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Lubrication Performance of Connecting-Rod and Main Bearing in Di erent Engine Operating Conditions

Chinese Journal of Mechanical Engineering 2019年第2期32卷 81-92页

作者： Jun Sun Biao li Shaoyu zhu Enming Miao Hu Wang xiaoyong Zhao Qin Teng School of Automotive and Transportation Engineering Hefei University of Technology School of Mechanical Engineering Hefei University of Technology School of Instrument Science and Opto-electronics Engineering Hefei University of Technology

Only the lubrication performance at rated engine operating condition was generally analyzed in current design and research of engine connecting-rod and main bearing. However, the actual engine(especially vehicle engine) does not always operate in rated operating condition and its operating condition changes constantly. In this paper, a fourstroke four-cylinder engine is taken as the studying object, the load and lubrication of connecting-rod and main bearing in di erent operating conditions are analyzed. The load of connecting-rod bearing is calculated by the dynamic calculation method, the loads of all main bearings are calculated by the whole crankshaft beam-element finite element method, and the lubrication performance of connecting-rod and main bearings are analyzed by the dynamic method. The results show that there are major di erences in the changes and numerical value at corresponding moment of the loads and lubrication performance of connecting-rod and main bearings in an engine operating cycle in di erent engine operating conditions; the most unfavorable case of the lubrication performance of connectingrod and main bearings may not take place in the rated engine operating condition. There are also major di erences between the lubrication performance of connecting-rod bearing and that of main bearing and between the lubrication performances of main bearings one another. Therefore, it will not be reasonable that the lubrication performance of a certain connecting-rod bearing or main bearing is analyzed in the design of the engine bearing. It is necessary to analyze simultaneously the lubrication performances of all bearings in di erent engine operating conditions.

关键词： Lubrication Connecting-rod bearing Main bearing Engine Operating condition

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Resistance and fitness costs in diamondback moths after selection using broflanilide, a novel meta-diamide insecticide

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Insect Science 2022年第1期29卷 188-198页

作者： Xi Sun Rui Wei linhong li Bin zhu Pei liang Xiwu Gao Department of Entomology China Agricultural UniversityBeijing100193China

The diamondback moth (DBM) Plutella xylostella (L.) (Lepidoptera: Plutellidae) is an insect pest found around the world that feeds on cruciferous crops. The DBM has become resistant to most insecticides in current use in the field. Broflanilide is a novel meta-diamide insecticide that binds to a new site on the γ-aminobutyric acid receptor and very efficiently protects against most pests in the order Lepidoptera, including DBM. In this study, the resistance of a laboratory-bred susceptible strain of DBM to broflanilide and the fitness costs posed by broflanilide to the DBM were evaluated. The DBM had no obvious resistance to broflanilide after 10 generations of selection. The realized heritability h2 was 0.033, suggesting a low risk of resistance developing in this strain. The F10 generation had no cross-resistance to the insecticides abamectin and endosulfan (which target the γ-aminobutyric acid receptor) and chlorantraniliprole (which targets a non-γ-aminobutyric acid receptor). The specific activities of important detoxification enzymes (cytochrome P450 monooxygenase, esterase, and glutathione S-transferase) were not obviously altered. However, the larval stage was prolonged and the adult stage was shortened significantly in F11 generation than the F0 generation. The total preoviposition period TPOP significantly prolonged 1.90 d in F11 generation. The fitness value Rf (0.93) was lower for the F11 generation than the F0 generation. The results indicated that long-term exposure to broflanilide exerts clear fitness costs in the DBM. This information will be useful in identifying reasonable broflanilide application guidelines for managing broflanilide resistance in the DBM.

关键词： broflanilide cross-resistance detoxifying enzymes fitness cost Plutella xylostella

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Visco-acoustic transmission waveform inversion of velocity structure in space-frequency domain

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Earthquake Science 2009年第1期22卷 45-52页

作者： Guihua Long xiaofan li Meigen Zhang Tong zhu Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

According to the least square criterion of minimizing the misfit between modeled and observed data, this paper provides a preconditioned gradient method to invert the visco-acoustic velocity structure on the basis of using sparse matrix LU factorization technique to directly solve the visco-acoustic wave forward problem in space-frequency domain. Numerical results obtained in an inclusion model inversion and a layered homogeneous model inversion demonstrate that different scale media have their own frequency responses, and the strategy of using low-frequency inverted result as the starting model in the high-frequency inversion can greatly reduce the non-tmiqueness of their solutions. It can also be observed in the experiments that the fast convergence of the algorithm can be achieved by using diagonal elements of Hessian matrix as the preconditioned operator, which fully incorporates the advantage of quadratic convergence of Gauss-Newton method.

