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柠檬醛对黄曲霉质膜物理损伤机制的研究

武汉大学学报（理学版） 2002年第2期48卷 217-222页

作者：罗曼蒋立科邹国林安徽农业大学生物工程系安徽合肥23003 武汉大学生命科学学院湖北武汉430072

通过反射干涉对比显微技术和快速图像分析技术,捕获细胞质膜外光晕变化和细胞周边边缘激发变化的信息,并采用闪烁本征模式分解测定柠檬醛作用于黄曲霉质膜前后各模式（m=0,1,2.所对应的平均平方振幅、剪切弹性μ和弹性弯曲模量Kc,与理... 详细信息

通过反射干涉对比显微技术和快速图像分析技术,捕获细胞质膜外光晕变化和细胞周边边缘激发变化的信息,并采用闪烁本征模式分解测定柠檬醛作用于黄曲霉质膜前后各模式（m=0,1,2.所对应的平均平方振幅2.>、剪切弹性μ和弹性弯曲模量Kc,与理论模式光谱相比,研究柠檬醛损伤质膜的物理机制.结果表明,m=1的平动模式主导了光晕波谱,其平均平方振幅呈双指数衰变,该模式几乎与剪切弹性无关,即μ=0;弹性弯曲模量Kc的最小和最大值分别为9.45×10-18J和5.43×10-17J,与柠檬醛的浓度成正相关性.揭示该醛对黄曲霉质膜的损伤,除改变膜的选择通透性和电导率外,同时使质膜平动模式的平均平方振幅呈双指数衰变,弹性弯曲模量Kc增加,从而降低膜伸缩的弹性.

关键词：物理损伤机制柠檬醛黄曲霉质膜反射干涉对比显微镜本征模式分解快速图像分析技术通透性电导率

Indirect Determination of Ascorbic Acid with Ammonium Sulfate and Isopropyl Alcohol by Extraction-flotation of Copper

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Chinese Chemical Letters 2003年第9期14卷 983-986页

作者： Shao Mei WANG, Yun XING, Quan Min LIcollege of Chemistry and environmental Science, Henan Normal University, Key Laboratory of environmental Science and engineering Education Commission of Henan Province, Xinxiang453002.department of Chemistry, Anyang Normal college, Anyang 455000 college of Chemistry and environmental Science Henan Normal University Key Laboratory of Environmental Science and Engineering Education Commission of Henan Province Xinxiang 453002 department of Chemistry Anyang Normal College Anyang 455000

A new method of indirect determination of ascorbic acid(Vc) with ammonium sulfate and isopropyl alcohol by extraction-flotation of copper is studied in this paper. It shows that a small amount of Cu(Ⅱ) can be reduced to Cu( Ⅰ ) by Vc, then Cu(Ⅰ) reacted with the SCN-, which precipitated on the interface of isopropyl alcohol and H2.. A good linear relationship is observed between the flotation yield(E) of Cu( Ⅱ) and the amount of Vc. The detection limit for Vc is 1.76μg/mL. The method is simple, rapid (5 min), but suffers from little interference of common anions and cations. It has been successfully applied for the determination of Vc in fruits.

关键词： Ascorbic acid isopropyl alcohol extraction and flotation.

Impact of Soil Water Flux on Vadose Zone Solute Transport Parameters

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Pedosphere 2000年第4期10卷 323-332页

作者： CHENXIAOMIN M．VANCLOOSTER 等 collegeofResourcesandenvironmentalSciences nanjingAgriculturalUniversityNanjing210095China departmentofenvironmentalSciencesandLandUsePlanning UniversityCatholiquedeLouvainB－1348

The transport processes of solutes in two soil columns filled with undisturbed soil material collected from an unsaturated sandy aquifer formation in Belgium subjected to a variable upper boundary condition were identified from breakthrough curves measured by means of time domain reflectometry (TDR). Solute breakthrough was measured with 3 TDR probes inserted into each soil column at three different depths at a 10 minutes time interval. In addition, soil water content and pressure head were measured at 3 different depths. Analytical solute transport models were used to estimate the solute dispersion coefficient and average pore-water velocity from the observed breakthrough curves. The results showed that the analytical solutions were suitable in fitting the observed solute transport. The dispersion coefficient was found to be a function of the soil depth and average pore-water velocity, imposed by the soil water flux. The mobile moisture content on the other hand was not correlated with the average pore-water velocity and the dispersion coefficient.

