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Iodine enrichment in the groundwater in South China and its hydrogeochemical control

Journal of Environmental Sciences 2024年第8期142卷 226-235页

作者： Fengping Zhou Qianting Xu Yuyun Chen weihua zhang Rongliang Qiu Guangdong Provincial Key Laboratory of Environmental Pollution and Remediation Technology Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil RemediationSchool of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Shenzhen Research Institute Sun Yat-sen UniversityShenzhen 518057China Guangdong Provincial Key Laboratory of Agricultural&Rural Pollution Abatement and Environmental Safety School of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China

In North China,iodine-rich groundwater has been extensively studied,but few in South *** study aimed to investigate the characteristics of iodine-rich groundwater in South China and identify potential contamination *** results revealed that the average concentration of iodine in groundwater was 890μg/L,with a maximumconcentration of 6350μg/L,exceeding the permitted levels recommended by the World Health Organization(5–300μg/L).Notably,the enrichment of iodide occurred in acidic conditions(pH=6.6)and a relatively low Eh environment(Eh=198.4 mV).Pearson correlation and cluster analyses suggested that the enrichment of iodide could be attributed to the intensified redox process involving Mn(II),iodine(I_(2)),or iodate(IO_(3)^(−))in the *** strong affinity between Mn(II)and I_(2)/IO_(3)^(−)facilitated their interaction,resulting in the formation and mobilization of I^(−)from the soil to the *** experiments further confirmed that reducing substances(such as sodium sulfides,ascorbic acids,and fulvic acids)in the soil with low dissolved oxygen(DO)levels(3.8 mg/L)promoted the oxidation of I^(−)into I_(2)or IO_(3)^(−),leading to its *** research provides new insights into the characteristics and mechanisms of I^(−)enrichment in groundwater in South China,and emphasizes the significance of the redox reactions involving Mn(II)and I_(2)/IO_(3)^(−),as well as the influence of soil properties in regulating the occurrence and transportation of iodine species within groundwater systems.

关键词： Iodine enrichment Acid environment Groundwater South China Manganese

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The effect of thermal treatment on the transformation and transportation of arsenic and cadmium in soil

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Journal of Environmental Sciences 2024年第11期145卷 205-215页

作者： Fengping Zhou Meina Guo Nan Zhao Qianting Xu Tuokun Zhao weihua zhang Rongliang Qiu Guangdong Provincial Key Laboratory of Environmental Pollution and Remediation Technology Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil RemediationSchool of Environmental Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Shenzhen Research Institute Sun Yat-sen UniversityShenzhen 518057China National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China Guangdong Provincial Key Laboratory of Agricultural&Rural Pollution Abatement and Environmental Safety School of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China

Thermal treatment can effectively decontaminate soils but alter their *** research mainly focused on volatile organic compounds andmetals,***,neglecting nonvolatile metal(loid)*** study aimed to investigate Cd and As transformation during aerobic and anaerobic *** results showed that both aerobic and anaerobic calcination increased soil pH by reducing soil organic matter(SOM)content,which also influenced the cation exchange capacity(CEC)and the leaching behavior of Cd and As in the *** total concentrations of Cd and As in the calcined soils varied depending on the calcination temperature and *** the aerobic calcination temperature exceeded 700℃,Cd volatilized as CdCl_(2),while anaerobic calcination at relatively low temperatures(600℃)involved reductive reactions,resulting in the formation of metallic Cd with a lower boiling ***,As volatilized at 800℃aerobically and 600℃*** formation of As-based minerals,particularly Ca3(AsO4)2,hindered its gasification,whereas anaerobic calcination promoted volatilization efficiency through the generation of C-As(III)based gaseous components with lower boiling *** trends were observed in the TCLP-extractable Cd and As contents of the calcined *** 70%of TCLP-extractable Cd contents were suppressed after thermal treatment,attributed to the elevated pH and reduced CEC of the soil,as well as ***,TCLP-extractable As contents increased with elevated temperatures,likely due to the desorption of AsO43−and re-adsorption of gaseous As2O3 during *** findings have implications for assessing the environmental impact of thermal treatment and provide insights for remediation strategies concerning Cd and As-contaminated soils.

