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Design and Analysis of a Novel Compliant Mechanism with RPR Degrees of Freedom 被引量:1
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作者 Shuang Zhang jingfang liu Huafeng Ding 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第5期262-274,共13页
A novel compliant mechanism with RPR degrees of freedom(DOF)is proposed where R and P represent rotation and translation DOFs,respectively.The proposed compliant mechanism is obtained from dimension synthesizing a 2-R... A novel compliant mechanism with RPR degrees of freedom(DOF)is proposed where R and P represent rotation and translation DOFs,respectively.The proposed compliant mechanism is obtained from dimension synthesizing a 2-RPU-UPR rigid parallel mechanism with the method of optimization of motion/force transfer characteristic.R,P and U represent rotation,translation and universal pairs,respectively.Firstly,inverse kinematics and Jacobian matrix are analyzed for the dimensional synthesis.Then,output transmission indexes of branches in the parallel mechanism are given.Dimensional synthesis is completed based on the normalized design parameter.And optimization of flexure joints based on constrained energy is carried out.Afterwards,the novel compliant mechanism is obtained by direct replacing method.Mechanical model of the compliant mechanism including static stiffness and input stiffness is built based on the pseudo-rigid body modeling method and virtual work principle.Finally,FEA simulation by Ansys Workbench is carried out to verify DOF,effectiveness of the dimension synthesis,and compliant model.Optimization of motion/force transfer characteristic is first applied for the design of compliant mechanisms to suppress drift of rotation axis in the paper. 展开更多
关键词 Compliant mechanism RPR degrees of freedom Motion/force transfer characteristic Mechanical model OPTIMIZATION
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Genome-Wide Analysis of Gene Expression in Stationary Phase and Genetic Characterization of Stationary-Phase-Dependent Halocin Gene Expression in the Haloarchaeon Haloferax mediterranei
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作者 Xiaoqing liu Lei Wang +2 位作者 jingfang liu Lei Cai Hua Xiang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2013年第8期441-444,共4页
The stationary phase of microbial growth is a very complex state regulated by various environmental and physiological factors. An intensive study of stationary phase could promote a comprehensive understanding of the ... The stationary phase of microbial growth is a very complex state regulated by various environmental and physiological factors. An intensive study of stationary phase could promote a comprehensive understanding of the complete life cycle of microorganisms, and may provide important insights into their adaptation to harsh and nutrient-depleted conditions. Although the underlying mechanisms have been weU-studied in bacteria and yeasts (Herman, 2002; Navarro Llorens et al., 2010), less is known about this growth phase in archaea yet. The haloarchaeon Haloferax mediterranei has served as a good model for studying haloarchaeal physiology and metabolism for several decades because of its accelerated growth, remarkable metabolic ability and genomic stability (Han et al., 2012). During stationary phase, H. mediterranei can produce halocin H4 (Cheung et al., 展开更多
关键词 Genome-Wide Analysis of Gene Expression in Stationary Phase and Genetic Characterization of Stationary-Phase-Dependent Halocin Gene Expression in the Haloarchaeon Haloferax mediterranei KEGG BRE gene down
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Specific ion effects on soil aggregate stability and rainfall splash erosion
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作者 jingfang liu Feinan Hu +4 位作者 Chenyang Xu Wei Du Zhenghong Yu Shiwei Zhao Fenli Zheng 《International Soil and Water Conservation Research》 SCIE CSCD 2022年第4期557-564,共8页
Soil interparticle forces can pose important effects on soil aggregate stability and rainfall splash erosion.Meanwhile,these interparticle forces are strongly influenced by specific ion effects.In this study,we applie... Soil interparticle forces can pose important effects on soil aggregate stability and rainfall splash erosion.Meanwhile,these interparticle forces are strongly influenced by specific ion effects.In this study,we applied three monovalent cations(Li^(+),Na^(+),and K^(+))with various concentrations to investigate the influence of specific ion effects on aggregate stability and splash erosion via pipette and rainfall simulation methods.The specific ion effects on soil interparticle forces were quantitatively evaluated by introducing cationic non-classical polarization.The results showed that aggregate stability and splash erosion had strong ion specificity.Aggregate breaking strength and splash erosion rate at the same salt concentration followed the sequence as Li^(+)>Na^(+)>K^(+).With decreasing salt concentration,the difference in aggregate breaking strength or splash erosion rate between different cation systems increased initially(1–10^(-2)mol L^(–1))and later was nearly invariable(10^(–2)–10^(–4)mol L^(–1)).The experimental results were well quantitatively explained by soil interparticle forces considering cationic non-classical polarization.Furthermore,both aggregate breaking strength and splash erosion rate of three cations revealed a strong positive linear relation with net force subjected to cationic non-classical polarization(R^(2)=0.81,R^(2)=0.81).These results demonstrated that different non-classical polarization of cations resulted in different soil interparticle forces,and thus led to differences in aggregate stability and splash erosion.Our study provides valuable information to deeply understand the mechanisms of rainfall splash erosion. 展开更多
关键词 Aggregate breaking Cationic non-classical polarization Soil interparticle forces Splash erosion Surface potential
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Change of Disease Spectrum Characteristics of Psychiatric Inpatients Before and After Lockdown Lifted During the COVID-19 Pandemic—Wuhan City,Hubei Province,China,2021
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作者 jingfang liu Xuan Gong +4 位作者 Xiaofen Li Zhiying Wan Hongqiang Sun Lijun Kang Zhongchun liu 《China CDC weekly》 2022年第18期389-392,I0002-I0004,共7页
Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)pandemic poses a significant threat to mental health globally and may change the proportion of hospitalized patients.What is added b... Summary What is already known about this topic?The coronavirus disease 2019(COVID-19)pandemic poses a significant threat to mental health globally and may change the proportion of hospitalized patients.What is added by this report?This report analyzed and compared the disease characteristics of psychiatric inpatients one year before and after Wuhan lifted lockdown during COVID-19.About 50%of the inpatients were diagnosed with bipolar disorder;females and adolescents had a higher prevalence of mental disorders.What are the implications for public health practice?More attention should be paid to the mental health of children,adolescents,and females. 展开更多
关键词 WUHAN globally COV
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