关键词： dispersion coefficient pore-water velocity solute transport time domain reflectometry (TDR)

MAPKs and Mst1/Caspase-3 pathways contribute to H2. phosphorylation during UVB-induced apoptosis

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Science china(Life Sciences) 2010年第6期53卷 663-668页

作者： LU ChengRong1SHI Ying1LUO Yuan1,DUAN LianNing1,HOU Yong2.HU HongBo3,WANG Zhe1 & XIANG PeiDe1 1Aviation Medicine Research Laborabory,General Hospital of Air Force,Beijing 100142.china 2.department of Pharmacology,Hebei North University,Zhangjiakou 075000,china 3 Nutrition and Food Safety Center,college of Food Science and Nutritional engineering,china agricultural University,Beijing 100083,china 1. Aviation Medicine Research Laborabory General Hospital of Air Force Beijing 100142 China2. Department of Pharmacology Hebei North University Zhangjiakou 075000 China3. Nutrition and Food Safety Center College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 China

Apoptosis is a highly coordinated or programmed cell suicide mechanism in *** modification is associated with nuclear events in apoptotic *** H2. phosphorylation at serine 14 (Ser14) catalyzed by Mst1 kinase has been linked to chromatin condensation during *** report that activation of MAPKs (ERK1/2.JNK1/2.and p38) together with Mst1 and caspase-3 is required for phosphorylation of H2. (Ser14) during ultraviolet B light (UVB)-induced *** can trigger activation of MAPKs and induce H2. phosphorylation at Ser14 but not acetylation in a time-dependent *** of ERK1/2.JNK1/2.or p38 activity blocked H2. phosphorylation (Ser14).Furthermore,caspase-3 was activated by UVB to regulate Mst1 activity,which phosphorylates H2. at Ser14,leading to chromatin *** inhibition of caspase-3 activity reduced Mst1 activation and partially inhibited H2. phosphorylation (Ser14),but ERK1/2.JNK1/2.and p38 activities were not *** together,these data revealed that H2. phosphorylation is regulated by both MAPKs and caspase-3/Mst1 pathways during UVB-induced apoptosis.

关键词： apoptosis H2. MAPK Mst1

Impact of Soil Fumigation Practices on Soil Nematodes and Microbial Biomass

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Pedosphere 2004年第3期14卷 387-393页

作者： CAO Zhi—Ping YU Yong—Li CHEN Guo-Kang R.DAWSON department of Ecology and Ecological engineering College of Resources and Environmental ScienceChina Agricultural UniversityBeijing 100094(China).

This study was designed to understand the impact of methyl bromide (MB) (CH3Br) and its alternatives on both free-living and root-knot nematodes in the soil. A randomized complete block experiment with six treatments and 4 replicates (each replicate in a separate greenhouse) was established in Qingzhou, Shandong Province, china. In addition to MB and untreated control (CK) treatments there were four alternative soil fumigation practices including MB+virtually impermeable films (VIF), metam sodium (MS), MS +VIF and soil solarization combined with selected biological control agents (SS+BCA). Two tomato (Lycopersicum esculentum Mill.) cultivars, cv. Maofen-802.from the Xian Institute of Vegetable Science, china, and cv. AF179 Brillante from the Israeli Hazera Quality Seeds, were selected as test crops. The results indicated that Rhabditidae was the most dominant population with percentage abundance as high as 85% of the total number of identified free-living nematodes, followed by that of Cephalobidae. Methyl bromide and its alternatives except for the non-chemical SS+BCA treatment controlled the target pest, root-knot nematodes. Also, the impact of the three chemical alternatives on free-living nematode number and functional group abundance was similar to the impact associated with a typical methyl bromide application. Chemical fumigation practices, especially that with MB, significantly reduced the number of nematodes in the soil and simultaneously significantly reduced the number of nematode genera thereby reducing nematode diversity. All the four soil chemical fumigation activities decreased soil microbial biomass and had an obvious initial impact on microorganism biomass. Furthermore, both plant-parasitic and fungivore nematodes were positively correlated with soil microbial biomass.

关键词： methyl bromide microbial biomass nematode soil fumigation

Monocrotophos Molecularly Imprinted Microspheres Prepared by Precipitation Polymerization in Acetonitrile

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稀有金属材料与工程 2006年第S3期 621-622页

作者： Shoulei Yan~(1,2. Zhixian Gao~1 Yanjun Fang~1 Yiyong Cheng~1 (1.Institute of Hygiene and environmental Medicine,Academy of Military Medical Sciences,Tianjin 300050,china) (2.{2. of Food Science,Huazhong agricultural University,Wuhan 430070,china)

Molecularly imprinted microspheres (MIP) for monocrotophos have been prepared by precipitation polymerization in acetonitrile (ACN) 60℃,2. h,using methacrylic acid (MAA),ethylene glycol dimethacrylate (EGDMA) and 2. 2.azobisiobutyronitrile (AIBN) as functional monomer,cross-linker and initiator,*** recognition mechanism was elucidated by UV-vis spectra and computer *** binding experiment was employed to investigate the rebinding properties,Scatchard analysis showed that specific binding sites formed in the imprinted microspheres,and there were two kinds of binding sites,one was high binding sites,the other was low binding *** microspheres can be useful affinity absorbent used for organophosphorus pesticides separation and purification in food and environmental analysis.

