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Journal of Materials Science & Technology 2018年第10期34卷 1835-1842页

作者： P.f. wang Z. Han Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

A gradient nano-grained （GNG） surface layer was fabricated on an AIS1316L stainless steel （SS） by using the surface mechanical rolling treatment （SMRT）. Reciprocating dry and oil-lubricated sliding tests of the GNG 316L SS in air at room temperature were conducted in comparison with the coarse-grained （CG） counterpart. Worn surface morphologies and subsurface microstructures were investigated for both 316L SS samples. 316L SS with a GNG surface layer shows a significantly improved wear resistance, especially under oil-lubricated condition. The notably wear resistance enhancement of the GNG 316L SS is attributed to the GNG surface layer with high strain accommodation ability and high hardness, which can reduce the wear volume in the running-in stage effectively.

关键词： Austenitic stainless steel Gradient nano-grained surface layer friction and wear Running-in

Modification Design Method for an Enveloping Hourglass Worm Gear with Consideration of Machining and Misalignment Errors

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Chinese Journal of Mechanical Engineering 2013年第5期26卷 948-956页

作者： DENG Xingqiao wang Jinge HORSTEMEYER Mark f School of Mechanical Engineering and Automation Xihua University Center for Advanced Vehicular Systems Mississippi State University

The influences of machining and misalignment errors play a very critical role in the performance of the anti-backlash double-roller enveloping hourglass worm gear(ADEHWG).However,a corresponding efficient method for eliminating or reducing these errors on the tooth profile of the ADEHWG is seldom *** gear engagement equation and tooth profile equation for considering six different errors that could arise from the machining and gear misalignment are derived from the theories of differential geometry and gear ***,the tooth contact analysis(TCA) is used to systematically investigate the influence of the machining and misalignment errors on the contact curves and the tooth profile by means of numerical analysis and three-dimensional solid *** research results show that vertical angular misalignment of the worm wheel(Δβ) has the strongest influences while the tooth angle error(Δα) has the weakest influences on the contact curves and the tooth profile.A novel efficient approach is proposed and used to minimize the effect of the errors in manufacturing by changing the radius of the grinding wheel and the approaching point of *** results from the TCA and the experiment demonstrate that this tooth profile design modification method can indeed reduce the machining and misalignment *** modification design method is helpful in understanding the manufacturing technology of the ADEHWG.

关键词： worm gears tooth contact analysis machining and misalignment errors tooth profile errors modification method

Enhanced Mechanical Properties of friction Stir Welded 5083Al-H19 Joints with Additional Water Cooling

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Journal of Materials Science & Technology 2017年第9期33卷 1009-1014页

作者： B.B.wang f.f.Chen f.Liu W.G.wang P.Xue Z.Y.Ma School of Mechanical Engineering Liaoning Shihua University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

3-mm-thick 5083Al-H19 rolled plates were friction stir welded(fSW) at tool rotation rates of 800 and200 rpm with and without additional water cooling. With decreasing the rotation rate and applying water cooling, softening in the fSW joint was significantly reduced. At a low rotation rate of 200 rpm with additional water cooling, almost no obvious softening was observed in the fSW joint, and therefore a fSW5083Al-H19 joint with nearly equal strength to the base material(BM) was obtained. furthermore, the grains in the nugget zone were considerably refined with reducing the heat input and ultrafine equiaxed grains of about 800 nm were obtained in the lowest heat input condition. This work provides an effective method to achieve high property fSW joints of precipitate-hardened and work-hardened Al alloys.

关键词： friction stir welding Aluminum alloy Water cooling Microstructure Mechanical property

基于MATLAB的二重积分计算在教学中的应用

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人文之友 2019年第19期 57-57页

作者：李娜汪敏王芃凡方泽兵高琼张庆平安庆师范大学物理与电气工程学院安徽安庆246133

本文以二重积分为例,探讨用Matlab计算重积分精确解的方法,并用高等数学课本的例题加以检验,结论与教材一致.此方法可广泛用于涉及二重积分的教学或计算场合,如高等数学、大学物理课程等,具有高效、准确的特点.

关键词： Matlab 二重积分教学案例

Momentum and heat transfer of a special case of the unsteady stagnation-point flow

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Applied Mathematics and Mechanics(English Edition) 2020年第1期41卷 51-82页

作者： T.G.fANG f.J.wang Mechanical and Aerospace Engineering Department North Carolina State University

This paper investigates the unsteady stagnation-point flow and heat transfer over a moving plate with mass transfer,which is also an exact solution to the unsteady Navier-Stokes(NS)*** boundary layer energy equation is solved with the closed form solutions for prescribed wall temperature and prescribed wall heat flux *** wall temperature and heat flux have power dependence on both time and spatial *** solution domain,the velocity distribution,the flow field,and the temperature distribution in the fluids are studied for different controlling *** parameters include the Prandtl number,the mass transfer parameter at the wall,the wall moving parameter,the time power index,and the spatial power *** is found that two solution branches exist for certain combinations of the controlling parameters for the flow and heat transfer *** heat transfer solutions are given by the confluent hypergeometric function of the first kind,which can be simplified into the incomplete gamma functions for special *** wall heat flux and temperature profiles show very complicated variation *** wall heat flux can have multiple poles under certain given controlling parameters,and the temperature can have significant oscillations with overshoot and negative values in the boundary *** relationship between the number of poles in the wall heat flux and the number of zero-crossing points is *** difference in the results of the prescribed wall temperature case and the prescribed wall heat flux case is *** given in this paper provide a rare closed form analytical solution to the entire unsteady NS equations,which can be used as a benchmark problem for numerical code validation.

