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Short-Term Influence of Herbicide Quinclorac on Enzyme Activities in Flooded Paddy Soils

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Pedosphere 2004年第1期14卷 71-76页

作者： lüzhen-Mei MINHang YEYang-Fang CollegeoflifeSciences ZhejiangUniversityHangzhou310029（China）

The influence of quinclorac (3,7-dichloroquinoline-8-carboxylic acid) on enzyme activities in flooded paddy soils was assessed under laboratory conditions. The enzymes differed markedly in their response to quinclorac. Quinclorac inhibited proteinase, hydrogen peroxidase, phosphorylase, and urease *** higher the concentration of quinclorac applied, the more significant the inhibition to these observed activities with a longer time required to recover to the level of the control. However, soils supplemented with quinclorac were nonpersistent for proteinase, phosphorylase and urease as opposed to soils without quinclorac. Dehydrogenase activity was also sensitive to quinclorac. Three soil samples with concentrations of quinclorac higher than 1 μg g-1 soil declined to less than 20% of that in the control. However, the highest dehydrogenase activity (up to 3.28-fold) was detected in soils with 2 μg g-1 soil quinclorac on the 25th day after treatment. Quinclorac had a relatively mild effect on saccharase activity at the concentrations used in this experiment and a stimulatory one on soil respiration when added to soil at normal field *** it was inhibited at higher concentrations in paddy soils. Quinclorac is still relatively safe to the soil ecosystem when applied at a normal concentration (0.67 μg g-1 dried soil) but may have some effects on soil enzymes at higher concentrations.

关键词： flooded paddy soil quinclorac soil enzyme activity soil respiration

Characterization of a Strain Capable of Degrading a Herbicide Mixture of Quinclorac and Bensulfuronmethyl

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Pedosphere 2008年第5期18卷 554-563页

作者： lǖ zhen-Mei lI Zi-Mu SANG li-Ya MIN Hang College of life Sciences Zhejiang University Hangzhou 310058 （China）

A bacterial strain,designated as lS,was isolated from a contaminated soil and was found to be capable of utilizing quinclorac,bensulfuronmethyl,and a mixture of the two as carbon and energy sources for growth. Strain lS was identified as Ochrobactrum sp. based on its physiological-biochemical properties,16S rDNA sequences,and phylogenetic analysis. The extent of degradation of quinclorac and bensulfuronmethyl at initial concentrations of 1.5 and 0.1 g l-1 was 90% and 67%,respectively,as measured by high performance liquid chromatography(HPlC) . When a herbicide mixture of 0.34 g l-1 quinclorac and 0.02 g l-1 bensulfuronmethyl was applied as carbon sources,quinclorac and bensulfuronmethyl were degraded at 95.7% and 67.5%,respectively. It appears that quinclorac is utilized more easily in a mixture than in a single state. The optimal temperature for growth of strain lS was 37 ℃. Strain lS grew well at pH 6 to 9 and had the highest degradation level for quinclorac and bensulfuronmethyl at an initial pH of 7 and 8,respectively. Addition of 0.25 g l-1 yeast extract could promote the growth and extent of degradation of quinclorac and bensulfuronmethyl by strain lS. Strain lS also showed the capability to degrade other aromatic compounds such as catechol,propisochlor,4-chloro-2-methylphenoxyacetic acid sodium(MCPA-Na) and imazethapy. The isolate lS shows a huge potential to be used in bioremediation for treating complex herbicide residues.

关键词： bensulfuronmethyl degradation herbicide mixture Ochrobactrum sp. quinclorac

Multiple genetic alterations and behavior of cellular biology in gastric cancer and other gastric mucosal lesions:*** infection,histological types and staging

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World Journal of Gastroenterology 2000年第6期6卷 848-854页

作者： Heng Jun Gao lian zhen Yu Jian Feng Bai Yan Shen Peng Gu Sun Han lin Zhao Kun Miu Xiu zhen lü Xiao Yong Zhang Zhi Quan Zhao Department of Gastroenterology The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Department of Surgery The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China Renji Hospital Shanghai Second Medical UniversityShanghai Institute of Digestive DiseaseShanghai 200001China

