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Parametric study on single shot peening by dimensional analysis method incorporated with finite element method

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Acta Mechanica Sinica 2012年第3期28卷 825-837页

作者： Xian-Qian Wu Xi Wang Yan-Peng wei hong-wei song Chen-Guang Huang Key Laboratory for Hydrodynamics and Ocean Engineering Institute of MechanicsChinese Academy of Sciences100190 BeijingChina

Shot peening is a widely used surface treatment method by generating compressive residual stress near the surface of metallic materials to increase fatigue life and re- sistance to corrosion fatigue, cracking, etc. Compressive re- sidual stress and dent profile are important factors to eval- uate the effectiveness of shot peening process. In this pa- per, the influence of dimensionless parameters on maximum compressive residual stress and maximum depth of the dent were investigated. Firstly, dimensionless relations of pro- cessing parameters that affect the maximum compressive residual stress and the maximum depth of the dent were de- duced by dimensional analysis method. Secondly, the in- fluence of each dimensionless parameter on dimensionless variables was investigated by the finite element method. Fur- thermore, related empirical formulas were given for each di- mensionless parameter based on the simulation results. Fi- nally, comparison was made and good agreement was found between the simulation results and the empirical formula, which shows that a useful approach is provided in this pa- per for analyzing the influence of each individual parameter.

关键词： Keywords Shot peening - Maximum compressive residualstress Maximum depth of the dent Dimensional analysismethod ~ Finite element method

Research on Effect of Four Natural Ultraviolet Light Absorbers on Photostabilization of Azadirachtin-A

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Agricultural Sciences in China 2006年第11期5卷 855-858页

作者： TAN wei-hong song Zhan-qian Institute of Chemical Industry of Forest Products/Key Laboratory on Forest Chemical Engineering Chinese Academy of Forestry Nanjing 210042 P.R.China

This study examined the photostabilization of Azadirachtin-A （Aza-A） when exposed to ultraviolet light in the presence of some natural absorbers. Aza-A extract solutions with and without natural UV light absorbers in methanol were applied onto the surface of glass slides. At particular intervals, the remaining concentration of Aza-A was analyzed by HPLC. Using first-order kinetic equation, the dissipation half-life values （DT^0） for the degradation of Aza-A under ultraviolet radiation were obtained. It indicated that the addition of ferulic acid, gallic acid, and rutin provided moderate degree of photostabilization of Aza-A and that addition of aloin provided the best photostabilization of Aza-A, among these UV absorbers studied. Photostabilization of Aza-A by different UV light absorbers appears to be due to the competitive energy absorption of UV photons by the absorbers molecules. The dissipation half-life values of Aza-A after irradiation under ultraviolet light suggested that the addition of aloin （in 1 ： 1 mol ratio） can provide better photostabilization of azadirachtin molecule.

关键词： ultraviolet light photostabilization Aza-A bioinsecticide

What is the destiny of a threatened fish, Ptychobarbus chungtienensis, now that non-native weatherfishes have been introduced into Bita Lake, Shangri-La？

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Zoological Research 2016年第5期37卷 275-280页

作者： Wan-Sheng JIANG Tao QIN wei-Ying WANG Ya-Peng ZHAO Shu-Sen SHU wei-hong song Xiao-Yong CHEN Jun-Xing YANG State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China Southeast Asia Biodiversity Research Institute Chinese Academy of Sciences Yezin Nay Pyi Taw 05282 Myanmar POWERCHINA Kunming Engineering Corporation Limited Kunming Yunnan 650051 China Management Division of Yunnan Bitahai Nature Reserve Shangri-La Yunnan 674400 China

Biological invasion is a pervasive negative force of global change, especially in its effects on sensitive freshwater ecosystems. Even protected areas are usually not immune. Ptychobarbus chungtienensis is a threatened freshwater fish now almost confined to Bita Lake, in the Shangri-La region of Yunnan province, China. Its existence is threatened by the introduction of non-native weatherfishes （Misgumus anguillicaudatus and Paramisgurnus dabryanus） by an unusual method known as ＇prayer animal release＇ Periodic surveys revealed the ratio of invasive weatherfishes to P. chungtienensis has been increasing since the former species was first recorded from the lake in August, 2009. Ptychobarbus chungtienensis shows low genetic diversity in the relict Lake Bita population. Weatherfishes, however, have highly successful survival strategies. The degree of dietary overlap between the species is alarming and perhaps critical if food is found to be a limiting factor.

