Past,present, and future use of phosphorus in Chinese agriculture and its influence on phosphorus losses

Large inputs of phosphorus (P) in chemical fertilizers and feed supplements since 1978 have improved soil P status in arable land in China, but have also created challenges by increasing P concentrations in manure and exacerbating water quality degradation. Arable land in China can be divided into five management zones based on soil P chemistry, with 15–92 % of arable land having lower P status than the agronomic optimum and 0.3–7.2 % having severe risks of P leaching losses. A scenario analysis of soil P budget and agronomic P demand during 2011–2030 highlighted the great pressure China faces in sustainable P management and the need for drastic changes in current practices. This includes new policies to reduce P supplementation of feed and improved P use efficiency by livestock and programs to expand the adoption of appropriate fertilization, soil conservation, and drainage management practices to minimize P losses.     

电弧流溶胞技术促进污泥厌氧消化

为提高污水厂处理污泥时的厌氧消化速率,利用电弧流溶胞技术处理剩余污泥,研究电弧流溶胞技术对污泥破解预处理效果的影响.实验结果表明,与未经预处理的污泥相比,电弧流溶胞处理能够明显提高污泥厌氧消化效率,增加有机物含量和沼气产量.其中,经处理后的污泥TS、VS剩余量分别降低了8.3%和6.3%,COD增加了11.9%.厌氧系统平均产气量平均增加79.76 L/d,增加率45.82%,甲烷含量增加1.03 L/d,增加率102%.由此说明,电弧流溶胞技术可以提高厌氧消化反应中有机物的去除率,有效促进厌氧消化中污泥的水解过程,显著增加甲烷气体的产生量.在综合考虑运行费用和污泥消化效果的前提下,采取适宜的电弧流强化处理措施有一定的积极意义.     

In situ hydrothermal fabrication of visible light-driven g-C3N4/SrTiO3 composite for photocatalytic degradation of TC

Environmental Science and Pollution Research - A series of g-C3N4/SrTiO3 (CN/SrTiO3) composites with the different mass ratio of g-C3N4 were prepared by facile in situ hydrothermal growth method,...     

2008年黑龙江省环境状况及发展趋势分析

黑龙江省生态环境状况良好,野生动植物栖息和生长的环境逐步改善。主要污染物化学需氧量和二氧化硫排放量继续呈下降趋势。城市空气质量良好,处于全国中上游水平,城市噪声污染较轻。松花江水质稳中趋好,为轻度污染,部分支流水质明显改善,出境水质达标的频率大幅增加。     

聚乙烯醇/氧化石墨插层纳米复合材料的结构和热分析

制备了聚乙烯醇/氧化石墨插层纳米复合材料,并用X-射线衍射仪和高分辨电镜对其结构进行了表征.X-射线衍射仪和高分辨电镜的试验结果表明,氧化石墨和聚乙烯醇插层氧化石墨的层间距分别为0.89 nm和1.4nm.该纳米复合材料的热分析和热失重图说明,氧化石墨的加入有利于提高聚乙烯醇/氧化石墨纳米复合材料的玻璃化转变温度和氧化温度,同时也降低了其热释放速率.     

六个行业熔铅作业防毒工程技术措施综合评价(第一部分)

在对印刷、铁路车辆、电缆压铅、铅蓄电池、铅盐、铅冶炼这六个行业的熔铅作业以及对铅蓄电池和铅盐生产的铅尘作业中防毒工程技术措施调研的基础上,介绍了它们的基本情况。参照收集的国内外资料,采用定性及定量化的方法,对它们的防毒工程技术措施分别从工艺设备、排风罩类型、净化装置等得出优化选择结论,对还存在的问题进行讨论并提出建议。     

Simultaneous treatment of PVC and oyster-shell wastes by mechanochemical means

This work presents a new process for dechlorinating poly-vinyl chloride (PVC) by the use of oyster-shell waste. The process consists of milling of PVC waste with oyster-shell waste, followed by washing the milled sample with water. The milling of PVC and oyster-shell mixture results in size reduction and rupture in bonds, leading to mechanically induced reactions between the two to form CaCl2 and hydrocarbon with C=C bonds. Washing the milled mixtures with water at room temperature allows complete removal of chlorine from the milled sample. More than 95% of chlorine in PVC was removed when 2h grinding is conducted for the mixture. The present process could offer a potential route to the handling and disposal of oyster-shell and PVC wastes.