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Soil properties and not plant factors affect both abundant and rare microbial taxa after thinning in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu

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Journal of Forestry Research 2024年第2期35卷 81-94页

作者： Wanxia Peng Tongqing Song Hu Du Feng Wang fuping zeng Yang Wang Shulin Chen Yinzhu Chen Key Laboratory of Agro‑Ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125People’s Republic of China Guangxi Industrial Technology Research Institute for Karst Desertification Control Nanning 530001People’s Republic of China Huanjiang Observation and Research Station for Karst Ecosystems Institute of Subtropical AgricultureChinese Academy of SciencesChangsha 410125People’s Republic of China Hubei Ecology Polytechnic College Wuhan 430200People’s Republic of China Hubei Tongshan Damushan State Forest Farm Tongshan 437652People’s Republic of China

Thinning is an effective management step for sustainable forest development,yet less attention is paid to the restoration of soil microbiota after thinning.In this study,both abundant and rare soil microbial communities(i.e.,bacterial,fungal),were evaluated under various thinning treatments in a mixed stand of Cunninghamia lanceolata and Sassafras tzumu using Mi Seq sequencing.Thinning did not significantly change either abundant or rare bacterial and fungal community composition,but affected their alpha diversity.The Shannon–Wiener indexes of rare fungal taxa under medium thinning were significantly lower than in the light thinning(P<0.05 level).Xanthobacteraceae dominated the abundant bacterial taxa,and Saitozyma and Mortierlla the abundant fungal taxa.The most common rare bacterial taxa varied;there was no prevalent rare fungal taxa under different thinnings.In addition,soil available nitrogen,total phosphorus,and p H had significant effects on rare bacterial taxa.Nutrients,especially available phosphorus,but not nitrogen,affected abundant and rare soil fungi.The results indicate that soil properties rather than plant factors affect abundant and rare microbial communities in soils of mixed stands.Thinning,through mediating soil properties,influences both abundant and rare bacterial and fungal communities in the mixed C.lanceolata and S.tzumu stand.

关键词： Diversity Abundant taxa Rare taxa Thinning Mixed stand

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SF_(6) decomposition behaviour under partial discharge of typical insulation defects in gas-solid insulated valve-side bushing of converter transformer

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High Voltage 2023年第4期8卷 690-697页

作者： Hongtu Cheng fuping zeng Bowen Tang Haotian Li Ju Tang Zujian Huang Xianzong Chao School of Electrical Engineering and Automation Wuhan UniversityWuhanChina Hubei Key Laboratory of Power Equipment&System Security for Integrated Energy Resources WuhanChina School of Electrical and Electronic Engineering Hubei University of TechnologyWuhanChina

In this paper we investigated SF_(6) decomposition behaviour of typical insulation defects in gas-solid insulated converter transformer valve-side bushing under partial discharge(PD).Additionally,we compared the results with that of gas insulated switchgear(GIS).The results indicated that SF_(6) decomposition behaviour varies with the insulation defects type.For metal protrusion defects,the proportion ranking of CO_(2) and SO_(2) can be related to whether the needle tip is wrapped with epoxy resin-impregnated paper(ERIP).The proportion of carbon-containing products is much higher under contamination defect than under other defects.Moreover,the proportion of carbon-containing components is higher under flashover condition than under PD condition and is accompanied by the appearance of H2S and CS_(2).However,the yield of SO_(2)F_(2) is always low.Compared to negative DC voltages,positive DC voltages have a higher proportion of carboncontaining components,mainly in the form of more CO_(2) and less SOF_(2).Compared to the PD decomposition behaviour of typical insulation defects in GIS,when PD involves ERIP,the proportion of carbon-containing products,especially CO_(2),is significant higher,while the proportion of sulphur containing products,especially SO_(2)F_(2),is lower.