关键词： visco-acoustic waveform inversion LU factorization preconditioned operator

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Recent Progress on Flexible Room-Temperature Gas Sensors Based on Metal Oxide Semiconductor

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Nano-Micro Letters 2022年第12期14卷 310-351页

作者： Lang-Xi Ou Meng-Yang liu li-Yuan zhu David Wei Zhang Hong-liang Lu State Key Laboratory of ASIC and System Shanghai Institute of Intelligent Electronics&SystemsSchool of MicroelectronicsFudan UniversityShanghai 200433People’s Republic of China Yiwu Research Institute of Fudan University Chengbei RoadYiwu City 322000ZhejiangPeople’s Republic of China

With the rapid development of the Internet of Things,there is a great demand for portable gas *** oxide semiconductors(MOS)are one of the most traditional and well-studied gas sensing materials and have been widely used to prepare various commercial gas ***,it is limited by high operating *** current research works are directed towards fabricating high-performance flexible room-temperature(FRT)gas sensors,which are effective in simplifying the structure of MOS-based sensors,reducing power consumption,and expanding the application of portable *** article presents the recent research progress of MOS-based FRT gas sensors in terms of sensing mechanism,performance,flexibility characteristics,and *** review comprehensively summarizes and discusses five types of MOS-based FRT gas sensors,including pristine MOS,noble metal nanoparticles modified MOS,organic polymers modified MOS,carbon-based materials(carbon nanotubes and graphene derivatives)modified MOS,and two-dimensional transition metal dichalcogenides materials modified *** effect of light-illuminated to improve gas sensing performance is further ***,the applications and future perspectives of FRT gas sensors are also discussed.

关键词： Metal oxide semiconductor Flexible gas sensor Room temperature Nanomaterials

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Shear-thinning behavior of the CaO–SiO2–CaF2–Si3N4 system mold flux and its practical application

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International Journal of Minerals,Metallurgy and Materials 2017年第10期24卷 1096-1103页

作者： Ying Xu Zhi-peng Yuan li-guang zhu Yi-hua Han Xing-juan Wang Hebei Provincial Key Laboratory of Inorganic Nonmetallic Materials College of Materials Science and Engineering North China University of Science and Technology Tangshan 063009 China Key Laboratory for Advanced Metallurgy Technology Hebei Provincial High-Quality Steel Continuous Casting Engineering Technology Research Center College of Metallurgy & Energy North China University of Science and Technology Tangshan 063009 China

Satisfying the mold-flux performance requirements for high-speed continuous casting necessitates the development of a new non-Newtonian-fluid mold flux with shear-thinning behavior, i.e., a mold flux whose viscosity is relatively high under lower shear rates and relatively low under higher shear rates. In this work, a mold flux that exhibits shear-thinning behavior was developed by adding different amounts of Si_3N_4 to the CaO–SiO_2–CaF_2 mold flux. The shear-thinning behavior was investigated using a rotational viscometer. In addition, the microstructure of the newly prepared slags was studied by high-temperature Raman spectroscopy and X-ray photoelectron spectroscopy. The results showed that the mechanism of shear-thinning was attributable to a temporary viscosity loss caused by the one-way shear stress, whereas the corresponding magnitude of shear-thinning was closely related to the degree of polymerization(DP). Finally, the non-Newtonian fluid mold flux was used for laboratory casting tests, which revealed that the mold flux could reduce slag entrapment and positively affect the continuous casting optimization.

关键词： mold flux viscosity shear-thinning behavior non-Newtonian fluid degree of polymerization

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Synthesis and Characterization of Easily Colored Meta-aramid Copolymer Containing Ether Bonds

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Chinese Journal of Polymer Science 2019年第3期37卷 227-234页

作者： Na li Xing-Ke Zhang Jun-Rong Yu Yan Wang Jing zhu Zu-Ming Hu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University

This work described the preparation of easily colored meta-aramid(PMIA) copolymers from m-phenylenediamine(MPD),isophthaloyl dichloride(IPC), and 3,4′-oxydianiline(3,4′-ODA) via solution polycondensation in N,N-dimethylacetamide(DMAc). The novel co-PMIAs were obtained in relatively high inherent viscosities ranging from 1.32 dL/g to 2.53 dL/g, which could be easily cast into flexible films with high transparence or spun into fibers. All the newly synthesized copolymers possessed excellent thermal stabilities even better than that of commercial PMIA, with 5% weight loss temperatures higher than 430 °C in nitrogen measured by TGA and glass transition temperature of 267–277 °C measured by DSC. The cast films exhibited good mechanical properties with a tensile strength up to107 MPa and a tensile modulus up to 2.2 GPa. The resultant PMIAs also showed good solubility and better dye ability for cationic dyes.

关键词： Copolymerized meta-aramid Solution polycondensation Dyeability

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Nickel-like Molybdenum and Niobium Soft X-Ray Lasing Driven by 200 ps Laser Pulses with 50 J of Energy

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Chinese Physics Letters 1999年第9期16卷 653-655页

作者： GU Yu-qiu li Ying-jun li Yu-tong CHUNYU Shu-tai YOU Yong-lu HUANG Wen-zhong HE Shao-tang HE Ying-ling LU li-zhu YUAN xiao-dong WEI xiao-feng ZHANG Chuan-fei ZHANG Jie National Laboratory of High Temperature and High Density Laser-Plasma Institute of Nuclear Physics and ChemistryChengdu 610003 Institute of Physics Chinese Academy of SciencesBeijing 100080

Intense lasing at 18.9 and 20.3nm in nickel-like molybdenum and niobium ions has been observed by using two 200ps laser pulses with total energy of 50 J at 1.053μm from XingGuang II laser *** gain coefficients were measured to be 1.6 and 1.5cm-1,*** shows the possibility of extending Ni-like x-ray lasing in low-Z elements and paves the way towards small scale x-ray lasers for applications at university laboratories.

