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ANN Optimization Method for High Strength High Fracture Toughness Steels

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Journal of Materials Science & Technology 1998年第2期14卷 185-187页

作者： geng, ping Tseng, Meikuang Qian, Cunfu Northeastern Univ Coll Sci Shenyang 110006 Peoples R China

The two-target optimization problem for high strength high fracture toughness steels has been investigated. An effective method for two-target optimization of multi-variable nonlinear complicated system was developed... 详细信息

关键词： Steel

How to balance the development of new surgical techniques and protection of patients' health interests

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Hepatobiliary Surgery and Nutrition 2020年第3期9卷 333-335页

作者： Xiao-ping geng Hepatobiliary Surgery Department The First Affiliated Hospital of Anhui Medical University Hefei 230022 China

In 1992,when the usage of laparoscopic cholecystectomy began to rise,Altman(1)published"When Patient's Life Is Price of Learning New Kind of Surgery"in The New York Times.

关键词： Surgery patients Times

Deformation-based longitudinal equivalent stiffness beam model for shield tunnel and its application in seismic deformation method

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Underground Space 2024年第4期17卷 280-299页

作者： pingliang Chen ping geng Junbo Chen Qi Yang Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Intelligent Geotechnics and Tunnelling Chengdu 610031China Technology Center of Sichuan Road&Bridge Group Co. LtdChengdu 610041China

In the longitudinal seismic deformation method for shield tunnels,one of the most commonly used is the longitudinal equivalent stiffness beam model(LES)for simulating the mechanical behavior of the *** this model,axial deformation and bending deformation are independent,so the equivalent stiffness is a constant ***,the actual situation is that axial deformation and bending deformation occur simultaneously,which is not considered in *** present,we are not clear about the effect on the calculation results when axial deformation and bending deformation occur ***,in this paper,we improve the traditional LES by taking the relative deformation as a load and considering the coordinated deformation of axial and bending degrees of *** improved model is called DNLES,and its neutral axis equations are an explicit ***,we propose an iterative algorithm to solve the calculation model of the DNLES-based longitudinal seismic deformation *** a calculation example,we find that the internal forces based on LES are notably underestimated than those of DNLES in the compression bending zone,while are overestimated in the tension bending *** considering the combined effect,the maximum bending moment reached 13.7 times that of the LES model,and the axial pressure and tension were about 1.14 and 0.96 times,*** analysis reveals the coordinated deformation process in the axial and bending directions of the shield tunnel,which leads to a consequent change in equivalent *** explains why,in the longitudinal seismic deformation method,the traditional LES may result in unreasonable calculation results.

关键词： Shield tunnel Longitudinal seismic deformation method Longitudinal equivalent stiffness beam Combined axial and bending deformation

Aging Characteristics, Stress Corrosion Behaviour and Role of Mg Segregation at Grain Boundary in 7175High-strength Al Alloy

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Journal of Materials Science & Technology 1998年第3期14卷 259-264页

作者： Song, Renguo geng, ping Zeng, Meiguang Zhang, Baojin Northeastern Univ Coll Sci Dept Mat Sci Shenyang 110006 Peoples R China

The aging characteristics, stress corrosion behavior and chemical composition of grain boundary in 7175 high-strength Al alloy during long term aging process have been investigated by hardness measurement, constant elongation rate testing (CERT) and energy spectroscopy analysis. The results indicate that double peaks in aged state feature the hardness and strength of 7175 Al alloy. Although the intensity of double peaks is almost equal, the stress corrosion resistance in the second peak-aged state is better than that of the first peak-aged state. The effects of Mg segregation on the binding energy of grain boundary have been calculated by using free electron theory developed in this paper. The results showed that Mg segregation plays a significant role in controlling stress corrosion susceptibility, which is consistent with the experimental results. (Edited author abstract) 32 Refs.