AIM To investigate the expression of multiplegenes and the behavior of cellular biology ingastric cancer（GC）and other gastric mucosallesions and their relations to Helicobacter pylori（***）infection,tumor staging andhistological *** Three hundred and twenty-sevenspecimens of gastric mucosa obtained viaendoscopy or surgical resection,and ABCimmunohistochemical staining were used todetect the expression of p53,p16,Bcl-2 andCOX-2 *** was determined byrapid urea test combined with pathologicalstaining or14C urea breath *** image analysis was performed in 66 patients withintestinal metaplasia（IM）and/or dysplasia（Dys）.In 30 of them,both cancer and theparacancerous tissues were obtained at the timeof *** pattern,tumor staging,lymph node metastasis,grading ofdifferentiation and other clinical data werestudied in the medical *** p16 expression of IM or Dys wassignificantly lower in positive *** chronicatrophic gastritis（CAG）than those withnegative ***（CAG:54.8% vs 88.0%,IM:34.4% vs 69.6%,Dys:23.8% vs 53.6%,allP<0.05）,Bcl-2 or COX-2 expression of IM orDys in positive *** cases was significantlyhigher than that without ***（Bcl-2:68.8%vs23.9%,90.5% vs 60.7%;COX-2:50.0% vs10.8%,61.8% vs 17.8%;all P<0.05）.Themean number of most parameters of cellularimage analysis in positive *** group wassignificantly higher than that in negative *** group（Ellipser:53±14,40±12μm,Area1:748±572,302±202 μm2,Area2:3050±1661,1681±1990 μm2,all P<0.05;Ellipseb:79±23,58±15 μm,Ratio1:22%±5%,13%±4%,Ratio2:79%±17%,53%±20%,all P<0.01）.There was significant correlation between Bcl-2and histologic pattern of gastric carcinoma,andbetween COX-2 and tumor staging or lymph nodemetastasis（Bcl-2:75.0% vs 16.7%;COX-2:76.0% vs 20.0%,79.2% vs 16.7%;allP<0.05）.CONClUSION p1l6, Bcl-2, and COX-2 but not p53 gene may play a role in t

关键词： stomach neoplasms gastric mucosa/injuries precancerous conditions gene expression Helicobacter pylori gastroscopy immunohistochemistry neoplasm staging

Variations in laboratory-Scale Actinomycete Communities Exposed to Cadmium as Assessed by Denaturing Gradient Gel Electrophoresis Profiles

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Pedosphere 2010年第2期20卷 174-184页

作者： YUAN Hai-Ping,MIN Hang 2,lIU Ji,YAN Bo and l zhen-Mei College of life Science,Zhejiang University,Hangzhou 310058 (China) College of life Science Zhejiang University Hangzhou 310058 (China)

The actinomycete populations and functions in cadmium （Cd） contaminated soil were investigated by the cultivation- independent molecular methods. The genomic DNA was extracted and purified from soil adulterated with various con- centrations of Cd in the laboratory. The partial 16S rDNA genes were amplified by polymerase chain reaction （PCR） using specific primers bound to evolutionarily conserved regions within these actinomycete genes. The diversity in PCR- amplified products, as measured by denaturing gradient gel electrophoresis （EGGE）, was used as a genetic fingerprint of the population. Principle component analysis and Shannon-Weaver diversity index （H） analyses were used to analyze the DGGE results. Results showed that the two principal components accounted for only a low level of the total variance. The value H in contaminated soil was lower than that in the control at later stages of cultivation, whereas at earlier stages it was higher. Among the six sampling time points, the first, fifth and sixth weeks had the highest values of H. Significantly negative correlations between bioavallable Cd concentration and H values existed in the samples from weeks 2 （R = 0.929, P 〈 0.05） and 4 （R = 0.909, P 〈 0.05）. These results may shed light on the effect of Cd on the soil environment and the chemical behavior and toxicity of Cd to actinomycetes.

关键词： denaturing gradient gel electrophoresis genes principal component analysis Shannon-Weaver diversity index

Dual-layered metasurfaces for asymmetric focusing

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Photonics Research 2020年第6期8卷 830-843页

作者： BINGSHUANG YAO XIAOFEI ZANG zhen l lIN CHEN JINGYA XIE YIMING ZHU SONGlIN ZHUANG Terahertz Technology Innovation Research Institute Terahertz Spectrum and Imaging Technology Cooperative Innovation CenterShanghai Key Laboratory of Moderm Optical SystemUniversity of Shanghai for Science and TechnologyShanghai 200093China Shanghai Institute of Intelligent Science and Technology Tongi UniversityShanghai 200092China

Asymmetric transmission,defined as the difference between the forward and backward transmission,enables a plethora of applications for on-chip integration and ***,the traditional method for asymmetric transmission is to control the propagation direction of the waves,hindering further ***,a kind of two-dimensional metamaterials,have shown an unprecedented ability to manipulate the propagation direction,phase,and polarization of electromagnetic *** we propose and experimentally demonstrate a metasurface-based directional device consisting of a geometric metasurface with spatially rotated microrods and metallic gratings,which can simultaneously control the phase,polarization,and propagation direction of waves,resulting in asymmetric focusing in the terahertz *** dual-layered metasurfaces for asymmetric focusing can work in a wide bandwidth ranging from 0.6 to 1.1 *** flexible and robust approach for designing broadband asymmetric focusing may open a new avenue for compact devices with potential applications in encryption,information processing,and communication.

