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991.
992.
Konstantinos C. Makris Dibyendu Sarkar Jason Salazar Pravin Punamiya Rupali Datta 《Environmental science and pollution research international》2010,17(1):195-202
Background, aim, and scope
Alum (aluminum sulfate) is the currently preferred chemical amendment for phosphorus (P) treatment in poultry litter (PL). Aluminum-based drinking-water treatment residuals (Al-WTRs) are the waste by-product of the drinking-water treatment process and have been effectively used to remove P from aqueous solutions, but their effectiveness in PL water extracts has not been studied in detail. Elevated cost associated with alum could be minimized by using the equally effective WTRs to remove soluble P from PL, and they can be obtained at a minimal cost from drinking-water treatment plants. 相似文献993.
Sarah A. Styler 《环境科学学报(英文版)》2015,27(4):132-134
<正>In their recent Journal of Environmental Sciences publication,Wang and colleagues provide field evidence that industrial activities can contribute substantially to atmospheric carbonyl concentrations(Wang et al.,2015).These results may helpto explain underestimations of carbonyl emissions in currently available emission inventories,and highlight the need for an improved understanding of industrial sources of this class of compounds.In the atmosphere,carbonyl compounds photolyze to yield 相似文献
994.
F. Olcay Topac Sagban 《环境科学学报(英文版)》2011,23(4):616-623
The possible impacts on nitrogen-cycle in a p-nitrophenol (PNP) polluted soil and the e ectiveness of wastewater sludge amendments
in restoring nitrification potential and urease activity were evaluated by an incubation study. The results indicated that PNP at 250 mg/kg
soil inhibited urease activity, nitrification potential, arginine ammonification rate and heterotrophic bacteria counts to some extents.
After exposure to PNP, the nitrification potential of the tested soil was dramatically reduced to zero over a period of 30 days. Based
on the findings, nitrification potential was postulated as a simple biochemical indicator for PNP pollution in soils. Nitrogen-cycling
processes in soils responded positively to the applications of wastewater sludges. A sludge application rate of 200 tons/ha was su cient
for successful biostimulation of these nitrogen processes. The microbial activities in sludge-amended, heavy PNP-polluted soils seemed
to recover after 30–45 days, indicating the e ectiveness of sludge as a useful soil amendment. 相似文献
995.
996.
钼磷酸氧化萜烯醇光度法测定矿山废水中松脂油(二号油) 总被引:1,自引:0,他引:1
在文献的基础上,利用钼磷酸在浓硫酸作用下于乙醇介质中优先氧化萜烯酸及其衍生物,而本身被还原为钼兰的性质,本文建立了测定矿山废水中松脂油的方法,方法检出限为0.006mg/5ml,回收率在88%—107%之间,相对标准偏差为5.05%。本文还对钼磷酸的溶剂选择,钼磷酸和浓硫酸的用量对吸光度的影响,以及浓盐酸的用量对萃取效率影响做了详细研究。 相似文献
997.
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
998.
Analysis of trace dicyandiamide in stream water using solid phase extraction and liquid chromatography UV spectrometry 总被引:1,自引:0,他引:1
An improved method for trace level quantification of dicyandiamide in stream water has been developed. This method includes sample pretreatment using solid phase extraction. The extraction procedure (including loading, washing, and eluting) used a flow rate of 1.0 mL/min, and dicyandiamide was eluted with 20 mL of a methanol/acetonitrile mixture (V/V = 2:3), followed by pre-concentration using nitrogen evaporation and analysis with high performance liquid chromatography–ultraviolet spectroscopy (HPLC–UV). Sample extraction was carried out using a Waters Sep-Pak AC-2 Cartridge (with activated carbon). Separation was achieved on a ZIC®-Hydrophilic Interaction Liquid Chromatography (ZIC-HILIC) (50 mm × 2.1 mm, 3.5 μm) chromatography column and quantification was accomplished based on UV absorbance. A reliable linear relationship was obtained for the calibration curve using standard solutions (R2 > 0.999). Recoveries for dicyandiamide ranged from 84.6% to 96.8%, and the relative standard deviations (RSDs, n = 3) were below 6.1% with a detection limit of 5.0 ng/mL for stream water samples. 相似文献
999.
本文从珠江三角洲地区酸雨监测数据资料入手,对本地区酸雨状况及其趋势进行探讨,研究结果表明,本地区酸雨依然严重,且广泛存在。 相似文献
1000.
Novel 3D biogenic C-doped Bi_2 MoO_6/In_2O_3-ZnO Z-scheme heterojunctions were synthesized for the first time, using cotton fiber as template. The as-prepared samples showed excellent adsorption and photodegradation performance toward the hazardous antibiotic doxycycline under simulated sunlight irradiation. The morphology, phase composition and in situ carbon doping could be precisely controlled by adjusting processing parameters. The carbon doping in Bi_2 MoO_6/In_2O_3-ZnO was derived from the cotton template, and the carbon content could be varied in the range 0.9–4.4 wt.% via controlling the heat treatment temperature. The sample with Bi_2 MoO_6/In_2O_3-ZnO molar ratio of 1:2 and carbon content of1.1 wt.% exhibited the highest photocatalytic activity toward doxycycline degradation,which was 3.6 and 4.3 times higher than those of pure Bi_2 MoO_6 and Zn In Al-CLDH(calcined layered double hydroxides), respectively. It is believed that the Z-scheme heterojunction with C-doping, the 3D hierarchically micro–meso–macro porous structure, as well as the high adsorption capacity, contributed significantly to the enhanced photocatalytic activity. 相似文献