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Design and calibration of spoke piezoelectric six-dimensional force/torque sensor for space manipulator

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Chinese Journal of Aeronautics 2024年第1期37卷 218-235页

作者： yingjun li Guicong WANG Shuai ZHANG Yuanqin ZHOU Hongyu li Zhenguang QI School of Mechanical Engineering University of JinanJinan 250022China

The large manipulator outside the space cabin is a multi-degree of freedom actuator for space *** order to realize the automatic control and flexible operation of the space manipulator,a novel spoke structure piezoelectric six-dimensional force/torque sensor with redundancy ability,high stiffness and good decoupling performance is innovatively *** on the deformation coordination relationship,the redundancy measurement mechanism is *** mathematical models of the sensor with and without branch fault are established *** finite element model is established to verify the feasibility of structure and redundancy measuring principle of the *** on the theoretical analysis and simulation analysis,the prototype of the sensor is *** and dynamic calibration experiments are carried *** actual output voltage signal of the six-dimensional force/torque sensor is collected to establish the equation between the standard input applied load and the actual output voltage *** on ant colony optimized BP algorithm,performance indexes of the sensor with and without branch fault are analyzed *** experimental results show that the spoke piezoelectric sixdimensional force/torque sensor with the eight-point support structure has good accuracy and ***,it has strong decoupling characteristic that can effectively shield the coupling between *** nonlinear errors and maximum interference errors of decoupled data with and without branch faults are less than 1% and 2%,*** natural frequency of the sixdimensional force sensor can reach 2856.45 Hz and has good dynamic *** research content lays a theoretical and experimental foundation for the design,development and application of the new six-dimensional force/torque sensors with ***,it will significantly improve the research level in this field,and provide a strong guarantee for the smoot

关键词： Decoupling algorithm Piezoelectric Redundancy Six-dimensional force/torque sensor Space manipulator

CRISPR-based gene editing technology and its application in microbial engineering

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Engineering Microbiology 2023年第4期3卷 67-79页

作者： Junwei Wei yingjun li State Key Laboratory of Agricultural Microbiology and College of life Science and Technology Huazhong Agricultural UniversityWuhan 430070China

Gene editing technology involves the modification of a specific target gene to obtain a new function or *** advances in clustered regularly interspaced short palindromic repeats(CRISPR)-Cas-mediated technolo-gies have provided an efficient tool for genetic engineering of cells and ***,we review the three emerging gene editing tools(ZFNs,TALENs,and CRISPR-Cas)and briefly introduce the principle,classification,and mechanisms of the CRISPR-Cas *** for gene editing based on endogenous and exogenous CRISPR-Cas systems,as well as the novel base editor(BE),prime editor(PE),and CRISPR-associated transposase(CAST)technologies,are described in *** addition,we summarize recent developments in the application of CRISPR-based gene editing tools for industrial microorganism and probiotics ***,the potential challenges and future perspectives of CRISPR-based gene editing tools are discussed.

关键词： CRISPR-Cas system Gene editing Industrial microorganisms Probiotics

Response of Pinus taiwanensis growth to climate changes at its southern limit of Daiyun Mountain, China's Mainland Fujian Province

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Science China Earth Sciences 2016年第2期59卷 328-336页

作者： CHEN Dan FANG KeYan li yingjun DONG ZhiPeng ZHANG Yu ZHOU FeiFei Institute of Geography Key Laboratory of Humid Subtropical Eco-geographical Process (Ministry of Education)College of Geographical Sciences Fujian Normal University Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences Research Center for Scientific Development in Fenhe River Valley Taiyuan Normal University

The Pinus taiwanensis trees of a Chinese endemic species form pure forests at infertile sites in humid subtropical China, which can aid soil reservation and ecological resiliency at such sites. Herein, we used dendrochronological methods to investigate the growth patterns and their relationship with climate by analyzing 158 cores of 79 P. taiwanensis trees at 4 sites in their southernmost distribution in China's Mainland at Daiyun Mountain in Fujian Province. Tree growths at sites with favor- able conditions generally showed an age-related growth trend, which decreased from approximately 5 mm to 0.5 mm in about a century. Trees in moderately stressed environments established high growth in their juvenile periods but were highly suscep- tible to environmental stresses such as a sharp growth decline in the 1990s. The temperature in February and the moisture in July are the major limiting factors for most of the tree growths, except for a few extremely stressed P. taiwanensis trees. The growth of the dwarf P. taiwanensis trees, with all ring diameters of the first 20 years less than 4 ram, is mainly limited by the dry climate in May. Under the potential future warming trend, drought stress can be particularly threatening to these dwarf P. taiwanensis trees, which are likely to be the germplasm resources for this species in this region.

