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Competitive adsorption and mobility sequence of heavy metals in urban soils of southeastern China

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Journal of Environmental Sciences 2006年第2期18卷 329-333页

作者： ZHANG Ming-kui fang li-ping HUANG chang-yong Department of Natural Resource Sciences College of Natural Resource and Environmental Sciences Zhejiang University Hangzhou 310029 China

Heavy metals can be introduced into urban soils at the same time. Therefore, their selective retention and competitive adsorption by the soils become of major importance in determining their availability and movement throughout the soil. In this study, the availability and mobility of six heavy metals in eight urban soils collected from different cities of Zhejiang Province, southeastern China were assessed using distribution coefficients（Kd） and retardation factor（Rf）. The results showed that there were great differences in the Kd and Rfamong the tested soils. The adsorption sequences were Cr〉Pb〉Cu〉Cd〉Zn〉Ni, and the Kd decreased with increasing levels of metal addition. Ni generally has the lowest Rf values followed closely by Cd, and Zn whereas Cr and Pb reached the highest values. The results suggest that Ni and Zn have the highest mobility associated to the lowest adsorption, Cr and Pb present the opposite behavior. Correlation analysis indicates that soil pH, CaCO3 content, and cation exchange capacity （CEC） are key factors controlling the solubility and mobility of the metals in the urban soils.

关键词： competitive adsorption mobility sequence heavy metal urban soil

基于LabVIEW的微生物鉴定及药敏分析系统

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医疗卫生装备 2005年第A9期26卷 96-98页

作者：周琴雷长海李东方张乐平第二军医大学上海市200433

本文介绍了微生物鉴定及药敏系统的主要功能,阐述了基于虚拟仪器技术的软件设计特色,讨论了如何利用LabVIEW的模块实现数据库操作、串口通讯和实验数据的远程发布。

关键词：虚拟仪器 DB数据库串口通讯远程发布

In-situ liquid-cell TEM study of radial flow-guided motion of octahedral Au nanoparticles and nanoparticle clusters

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Nano Research 2018年第9期11卷 4697-4707页

作者： chang li Xin Chen Haiyang liu Jiali fang Xiaoqin Zhou School of Materials Science and Engineering East China University of Science and Technology Shanghai 200237 China Key Laboratory for Ultrafine Materials of Ministry of Education and Shanghai Key Laboratory of Advanced Polymeric Materials School of Materials Science and Engineering East China University of Science and Technology Shanghai200237 China

The dynamic behavior of octahedral gold nanopartides （NPs） and nanoparticle clusters （NPCs） in aqueous solution is studied by in-situ liquid-cell transmission electron microscopy （TEM）. The octahedral Au NPs/NPCs show preferential orientations in the liquid cell, due to the interaction with the SiNx window. The Au NPs show long-range reversible hopping and three-dimensional （3D） rotational motions in the liquid environment. At the same time, the Au NPCs and NPs perform slow stick-sUp and stick-roU motions, respectivel~ with a centripetal trend. The centripetal motions were explained by a liquid evaporation-induced radial flow model in which the NPCs/NPs trajectories are controlled by Stokes forces and surface friction by the silicon nitride window. The calculated radius-dependent force （Fc） on the NPCs/NPs shows a semi-linear correlation with the distance r between the NPCs/NPs and the center of mass, accompanied with stochastic fluctuations, in agreement with the model predictions. This work thus demonstrates the effectiveness of in situ liquid-cell TEM for the in-depth understanding of complicated liquid flow and force interactions in nanomaterials.

关键词： in situ transmissionelectron microscopy (TEM) nanoparticles nanoassembling nanoscale fluids trapping force

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西兰花苗中萝卜硫素合成的调控手段研究进展

食品科学 2025年第1期46卷 210-217页

作者：李翠方胜赵忠良刘海杰中国农业大学食品科学与营养工程学院北京100083 江苏新希望生态科技有限公司江苏徐州221150

萝卜硫素(sulforaphane,SFN)具有抗肿瘤、抗炎、抗氧化、减轻肥胖等多种生物学活性,在西兰花苗中含量最高,使西兰花苗在保健食品和药品开发方面具有广阔的应用前景。本文首先综述SFN在西兰花苗中的合成及降解过程,重点讨论在西兰花苗生... 详细信息

