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Numerical Simulation and Experimental Study on Interlock Deformation for Roll Formed U-Section Steel Piling

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Journal of Iron and Steel Research International 2013年第11期20卷 41-45页

作者： FENG Guang-hong ZHANG Pei ZHANG Hong-liang zhou Xu-chang ZHAO Yong Metallurgical Technology Institute Central Iron and Steel Research Institute Taian Kenuo Profile Steel Co. Ltd.

The interlock of a roll formed U-section sheet steel piling under loading was analyzed by means of numeri- cal simulation, and meanwhile the tensile failure experiment was conducted. The results indicated that under the same load, the interlock corners of roll formed steel piling are not only the regions with the lowest safety factor, but also the regions with the highest stress; there are two slippages in the tensile instability process of interlock, Each slippage can be regarded as a failure, and different types of failure mode should be used to evaluate the performance of steel pilings according to different applications. Due to the work hardening effect during the roll forming process, the hardness of the interlock material increases by 16% compared with that of the original sheet steel. It was also found that the instability strength obtained in tensile failure test is only 15.6 % of the tensile strength of the original sheet steel.

关键词： roll formed sheet steel piling interlock numerical simulation instability

New edge detection method for high-resolution SAR images

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Journal of Systems Engineering and Electronics 2006年第2期17卷 316-320页

作者： chang Yulin zhou Zhimin chang Wenge Jin Tian School of Electronic Science and Engineering National Univ. of Defense Technology Changsha P. R. China

A new edge detection method combining the scanning window central edge （SWCE） detector and an improved active contour model is proposed. The method first emploies the SWCE detector based on the difference of area pixel value means to perform an optimal edge detection, and then proposes an improved active contour model with modified energy functions to refine the location of the edges. The initial nodes of the improved active contour model are automatically found from the vectorised results of the SWCE detector. Tests on simulated speckled images and real airborne SAR images show that the combined method can benefit from the advantages of the both techniques and get satisfactory edge detection and localization abilities at the same time.

关键词： index terms -SAR edge detection SWCE active contour model.

Porous carbon nanofibers derived from low-softening-point coal pitch towards all-carbon potassium ion hybrid capacitors

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Rare Metals 2022年第11期41卷 3706-3716页

作者： Guang-Yuan Wang Xiao-Hong Wang Jin-Feng Sun Ya-Min Zhang Lin-Rui Hou chang-zhou Yuan School of Materials Science and Engineering University of JinanJinan250022China

Potassium ion hybrid capacitors(PIHC)have promising applications in medium and large-scale energy storage systems due to their high energy/power density,abundant potassium resource and low ***,the slow kinetics of battery-type anodes originating from the large-size K+results in a mismatch between the two electrodes,rendering the modest energy density of ***,we first develop an electrospinning strategy to successfully synthesize fibrous precursor by using the HNO_(3)pre-oxidized low-softening-point coal pitch as the low-cost raw *** further carbonization or KOH activation,the two types of carbon nanofibers(CNF)are fabricated as anode and cathode materials,respectively,towards the dual-carbon PIHC *** to its threedimensional interconnected porous conducting network and large layer spacing,the resulted CNF anode material is endowed with high reversible capacities,excellent rate and long cycle ***,the activated CNF cathode with a large surface area of 2169 m^(2)·g^(-1)exhibits excellent capacitive performance.A PIHC constructed with the two fibrous electrodes delivers an energy density of110.0 Wh·kg^(-1)at 200.0 W kg^(-1),along with a capacitance retention of 83.5%after 10,000 cycles at 1.0 A·g^(-1).The contribution here provides a cost-efficiency avenue and platform for advanced dual-carbon PIHC.

关键词： Potassium ion hybrid capacitors(PIHC) Low-softening-point coal pitch Carbon nanofibers(CNF) Dual-carbon devices Long durability

Development of a sensitive and reliable droplet digital PCR assay for the detection of ‘Candidatus Liberibacter asiaticus'

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Journal of Integrative Agriculture 2018年第2期17卷 483-487页

作者： ZHONG Xi LIU Xue-lu LOU Bing-hai zhou chang-yong WANG Xue-feng National Citrus Engineering Research Center Citrus Research Institute Chinese Academy of Agricultural Sciences/Southwest University Guangxi Key Laboratory of Citrus Biology Guangxi Academy of Specialty Crops

Citrus Huanglongbing（HLB, yellow shoot disease） is one of the most serious citrus diseases worldwide. To better improve the detection sensitivity, a droplet digital PCR（ddPCR） assay was developed for the rapid detection of ‘Candidatus Liberibacter asiaticus＇（Las）, the putative causal agent of HLB. The detection of sensitivity comparison using positive plasmid indicated that dd PCR was superior to quantitative PCR（qPCR） for detecting and quantifying Las at low concentrations. The Las detection of 40 field samples also showed that six of 13 asymptomatic samples（46.15%） with high Ct value（〉35） were positive by dd PCR. This methodology showed great potential for early HLB infection diagnosis.