关键词： monocrotophos molecular imprinting microspheres precipitation polymerization

Soil Fertility Indices of Citrus Orchard Land Along Topographic Gradients in the Three Gorges Area of china

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Pedosphere 2011年第6期21卷 782-792页

作者： WU Dian-Ming YU Yuan-Chun XIA Li-Zhong YIN Shi-Xue YANG Lin-Zhang college of Forest Resources and Environment Nanjing Forestry University Nanjing 210037 （China） State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） college of environmental Science and {2. Yangzhou University Yangzhou 22500g （China）

In the Three Gorges Area of china, soil erosion and the resultant non-point source pollution and ecological degradation have endangered agricultural ecosystems and fresh water reservoirs. Although efforts have been undertaken to reduce soil and water losses from slope land used for citrus production, information on the effects of management practices on soil fertility indices is either limited or nonexistent. This study was conducted to compare the effects of 10 years of various management practices, citrus intercropped with white clover (WC), citrus mulched with straw (SM), citrus intercropped with contour hedgerows (CH), citrus orchard land with impermeable membrane (IM), and citrus intercropped with wheat (Triticum aestivum) and peanut (Arachris hypogaea) (WP), as treatments on soil fertility indices with that of the conventional citrus management (CM). Results showed that the soil organic carbon, total and available nitrogen, available potassium, and water-stable aggregate (> 0.2. mm) contents at the 0–5 cm depth were higher for the WC and SM treatments than the CM treatment. There was also spatial variation in soil fertility along slopes of the WC and SM treatments. The soil total and available nitrogen, phosphorus, and potassium, and water-stable aggregate (> 0.2. mm) contents at both the 0–5 and 5–2. cm depths were higher for the CH and IM treatments than the CM treatment. The average soil available nitrogen and available potassium contents were higher for the WP treatment than the CM treatment, but the WP treatment had little effect on the soil organic carbon, total nitrogen, and water-stable aggregate (> 0.2. mm) contents. These suggested that white clover intercropping and straw mulching were the most effective approaches to improve soil fertility in citrus orchard land of the Three Gorges area.

关键词： intercropping slope land soil nutrients soil water-stable aggregates straw mulching

Removal of Pyrene from Contaminated Soils by White Clover

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Pedosphere 2009年第2期19卷 265-272页

作者： XU Sheng-You CHEN Ying-Xu LIN Kuang-Fei CHEN Xin-Cai LIN Qi LI Feng WANG Zhao-Wei department of environmental {2. Zhejiang University Hangzhou 310029 China college of Life and Environment Huangshan University Huangshan 245041 China School of Resource and environmental engineering East China University of Science and Technology Shanghai 200237 China

Phytoremediation has been used as an emerging technology for remediation of soil contamination with polycyclic aromatic hydrocarbons(PAHs),ubiquitous persistent environmental pollutants derived from natural and anthropogenic processes,in the last *** this study,a pot experiment was conducted to investigate the potential of phytoremediation of pyrene from spiked soils planted with white clover(Trifolium repens)in the greenhouse with a series of pyrene concentrations ranging from 4.2. to 365.38 mg *** results showed that growth of white clover on pyrenecontaminated soils was not *** removal of pyrene from the spiked soils planted with white clover was obviously higher than that from the unplanted *** the end of the experiment(60 d),the average removal ratio of pyrene in the spiked soils with white clover was 77%,which was 31%and 57%higher than those of the controls with or without micobes, *** roots and shoots of white clover took up pyrene from the spiked soils and pyrene uptake increased with the soil pyrene ***,the plant-enhanced dissipation of soil pyrene may be the result of plant-promoted microbial degradation and direct uptake and accumulation of pyrene by white clover were only a small part of the pyrene *** factors of pyrene(BCFs,ratio of pyrene,on a dry weight basis,in the plant to that in the soil)tended to decrease with increase in the residual soil pyrene ***,removal of pyrene in the contaminated soils was feasible using white clove.

关键词： microbial degradation phytoremediation plant uptake and accumulation pyrene white clover

CONTROLLED RELEASE FROM PDMAEMA GELS PREPARED BY GAMMA RADIATION

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Chinese Journal of Polymer Science 2002年第5期20卷 409-412页

作者： Ning Liu Min Yi Shuang-ji Chen Hong-fei Ha college of Chemistry and Molecular engineering Peking University Beijing 100871,{2. department of Biochemistry college of Applied Arts and Science, Beijing Union University Beijing 100083.{2. Peking Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China Beijing Union Univ Coll Appl Arts & Sci Dept Biochem Beijing 100083 Peoples R China

Poly(N,N-dimethylaminoethyl methacrylate) (polyDMAEMA) hydrogels prepared by gamma-irradiation showed obvious temperature-sensitivity in a temperature range of 38-40degreesC and pH-sensitivity at pH=2.5. They also showed electric response behavior although it was not typical. The hydrogels were used in controlled release at different pH, temperature, and electric voltage. The release rates of methylene blue (MB) from the gels at 52.egreesC and pH=1.2. were faster than those at 2.degreesC and pH=10.56, respectively. In addition, the release rate at a field voltage of 5.0 was also faster than that without electric field.

关键词： poly(N,N-dimethylaminoethyl methacrylate) environmental sensitivity hydrogel controlled release