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Chinese j.urnal of Electrical Engineering 2024年第1期10卷 1-2页

作者： li j. Mei H. li S. Tianj.n University China Tsinghua Shenzhen International Graduate School China Lanzhou j.aotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power equipment.The performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new situation.Nondestructive detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the obj.ct.

关键词： service Application operation

Surface Characterisation of Silicon Based MEMS

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Chemical Research in Chinese Universities 2004年第4期20卷 407-410页

作者： li j. CUI Z M. A. Baker The Surface Analysis Laboratory School of Engineering University of SurreyRutherford Appleton LaboratoryThe Surface Analysis Laboratory School of Engineering University of Surrey Guildford GU2 7XH UKChilton Didcot UKGuildford GU2 7XH UK

Polysilicon Microelectromechanical systems(MEMS) are the subj.ct of intensive researches. Surface chemistry and topography of a MEMS test structure fabricated at Sandia National Laboratory, USA, were studied by means of scanning electron microscopy(SEM), X-ray photoelectron spectroscopy(XPS) and atomic force microscopy(AFM). XPS C_ 1sand Si_ 2pspectra from the polysilicon components, silicon nitride substrate and a reference silicon wafer were compared. The results confirm the presence of a self-assembled monolayer(SAM) on the MEMS surface. An island-like morphology was found on both polysilicon and silicon nitride surfaces of the MEMS. The islands take the form of caps, being up to 0.5 μm in diameter and 20 nm in height. It is concluded that the co-existence of columnar growth and equiaxed growth during the low pressure chemical vapor deposition(LPCVD) of these layers leads to the observed morphology and the islands are caps to the columnar structures.

关键词： Microelectromechanical systems XPS Atomic force microscopy

PROPERTIES OF THREE-DIMENSIONAL MOVEMENT OF SANDY WATER DISCHARGED INTO A LAKE

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j.urnal of Hydrodynamics 2001年第2期13卷 72-76页

作者： Deng, Y. li, j. li, K.F. Zhao, W.Q. State Key Lab. of High Speed Flow Sichuan Univ. Chengdu 610065 China

A Random Traj.ctory Model (RTM) for solid-liquid two-phase flow based on the Lagrangian Method is presented in this paper. The effects of water drag force, pressure gradient force, buoyancy and virtual mass force on the particles were included and the turbulent dispersion was modeled by random method. Three-dimensional k-Ε model was used to calculate the flow field. A pumped-storage power station, with a natural lake as its upper pool, was taken as a case for the study. Averaged movement traj.ctories, velocities and the volume-concentration distributions for 5 groups of sediment particles, were predicted with RTM. The possible silted locations in the lake were also predicted.

关键词： Boundary conditions Computer simulation Lakes Sand Three dimensional Two phase flow Velocity

Synthesis and Catalyzing Behavior of Olefin Polymerization of cis-Cyclopentene Bridged Titanocenes

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Chinese Chemical Letters 2000年第11期11卷 979-980页

作者： li j.S. Xiong C.H. Ma Y.Q. li j. Chen X. Inst. of Elemento-Organic Chemistry Nankai University Tianjin 300071 China Department of Chemistry Tianjin Normal University Tianjin 300070 China

Two cis-cyclopentene bridged titanocenes have been synthesized. Two homogeneous Ziegler catalysts prepared by activation of synthesized compounds with methylalumoxane are active for ethylene polymerization reactions.

关键词： cis Ti Synthesis and Catalyzing Behavior of Olefin Polymerization of cis-Cyclopentene Bridged Titanocenes

Virtual Screening and Mechanism of Action of DPP-IV Inhibitory Peptides from Pinctada fucata (P. fucata)

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Science and Technology of Food Industry 2021年第16期42卷 1-7页

作者： li j. Su j. Chen M. Dai S. Gao Y. Yin H. The Equipment Public Service Center CAS Key Laboratory of Tropical Marine Bio-resources and Ecology Chinese Academy of Sciences South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China University of Chinese Academy of Sciences Beijing 100049 China Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) Guangzhou 511458 China

