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Petroleum Science 2024年第4期21卷 2892-2900页

作者： Bing-jie xu Yi-Fei Shen Hui Qiao Zhi Gao Faculty of Business City University of Macau Rural Development Institute Chinese Academy of Social Sciences School of Marxism Shenzhen Polytechnic University

This study aims to analysis the influence of economic growth(EG) and energy consumption(EC) on sulfur dioxide emissions(SE) in China. Accordingly, this study explores the link between EG, EC, and SE for 30 provinces in China over the span of 2000-2019. This study also analyzes cross-sectional dependence tests, panel unit root tests, Westerlund panel cointegration tests, Dumitrescu-Hurlin(D-H) causality tests. According to the test results, there is an inverted U-shaped association between EG and SE,and the assumption of the Environmental Kuznets Curve(EKC) is verified. The signs of EG and EC in the fixed effect(FE) and random effect(RE) methods are in line with those in the dynamic ordinary least squares(DOLS), fully modified ordinary least squares(FMOLS) and autoregressive distributed lag(ARDL)estimators. Moreover, the results verified that EC can obviously positive impact the SE. To reduce SE in China, government and policymakers can improve air quality by developing cleaner energy sources and improving energy efficiency. This requires the comprehensive use of policies, regulations, economic incentives, and public participation to promote sustainable development.

关键词： SO 2 emissions Economic growth Energy consumption EKC China

Compliance motion control of the hydraulic dual-arm manipulator with adaptive mass estimation of unknown object

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Frontiers of Mechanical Engineering 2024年第1期19卷 35-52页

作者： Bolin SUN min CHENG Ruqi DING Bing xu State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China Key Laboratory of Conveyance and Equipment(ministry of Education) East China Jiaotong UniversityNanchang 330013China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China

Given the limited operating ability of a single robotic arm,dual-arm collaborative operations have become increasingly *** with the electrically driven dual-arm manipulator,due to the unknown heavy load,difficulty in measuring contact forces,and control complexity during the closed-chain object transportation task,the hydraulic dual-arm manipulator(HDM)faces more difficulty in accurately tracking the desired motion trajectory,which may cause object deformation or even *** overcome this problem,a compliance motion control method is proposed in this paper for the *** mass parameter of the unknown object is obtained by using an adaptive method based on velocity *** to the difficulty in obtaining the actual internal force of the object,the pressure signal from the pressure sensor of the hydraulic system is used to estimate the contact force at the end-effector(EE)of two hydraulic manipulators(HMs).Further,the estimated contact force is used to calculate the actual internal force on the ***,a compliance motion controller is designed for HDM closed-chain *** position and internal force errors of the object are reduced by the feedback of the position,velocity,and internal force errors of the object to achieve the effect of the compliance motion of the HDM,i.e.,to reduce the motion error and internal force of the *** required velocity and force at the EE of the two HMs,including the position and internal force errors of the object,are inputted into separate position *** addition,the position controllers of the two individual HMs are designed to enable precise motion control by using the virtual decomposition control ***,comparative experiments are carried out on a hydraulic dual-arm test *** proposed method is validated by the experimental results,which demonstrate improved object position accuracy and reduced internal force.

关键词： hydraulic dual-arm manipulator compliance motion control unknown object adaptive mass estimation nonlinear control

The influence of stress-dependent overpotential on dendrite growth in all-solid-state battery with cracks

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Science China(Technological Sciences) 2024年第8期67卷 2493-2504页

作者： ZHANG ZhenHua ZHANG Yong LIU Chang HOU xu WANG jie Department of Engineering Mechanics School of Aeronautics and AstronauticsZhejiang UniversityHangzhou 310027China Zhejiang Laboratory Hangzhou 311100China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang UniversityHangzhou 310027China School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China Department of Industrial and Systems Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China

Dendrite growth is one of the main challenges in maintaining the service life of all-solid-state lithium-ion *** stress has been reported to significantly affect dendrite *** this study,to explain the effect of mechanical stress on electrochemical reactions in all-solid-state batteries,a modified phase-field model for dendrite growth is proposed by considering the stress-dependent *** growth under different mechanical loadings in an all-solid-state battery is investigated using the proposed *** with previous experimental results,the current result shows that compressive stress inhibits dendrite *** the stress concentration at the tips of processing-induced microcracks,the effects of the number and distribution of microcracks on dendrite growth are *** results show that the stress-concentration field induced at the tips of cracks or voids can change the morphology of dendrites and decrease their growth *** study provides a new perspective for explaining Li dendrite growth under mechanical stress and offers inspiration for prolonging the service life of all-solid-state batteries based on defect and stress regulation,which may be further realized in experiments by filling solid electrolytes with different types of nanofillers.

