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Fatigue Life Prediction of Horizontal Press Frame Based on Statistical Probability and Its Redesign

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Journal of Harbin Institute of Technology(New Series) 2014年第2期21卷 43-49页

作者： Wei-Wei Zhang xiao-song wang Bo Yang Shi-Jian Yuan School of Materials Science and Engineering Harbin Institute of Technology AVIC Shenyang Liming Aero-Engine Group Co. Ltd

Horizontal press as an important part of hydro-forming machine is used to output the horizontal force to keep the high internal pressure during tube hydro-forming. However,the horizontal press frame is usually mounted on the press bed and not pre-stressed. Meanwhile it will be subjected to the reaction force caused by liquid pressure. Stresses are concentrated severely on the assemble region due to deformation,and total fatigue life will decrease. In order to predict the total fatigue life of the frame,the simulations are used firstly to determine to stress concentration region,and then strain gauge measurements are carried out under different loads. Next,the methods of statistical probability are conducted to calculate the fatigue life based on long-term load history. Finally a structure with the considerable longer fatigue life is redesigned.

关键词： horizontal press statistical probability fatigue life prediction structure redesign

Stress Analysis of Ellipsoidal Shell with Inner Guide Structure

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Journal of Harbin Institute of Technology(New Series) 2014年第5期21卷 96-100页

作者： Wei-Wei Zhang xiao-song wang Meng Chen Shi-Jian Yuan National Key Laboratory of Precision Hot Processing of Metals Harbin Institute of Technology

In order to overcome stress concentration and increase fatigue life of ellipsoidal shells with inner guide structure,the stress analysis for strength check is very important. Owing to the main sectional profile with ellipsoidal shape,the stress distribution for perfect ellipsoidal shell is firstly conducted based on the theoretical calculation and strain gauges measurement. The experiment results show that the stresses increase gradually from pole region to equatorial plane,but still within elastic range. Secondly,strain gauge measurement for ellipsoidal shells with inner guide structure is conducted. The results show that stresses are concentrated at the vicinity of bottom plate and beyond elastic range,so the structural redesign is needed. Finally based on the analysis mentioned above,a redesigned structure with local thickening is proposed. Experimental research shows that the stress varies more even after structural redesign and within allowable range. Numerical simulation shows that both the deformation and fatigue life after redesign are acceptable.

关键词： Iellipsoidal shell strain gauge measurement redesign fatigue life

Tolman length of simple droplet: Theoretical study and molecular dynamics simulation

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Chinese Physics B 2021年第1期30卷 443-448页

作者： Shu-Wen Cui Jiu-An Wei Qiang Li Wei-Wei Liu Ping Qian xiao song wang Department of Physics and Information Engineering Cangzhou Normal UniversityCangzhou 061001China State Key Laboratory of Nonlinear Mechanics(LNM)and Key Laboratory of Microgravity Institute of MechanicsChinese Academy of SciencesBeijing 100190China Silfex a Division of Lam Research950 South Franklin StreetEatonOhio 45320USA Department of Physics University of Science and Technology BeijingBeijing 100083China Institute of Mechanics and Power Engineering Henan Polytechnic UniversityJiaozuo 454003China

In 1949, Tolman found the relation between the surface tension and Tolman length, which determines the dimensional effect of the surface tension. Tolman length is the difference between the equimolar surface and the surface of tension. In recent years, the magnitude, expression, and sign of the Tolman length remain an open question. An incompressible and homogeneous liquid droplet model is proposed and the approximate expression and sign for Tolman length are derived in this paper. We obtain the relation between Tolman length and the radius of the surface of tension(R_(s)) and found that they increase with the Rs decreasing. The Tolman length of plane surface tends to zero. Taking argon for example, molecular dynamics simulation is carried out by using the Lennard–Jones(LJ) potential between atoms at a temperature of 90 K. Five simulated systems are used, with numbers of argon atoms being 10140, 10935, 11760, 13500, and 15360, respectively. By methods of theoretical study and molecular dynamics simulation, we find that the calculated value of Tolman length is more than zero, and it decreases as the size is increased among the whole size range. The value of surface tension increases with the radius of the surface of tension increasing, which is consistent with Tolman’s theory. These conclusions are significant for studying the size dependence of the surface tension.