In order to discover the dipeptidyl peptidase IV (DPP-IV) peptides quickly from Pinctada fucata (P. fucata), in this research, 20 reported DPP-IV inhibitory peptides in the database were used to form a training set and construct pharmacophore models, which were then valuated by test set molecules and fisher random validation. The online website PeptideCutter was employed to perform the virtual hydrolysis with P. fucata meat protein as raw materials. The optimal pharmacophore model (Hypo1) was used to initially screen the 192 low-molecular peptides (the number of amino acids was no more than 5), which were obtained by the virtual hydrolysis, and then the molecular docking was performed for further screening. Furthermore, the potential DPP-IV inhibitory peptides were synthesized using a solid-phase method, and their activities were verified in vitro and the interaction mechanism was analyzed. The results showed that 4 potential DPP-IV inhibitory peptides, namely LPIY, VQDR, PIY, and APSL were screened through pharmacophore combined with molecule docking. Among them, VQDR and PIY did not show inhibitory activity, while LPIY and APSL had strong DPP-IV inhibitory activity, with IC50 values of 521.19 and 258.67 μmol/L respectively. The interaction mechanism indicated both peptides formed multiple hydrogen bonds with the amino acid residues within the active pocket of DPP-IV, and the proline (P) at the second position of the N-terminal constructed Pi-Alkyl interactions with the residues of the active pocket, which promoted the DPP-IV inhibitory activity for LPIY and APSL. The current work would provide a theoretical method for screening DPP-IV inhibitory peptides derived from P. fucata efficiently. © 2021 Editorial Department of Science and Technology of Food Science. All rights reserved.

关键词： dipeptidyl peptidase IV (DPP-IV) molecular docking peptides pharmacophore model Pinctada fucata (P. fucata)

Ubiquitin-Specific Protease 14 （UBP14） Is Involved in Root Responses to Phosphate Deficiency in Arabidopsis

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Molecular Plant 2010年第1期3卷 212-223页

作者： Wen-Feng li Paula j. Perry Nulu N. Prafulla Wolfgang Schmidt Institute of Plant and Microbial Biology Academia Sinica 115 Taipei

A mutant isolated from a screen of EMS-mutagenized Arabidopsis lines, per1, showed normal root hair development under control conditions but displayed an inhibited root hair elongation phenotype upon Pi deficiency. Additionally, the per1 mutant exhibited a pleiotropic phenotype under control conditions, resembling Pi-deficient plants in several aspects. Inhibition of root hair elongation upon growth on low Pi media was reverted by treatment with the Pi analog phosphite, suggesting that the mutant phenotype is not caused by a lack of Pi. Reciprocal grafting experiments revealed that the mutant rootstock is sufficient to cause the phenotype. Complementation analyses showed that the PER1 gene encodes an ubiquitin-specific protease, UBP14. The mutation caused a synonymous substitution in the 12th exon of this gene, resulting in a lower abundance of the UBP14 protein, probably as a consequence of reduced translation efficiency. Transcriptional profiling of per1 and wild-type plants subj.cted to short-term Pi starvation revealed genes that may be important for the signaling of Pi deficiency. We conclude that UBP14 function is crucial for adapting root development to the prevailing local availability of phosphate.

关键词： Phosphate deficiency root hairs ubiquitin-specific protease root development.

Precise genome-editing in human diseases:mechanisms,strategies and applications

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1065-1085页

作者： Yanj.ang Zheng Yifei li Kaiyu Zhou Tiange li Nathan j.VanDusen Yimin Hua Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE Department of PediatricsWest China Second University HospitalSichuan UniversityChengduSichuan 610041China Department of Cardiovascular Surgery West China HospitalSichuan UniversityChengduSichuan 610041China Department of Pediatrics Herman B Wells Center for Pediatric ResearchIndiana University School of MedicineIndianapolisIN 46202USA

Precise genome-editing platforms are versatile tools for generating specific,site-directed DNA insertions,deletions,and substitutions.The continuous enhancement of these tools has led to a revolution in the life sciences,which promises to deliver novel therapies for genetic disease.Precise genome-editing can be traced back to the 1950s with the discovery of DNA’s doublehelix and,after 70 years of development,has evolved from crude in vitro applications to a wide range of sophisticated capabilities,including in vivo applications.Nonetheless,precise genome-editing faces constraints such as modest efficiency,delivery challenges,and off-target effects.In this review,we explore precise genome-editing,with a focus on introduction of the landmark events in its history,various platforms,delivery systems,and applications.First,we discuss the landmark events in the history of precise genome-editing.Second,we describe the current state of precise genome-editing strategies and explain how these techniques offer unprecedented precision and versatility for modifying the human genome.Third,we introduce the current delivery systems used to deploy precise genome-editing components through DNA,RNA,and RNPs.Finally,we summarize the current applications of precise genome-editing in labeling endogenous genes,screening genetic variants,molecular recording,generating disease models,and gene therapy,including ex vivo therapy and in vivo therapy,and discuss potential future advances.

关键词： precise generating editing

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黏性瑞利泰勒问题的线性稳定性理论与验证

黏性瑞利泰勒问题的线性稳定性理论与验证

性成熟雄蜂和觅食蜜蜂触角蛋白质组比较（英文）

中国力学大会-2015

作者：谢晨月陶建军 li j. 北京大学工学院力学与工程科学系湍流与复杂系统国家重点实验室 Department of Engineering University of Cambridge

对于黏性流体的瑞利泰勒不稳定性(VRTI)问题,由于色散关系的复杂性线性理论无法给出解析解,而以往的近似解的最大相对误差在12%。另外,VRTI的线性理论迄今为止仍未在完整的波数范围内被验证过。本文给出了VRTI一个解析的近似解,不但可...

