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31.
Organic matters (OMs) and their oxidization products often influence the fate and transport of heavy metals in the subsurface aqueous systems through interaction with the mineral surfaces. This study investigates the ethanol (EtOH)-mediated As(III) adsorption onto Zn-loaded pinecone (PC) biochar through batch experiments conducted under Box–Behnken design. The effect of EtOH on As(III) adsorption mechanism was quantitatively elucidated by fitting the experimental data using artificial neural network and quadratic modeling approaches. The quadratic model could describe the limiting nature of EtOH and pH on As(III) adsorption, whereas neural network revealed the stronger influence of EtOH (64.5%) followed by pH (20.75%) and As(III) concentration (14.75%) on the adsorption phenomena. Besides, the interaction among process variables indicated that EtOH enhances As(III) adsorption over a pH range of 2 to 7, possibly due to facilitation of ligand–metal(Zn) binding complexation mechanism. Eventually, hybrid response surface model–genetic algorithm (RSM–GA) approach predicted a better optimal solution than RSM, i.e., the adsorptive removal of As(III) (10.47 μg/g) is facilitated at 30.22 mg C/L of EtOH with initial As(III) concentration of 196.77 μg/L at pH 5.8. The implication of this investigation might help in understanding the application of biochar for removal of various As(III) species in the presence of OM.  相似文献   
32.
A novel photocatalyst based on TiO_2–PANI composite supported on small pieces of cork has been reported. It was prepared by simple impregnation method of the polyaniline(PANI)–modified TiO_2 on cork. The TiO_2–PANI/Cork catalyst shows the unique feature of floating on the water surface. The as-synthesized catalyst was characterized by X-ray diffraction(XRD),scanning electron micrograph(SEM), transmission electron microscopy(TEM), thermogravimetric analysis(TGA), Fourier transform infrared spectroscopy(FT-IR), UV–vis diffuse reflectance spectra(UV–vis DRS) and the Brunauer–Emmett–Teller(BET) surface area analysis. Characterization suggested the formation of anatase highly dispersed on the cork surface. The prepared floating photocatalyst showed high efficiency for the degradation of methyl orange dye and other organic pollutants under solar irradiation and constrained conditions, i.e., no-stirring and no-oxygenation. The TiO_2–PANI/Cork floating photocatalyst can be reused for at least four consecutive times without significant decrease of the degradation efficiency.  相似文献   
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34.
Bacterial diversity of full scale rotary drum composter from biodegradable organic waste samples were analyzed through two different approaches, i.e., Culture dependent and independent techniques. Culture-dependent enumerations for indigenous population of bacterial isolates mainly total heterotrophic bacteria (Bacillus species, Pseudomonas species and Enterobacter species), Fecal Coliforms, Fecal Streptococci, Escherichia coli, Salmonella species and Shigella species showed reduction during the composting period. On the other hand, Culture-independent method using PCR amplification of specific 16S rRNA sequences identified the presence of Acinetobacter species, Actinobacteria species, Bacillus species, Clostridium species, Hydrogenophaga species, Butyrivibrio species, Pedobacter species, Empedobactor species and Flavobacterium species by sequences clustering in the phylogenetic tree. Furthermore, correlating physico-chemical analysis of samples with bacterial diversity revealed the bacterial communities have undergone changes, possibly linked to the variations in temperature and availability of new metabolic substrates while decomposing organics at different stages of composting.  相似文献   
35.
Increasing levels of Heracleum persicum (golpar) in drinking water were studied in broilers. Two hundred and forty-one-day-old male chickens were allocated to one of six treatments: control, without added phytogenics nor probiotics in drinking water, and probiotics at recommended manufacturer’s level (P) or 1.0, 1.5, 2.0, and 2.5 ml/l of golpar extract solution (G1, G1.5, G2, and G2.5 treatments, respectively) in drinking water. As a result of this study, no linear or quadratic trends in the feed intake (FI) and feed conversion rate (FCR) due to golpar supplementation were found. Body weight gain, final body weight, and relative carcass weight showed a positive linear response with increasing levels of golpar supplementation. Neither golpar nor probiotics had effects on the percentages of edible parts of the carcass. Golpar supplementation levels caused a linear negative response of the albumin content in blood plasma, whereas both abdominal fat as percentage of carcass weight and uric acid levels in blood plasma linearly increased. The effects on Ig responses were only observed at 42 days of age and were similar in probiotics and the highest level of golpar supplementation. Based on our results, both probiotics and golpar supplementation could improve broiler performance and immune function.  相似文献   
36.
