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Abstract

Pollution negative influences the environmental, human health, buildings and increase the production of waste. We are currently witnessing pollution and degradation in some cases irreversible, of the environment. Environmental issues are extremely complex and cover all sectors. Worldwide, industrial pollution strategies necessary to reduce emissions to the atmosphere hydrocarbons, volatile organic compounds (VOCs) and other polluants in urban areas. The highest concentrations of volatile organic compounds of more than 80 mg/m3 occur in densely populated areas. The latest data reported in the residential area of Cluj-Napoca values did not exceed 20 m /m3. However peaks reported VOC concentrations, depending on the season, exceeding the upper limit that according to Law. 104/2011 is 75 μ/m3. It was identified due to increase annual mean concentration of VOCs as, in particular, road traffic exceeding sanitary standards on the main traffic routes within the city. In this paper the results obtained after carrying out an analysis of the average VOC concentration recorded in the city Cluj-Napoca as a result of car traffic. They were pursued average concentrations of VOCs resulting from the combustion of liquid fuels, petrol and diesel type. Analyzing the results obtained are proposed solutions for reducing VOC emissions. The rule under which these solutions have been proposed to reduce the concentration of VOCs took into account the possibility implementation and maintenance costs thereof.

Abstract

ZnO-CuO flower-like hetero-nanostructures were successfully prepared by combining hydrothermal and dip coating methods. Flower-like hetero-nanostructures of ZnO-CuO were examined by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and UV-Vis. The sensing properties of ZnO-CuO flower-like hetero-nanostructures to volatile organic compounds (VOCs) were evaluated in a chamber containing acetone or isopropanol gas at room temperature. The sensitivity of ZnO-CuO flower-like hetero-nanostructures to VOCs was enhanced compared to that of pure leafage-like ZnO nanostructures. Response and recovery times were about 5 s and 6 s to 50 ppm acetone, and 10 s and 8 s to 50 ppm isopropanol, respectively. The sensing performance of ZnO-CuO flower-like hetero-nanostructures was attributed to the addition of CuO that led to formation of p-n junctions at the interface between the CuO and ZnO. In addition, the sensing mechanism was briefly discussed.

References [1] Kostiainen, R. (1995). Volatile organic compounds in the indoor air of normal and sick houses. Atmos. Environ ., 29(6), 693-702. DOI: 10.1016/1352-2310(94)00309-9. [2] Katsoyiannis, A., Anda, E.E., Cincinelli, A., Martellini, T., Leva, P., Goetsch, A., Sandanger, T.M. & Huber, S. (2014). Indoor air characterization of various microenvironments in the Arctic. The case of TromsØ, Norway. Environ. Res. 134, 1-7. DOI: 10.1016/j.envres.2014.06.011. [3] Uchiyama, S., Tomizawa, T., Tokoro, A., Aoki, M., Hishiki, M., Yamada, T., Tanaka, R., Sakamoto, H

Protection Engineering, 39, 139-152. DOI: Margeta, K., Zabukovec Logarn, N., Šiljeg, M., & Farkas, A. (2013). Natural Zeolites in Water Treatment - How Effective is Their Use. Water Treatment, Dr. Walid Elshorbagy (Ed.), InTech, DOI: 10.5772/50738. Mathur, A. K., Majumder, C. B., & Chatterjee, S. (2007). Combined removal of BTEX in air stream by using mixture of sugar cane bagasse, compost and GAC as biofilter media. Journal of Hazardous Materials, 148, 64-74. DOI: 10.1016/j.jhazmat.2007.02.030. Meininghaus, C. K. W., & Prins, R. (2000). Sorption of volatile organic

