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Spatial heterogeneity and compositional profiles of dissolved organic matter in farmland soils across China' Mainland

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Journal of Environmental Sciences 2024年第3期137卷 593-603页

作者： Bingjun Han liyuan Chen Kang Xiao Yang liu Dong Cao Lu Yu Yujun Li Shu Tao Wenxin liu Key Laboratory for Earth Surface Processes College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Beijing Yanshan Earth Critical Zone National Research Station College of Resources and EnvironmentUniversity of Chinese Academy of SciencesBeijing 101408China Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienceChinese Academy of SciencesBeijing 100085China

Dissolved organic matter(DOM) plays an essential role in many geochemical processes,however its complexity, chemical diversity, and molecular composition are poorly understood. Soil samples were collected from 500 vegetable fields in administrative regions of China' Mainland, of which 122 were selected for further investigation. DOM properties were characterized by three-dimensional excitation-emission matrix(3D-EEM) fuorescence spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry(FTICRMS)(field intensity is 15 Tesla). Our results indicated that the main constituents were UVA humic-like substances, humic-like substances, fulvic acid-like substances, and tyrosine-like substances. A total of 10,989 molecular formulae with a mass range of 100.04 to 799.59 Da were detected, covering the mass spectrometric information of the soil samples from 27 different regions. CHO and CHON molecules were dominant in DOM, whereas lignin, tannins,and aromatic substances served as the main components. The results of cluster analysis revealed that the soil properties in Jiangxi Province were considerably different from those in other regions. The key backgrounds of the DOM molecular characteristics in the vegetablefield soil samples across China' Mainland were provided at the molecular level, with large abundance and great variability.

关键词： Dissolved organic matter(DOM) Fourier transform ion cyclotron resonance mass(FTICR-MS) Excitation-emission matrix(EEM) Vegetable-field soils China' Mainland

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Exploration of high-speed 3.0 THz imaging with a 65 nm CMOS process

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半导体学报:英文版 2023年第10期44卷 78-85页

作者： Min liu Ziteng Cai Jian liu Nanjian Wu liyuan liu State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Faculty of Information Technology Beijing University of TechnologyBeijing 100124China

This paper describes a promising route for the exploration and development of 3.0 THz sensing and imaging with FET-based power detectors in a standard 65 nm CMOS *** on the plasma-wave theory proposed by Dyakonov and Shur,we designed high-responsivity and low-noise multiple detectors for monitoring a pulse-mode 3.0 THz quantum cascade laser(QCL).Furthermore,we present a fully integrated high-speed 32×32-pixel 3.0 THz CMOS image sensor(CIS).The full CIS measures 2.81×5.39 mm^(2) and achieves a 423 V/W responsivity(Rv)and a 5.3 nW integral noise equivalent power(NEP)at room *** experiments,we demonstrate a testing speed reaching 319 fps under continuous-wave(CW)illumina-tion of a 3.0 THz *** results indicate that our terahertz CIS has excellent potential in cost-effective and commercial THz imaging and material detection.

关键词： power detectors quantum cascade laser(QCL) CMOS image sensor(CIS) terahertz

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Depressive Symptoms and Sleep Duration as Risk Factors for Breast Cancer—China,2020

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China CDC weekly 2023年第15期5卷 333-339页

作者： liyuan liu Heling Bao Fei Wang Lixiang Yu Shu Cong Fei Zhou Yujuan Xiang Shuya Huang Chao Zheng Liwen Fang Linhong Wang Zhigang Yu Department of Breast Surgery The Second Hospital of Shandong UniversityJinan CityShandong ProvinceChina Institute of Translational Medicine of Breast Disease Prevention and Treatment Shandong UniversityJinan CityShandong ProvinceChina Institute of Medical Information Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina National Center for Chronic and Noncommunicable Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina

Summary What is already known about this topic?Psychological and lifestyle factors are known to potentially play a significant role in the development of breast ***,current evidence-based studies present controversial... 详细信息