关键词： Biological invasion Threatened fish Prayer animal release Genetic diversity Dietary

Recycle Adsorption of Cu2＋ on Amine-functionalized Mesoporous Silica Monolithic

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Chemical Research in Chinese Universities 2013年第4期29卷 793-797页

作者： ZHAO Da-zhou JING Shu-bo XU Jia-ning YANG hong ZHENG wei song Tian-you ZHANG Ping State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

3-Aminopropyltriethoxysilane functionalized worm-like mesoporous silica monolithic（WMSM-NH2） was prepared and used as a new regenerable adsorbent for the removal of Cu2＋ ions. The analysis results show that the WMSM-NH2 monolithic had a high efficiency value of 99.3% for Cu2＋ remediation when the Cu2＋ solution was at an initial concentration of 10.32 mg/L. The regeneration study of the WMSM-NH2 monolithic presented that the adsorp- tion efficiency of 89.0% was remained and a mass of 92.0% was left after seven adsorption-desorption cycles were executed. The monolithic material with high resistance to the acid and good mechanical stability can facilitate the operations of adsorption and regeneration of the adsorbent.

关键词： Amine-functionalized mesoporous silica monolithic(WMSM-NH2) Cu2+ removal Multiple cycle Adsorp- tion Easy operation

Understanding Rotational Mode Specificity in the O（3P）+CHD3→OH+CD3 Reaction by Simple Reactant Alignment Pictures

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Chinese Journal of Chemical Physics 2019年第1期32卷 46-52,I0001页

作者： Rui Liu hong-wei song Ming-hui Yang Key Laboratory of Magnetic Resonance in Biological Systems National Center for Magnetic Resonance in Wuhan State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China

The mode specificity plays an important role in understanding the fundamental reaction dynamics. This work reports a theoretical study of the rotational mode specificity of the reactant CHD3(JK) in the prototypical hydrocarbon oxidation reaction O(3P)+CHD3→OH+CD3. The time-dependent quantum wave packet method combined with a seven-dimensional reduced model is employed to calculate the reaction probability on an accurate potential energy surface. The obtained reaction probability depends on the values of both K and Ktot with PKtot=K=0>PKtot=K=J>PKtot=J,K=0=PKtot=0,K=J. This observation can be well rationalized by the reactant alignment pictures. Rotational excitations of CHD3 up to the angular momentum quantum number J=4 have a very weak enhancement effect on the reaction except for the state (J=4, K=0). In addition, the rotationally excited states of CHD3 with K=0 promote the reaction more than those with K=J. The quantum dynamics calculations indicate that the K=0 enhancements are mainly caused by the contributions from the components with K=Ktot=0. The components correspond to the tumbling rotation of CHD3, which enlarges the range of the reactive initial attack angles.