关键词： Aluminum alloys

HSP90 and SIRT3 expression in hepatocellular carcinoma and their effect on invasive capability of human hepatocellular carcinoma cells

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Asian Pacific Journal of Tropical Medicine 2015年第4期8卷 305-308页

作者： Ming Gao Xiao-ping geng He-ping Xiang Department of Emergency Surgery Second Affiliated Hospital of Anhui Medical University Department of General Surgery Second Affiliated Hospital of Anhui Medical University

Objective:To vexplore expression of HSP90,SIRT3 in liver cancer tissue and its effect on liver cancer cell invasion ***:Moderate expression of HSP90 in SMMC-7721,HepG2,LO2 and Hep-3B cell lines were screened,which was validated by *** of HSP90 cell line and lentivirus packaging HSP90-RNAi were established,which was validated by RT-PCR and western *** level of epithelial-mesenchymal transition(EMT)related gene was detected by western *** percentage of cancer stem cells was assayed by flow ***:RT-PCR demonstrated the highest expression of HSP90mRNA in SMMC-7721 cells,the lowest expression of HSP90 mRNA in Hep3B and LO2 and the moderate expression of HSP90 mRNA in ***,HepG2 was selected as a follow-up experiment cell *** with the blank control group,expression of HSP90in HSP overexpression group was increased obviously,and expression of HSP90 in HSP90shRNA group was significantly decreased,which indicated successful establishment of HSP overexpression and shRNA *** apoptotic cell in hsp-siRNA group was higher than the blank control group,while the HSP overexpression group showed opposite *** blot results showed transfection HSP promoted cells EMT transformation,up-regulated the level of E-cadherin,and down-regulated the level of Vimentin;meanwhile,shRNA group showed opposite ***:Carcinoma HepG2 cell transfeeted high expression of HSP can promote the transformation of EMT,improve the expression of Vimentin,reduce the expression of E-cadherin,and inhibit apoptosis of cancer stem cells,which improve the invasive ability of cancer of the liver *** hsp-siRNA group presents opposite *** summary,the expression of HSP is closely related to the occurrence,development and invasion of cancer of the liver tissue.

关键词： HSP90 SIRT3 EMT Cancer stem cell Liver cancer

Performance-based three-level fortification goal and its application in anti-dislocation countermeasures:A case study of Shantou Submarine tunnel

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Underground Space 2023年第5期12卷 251-270页

作者： Tianqiang Wang ping geng Guoguo Liu Changjian Chen Wenqi Gu Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSchool of Civil EngineeringSouthwest Jiaotong UniversityChengdu 610031China

The dislocation momentum is the design basis for anti-dislocation to tunnel when a tunnel crosses an active *** influence of different dislocation levels on tunnel performances is not ***,based on seismic activity parameters at the site of interest and probability of fault dislocation,probability fault displacement hazard analysis(PFDHA)methodology was introduced in this paper to ascertain the fault dislocation level under different exceeding probabilities(63%,10%,and 2%–3%).Then,based on the definition of different ground motion strength and fortification goals of the tunnel,a three-level fortification goal with different performance requirements of the tunnel was *** first attempt to use the proposed indexes including the maximum dislocation of the tunnel and maximum relative deformation of the tunnel was tried to evaluate deformation and failure states with an experimental ***,the feasibility of the three-level fortification goal was further investigated according to the self-defined qualitative description and quantitative indexes in the segmental design and sectional expansion tunnels *** results show that the fault dislocations relying on PFDHA at the site of the Shantou Submarine Tunnel are firstly ascertained as 0.04,1.8,and 2.4 m *** the fault dislocation as model input values into account,the dislocation mechanism of the tunnel under the three levels was *** importantly,judging from the dislocation performance requirements of the three-level fortification goal,the tunnel deformation and failure states are mitigated by adopting the *** sectional expansion design can well meet the requirements without the restriction of a strong earthquake,while the effectiveness of the segmental tunnel can be proved under frequently occurred and fortification *** final research results are expected to provide a new fortification goal for anti-dislocation hazard evalu