关键词： Butler–Volmer equation stress-dependent overpotential microcracks all-solid-state battery phase-field simulation

Significantly enhanced performance and conductivity mechanism in Nb/Mn co-doped CaBi_(4)Ti_(4)O_(15)ferroelectrics

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Journal of Materiomics 2024年第3期10卷 652-669页

作者： Jiageng xu Shaoxiong Xie Qian xu jie Xing Qingyuan Wang Jianguo Zhu School of Aeronautics and Astronautics Sichuan UniversityChengdu610000China Institute for Advanced Study Chengdu UniversityChengdu610106China Department of Mechanical Engineering Kyushu UniversityFukuoka819-0395Japan College of Architecture and Environment Sichuan UniversityChengdu610065China College of Material Science and Engineering Sichuan UniversityChengdu610065China

With the rapid development of high-end industries,the demand for high-temperature piezoelectric materials is significantly ***,realizing the ultra-high performance to meet more ap-plications still faces major scientific and engineering challenges of our ***,a new Nb/Mn co-doped CaBi_(4)Ti_(4)O_(15)(CBT)high-temperature piezoelectric material system of CaBi_(4)Ti_(4-x)(Nb_(2/3)Mn_(1/3))_(x)O_(15)was synthesized by the conventional solid-state sintering *** results show that the addition of the dopants tends to break the long-range ferroelectric chain and soften the flexibility of polarization,resulting in more distorted crystal structure and better ferroelectric properties of CBT *** ultra-high piezoelectric constant(d_(33)=26.8 pC/N)is thus attained in CBT-based ceramics with x=0.12,which is about several times larger than that of pure CBT ***,numerous nano-sized layered domain structures that lie on the lateral plane of grains are observed in ceramics,with lower domain wall energy and better dynamic features under electric fields,mainly responsible for the origin of enhanced ***,excess dopants could make the conductivity mechanism of CBT ceramics transform from p-type to n-type,and also result in a shift of conduction relaxation mechanism from defect dipole rotation polarization to electron relaxation *** work not only provides a promising candidate for high-temperature piezoelectric materials,but also opens a window for opti-mizing performance by tailoring domain structures using chemical modification.

关键词： CaBi_(4)Ti_(4)O_(15) Lattice distortion Electrical performance Domain structure Conductivity mechanism

Electromagnetic fields in ultra-peripheral relativistic heavy-ion collisions

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Nuclear Science and Techniques 2024年第2期35卷 103-109页

作者： jie Zhao Jin-Hui Chen xu-Guang Huang Yu-Gang Ma Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China Physics Department and Center for Particle Physics and Field Theory Fudan UniversityShanghai 200438China

Ultra-peripheral heavy-ion collisions(UPCs)offer unique opportunities to study processes under strong electromagnetic *** these collisions,highly charged fast-moving ions carry strong electromagnetic fields that can be effectively treated as photon *** exchange of photons can induce photonuclear and two-photon interactions and excite *** excitation of the ions results in Coulomb dissociation with the emission of photons,neutrons,and other ***,the electromagnetic fields generated by the ions can be sufficiently strong to enforce mutual interactions between the two colliding ***,the two colliding ions experience an electromagnetic force that pushes them in opposite directions,causing a back-to-back correlation in the emitted *** a Monte Carlo simulation,we qualitatively demonstrate that the above electromagnetic effect is large enough to be observed in UPCs,which would provide a clear means to study strong electromagnetic fields and their effects.