关键词： behaviour insulation solid

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Environmental and spatial contributions to tree community assembly across life stages and scales in evergreen-deciduous broadleaf karst forests,southwest China

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林业研究:英文版 2023年第5期34卷 1323-1331页

作者： Liang Su Hu Du fuping zeng Wanxia Peng Hua Wang Kelin Wang Menzhen Lu Tongqing Song Key Laboratory of Agro-Ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academic of SciencesChangshaPeople’s Republic of China Guangxi Key Laboratory of Karst Ecological Processes and Services Huanjiang Observation and Research Station of Karst EcosystemChinese Academic of SciencesHuanjiangPeople’s Republic of China College of Resources and Environment Hunan Agricultural UniversityChangshaPeople’s Republic of China

Spatial and environmental processes are two ecological processes that have attracted considerable attention in plant community assembly,depending on sampling scale and life history.However,the processes that determine community assembly have not been studied in the karst region of southwest China.In this study,a 25-ha(500 m×500 m)monitoring plot within the subtropical climax forest in the karst region was established and canonical correspondence analysis was used to reveal the effects of topography and soil on the spatial patterns of tree community assembly.Our study suggests that spatial processes dominate species composition and the combined effects of spatial and environmental processes play an important role.Overall interpretation rate increases with enlarging the sampling scale.However,the pattern of variation partitioning was similar in different life stages.Environmental variables significantly affected species composition at different sampling sizes and life histories and had a higher interpretation rate of species composition on larger s ampling sizes.Topographic wetness index was the most important variable to explain species composition of the environmental variables.These results suggest that it is necessary to consider the relative importance of environmental and spatial factors on community assembly to better understand,conserve,and manage subtropical karst forests.

关键词： Species composition Spatial distribution Variation partitioning Community assembly Karst ecosystems

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A low-cost and high-performance self-trigger method for high-voltage transient measurement

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High Voltage 2023年第2期8卷 412-420页

作者： Hao Liu Guoming Ma Weiqi Qin Wei Wang Houxian Du Lei Wang Shicong Zhai fuping zeng Weixing Han State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijingP.R.China China Electric Power Research Institute WuhanHubei ProvinceChina School of Electrical Engineering and Automation Wuhan UniversityWuhanChina

Stable triggering of acquisition devices is critical to accurately measure electromagnetic transients,especially for very fast transient overvoltages(VFTOs).A highly stable and lowcos t self-trigger method for transient measurement is proposed.An integrated low-voltage arm module was developed to synchronously realise the triggering and VFTO measurement.The trigger branch was developed using a high-pass filter.This component obtained the high-frequency component of the VFTO to trigger the oscilloscope.The trigger branch was integrated with the measurement branch through an impedance converter.An attenuator was implemented before the impedance converter to avoid overvoltage damage to the chip.The circuit parameters of the attenuator were optimised to alleviate the disturbance of the measurement branch.The calibration results demonstrated that the±1 dB bandwidth of the measurement branch in this system ranged from 11.8 Hz to 105 MHz.The low cutoff frequency of the trigger branch was 710 Hz.The VFTO waveforms generated by the operation of a disconnector in a real 252 kV gas insulated switchgear were measured using the proposed system.The test results verified that the self-trigger measurement system can provide stable trigger signals and accurately measure the VFTO waveforms.

关键词： transient branch impedance

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补阳还五汤治疗脑梗死临床观察

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中国中医药现代远程教育 2024年第12期22卷 60-62页

作者：曾福平江西省乐平天湖医院中医康复科江西乐平333300

目的探究补阳还五汤加减治疗对脑梗死患者中医证候及血清促血管生成素Ⅱ(Ang-Ⅱ)、血管内皮生长因子(VEGF)、基质金属蛋白酶-2(MMP-2)、超敏C反应蛋白(hs-CRP)的影响。方法采用随机数字表法将2019年7月—2022年8月江西省乐平天湖医院收... 详细信息

目的探究补阳还五汤加减治疗对脑梗死患者中医证候及血清促血管生成素Ⅱ(Ang-Ⅱ)、血管内皮生长因子(VEGF)、基质金属蛋白酶-2(MMP-2)、超敏C反应蛋白(hs-CRP)的影响。方法采用随机数字表法将2019年7月—2022年8月江西省乐平天湖医院收治的脑梗死患者70例分为两组,各35例。对照组行西医治疗,研究组在其基础上联合补阳还五汤加减治疗,均治疗21 d。对比两组临床疗效、中医证候积分及血清学指标。结果研究组治疗总有效率为94.29%(33/35),高于对照组的71.43%(25/35);治疗后,研究组主证及次证积分均低于对照组,MMP-2、hs-CRP水平均低于对照组,Ang-Ⅱ、VEGF水平高于对照组,差异均有统计学意义(P<0.05)。结论脑梗死患者应用补阳还五汤加减治疗,能够有效改善各临床症状,减轻机体炎症反应,促进脑缺血半暗带内血管生成,对改善预后意义重大,值得推广应用。

关键词：中风脑梗死补阳还五汤中医药疗法

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SF_(6)decomposition and insulation condition monitoring of GIE:A review