关键词： Daiyun Mountain Pinus taiwanensis Climate-growth relationships Drought Global warming

Genetic technologies for extremely thermophilic microorganisms of Sulfolobus, the only genetically tractable genus of crenarchaea

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Science China(life Sciences) 2017年第4期60卷 370-385页

作者： Nan Peng Wenyuan Han yingjun li Yunxiang liang Qunxin She State Key Laboratory of Agricultural Microbiology College of Life Science and Technology Huazhong Agricultural University Archaeal Centre Department of Biology University of Copenhagen

Archaea represents the third domain of life, with the information-processing machineries more closely resembling those of eukaryotes than the machineries of the bacterial counterparts but sharing metabolic pathways with organisms of Bacteria, the sister prokaryotic phylum. Archaeal organisms also possess unique features as revealed by genomics and genome comparisons and by biochemical characterization of prominent enzymes. Nevertheless, diverse genetic tools are required for in vivo experiments to verify these interesting discoveries. Considerable efforts have been devoted to the development of genetic tools for archaea ever since their discovery, and great progress has been made in the creation of archaeal genetic tools in the past decade. Versatile genetic toolboxes are now available for several archaeal models, among which Sulfolobus microorganisms are the only genus representing Crenarchaeota because all the remaining genera are from Euryarchaeota. Nevertheless, genetic tools developed for Sulfolobus are probably the most versatile among all archaeal models, and these include viral and plasmid shuttle vectors, conventional and novel genetic manipulation methods, CRISPR-based gene deletion and mutagenesis, and gene silencing, among which CRISPR tools have been reported only for Sulfolobus thus far. In this review, we summarize recent developments in all these useful genetic tools and discuss their possible application to research into archaeal biology by means of Sulfolobus models.

关键词： plasmid promoter prokaryotic shuttle mutagenesis deletion silencing genomics diverse genera

High-efficiency genome editing of an extreme thermophile Thermus thermophilus using endogenous type I and type III CRISPR-Cas systems

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mlife 2022年第4期1卷 412-427页

作者： Jinting Wang Junwei Wei Haijuan li yingjun li State Key Laboratory of Agricultural Microbiology and College of life Science and Technology Huazhong Agricultural UniversityWuhanChina Shenzhen Institute of Nutrition and Health Huazhong Agricultural UniversityShenzhenChina Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenChina College of Biological and Environmental Engineering Xi'an UniversityXi'anChina

Thermus thermophilus is an attractive species in the bioindustry due to its valuable natural products,abundant thermophilic enzymes,and promising fermentation ***,efficient and versatile genome editing tools are not available for this *** this study,we developed an efficient genome editing tool for *** HB27 based on its endogenous type IB,I-C,and III-A/B CRISPR-Cas ***,we systematically characterized the DNA interference capabilities of the different types of the native CRISPR-Cas systems in *** *** found that genomic manipulations such as gene deletion,mutation,and in situ tagging could be easily implemented by a series of genome-editing plasmids carrying an artificial self-targeting mini-CRISPR and a donor DNA responsible for the recombinant *** also compared the genome editing efficiency of different CRISPR-Cas systems and the editing plasmids with donor DNAs of different ***,we developed a reporter gene system for *** based on a heat-stableβ-galactosidase gene TTP0042,and constructed an engineered strain with a high production capacity of superoxide dismutases by genome modification.