关键词： citrus Huanglongbing early diagnosis droplet digital PCR

Preliminary Studies on Species and Distribution of Citrus Viroids in China

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Agricultural Sciences in China 2008年第9期7卷 1097-1103页

作者： WANG Xue-feng zhou chang-yong TANG Ke-zhi LAN Jian-qiang zhou Yan LI Zhong-an Citrus Research Institute Chinese Academy of Agricultural Sciences Chongqing 400712 P.R.China Key Laboratory of Agricultural Biodiversity for Plant Disease Management Ministry of Education Yunnan Agricultural University Kunming 650201 P.R.China

Citrus viroids are the small but economically important RNA pathogens. For investigating their occurrence and distribution in China, 65 viroid samples collected from 8 major citrus cultivated regions were evaluated using one-step or multiplex onestep RT-PCR and biological indexing for specifically detection of Citrus exocortis viroid （CEVd）, Citrus bent leaf viroid （CBLVd）, Hop stunt viroid （HSVd）, Citrus viroid-Ⅲ （CVd-Ⅲ） and Citrus viroid-Ⅳ （CVd-Ⅳ）. The results showed that there were at least 4 kinds of citrus viroids （CEVd, CBLVd, HSVd, and CVd-Ⅲ） on citrus trees in China. Most of the infected citrus plants harbored more than one viroid species, and two plants were infected with up to 4 citrus viroids. Sweet orange was more frequently infected by viroids than other citrus varieties. It is the preliminary report on the species and distribution of citrus viroids in China.

关键词： citrus viroids exocortis cachexia multiplex one-step RT-PCR

Baseflow variations and its causes in a subtropical watershed of southern China

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Journal of Mountain Science 2022年第10期19卷 2817-2829页

作者： LIU Zheng SHENG Fei LIU Shi-yu WANG Yan-yan zhou chang-ming GU Chao-jun School of Land Resources and Environment Jiangxi Agricultural UniversityNanchang 330045China Key Laboratory of Poyang Lake Watershed Agricultural Resources and Ecology of Jiangxi Province Nanchang 330045China College of Resources and Environment Huazhong Agricultural UniversityWuhan 430070China Yangtze River Basin Monitoring Center Station for Soil and Water Conservation Changjiang Water Resources CommissionWuhan 430012China

Baseflow is an essential component of streamflow and plays a crucial role in maintaining the stability of ***,few quantitative studies have identified the effects of leading factors on baseflow variation at the small watershed scale,especially in subtropical *** this study,the small watershed(Pengchongjian watershed,2.90 km2),located in Southern China,was considered to explore the quantitative impact of precipitation,evapotranspiration,temperature,and vegetation restoration on *** digital filter method was used to separate baseflow by daily streamflow records from 1983 to *** stepwise regression models were developed for selecting significant influencing factors of baseflow at seasonal and annual *** direct and indirect effects,as well as their quantitative relationships between baseflow and multiple factors,were clarified by the path *** results showed that filtered average annual baseflow significantly decreased(p<0.05),ranging from 72.82 to 305.85 mm,and the average yearly baseflow index was *** addition,various significant influencing factors of baseflow had different direct and indirect effects on baseflow at seasonal and annual *** precipitation was the dominant factor with respect to the direct impact,which directs path coefficient was 0.891 in spring,0.823 in summer,1.599 in autumn,1.332 in winter,and 0.917 in an annual scale,*** terms of the indirect effects,evapotranspiration played a leading role during the spring,autumn,winter,and annual scale,whereas the average temperature was the dominant factor during the ***,results demonstrated that the baseflow variation was mainly attributed to climate *** present works are beneficial for revealing the internal mechanism of the baseflow variations in the study area,and it can provide a scientific basis for managing water resources in the watershed.

