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Acta Mechanica Solida Sinica 2008年第1期21卷 34-43页

作者： yong-Dong Li Wei Tan kang yong Lee Department of Mechanical Engineering Academy of Armored Force Engineering No.21 Du Jia Kan Chang Xin Dian Beijing 100072 China School of Mechanical Engineering Yonsei University Seoul 120-749 South Korea

The problem considered is a mode Ⅲ crack lying parallel to the interface of an exponential-type functional graded material （FGM） strip bonded to a linear-type FGM substrate with infinite thickness. By applying the Fourier integral transform, the problem was reduced as a Cauchy singular integral equation with an unknown dislocation density function. The collocation method based on Chebyshev polynomials proposed by Erdogan and Gupta was used to solve the singular integral equation numerically. With the numerical solution, the effects of the geometrical and physical parameters on the stress intensity factor （SIF） were analyzed and the following conclusions were drawn：（a） The region affected by the interface or free surface varies with the material rigidity, and higher material rigidity will lead to bigger affected region. （b） The SIF of the crack in the affected region and parallel to the micro-discontinuous interface is lower than those of the weak discontinuous cases. Reducing the weak-discontinuity of the interface will be beneficial to decrease the SIF of the interface-parallel crack in the region affected by the interface. （c） The effect of the free surface on SIF is more remarkable than that of the interface, and the latter is still more notable than that of the material rigidity. When the effects of the interface and free surface are fixed, increase of the material rigidity will enhance the value of SIF.

关键词： bi-FGM composite mode Ⅲ crack stress intensity factor weak/mico discontinuity,the Cauchy singular integral equation

Lian-Cang Xu： the founder of managemen＇ psychology in China

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Protein & Cell 2018年第3期9卷 241-243页

作者： Jing Li yong-kang Lu School of Psychology Nanjing Normal University Nanjing 210097 China

Dr. Lian-Cang Xu （徐联仓, 1927-2015）, born in Haining County, Zhejiang Province, China, is a well-known Chinese psychologist （Fig. 1）, the founder of management psychology in China, and also the pioneer of industr...

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Interstitial Solution Carbon Concentration and Defects of Ti+Nb ULC-BH Steel by Internal Friction and Positron Annihilation Methods

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Journal of Iron and Steel Research International 2014年第1期21卷 91-97页

作者： Ji-ping CHEN yong-lin kang School of Metallurgical Engineering Key Laboratory of Metals and Processing of Anhui Province Anhui University of Technology School of Materials Science and Engineering State Key Laboratory for Advanced Metals and MaterialsUniversity of Science and Technology Beijing

The interstitial solution carbon concentration and defects in continuously annealed Ti＋Nb bearing ULC- BH （ultra-low carbon bake hardening） steel samples are investigated by multi-functional internal friction apparatus, positron annihilation lifetime spectroscopy （PALS） and coincidence Doppler broadening spectroscopy （CDBS）. The relationship of internal friction peaks, interstitial solution carbon concentrations and movable dislocations in the sam- ples under different conditions is analyzed. A correlation of lifetime component v~ values with interstitial solution car- bon concentrations in the samples for different continuous annealing processes is established, while a correlation of li- fetime component r2 values with multi-vacancies, vacancy clusters, microvoids and other types of defects for various continuous annealing processes is also demonstrated. Furthermore, the average lifetime results illustrate the overall defect densities for various continuous annealing processes. The CDBS analysis reflects the chemical surroundings of the defects at the annihilation sites and reveals that the peak heights of the ratio curves relate to the total number of defects such as interstitial carbon atoms, dislocations, vacancies and other types of defects. The results show that in- ternal friction, PALS and CDBS are effective techniques to identify and characterize the interstitial solution carbon concentration, multi-vacancies, vacancy clusters, microvoids and other types of microscopic defects in annealed Ti＋ Nb bearing ULC-BH steel.

关键词： ULC-BH steels internal frictions positron annihilation lifetimes coincidence Doppler broadening

Influence of coating and dew point on hearth roll pickup

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Journal of Iron and Steel Research International 2019年第6期26卷 647-652页

作者： Xiao-fei Zheng yong-lin kang Jian Zhou School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Shougang Jingtang Iron and Steel United Co. Ltd. Tangshan 063200 Hebei China

Thermal spray coatings have been widely used on hearth rolls in a continuous annealing line to improve steel sheet quality and prolong the roll service life. One of the common defects formed on a working hearth roll is the oxide pickup. The most common cause of the pickup formation is that the active Mn oxide reacts with coating. The potentials of two different coatings, CoCrAlYTa-Al2O3 (No. 1) and CoCrYNi-Y2O3 (No. 2), to duplicate pickups by reacting with Fe and Mn oxides were studied. There are three stages during pickup producing and growing. No. 2 coating effectively reduced the corrosion of Mn oxide. The characterization and modification of the surface oxide formed can be changed with different dew points. The results indicate that the dew point from — 53 to — 10 ℃ can change the depth of Mn oxide, such that an alteration can prevent the first stage and second stage and is good for preventing the pickup growing.