萝卜硫素(sulforaphane,SFN)具有抗肿瘤、抗炎、抗氧化、减轻肥胖等多种生物学活性,在西兰花苗中含量最高,使西兰花苗在保健食品和药品开发方面具有广阔的应用前景。本文首先综述SFN在西兰花苗中的合成及降解过程,重点讨论在西兰花苗生长阶段采用不同处理手段对SFN及其合成相关因子含量的影响,并对其作用机理进行总结分析,最后提出目前还存在的问题及对未来研究方向的展望,为提高植物源食品功能性的相关研究提供一定参考。

关键词：西兰花苗硫代葡萄糖苷萝卜硫素生成机理调控

Purification, Biological Activities, and Molecular Cloning of a Novel Mannose-Binding Lectin from Bulbs of Zephyranthes candida Herb （Amaryllidaceae）

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Journal of Integrative Plant Biology 2006年第2期48卷 223-231页

作者： Chuan-fang Wu Jian li Jie An li-Qing chang fang Chen Jin-Ku Bao College of life Sciences Sichuan University Chengdu 610064 China

A novel mannose-bindlng aggiutinln was purified from bulbs of Zephyranthes candida Herb by extraction, precipitation with 80% （NH4）2SO4, and ion-exchange chromatography on DEAE-Sepharose followed by gel flitration on Sephscryl S-100. The purified Z. candida agglutlnln （ZCA） migrated as a single band of 12 kDa on sodium dodecyi suifate-poiyecryiamide gel electrophoresis under reducing and non-reducing conditions. The apparent molecular mass of the iectln, as datermlned by gel filtration chromatography, was 48 kDa. The results Indicated that ZCA was composed of four Identical subunlts of 12 kDa each （homotetramerlc nature）. The ZCA agglutlhated rabbit erythrocytes, Escherichla coil and Saccharomyces cerevislae ceils at concentrations of 0.95, 1.90, and 31.30 μg/mL, respectively. Bloassays Indicated that ZCA has a significant effect on wheat aphid survival. Mortality after 7 d was 〉 90% at 0.26%. A degenerate primer was designed In accordance with the N-terminal partial sequence of purified ZCA. The full-length cDNA was cloned by 3＇- and 5＇-rapid amplification of cDNA ends. The full-length cDNA had 661 bp and the sequence encoded an open reading frame of 168 amino acids. The mature protein of ZCA Includes 109 amino acid residues and the molecular weight of the protein was 12.1 kDa. The result show that the zca gene encodes a protein precursor with a signal peptlde, a mature protein, and a C-terminal cleavage amino acids sequence. Molecular modeling of ZCA Indicated that Its three-dimensional atructure strongly resembies that of the snowdrop aggiutinin. Blocks＇ analysis revealed that the deduced amino acid sequence of ZCA has three functional domains specific for agglutination and three carbohydrate binding boxes （QDNY）.

关键词： agglutinating activity insecticidal activity molecular clone sequence analysis Zephyranthes candida agglutinin.

机器学习在智能反射面辅助的通信系统中的应用综述

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北京工业大学学报 2025年第1期51卷 87-99页

作者：司鹏搏李双缘刘畅李萌北京工业大学信息学部北京100124 先进信息网络北京实验室北京100124

智能反射面(intelligent reflecting surfaces,IRS)可以通过大量低成本的无源反射元件巧妙地调整信号反射,从而动态改变无线信道,提高通信性能,目前已成为无线通信研究的焦点。然而,由于IRS的加入,整个通信系统变得更加复杂,系统的动态... 详细信息

智能反射面(intelligent reflecting surfaces,IRS)可以通过大量低成本的无源反射元件巧妙地调整信号反射,从而动态改变无线信道,提高通信性能,目前已成为无线通信研究的焦点。然而,由于IRS的加入,整个通信系统变得更加复杂,系统的动态性也更高,使通信系统面临着许多新的挑战。机器学习(machine learning,ML)具有很强的数据处理与自适应能力,能够不断适应变化的环境和需求,可以很好地应对通信系统中的许多挑战。因此,使用ML解决IRS辅助的通信系统中的问题,已经成为当前研究的重点。基于此,对ML在IRS系统中的应用进行了系统性的概述,从IRS辅助的通信系统中存在的问题入手,分别从反射因子的设计与优化、信道处理与建模、资源分配和管理、安全性增强4个方面对ML在IRS系统中的应用进行阐述和分析,并讨论了将ML应用在IRS系统中的优势及未来的发展趋势与挑战。

关键词：智能反射面(intelligent reflecting surfaces,IRS) 无线通信反射因子信道资源分配通信安全机器学习(machine learning,ML)

