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Effect of Addition of Polytetrafluoroethylene (PTFE) and Silicon Carbide (SiC) on Properties of Electroless Nickel Alloy Coatings

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材料热处理学报 2004年第05B期25卷 1102-1105页

作者： wuyu-cheng huxiao-ye wangwen.fang huangxin-min FacultyofMaterialsScienceandEngineering HefeiUniversityofTechnology230009HefeiP.R.China

Electroless nickel (copper)-phosphorus-silicon carbide (SiC)-polytetrafluoroethylene (PTFE) composite coatings were prepared by adding SiC and PTFE into electroless nickel (copper)-phosphorus alloy baths. The effects of addition of SiC and PTFE on depositing rate, microhardness, wear resistance and anti-friction of the resulted composite coatings were studied. The results indicated that electroless nickel (copper)-phosphorus alloy coatings were greatly improved in depositing rate, microhardness, wear resistance and antifriction by co-deposited proper amount of SiC and PTFE.

关键词：非电解淀积聚四氟乙烯碳化硅镍合金

Enhanced thermal conductivity and mechanical properties of 2D C_(f)/SiC composites modified by in-situ grown carbon nanotubes

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Journal of Advanced Ceramics 2024年第1期13卷 19-33页

作者： Changhui Niu Qing Zhang Laifei cheng fang ye Litong Zhang min Huang Tao Yang Science and Technology on Thermostructure Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China Civil Aviation Department Zhejiang Institute of CommunicationsHangzhou 311112China Zhejiang Provincial Key Laboratory for Cutting Tools Taizhou UniversityTaizhou 318000China

In this work,the effects of carbon nanotubes(CNTs)on the microstructure evolution,thermal conductivity,and mechanical properties of C_(f)/SiC composites during chemical vapor infiltration(CVI)densification were investigated in *** with composites without CNTs,the thermal conductivity,flexural strength,flexural modulus,fracture toughness,interfacial shear strength,and proportional limit stress of specimens with CNTs of 4.94 wt%were improved by 117%,21.8%,67.4%,10.3%,36.4%,and 71.1%,*** improvement was attributed to the role of CNTs in the division of inter-layer pores,which provided abundant vapor growth sites for the ceramic matrix and promoted densification of the whole *** addition,the high thermal conductivity network formed by the overlap of CNTs and the rivet strengthening effect of CNTs were beneficial for synergistic improvement of thermal conductivity and mechanical properties of the ***,this study has practical significance for the development of thermal protection composite components with enhanced thermal conductivity and mechanical characteristics.

关键词： ceramic−matrix composites carbon nanotubes microstructure thermal conductivity mechanical properties

3D printing“wire-on-sphere”hierarchical SiC nanowires/SiC whiskers foam for efficient high-temperature electromagnetic wave absorption

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Journal of Materials Science & Technology 2022年第14期109卷 94-104页

作者： Xinyuan Lv fang ye Laifei cheng Litong Zhang Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China

Electromagnetic wave absorption(EWA)materials for use in extreme environments are of great ***,SiC nanowires/SiC whiskers(SiC_(nw)/SiC_(w))foam with unique“wire-on-sphere”hierarchical structure was developed for efficient high-temperature ***_(w)were assembled to porous SiC_(w)spheres via spray drying and then SiC_(w)spheres were 3D printed to SiC_(w)*** catalyst-free precursor infiltration pyrolysis process was first developed to ensure that SiCnwcan intentionally grow in situ on the surface of SiC_(w)spheres,thereby achieving“wire-on-sphere”hierarchical structure *** room-temperature,the maximum electromagnetic wave effective absorption bandwidth(EAB_(max))and minimum electromagnetic wave reflection coefficient(RC_(min))of SiC_(nw)/SiC_(w)foam can reach 4 GHz and-57 dB,***600℃,the EAB_(max)and RC_(min) were 3 GHz and-15 dB,***,even oxidized at 1000-1500℃,SiC_(nw)/SiC_(w)foam can still retain EAB_(max)ranging from 2.7 to 3.9 GHz and RC_(min)ranging from-16 dB to-64 dB,because the formation of SiO_(2)layer with appropriate thickness can boost interfacial polarization and regulate impedance *** SiC_(nw)/SiC_(w)foam also shows the flexural strength as high as 17.05 *** results demonstrate that the SiC nw/SiC_(w)foam is a promising EWA material for applications of harsh *** the material-independent“wire-on-sphere”hierarchical structure and its novel preparation process should find the widespread use in the design and fabrication of high-efficiency EWA micro-nano materials.