关键词： Tolman length surface tension radius of surface of tension radius of equimolecular surface molecular dynamics simulation

Modified Approach for Establishing Filament-induced Permanent Middle Cerebral Artery Occlusion Rats and Mice Models

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Chinese Medical Sciences Journal 2011年第4期26卷 257-258页

作者： You-xin Ji Ke-tao Lan Chuan-xin Geng xiao Zou song-ping wang Department of Medical Oncology Qingdao Central Hospital Second Affiliated Hospital of Qingdao University Qingdao 266042 China

BRAIN ischemia stroke is a devastating disease,with more than 10％ stroke patients either severely disabled or *** rodent filament middle cerebral artery occlusion (MCAO)model can mimic human brain ischemic stroke well,its wide use was restricted by difficulty in surgery,especially in ligating pterygopalatineartery (PPA).Twenty-seven male Sprague-Dawley rats were randomly divided into A,B,C groups (n=9).All the rats were performed MCAO surgery with sutures of difference *** A used 4-0 blocking suture plus ipsilateral PPA block,group B used 3-0 blocking suture plus ipsilateral common carotid artery (CCA) block,and group C used 3-0 suture plus ipsilateral PPA ***-seven male C57BL/6 wild type mice were also randomly divided into a,b,c *** a used 5-0blocking suture plus ipsilateral PPA block,group b used 6-0blocking suture plus ipsilateral CCA block,group c use 6-0suture plus ipsilateral PPA block.

关键词： SD大鼠小鼠模型动脉闭塞大脑永久性立方纤维

Electrochemical conversion of methane to bridge the gap in the artificial carbon cycle

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Journal of Energy Chemistry 2025年第1期100卷 286-308页

作者： Yuhao Peng Yuefeng song Ihar Razanau Juanxiu xiao Wei xiao Di Hu Guoxiong wang College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power Sources Wuhan University State Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Dalian Institute of Chemical Physics Chinese Academy of Sciences Laboratory of Physical-Chemical Technologies SSPA Scientific and Practical Materials Research Centre of NAS of Belarus State Key Laboratory of Marine Resources Utilization in South China Sea Collaborative Innovation Center of Marine Science and Technology School of Marine Science and Engineering Hainan University Department of Chemical and Environmental Engineering University of Nottingham Ningbo China

Methane, an abundant one-carbon（C1） resource, is extensively used in the industrial production of vital fuels and value-added chemicals. However, current industrial methane conversion technologies are energy-and carbon-intensive, mainly due to the high activation energy required to break the inert C–H bond, low selectivity, and problematic side reactions, including CO2emissions and coke deposition. Electrochemical conversion of methane（ECM） using intermittent renewable energy offers an attractive solution, due to its modular reactor design and operational flexibility across a broad spectrum of temperatures and pressures. This review emphasizes conversion pathways of methane in various reaction systems, highlighting the significance and advantages of ECM in facilitating a sustainable artificial carbon cycle. This work provides a comprehensive overview of conventional methane activation mechanisms and delineates the complete pathways of methane conversion in electrolysis contexts. Based on surface/interface chemistry, this work systematically analyzes proposed reaction pathways and corresponding strategies to enhance ECM efficiency towards various target products, including syngas, hydrocarbons, oxygenates, and advanced carbon materials. The discussion also encompasses opportunities and challenges for the ECM process, including insights into ECM pathways, rational electrocatalyst design, establishment of benchmarking protocols, electrolyte engineering, enhancement of CH4conversion rates, and minimization of CO2emission.

关键词： Methane Electrochemical conversion Reaction mechanism Catalyst design Electrode Electrocatalysis

Quantitative analysis of orange peel during tension of 6063 alloy spun tubes

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Transactions of Nonferrous Metals Society of China 2018年第5期28卷 858-865页

作者： Yang CAI xiao-song wang Shi-jian YUAN School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China National Key Laboratory of Precision Hot Processing of Metals Harbin Institute of Technology Harbin 150001 China

Severe surface roughening during plastic deforming of aluminum alloy parts can produce ＂orange peel＂ defects. To analyze ＂orange peel＂ of 6063 aluminum alloy tube quantificationally, the tensile tests of trapezoidal specimens were carried out. The tubes with different grain sizes were obtained by spinning and subsequent annealing heat treatment. The macroscopical behavior of surface roughening was characterized by surface roughness Ra using a laser scanning confocal microscope. The corresponding microscopic behavior was reflected by microstructures of specimens and in-situ observation using electron back-scattered diffraction（EBSD）. The obtained results show that the surface roughness increased firstly with increasing strain and then decreased slightly. There was a critical strain for aluminum alloy tube, below which ＂orange peel＂ defect would not occur. For the tube with a mean grain size of 80, 105, 130 and 175 μm, the critical strains were 10.17%, 5.74%, 3.15% and 1.62%, respectively. Meanwhile, the surface roughening behavior was produced by serious inhomogeneous deformation between grains as strain increased, and was aggravated as the grain size increased due to the larger local deformation in larger grains.

