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Insect Science 2015年第6期22卷 761-767页

作者： Hui Li kun-ling lang Hai-Bin Fu Chang-Peng Shen Fang-Hao Wan Dong Chu Key Lab of Integrated Crop Pest Management of Shandong Province College of Agronomy and Plant Protection Qingdao AgriculturalUniversity Qingdao Shandong Province China Shenyang Entry-Exit Inspection and Quarantine Bureau Shenyang China StateKey Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences(CAAS) Beijing China

The cotton mealybug, Phenacoccus solenopsis Tinsley, is a serious and invasive pest. At present, genetic resources for studying P. solenopsis are limited, and this negatively affects genetic research on the organism and, consequently, translational work to improve management of this pest. In the present study, expressed sequence tags （ESTs） were analyzed from a normalized complementary DNA library of/？. solenopsis. In addition, EST-derived microsatellite loci （also known as simple sequence repeats or SSRs） were isolated and characterized. A total of 1107 high-quality ESTs were acquired from the library. Clustering and assembly analysis resulted in 785 unigenes, which were classified functionally into 23 categories according to the Gene Ontology database. Seven EST-based SSR markers were developed in this study and are expected to be useful in characterizing how this invasive species was introduced, as well as providing insights into its genetic microevolution.

关键词： expressed sequence tags microsatellite marker normalized cDNA library Phenacoccus solenopsis

基于锚定PCR技术对10种重要农业害虫微卫星DNA位点的筛选及其特征分析

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生物安全学报 2014年第1期23卷 60-65页

作者：李慧郎坤玲沈长朋李洁陶云荔褚栋青岛农业大学农学与植物保护学院山东省植物病虫害综合防控重点实验室山东青岛266109

微卫星DNA广泛存在于真核和原核生物的基因组中，具有多态性丰富、易于检测等特点，在遗传图谱的构建、动植物遗传学育种等方面被广泛应用。利用5′锚定PCR技术对桃小食心虫、桃蛀螟、玉米螟、二点委夜蛾、花蓟马、黄胸蓟马、棕榈蓟马... 详细信息

微卫星DNA广泛存在于真核和原核生物的基因组中，具有多态性丰富、易于检测等特点，在遗传图谱的构建、动植物遗传学育种等方面被广泛应用。利用5′锚定PCR技术对桃小食心虫、桃蛀螟、玉米螟、二点委夜蛾、花蓟马、黄胸蓟马、棕榈蓟马、斑翅果蝇、稻水象甲、扶桑绵粉蚧10种重要农业害虫进行微卫星DNA筛选，并分析各个物种的微卫星DNA的特点。不同物种的阳性克隆率、微卫星比率、克隆效率和冗余率存在不同程度的差异；在核苷酸碱基数目上，主要为二核苷酸重复序列，占重复位点总数的93．2％～100％，三、四核苷酸重复位点较少。在二核苷酸重复位点中， CA/TG重复位点最为丰富，占重复位点总数的89．2％～100％。这与使用的锚定引物密切相关；10种害虫的微卫星DNA平均重复次数为6．7～8．9次，其中玉米螟具有最高的微卫星DNA重复次数（34次）；在序列类型上，完全型序列占上述害虫序列总数的91．0％～100％。5′锚定PCR技术能够快速挖掘害虫的微卫星DNA位点，本研究结果为这些害虫微卫星位点的进一步利用奠定了基础。

关键词：农业害虫微卫星 5′锚定PCR技术克隆特征分析

Hydrogen-assisted activation of N_(2)molecules on atomic steps of ZnSe nanorods

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Nano Research 2023年第5期16卷 6721-6727页

作者： kun Du Xiuyao lang Yuanyuan Yang Chuanqi Cheng Ning Lan Kangwen Qiu Jing Mao Weichao Wang Tao ling Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education Institute of New-EnergySchool of Materials Science and EngineeringTianjin UniversityTianjin 300072China Tianjin Key Laboratory of Photo-Electronic Thin Film Device and Technology College of Electronic Information and Optical Engineering Nankai UniversityTianjin 300071China College of Energy Engineering Huanghuai UniversityZhumadian 463000China

Electrochemical reduction reaction of nitrogen(NRR)offers a promising pathway to produce ammonia(NH_(3))from renewable ***,the development of such process has been hindered by the chemical inertness of N_(2).It is recently proposed that hydrogen species formed on the surface of electrocatalysts can greatly enhance ***,there is still a lack of atomiclevel connection between the hydrogenation behavior of electrocatalysts and their NRR ***,we report an atomistic understanding of the hydrogenation behavior of a highly twinned ZnSe(T-ZnSe)nanorod with a large density of surface atomic steps and the activation of N_(2)molecules adsorbed on its *** theoretical calculations and in situ infrared spectroscopic characterizations suggest that the atomic steps are essential for the hydrogenation of T-ZnSe,which greatly reduces its work function and efficiently activates adsorbed N_(2)***,the liquid-like and free water over T-ZnSe promotes its *** a result,T-ZnSe nanorods exhibit significantly enhanced Faradaic efficiency and NH3 production rate compared with the pristine ZnSe *** work paves a promising way for engineering electrocatalysts for green and sustainable NH3 production.