关键词： unsteady stagnation point flow Navier-Stokes(NS)equations analytical solution heat transfer

Gut virome:New key players in the pathogenesis of inflammatory bowel disease

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World Journal of Methodology 2025年第2期15卷 27-43页

作者： Helal f Hetta Rehab Ahmed Yasmin N Ramadan Hayam fathy Mohammed Khorshid Mohamed M Mabrouk Mai Hashem Department of Medical Microbiology and Immunology Faculty of MedicineAssiut UniversityAssiut 71515Egypt Division of Microbiology Immunology and BiotechnologyFaculty of pharmacyUniversity of TabukTabuk 71491Saudi Arabia Division of Microbiology Immunology and BiotechnologyDepartment of Natural Products and Alternative MedicineFaculty of PharmacyUniversity of TabukTabuk 71491Saudi Arabia Department of Internal Medicine Division HepatogastroenterologyAssiut UniversityAssiut 71515Egypt Department of Clinical Research Egyptian Developers of Gastroenterology and Endoscopy FoundationCairo 11936Egypt Department of Internal Medicine Faculty of Medicine.Tanta UniversityTanta 31527Egypt Department of Tropical Medicine Gastroenterology and HepatologyAssiut University HospitalAssiut 71515Egypt

Inflammatory bowel disease(IBD)is a chronic inflammatory illness of the *** the mechanism underlying the pathogenesis of IBD is not fully under-stood,it is believed that a complex combination of host immunological response,environmental exposure,particularly the gut microbiota,and genetic suscept-ibility represents the major *** gut virome is a group of viruses found in great frequency in the gastrointestinal tract of *** gut virome varies greatly among individuals and is influenced by factors including lifestyle,diet,health and disease conditions,geography,and *** majority of research has focused on the significance of gut bacteria in the progression of IBD,although viral populations represent an important component of the *** conducted this review to highlight the viral communities in the gut and their expected roles in the etiopathogenesis of IBD regarding published research to date.

关键词： Inflammatory bowel disease Pathogenesis Gut virome Bacteriophage Eukaryotic viruses

C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2231-2244页

作者： Xiangzi wang Xiaofei Niu Yingkai wang Yang Liu Cheng Yang Xuyi Chen Zhongquan Qi School of Medicine Guangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Graduate School of Tianjin University of Traditional Chinese Medicine TianjinChina Characteristic Medical Center of People’s Armed Police forces TianjinChina fujian Maternity and Child Health Hospital FuzhouFujian ProvinceChina

Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory *** expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after *** studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for *** review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord ***,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted ***,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.

关键词： apoptosis C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway C-C motif chemokine receptor 2 antagonists chemokine ligand 2 chemokine receptor 2 inflammation macrophage microglia spinal cord injury therapeutic method

Gamma oscillations and their role in orchestrating balance and communication following stroke

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Neural Regeneration Research 2025年第2期20卷 477-478页

作者： Montana Samantzis Cong wang Matilde Balbi Queensland Brain Institute The University of QueenslandBrisbaneQLDAustralia Engineering Research Centre of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina

Induced brain oscillations in the gamma range have recently garnered attention due to their reported neuroprotective effects in the treatment of Alzheimer’s *** method differs from pharmacological approaches by tapping into the neuronal population dynamics that underlie the homeostatic processes in the brain that are crucial for the recovery of ***,induced gamma-range oscillations have been used to improve cerebral blood flow,motor function,and synaptic plasticity in a mouse model of focal stroke,highlighting the broad potential of recruiting intrinsic recovery processes for the treatment of neurological *** open questions,such as the frequency specificity of the benefits,will shed light on the intrinsic processes involved and allow clinicians to optimize recovery after stroke.

关键词： protective specificity Alzheimer

fAB MS of Permethylated L-β-Aspartamido-Carbohydrates

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Chemical Research in Chinese Universities 1998年第2期14卷 52-54,56-58页

作者： wang Tsong-hui CHEN T.f. Barofsky D.f. Department of Instrumental Analysis Institute of Forensic ScienceBeijing100038 Department of Agricultural Chemistry Oregon State UniversityCorvallisOregon 97331USA

Native glycopeptides are suitable to fAB mass spectrometric analysis due to their high polarity, low volatility and large molecular size. The deficiency in the fAB spectra of glycopeptides is the limited number of peaks and the low abundances of fragments. In order to obtain the information of carbohydrate sequence the permethylation of carbohydrate, a well known method, is recommended here. The L β aspartamido carbohydrate from chicken egg albumin was chosen as the model compound of glycopeptides. Our experiments showed obvious carbohydrate sequence in the spectra of permethylated aspartamido carbohydrates. The key conditions to perform the method are the methylation reagent and purification process for the permethylated derivatives.

关键词： Glycopeptide Ovalbumin Permethylation fABMS

IN SITU PROCESSING Of Al_(2)O_(3) WHISKERS REINfORCED Ti-Al INTERMETALLIC COMPOSITES

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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 432-440页

作者： f.wang Z.K.fan J.f.Zhu School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China School of Materials Science and Engineering Shaanxi University of Science and TechnologyXianyang 712081China

In situ Al2O3 whiskers reinforced Ti-Al intermetallic composites were fabricated at ~1200℃ by reaction sintering of cold-consolidated fillets consisting mainly of Ti, Al, and different additives. The phases and microstructures of the sintered composites were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (EDS). The process of synthesis was investigated using differential thermal analysis (DTA). The effects of processing parameters and additives on the microstructures of the composites and the development of whisker were examined. It is found that the morphology of the whisker is strongly influenced by the additives, the exothermal reaction process, and the processing parameters.

关键词： in situ Al2O3 whisker Ti-Al intermetallic composite additive reaction process