关键词： breast Breast Cancer

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高温胁迫对真海鞘滤水、耗氧率和排氨率的影响

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水产学杂志 2024年第4期37卷 56-63页

作者：卢龙飞刘力源王振华毕炜家姜景腾肖露阳威海长青海洋科技股份有限公司山东荣成264316 寻山集团有限公司山东荣成264316 威海市海洋发展研究院山东荣成264200

将在12℃条件下暂养的一、二和三龄体质量为(23.95±9.83)g、(68.95±23.84)g和(117.99±38.42)g的真海鞘(Halocynthia roretzi)分别驯化到16℃、20℃、24℃和28℃,升温幅度为1℃·h^(-1),饲养2 d后测定滤水率、耗氧率和排氨率,统计存... 详细信息

将在12℃条件下暂养的一、二和三龄体质量为(23.95±9.83)g、(68.95±23.84)g和(117.99±38.42)g的真海鞘(Halocynthia roretzi)分别驯化到16℃、20℃、24℃和28℃,升温幅度为1℃·h^(-1),饲养2 d后测定滤水率、耗氧率和排氨率,统计存活率。12℃为对照组。从各组中随机取6只真海鞘移入装有1 L海水的烧杯中,添加至终浓度为104 cells·mL^(-1)的三角褐指藻(Phaeodactylum tricornutum),保持通气,每隔30~60 min采集水样测定滤水率、耗氧率和排氨率,研究高温对真海鞘滤水率、耗氧率和排氨率的影响,并分析耗氧率/排氨率比值(O/N)。结果表明,滤水率、耗氧率、排氨率和O/N的变化范围分别为1.33~5.51 mL·g^(-1)·h^(-1)、5.32~29.24μg·g^(-1)·h^(-1)、0.04~0.41μg·g^(-1)·h^(-1)和62.50~122.93。随温度升高,真海鞘的滤水率呈倒钟形变化,25.64℃时达最大值,耗氧率和排氨率持续升高,O/N显著下降;在20℃后呈现变缓或略有提升的趋势,表明真海鞘在20~24℃极可能存在代谢的转变点。真海鞘滤水率(FR)、耗氧率(R_(O))、排氨率(R_(N))和O/N(R_(O/N))与温度(t)拟合的相关方程分别为:FR=-0.0139t^(2)+0.7128t-4.7728,r^(2)=0.5401;R_(O)=1.0492t-6.2423,r^(2)=0.8268;R_(N)=0.0169t-0.1703,r^(2)=0.8574;R_(O/N)=-69.2940ln(t)+292.9675,r^(2)=0.8900。综上所述,合理养殖真海鞘的温度上限应在24℃左右。

关键词：真海鞘温度滤水率耗氧率排氨率 O/N

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One-year observation of the mixing states of oxygenated organics-containing single particles in Guangzhou,China

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 155-169页

作者： liyuan Mao Suxia Yang Xiaoya Cheng Sulin liu Duanying Chen Zhen Zhou Mei Li Chenglei Pei Chunlei Cheng Institute of Mass Spectrometry and Atmospheric Environment Guangdong Provincial Engineering Research Center for the On-line Source Apportionment System of Air PollutionJinan UniversityGuangzhou510632China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Guangzhou510632China Guangzhou Research Institute of Environment Protection Co. Ltd.Guangzhou510620China Guangzhou Ecological and Environmental Monitoring Center of Guangdong Province Guangzhou510030China State Key Laboratory of Marine Resource Utilization in South China Sea Hainan UniversityHaikou570228China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy SciencesXi’an710061China

