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High Technology Letters 2012年第3期18卷 230-237页

作者： li jian tang xiaoqiang shao zhufeng yao rui Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 P. R. China

This paper mainly analyzes a hybrid position/force control strategy and experiment of a six-cable driven parallel manipulator for a forty-meter aperture radio telescope. Through the establishments of a kinematic model, a catenary model and a cable-force characteristics model, a basic method is presented based on preventing the pseudo-drag problem of a flexible cable and realizing the hybrid position/force control for a six-cable driven parallel manipulator, and a hybrid position/force control system is developed. Some specific experiments in two typical velocities for astronomical observations are carried out. Experimental results show that the tracking accuracy is related to the speed of the movement. The desired tracking accuracy of the support system is achieved through an effective hybrid position/force control strategy, the cable forces are controlled effectively, and the pseudo-drag problem of flexible cable is solved. This study establishes the foundation of achieving the harmonious movement of the six-cable driven parallel manipulator, A-B rotating platform and the Stewart fine tuninz olatform.

关键词： large radio telescope six-cable driven parallel manipulator hybrid position/forcecontrol tracking accuracy

An unprotected vulnerable relict subtropical conifer-Keteleeria evelyniana: Its forests, populations, growth and endangerment by invasive alien plant species in China

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Plant Diversity 2024年第5期46卷 648-660页

作者： Cindy Q.tang Min-rui Du Huan-Chong Wang You-Cai Shi Jia-Le Zeng Shu-li Xiao Peng-Bin Han jian-Ran Wen Shi-Qian yao Ming-Chun Peng Chong-Yun Wang Yong-Ping li Jordi López-Pujol Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityBuilding#3Guozhong DalouDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of life Sciences Yunnan UniversityShengming Kexueyuan Building#2Chenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina College of Natural Resources Yunnan UniversityChenggong CampusDongwaihuan South RoadUniversity TownChenggong New DistrictKunming 650504YunnanChina Botanic Institute of Barcelona(IBB CSIC-CMCNC)Passeig del Migdia s/nBarcelona 08038CataloniaSpain Escuela de Ciencias Ambientales Universidad Espíritu Santo(UEES)Samborondon 091650Ecuador

Relict subtropical coniferous forests in China face severe fragmentation,resulting in declining populations,and some are under significant threat from invasive alien *** the crucial importance of understanding forest dynamics,knowledge gaps persist,particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria *** this study,we investigated the impact of invasive plants on the regeneration of forests dominated by ***,a subtropical relict species in southwestern *** this purpose,we characterized forest dynamics of 160 forest plots featuring *** as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of *** identified four distinct forest types in which *** was *** found that radial growth of *** trees is faster in younger ageclasses today than it was for older trees at the same *** population structure of *** in each forest type exhibited a multimodal age-class ***,three forest types lacked established saplings younger than 10 years old,a situation attributed to the dense coverage of the invasive alien Ageratina *** invasive species resulted in a reduction of understory species ***,our analysis uncovered a significant negative correlation in phylogenetic relatedness(net relatedness index)between native and invasive alien plant species in eastern *** suggests closely related invasive species face heightened competition,hindering successful *** together,our findings indicate that successful establishment and habitat restoration of *** seedling/saplings require effective measures to control invasive plants.

关键词： Keteleeria evelyniana Age structure Regeneration Species diversity Invasive alien species Phylogenetic relatedness

Triarylamines with branched multi-pyridine groups： modulation of emission properties by structural variation, solvents,and tris(pentafluorophenyl)borane

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Science China Chemistry 2018年第5期61卷 545-556页

作者： rui li Zhong-liang Gong jian-Hong tang Meng-Jia Sun jiang-Yang shao Yu-Wu Zhong jiannian yao CAS Key Laboratory of Photochemistry CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Six triarylamine derivatives 1–6 with branched multi-pyridine substituents were prepared and characterized. These compounds are distinguished by the substituent on one of the phenyl group with NO2 for 1, CN for 2, Cl for 3, p-C6 H4 OMe for 4, OMe for 5,and NMe2 for 6, respectively. As revealed by single crystal X-ray analysis, these substituents play an important role in determining the configuration of the triarylamine framework and the crystal packing of 1–6. The emission properties of these compounds were examined in different solvents(toluene, CH2 Cl2, acetone, tetrahydrofuran(THF), and N,N-dimethylformamide(DMF)) and in solid states. Distinct dual emissions from the localized emissive state and the intramolecular charge transfer state were observed for compound 5 in CH2 Cl2. Compounds 1 and 6 show apparent aggregated enhanced emissions in acetone/H2 *** emission properties of these compounds were further modulated by the addition of tris(pentafluorophenyl)borane. In addition, density functional theory(DFT) and time-dependent DFT(TDDFT) calculations have been performed on the ground and singlet excited states to complement the experimental findings.