关键词： Electromagnetic fields Neutrons Ultra-peripheral relativistic heavy-ion collisions(UPC)

Aerodynamic Performance of Three Flapping Wings with Unequal Spacing in Tandem Formation

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Journal of Bionic Engineering 2024年第4期21卷 1662-1676页

作者： min Chang Ziyi xu Zengshuang Chen Li Li xueguang Meng Unmanned System Research Institute National Key Laboratory of Unmanned Aerial Vehicle TechnologyNorthwestern Polytechnical UniversityXi’an710072People’s Republic of China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049People’s Republic of China Xi’an Aeronautics Computing Technique Research Institute Aviation Industry Corporation of ChinaXi’an710076People’s Republic of China

To better understand the aerodynamic reasons for highly organized movements of flying organisms,the three-flapping wing system in tandem formation was studied numerically in this *** from previous relevant studies on the multiple flapping wings that are equally spaced,this study emphasizes the impact of unequal spacing between individuals on the aerodynamics of each individual wing as well as the whole *** is found that swapping the distance between the first and second wing with the distance between the second wing and the rearmost wing does not affect the overall aerodynamic performance,but significantly changes the distribution of aerodynamic benefits across each *** the whole flapping cycle,three effects are at *** narrow channel effect and the downwash effect can promote and weaken the wing lift,respectively,while the wake capture effect can boost the *** also shows that these effects could be manipulated by changing the spacing between adjacent *** findings provide a novel way for flow control in tandem formation flight and are also inspiring for designing the formation flight of bionic aircraft.

关键词： Three flapping wings Unequal spacing Aerodynamic performance Tandem formation

Prevalence and clinical impact of sarcopenia in liver transplant recipients:A meta-analysis

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World Journal of Gastroenterology 2024年第8期30卷 956-968页

作者： min-jie Jiang Mu-Chen Wu Zhong-Hui Duan Jing Wu Xiao-Tong xu Juan Li Qing-Hua Meng Department of Hepatology Beijing You-An HospitalCapital Medical UniversityBeijing 100069China Department of Emergency Beijing You-An HospitalCapital Medical UniversityBeijing 100069China

BACKGROUND The prevalence of sarcopenia in patients undergoing liver transplantation(LT)remains to be determined partly because of different diagnostic *** has recently been recognized as a new prognostic factor for predicting outcomes in LT *** To estimate the prevalence of sarcopenia and evaluate its clinical effect on LT *** This systematic search was conducted in PubMed,Web of Science,Embase,and Cochrane Library for original English-language articles that investigated the prevalence and influence of sarcopenia in patients undergoing LT from database inception to November 30,*** studies of the definition of sarcopenia that estimate sarcopenia prevalence and evaluate its effect on clinical outcomes and the risk of mortality were *** Twenty-five studies involving 7760 patients undergoing LT were *** pooled prevalence of sarcopenia in patients undergoing LT was 40.7%[95%confidence intervals(95%CI):32.1-49.6].The 1-,3-,and 5-year cumulative probab-ilities of post-LT survival in patients with preoperative sarcopenia were all lower than those without sarcopenia(P<0.05).Sarcopenia was associated with an increased risk of post-LT mortality in patients undergoing LT(adjusted hazard ratio:1.58;95%CI:1.21-2.07).Patients with preoperative sarcopenia had a longer intensive care unit stay,a high risk ratio of sepsis,and serious post-LT complications than those without *** Sarcopenia is prevalent in a substantial proportion of patients undergoing LT and is strongly and independently associated with higher a risk of mortality risk.

关键词： Sarcopenia Liver transplantation Mortality Clinical outcomes

Resolving the geometric structure of trastuzumab by mobility capillary electrophoresis and native mass spectrometry

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Chinese Chemical Letters 2024年第3期35卷 221-225页

作者： Wenjing Zhang jie Hong Lei Yang Zuqiang xu Yu Xiang Wei xu School of Life Science Beijing Institute of TechnologyBeijing 100081China

Available online Immunoglobulins G(IgGs)are Y-shaped globular proteins,however,their high flexibility and heterogeneity pose great challenges to their structure and conformation *** structure of IgG closely correlates to its biofunctions,such as the antibody escape of human immunodeficiency virus(HIV)could attribute to the distance mismatch between the ends of two Fab arms(antigen-binding sites)and envelope glycoprotein spikes on virion ***,we report the first use of mobility capillary electrophoresis(MCE)and native mass spectrometry(nMS)to resolve the internal geometric structure and conformation of an IgG(trastuzumab)in solution *** proteolysis,the ellipsoid dimensions of IgG and its subunits were measured by MCE-nMS *** was then reconstructed,in which the sizes and relative positions of these three subunits in three-dimensional space were *** was found that the two Fab arms have an angle of~102.1°and a distance of~11.0 nm between the two antigen-binding sites under native condition,and the Fc arm was tilted~16.0°towards one of the Fab *** was not on the plane of Fab-Fab,but has an angle of no larger than 103.1°.Under acidic environment(pH 3.0),each subunit of the IgG would unfold into larger dimensions,and the angles between these subunits also *** great potential for tumor imaging and therapy,the structure of F(ab')_(2)fragments was also measured and validated by molecular dynamic *** was found that the electrostatic force among these three subunits and steric hindrance stemming from Fc help maintaining the angle between two Fab arms.