Oxygenated organic molecules(OOMs)play an important role in the formation of secondary organic aerosols(SOAs),but the mixing states of OOMs are still *** study investigates the mixing states of OOM-containing single particles from the measurements taken using a single particle aerosol mass spectrometer in Guangzhou,China in ***,the particle counts of OOM particles and the mass concentration of secondary organic carbon(SOC)exhibited similar temporal trends throughout the entire *** OOM particles were consistently enriched in secondary ions,including ^(16)O^(−),^(26)CN^(−),^(46)NO_(2)^(−),^(62)NO_(3)^(−),and ^(97)HSO_(4)^(−).In contrast,the number fractions and diurnal patterns of OOM particles among the total detected particles showed similar distributions in August and October;however,the SOC ratios in fine particulate matter were quite different,suggesting that there were different mixing states of single-particle oxygenated *** addition,further classification results indicated that the OOM particles were more aged in October than August,even though the SOC ratios were higher in ***,the distribution of hydrocarbon fragments exhibited a notable decrease from January to October,emphasizing the more aged state of the organics in *** addition,the sharp increase in elemental carbon(EC)-OOM particles in the afternoon in October suggests the potential role of EC in the aging process of ***,in contrast to the bulk analysis of SOC mass concentration,the mixing states of the OOM particles provide insights into the formation process of SOAs in field studies.

关键词： Oxygenated organics Single particles Mixing state Secondary formation Photochemistry

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The Status of Organochlorine Pesticides Pollution in Hubei Section of the Yangtze River

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地学前缘 2009年第S1期16卷 81-82页

作者： Chen liu,liyuan Guo School of the Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China.

The Organochlorine Pesticides(OCPs),such as hexachlorocyclohexane(HCH)and dichlorodiphenyltrichloro ethane(DDT),are well known as typical persistent organic pollutions(POPs).They were worldwide used several decades ago,even today in some *** the water resource is very important in natural environments and essential to agriculture,the pollution of OCPs in water has emerged as worldwide environmental problem. Wuhan section of the Yangtze River is the drinking water source of Wuhan area in Hubei *** addition,Hubei province is an important production base of grain,cotton,oil and *** the rapid development of industry and mass-use of OCPs

关键词： organochlorine pesticides Yangtze River water residues

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Research on the Efficiency Evaluation for the Board Based on GT-AHP Method

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Journal of Systems Science and Information 2006年第4期4卷 783-790页

作者： Ligen Yao Tao liu liyuan Ren Lei liu School of Economics and Management Hebei University of Engineering Handan 056038 China

The board of directors is the core of corporate governance mechanism. In order to enhance the operation efficiency of the board, and to further reduce the agency cost, effective appraisal of the efficiency of the board becomes urgent. This paper firstly uses graph transformation and matrix algorithm to analyze the performance evaluation factors of the board and establishes the ordered hierarchy structure of the appraisal indexes. Then, it calculates the index weights with the AHP method. Next, it sets up the efficiency appraisal index system of the board. At last, the paper gives an empirical analysis with an example.

关键词： AHP board efficiency efficiency evaluation GT

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不同除草方式对苹果苗木生长的影响

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陕西农业科学 2024年第4期70卷 109-114页

作者：刘丽媛王淼马娟娟张东吴婉莉丁亦非李高潮西北农林科技大学园艺学院陕西杨凌712100 咸阳市农业科学研究院陕西咸阳712034

苗圃地极易滋生杂草,除草不当会阻碍苗木的正常生长发育,选择适宜的除草方式尤为重要,以苗木‘宫藤富士/G935’为试验材料,研究不同除草方式对苹果苗木生长的影响,为苗圃地绿色经济发展提供理论依据。结果表明:在苗木株高方面,地布防草... 详细信息

苗圃地极易滋生杂草,除草不当会阻碍苗木的正常生长发育,选择适宜的除草方式尤为重要,以苗木‘宫藤富士/G935’为试验材料,研究不同除草方式对苹果苗木生长的影响,为苗圃地绿色经济发展提供理论依据。结果表明:在苗木株高方面,地布防草显著高于除草剂除草与人工除草为166.07 cm。不同除草方式对侧枝也有影响,表现为地布防草与除草剂除草显著提高了长枝的占比,分别为56.51%与52.11%,而人工除草的苗木以中枝为主,占52.11%。地布防草有效提高了有效分枝粗度与分枝角度,分别达到了3.96 mm与62.86度。此外,地布防草较人工除草每年每667 m^(2)节约除草成本约为150元。总之,地布防草不仅提高了苹果苗木的生长质量,还能节约成本,可在苗木繁育中大力推广应用。