关键词： Pickup Coating Dew point Surface oxide Hearth roll

Effects of mating status on copulation investment by male bushcricket Gampsocleis gratiosa (Tettigoniidae, Orthoptera)

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Science China(Life Sciences) 2006年第4期49卷 349-353页

作者： GAO yong kang Le Stake Key Laboratory of Integrated Management of Pest Insects & Rodents Institute of Zoology Chinese Academy of Sciences Beijing 100080 China Stake Key Laboratory of Integrated Management of Pest Insects & Rodents Institute of Zoology Chinese Academy of Sciences Beijing 100080 China

Male’s copulation investment, including spermatophore; sperm investment were very high in the Chinese bushcricket Gampsocleis gratiosa. The effects of mating status of both males; females on male’s copulation investment were examined in this study. The fresh weight of spermatophylax increased positively with the weight of males’ body. This indicated that the nutritional investment during copulation depended on male’s quality. Spermatophore investment showed insignificant differences in every copulation protocols. This finding supported the paternal investment hypothesis, that is, males contributed to their offspring with little attention to their partners. Sperm releasing per ejaculation varied significantly among the trials. Males decreased 54.19% sperm in second mating than in its first mating, demonsrated that males regarded the first mating highly,; were more prudent in subsequent mating. These males’ strategies may contribute to the viability of the offspring.

关键词： virgin effect, ejaculate size, copulation investment, Gampsocleis gratiosa.

Seismic performance evaluation of steel frame-steel plate shear walls system based on the capacity spectrum method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 322-329页

作者： Jian-hua SHAO Qiang GU yong-kang SHEN College of Civil Engineering Hohai University Nanjing 210098 China Department of Civil Engineering Suzhou University of Science and Technology Suzhou 215011 China

This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the base shear force-roof displacement curve of structure is converted to the capacity spectrum of an equivalent single-degree-of-freedom （SDOF） system. The capacity spectrum method （CSM） is programmed by means of MATLABT.0 computer language. A dual lateral force resisting system of 10-story steel frame-steel plate shear walls （SPSW） is designed according to the corresponding China design codes. The base shear force-roof displacement curve of structure subjected to the monotonic increasing lateral inverse triangular load is obtained by applying the equivalent strip model to stimulate SPSW and by using the finite element analysis software SAP2000 to make Pushover analysis. The seismic performance of this dual system subjected to three different conditions, i.e. the 8-intensity frequently occurred earthquake, fortification earthquake and seldom occurred earthquake, is evaluated by CSM program. The excessive safety of steel frame-SPSW system designed according to the present China design codes is pointed out and a new design method is suggested.

关键词： Steel frame-steel plate shear walls (SPSW) system Capacity spectrum method (CSM) Seismic demand spectrum Base shear force-roof displacement Seismic performance evaluation

Faecal microbiota transplantation enhances efficacy of immune checkpoint inhibitors therapy against cancer

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World Journal of Gastroenterology 2021年第32期27卷 5362-5375页

作者： yong-Bo kang Yue Cai Department of Microbiology and Immunology School of Basic Medical SciencesShanxi Medical UniversityJinzhong 030600Shanxi ProvinceChina

Even though immune checkpoint inhibitors(ICIs)are effective on multiple cancer types,there are still many non-responding patients.A possible factor put forward that may influence the efficacy of ICIs is the gut ***,faecal microbiota transplantation may enhance efficacy of ***,the data available in this field are insufficient,and relevant scientific work has just *** a result,the current work reviewed the latest research on the association of gut microbiota with ICI treatments based on anti-programmed cell death protein 1 antibody and anti-cytotoxic T-lymphocyte-associated protein 4 antibody and explored the therapeutic potential of faecal microbiota transplantation in combination with ICI therapy in the future.