关键词： electrocatalytic nitrogen reduction reaction atomic steps work function ZnSe

Nanofriction characteristics of h-BN with electric field induced electrostatic interaction

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Friction 2021年第6期9卷 1492-1503页

作者： Kemeng YU kun ZOU Haojie lang Yitian PENG Shanghai Collaborative Innovation Center for High Performance Fiber Composites Donghua UniversityShanghai 201620China College of Mechanical Engineering Donghua UniversityShanghai 201620China Engineering Research Center of Advanced Textile Machinery Donghua UniversityShanghai 201620China

The nanofriction properties of hexagonal boron nitride(h-BN)are vital for its application as a substrate for graphene devices and solid lubricants in micro-and nano-electromechanical *** this work,the nanofriction characteristics of h-BN on Si/SiO_(2) substrates with a bias voltage are explored using a conductive atomic force microscopy(AFM)tip sliding on the h-BN surface under different substrate bias *** results show that the nanofriction on h-BN increases with an increase in the applied bias difference(V_(t–s))between the conductive tip and the *** nanofriction under negative V_(t–s) is larger than that under positive V_(t–s).The variation in nanofriction is relevant to the electrostatic interaction caused by the charging *** electrostatic force between opposite charges localized on the conductive tip and at the SiO2/Si interface increases with an increase in V_(t–s).Owing to the characteristics of p-type silicon,a positive V_(t–s) will first cause depletion of majority carriers,which results in a difference of nanofriction under positive and negative V_(t–s).Our findings provide an approach for manipulating the nanofriction of 2D insulating material surfaces through an applied electric field,and are helpful for designing a substrate for graphene devices.

关键词： nanofriction electrostatic interaction bias voltage h-BN atomic force microscopy

Novel Ag2S nanoparticles on reduced graphene oxide sheets as a super-efficient catalyst for the reduction of 4-nitrophenol

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Chinese Chemical Letters 2017年第2期28卷 417-421页

作者： Bin lang Hong-kun Yu College of Material Science and Engineering Fudan University Shanghai 200433 China

Here,Ag2S nanoparticles on reduced graphene oxide（Ag2S NPs/RGO） nanocomposites with relatively good distribution are synthesized for the first time by conversing Ag NPs/RGO to Ag2S NPs/RGO via a facile hydrothermal sulfurization *** an noval catalyst for the reduction of 4-nitrophenol（4-NP）,it only takes 5 min for Ag2S NPs/RGO to reduce 98% of 4-NP,and the rate constant of the composites is almost 13 times higher than that of Ag NPs/RGO *** high catalytic activity of Ag2S NPs/RGO can be attributed to the following three reasons：（1） Like metal complex catalysts,the Ag2S NPs is also rich with metal center Ag（δ^＋）,with pendant base S（δ） close to it,and thus the Ag and basic S function as the electron-acceptor and proton-acceptor centers,respectively,which facilitates the catalyst reaction;（2）RGO features the high adsorption ability toward 4-NP which provides a high concentration of 4-NP near the Ag2S NPs;and（3） electron transfer from RGO to Ag2S NPs,facilitating the uptake of electrons by 4-NP molecules.

关键词： Reduced graphene oxide Ag_2S nanoparticles Nanocomposites 4-Nitrophenol Catalytic activity

Design concept development of a variable magnetization motorwith improved efficiency and controllable stiffness for roboticapplications

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Science China(Technological Sciences) 2019年第1期62卷 39-46页

作者： BAI kun ZHU lang YUAN Mi LEE Kok-Meng State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Woodruff School of Mechanical Engineering Georgia Institute of Technology

A variable magnetization(VM) motor by incorporating magnets that can be flexibly configured with variable magnetization process is proposed to meet the emerging requirements on motor efficiency and actuator compliance in robotic applications. A generalized spin torque model is established which provides a relationship between the motor torque and two different types of motor inputs, the current inputs and the magnet magnetizations. Avariable magnetization process is proposed based on the study of the hysteresis properties of the magnetic materials and the design criteria for implementing the variable magnetization process with current pulses are established. The feasibility of the variable magnetization is validated with experimental data and the motor functions and performances are numerically demonstrated and evaluated. The results show that the VM motor can maintain high efficiency by switching between two actuation modes. Controllable stiffness at different equilibria can be also achieved with the VM motor with instantaneous magnetizing current pulses.

