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酞酸酯曝气生物降解规律的研究

四川大学学报（工程科学版） 2002年第1期34卷 72-76页

作者：夏凤毅郑平周琪冯孝善浙江大学环境工程系浙江杭州310029 同济大学环境污染控制与废物资源化国家重点实验室上海200092

采用曝气法模拟废水处理实验测试了酞酸酯类化合物的曝气生物降解行为 ,结果表明 ,降解符合一级动力学方程 ,酞酸酯的降解速率常数 (kb)与其烷基链长度之间存在良好的相关性 ,其降解速率常数随着化合物分子烷基链的增加而减小 ,降解反... 详细信息

采用曝气法模拟废水处理实验测试了酞酸酯类化合物的曝气生物降解行为 ,结果表明 ,降解符合一级动力学方程 ,酞酸酯的降解速率常数 (kb)与其烷基链长度之间存在良好的相关性 ,其降解速率常数随着化合物分子烷基链的增加而减小 ,降解反应速率常数与碱基链的长度变化呈曲线关系 ,并且可以用建立的相关方程。在一定范围内 ,酞酸酯类化合物的生物降解速率随自身浓度的增加而增大 ,达到某一耐受浓度后 ,开始减小 ;低浓度的乳化剂对酞酸酯类化合物的生物降解基本上无抑制作用 ,而外加的高浓度的中间体邻苯二甲酸则有很强的抑制作用。

关键词：酞酸酯曝气衰变法生物降解环境污染物废水处理

Effect of Waterlogged and Aerobic Incubation on Enzyme Activities in Paddy Soil

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Pedosphere 2006年第4期16卷 532-539页

作者： WANG Xiao-Chang LU Qin Department of Tea Science College of Agriculture and Biotechnology Zhejiang University Hangzhou 31002g （China） Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）

An incubation experiment with soil water content treatments of 0.15 （W1）, 0.20 （W2）, and 0.40 （W3） g g^-1 soil was carried out for two months to investigate the activities of important enzymes involved in C, N, P, and S cycling in a paddy soil from the Taihu Lake region, China, under waterlogged and aerobic conditions. Compared with air-dried soil, waterlogging resulted in a significant decrease （P ≤ 0.05） of fluorescein diacetate （FDA） and /3-D-glucosidase activities, and this effect was enhanced with increasing waterlogging time. Waterlogging also significantly inhibited （P ≤ 0.05） arylsulfatase as well as alkaline and acid phosphatase activities, but did not decrease the activities with the increase in waterlogging time. Short-term waterlogging did not affect urease activity, but prolonged waterlogging decreased it markedly. In contrast, the aerobic incubation （W1 and W2 treatments） significantly increased （P ≤ 0.05） FDA, alkaline phosphatase, and /3-D-glucosidase activities. With aerobic treatments the activities of FDA and alkaline phosphatase increased with incubation time, whereas /3-D-glucosidase activity decreased. A significant difference （P ≤ 0.05） was usually observed between the W1 and W2 treatments for the activities of FDA as well as alkaline and acid phosphatase; however,/3-D-glucosidase and urease were usually not significant （P ≤ 0.05）. No activity differences were observed between waterlogging and aerobic incubation for arylsulfatase and urease.

关键词： aerobic incubation enzyme activity paddy soil waterlogging

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社区主义:公共伦理建设的新走向

上海交通大学学报（哲学社会科学版） 2002年第1期10卷 31-35页

作者：余潇枫张东和浙江大学国际文化学院浙江杭州310027

当代中国正处在以城市化为主导的社会转型的关键时期 ,社会出现了种种不协调 ,需要相应价值尺度来引导。而以国家理性为价值尺度的“国家主义”在中国正趋向衰微 ,以个人理性为终极价值尺度的“个人主义”在中国无法植根 ,造成了社会公... 详细信息

当代中国正处在以城市化为主导的社会转型的关键时期 ,社会出现了种种不协调 ,需要相应价值尺度来引导。而以国家理性为价值尺度的“国家主义”在中国正趋向衰微 ,以个人理性为终极价值尺度的“个人主义”在中国无法植根 ,造成了社会公共伦理的“空场”,从而说明以公共理性为核心 ,以“个人自由加公共利益”为精神实质的“社区主义”作为一种新的社会精神价值取向应时而生。

关键词：社区主义公共伦理国家主义个人主义中国社会转型期城市化

Effect of Management Practices on Seasonal Dynamics of Organic Carbon in Soils Under Bamboo Plantations

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Pedosphere 2006年第4期16卷 525-531页

作者： ZHOU Guo-Mo XU Jian-Ming JIANG Pei-Kun College of Resources and Environment Zhejiang University Hangzhou 31002g （China） Zhejiang Forest College Lin＇an 311300 （China）