关键词： asymmetric layered surfaces

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro letters 2025年第2期17卷 548-565页

作者： Ming‑Yuan Yu Jing Wu Guang Yin Fan‑zhen Jiao Zhong‑zhen Yu Jin Qu Beijing Key laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

粘弹性阻尼材料力学参数测试实验用双边附加自由结构阻尼试件设计方法研究

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振动与冲击 2014年第5期33卷 102-108页

作者：王超吕振华清华大学汽车工程系北京100084

悬臂梁弯曲共振法测量粘弹性阻尼材料力学参数的实验中常以双边附加自由结构阻尼试件为实验对象。实验中试件设计的合理程度直接影响实验的测试精度。为了指导试件设计,通过灵敏度分析提出了影响系数的概念,并将其应用于分析试件的厚度... 详细信息

悬臂梁弯曲共振法测量粘弹性阻尼材料力学参数的实验中常以双边附加自由结构阻尼试件为实验对象。实验中试件设计的合理程度直接影响实验的测试精度。为了指导试件设计,通过灵敏度分析提出了影响系数的概念,并将其应用于分析试件的厚度比、共振频率比、密度比、损耗因子等参数的测量误差对粘弹性材料力学参数测试精度的影响中,进而对试件的设计提出一些有重要意义的技术规范。最后,基于悬臂梁弯曲共振法获取粘弹性材料力学参数的实验,分析了双边自由阻尼结构试件的适用范围。

关键词：粘弹性材料试件设计影响系数灵敏度分析结构阻尼

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适配体纳米金比色分析技术研究进展

光谱学与光谱分析 2014年第8期34卷 2040-2046页

作者：刘金钏吕珍珍陈爱亮中国农业科学院农业质量标准与检测技术研究所北京100081

核酸适配体作为一种生物识别分子,其本质是一段单链DNA或RNA,折叠形成特定的二级、三级构象后与靶标分子以高亲和力高特异性结合。纳米金具有强烈的粒子间距光学效应,其在分散状态下呈红色,发生凝聚后变为蓝色。适配体可以通过共价偶联... 详细信息

核酸适配体作为一种生物识别分子,其本质是一段单链DNA或RNA,折叠形成特定的二级、三级构象后与靶标分子以高亲和力高特异性结合。纳米金具有强烈的粒子间距光学效应,其在分散状态下呈红色,发生凝聚后变为蓝色。适配体可以通过共价偶联或静电吸附与纳米金结合,通过结合靶标来控制纳米金的颜色变化,从而提供了一种简单、快速、灵敏、可以肉眼观察的快速分析技术。综述了适配体纳米金比色分析技术的研究进展,通过对不同方法比较和讨论,提出了未来的研究方向。

关键词：适配体纳米金比色单链DNA检测

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基于进化算法的多用户检测器

电子与信息学报 2006年第2期28卷 223-227页

作者：阎石吕振肃兰州大学信息科学与工程学院兰州730000

粒子群算法PSO遗传算法(Particle Swarm Optimization)是由Kennedy和Eberhart于1995年提出的一种新的进化算法,PSO能够以一种更简便、快速的方式来完成和遗传算法(GA)一样的功能。本文在PSO算法思想的基础上提出了两种新的多用户检测算... 详细信息

粒子群算法PSO遗传算法(Particle Swarm Optimization)是由Kennedy和Eberhart于1995年提出的一种新的进化算法,PSO能够以一种更简便、快速的方式来完成和遗传算法(GA)一样的功能。本文在PSO算法思想的基础上提出了两种新的多用户检测算法:BEP(Binary Evolution Programming)算法,BPSO(Binary PSO,BPSO)算法。分别基于这两种算法构造了新的多用户检测器。仿真结果表明,这两种新的多用户检测器的抗误码性能比传统多用户检测器和基于遗传算法的多用户检测器都好,并且新的检测器的收敛速度明显比遗传算法检测器快。

关键词：多用户检测遗传算法进化规则粒子群优化算法