A Putative Calcium-Permeable Cyclic Nucleotide-Gated Channel,CNGC18,Regulates Polarized Pollen Tube Growth

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Journal of Integrative Plant Biology 2007年第8期49卷 1261-1270页

作者： fang chang National Key Laboratory of Plant Physiology and Biochemistry CAU-UCR Joint Center for Biological Sciences China Agricultural University Beijing 100094 China Center for Plant Cell Biology and Department of Botany and Plant Sciences University of California Riverside CA 92521 USA

A tip-focused Ca^2＋ gradient is tightly coupled to polarized pollen tube growth, and tip-localized influxes of extracellular Ca^2＋ are required for this process. However the molecular identity and regulation of the potential Ca^2＋ channels remains elusive. The present study has implicated CNGC18 （cyclic nucleotide-gated channel 18） in polarized pollen tube growth, because its overexpression induced wider and shorter pollen tubes. Moreover, CNGC18 overexpression induced depolarization of pollen tube growth was suppressed by lower extracellular calcium （[Ca^2＋]ex）. CNGC18-yellow fluorescence protein （YFP） was preferentially localized to the apparent post-Golgi vesicles and the plasma membrane （PM） in the apex of pollen tubes. The PM localization was affected by tip-localized ROP1 signaling. Expression of wild type ROP1 or an active form of ROP1 enhanced CNGC18-YFP localization to the apical region of the PM, whereas expression of RopGAP1 （a ROP1 deactivator） blocked the PM localization. These results support a role for PM-Iocalized CNGC18 in the regulation of polarized pollen tube growth through its potential function in the modulation of calcium influxes.

关键词： tip growth ROP GTPase RIC3 RIC4 calcium channel,

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图像去模糊处理研究

电脑知识与技术 2020年第32期16卷 189-191,194页

作者：付蕊李常芳施淑仙赵加敏保山学院信息学院云南保山678000

为减小噪音对图像的影响,结合小波阈值去噪算法和维纳滤波去噪算法两者的优势进行改进,提出一种图像去噪效果更好的方法。该方法首先对图像添加高斯白模糊,模拟图像在不同程度下的模糊情况,其次对添加了不同高斯白噪声下的图像分别进行... 详细信息

为减小噪音对图像的影响,结合小波阈值去噪算法和维纳滤波去噪算法两者的优势进行改进,提出一种图像去噪效果更好的方法。该方法首先对图像添加高斯白模糊,模拟图像在不同程度下的模糊情况,其次对添加了不同高斯白噪声下的图像分别进行小波阈值、Wiener滤波、小波阈值和Wiener滤波联合去噪,对比不同不通滤波在相同条件下的去噪效果,最后,计算出降噪之前以及降噪之后的图像信噪比、峰值信噪比。仿真结果表明,该方法的信噪比和峰值信噪比大于比单独使用Wiener滤波和单独使用小波阈值去噪,图像的还原度也较之两者要好。

关键词：小波变换小波阈值维纳滤波图像去噪图像去模糊

审慎态度和慎独行为在手术室工作中的重要性及培养

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中国医学伦理学 2011年第1期24卷 35-37页

作者：李向利汤亚娥孔德玲李小英常方丽吴和媛西安交通大学医学院第二附属医院手术室陕西西安710004 西安交通大学医学院第二附属医院中国皮肤性病学杂志编辑部陕西西安710004

对手术室护理人员来讲,审慎的工作态度和慎独行为的修养极为重要。审慎有助于增强手术室护理人员的医疗责任感,有助于提高手术室护理人员的业务素质,有助于手术室护理人员和相关手术科室的协作,应通过有效措施对手术室护理人员审慎意识... 详细信息

对手术室护理人员来讲,审慎的工作态度和慎独行为的修养极为重要。审慎有助于增强手术室护理人员的医疗责任感,有助于提高手术室护理人员的业务素质,有助于手术室护理人员和相关手术科室的协作,应通过有效措施对手术室护理人员审慎意识进行培养。慎独在手术室护理中也具有很大的重要性,热爱手术室护理工作是培养慎独修养的前提,加强三基培训提高综合素质是培养慎独意识的关键,在日常工作中严格按操作规程操作养成慎独的习惯,加强对手术室护理人员慎独意识的培养,对各类实习学生和进修生慎独意识的培养,加强节假日值班人员的慎独意识。

关键词：审慎态度慎独行为护理人员医疗责任感道德修养