Soil samples for conventional management (CM) and intensive management (IM) practices were taken over a year at 2-month intervals to determine the effect of management practices on soil organic carbon (SOC) and to quantify seasonal dynamics in SOC for bamboo (Phyllostachys pubescens Mazel ex H. de Lehaie) stands. The results with IM compared to CM showed large decreases in total organic carbon (TOC), microbial biomass carbon (MBC), water-soluble organic carbon (WSOC), and the MBC/TOC ratio in the soils. With all IM plots in the 0-20 cm depth across sampling periods, average decreases compared with CM were: TOC, 12.1%; MBC, 26.1%; WSOC, 29.3%; the MBC/TOC ratio, 16.1%; and the WSOC/TOC ratio, 20.0%. Due to seasonal changes of climate, seasonal variations were observed in MBC and WSOC. Soil MBC in the 0-20 cm depth in September compared to May were 122.9% greater for CM and 57.6% greater for IM. However, due primarily to soil temperature, soil MBC was higher during the July to November period, whereas because of soil moisture, WSOC was lower in July and January. This study revealed that intensive management in bamboo plantations depleted the soil C pool; therefore, soil quality with IM should be improved through application of organic manures.

关键词： bamboo (Phyllostachys pubescens) conventional management dynamics intensive management soil organic carbon

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板栗多酚氧化酶性质的研究

上海交通大学学报（农业科学版） 2001年第3期19卷 174-178页

作者：叶兴乾张贵平浙江大学食品科学与营养系杭州310029 红塔烟草有限责任公司玉溪653100

为解决板果加工褐变的问题，采用分光光度法对板采果肉中多酚氧化酶的性质进行了研究，分别求出该酶的适宜温度为40～60℃，最适pH值为4．0和7．0，Vmax=0．93吸光度／min，Km＝76．15mmol／L。并探讨了该酶的热稳定性以及抑制剂氛化钠... 详细信息

为解决板果加工褐变的问题，采用分光光度法对板采果肉中多酚氧化酶的性质进行了研究，分别求出该酶的适宜温度为40～60℃，最适pH值为4．0和7．0，Vmax=0．93吸光度／min，Km＝76．15mmol／L。并探讨了该酶的热稳定性以及抑制剂氛化钠、柠檬酸、四硼酸钠、亚硫酸氢钠和杭坏血酸对酶活力的影响。

关键词：板栗多酚氧化酶性质

Periodic void arrays in silica and BK7 glasses induced by tight-focused femtosecond laser pulses

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Periodic void arrays in silica and BK7 glasses induced by ti...

Effect of Organic Acids and Protons on Release of Non-Exchangeable NH_4^+ in Flooded Paddy Soils

2006年全国强场激光物理会议

作者： Haiyi Sun Jue Song Chengbin Li Jian Xu Xinshun Wang Jianrong Qiu Ya Cheng Zhizhan Xu State Key Laboratory of High Field Laser Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,P.O.Box 800-211,Shanghai 201800,P.R.China ~2Department of Materials Science and Engineering,Zhejiang University,hangzhou 31002.7,China

＜正＞We demonstrate self-fabricated periodic void arrays inside fused silica and BK7 glass induced by tight focusing（NA=0.9）femtosecond laser pulses under the condition of deep focal *** effects of the focusing conditions,including laser energy,pulse number and focal depth on the shape and the whole length of the fabricated void arrays were *** divided single void was easily fabricated when multiple pulses were irradiated.A single laser pulse tended to induce a staged linearly drawn shape,and the staged character showed more evident with increasing focusing *** whole length of microstructure was strongly dependent on the depth of the focal point,pulse energy and pulse number,which became longer with the increase of these parameters,but not infinite,it will decrease again as these parameters increase to a certain *** was more evident in silica glass than in BK7 glass due to the larger nonlinear refraction index of silica glass.

关键词： femtosecond laser fused silica BK7 glass void array whole length

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Pedosphere 2005年第3期15卷 273-280页

作者： ZHANGYong-Song SHAOXing-Hua LINXian-Yong H.W.SCHERER MinistryofEducationKeyLabofEnvronmentalRemediationandEcosystemHealth CollegeofNaturalResourcesandEnvironmentalScienceZhejiangUniversityHangzhou31002g（China） InstituteofPlantNutrition JniversityofBonnKarlrobert-Kreiten-Str13D-53115Bonn（Germany）

In a model experiment, which imitated the rhizosphere of rice, the effect of organic acids (oxalic acid, citric acid) and protons on the release of non-exchangeable NH4+ and the resin adsorption of N was studied in a paddy soil, typical for Zhejiang Province, China. Oxalic and citric acids under low pH conditions, in combination with proton secretion, favored the mobilization of NH4+ ions and increased resin adsorption of N. The release of non-exchangeable NH4+ was associated with less formation of iron oxides. These could coat clay minerals and thus hinder the diffusion of NH4+ ions out of the interlayer. Protons enhanced the release of NH4+, and then they could enter the wedge zones of the clay minerals and displace non-exchangeable NH4+ ions.

关键词： ammonium release exchange resin non-exchangeable ammonium paddy soil root exudates