关键词： Gut microbiome Immunotherapy Programmed cell death protein 1/programmed cell death protein ligand 1 Cytotoxic T-lymphocyte-associated protein 4 Immune checkpoint inhibitors resistance Faecal microbiota transplantation

Autophagy and inflammation in ischemic stroke

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Neural Regeneration Research 2020年第8期15卷 1388-1396页

作者： Yun Mo Yin-Yi Sun kang-yong Liu Department of Neurology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Department of Neurology Shanghai Sixth People’s HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Neurology Shanghai university of medicine&health Sciences Affiliated Zhoupu hospitalShanghaiChina

Appropriate autophagy has protective effects on ischemic nerve tissue,while excessive autophagy may cause cell *** inflammatory response plays an important role in the survival of nerve cells and the recovery of neural tissue after *** studies have found an interaction between autophagy and inflammation in the pathogenesis of ischemic *** study outlines recent advances regarding the role of autophagy in the post-stroke inflammatory response as follows.(1)Autophagy inhibits inflammatory responses caused by ischemic stimulation through mTOR,the AMPK pathway,and inhibition of inflammasome activation.(2)Activation of inflammation triggers the formation of autophagosomes,and the upregulation of autophagy levels is marked by a significant increase in the autophagy-forming markers LC3-II and *** stimulates microglia and inhibits ULK1 activity by direct phosphorylation of p38 MAPK,reducing the flux and autophagy level,thereby inducing inflammatory activity.(3)By blocking the activation of autophagy,the activation of inflammasomes can alleviate cerebral ischemic *** can also regulate the phenotypic alternation of microglia through the nuclear factor-κB pathway,which is beneficial to the recovery of neural tissue after *** have shown that some drugs such as resveratrol can exert neuroprotective effects by regulating the autophagy-inflammatory *** studies suggest that the autophagy-inflammatory pathway may provide a new direction for the treatment of ischemic stroke.

关键词： autophagy cerebral ischemia function inflammasome inflammation ischemia/refusion ischemic stroke macroautophagy neuroinflammation oxygen glucose deprivation

Effect of compression direction on the dynamic recrystallization behavior of continuous columnar-grained CuNi10Fe1Mn alloy

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 851-859页

作者： yong-kang Liu Hai-you Huang Jian-xin Xie Key Laboratory for Advanced Materials Processing of the Ministry of Education Institute of Advanced Materials and Technology University of Science and Technology Beijing Beijing Laboratory of Metallic Materials and Processing for Modern Transportation

The dynamic recrystallization（DRX） behavior of continuous columnar-grained（CCG） Cu Ni10Fe1 Mn alloy was investigated by hot compression along the solidification direction（SD） and perpendicular to the solidification direction（PD）. Specimens were compressed to a true strain of 0.8 at temperatures ranging from 25°C to 900°C and strain rates ranging from 0.01 to 10 s-1. The results indicate that DRX nucleation at grain boundaries（GBs） and DRX nucleation at slip bands（SBs） are the two main nucleation modes. For SD specimens, C-shaped bending and zig-zagging of the GBs occurred during hot compression, which made DRX nucleation at the GBs easier than that at the SBs. When ln Z ≤ 37.4（Z is the Zener–Hollomon parameter）, DRX can occur in SD specimens with a critical temperature for the DRX onset of;50°C and a thermal activated energy（Q） of 313.5 k J·mol-1. In contrast, in PD specimens, the GBs remained straight, and DRX nucleation occurred preferentially at the SBs. For PD specimens, the critical temperature is about 700°C, Q is 351.7 k J·mol-1, and the occurrence condition of DRX is ln Z ≤ 40.1. The zig-zagging of GB morphology can significantly reduce the nucleation energy at the GBs; as a result, DRX nucleation occurs more easily in SD specimens than in PD specimens.

关键词： copper–nickel alloys columnar grains compressive d

Characteristics of Oscillation in Cavity of Helmholtz Nozzle Generating Self‑excited Pulsed Waterjet

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 264-274页

作者： Miao Yuan Deng Li yong kang Hanqing Shi Haizeng Pan Hubei Key Laboratory of Waterjet Theory and New Technology Wuhan UniversityWuhan 430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China

Cavity flow oscillations in the axisymmetric cavity are critical to the operating efficiency of self-excited pulsed waterjets,which are widely employed in many practical *** this study,the behaviors of a turbulent flow in axisymmetric cavities causing cavity flow oscillations are investigated based on wall pressure *** are performed using four Helmholtz nozzles with varying length-to-radius ratios at flow velocities of 20–80 m/*** orders of hydrodynamic modes in axisymmetric cavity are obtained through the spectral analysis of wall *** on the experimental results,the empirical coefficient of Rossiter’s formula is modified,and the values of the parameter phase lag and the ratio of convection velocity to free stream velocity are obtained as 0.061 and 0.511,*** addition,the spectral peak with a relatively constant frequency shows that the flow-acoustic resonance is excited significantly.A modified model is introduced based on the fluidic networks to predict the lockon *** results obtained can provide a basis for the structural optimization of the nozzle to improve the performance of self-excited pulsed waterjets.

关键词： Self-excited cavitation waterjet Flow-excited oscillations Frequency characteristics Vibration analysis