Analysis of Occupational Hazard Factors and Control Measures at a Shoe Factory

Shoe factory workers are exposed to many kinds of occupational hazard factors, including organic solvents, dust and noise. In order to prevent and control occupational diseases and protect the health of workers, the situation of occupational harmful factors in production site of shoe factory was investigated. The concentrations of toxic substances in air were measured. The results showed that benzene, toluene, ethylene dichloride and noise exceeded the standards by 13.0%, 8.7%, 26.1% and 8.7%, respectively. The effect of occupational hazards management and control is poor, and the qualified rate of monitoring in workplaces is low. The employers should strengthen the management and control of benzene series, dust and noise in the workplace to reduce the health hazards to workers.

Evaluating volatile organic compounds from Chinese traditional handmade paper by SPME-GC/MS

Once printed, books are always accompanied by the smells of volatile organic compounds (VOCs) which are continuously emitted not only by inks but also by papers themselves throughout their lives. Although the VOCs from papers may bring mild discomfort to readers, they are considered as very important factors that feature the degradation of papers and show potential applications in cultural relic appraisal. In this study, an analytical approach based on solid phase microextraction combined with gas chromatography-mass spectrometry (SPME-GC/MS) was proposed for the evaluation of volatile organic compounds (VOCs) emitted by Chinese traditional handmade papers. The VOCs evaluations and artificial aging processes were both applied to recent-made papers and naturally aged papers from a traditional Chinese calligraphy and painting scroll (collected by the National Museum of China). To be noticed, a large number of aliphatic acids, aldehydes, ketones, furan derivatives, benzene series and terpenoid substances indicated that the VOCs signals not only reveal the degradation of paper but also tentatively reflect the storage environment along hundreds of years ago. The semi-quantitative evaluation of markers indicated that the historical paper is under a serious degradation due to the high capacity it releases. Our results provided a path way to get the degradation information of ancient paintings as well as potential realistic applications such as the conservation of paper-based relics and the environmental protection in libraries and museums.

Synthesis and antiprotozoal activity of 2-phenoxy derivatives of pyridine

The aim of the present work is to synthesize phenoxypyridine derivatives and to screen substances with a high level of biological activity within the series of synthesized compounds, which is essential for solving the problem of overcoming the growing drug resistance of bacteria and protozoa. The interaction of 2-chloro-5-nitro- and 2-chloro-3-nitro-pyridine with aromatic aldehydes containing phenolic hydroxyl gave 15 pyridine series aryl ethers in high yields when reacted in dimethylformamide (DMFA) or dimethyl sulfoxide (DMSO) in the presence of bases. In the reaction we used phenolic derivative of kojic acid (compound 1 of Table 1), a number of benzene series aldehydes with different substituents: 3-methoxy-4-hydroxybenzaldehyde (compound 2 of Table 1), 4-hydroxybenzaldehyde (compound 3 of Table 1), 2,4-dihydroxybenzaldehyde (compound 5 of Table 1), 3-methoxy-4-hydroxybenzaldehyde (compound 7 of Table 1 ), salicylic aldehyde (compound 11 of Table 1), 3,4-dihydroxybenzaldehyde (compound 12 of Table 1), vanillin (compound 13 of Table 1), and compound 15 (Table 1) of the benzene series with two hydroxyl and aldehyde groups. As well as benzene-type aldehydes, the methyl ester of salicylic acid (compound 4 of Table 1), 4-hydroxymethylphenol (compound 6 of Table 1), 4-acetylphenol (compound 8 of Table 1), and 3-hydroxy benzoic acid (compound 14 of Table 1) were used. In the reaction, in addition to the above compounds, 7-hydroxycoumarin (compound 9 of Table 1) and semicarbazide-4-hydroxybenzaldehyde (compound 10 of Table 1) were also used. Their purification was performed by recrystallization from organic solvents (ethyl acetate, benzene, ethanol, and isopropanol). The obtained compounds were studied as part of the institute's search for compounds to expand the range of active substances with protistoсid and antibacterial activity with low toxicity. Synthesized compounds have pronounced antiprotozoal activity against Colpoda steinii. the most active compound contains a nitro group in the 3rd position of the pyridine ring as well as an aldehyde and hydroxyl group in the benzene ring. The minimum protistocidal concentration of this compound is 0.9 µg/ml, which is 60 fold more active than toltrazuril and 8 fold more active than chloroquine. This compound is recommended for extended toxicological and pharmacological studies.

Release characteristics of Pb and BETX from in situ oil shale transformation on groundwater environment

Oil shale has received attention as an alternative energy source to petroleum because of its abundant reserves. Exploitation of oil shale can be divided into two types: ex situ and in situ exploitation. In situ transformation has been favoured because of its various advantages. Heating of oil shale leads to the production of oil and gas. To explore the influence of solid residue after pyrolysis of oil shale on the groundwater environment, we performed ultrapure water–rock interaction experiments. The results showed that Pb tended to accumulate in solid residues during pyrolysis. Additionally, the Pb concentration goes up in the immersion solution over time and as the pyrolysis temperature increased. In contrast, when we measured the soaking data of benzene series, the concentrations of benzene and toluene produced at temperatures over 350 ℃ were highest in the four oil shale pyrolysis samples after pyrolysis. The water–rock interaction experiment for 30 days led to benzene and toluene concentrations that were 104 and 1070-fold over the limit of China’s standards for groundwater quality. Over time, the content of benzene series was attenuated via biological actions. The results show that in situ oil shale mining can lead to continuous pollution in the groundwater environment.

Gas-Phase Advanced Oxidation (GPAO) for Gas Containing Benzene Series by Ultraviolet Irradiation/Hydrogen Peroxide Vapour (UV/[H2O2]g) Process

Hydrogen peroxide (H2O2) has the remarkable characteristics of strong oxidation, in which its vapour ([H2O2]g)has further advantages, such as economize and good light transmission. But there is very rare research about its degradation effect in Gas-Phase Advanced Oxidation (GPAO). In the present study, the photochemical oxidation for gas containing benzene series, using ultraviolet (UV) irradiation and [H2O2]g, was investigated in a transparent bag made of fluorinated ethylene propylene (FEP). Only UV or [H2O2]g hardly reduced the pollutant in 5 hours in which the reactor was also stable. With the high pollutant concentration (248 to 756 mg/m3) and short residence time (3S) compared with the related studies, studying the degradation of benzene, toluene and xylene, the apparent rate by UV/[H2O2]g/(powder active carbon, PAC) was higher compared with the different way (UV/[H2O2]g, UV/[H2O2]g/TiO2 and UV/[H2O2]g/ZnO), but it was found that the terminal degradation by UV/[H2O2]g significantly decreased, in which the conductivity decreased after reaction. The effects of increasing pollutant concentration and H2O2 pH were negative for the treament, but the UV radiated power positive till 40W. In addition, the characteristic absorbance for three benzene series showed that the key structure of pollutant molecule were damaged in GPAO.