关键词： Fault-crossing tunnel PFDHA methodology Three-level fortification goal Failure modes Anti-dislocation countermeasures

Scheme for generating 1 nm X-ray beams carrying orbital angular momentum at the SXFEL

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Nuclear Science and Techniques 2020年第9期31卷 33-44页

作者： He-ping geng Jian-Hui Chen Zhen-Tang Zhao Chinese Academy of Sciences Shanghai Institute of Applied PhysicsShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Chinese Academy of Sciences Shanghai Advanced Research InstituteShanghai 201210China

Optical vortices have the main features of helical wavefronts and spiral phase structures,and carry orbital angular *** special structure of visible light has been produced and studied for various *** notable characteristics of photons were also tested in the extreme-ultraviolet and X-ray *** this article,we simulate the use of a simple afterburner configuration by directly adding helical undulators after the SASE undulators with the Shanghai Soft X-ray FEL to generate high intensity X-ray vortices with wavelengths^1 *** to other methods,this approach is easier to implement,cost-effective,and more efficient.

关键词： X-ray Orbital angular momentum(OAM) Synchrotron light source Free-electron laser(FEL)

Synthesis and Characterization of Ferrocenyl Substituted Styryl Octasilsesquioxane

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Chinese Chemical Letters 2006年第4期17卷 427-430页

作者： Xiao Yan SONG Hai ping geng Qi Fang LI College of material science and engineering Beijing University of Chemical Technology Beijing 100029

4-（2-Ferrocenylethenyl）-phenyl-POSS Fc-CH=CH-C6H6-（C5H9）7Si8O12 （FEPS, Fc： ferrocene）, containing metal and C=C double bond, was firstly synthesized as a mixture of E/Z isomers by the Wittig reaction. The chemi... 详细信息

关键词： Polyhedral silsesquioxane ferrocene Wittig reaction synthesis.

Mechanical response of a tunnel subjected to strike-slip faulting processes,based on a multi-scale modeling method

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1281-1295页

作者： Guoguo LIU ping geng Tianqiang WANG Xiangyu GUO Jiaxiang WANG Ti DING Key Laboratory of Transportation Tunnel Engineering Ministry of EducationChengdu 610031China College of Civil Engineering Huaqiao UniversityXiamen 361021China China Railway Design Corporation Tianjin 300308China

The stick-slip action of strike-slip faults poses a significant threat to the safety and stability of underground *** this study,the north-east area of the Longmenshan fault,Sichuan,provides the geological background;the rheological characteristics of the crustal lithosphere and the nonlinear interactions between plates are described by Burger’s viscoelastic constitutive model and the friction constitutive model,respectively.A large-scale global numerical model for plate squeezing analysis is established,and the seemingly periodic stick-slip action of faults at different crust depths is *** a second model at a smaller scale,a local finite element model(sub-model),the time history of displacement at a ground level location on the Longmenshan fault plane in a stick-slip action is considered as the displacement *** integration of these models,creating a multi-scale modeling method,is used to evaluate the crack propagation and mechanical response of a tunnel subjected to strike-slip *** determinations of the recurrence interval of stick-slip action and the cracking characteristics of the tunnel are in substantial agreement with the previous field investigation and experimental results,validating the multi-scale modeling *** can be concluded that,regardless of stratum stiffness,initial cracks first occur at the inverted arch of the tunnel in the footwall,on the squeezed side under strike-slip *** smaller the stratum stiffness is,the smaller the included angle between the crack expansion and longitudinal direction of the tunnel,and the more extensive the crack expansion *** the tunnel in a high stiffness stratum,both shear and bending failures occur on the lining under strike-slip faulting,while for that in the low stiffness stratum,only bending failure occurs on the lining.

关键词： stick-slip action plate squeezing analysis multi-scale modeling method lining cracking mechanical response