关键词： “wire-on-sphere”hierarchical structure SiC nanowires SiC whiskers 3D printing High-temperature electromagnetic wave absorption

Monitoring impact of mefenacet treatment on soil microbial communities by PCR-DGGE fingerprinting and conventional testing procedures

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Journal of Environmental Sciences 2006年第2期18卷 373-378页

作者： ye Yang-fang min Hang LU Zhen-mei College of Life Science and Biotechnology Ningbo University Ningbo 315211 China College of Life Science Zhejiang University Hangzhou 310029 China

The effect of acetanilide herbicide mefenacet on soil microbial communities was studied using paddy soil samples with different short-term treatments. The culturable bacteria （plate counts）, dehydrogenase activity and changes in community structure （denaturing gradient gel electrophoresis （DGGE） analysis） were used for biological community assessments. Mefenacet was a significant stimulus to cultural aerobic bacteria and dehydrogenase activity while Sphingobacterium multivorum Y1, a bacterium efficiently degrading the mefenacet, only induced the increasing colony-forming unit （CFU） of bacteria but little effect on dehydrogenase activity during the whole experiment. The degree of similarity between the 16S rDNA profiles of the communities was quantified by numerically analyzing the DGGE band patterns. Similarity dendrograms showed that the microbial community structures of the mefenacet-treated and non-treated soils were not significantly different. But supplement of S. multivorum Y1 could increase the diversity of the microbial community in the mefenacet-polluted paddy soil. This work is a new attempt to apply the S. multivorum Y1 for remediation of the mefenacet-polluted environments.

关键词： denaturing gradient gel electrophoresis(DGGE) soil microbial diversity mefenacet dehydrogenase

Udwadia–Kalaba Equation for Constrained Mechanical Systems:Formulation and Applications

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Chinese Journal of Mechanical Engineering 2018年第6期31卷 11-24页

作者： Xiao-min Zhao ye-Hwa Chen Han Zhao fang-fang Dong School of Automotive and Transportation Engineering Hefei University of TechnologyHefei 230009China The George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta 30332USA School of Mechanical Engineering Hefei University of TechnologyHefei 230009China

There are many achievements in the field of analytical mechanics, such as Lagrange Equation, Hamilton’s Principle, Kane’s Equation. Compared to Newton–Euler mechanics, analytical mechanics have a wider range of applications and the formulation procedures are more mathematical. However, all existing methods of analytical mechanics were proposed based on some auxiliary variables. In this review, a novel analytical mechanics approach without the aid of Lagrange’s multiplier, projection, or any quasi or auxiliary variables is introduced for the central problem of mechanical systems. Since this approach was firstly proposed by Udwadia and Kalaba, it was called Udwadia–Kalaba Equation. It is a representation for the explicit expression of the equations of motion for constrained mechanical systems. It can be derived via the Gauss’ s principle, d’Alembert’s principle or extended d’Alembert’s principle. It is applicable to both holonomic and nonholonomic equality constraints, as long as they are linear with respect to the accelerations or reducible to be that form. As a result, the Udwadia–Kalaba Equation can be applied to a very broad class of mechani?cal systems. This review starts with introducing the background by a brief review of the history of mechanics. After that, the formulation procedure of Udwadia–Kalaba Equation is given. Furthermore, the comparisons of Udwadia–Kalaba Equation with Newton–Euler Equation, Lagrange Equation and Kane’s Equation are made, respectively. At last, three di erent types of examples are given for demonstrations.

关键词： Udwadia–Kalaba Equation Mechanical system Constraint Moore–Penrose inverse

APPLICATIONS OF CFD TECHNIQUE IN THE DESIGN AND FLOW ANALYSIS OF IMPLANTABLE AXIAL FLOW BLOOD PUMP

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Journal of Hydrodynamics 2010年第4期22卷 518-525页

作者： FAN Hui-min HONG fang-wen ZHANG Guo-ping ye Liang LIU Zhong-min Shanghai East Hospital Affiliated to Tongji University Shanghai 200120 China China Ship Scientific Research Center Wuxi 214082 China

