 (2010)]. Thus an unexpected endothermic peak was observed in the relaxation process accompanying the volume shrinkage before the glass transition for the glass deposited at 80 K. This suggests that the glass deposited at the temperature much lower than the glass transition temperature (Tg) has a significantly inhomogeneous structure. For the glass deposited at 105 K, a sharp endothermic peak was observed accompanying a steep volume expansion before the glass transition. This supports our previous inference that the dense glasses deposited at temperatures close to Tg include a large amount of locally stable molecular conformations and they diminish in the structural relaxation preceding the glass transition. [ABSTRACT FROM AUTHOR]

On the example of the synthesis of ethylbenzene, an approach to reaction network formalization was proposed. This approach consists in grouping the components according to their reactivity their reactivity with respect to a specific reaction. The values of compensation degrees of reactions as an indicator of components reactivity were calculated. The kinetic model of alkylation of benzene with ethylene and heavy alkylates transalkylation was developed. The proposed approach is promising for development of mathematical modeling of multi-component processes of oil refining and petrochemical industries. [ABSTRACT FROM PUBLISHER]