关键词： Thermal treatment Soil Cadmium Arsenic Transformation

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张卫华运用尺胫针疗法结合减压松动手技治疗神经根型颈椎病经验撷要

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中国针灸 2024年第7期44卷 833-837页

作者：张朴张卫华王卫刚李昂裴慧陕西中医药大学附属医院针灸科咸阳712000 陕西中医药大学第二附属医院名医馆咸阳712046

介绍张卫华教授运用尺胫针疗法结合减压松动手技治疗神经根型颈椎病的经验。张卫华教授采用“二摸三查两阅”法对疾病的病位、分期、程度进行精确诊断,根据疾病的性质认为神经根型颈椎病当从3期论治,提出“以筋为纲,以经为要,以气血为基... 详细信息

介绍张卫华教授运用尺胫针疗法结合减压松动手技治疗神经根型颈椎病的经验。张卫华教授采用“二摸三查两阅”法对疾病的病位、分期、程度进行精确诊断,根据疾病的性质认为神经根型颈椎病当从3期论治,提出“以筋为纲,以经为要,以气血为基,筋骨并调”的学术思想,运用尺胫针疗法结合减压松动手技进行治疗。尺胫针选取太阳、少阳经尺部之区带的下1/3皮部(带状)范围进针;减压松动手技分为放松颈项、减压松动(包括定位旋转扳法、上抬后顶法、仰侧扳法)、镇痛理筋3步,并配合镇痛理筋手法加强疗效。

关键词：神经根型颈椎病尺胫针减压松动手技名医经验张卫华

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Wafer-scale carbon-based CMOS PDK compatible with siliconbased VLSI design flow

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Nano Research 2024年第8期17卷 7557-7566页

作者： Minghui Yin Haitao Xu Yunxia You Ningfei Gao weihua zhang Hongwei Liu Huanhuan Zhou Chen Wang Lian-Mao Peng Zhiqiang Li Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China State Key Lab of Fabrication Technologies for Integrated Circuits Beijing 100029China Beijing Hua Tan Yuan Xin Electronics Technology Co. Ltd.Beijing 101399China Institute of Carbon-based Thin Film Electronics Peking UniversityShanxi 030012China Key Laboratory for the Physics and Chemistry of Nanodevices and Center for Carbon-based Electronics School of ElectronicsPeking UniversityBeijing 100871China

Carbon nanotube field-effect transistors(CNTFETs)are increasingly recognized as a viable option for creating high-performance,low-power,and densely integrated circuits(ICs).Advancements in carbon-based electronics,encompassing materials and device technology,have enabled the fabrication of circuits with over 1000 gates,marking carbon-based integrated circuit design as a burgeoning field of research.A critical challenge in the realm of carbon-based very-large-scale integration(VLSI)is the lack of suitable automated design methodologies and infrastructure *** this study,we present the development of a waferscale 3μm carbon-based complementary metal-oxide-semiconductor(CMOS)process design kit(PDK)(3μm-CNTFETs-PDK)compatible with silicon-based Electronic Design Automation(EDA)tools and VLSI circuit design *** proposed 3μm-CNTFETs-PDK features a contacted gate pitch(CGP)of 21μm,a gate density of 128 gates/mm^(2),and a transistor density of 554 transistors/mm^(2),with an intrinsic gate delay around 134 *** of the 3μm-CNTFETs-PDK was achieved through the successful design and tape-out of 153 standard cells and 333-stage ring oscillator *** the carbon-based PDK and a silicon-based design platform,we successfully implemented a complete 64-bit static random-access memory(SRAM)circuit system for the first time,which exhibited timing,power,and area characteristics of clock@10 kHz,122.1μW,3795μm×2810μ*** research confirms that carbon-based IC design can be compatible with existing EDA tools and silicon-based VLSI design flow,thereby laying the groundwork for future carbon-based VLSI advancements.

关键词： carbon nanotube field-effect transistors(CNTFETs) complementary metal-oxide-semiconductor(CMOS) process design kit(PDK) wafer-scale very-large-scale integration(VLSI)

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Theory and practice for assessing structural integrity and dynamical integrity of high-speed trains

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Railway Sciences 2024年第2期3卷 113-127页

作者： weihua zhang Yuanchen Zeng Dongli Song Zhiwei Wang State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengduChina School of Mechanical Engineering Southwest Jiaotong UniversityChengduChina

Purpose–The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle *** paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and *** key principles and approacheswill be proposed,and their applications to high-speed trains in Chinawill be ***/methodology/approach–First,the structural integrity and dynamical integrity of high-speed trains are defined,and their relationship is ***,the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are ***,the principles and approaches for assessing the dynamical integrity of highspeed trains are presented and a novel operational assessment method is further ***–Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle *** assessing the structural integrity of structural components,an open-loop analysis considering both normal and abnormal vehicle conditions is *** assessing the structural integrity of dynamical components,a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is *** analysis of vehicle system dynamics should follow the principles of complete objects,conditions and ***,experimental and operational approaches should be combined to achieve effective ***/value–The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects,better lifespan management of train components and better maintenance decision-making for high-speed trains.

