检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

钢桁架屈曲分析研究

建筑技术 2024年第15期55卷 1796-1800页

作者：姚远陈亮陈智星彭宇中国建筑设计研究院有限公司北京100044

以某钢桁架结构为主要研究对象,借助有限元软件,进行了结构选型和建模,对钢桁架结构屈曲问题和结构优化设计开展了研究分析,结果表明:侧向钢桁架邻近跨中的部位为结构最薄弱处,在外界荷载作用下,该区域易发生局部失稳;考虑初始缺陷的非... 详细信息

以某钢桁架结构为主要研究对象,借助有限元软件,进行了结构选型和建模,对钢桁架结构屈曲问题和结构优化设计开展了研究分析,结果表明:侧向钢桁架邻近跨中的部位为结构最薄弱处,在外界荷载作用下,该区域易发生局部失稳;考虑初始缺陷的非线性屈曲分析相较于线性屈曲分析临界屈曲荷载系数明显降低,降低幅度在8.1%~39.1%;通过正交实验发现杆系的截面宽度对临界屈曲荷载系数的影响最大,截面高度和厚度的影响次之;利用非线性回归,得到了显著因素对临界屈曲荷载系数的预测公式。

关键词：钢桁架屈曲分析优化设计有限元分析

A 3D-printed microfluidic gradient concentration chip for rapid antibiotic-susceptibility testing

在线全文

学校读者我要写书评

暂无评论

Bio-Design and Manufacturing 2022年第1期5卷 210-219页

作者： Huilin Zhang yuan yao Yue Hui Lu Zhang Nanjia Zhou Feng Ju College of Environmental&Resource Sciences Zhejiang UniversityHangzhou 310058China Key Laboratory of Coastal Environment and Resources of Zhejiang Province School of EngineeringWestlake UniversityHangzhou 310024China Institute of Advanced Technology Westlake Institute for Advanced StudyHangzhou 310024China Key Laboratory of 3D Micro/Nano Fabrication and Characterization of Zhejiang Province Hangzhou 310024China

The rise of antibiotic resistance as one of the most serious global public health threats has necessitated the timely clinical diagnosis and precise treatment of deadly bacterial *** identify which types and doses of antibiotics remain effective for fighting against multi-drug-resistant pathogens,the development of rapid and accurate antibiotic-susceptibility testing(AST)is of primary *** methods for AST in well-plate formats with disk diffusion or broth dilution are both labor-intensive and operationally *** microfluidic chip provides a versatile tool for evaluating bacterial AST and resistant *** this paper,we develop an operationally simple,3D-printed microfluidic chip for AST which automatically deploys antibiotic concentration gradients and fluorescence intensity-based reporting to ideally reduce the report time for AST to within 5 *** harnessing a commercially available,digital light processing(DLP)3D printing method that offers a rapid,high-precision microfluidic chip-manufacturing capability,we design and realize the accurate generation of on-chip antibiotic concentration gradients based on flow resistance and diffusion *** further demonstrate the employment of the microfluidic chip for the AST of *** to representative clinical antibiotics of three classes:ampicillin,chloramphenicol,and *** determined minimum inhibitory concentration values are comparable to those reported by conventional well-plate *** proposed method demonstrates a promising approach for realizing robust,convenient,and automatable AST of clinical bacterial pathogens.

关键词： Microfluidics Gradient concentration chip Digital light processing Antibiotic-susceptibility test Bacteria

High-Gain Dual Circularly Polarized Antenna for Air-to-Ground Wireless Link

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2022年第3期31卷 555-561页

作者： JIANG Hang yao yuan XIU Tao CHENG Xiaohe YU Junsheng CHEN Xiaodong School of Electronic Engineering Beijing University of Posts and Telecommunications School of Electronic Engineering and Computer Science Queen Mary University of London

This paper presents an E-band reflector antenna fed by dual circularly polarized feed system. Axial displaced ellipse reflector is adopted for high gain and low blockage mechanisms. The feed system mainly composed of orthomode transducer, iris polarizer and horn antenna, and possesses dual circular polarization. The orthomode transducer offers high isolation performance in broadband by double symmetry and the iris polarizer achieves phase shift by introducing discontinuities. In addition, the ridge and iris in the feed are optimized to be wide enough to fabricate and maintain good mechanical properties in higher frequency band. The entire antenna is simulated and fabricated. The measured gain of 45 ± 1.2 d Bi corresponds to about 52% efficiency. The measured results of reflection coefficients less than-18 d B, isolation over 27 d B, axial-ratio value less than 2.3 d B are achieved from 71 to 86 GHz.