关键词： triarylamines luminescence charge-transfer pyridines donor-acceptor

Generation mechanism of quarter buckle in hot-rolled temper rolling

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Journal of Iron and Steel Research International 2022年第10期29卷 1619-1632页

作者： Hui li Guan-yu Zhou An-rui He Zhi-hong Zhang Chi-huan yao Chao liu jian-wei Zhao Wei-gang li jian shao Institute of Engineering Technology University of Science and Technology BeijingBeijing100083China Handan Iron and Steel Group Co. Ltd.Handan056015HebeiChina Engineering Research Centre for Metallurgical Automation and Measurement Technology of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina

To reveal the generation mechanism of the quarter buckle in the process of hot-rolled temper rolling,the elastic–plastic finite element method is used to calculate the deformation of the roll and the strip during the temper *** change of the cross section of the strip and the distribution of the longitudinal stress are analysed under different bending forces to obtain the boundary conditions of the quarter *** generation of the quarter buckle is further analysed from the bending and contact flattening of the roll system and the elastic recovery of the strip after *** found that the quarter buckle is closely related to the high-order distribution of the contact flattening between the work roll and the strip and is less affected by the bending deformation of the roll and the contact flattening between the ***,a new work roll contour of the locally variable crown is proposed to change the distribution of contact flattening between the work roll and the *** is verified through theoretical calculations and industrial applications that the new contour can effectively improve the quarter buckle.

关键词： Quarter buckle Contact flattening Roll contour Finite element method Hot-rolled temper rolling

Field application of non-blasting mechanized mining using high-frequency impact hammer in deep hard rock mine

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Transactions of Nonferrous Metals Society of China 2022年第9期32卷 3051-3064页

作者： shao-feng WANG li-cheng SUN Yu tang Yue JING Xi-bing li Jin-rui yao School of Resources and Safety Engineering Central South UniversityChangsha 410083China Guizhou linhua Group Co. Ltd.Guiyang 550081China

A non-blasting mechanized mining experiment was carried out with a high-frequency impact hammer,and the daily mining performance was recorded to explore the applicability of the high-frequency impact hammer in deep hard rock *** the field application,the scope of the excavation damage zone was monitored,and rock samples were obtained from the ore body to be mined to carry out a series of laboratory *** application results show that the overall excavation efficiency reaches 50.6 t/h,and the efficiency of pillar excavation after excavating stress relief slot reaches 158.2 t/*** results indicate that the non-blasting mechanized mining using high-frequency impact hammer has a good application in deep hard rock mines,and the stress relief slot is conducive to mechanical *** addition,the high-frequency impact hammer also exhibits the advantages of high utilization rate of labor hours,small lumpiness of spalling ore,little dust,and little excavation ***,according to the field application and laboratory experiment results,a non-blasting mechanized mining method for hard rock mines based on high-frequency impact hammer is proposed.

关键词： hard rock mine non-blasting mechanized mining high-frequency impact hammer excavation damage zone stress relief slot mining method

Effects of Conservation Tillage on Crop Yield: a Case Study in the Part of Typical Ecological Zones in China

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Agricultural Sciences in China 2011年第6期10卷 860-866页

作者： tang Qiu-xiang li shao-kun XIE rui-zhi ZHANG jian-xin REN Tian-zhi liN Tao GAO Shi-ju Institute of Crop Science Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Institute of Agricultural Resources and Regionalization Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China Xinjiang University of Agriculture Urumqi 830052 P.R. China Xinjiang Academy of Agricultural Sciences Urumqi 830043 P.R. China

To evaluate the effects of different conservation tillage modes on crop yield in various ecological regions, we interviewed peasant households in the Northeast China Plain, North China Plain, Chengdu Plain, and Northwest China Oasis, China, to analyze the influencing factors of the tillage methods on crop yield. An index set was determined from seven yield parameters based on expert consultation and relevant literature. A comprehensive evaluation of conservation tillage methods in the various ecological regions was carried out using fuzzy theory. The approaches with the highest scores were identified for each region： wide and narrow rotation planting with high stubble standing retention in the Northeast China Plain; seeding after rotary tilled of wheat under corn straw mulching and no-tillage seeding of corn and other crops under wheat straw mulching in the North China Plain; no tillage with high stubble retention in the Northwest China Oasis; and no-tillage seeding of wheat and other crops under rice straw mulching in Chengdu Plain. These research data provide a useful guide for the selection of conservation tillage methods for optimum yields in different regions of China.