关键词： Structural integrity Dynamical integrity Vehicle system dynamics High-speed trains Bogie Integrity assessment Fatigue

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基于混合加点Kriging代理模型的高速列车头型气动多目标优化

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西南交通大学学报 2024年第1期59卷 46-53页

作者：戴志远李田张卫华张继业西南交通大学轨道交通运载系统全国重点实验室四川成都610031

在高速列车多目标气动优化设计中,结合传统加点准则建立的代理模型在初始抽样样本点较少时寻优效率较低.为提高优化效率,本文融合改善期望加点准则(EIC)及Pareto前沿解加点准则(PIC),提出混合加点准则(HIC)方法,并基于HIC方法建立Krigin... 详细信息

在高速列车多目标气动优化设计中,结合传统加点准则建立的代理模型在初始抽样样本点较少时寻优效率较低.为提高优化效率,本文融合改善期望加点准则(EIC)及Pareto前沿解加点准则(PIC),提出混合加点准则(HIC)方法,并基于HIC方法建立Kriging代理模型,以高速列车头车气动阻力、尾车气动阻力及尾车气动升力最小为优化目标,开展高速列车头型多目标气动优化研究;并以Branin单目标测试函数和Poloni多目标测试函数为例,对比分析EIC、PIC和HIC 3种代理模型的收敛速度.结果表明:单目标优化中,相比于EIC和HIC代理模型,HIC代理模型的寻优效率提高50.0%;多目标优化中,与PIC代理模型相比,HIC代理模型的效率提高62.5%;采用HIC代理模型开展头型多目标气动优化得到的最优解模型与原始模型相比,高速列车头车气动阻力、尾车气动阻力和尾车气动升力分别降低1.6%、1.7%和3.0%;最优解模型的鼻尖高度、车钩区域高度及司机室视窗高度都有所降低,2条横向轮廓线内缩.

关键词：代理模型混合加点准则(HIC) 高速列车气动优化

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基于加权联合提升包络谱的轴箱轴承故障诊断

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西南交通大学学报 2024年第1期59卷 142-150页

作者：程尧陈丙炎张卫华李夫忠西南交通大学轨道交通运载系统全国重点实验室四川成都610031 成都运达科技股份有限公司四川成都610097

为解决列车轴箱轴承微弱故障特征在宽频带上难以提取的问题,基于轴承故障信号的二阶循环平稳特性,提出了一种利用加权联合提升包络谱进行故障诊断的方法.首先,利用谱相干算法将振动信号分解到由频谱频率和循环频率构成的双频域,实现振... 详细信息

为解决列车轴箱轴承微弱故障特征在宽频带上难以提取的问题,基于轴承故障信号的二阶循环平稳特性,提出了一种利用加权联合提升包络谱进行故障诊断的方法.首先,利用谱相干算法将振动信号分解到由频谱频率和循环频率构成的双频域,实现振动信号在全频带内的精细化解调,并基于谱相干的局部特征识别轴承候选故障频率;接着,利用1/3二叉树滤波器将频谱频率分割为不同中心频率和带宽的窄带,在窄带内沿着频谱频率对谱相干的模进行积分,得到窄带提升包络谱;然后,以候选故障频率在窄带提升包络谱中的能量占比为诊断性指标,在每一分解层上构造联合提升包络谱;最后,对不同分解层的联合提升包络谱进行加权平均,得到轴承振动信号的加权联合提升包络谱.轨道车辆轴箱轴承台架试验信号的研究结果表明:所提方法的优势在于能充分整合分布于不同窄带内的轴承故障信息,且不依赖于名义故障周期信息;和现有方法相比,能更有效地揭示轴承故障特征频率及其谐波特征,在提取和识别轴箱轴承微弱故障方面具有一定优势.