关键词： Dual circularly polarized Reflector antenna Feed system

A Wideband E-Plane Crossover Coupler for Terahertz Applications

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

China Communications 2021年第5期18卷 245-254页

作者： Xiaohe Cheng Zhiyan Liu yuan yao Junsheng Yu Xiaodong Chen Beijing Key Laboratory of Work Safety Intelligent Monitoring School of Electronic EngineeringBeijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering and Computer Science Queen Mary University of LondonLondon E14NSU.K.

In this paper,a new approach to design terahertz(THz)E-plane crossover coupler is *** cascading two symmetrical septum polarizers,a simple structure with wide operating bandwidth and high isolation performance is *** working principle is explained by operating waveguide *** simplify the optimization process,the scattering matrix(S-matrix)of the crossover is *** prototypes loaded and unloaded electromagnetic band gap(EBG)are fabricated and *** electrical contact problem at assembly plane is eliminated by the prototype loaded EBG.A measured bandwidth of 17.3%from 92.5 to 110 GHz for reflection and isolation coefficients-2 dB is achieved.

关键词： butler matrix crossover coupler high isolation multi-beam THz

In situ induced cation-vacancies in metal sulfides as dynamic electrocatalyst accelerating polysulfides conversion for Li-S battery

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第12期75卷 74-82,I0003页

作者： Rongrong Li Hao Sun Caiyun Chang yuan yao Xiong Pu Wenjie Mai Siyuan Laboratory Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy MaterialsDepartment of PhysicsJinan UniversityGuangzhou 510632GuangdongChina CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-Nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China State Key Laboratory of Power Transmission Equipment and System Security and New Technology School of Electrical EngineeringChongqing UniversityChongqing 400044China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Cation vacancy engineering is considered to be one of the effective methods to solve the issues of shuttling and sluggish redox kinetics of Li PSs owing to the intrinsic tunability of electronic ***,cation vacancies are few studied in the Li-S realm due to their complex and rigid preparation *** this work,one-step pyrolysis is reported to in situ introduce Fe-vacancies into iron sulfide(Fe_(0.96)S)as a sulfur *** this host structure,Fe_(0.96)S is first employed as an adsorbent and catalyst in Li-S *** the carbonization process,a tight contact structure of Fe_(0.96)S crystal and carbon network(Fe_(0.96)S@C)is in situ constructed,and the carbon layer as a conductor provides smooth electrons transfer pathways for redox ***,due to the introduction of Fe-vacancies in Fe S crystal,the adsorption capability and catalytic effect for Li PSs have been substantially ***,the presence of Fe_(0.96)S crystal favors the mobility of electron and diffusion of Li+,which is revealed by the experiments and theoretical *** synergy respective advantages effect of Fe_(0.96)S and carbon,the Fe_(0.96)S@C-S cathode delivers high-rate capability at 5.0 C and stable long-life *** under a high sulfur loading of 3.5 mg/cm^(2),the durable cyclic stability is still exhibited with the capacity retention of 93%over 400 cycles at 1.0 C,and the coulombic efficiency is≥98%.Noting that this strategy greatly simplifies the synthetic process of currently known cation-vacancy materials and furnishes a universal mentality for designing both divinable and astonishing new cation-vacancy materials.

关键词： Cation vacancy Fe_(0.96)S@C structure Catalytic conversion Lithium-sulfur battery

A new trick on an old support: Zr in situ defects-created carbon nitride for efficient electrochemical nitrogen fixation

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2021年第2期30卷 109-115,I0005页

作者： Wenwen Lin Siyu yao Hao Chen Shenglai Li Yang Xia yuan yao Jing Li Dangguo Cheng Jie Fu Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina Institute of Zhejiang University-Quzhou Quzhou 324000ZhejiangChina College of Chemistry and Materials Science Shanghai Normal UniversityShanghai 200234China