关键词： conservation tillage mode farmer recognition yield effect fuzzy mathematics

Quantitative Trait Loci Mapping of Maize Yield and Its Components Under Different Water Treatments at Flowering Time

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Journal of Integrative Plant Biology 2006年第10期48卷 1233-1243页

作者： Gui-He Lu Ji-Hua tang jian-Bing Yan Xi-Qing Ma jian-Sheng li shao-jiang Chen jian-Cang Ma Zhan-Xian liu li-Zhu E Yi-Rong Zhang Jing-rui Dai The National Maize Improvement Center of China China Agricultural University Beijing 100094 China Industrial Crop Institute Shanxi Academy of Agricultural Sciences Fenyang 032200 Shanxi China Zhangye Maize Seed Farm Zhangye 734024 Gansu China

Drought or water stress is a serious agronomic problem resulting in maize （Zea mays L.） yield loss throughout the world. Breeding hybrids with drought tolerance is one important approach for solving this problem. However, lower efficiency and a longer period of breeding hybrids are disadvantages of traditional breeding programs. It is generally recognized that applying molecular marker techniques to traditional breeding programs could improve the efficiency of the breeding of drought-tolerant maize. To provide useful information for use in studies of maize drought tolerance, the mapping and tagging of quantitative trait loci （QTL） for yield and its components were performed in the present study on the basis of the principle of a mixed linear model. Two hundred and twenty-one recombinant inbred lines （RIL） of Yuyu 22 were grown under both well-watered and water-stressed conditions. In the former treatment group, plants were well irrigated, whereas those in the latter treatment group were stressed at flowering time. Ten plants of each genotype were grown in a row that was 3.00 m × 0.67 m （length × width）. The results show that a few of the QTL were the same （one additive QTL for ear length, two additive QTL and one pair of epistatic QTL for kernel number per row, one additive QTL for kernel weight per plant）, whereas most of other QTL were different between the two different water treatment groups. It may be that genetic expression differs under the two different water conditions. Furthermore, differences in the additive and epistatic QTL among the traits under water-stressed conditions indicate that genetic expression also differs from trait to trait. Major and minor QTL were detected for the traits, except for kernel number per row, under water-stressed conditions. Thus, the genetic mechanism of drought tolerance in maize is complex because the additive and epistatic QTL exist at the same time and the major and minor QTL all contribute to phenotype under water-stres

关键词： flowering time maize (Zea mays) quantitative trait loci mapping water treatment yield and its components

Analysis of Clinicopathological Characteristics and Prognosis of Young Patients with Hepatocellular Carcinomaafter Hepatectomy

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Journal of Clinical and Translational Hepatology 2020年第3期8卷 285-291页

作者： Chuan li Kang Chen Xu liu Hao-Tian liu Xiu-Mei liang Guang-Lan liang shao-Tong tang Rong-rui Huo liang Ma Bang-Be Xiang jian-Hong Zhong Le-Qun li Hepatobiliary Surgery Department Guangxi Liver Cancer Diagnosis and Treatment Engineering and Technology Research CenterGuangxi Medical University Cancer HospitalNanningGuangxiChina

Background and Aims:This study was designed to analyze the effects of age and clinicopathological characteristics on prognosis of Chinese patients with hepatocellular carcinoma(HCC).Methods:The clinical data of 2032 HCC patients who were first diagnosed with HCC and underwent curative hepatectomy in our hospital between January 2006 and January 2011 were retrospectively ***:Younger HCC patients(ageliver function,and more frequent vascular invasions than older *** younger patients were suitable for anatomical hepatectomy,and their tumors were found to be at a highly advanced *** recurrence-free survival and overall survival rates of younger HCC patients were significantly worse than those of older patients but this difference disappeared after propensity score *** analysis of pre-matched samples showed that age≤40 years was one of the independent risk factors associated with poor overall ***:Younger patients showed different clinicopathological characteristics than older patients,such as higher rates of hepatitis B infection and advanced *** recurrence-free survival and overall survival rates of younger HCC patients after hepatectomy may be similar to those of older patients.

