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Water Science and Engineering 2019年第3期12卷 196-204页

作者： fu-hai yao Shao-heng Guan He Yang Yuan Chen Huan-feng Qiu Gang Ma Qi-wen Liu School of Water Resources and Hydropower Engineering Wuhan University Wuhan 430072 China School of Civil Engineering and Architecture Wuhan University Wuhan 430070 China Guiyang Engineering Corporation Limited Guiyang 550081 China

Due to the size effects of rockfill materials, the settlement difference between numerical simulation and in situ monitoring of rockfill dams is a topic of general *** constitutive model parameters obtained from laboratory triaxial tests often underestimate the deformation of high rockfill ***, constitutive model parameters obtained by back analysis were used to calculate and predict the long-term deformation of rockfill *** of using artificial neural networks (ANNs), the response surface method (RSM) was employed to replace the finite element simulation used in the optimization *** 27 training samples were required for RSM, improving computational efficiency compared with ANN, which required 300 training *** can be used to describe the relationship between the constitutive model parameters and dam *** inversion results of the Shuibuya concrete face rockfill dam (CFRD) show that the calculated settlements agree with the measured data, indicating the accuracy and efficiency of RSM.

关键词： Shuibuya rockfill dam Parameter back analysis Response surface method Duncan EB model Time-dependent deformation

Exoskeleton active assistance strategy for human muscle activation reduction during linear and circular walking

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Advances in Manufacturing 2024年第3期12卷 484-496页

作者： Wen-Tao Sheng Ke-yao Liang hai-Bin Tang School of Intelligent Manufacturing Nanjing University of Science and TechnologyNanjing210094People’s Republic of China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150001People’s Republic of China

The exoskeleton is employed to assist humans in various domains including military missions,rehabilitation,industrial operation,and activities of daily living(ADLs).Walking is a fundamental ADL,and exoskeletons are capable of reducing the activation and metabolism of lower extremity muscles through active assistance during *** improve the performance of active assistance strategy,this article proposes a framework using an active hip ***,it correlates to an already established Bayesian-based human gait recognition algorithm,with a particular focus on linear and circular walking within industrial and ADL *** theorizing this strategy for exoskeletons,this study further reveals,in part,the activation characteristics of human hip muscles for the instruction and regulation of active assistance duration and onset *** proposed active assistance strategy provides new insights for enhancing the performance of assistive robots and facilitating human robot interaction within the context of ADLs.

关键词： Human-robot interaction Hip exoskeleton Muscle activation Walking assistance

Photoinduced Dehalocyclization to Access Oxindoles Using Formate as a Reductant

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Chinese Journal of Chemistry 2024年第11期42卷 1203-1208页

作者： Wei Ge Jia-Xin Wang Ming-Chen fu yao fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefeiAnhui230026 China Anhui Province Key Laboratory of Value-Added Catalytic Conversion and Reaction Engineering Hefei University of TechnologyHefeiAnhui230009 China

Herein,we report an efficient and practical protocol for the photoinduced dehalocyclization of ortho-halophenylacrylamides with formate by the engagement of a CO_(2) radical anion to access substituted *** method proceeds smoothly under mild conditions and exhibits a wide range of substrate as well as remarkable functional group compatibility.

关键词： Formate CO_(2)Radical ions Oxindole Photocatalysts Cyclization Organohalides

Cobalt-catalyzed reductive alkynylation to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))bonds

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Chinese Chemical Letters 2024年第7期35卷 253-258页

作者： Lei Wan Yizhou Tong Xi Lu yao fu Hefei National Research Center for Physical Sciences at the Microscale iChEMCAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Precision and Intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

Transition-metal-catalyzed cross-electrophile coupling has emerged as a reliable method for constructing carbon–carbon ***,we report a general method,cobalt-catalyzed reductive alkynylation,to construct C(sp)-C(sp^(3))and C(sp)-C(sp^(2))*** presented reaction has a broad substrate scope,enabling the efficient cross-electrophile coupling between alkynyl bromides with alkyl halides and aryl or alkenyl(pseudo)*** presented reaction is conducted under mild conditions,tolerating many functional groups,thus suitable for the modification and synthesis of biologically active molecules.