关键词： endogenous CRISPR-Cas system genome editing reporter gene SOD production Thermus thermophilus

Auxin regulation and MdPIN expression during adventitious root initiation in apple cuttings

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Horticulture Research 2020年第1期7卷 955-966页

作者： ling Guan yingjun li Kaihui Huang Zong-Ming(Max)Cheng College of Horticulture Nanjing Agricultural University210095 NanjingChina Institute of Pomology Jiangsu Academy of Agricultural SciencesJiangsu Key Laboratory for Horticultural Crop Genetic Improvement210014 NanjingChina Department of Plant Sciences University of TennesseeKnoxvilleTN 37831USA

Adventitious root(AR)formation is critical for the efficient propagation of elite horticultural and forestry *** decades of research,the cellular processes and molecular mechanisms underlying AR induction in woody plants remain *** examined the details of AR formation in apple(Malus domestica)M.9 rootstock,the most widely used dwarf rootstock for intensive production,and investigated the role of polar auxin transport in postembryonic *** formation begins with a series of founder cell divisions and elongation of the interfascicular cambium adjacent to vascular *** process is associated with a relatively high indole acetic acid(IAA)content and hydrolysis of starch *** auxin treatment promoted this cell division,as well as the proliferation and reorganization of the endoplasmic reticulum and Golgi *** contrast,treatment with the auxin transport inhibitor N-1-naphthylphthalamic acid(NPA)inhibited cell division in the basal region of the cuttings and resulted in abnormal cell divisions during the early stage of AR *** addition,PIN-FORMED(PIN)transcripts were differentially expressed throughout the whole AR development *** also detected upregulation of MdPIN8 and MdPIN10 during induction;upregulation of MdPIN4,MdPIN5,and MdPIN8 during extension;and upregulation of all MdPINs during AR *** research provides an improved understanding of the cellular and molecular underpinnings of the AR process in woody plants.

关键词： hydrolysis elite dwarf

Simulating liquid-vapor phase separation under shear with lattice Boltzmann method

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Science China(Physics,Mechanics & Astronomy) 2009年第10期52卷 1337-1344页

作者： WANG Ce XU AiGuo ZHANG GuangCai li yingjun China University of Mining and Technology Beijing 100083China National Key Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China

We study liquid-vapor phase separation under shear via the Shan-Chen lattice Boltzmann model. Besides the rheological characteristics, we analyze the Kelvin-Helmholtz (K-H) instability resulting from the tangential velocity difference of the fluids on two sides of the interface. We discuss also the growth behavior of droplets. The domains being close to the walls are lamellar-ordered, where the hydrodynamic effects dominate. The patterns in the bulk of the system are nearly isotropic, where the domain growth results mainly from the diffusion mechanism. Both the interfacial tension and the K-H instability make the liquid-bands near the walls tend to rupture. When the shear rate increases, the inequivalence of evaporation in the upstream and coagulation in the downstream of the flow as well as the role of surface tension make the droplets elongate obliquely. Stronger convection makes easier the transferring of material particles so that droplets become larger.

关键词： lattice Boltzmann method the shan-chen model K-H instability phase separation

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Relationship between the characteristics of landforms and sediments as well as the plume front in the Hangzhou Bay

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Acta Oceanologica Sinica 1993年第1期12卷 133-144页

作者： Feng yingjun li Yan and li Bogen Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China

Sedimentary environments in the Hangzhou Bay are introduced by a three-subregional landform pattern and a sedimentation map with six major sedimentation types. The geographic setting, sediment transportation and sedimentation in different subregions are discussed with sediment grain parameters. Sedimentary basin suffering from effect of plume front can be identified by the fine sediments with median ( Mdφ ) 7φ-8φ, clay content 30% - 40% and silt 60% - 70%. Sediment transportation along the plume front seems not to be a direct effect on sedimentary formation of the shoals fringing the south coast of the Hangzhou Bay.

关键词： Relationship between the characteristics of landforms and sediments as well as the plume front in the Hangzhou Bay well

Influence of interlayer on characteristics of Kelvin-Helmholtz instability

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强激光与粒子束 2016年第7期28卷 42-47页

作者： Cheng Tao li Nun li yingjun (School of Science China University of Mining and Technology Beijing 100083 China)

Characteristics of the Kelvin-Helmholtz （KH） instability of the interfaces formed by two semi-infinitely distributed fluids and one interlayer were studied. It was found that the coupling effects between theinterfaces should be considered if the interlayer thickness was less than 0. 5 times of the disturbation wave-length. And the degenerate modes could be produced in the situation with proper parameters.

关键词： plasma KH instability interface coupling