关键词：轴箱轴承故障诊断多频带故障特征提取加权联合提升包络谱谱相干

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张卫华应用“开窍利咽四步针法”治疗脑卒中后吞咽障碍

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针灸临床杂志 2024年第2期40卷 98-101页

作者：马利波王健曹雪张卫华陕西中医药大学陕西咸阳712046 陕西中医药大学第二附属医院陕西咸阳712000 咸阳市中心医院陕西咸阳712000

总结张卫华教授应用“开窍利咽四步针法”治疗脑卒中后吞咽障碍临床经验。开窍利咽四步针法即将头针治疗与局部取穴相结合,针对脑卒中后吞咽障碍的临床特点,融现代解剖理论与经络理论为一体,以病灶侧头针区、咽颈部以及舌下络脉为治疗部... 详细信息

总结张卫华教授应用“开窍利咽四步针法”治疗脑卒中后吞咽障碍临床经验。开窍利咽四步针法即将头针治疗与局部取穴相结合,针对脑卒中后吞咽障碍的临床特点,融现代解剖理论与经络理论为一体,以病灶侧头针区、咽颈部以及舌下络脉为治疗部位,应用头针连刺法、雀啄点刺法、苍龙寻珠法和刺络放血法等特殊手法,共奏醒脑开窍、通关利咽之效,临床屡获良效。

关键词：脑卒中吞咽障碍开窍利咽四步针法张卫华

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演化排列优化拉丁超立方设计方法

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国防科技大学学报 2024年第3期46卷 150-157页

作者：李国盛张锡文谦杨家伟张为华武泽平国防科技大学空天科学学院湖南长沙410073

拉丁超立方设计是最常用的计算机试验设计方法之一,针对现有拉丁超立方设计方法采样一次性且难以兼顾设计的空间均匀性和计算效率的问题,提出了一种演化排列拉丁超立方试验设计方法。通过对小样本设计的演化、排列信息继承和扩充等操作... 详细信息

拉丁超立方设计是最常用的计算机试验设计方法之一,针对现有拉丁超立方设计方法采样一次性且难以兼顾设计的空间均匀性和计算效率的问题,提出了一种演化排列拉丁超立方试验设计方法。通过对小样本设计的演化、排列信息继承和扩充等操作,以较小的计算量实现了样本的扩充与优化。此外,所提方法可以兼顾现有样本和新增采样点之间的关系,实现样本的序列扩充,这在实际近似建模过程中十分方便。通过多组数值试验,验证了本文方法在空间均匀性和计算效率等方面的优越性。

关键词：计算机试验设计优化拉丁方设计排列信息继承空间均匀性

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不同海拔高度环境下高速列车气动特性研究

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机械工程学报 2024年第16期60卷 291-305页

作者：戴志远李田张卫华张继业西南交通大学轨道交通运载系统全国重点实验室成都610031

高海拔地区气候环境相对恶劣,海拔越高,空气压力、温度及密度越低。因此,研究高速列车在高海拔运行环境下的气动特性对列车运行安全性及高海拔地区铁路建设具有重要意义。以某型号高速列车为研究对象,对明线单车、明线会车及隧道通过运... 详细信息

高海拔地区气候环境相对恶劣,海拔越高,空气压力、温度及密度越低。因此,研究高速列车在高海拔运行环境下的气动特性对列车运行安全性及高海拔地区铁路建设具有重要意义。以某型号高速列车为研究对象,对明线单车、明线会车及隧道通过运行工况进行气动数值模拟计算,研究不同海拔高度下列车的气动载荷及交变压力特性。研究结果表明,明线单车运行高速列车的气动阻力及气动升力都随海拔的增加而降低,但气动阻力系数及气动升力系数基本不随海拔的增加而改变,气动阻力系数中的压差阻力系数随海拔的增加而减小,黏性阻力系数随海拔的增加而增大。不同海拔高度下列车交会压力波及隧道压力波变化规律一致,但压力波幅值随海拔高度的增加而减小;列车交会压力波峰值和隧道通过的列车压力波、出口微气压波都与海拔高度呈现较强的相关性。此外,海拔高度增加带来的温度变化使压力波的传播速度降低,导致不同海拔高度下隧道压力波及出口微气压波出现滞后现象。

关键词：高速列车高原海拔高度气动特性数值模拟

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