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41.
Environmental Science and Pollution Research - Green vegetation improvement is an economical strategy to mitigate dust air pollution. The anticipated performance index (API) is considered a main...  相似文献   
42.
Air overpressure (AOp) is one of the most adverse effects induced by blasting in the surface mines and civil projects. So, proper evaluation and estimation of the AOp is important for minimizing the environmental problems resulting from blasting. The main aim of this study is to estimate AOp produced by blasting operation in Miduk copper mine, Iran, developing two artificial intelligence models, i.e., genetic programming (GP) and gene expression programming (GEP). Then, the accuracy of the GP and GEP models has been compared to multiple linear regression (MLR) and three empirical models. For this purpose, 92 blasting events were investigated, and subsequently, the AOp values were carefully measured. Moreover, in each operation, the values of maximum charge per delay and distance from blast points, as two effective parameters on the AOp, were measured. After predicting by the predictive models, their performance prediction was checked in terms of variance account for (VAF), coefficient of determination (CoD), and root mean square error (RMSE). Finally, it was found that the GEP with VAF of 94.12%, CoD of 0.941, and RMSE of 0.06 is a more precise model than other predictive models for the AOp prediction in the Miduk copper mine, and it can be introduced as a new powerful tool for estimating the AOp resulting from blasting.  相似文献   
43.
The main purpose of this study was to ascertain whether occupational exposure to asphalt fumes, under normal working conditions, is associated with any hepatotoxic, nephrotoxic, or hematotoxic response. This was a cross-sectional study in which 210 subjects (80 exposed and 130 reference subjects) were investigated. Using standard methods, atmospheric concentrations of total particulate and benzene-soluble fractions of asphalt fumes were measured. Additionally, urine and blood samples were taken from subjects for complete blood count, white blood cell differential test, urinalysis, and routine biochemical tests of kidney and liver function. Both groups were similar as far as their demographic variables and smoking habits were concerned. The levels of exposure to total particulate and benzene-soluble fractions were estimated to be 0.9?±?0.2 and 0.32?±?0.09 mg m?3, respectively (mean?±?SD), both of which being lower than the existing threshold limit values. Statistically, significant associations between exposure to asphalt fumes and changes in most liver and kidney function tests and complete blood count parameters provided circumstantial evidence in favor of the notion that exposure to sub-threshold limit value levels of total particulate and benzene-soluble fractions is associated with early liver and kidney dysfunction as well as hematological disorders.  相似文献   
44.
This study investigates the effects of hydrogen enrichment on formation of pollutants and greenhouse gases in gas-fueled spark ignition engines. To this end, a previously validated detailed mechanism is embedded with a comprehensive one-dimensional engine model and the results are verified with experimental observations at different compression ratios and engine loads. The simulations are then performed for different mixtures of hydrogen and natural gas. The results indicate that adding hydrogen increases the cylinder peak pressure at different loads and compression ratios, despite the fact that reduces the amount of carbon monoxide, carbon dioxide, and methane in all the conditions.  相似文献   
45.
This study was performed to compare paper and sieving filtration methods for processing micro particles (< 20 μm) in roadway runoff for water quality evaluation. The consequence of a lack of reliable particle processing on particle number, particle concentration and particulate elemental composition, as well as their influence on particle mass and pollutant load calculations, is discussed. Results show that the paper filtering method can affect the measurement of particle size distributions of highway runoff samples. Contrary to common practice, it is not always correct to assume that the number and concentration of particles < 38 μm is the same as the number and concentration of particles < 20 μm. Processed samples for micro particles were most similar to unprocessed samples when nylon sieves were used. Samples filtered by paper deviated significantly from unprocessed samples. These deviations can cause inaccuracies up to 90 percent, in particle count and concentration, TSS calculations, elemental mass composition, and particle and elemental mass loading.  相似文献   
46.

This survey was performed to aim of synthesize Nano emulsion from Ferula gummosa essential oil (FEGO-NE) and to evaluate its anti-tumor effect. First, Ferula gummosa essential oil was analyzed by GC–MS method, and then the Nano emulsion was synthesized as O/W and after characterization by DLS, Zeta potential, AFM, FESEM and TEM methods, its toxicity was evaluated by MTT method. Then its pro-apoptotic effects were evaluated by qPCR (Caspase3, 9, Bax and Bcl-2) method and AO/PI staining. The cancer induction model was used to evaluate the antitumor effects in Balb/C mice. The anti-angiogenic and antioxidant effects were evaluated by qPCR (VEGF, CAT and SOD) method. The results of physicochemical studies showed the formation of droplet with dimensions of 24.6 nm, dispersion index of 0.41 and zeta potential of ? 28.5 mV with a spherical morphology. The Nano emulsion synthesized at a concentration of 2.9 μg/mL inhibited about 50% of ht-29 cells, while up to a concentration of 4 μg/mL showed no inhibitory effect on normal cells. Increase of caspase 3, 9 and Bax and decrease of BCL-2 gene expression along with increase of apoptotic cells in AP/PI staining confirmed induction of apoptosis by FEGO-NE. The FEGO-NE showed an inhibitory effect on angiogenesis and an additive effect on the expression of antioxidant genes. In addition, the reduction of tumor volume (69.72% in 14 days) in samples treated with FEGO-NE was confirmed. The results of this study showed that FEGO-NE by various mechanisms are able to inhibit cancer cells and have a reducing effect on induced tumors in the in vivo model. These results suggest FEGO-NEs as a suitable candidate for cancer therapy studies.

  相似文献   
47.
Environmental Science and Pollution Research - The significance of opportunistic infections in immunocompromised patients and the enigmatic pathogenicity of Blastocystis directed us to conduct the...  相似文献   
48.
Environmental Science and Pollution Research - In this work, copper hexaferrite (CuFe12O19) nanostructures are successfully synthesized by the sol-gel autocombustion route. Two natural reagents...  相似文献   
49.
Environmental Science and Pollution Research - Although several studies have investigated the long-term association of respirable particulate matter (PM?≤?10&nbsp;µm)...  相似文献   
50.
Heavy metals are increasingly being released into natural waters from geological and anthropogenic sources. The distribution of several heavy metals (Cr, Cu, Cd, Pb, Zn, and Hg) was investigated in muscle, gill, and liver in two different fish species seasonally collected in El-Mex Bay (autumn 2004-summer 2005). In order to evaluate the pollution status of the Bay, the concentrations of the selected metals in the labile and total fractions were analysed in sediment samples collected from eight sites in El-Mex Bay during autumn 2004. Also, the Index of Geoaccumulation (Igeo) for the sediment was estimated. The total and labile fractions of the selected metals in sediment samples were 15.2 and 62.8 μg g-1 dw for Cu, 1.8 and 5.0 μg g-1 dw for Cd, 79.1 and 130.3 μg g-1 dw for Zn, 0.2 and 1.2 μg g-1 dw for Hg, 35.8 and 93.0 μg g-1 dw for Pb, and 13.9 and 31.0 μg g-1 dw for Cr. The concentrations of all metals were lower in flesh than those recorded in liver and gill due to their physiological roles. The metal pollution index for fish was calculated. Health hazard calculations for the contaminated sediments and fish consumption were calculated to evaluate the effect of pollution on health.  相似文献   
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