对于黏性流体的瑞利泰勒不稳定性(VRTI)问题,由于色散关系的复杂性线性理论无法给出解析解,而以往的近似解的最大相对误差在12%。另外,VRTI的线性理论迄今为止仍未在完整的波数范围内被验证过。本文给出了VRTI一个解析的近似解,不但可以显式地反应黏性的作用,而且将

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性成熟雄蜂和觅食蜜蜂触角蛋白质组比较（英文）

EFFECTS OF TREATMENT TIME ON CORROSION OF DIFFUSION-ALLOYED COATINGS OF PURE MAGNESIUM

作者： li j. Aleku D.W. Han B.

蜜蜂已经进化出复杂精细的化学交流系统去调节他们错综复杂的社会互动,与气味检测相关的特殊蛋白质很可能在这种化学交流中起作用。气味接收过程主要发生在触角的一个被称作嗅觉感受器的细微结构上,利用双向凝胶电泳、质谱分析、聚合酶... 详细信息

蜜蜂已经进化出复杂精细的化学交流系统去调节他们错综复杂的社会互动,与气味检测相关的特殊蛋白质很可能在这种化学交流中起作用。气味接收过程主要发生在触角的一个被称作嗅觉感受器的细微结构上,利用双向凝胶电泳、质谱分析、聚合酶链式反应、生物信息学对性成熟雄蜂及觅食蜂（一组同日龄阶段被派到巢外执行任务的蜜蜂）的触角蛋白体进行比较。被鉴定出的61个差异表达蛋白在雄蜂触角上有67%高度表达,而在工蜂触角上仅有33%表达。工蜂触角上碳水化合物、能量代谢及分子转运蛋白强烈表达,这表明了工蜂对能量代谢及气味结合蛋白（与蜜蜂觅食活动、其他嗅觉反应相关）的强烈需求;而雄蜂触角上被高度上调的蛋白则与脂肪代谢、抗氧化及蛋白质折叠相关,这表明雄蜂在与蜂后交配识别时,性信息素检测与降解的重要性。在两组被改变的触角蛋白体上,碳水化合物代谢、能量生产及分子转运蛋白分别构成了80%的功能富集分析和45%的生物相互作用网络（BIN）的构建。这表明这两个蛋白质家族在性成熟雄蜂和觅食工蜂的触角嗅觉功能中起着至关重要的作用。本实验在转录水平上验证了几个生物相互作用网络中的关键节点蛋白。这是第一次对触角进行国际蛋白组学分析,揭示了两种蜜蜂的性别偏向蛋白质表达。这更说明了由于自然选择出现了不同的嗅觉功能,即嗅觉反应机制具有性别特异性。据我们所知。这一结果进一步为雄蜂及工蜂触角蛋白质的表达提供了更为深刻的见解,而且为之前的发现增添了重要信息。这也为今后对蜜蜂触角进行详细分析提供了新的角度。

关键词： honeybee drone worker antennae proteome sex olfaction

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 72-78页

作者： Y.P. Ma j. li j. Zhu L. Yang Y.G. liu Z.Y. li F. Zhao School of Metallurgic Engineering Xi＇an University of Architecture ＆ Technology Xi＇an 710055 China

The corrosion resistance of pure magnesium with surface alloying layer obtained by a solid diffusion alloying technique has been analyzed. To establish the optimum treatment time, the experiments were performed at 480℃ for different solid diffusion time （8, 16, and 24h）. The diffusion interaction effectiveness between Zn, Al mix powder and the sample surface, depending on the treatment time for diffusion at given temperatures, has an obvious influence on corrosion resistance and corrosion mechanism. Corrosion properties were studied using the constant immersion test （in 3.0% NaCl solution, temperature is （28±1）℃, and time is 96h）. Optical microscopy （OM） and EDS （energy dispersive spectrum） composition analysis were used to examine the cross-sectional microstructural characteristics of alloyed layer of treated samples. It is shown that in comparison with the untreated samples, the treated ones possess a better corrosion resistance. The Al5Mg11Zn4 phase, which formed as a continuous phase due to the diffusion of Al, Zn, and Mg elements and subsequent interaction on the outermost layer of diffusion alloying zones （especially the samples treated for 24h at 480℃）, was inert to the chloride solution compared with pure magnesium and acted as a corrosion barrier, and therefore the best corrosion resistance was obtained. This protective action of Al5Mg11Zn4 phase was found to change with its amount, which was controlled by the diffusion time at given temperature. It was concluded that the continuous Al5Mg11Zn4 phase （WP-zone） of the reacted layer in pure magnesium was beneficial from the point of view of corrosion resistance.

关键词： pure magnesium solid diffusion treatment time microstructure corrosion