关键词：苹果除草方式苗木生长成本分析

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电场调控增强型背照式单光子雪崩二极管

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集成电路与嵌入式系统 2024年第10期24卷 1-8页

作者：李聪王哲杨旭田娜冯鹏窦润江于双铭刘剑吴南健李传波刘力源中央民族大学理学院北京100081 中国科学院半导体研究所半导体超晶格国家重点实验室北京100083 中国科学院大学材料科学与光电技术学院北京100049 中国科学院大学电子电气与通信工程学院北京100049

本研究利用搭建的仿真设计平台开发了一款电场调控增强型背照式单光子雪崩二极管(SPAD)器件,通过调控SPAD雪崩区电场,进一步提升了背照式器件的光子探测效率,降低了暗计数率。仿真结果表明,本研究设计的SPAD在水平和垂直电场的协同作用... 详细信息

本研究利用搭建的仿真设计平台开发了一款电场调控增强型背照式单光子雪崩二极管(SPAD)器件,通过调控SPAD雪崩区电场,进一步提升了背照式器件的光子探测效率,降低了暗计数率。仿真结果表明,本研究设计的SPAD在水平和垂直电场的协同作用下,有效提高了电子倍增效率,峰值探测效率达到50.1%,在过偏压为3 V时,暗计数率降低至764 Hz。本文对比分析了不同耗尽层厚度和P Well半径对电场调控增强型背照式SPAD器件性能的影响,并确定了最优结构尺寸。研究结果为基于SPAD的高精度光电探测应用提供了新的技术途径,为SPAD器件在科学研究和工业应用中的进一步发展奠定了基础。

关键词：单光子雪崩二极管背照式光子探测效率暗计数率电场调控器件仿真

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Relationship with spatial memory in diabetic rats and protein kinase Cγ,caveolin-1 in the hippocampus and neuroprotective effect of catalpol

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Chinese Medical Journal 2014年第5期127卷 916-923页

作者： Zhou Haicheng liu Jing Ren liyuan liu Wei Xing Qian Men Lili Song Guirong Du Jianling Department of Endocrinology First Affiliated Hospital of Dalian Medical University Dalian Liaoning 116011 China

Background The mechanisms underlying diabetic encephalopathy are largely unknown,and no effective treatments are *** has received much attention due to its numerous biological effects,especially in neuroprotective *** aim of this study was to investigate the effects of catalpol on cognitive functions in diabetic rats and the underlying *** A rat model of diabetes was established by streptozotocin injection,followed by intraperitoneal infusion of catalpol after 10 *** weeks later,the Morris water maze was used to test the spatial learning *** staining was performed to evaluate the morphological changes in the *** of protein kinase Cy （PKCy） and caveolin-1 （Cav-1） in the hippocampus were assessed by reverse transcription PCR and Western *** of anti-oxidative enzymes such as glutathione （GSH）,superoxide dismutase （SOD） and catalase （CAT） and levels of malonaldehyde （MDA） were measured using commercial *** Significant hippocampal neuronal injury was observed in rats with streptozotocin-induced ***,cognitive dysfunction was associated with markedly increased oxidative stress in the *** treatment significantly attenuated cognitive deficits,neuronal damage,and oxidative stress in the brain of diabetic *** analyses showed that catalpol reversed the down-regulation of PKCγ and Cav-1 expression in the diabetic *** Spatial memory in diabetic rats is associated with the expression of PKCy and *** treatment markedly attenuated oxidative stress,reversed the alteration of PKCy,Cav-1 and spatial memory deficits.

关键词： catalpol diabetic encephalopathy protein kinase Cγ caveolin-1

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