关键词： Native mass spectrometry Mobility capillary electrophoresis Trastuzumab Protein structure Geometric structure

Single-atom catalysis for advanced oxidation and reduction systems in water decontamination

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Rare Metals 2024年第8期43卷 3576-3606页

作者： jie Teng Jin-Hui xu Wen-Xin Sun xue-Feng Liu Xia xu Guo-Shuai Liu School of Urban Construction Changzhou UniversityChangzhou 213164China School of Environmental and Civil Engineering Jiangnan UniversityWuxi 214122China

Water scarcity is an escalating global crisis,posing a severe threat to populations ***,exploring various materials to remove emerging contaminants from freshwater sources has garnered significant *** this regard,single-atom catalysis(SACs) has emerged as a catalyst of scientific progress in water purification and treatment methodologies during recent *** exhibit exceptional catalytic activity,selectivity and stability,due to their near-perfect atom utilization,highly unsaturated coordination environment and uniform reaction ***,a comprehensive and critical review encompassing the successful integration of SACs into water purification processes needs to be *** review aims to accentuate recent trends by presenting the synthesis,structure,and environment and energy application-relevant properties of *** results show that a comprehensive and multi-perspective summary of the advantages of SACs in environmental remediation can have significant benefits,such as fast kinetics,costeffectiveness,*** oxidation and reduction processes of SACs and functional SACs materials in water purification were ***,the last section is devoted to the current research gaps and further perspectives on the application of SACs in water treatment,which are summarized and analyzed.

关键词： Single-atom catalysis Water treatment Oxidation Reduction

Effectiveness of intravitreal ranibizumab for diabetic macular edema in vitrectomized versus non-vitrectomized eyes:a Meta-analysis

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 729-735页

作者： Yi-Heng Wang Qian xu jie Luan Department of Ophthalmology Zhongda HospitalSoutheast UniversityNanjing 210009Jiangsu ProvinceChina School of Medicine Southeast UniversityNanjing 210009Jiangsu ProvinceChina

AIM:To evaluate the effectiveness and safety of intravitreal ranibizumab(IVR)for diabetic macular edema(DME)in vitrectomized versus non-vitrectomized ***:The PubMed,EMBASE,Web of Science,Cochrane,EBSCO were comprehensively searched for studies comparing vitrectomized and non-vitrectomized eyes with *** outcomes of best-corrected visual acuity(BCVA),central macular thickness(CMT),the mean number of intravitreal injection and adverse events were extracted and ***:Six studies involving 641 eyes were *** visual gain significantly improved and CMT significantly reduced in vitrectomized eyes at 6mo and 12mo visits(P<0.05).Although the mean reduction in CMT among non-vitrectomized eyes was significantly greater than in vitrectomized eyes at the 6mo[mean difference(MD)=53.57,95%confidence interval(CI):28.03 to 78.72,P<0.0001]and 12mo(MD=49.65,95%CI:19.58 to 79.72,P=0.01),no significant difference was detected in improvement in BCVA at either 6mo(MD=0.05,95%CI:-0.02 to 0.13,P=0.14)or 12mo(MD=0.03,95%CI:-0.04 to 0.09,P=0.43).Injection number of ranibizumab in non-vitrectomized eyes was significantly less than that in vitrectomized eyes during 6-month period(MD=0.60,95%CI:0.16 to 1.04,P=0.008),while there was no statistically significant difference between the two groups during 12mo of ***:Evidence from current study suggests that IVR was useful for both vitrectomized group and nonvitrectomized group with *** less reduction in macular thickness is found in vitrectomized group,visual improvement between two groups is similar.

关键词： diabetic macular edema ranibizumab vitrectomized eye