关键词： Cobalt-catalysis Cross-electrophile coupling Carbon-carbon bond formation Reductive alkynylation Alkyne synthesis

Numerical analysis of hydraulic fracture propagation in deep shale reservoir with different injection strategies

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3558-3574页

作者： Yingjie Xia Mingyu yao Tianjiao Li hai Yang Chun'an Tang School of Civil Engineering Dalian University of TechnologyDalian116024China Deep Underground Engineering Research Center Dalian University of TechnologyDalian116024China CNPC Chuanqing Drilling Engineering Company Limited Chengdu610051China

Deep shale reservoirs are characterized by elevated breakdown pressures,diminished fracture complexity,and reduced modified volumes compared to medium and shallow ***,it is urgent to investigate particular injection strategies that can optimize breakdown pressure and fracturing efficiency to address the increasing demands for deep shale reservoir *** this study,the efficiency of various stimulation strategies,including multi-cluster simultaneous fracturing,modified alternating fracturing,alternating shut-in fracturing,and cyclic alternating fracturing,was ***,the sensitivity of factors such as the cycle index,shut-in time,cluster spacing,and horizontal permeability was ***,the flow distribution effect within the wellbore was *** results indicate that relative to multi-cluster simultaneous fracturing,modified alternating fracturing exhibits reduced susceptibility to the stress shadow effect,which results in earlier breakdown,extended hydraulic fracture lengths,and more consistent propagation despite an increase in breakdown *** alternating shut-in fracturing benefits the increase of fracture length,which is closely related to the shut-in ***,cyclic alternating fracturing markedly lowers breakdown pressure and contributes to uniform fracture propagation,in which the cycle count plays an important *** alternating fracturing demonstrates insensitivity to variations in cluster spacing,whereas horizontal permeability is a critical factor affecting fracture *** wellbore effect restrains the accumulation of pressure and flow near the perforation,delaying the initiation of hydraulic *** simulation results can provide valuable numerical insights for optimizing injection strategies for deep shale hydraulic fracturing.

关键词： Fracture propagation Numerical simulation Hydraulic fracturing Rock failure process analysis(RFPA) Injection strategy

Reaction pathways and selectivity in the chemo-catalytic conversion of cellulose and its derivatives to ethylene glycol:A review

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Chinese Journal of Chemical Engineering 2024年第2期66卷 310-331页

作者： yao Li Yuchun Zhang Zhiyu Li Huiyan Zhang Peng fu College of Agricultural Engineering and Food Science Shandong University of TechnologyZibo 255000China Key Laboratory of Energy Thermal Conversion and Control Ministry of EducationSchool of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Biomass-to-ethylene glycol is an effective means to achieve high-value utilisation of cellulose but is hindered by low conversion efficiency and poor catalyst activity and *** and cellobiose are derivatives of cellulose conversion to ethylene glycol,and it is found that studying the reaction process of both can help to understand the reaction mechanism of *** is desirable to develop a reusable,highly active catalyst to convert cellulose into ethylene *** ideal catalyst might have one or more active sites described the conversion steps ***,we discuss the catalyst development of celluloseto-ethylene glycol,including tungsten,tin,lanthanide,and other transition metal catalysts,and special attention is given to the reaction mechanism and kinetics for preparing ethylene glycol from cellulose,and the economic advantages of biomass-to-ethylene glycol are briefly *** insights given in this review will facilitate further development of efficient catalysts,for addressing the global energy crisis and climate change related to the use of fossil fuels.

关键词： Ethylene glycol Cellulose Catalyst Retro-aldol condensation Hydrolysis Kinetics

A continuous-wave Nd:YVO_(4)-KGW intracavity Raman laser with over 34% diode-to-Stokes optical efficiency

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High Power Laser Science and Engineering 2024年第2期12卷 62-68页

作者： Quan Sheng Jingni Geng Tianchang Liu Shijie fu Wei Shi Jianquan yao Institute of Laser and Optoelectronics School of Precision Instrument and Optoelectronics EngineeringTianjin UniversityTianjinChina Key Laboratory of Optoelectronic Information Technology(Ministry of Education) Tianjin UniversityTianjinChina

We demonstrate a continuous-wave(CW)Nd:YVO_(4)-potassium gadolinium tungstate(KGW)intracavity Raman laser with a diode-to-Stokes optical efficiency of 34.2%.By optimizing the cavity arrangement and reducing the cavity losses,8.47 W Stokes output at 1177 nm was obtained under an incident 878.6 nm diode pump power of 24.8 *** influence of cavity losses on the power and efficiency of the CW Raman laser,as well as the potential for further optimization,was investigated based on the numerical *** observation of thermally-induced output rollover was well explained by the calculation of the thermal lensing and cavity stability,indicating that the end-face curvature played an important role when the end-face of the crystal was highly reflective coated to make the cavity.A 10.9 W Stokes output under 40.9 W incident pump was also demonstrated with a cavity arrangement less sensitive to the end-face curvature,which is the highest output power of CW intracavity Raman lasers reported.