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High Voltage 2021年第6期6卷 955-966页

作者： fuping zeng Haotian Li Hongtu Cheng Ju Tang Yilu Liu School of Electrical Engineering and Automation Wuhan UniversityWuhanChina Department of Electrical Engineering and Computer Science USA Oak Ridge National Laboratory KnoxvilleTennesseeUSA

The statistics of the Conference International des Grands Reseaux Electriques(CIGRE)indicate that the operational reliability of SF6 gas‐insulated equipment(GIE)is very high;however,the failure rate of the GIE in operation is much higher than that of the IEC standard,and the fault occurs frequently in the GIE at a high voltage level.The reason is due to the complex and strong on‐site electromagnetic interference environment and fully enclosed structure of GIE.The key method and technology for effective on‐line monitoring and fault diagnosis of GIE are still lacking.Given the partial strong electromagnetic energy and high temperature induced by early latent insulation faults in the equipment,SF6 gas insulation presents different degrees of decomposition.The decomposition products mainly include SO_(2)F_(2),SOF_(2),SO_(2),HF,and H2S.The decomposition characteristics of SF6 are closely related to the property of insulation faults.At present,this area is attracting attention from the power industry and research institutes.This study summarises the current research on SF_(6)decomposition component analysis(DCA).The content mainly includes the latest progress of SF_(6)decomposition characteristics and mechanism under fault conditions,and fault diagnosis methods based on decomposition components.

关键词： insulation fault diagnosis

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Ag表面对SF_(6)初级分解产物氧化反应的影响作用研究

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电工技术学报 2024年第9期39卷 2841-2850页

作者：李昊天曾福平颜伊鸣朱可馨姚强唐炬武汉大学电气与自动化学院武汉430072 国网重庆市电力公司电力科学研究院重庆401123

运行经验显示SF_(6)在气体绝缘开关设备(GIS)中的热稳定性低于预期,GIS内部的金属表面可能对SF_(6)初级分解与次级反应具有显著的影响作用,但作用机理尚不明晰。该文基于密度泛函理论获得了O_(2)在Ag表面的解离-吸附构型,并建立了低氟... 详细信息

运行经验显示SF_(6)在气体绝缘开关设备(GIS)中的热稳定性低于预期,GIS内部的金属表面可能对SF_(6)初级分解与次级反应具有显著的影响作用,但作用机理尚不明晰。该文基于密度泛函理论获得了O_(2)在Ag表面的解离-吸附构型,并建立了低氟硫化物与Ag表面O原子的反应模型,初步揭示了GIS过热故障状态下SF_(6)初级分解产物在Ag表面的氧化反应机理;基于过渡态理论和反应动力学理论,计算获取了界面反应的能垒和反应速率常数,并与气相反应对比,分别确定了三种低氟硫化物的氧化反应路径及其主要场所,并分析了Ag表面对反应的促进/抑制作用机制。结果显示,Ag表面可显著促进SOF_(4)与SOF_(3)的产生,但不利于SF2的表面氧化反应。

关键词：气体绝缘开关设备六氟化硫过热分解银表面氧化反应

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综合物探方法在碎屑岩地区找水中的应用——以云南宣威大路边村为例

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中国岩溶 2024年第2期43卷 432-440页

作者：郑智杰曾洁甘伏平陈吉礼卢秀华中国地质科学院岩溶地质研究所/自然资源部、广西岩溶动力学重点实验室/联合国教科文组织国际岩溶研究中心广西桂林541004 合肥工业大学安徽合肥230009 广西平果喀斯特生态系统国家野外科学观测研究站广西平果531406 广西壮族自治区三〇七核地质大队广西贵港537100

为探索地球物理方法在碎屑地区找水应用的有效性,文章以云南宣威大路边村为研究对象,选取高密度电阻率法、联合剖面法、音频大地电磁法对碎屑岩层进行找水研究。结果表明:三叠系上统飞仙关组(T1f)碎屑岩富水性中等,含水性较均匀;受地面... 详细信息