关键词： Hepatocellular carcinoma Hepatectomy Age Prognosis Overall survival Hepatitis B

Assessment of causal association between thyroid function and lipid metabolism:a Mendelian randomization study

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Chinese Medical Journal 2021年第9期134卷 1064-1069页

作者： Jing-Jia Wang Zhen-Huang Zhuang Chun-li shao Can-Qing Yu Wen-yao Wang Kuo Zhang Xiang-Bin Meng Jun Gao jian Tian Ji-lin Zheng Tao Huang Yi-Da tang Department of Cardiology State Key Laboratory of Cardiovascular DiseaseFuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Department of Epidemiology&Biostatistics School of Public HealthPeking UniversityBeijing 100191China Center for Intelligent Public Health Academy for Artificial IntelligencePeking UniversityBeijing 100191China Department of Cardiology Zhengzhou University People's HospitalCentral China Fuwai HospitalCentral China Branch of the National Cardiovascular CenterHenan Provincial People's HospitalZhengzhouHenan 450003China Department of Cardiology First Affiliated Hospital of Hebei Medical UniversityHebei 050031China Key Laboratory of Molecular Cardiovascular Sciences(Peking University) Ministry of EducationBeijing 100191China department of Cardiology Peking University Third HospitalBeijing 100191China

Background:Thyroid dysfunction is associated with cardiovascular ***,the role of thyroid function in lipid metabolism remains partly *** present study aimed to investigate the causal association between thyroid function and serum lipid metabolism via a genetic analysis termed Mendelian randomization(MR).Methods:The MR approach uses a genetic variant as the instrumental variable in epidemiological studies to mimic a randomized controlled trial.A two-sample MR was performed to assess the causal association,using summary statistics from the Atrial Fibrillation Genetics Consortium(n=537,409)and the Global lipids Genetics Consortium(n=188,577).The clinical measures of thyroid function include thyrotropin(TSH),free triiodothyronine(FT3)and free thyroxine(FT4)levels,FT3:FT4 ratio and concentration of thyroid peroxidase antibodies(TPOAb).The serum lipid metabolism traits include total cholesterol(TC)and triglycerides,high-density lipoprotein,and low-density lipoprotein(LDL)*** MR estimate and MR inverse variance-weighted method were used to assess the association between thyroid function and serum lipid ***:The results demonstrated that increased TSH levels were significantly associated with higher TC(β=0.052,P=0.002)and LDL(β=0.041,P=0.018)*** addition,the FT3:FT4 ratio was significantly associated with TC(β=0.240,P=0.033)and LDL(β=0.025,P=0.027)***,no significant differences were observed between genetically predicted FT4 and TPOAb and serum ***:Taken together,the results of the present study suggest an association between thyroid function and serum lipid metabolism,highlighting the importance of the pituitary-thyroid-cardiac axis in dyslipidemia susceptibility.

关键词： Dyslipidemia Mendelian randomization Analysis lipids Thyroid hormones

Forest characteristics and population structure of a threatened palm tree Caryota obtusa in the karst forest ecosystem of Yunnan,China

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Journal of Plant Ecology 2022年第4期15卷 829-843页

作者： Cindy Q.tang Xia Lu Min-rui Du Shu-li Xiao Shuaifeng li Peng-Bin Han Jia-Le Zeng jian-Ran Wen Shi-Qian yao You-Cai Shi Yun-Fang li Ming-Chun Peng Chong-Yun Wang Zhi-Ying Zhang Institute of Ecology and Geobotany College of Ecology and Environmental ScienceYunnan UniversityKunming 650504China Research Institute on Resource Insects Chinese Academy of ForestryKunming 650224China Management Office of Yunlong Tianchi National Nature Reserve GuolangDali PrefectureYunnan 672700China

Caryota obtusa of Arecaceae is a fascinating palm tree native to southwestern China,India,Myanmar,Thailand,Laos and *** is an economically important and threatened species and appears as a canopy dominant in some karst areas in *** aim to clarify the forest structure,species diversity,population status and regeneration dynamics of *** in the karst forest ecosystem of Yunnan,*** established 56 vegetation plots dominated by *** in 10 counties of southern *** on the plot data,we analyzed the community stratification,floristic composition and ***’s population *** used questionnaires to interview local people and recorded the human activity history in ***-dominated *** obtusa palm forests were distributed on limestone mountain slopes and *** were seven forest community *** stratification of each community included arborous layer,shrub layer and *** communities had rich species *** all the plots as a whole of each community type,Shannon–Wiener diversity index of either woody or herbaceous species ranged from 2.1 to *** diameter at breast height(DBH)-class frequency distribution of *** was a multimodal *** regeneration was sporadic and dependent on intermediate natural *** the current population structure,a number of *** trees with small DBHs consisted mainly of the forest communities with no or a slight degree of human *** human activities terribly hindered recruitment of ***,followed by the medium intensity of human activities.

关键词： Caryota obtusa community structure species diversity population structure regeneration dynamics human disturbance