References Kostrzewski P, Piotrowski JK. Toluene determination in capillary blood as a biological indicator of exposure to low levels of toluene. Pol J Occup Med Environ Health 1991;4:249-59. Janasik B, Jakubowski M, Jalowiecki P. Excretion of unchanged volatile organic compounds (toluene, ethylbenzene, xylene and mesitylene) in urine as a result of experimental human volunteer study. Int Arch Occup Environ Health 2008;81:443-9. Imbriani M, Ghittori S. Gases and organic solvents in urine as biomarkers of occupational exposure: a review. Int Arch Occup

detection of melanoma. Appl. Anim. Behav. Sci., 89, 2004, 107-116. PRADO, C., MARTIN, P., PERIAGO, J.F.: Application of solid phase microextraction and gas chromatography-mass spectrometry to the determination of volatile organic compounds in end-exhaled breath samples. J. Chromatogr. A, 1011, 2003, 125-134. SPANEL, P., ROLFE, P., RAJAN, B., SMITH, D.: The selected ion flow tube (SIFT)-a novel technique for biological monitoring. Ann. Occup. Hyg., 40, 1996, 615-626. WARNEKE, C., KUCZYNSKI, J., HANSEL, A., JORDAN, A., VOGEL, W., LINDINGER, W.: Proton transfer reaction mass

modifiers for the next generation of environmentally friendly coatings. Paint & Coatings Industry. 2012;28(3):20-26. [16] Chen SP, Liu WT, Ou-Yang CF, Chang JS, Wang JL. Optimizing the emission inventory of volatile organic compounds (VOCs) based on network observations. Atmospheric Environ. 2014;84:1-8. DOI: 10.1016/2013.10.059. [17] Faber J, Brodzik K, Gołda-Kopek A, Łomankiewicz D. Air pollution in new vehicles as a result of VOC emissions from interior materials. Polish J Environ Stud. 2013;22(6):1701-1709. [18] Zabiegała B. Organic compounds in indoor environments

References [1] Janicka, A., Ocena toksyczności mikroatmosfery środowiska wnętrza pojazdu samochodowego , Wydawnictwo Politechniki Wrocławskiej, Wroclaw 2014. [2] Heidi, H., Sources and concentrations of volatile organic compounds in urban air , 2006. [3] Bin, X., Xiaokai, C., Xiong, J., Air quality inside motor vehicles’ cabins , A review, 2016. [4] Danish Environmental Protection Agency, Risk assessment of hazardous substances in the indoor environment of cars – a pilot study , 2017. [5] Górniak, A., Janicka, A., Król, A., Lis, J., Włostowski, R. M

Precursors of volatile organic compounds emitted during phosphorite processing

The composition of solvent-soluble organic matter of phosphorite, which is a precursor of volatile organic compounds emitted by the fertilizer industry, was studied. A benzene-methanol mixture and chloroform were used for the extraction of free and bound bitumen from phosphorites, respectively. The separated bitumen fractions were characterized qualitatively by GC-MS and quantitatively by GC-FID. n-Alkanes, n-alkenes, fatty acids and isoprenoids were identified in the extracts. The main components were n-alkanes and n-alkenes, constituting over 80% of the total bitumen determined. An unexpected presence of n-alkenes only in the free bitumen fraction was found. The possible source of ill-smelling substances evolved during treatment of phosphorite with H2SO4 was discussed.

Abstract

Hybrid Rugosa is the most winter hardy group of roses in the climatic conditions of the Baltic Sea region. This study aimed at identifying new qualities of Hybrid Rugosa by focusing on determination of content of volatile organic compounds of flower petals and in hydrosols produced from these. Volatiles of seven cultivars were extracted using solid phase microextraction (SPME) with subsequent separation by gas chromatography. Identification was made by comparison with mass spectral libraries and by calculating linear retention indexes and comparing them with literature data. Twenty-five volatile aroma compounds were identified in the petals and hydrosols of six Hybrid Rugosa and species. Among those, phenylethylalcohol, ß-citronellol, geraniol and nerol were predominant. Species Rosa rugosa and variety ‘Plena’ showed the highest total level of volatiles and contained 26% and 31% ß-citronellol, respectively. Varieties ‘Raita’ and ‘Sniedze’ contained up to 57% citronellol. The main volatile compounds were detected in hydrosols in the same proportions, but their concentration was higher than in petals. The varieties ‘Raita’ and ‘Violeta’, bred in Latvia, are recommendable for use as a source of hydrosol.