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991.
A glasshouse pot experiment was conducted to investigate Cd concentrations in the aboveground parts of two consecutive crops of rice and Cd availability in three different soils (loam, silt loam, and sandy loam) after application of pig manure with added Cd. Soil pH tended to increase with increasing application rate of pig manure from 1 to 3% (w/w, oven dry basis). Soil diethylene triamine pentaacetic acid (DTPA) extractable Cd showed a clear positive correlation with soil total Cd content and increased with increasing Cd amendment of the manure but showed no difference between the two manure application rates. Cd concentrations in the grain, husk, and straw were significantly and positively correlated with soil DTPA-extractable Cd (p < 0.001). Within each level of manure Cd, the higher rate (3%) of manure produced lower Cd concentrations in the grain, husk, and straw on all three soils than did the lower rate (1%) after the first crop, but this no longer occurred after the growth of the second crop. Grain Cd concentrations exceeded the Chinese National Food Quality Standard (0.2 mg kg(-1)) most often on the loam, with intermediate frequency on the silt loam, and least often on the sandy loam, the soil with the highest pH and lowest organic carbon content and cation exchange capacity.  相似文献   
992.
采用NaBH4作为还原剂回收电镀废液中的铜。正交实验结果表明,各因素对剩余铜离子质量浓度的影响的显著性顺序为n(NaBH4)∶n(CuSO4)反应时间反应温度。最佳实验条件为:n(NaBH4)∶n(CuSO4)=1.50,反应温度30℃,反应时间25min。经该工艺可获得平均粒径为33nm的近球形立方晶系纳米铜粉,处理后废液中铜离子质量浓度低至0.2mg/L。在铜粉制备过程中加入非离子型表面活性剂可有效阻止晶粒长大,并提高其分散性能,使产物粒径均匀。采用苯骈三氮唑处理后的铜粉抗氧化能力明显提高。  相似文献   
993.
Environmental Science and Pollution Research - Continuously improving freshwater aquaculture efficiency will promote the sustainable development of freshwater aquaculture, which is crucial to...  相似文献   
994.
Environmental Science and Pollution Research - As the major energy consumers, energy-intensive industries are the key players in achieving carbon emission reduction targets. The paper builds a...  相似文献   
995.
Environmental Science and Pollution Research - Many parts of the vehicle cabin generate volatile organic compounds (VOCs), and some are hazardous and/or odorous to humans. In this study, VOCs in...  相似文献   
996.
Environmental Science and Pollution Research - Under the background that China puts forth the goals of “Emission Peak” and “Carbon Neutrality”, heavily polluting...  相似文献   
997.
Xu  Peiwei  He  Xiaoqing  He  Shengliang  Luo  Jinbin  Chen  Qiang  Wang  Zuoyi  Wang  Aihong  Lu  Beibei  Wu  Lizhi  Chen  Yuan  Xu  Dandan  Chen  Weizhong  Chen  Zhijian  Wang  Xiaofeng  Lou  Xiaoming 《Environmental science and pollution research international》2021,28(6):6691-6699
Environmental Science and Pollution Research - To better understand the cardiopulmonary alterations associated with personal exposed PM2.5-bound heavy meals, we conducted a cross-sectional study in...  相似文献   
998.

The content of fine sand (< 200 μm) in primary sludge is relatively high in Chongqing sewage treatment plant owing to the part of rainwater will be mixed with sand and discharged into the municipal pipe network. Due to the insufficient separation of the sand, different obstacles to subsequent treatment processes may increase equipment wear, reduce effective volume of the tank, or shorten the cleaning cycle. There is a common use of grit chamber for the separation. Nevertheless, the use of hydrocyclone shows an outstanding performance in cost effectiveness and ease operation. The primary sludge in a sewage plant in Chongqing was monitored, and the average concentration of total suspend solids (TSS), total sand content, and volatile suspended solid (VSS) were 40.25 g/L, 17.51 g/L, and 13.41 g/L, respectively. The size of sand in the sludge was small, and the sand below 30 μm accounted for about 70% of the total sand. It formed flocs with organic matter and was removed in subsequent process units. While the size between 30–200 μm, called fine sand, was the main separation object, accounted for about 28.5%. According to XRF and XRD analysis, the sludge composition was mainly composed of quartz (SiO2), plagioclase (Na(AlSi3O8)), and calcite (CaCO3), which were similar to the main mineral composition of surface sediments and mountain rocks in the main urban area of Chongqing. A single-factor experiment on two types (FX100 and FX50) of hydrocylones was conducted to determine their abilities concerning the separation of fine sand and enrichment of organic matters from primary sludge. FX100 and FX50 showed best performance in the case of P = 0.17 Mpa, underflow diameter (Du) = 18 mm and P = 0.20 Mpa, Du = 6 mm, respectively. The removal efficiency of fine sand by hydrocyclone FX50 was 71.39%. While, it had poor performance on organic matter enrichment and the removal efficiency of which was 17.38%. By contrast, the removal rate by FX100 reached 61.89% for fine sand and only 6.89% for organic matters detached. The superimposition effect did not appear in the serial experiments on hydrocylone FX100 and FX50, but the power is 3.5 times of that of single-stage hydrocylone FX100. Comprehensive consideration of the processing capacity per unit time and operating power, the hydrocylone FX100 was more suitable for actual operation.

  相似文献   
999.
Environmental Science and Pollution Research - The new severe acute respiratory syndrome coronavirus 2 was initially discovered at the end of 2019 in Wuhan City in China and has caused one of the...  相似文献   
1000.
Environmental Science and Pollution Research - This paper examines urban environmental performance using a unique database of 286 Chinese cities for the period 2002–2014. Both the dynamics of...  相似文献   
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