关键词： laser lasing Pulse

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Template-free large-scale synthesis of g-C3N4 microtubes for enhanced visible light-driven photocatalytic H2 production

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Nano Research 2018年第6期11卷 3462-3468页

作者： Chao Zhou Run Shi Lu Shang li-zhu Wu Chen-Ho Tung Tierui Zhang Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

A template-free hydrothermal-assisted thermal polymerization method has been developed for the large-scale synthesis of one-dimensional （1D） graphitic carbon nitride （g-C3N4） microtubes. The g-C3N4 microtubes were obtained by simple thermal polymerization of melamine-cyanuric acid complex microrods under N2 atmosphere, which were synthesized by hydrothermal treatment of melamine solution at 180℃ for 24 h. The as-obtained g-C3N4 microtubes exhibited a large surface area and a unique one-dimensional tubular structure, which provided abundant active sites for proton reduction and also facilitated the electron transfer processes. As such, the g-C3N4 microtubes showed enhanced photocatalytic H2 production activity in lactic acid aqueous solutions under visible light irradiation （A 〉 420 nm）, which was - 3.1 times higher than that of bulk g-C3N4 prepared by direct thermal polymerization of the melamine precursor under the same calcination conditions.

关键词： graphitic carbon nitride(g-C3N4)microtubes photocatalytic water splitting visible light response

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Finding susceptible and protective interaction patterns in large-scale genetic association study

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Frontiers of Computer Science 2017年第3期11卷 541-554页

作者： Yuan li Yuhai ZHAO Guoren WANG xiaofeng zhu Xiang ZHANG Zhanghui WANG Jun PANG School of Computer Science and Engineering Northeastern University Shenyang 110819 China Department of Electronic Engineering and Computer Science Case Western Reserve University Cleveland OH 44106 USA Department of Epidemiology and Biostatistics Case Western Reserve University Cleveland OH 44106 USA

Interaction detection in large-scale genetic asso- ciation studies has attracted intensive research interest, since many diseases have complex traits. Various approaches have been developed for finding significant genetic interactions. In this article, we propose a novel framework SRMiner to detect interacting susceptible and protective genotype patterns. SR- Miner can discover not only probable combination of single nucleotide polymorphisms （SNPs） causing diseases but also the corresponding SNPs suppressing their pathogenic func- tions, which provides a better prospective to uncover the un- derlying relevance between genetic variants and complex dis- eases. We have performed extensive experiments on several real WeUcome Trust Case Control Consortium （WTCCC） datasets. We use the pathway-based and the protein-protein interaction （PPI） network-based evaluation methods to verify the discovered patterns. The results show that SRMiner successfully identifies many disease-related genes verified by the existing work. Furthermore, SRMiner can also infer some uncomfirmed but highly possible disease-related genes.

关键词： genetic association studies genotype pattern mining data mining bioinformatics

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Unicentric Castleman disease was misdiagnosed as pancreatic mass:A case report

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World Journal of Clinical Cases 2022年第4期10卷 1278-1285页

作者： Hong-Yan Zhai Xin-Yuan zhu Gui-Ming Zhou li zhu Dan-Dan Guo Hao Zhang Department of Ultrasound Tianjin Medical University General HospitalTianjin 300005China Department of Cardivascular Tianjin Medical University General HospitalTianjin 300005China Department of Cardivascular Surgery Tianjin Medical University General HospitalTianjin 300005China

BACKGROUND Castleman’s disease(CD)is a lymphatic proliferative disorder of unknown cause and is rarely seen *** has been divided into unicentric and multicentric *** CD(UCD)occurs as a solitary enlarged mass and mediastinal lymph nodes are the most common *** excision has proven to be curative for *** CD(MCD)appears as a systemic disease with peripheral *** had a poor response to surgery and monoclonal antibodies with rituximab have become a research *** SUMMARY A 44-year-old woman presented with a pancreatic mass during routine physical *** had no obvious symptoms,such as fever,abdominal pain,abdominal distension,or *** examination indicated a hypoechoic mass between the body of the pancreas,left lobe of the liver and *** had a clear boundary,irregular shape,uneven echo,and no obvious blood flow *** clarify the diagnosis,contrast-enhanced ultrasound examination was performed,which showed a benign pancreatic *** or solid pseudopapillary tumor was a possible *** patient underwent further contrast-enhanced computed tomography and contrastenhanced magnetic resonance imaging,which were suggestive of solid pseudopapillary tumor or neuroendocrine *** the examinations failed to give a definitive diagnosis,and the patient underwent *** final pathological and immunohistochemical results showed that the mass was *** This case highlights when lymphadenopathy is encountered clinically,CD should be considered and a biopsy should be performed.

关键词： Castleman’s disease Lymphadenopathy Unicentric Multicentric Contrastenhanced ultrasound Case report

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