关键词： Baseflow separation Baseflow index Climate change Groundwater Pengchongjian watershed

Preliminary Studies on CPG/Hinf Ⅰ RFLP Groups of Citrus tristeza virus Infected Sweet Oranges in China

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Agricultural Sciences in China 2006年第1期5卷 39-44页

作者： XU Xiao-feng zhou chang-yong SONG Zhen YANG Fang-yun Citrus Research Institute Chinese Academy of Agricultural Sciences Chongqing 400712 P.R.China College of Plant Protection Southwest University Chongqing 400716 P.R.China

Citrus tristeza virus （CTV） causes economically important losses to the citrus industry worldwide. Mild strain cross protection （MSCP） against tristeza has hardly been practised due to mixed infection of different CTV-strains and little background of its molecular biology in China. For better cognition on CTV, 192 sweet orange samples collected from eight provinces （Chongqing, Sichuan, Fujian, Hunan, Guangxi, Yunnan, Guangdong and Jiangxi） were tested by direct tissue blot immuno-assay （DTBIA）, and 158 of them were tested positively, which therefore were subjected to coat protein gene （CPG）/Hinf Ⅰ restriction fragment length polymorphism （RFLP） analysis. Sample bulks were compared between Chongqing and Fujian by some statistical data, including ratios of single infection and mixed infection to local samples, proportions of CTV isolates with single RFLP groups, and rates of each RFLP group. The simplified analysis of samples from the other six provinces were then conducted. This study suggests that CTV isolates with CPG/Hinf Ⅰ RFLP groups Ⅲ and Ⅰ are the main epidemic ones in China, and mixed infection of CTV in fields are popular. Based on observation of severity of stem-pitting symptom in field trees, CTV isolates with CPG/Hinf Ⅰ RFLP groups Ⅲ and Ⅰ caused severe stem-pittings in sweet oranges in China.

关键词： Citrus tristeza virus (CTV) CPG/Hinf Ⅰ RFLP groups stem-pitting sweet orange

A glimpse into the biodiversity of insects in Yunnan: An updated and annotated checklist of butterflies(Lepidoptera, Papilionoidea)

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Zoological Research 2022年第6期43卷 1009-1010页

作者： Tian-Tian Yu zhou chang Zhi-Wei Dong Kai-Qin Li Fang-zhou Ma Wen Wang Xue-Yan Li State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Kunming Natural History Museum of Zoology Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Nanjing Institute of Environmental Sciences National Key Laboratory on Biosafety of Ministry of Ecology and EnvironmentNanjingJiangshu 210042China

DEAR EDITOR, We provide an annotated checklist of the butterflies of Yunnan, which includes 356 genera and 1 300 species in six families. The number of butterfly genera and species in Yunnan accounts for 79.8% and 58.6% of China’s total records, respectively. Thus, our study reveals that Yunnan has the highest butterfly diversity in China. This updated checklist also reports two genera and 18 species newly recorded from China as well as 36 species first recorded from Yunnan.

关键词： biodiversity Papilio China

V_(2)CT_(x) MXene and its derivatives:synthesis and recent progress in electrochemical energy storage applications

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Rare Metals 2022年第3期41卷 775-797页

作者： Zhao-Lin Tan Jing-Xuan Wei Yang Liu Fakhr uz Zaman Wajid Rehman Lin-Rui Hou chang-zhou Yuan School of Materials Science and Engineering University of JinanJinan 250022China Department of Chemistry Hazara UniversityMansehra 21120Pakistan

With the continuous development of two-dimensional (2D) transition metal carbides and nitrides(collectively referred to as MXene).Nowadays,more than 70 MXene materials have been discovered,and the number is still *** them,the V_(2)CT_(x) MXene has attracted considerable attentions due to its outstanding physical and chemical *** this review,we mainly discussed the emerging V_(2)CT_(x) MXene and its derivative systems in various energy storage ***,an introduction of the V-based MXene and its derivatives along with their synthetic methodologies is provided,then we summarize their applications in specific energy storage devices,such as metal (Li,Na,K,Mg,Zn and Al) ion batteries,lithium-sulfur batteries,supercapacitors and metal-ion ***,the main challenges and future perspectives existing in V-based MXene and its derivatives are reasonably put forward.

关键词： MXene V_(2)CT_(x) Two-dimensional material Derivatives Electrochemical energy storage applications