The mechanical behavior of municipal solid waste (MSW) has attracted the attention of many researchers in the field of geo-environmental engineering in recent years and several aspects of waste mechanical response under loading have been elucidated. However, the mechanical response of MSW materials under undrained conditions has not been described in detail to date. The knowledge of this aspect of the MSW mechanical response is very important in cases involving MSW with high water contents, seismic ground motion and in regions where landfills are built with poor operation conditions. This paper presents the results obtained from 26 large triaxial tests performed both in drained and undrained conditions. The results were analyzed taking into account the waste particles compressibility and the deformation anisotropy of the waste samples. The waste particles compressibility was used to modify the Terzaghi effective stress equation, using the Skempton (1961) proposition. It is shown that the use of the modified effective stress equation led to much more compatible shear strength values when comparing Consolidated-Drained (CD) and Consolidated-Undrained (CU), results, explaining the high shear strength values obtained in CU triaxial tests, even when the pore pressure is almost equal to the confining stress.  相似文献   
37.
Sunflower plants were treated with 14C-chlorpyrifos under conditions simulating local agricultural practice. Residues present in the oil, methanol extract and cake of the treated sunflower seeds were 7.2, 2.8, and 12 ppm, respectively. When rats fed on sunflower cake containing bound residues for three days, the animals eliminated 46 % of the radioactivity in urine, 25 % in feces and 10 % in the expired air. A further bioavailable amount of 8 % was found in selected organs indicating that the bound residues were highly bioavailable. Chromatographic analysis of urine extract revealed the presence of the parent compound, its oxon, desethyl chlorpyrifos and desethyl chlorpyrifos oxon as free metabolites in addition to a conjugated metabolite. It was liberated by acid hydrolysis and identified as 3,5,6-trichloro-2-hydroxypyridine. Bound residues were found to have biological effects such as inhibition of rat plasma ChE, elevations of liver parameters (ALT, AST, and ALP), decrease in total protein and albumin content suggesting a hepatotoxic potential. A significant increase in the values of creatinine, urea, cholesterol, triglycerides and significant decrease in Catalase and Glutathion-S-Transfrase were observed in treated rats.  相似文献   
38.
The primary objective of this study was to identify gaps in coastal and marine data available through the Gulf Geospatial Assessment of Marine Ecosystems (GAME) project for the west coast of Florida. A survey was designed and sent to more than 2,000 experts working with coastal and ocean issues in the Gulf of Mexico to elicit their opinions. The survey asked the experts to rank 12 data categories and score the relevance of four qualifiers (spatial resolution, temporal resolution, age of data, and level of detail) using a discrete choice approach. The statistical interpretation of experts?? responses allowed assigning a relative value to each available data set, based upon their qualifiers. The results were then displayed in a Geographic Information System to visually show how the total value for all data categories or for a specific data category varies spatially and to identify data gaps. It was found that the total data set value is generally higher within Tampa Bay and along the coast. Areas with low total value show a lack of data sets that have qualifiers falling within the ideal range, as per experts?? opinions. The gap maps created for this project are useful to identify priority areas where money should be invested for future data collection.  相似文献   
39.
Selection of landfill site is a complex process and needs many diverse criteria. The purpose of this paper is to evaluate the suitability of the studied site as landfill for MSW in Karaj. Using weighted linear combination (WLC) method and spatial cluster analysis (SCA), suitable sites for allocation of landfill for a 20-year period were identified. For analyzing spatial auto-correlation of the land suitability map layer (LSML), Maron’s I was used. Finally, using the analytical hierarchy process (AHP), the most preferred alternative for the landfill siting was identified. Main advantages of AHP are: relative ease of handling multiple criteria, easy to understand and effective handling of both qualitative and quantitative data.As a result, 6% of the study area is suitable for landfill siting and third alternative was identified as the most preferred for siting MSW landfill by AHP.The ranking of alternatives were obtained only by applying the WLC approach showed different results from the AHP. The WLC should be used only for the identification of alternatives and the AHP is used for prioritization. We suggest the employed procedure for other similar regions.  相似文献   
40.
Environmental Science and Pollution Research - Drug resistance of cancer cells is a major issue in cancer treatment. Plant-mediated nanoparticle synthesis has been applied in recent years to...  相似文献   
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