基于灰关联分析的时间序列改变点搜索研究——以华东地区农业受灾面积序列为例

采用灰关联分析方法,构建了短时间序列中的改变点搜索算法,有效地解决了短时间序列改变点寻找的缺陷.首次将灰关联度算法应用到气象灾害时间序列改变点的搜索中,利用华东地区农业受灾面积时间序列实例来验证灰关联度算法的实用性和有效性.结果表明,用灰关联方法可以有效地获得改变点,并以此对时间序列的发展规律进行趋势与规律分析.     

Responses of CH(4), CO(2) and N(2)O fluxes to increasing nitrogen deposition in alpine grassland of the Tianshan Mountains

To assess the effects of nitrogen (N) deposition on greenhouse gas (GHG) fluxes in alpine grassland of the Tianshan Mountains in central Asia, CH₄, CO₂ and N₂O fluxes were measured from June 2010 to May 2011. Nitrogen deposition tended to significantly increase CH₄ uptake, CO₂ and N₂O emissions at sites receiving N addition compared with those at site without N addition during the growing season, but no significant differences were found for all sites outside the growing season. Air temperature, soil temperature and water content were the important factors that influence CO₂ and N₂O emissions at year-round scale, indicating that increased temperature and precipitation in the future will exert greater impacts on CO₂ and N₂O emissions in the alpine grassland. In addition, plant coverage in July was also positively correlated with CO₂ and N₂O emissions under elevated N deposition rates. The present study will deepen our understanding of N deposition impacts on GHG balance in the alpine grassland ecosystem, and help us assess the global N effects, parameterize Earth System models and inform decision makers.     

Titanium dioxide nanoparticles relieve biochemical dysfunctions of fifth-instar larvae of silkworms following exposure to phoxim insecticide

Phoxim insecticide is widely used in agriculture, which is toxic to insect pests and nontarget organisms. The phoxim poisoning is hard to prevent for silkworms. TiO₂ NPs have been widely applied in whitening, brightening foods, toothpaste or sunscreens, and orally-administered drugs. However, whether TiO₂ NPs can increase resistance of silkworm to phoxim poisoning has not been reported. The results demonstrated that added TiO₂ NPs significantly decreased reduction of protein, glucose and pyruvate contents, lactate dehydrogenase, succinate dehydrogenase and malate dehydrogenase activities, and attenuated increases of free amino acids, urea, uric acid and lactate levels, activities of protease, alanine aminotransferase and aspartate aminotransferase in the hemolymph of silkworms caused by phoxim exposure. From the present study, it is clearly evident that added TiO₂ NPs may relieve toxic impacts of phoxim insecticide on silkworm metabolism, which in turn may result in an increase in silk yield.     

水解/AMBBR/好氧工艺和传统A/O工艺处理低碳源污水的对比研究

为提高低碳氮比污水中易生物降解有机物的含量,实验设计了水解(H)/移动床生物膜反应器(AMBBR)/好氧(O)工艺,并与传统A/O工艺对比,考察其作为低碳源污水脱氮工艺的可行性。通过小试对比低温下(10.9~13℃)两工艺中污泥的反硝化性能,并进行了实验室规模的中试运行。小试结果显示,AMBBR两相污泥对硝酸盐的去除率比单纯反硝化污泥高出19.4%。中试结果表明,相同的运行条件下,两工艺对COD和NH3-N的去除效率相当,但H/AMBBR/O工艺对总氮的去除效率均优于传统A/O工艺;在各自最优工况下,前者平均总氮去除率较后者高出22.39%,且前者通过剩余污泥的回流水解实现了部分污泥减量化,尤其是对于温暖地区,该工艺能够有效改善低碳源污水脱氮性能。     

企业安全操作规程编制探讨

编制安全操作规程是企业安全管理的重要工作,针对企业编制安全操作规程时存在的问题,总结企业编制安全操作规程的经验,从内容、资料收集、编制流程等环节提出改进和完善的方向,促进提高企业安全管理水平。     

不同温度下有机负荷对厌氧折流板反应器污泥颗粒化的影响

采用2个相同的厌氧折流板反应器（ABR）研究不同温度、有机负荷对ABR启动过程中胞外聚合物（EPS）产生的影响,以及各隔室优势菌种。结果表明,高温和较高的有机负荷（OLR）促进EPS的产生,而EPS有利于颗粒污泥的形成。较高温度也有利于反应器承受更高的有机负荷。启动结束后,沿着水流方向,隔室中的污泥发生变化,由水解酸化菌演替为产甲烷优势菌。     

络合铁法脱除垃圾填埋气中的H2S

建立了以EDTA和柠檬酸为铁盐络合剂的循环脱硫体系,采用络合铁法对垃圾填埋气中的H₂S进行脱硫中试实验,结果表明实验所建立的络合铁脱硫体系运行稳定,脱硫效率高,适合应用于垃圾填埋气中硫化氢脱除。     

直接红染料的臭氧脱色与中间产物研究

以直接红B模拟染料废水为研究对象,考察了臭氧化过程中染料溶液的吸光度和TOC的变化,同时利用离子色谱仪和GC/MS对染料的降解过程进行了分析,最后用发光细菌法检测了染料溶液急性毒性的变化。结果表明,臭氧对染料的降解符合一级反应动力学,20 min时对染料的脱色率达到99.2%;反应40 min后TOC减少32.55%,染料分子有97.8%的S被氧化为SO^2-₄,偶氮键被臭氧化为N₂,分子中的仲胺基小部分转化成游离NH⁺₄和NO^-₃;在臭氧化过程前期新生成的醛类和酰胺类物质使溶液急性毒性迅速上升,25 min后溶液毒性开始逐渐下降。     

壳聚糖对酸性染料的吸附性能研究

采用壳聚糖为吸附剂,研究了壳聚糖对兰纳洒脱酱红B(ABB)和尼龙山黄N-3RL(NYN)两种酸性染料模拟废水的吸附性能.在染料废水初始质量浓度为100 mg/L、体积为50 mL的条件下,壳聚糖对两种染料废水的最佳吸附条件:壳聚糖脱乙酰度为75%,壳聚糖粒径为0.054～0.076 MM,壳聚糖加入量为20 mg,搅拌时间为2.0 h,搅拌速率为400 r/min,废水pH为6,ABB废水温度为10～30 ℃,NYN废水温度为20-50℃.在最佳的吸附条件下,壳聚糖对ABB和NYN的吸附容量分别为244.45 mg/g和239.14 mg/g.壳聚糖对ABB的吸附较符合Freundlich方程,对NYN的吸附较符合Langmuir方程.     

基于利益相关方分析法的规划环评公众参与研究

采用利益相关方分析法,并依据<中华人民共和国环境影响评价法>、<环境影响评价公众参与暂行办法>等相关法律法规要求,遵循随机性原则和利益相关性原则,确定参与规划环境影响评价(简称规划环评)的公众范围,着重分析规划环评中相关方利益诉求.以某电石化工产业基地规划环评为例,通过规划环评的公众参与,分析利益相关方的共同点、关心点和矛盾点,并围绕各利益中心结合法律、法规设置了不同类型的问卷调查表,根据调查数据分析结果提出规划调整建议,解决了规划环评中利益相关方面临的问题.研究表明,利益相关方分析能够反映规划的环境不合理性,有助于规划的调整与优化.