关键词： continuous wave intracavity Raman laser KGW crystal thermal lens

The preface: Interplay of topological and magnetic orders in the Mn-Bi-Te family

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National Science Review 2024年第2期11卷 6-7页

作者： fu-Chun Zhang hai-Zhou Lu X.C.Xie Kavli Institute for Theoretical Sciences University of Chinese Academy of Sciences Department of Physics Southern University of Science and Technology (SUSTech) International Center for Quantum Materials School of Physics Peking University

The discovery and synthesis of MnBi2Te4in 2013 initially garnered little attention [1]. Yet, the revelation of its topological properties in 2019 [2–6] sparked a surge of research into the MnBiTe family. These extensive studies are primarily driven by two objectives:the realization of a high-temperature quantum anomalous Hall effect （QAHE） and the exploration of exotic phases born from the interplay of topological and magnetic orders,

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Impact of metabolic syndrome components on clinical outcomes in hypertriglyceridemia-induced acute pancreatitis

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World Journal of Gastroenterology 2024年第35期30卷 3996-4010页

作者： Zhen-Hua fu Zi-Yue Zhao yao-Bing Liang Dong-Yu Cheng Jian-Ming Luo hai-Xing Jiang Shan-Yu Qin Department of Gastroenterology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND The incidence of hypertriglyceridemia(HTG)-induced acute pancreatitis(AP)is steadily increasing in China,becoming the second leading cause of *** complications and outcomes associated with HTG-AP are generally more severe than those seen in AP caused by other ***-AP is closely linked to metabolic dysfunction and frequently coexists with metabolic syndrome or its ***,the impact of metabolic syndrome components on HTGAP clinical outcomes remains *** To investigate the impact of metabolic syndrome component burden on clinical outcomes in *** In this retrospective study of 255 patients diagnosed with HTG-AP at the First Affiliated Hospital of Guangxi Medical University,we collected data on patient demographics,clinical scores,complications,and clinical ***,we analyzed the influence of the presence and number of individual metabolic syndrome components,including obesity,hyperglycemia,hypertension,and low high-density lipoprotein cholesterol(HDL-C),on the aforementioned parameters in HTG-AP *** This study found that metabolic syndrome components were associated with an increased risk of various complications in HTG-AP,with low HDL-C being the most significant risk factor for clinical *** risk of complications increased with the number of metabolic syndrome *** for age and sex,patients with highcomponent metabolic syndrome had significantly higher risks of renal failure[odds ratio(OR)=3.02,95%CI:1.12-8.11)],SAP(OR=5.05,95%CI:2.04-12.49),and intensive care unit admission(OR=6.41,95%CI:2.42-16.97)compared to those without metabolic *** The coexistence of multiple metabolic syndrome components can synergistically worsen the clinical course of HTGAP,making it crucial to monitor these components for effective disease management.

关键词： Hypertriglyceridemia-induced acute pancreatitis Metabolic syndrome High density lipoprotein cholesterol Obesity Hyperglycemia Hypertension Clinical outcomes

Recent Advances in Cobalt-Catalyzed Regio-or Stereoselective Hydrofunctionalization of Alkenes and Alkynes

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CCS Chemistry 2024年第5期6卷 1130-1156页

作者： Yan Li Xi Lu yao fu Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026 Key Laboratory of Precision and Intelligent Chemistry Department of Applied ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026

Hydrofunctionalization of alkenes and alkynes is increasingly important in preparing and modifying carbon-centered organic molecules such as pharmaceuticals,agrochemicals,andmaterial *** development of transition-metal-catalysts has revolutionized the hydrofunctionalization of unsaturated hydrocarbons,greatly improving the synthetic efficiency and selectivity of these *** recent years,notable progress has been achieved in low-cost metal-catalyzed alkene and alkyne hydrofunctionalization reactions following the utilization of traditional precious metal catalysts,including palladium,platinum,and ***-abundant cobalt catalysts,which are low in toxicity and exhibit unique reactivity and selectivity,are widely implemented in academic and industrial *** this review,we highlight recent examples of cobalt-catalyzed hydrofunctionalization of alkenes and alkynes to provide an overview of hydrofunctionalization methods,particularly hydroalkylation *** reactions greatly expand the scope and utility of cobalt-catalyzed couplings of carbon—carbon *** also highlight the mechanistic considerations and selective determinants *** hope our discussion will be informative for future developments in cobalt catalysis and hydrofunctionalization reactions.

关键词： hydrofunctionalization cobalt-catalysis alkene alkyne regioselectivity stereoselectivity