关键词： 6063 aluminum alloy surface roughening tensile deformation spinning orange peel

Synergistically enhanced ORR and HER performance on Co-N-C coupled in-situ generated PtCo intermetallic

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Journal of Energy Chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min song Lulu An xiao Huang Qian Zhang Chenhao Zhang Tao Shen Shuang wang Deli wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds （IMCs）(o-PtCo@CoNC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a chance for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@CoNC exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-PtCo@CoNC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Electrolytic reduction

Microwave induces apoptosis in A549 human lung carcinoma cell line

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Chinese Medical Journal 2011年第8期124卷 1193-1198页

作者： song xiao-lian wang Chang-hui HU Hai-yang YU Chao BAI Chong Department of Respiratory Changhai Hospital the SecondMilitary Medical University Shanghai 200433 China

Background Microwaves have other biological effects on cancer as well besides killing tumor cells by *** studies showed that microwaves may induce apoptosis in some tumor cells. The apoptotic effect of microwaves may help in clinic to remove residual malignant cells nearby the primary lesion and avoid relapse subsequently. However,there is little evidence on this subject from lung cancer. We studied the effect of microwaves on inducing apoptosis in the human lung carcinoma cell line A549 cells, aiming to identify its effect on *** A549 cells were radiated by various intensities and durations of microwaves. Apoptosis induction in A549 cells was analyzed by morphological observations, tetrazolium blue color method （MTT） assays, flow cytometery,immunohistochemistry, and image *** Morphological changes in A549 cells, including cell shrinking and nuclear pycnosis, were observed after microwave radiation. Microwaves significantly inhibited metabolic activities and induced apoptosis in A549 cells. The results of the MTT assay showed a significant decrease of cell activities in all the radiation groups compared with the normal control （P ＜0.01）. The low point of cell activities often appeared at 6-12 hours after radiation. Apoptosis was also confirmed by flow cytometery. The early stage apoptotic rate reached 6.10%-17.98% and the advanced stage apoptotic rate ＋ necrosis rate reached 8.04%-44.06% at 6 hours after microwave irradiation, in contrast to 2.32% and 4.10% in the respective control groups. Down-regulation of Bcl-2 expression and up-regulation of p53 expression were observed by immunohistochemistry after radiation. In most treated groups, the down-regulation of Bcl-2 expression reached its lowest level at 3-6 hours after radiation （integrated optical density （IOD）-6 hours： 2.13±0.08-5.14±0.13 vs. control： 5.79±0.10, P＜0.01 ） and the up-regulation of P53 expression peaked at about 3 hours （IOD-3 hours： 2.61±0.13-8.07±0.11 vs. c

关键词： microwave lung neoplasms apoptosis A549 cell line

Numerical magnitude processing in abacus-trained children with superior mathematical ability: an EEG study

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2015年第8期16卷 661-671页

作者： Jian HUANG Feng-lei DU Yuan YAO Qun WAN xiao-song wang Fei-yan CHEN Bio-X Laboratory Department of Physics Zhejiang University Department of Psychology and Behavioral Sciences Zhejiang University Heilongjiang Abacus Association

Distance effect has been regarded as the best established marker of basic numerical magnitude processes and is related to individual mathematical abilities. A larger behavioral distance effect is suggested to be concomitant with lower mathematical achievement in children. However, the relationship between distance effect and superior mathematical abilities is unclear. One could get superior mathematical abilities by acquiring the skill of abacus-based mental calculation （AMC）, which can be used to solve calculation problems with exceptional speed and high accuracy. In the current study, we explore the relationship between distance effect and superior mathematical abilities by examining whether and how the AMC training modifies numerical magnitude processing. Thus, mathematical competencies were tested in 18 abacus-trained children （who accepted the AMC training） and 18 non-trained children. Electroencephalography （EEG） waveforms were recorded when these children executed numerical comparison tasks in both Arabic digit and dot array forms. We found that：（a） the abacus-trained group had superior mathematical abilities than their peers; （b） distance effects were found both in behavioral results and on EEG wave- forms; （c） the distance effect size of the average amplitude on the late negative-going component was different between groups in the digit task, with a larger effect size for abacus-trained children; （d） both the behavioral and EEG distance effects were modulated by the notation. These results revealed that the neural substrates of magnitude processing were modified by AMC training, and suggested that the mechanism of the representation of numerical magnitude for children with superior mathematical abilities was different from their peers. In addition, the results provide evidence for a view of non-abstract numerical representation.

关键词： Electroencephalography (EEG) Abacus training Distance effect Numerical magnitude processing Child