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141.
142.
The concentrations and chemical distributions of heavy metals (Cd, Cr, Ni, Zn, U, and V) in the Al-Jiza phosphate ores were investigated. Typically, the mean concentration values of Cd, Cr, Ni, U, and Zn are 15 ± 8, 109 ± 21, 34 ± 6, 211 ± 55, 142 ± 55, and 161 ± 57 mg kg?1, respectively. On the other hand, the encountered average concentration values of Cd, Cr, Ni, Zn, U, and V in the phosphate dust particles (<0.053) were found to be 22 ± 5, 179 ± 5, 67 ± 11, 441 ± 14, 225 ± 58, and 311 ± 9 mg kg?1, respectively. The contamination factors of U and Cr are greater than 1, indicating that these heavy metals could be potentially hazardous, if released to the environment. Multivariate statistical analysis allowed the identification of three main factors controlling the distribution of these heavy metals and the other chemical constituents. The extracted factors are as follows: francolite mineral factor, clay minerals factor, and diagenesis factor. Health risk assessments of non-cancerous effects in finer-grained size fraction that might be caused by contamination with the heavy elements have been calculated for both children and adults. The risk assessments in case of children for non-cancerous effects showed that U has values greater than the safe level of hazard index (HI = 1). In case of adults, the value of risk for U is also higher as compared to those of Cd, Ni, Cr, and Zn where it lies within the safe range of hazard index (HI < 1). Child health risk assessment indicates that children are more vulnerable to contaminants from phosphate mining than adults.  相似文献   
143.
This study was carried out to determine some bioclimatic characteristics such as humidity category (Q2), winter variant (m), the length of the dry season (LDS) and the dry season water deficit (DSWD) of naturally growing two endemic oak taxa, Quercus macranthera subsp. syspirensis and Q. petraea subsp. pinnatiloba, living in Turkey. Our findings showed that bioclimatic tolerance range of Q. macranthera subsp. syspirensis possess 7 different types of Mediterranean bioclimate while Q. petraea subsp. pinnatiloba had 8 of them. Although Q. macranthera subsp. syspirensis was ranging among the semiarid, freezing and very cold, Q. petraea subsp. pinnatiloba was among sub-humid, freezing and very cold ambient. It was briefly established that Q. macranthera subsp. syspirensis prefers semi-arid and very cold/freezing conditions and Q. petraea subsp. pinnatiloba prefers sub-humid and cold/very cold climatic conditions.  相似文献   
144.
Environmental Science and Pollution Research - The current study was conducted to assess the hematological and histopathological changes in major carp (Catla catla) exposed to different...  相似文献   
145.
Environmental Science and Pollution Research - Sentinel lymph node (SLN) sampling is important for evaluating the nodal stage of breast cancer when the axillary nodes are clinically free of...  相似文献   
146.

The exposure to bisphenols and their derivatives was assessed in 33 fish products sold in Turkey using high-performance liquid chromatography-tandem mass spectrometry (LC–MS/MS). BADGE was determined in only four samples at concentrations ranging between 0.06 and 0.22 mg/kg. As the most abundant bisphenol groups, BADGE-hydrolyzed products such as BADGE·H2O and BADGE·2H2O were present in nine and fourteen samples in the range between 0.06–0.16 and 0.06–0.72 mg/kg, respectively. The total concentration of BADGE and hydrolyzed products was below the specific migration limit (SML) value of 9 mg/kg food, which in the European Union stated as tolerable. Chlorinated derivatives of BADGE were detected in fewer samples compared with hydrolyzed ones. BADGE·H2O·HCl was the predominant migrant among chlorinated derivatives and was present in seven samples in a range between 0.02 and 0.06 mg/kg. All other samples contained less than or equal to 0.03 mg/kg of BADGE·HCl and BADGE·2HCl. The sum of these derivatives was lower than the SML value (1 mg/kg) of BADGE chlorohydrins legislated by the European Union. Besides these migrants, the analyzed samples did not contain any BFDGE and 3R-NOGE, which are prohibited in manufacturing food contact materials.

  相似文献   
147.
Environmental Science and Pollution Research - Macroinvertebrate community in the intertidal setup plays an important role in coastal ecosystem functions and biogeochemical cycle. However,...  相似文献   
148.
Municipal solid waste (MSW) is one of the most important environmental problems arising from rapid urbanization and industrialization. The use of alternative fuels in rotary kilns of cement plants is very important for reducing cost, saving fossil fuels and also eliminating waste materials, accumulated during production or after using these materials. Cement industries has an important potential for supplying preferable solutions to the waste management. Energy recovery from waste is also important for the reduction of CO2 emissions.This paper presents an investigation of the development of refuse derived fuel (RDF) materials from non-recycling wastes and the determination of its potential use as an alternative fuel in cement production in Istanbul, Turkey. RDF produced from MSW was analyzed and its effects on cement production process were examined. For this purpose, the produced RDF was mixed with the main fuel (LPG) in ratios of 0%, 5%, 10%, 15% and 20%. Then chemical and mineralogical analyses of the produced clinker were carried out. It is believed that successful results of this study will be a good example for municipalities and cement industries in order to achieve both economic and environmental benefits.  相似文献   
149.
Cu, Ni, Pb, Fe, Mn, Cr and Cd contents were determined in 17 different brands of chewing gum and candy samples available in local markets of Kayseri, Turkey. Concentration of selected trace metals were estimated using flame atomic absorption spectrometer after dry and wet digestion methods. Out of 17 brands of chewing gums and candies analysed, four were cocoa based, two were sugar based and other were of fruit based. Copper level ranged from 0.219 to 2.455 microg/g with an average of 1.390 microg/g. Nickel ranged from 0.120 to 2.588 microg/g with an average of 0.846 microg/g. Lead level ranged from 0.031 to 2.46 microg/g with an average of 0.746 microg/g. Iron level ranged from 3.963 to 9.863 microg/g with an average of 6.618 microg/g. Manganese level ranged from 1.872 to 5.067 microg/g with an average of 3.196 microg/g. Chromium ranged from 0.740 to 6.265 microg/g with an average of 2.473 microg/g and cadmium level ranged from 0.027 to 0.825 microg/g with an average of 0.296 microg/g. Cocoa based samples were found to have higher contents of the analysed metals than sugar and fruit based samples.  相似文献   
150.
Natural polymer, chitosan was obtained from dried prawn shell waste through the preparation of chitin and was characterized. Thin film of chitosan was prepared by casting method from its 2% chitosan solution. Mechanical properties like tensile strength (TS), elongation at break (Eb) of chitosan film were studied. Five formulations were developed with 2-ethyl-2-hydroxy methyl-1,3-propandiol trimethacrylate (EHMPTMA), a trifunctional monomer and 2-ethylhexyl acrylate (EHA), a monofunctional monomer in the presence of photoinitiator Darocur-1664 (2%). The film was soaked in those monomer formulations in dissimilar soaking times and irradiated under UV-radiation at different radiation intensities for the improvement of the properties of chitosan film. The cured films were then subjected to various characterization tests like TS, Eb, polymer loading (PL), water absorbency, gel content etc. The formulation, containing 25% EHMPTMA and 73% EHA showed the best performance at 10th UV passes of UV radiation for 4 min soaking time.  相似文献   
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