关键词： compliant actuators direct-drive motors variable stiffness motors variable magnetization motors

Integration of nanoindentation and finite element method for interpretable tensile properties:A crossscale calculation method of uneven joints

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Chinese Journal of Aeronautics 2023年第6期36卷 233-248页

作者： kun GAO Zhiying LIU Xiuli SHEN Lizhong lang Shaojing DONG School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Materials Science and Engineering University of TorontoTorontoON M5S 3E4Canada

Nanoindentation testing and its Reverse Analysis Method(RAM)show great potential in understanding the tensile properties of metallic alloys with various ***,the tensile properties of heterogeneous materials such as nickel-based superalloy welded joints have not been well interpreted by combining the microstructures and nanoindentation results,due to their diverse and complex microscopic zones,which throws shade on the properties of separated zones in the *** we demonstrated a new method of implanting nanoindentation results into Finite Element Method(FEM)and applied the method to the welded joints with the zones of various microstructure *** local properties are calculated by the nanoindentation data using RAM,and used as input of Finite Element(FE)simulation of an identical indentation process,to in turn verify the accuracy and reliability of the reverse *** simulation results reveal that the global mechanical behaviors,such as Young's modulus,yield strength and strain hardening exponent,are related to the local properties to a great ***,the global properties can be verified by simulation straight after experiments,taking consideration of local properties and dimension parameters of different *** is shown that the maximum error between calculation of RAM and testing is within 5.1%in different zones,and the errors of maximum indentation depth and residual depth obtained by FE simulation are less than 2.4%,which indicates that the method provides a reliable prediction of mechanical properties of superalloy welded joints.

关键词： Finite element method Nanoindentation Reverse analysis method Tensile properties Welded joints

A corrosion-reconstructed and stabilized economical Fe-based catalyst for oxygen evolution

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Nano Research 2023年第2期16卷 2224-2229页

作者： Zhiquan lang Guang-ling Song Pengpeng Wu Dajiang Zheng Center for Marine Materials Corrosion and Protection Xiamen UniversityXiamen 361005China Department of Ocean Science and Engineering Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen UniversityXiamen 361005China The University of Queensland St.LuciaQLD 4072Australia

The anode activity can to a great degree limit the cathodic hydrogen evolution efficiency in an electrolyte ***,cost-efficient electrocatalysts with good water oxidation performance and stability are highly desired in widespread implementation of the hydrogen production from water *** paper proposes a facile corrosion-reconstruction strategy to transform Fe surface into a Fe-Co hydroxide layer to improve the oxygen evolution *** as-prepared catalyst was measured to have an over-potentential as low as 320 mV at 100 mA·cm^(−2),and its stability even exceeded 600 *** and Raman spectroscopy analyses indicated that the catalyst experienced chemical changes from hydroxides to oxyhydroxides and Co^(2+)to Co^(3+)during oxygen evolution reaction(OER).The corrosion-reconstruction is not only an economical method to synthesize a highly efficient,stable and durable Fe-based catalysts,it also converses the detrimental corrosion into a beneficial catalyst fabrication process.

关键词： oxygen evolution reaction electrocatalyst corrosion stability

Weighted Least Squares Method for the Accelerated Failure Time Model with Auxiliary Covariates

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Acta Mathematica Sinica,English Series 2019年第7期35卷 1163-1178页

作者： ling Hui JIN Yan Yan LIU lang WU School of Mathematics and Statistics Wuhan University Wuhan 430072 P. R. China City College Wuhan University of Science and Technology Wuhan 430083 P. R. China Department of Statistics University of British Columbia Vancouver Canada

This paper deals with the analysis of accelerated failure time model when the primary covariate is subject to missing. We assume that the true covariate is measured precisely on a randomly chosen validation set, whereas auxiliary information for primary covariate is available to all study subjects. The asymptotic properties for the proposed estimator are developed and the simulation studies show that the efficiency gain is remarkable compared to the method using only the validation sample. A real example is also provided as an illustration.

关键词： Survival analysis accelerated failure time model auxiliary covariates validation sample weighted least squares estimation

Assessing the energy release characteristics during the middle detonation reaction stage of aluminized explosives

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Defence Technology（防务技术） 2024年第3期33卷 270-277页

作者： kun Yang lang Chen Danyang Liu Bin Zhang Jianying Lu Junying Wu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

Afterburning behind the detonation front of an aluminized explosive releases energy on the millisecond timescale,which prolong the release of detonation energy and the energy release at different stages also shows significant ***,at present,there are few effective methods for evaluating the energy release characteristics of the middle reaction stage of such explosives,which can have a duration of tens to hundreds of *** present work demonstrates an approach to assessing the midstage of an aluminized explosive detonation based on a water push test employing a high degree of *** this method,the explosive is contained in a steel cylinder having one end closed that is installed at the bottom of a transparent water *** detonation,the gaseous products expand in one direction while forcing water ahead of *** resulting underwater shock wave and the interface between the gas phase products and the water are tracked using an ultra-high-speed framing and streak *** shock wave velocity in water and the expansion work performed by the gaseous detonation products were calculated to assess the energy release characteristics of aluminized explosives such as CL-20 and RDX in the middle stage of the detonation *** the middle stage of the detonation process of these aluminized explosives,the aluminum reaction reduced the attenuation of shock waves and increased the work performed by gas phase products.A higher aluminum content increased the energy output while the presence of oxidants slowed the energy release *** work demonstrates an effective means of evaluating the performance of aluminized explosives.

关键词： Aluminized explosive Non-ideal detonation Water push test Energy release