Based on established numerical methods and hydrodynamic performance testing facilities,CFD technique are applied to improve the design of the implantable axial flow blood pump and the flow analysis.（1） Applying brushless machine magnet steel,reducing its thickness while increasing the length,the flow channel＇s cross-section is increased,with no space connection between the large and the small rotators,and with a cone transition segment from the bearing to the principal axis,the flow is made *** rotating speed is lowered by 1000 rpm-1200 rpm under the same flow rate and pressure head,and thus the hemolysis can be avoided.（2） Different outlet stator guiding vanes are selected for the same blood pump for analyses of hydrodynamic performances and flow *** excellent design not only can regulate the rotating flow field into an axial one,reduce the circulation loss and improve the pump efficiency,but also can avoid backflow,vortex and secondary flow at the pump outlet,and thus the thrombus can be prevented.（3） The calf live tests show that some residual clots exist at the inner wall of the outlet connection bends,which are analyzed and explained by CFD techniques and the corresponding improvements are *** results are verified by hydrodynamic performance tests and PIV flow field tests,and consistent conclusions are obtained.

关键词： axial flow blood pump CFD PIV

Statistical properties of random clique networks

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Frontiers of physics 2017年第5期12卷 251-257页

作者： Yi-min Ding Jun Meng Jing-fang Fan fang-Fu ye Xiao-Song Chen Faculty of Physics and Electronics Hubei University Wuhan 430062 China CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences P.O. Box 2735 Beijing 100190 China Beijing National Laboratory for Condensed Matter Physics CAS Key Laboratory of Soft Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China

In this paper, a random clique network model to mimic the large clustering coefficient and the modular structure that exist in many real complex networks, such as social networks, artificial networks, and protein interaction networks, is introduced by combining the random selection rule of the ErdSs and Rényi （ER） model and the concept of cliques. We find that random clique networks having a small average degree differ from the ER network in that they have a large clustering coefficient and a power law clustering spectrum, while networks having a high average degree have similar properties as the ER model. In addition, we find that the relation between the clustering coefficient and the average degree shows a non-monotonic behavior and that the degree distributions can be fit by multiple Poisson curves; we explain the origin of such novel behaviors and degree distributions.

关键词： complex networks random clique networks motifs communicability

A Novel Self-Synchronization Scheme Based on Cross Gain Modulation and Self-Frequency Shift in an SOA

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The Journal of China Universities of Posts and Telecommunications 2006年第1期13卷 67-70,83页

作者： ye Xiao-hua ZHANG fang-di ZHANG min ZHANG Rui ye Pei-da Key Laboratory of Optical Communication and Lightwave Technologies Beijing University of Po~ts and Telecommunications Beijing 100876 P.R. China

This paper presents a novel self-synchronization scheme utilizing a semiconductor optical amplifier and an optical band-pass filter. Implemented using cross gain modulation and self frequency shift, the proposed scheme has a simple structure that does not need any special marker pulses. With proper tuning of semiconductor optical amplifier and optical band-pass filter parameters and delay time of the control pulse, we, through simulation, obtain a synchronization clock with the intensity contrast ratio of more than 20 dB from RZ pseudorandom bit sequence at different operation speeds.

关键词： optical packet networks self-synchronization SOA FS CR

Hepatoid adenocarcinoma of the stomach: A report of three cases

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World Journal of Gastroenterology 2013年第27期19卷 4437-4442页

作者： min-Feng ye Feng Tao fang Liu Ai-Jing Sun Department of Gastrointestinal Surgery Shaoxing People's Hospital Shaoxing Hospital of Zhejiang University Department of Pathology Shaoxing People's Hospital

Hepatoid adenocarcinoma of the stomach (HAS) is a rare form of gastric cancer that has unique clinicopathological features and an extremely poor prognosis. Here, we report on three patients with suspected gastric cancer who were referred to our hospital. Gastrointestinal fiberscopy on the three patients revealed two lesions in the antrum and a third lesion in the gastroesophageal junction. The alpha fetoprotein (AFP) serum levels were markedly elevated in all cases. At the time of diagnosis, two cases were advanced stages with lymph nodes and/or liver metastases. Two patients underwent exploratory laparotomy. A total gastrectomy was performed on the operable lesion, and an expanded gastrectomy was completed in the case with hepatic metastases. Histopathological analysis revealed that the tumors displayed two pathological changes:hepatoid-like foci and adenocarcinomatous. Furthermore, the tumor cells were immunohistochemically positive for AFP, alpha-1 antitrypsin, and alpha-1 antichymotrypsin. All three patients received chemotherapy. The follow-up duration ranged from 8-36 mo. Our experience and previous published studies have suggested that HAS is an aggressive type of adenocarcinoma. However, radical surgery and chemotherapy may positively impact clinical outcomes.

关键词： Hepatic adenocarcinoma Gastric cancer Alpha fetoprotein Prognosis Stomach