Electrochemical nitrogen reduction reaction(NRR) to produce ammonia under ambient conditions is considered as a promising approach to tackle the energy-intensive Haber-Bosch process,but the low Faradaic efficiency and yield of NH_3 are still a ***,a carbon-vacancies enriched mesoporous g-C_3 N_4 is developed by an in situ Zr doping *** in situ mesoporous-forming mechanism is deeply understood by TPSR to reveal the functions of Zr dopant that pulls C from the precursor of C_3 N_4,resulting the formation of homogeneous mesopores with about 57% of the one C-defective s-triazine ring in C_3 N_*** to the defect sites obtained in metal doping synthesis,the RuAu bimetallic supported catalyst(RuAu_3/0.3 Zr-C_3 N_4) exhibits effective NRR performance with a Faraday efficiency of 11.54% and an NH_3 yield of 5.28 μg h^(-1) mg_(cat) ^(-1).at-0.1 V(RHE),which is nearly 10 times higher than that of RuAu_3/C_3 N_4 *** work proposes a simple and template-free preparation method for the high defect density mesoporous C_3 N_4,and provides new possibilities of a wide application of mesopore g-C3 N4.

关键词： Graphitic carbon nitride Mesoporous Carbon defects Electrochemical Nitrogen fixation

Node Search Contributions Based Long-Term Follow-Up Specific Individual Searching Model

在线全文

学校读者我要写书评

暂无评论

清华大学学报:自然科学版(英文版) 2023年第4期28卷 729-742页

作者： Yayong Shi Fei Chang Yetao Sun Guangcheng Yang Rui Wang yuan yao School of Computer and Communication Engineering University of Science and Technology BeijingBeijing 100183China Institute for Hospital Management Research Chinese PLA General HospitalBeijing 100853China

In this paper,we introduce a long-term follow-up specific individual searching(SIS)*** model introduces the concept of node search contributions by considering the characteristics of the network structure.A node search contribution indicates the ability of a certain node to correctly guide the search path and successfully complete an *** influencing factors of node search contributions have three components:the individual influence index,attribute similarity,and node search *** the basis of node search contributions and the PeopleRank idea,this paper proposes an SIS model based on node search contribution values and conducts comparison experiments with several mainstream SIS algorithms in three aspects:the search failure rate,the minimum number of search hops,and the search *** experimental results verify the advanced nature and operability of the model proposed in this paper,which presents theoretical and practical significance to the quantitative study of the SIS process.

关键词： specific individual search complex networks propagation dynamics long-term follow-up

Electrochemical determination of quercetin by self-assembled platinum nanoparticles/poly(hydroxymethylated-3,4-ethylenedioxylthiophene) nanocomposite modified glassy carbon electrode

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2014年第4期25卷 505-510页

作者： yuan-yuan yao Long Zhang Zi-Fei Wang Jing-Kun Xu Yang-Ping Wen Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal University College of Science Jiangxi Agricultural University

A simple and sensitive platinum nanoparticles/poly（hydroxymethylated-3,4-ethylenedioxylthiophene） nanocomposite （PtNPs/PEDOT-MeOH） modified glassy carbon electrode （GCE） was successfully developed for the electrochemical determination of quercetin. Scanning electron microscopy and energy dispersive X-ray spectroscopy results indicated that the PtNPs were inserted into the PEDOT- MeOH layer. Compared with the bare GCE and poly（3,4-ethylenedioxythiophene）（PEDOT） electrodes, the PtNPs/PEDOT-MeOH/GCE modified electrode exhibited a higher electrocatalytic ability toward the oxidation of quercetin due to the synergic effects of the electrocatalytic activity and strong adsorption ability of PtNPs together with the good water solubility and high conductivity of PEDOT-MeOH. The electrochemical sensor can be applied to the quantification of quercetin with a linear range covering 0.04-91μmol L-1 and a low detection limit of 5.2 nmol L-1. Furthermore, the modified electrode also exhibited good reoroducibilitv and long-term stability, as well as high selectivity.

关键词： Poly( 3 4-ethylenedioxylthiophene methanol) Platinum nanoparticles Electropolymerization Differential pulse voltammetryQuercetin

Analysis of Optimal Portfolio with Different Utility Function

在线全文

学校读者我要写书评

暂无评论

Chinese Quarterly Journal of Mathematics 2006年第1期21卷 124-128页

作者： yao yuan SHI Ben-shan School of Economics and Management Southwest Jiaotong University Chengdu 610031 China School of Business Administration Henan University Kaifeng 475001 China

The question of optimal portfolio is that finds the trading strategy satisfying the maximal expected utility function subject to some constraints. There is the optimal trading strategy under the risk neutral probability measure （martingale measure） if and only if there is no-arbitrage opportunity in the market. This paper argues the optimal wealth and the optimal value of expected utility with different utility function.

关键词： expected utility function optimization portfolio risk neutral probability