为探索地球物理方法在碎屑地区找水应用的有效性,文章以云南宣威大路边村为研究对象,选取高密度电阻率法、联合剖面法、音频大地电磁法对碎屑岩层进行找水研究。结果表明:三叠系上统飞仙关组(T1f)碎屑岩富水性中等,含水性较均匀;受地面场地狭窄限制,高密度电法及联合剖面法测线长度有限,探测深度较浅,受碎屑岩电阻率小的影响,其找水应用效果不佳,在可探测的深度范围内较难识别基岩裂隙等找水有效异常,需结合其他物探方法甄别异常;音频大地电磁法找水应用效果相对较好,具有较高的横向分辨率,可有效识别碎屑岩中的断裂破碎带及构造裂隙带,表现为相对低阻异常特征;视电阻率单支测深曲线能有效分辨不同深度的岩土层结构,具有较高的纵向分辨率,对裂隙破碎带有较好指示意义。在地面场地较为狭窄的碎屑岩地区开展找水工作,音频大地电磁法结合视电阻单支测深曲线能取得较好效果,以音频大地电磁法确定碎屑岩地区中的裂隙发育带位置,以视电阻单支测深曲线确定裂隙发育带的深度。

关键词：高密度电阻率法联合剖面法音频大地电磁法视电阻率测深曲线碎屑岩找水

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Intelligent perception of power grid condition

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High Voltage 2021年第6期6卷 923-923页

作者： Ju Tang fuping zeng School of Electrical Engineering and Automation Wuhan UniversityWuhanChina

In face of increasingly severe challenges in energy develop-ment,a secure,stable,green,and sustainable Energy Internet has become a development tendency,as a major technological innovation that promotes the transformation of the world's power and energy systems.The essence of Energy Internet is the deep integration of energy flow and information flow,which is the in‐depth perception and control of the energy network situation using advanced information technology.Electric energy equipment and its grid structure are the core of Energy Internet.Energy Internet needs to integrate all the information that can be collected to perceive the situation of power equipment and the entire grid deeply and accurately,so as to prevent sudden power outages caused by equipment failure or system instability,and to improve the reliability and economy of the entire Energy Internet.

关键词： power perception condition

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喀斯特常绿落叶阔叶混交林凋落叶养分含量时空分布特征

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生态学报 2024年第2期44卷 733-744页

作者：淦江黄国勤杜虎宋同清曾馥平张立进彭晚霞谭卫宁黄静中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室长沙410125 江西农业大学生态科学研究中心南昌330045 中国科学院环江喀斯特生态系统观测研究站广西喀斯特生态过程与服务重点实验室环江547100 广西石漠化治理产业技术研究院南宁530000 广西木论国家级自然保护区管理中心环江547100

森林生态系统中凋落物养分含量通常具有明显的时空异质性,为探究喀斯特常绿落叶阔叶混交林凋落叶养分含量的时空分布特征及其影响因素,以广西木论喀斯特常绿落叶阔叶混交林25hm2动态监测样地内151个凋落物收集器所收集的凋落叶为研究对... 详细信息

森林生态系统中凋落物养分含量通常具有明显的时空异质性,为探究喀斯特常绿落叶阔叶混交林凋落叶养分含量的时空分布特征及其影响因素,以广西木论喀斯特常绿落叶阔叶混交林25hm2动态监测样地内151个凋落物收集器所收集的凋落叶为研究对象,选取连续12个月的凋落叶进行元素含量分析。结果显示:该森林群落凋落叶元素含量大小顺序为碳(C)>钙(Ca)>氮(N)>镁(Mg)>钾(K)>硫(S)>磷(P),分别介于471.85—496.33、20.27—28.29、17.34—23.10、2.79—5.49、1.80—4.38、1.82—2.22、0.96—1.21g/kg之间,呈现高Ca、Mg,低P、K的分布规律,并且随时间出现明显波动,其中C、N、P、S和Ca元素均在4月出现较大值,而K、Mg则在1月出现峰值。生物因子在5m和10m邻域范围内对凋落叶含量的影响基本一致,但10m尺度上地形因子和土壤因子对凋落叶元素含量的影响更为明显。10m邻域范围内生物和非生物因子对凋落叶P元素的随机森林累积解释率最高,达80.27%,C元素累积解释率最低,仅10.49%,其中海拔和坡度对凋落叶C、N、P、S、K、Ca和Mg含量均有强烈影响,岩石出露率和土壤铁(Fe)含量也会在一定程度上对凋落叶元素含量产生较大影响。综上所述,喀斯特常绿落叶阔叶混交林不同月际间凋落叶养分含量存在显著差异,10m尺度上海拔和坡度是凋落叶养分含量产生空间变异的主要原因。

关键词：凋落物养分时空异质性喀斯特常绿落叶阔叶混交林

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