关键词： Polyatomic reaction Rotational excitation Time-dependent wave packet

Decreases of voltage-dependent K~+ currents densities in ventricular myocytes of guinea pigs by chronic oxidant stress

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Acta Pharmacologica Sinica 2004年第6期25卷 49-53页

作者： De-li DONG, Yan LIU, Yu-hong ZHOU,wei-hua song, He WANG, Bao-feng YANG2 Department ofpharmacology, Harbin Medical University, Harbin 150086, China Department of pharmacology Harbin Medical University

AIM: To determine the changes of delayed rectifier K+ currents (Ik) and inward rectifier K+ currents (Ik1) in the ventricular myocytes of guinea pigs during the gradual apoptotic process by the chronic oxidant stress treatment. METHODS: H2O250 μmol/L (24 h) was used for inducing apoptosis in the cardiomyocytes culture of neonatal rats and to treat the isolated ventricular myocytes of adult guinea pigs in vitro for 24 h. Apoptosis was evaluated by TUNEL methods and voltage-dependent K+ currents were recorded by patch-clamp techniques. RESULTS: H2O2 50 μmol/L (24 h)induced cell apoptosis in the cardiomyocytes culture of neonatal rats. This concentration was used to treat the isolated ventricular myocytes of adult guinea pigs in vitro for 24 h and the voltage-dependent K+ currents densities (Ik, Ik1) were down-regulated. The densities of the delayed rectifier K+ currents (Ik) in 50 μmol/L H2O2 group were 2.52±0.57 pA/pF vs 5.73±1.84 pA/pF in the control group at +50 mV (n=8, P<0.01). The densities of the inward rectifier K+ currents (Ik1) in 50 μmol/L H2O2 group were -13.9± 2.70 pA/pF, 2.52±0.57 pA/pF vs -59.7±11.9 pA/pF, 5.73±1.84 pA/pF in the control group at -120 mV (n=8, P< 0.01) and -40 mV (n=8, P<0.05), respectively. The extent of inward rectifier property of Ik1 was weakened by 50 μmol/L H2O2treatment. CONCLUSION: The densities of Ik, Ik1 in the cardiomyocytes of guinea pigs were down- regulated and the inward rectifier property of Ik1 was weakened during the gradual apoptotic process after 50 μmol/L H2O2 treatment for 24 h.

关键词： hydrogen peroxide potassium apoptosis cardiac myocytes

A New Many-Body Expansion Scheme for Atomic Clusters:Application to Nitrogen Clusters

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Chinese Journal of Chemical Physics 2021年第6期34卷 717-727,I0002页

作者： wei Yan Yong-fa Zhu wei-yu Xie hong-wei song Chao-yang Zhang Ming-hui Yang State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430071China

Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal *** this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent *** this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding *** IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body *** results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE *** weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.

关键词： Many-body expansion Covalent bond Nitrogen cluster

(K0.45Na0.55)NbO3无铅压电晶体的生长形态与介电性能研究

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物理学报 2011年第10期60卷 668-673页

作者：陈超江向平卫巍李小红魏红斌宋福生江西省先进陶瓷材料重点实验室景德镇陶瓷学院材料学院景德镇333001

采用高温熔融法制备出了尺寸达5mm×3mm×1mm的(K0.45Na0.55)NbO3(KNN)无铅铁电晶体.XRD测试结果表明KNN晶体结构为纯的钙钛矿正交相结构,晶体的显露面为〈001〉结晶面.SEM显微结构分析表明晶体沿[001]方向呈现层状生长台阶,采用负离子... 详细信息

采用高温熔融法制备出了尺寸达5mm×3mm×1mm的(K0.45Na0.55)NbO3(KNN)无铅铁电晶体.XRD测试结果表明KNN晶体结构为纯的钙钛矿正交相结构,晶体的显露面为〈001〉结晶面.SEM显微结构分析表明晶体沿[001]方向呈现层状生长台阶,采用负离子配位多面体生长基元模型解释了晶体层状台阶的生长机理.研究了晶体样品在室温至500℃温度范围内的介电性能,两个介电异常峰出现在240和405℃,分别对应正交铁电-四方铁电以及四方铁电-立方顺电相相变温度.采用修正后的居里外斯定律研究了KNN晶体的介电弛豫特性,结果表明KNN晶体的介电弛豫特性接近于普通铁电体特征.

关键词： (K0.45Na0.55)NbO3晶体无铅晶体结构介电性能

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