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Defence Technology（防务技术） 2024年第1期31卷 230-241页

作者： junbao Li Weibing Li Xiaoming Wang ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing 210094China

This study proposed three types of Al—Hf reactive materials with particle size ratios(a),which were almost completely dense(porosity of<5.40%)owing to their preparation using hot-pressing technology.Microstructure ch... 详细信息

This study proposed three types of Al—Hf reactive materials with particle size ratios(a),which were almost completely dense(porosity ofdually increased with increasing a,and a small amount of fine Hf appeared for the sample with a=1.The reactive materials exhibited clear strain-rate sensitivity,with flow stressσ0.05and failure strainεfincreasing approximately linearly with increasing strain rate.ε.It is found that the plastic deformation of the material increased with increasing strain rate.As a increased from 0.1 to 1,the flow stress gradually increased.Impact failure of the material was dominated by ductile fracture with a large Al phase plastic deformation band for lower a,while brittle fracture with crushed Hf particles occurred at higher a.Finally,a constitutive model based on BP neural network was proposed to describe the stress-strain relationships of the materials,with an average relative error of 2.22%.

关键词： Reactive material Particle size Split Hopkinson pressure bar test Stressestrain relationship Impact failure BP neural network

Sitting intolerance:A new disease entity in children and adolescents

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Pediatric Investigation 2022年第4期6卷 299-301页

作者： Yumeng Gao Hongfang Jin junbao du Department of Pediatrics Peking University First HospitalBeijingChina Key Laboratory of Molecular Cardiovascular Sciences Ministry of EducationBeijingChina

Sitting intolerance refers to a series of symptoms(e.g.,dizziness,headache,blurred vision,chest tightness,nausea,abdominal pain,numbness,and syncope)induced by sedentariness or a sudden transition from a supine position to a sitting position.1,2 Many investigations regarding the pathogenesis,clinical manifestation,diagnosis,and treatment of orthostatic intolerance have been conducted in recent years,but little is known about these issues with respect to sitting intolerance among children and adolescents.Notably,sitting syncope is not rare among adults with a history of syncope.In a study of 111 adult patients,Khadilkar et al.

关键词： intolerance adolescent diagnosis

Progress in the application of polymer fibers in solid electrolytes for lithium metal batteries

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Journal of Energy Chemistry 2024年第5期92卷 26-42页

作者： junbao Kang Nanping Deng Bowen Cheng Weimin Kang State Key Laboratory of Separation Membranes and Membrane Processes/National Center for International Joint Research on Separation Membranes School of Textile Science and EngineeringTiangong UniversityTianjin 300387China

Solid state lithium metal batteries(SSLMBs)are considered to be one of the most promising battery systems for achieving high energy density and excellent safety for energy storage in the future.However,current existed solid-state electrolytes(SSEs)are still difficult to meet the practical application requirements of SSLMBs.In this review,based on the analysis of main problems and challenges faced by the development of SSEs,the ingenious application and latest progresses including specific suggestions of various polymer fibers and their membrane products in solving these issues are emphatically reviewed.Firstly,the inherent defects of inorganic and organic electrolytes are pointed out.Then,the application strategies of polymer fibers/fiber membranes in strengthening strength,reducing thickness,enhancing thermal stability,increasing the film formability,improving ion conductivity and optimizing interface stability are discussed in detail from two aspects of improving physical structure properties and electrochemical performances.Finally,the researches and development trends of the intelligent applications of high-performance polymer fibers in SSEs is prospected.This review intends to provide timely and important guidance for the design and development of polymer fiber composite SSEs for SSLMBs.

关键词： Composite solide lectrolytes Polymer fibers Solid-state lithium metal batteries Solid-stateel ectrolytes Nanofiber membranes

Fatigue properties and damage constitutive model of salt rock based on CT scanning

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International Journal of Mining Science and Technology 2024年第2期34卷 245-259页

作者： junbao Wang Xiao Liu Qiang Zhang Xinrong Liu Zhanping Song Shijin Feng College of Civil Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Key Lab of Geotechnical and Underground Space Engineering Xi’an 710055China School of Civil Engineering Chongqing UniversityChongqing 400045China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

To investigate the macroscopic fatigue properties and the mesoscopic pore evolution characteristics of salt rock under cyclic loading,fatigue tests under different upper-limit stresses were carried out on salt rock,and the mesoscopic pore structures of salt rock before and after fatigue tests and under different cycle numbers were measured using CT scanning instrument.Based on the test results,the effects of the cycle number and the upper-limit stress on the evolution of cracks,pore morphology,pore number,pore volume,pore size,plane porosity,and volume porosity of salt rock were analyzed.The failure path of salt rock specimens under cyclic loading was analyzed using the distribution law of plane porosity.The damage variable of salt rock under cyclic loading was defined on basis of the variation of volume porosity with cycle number.In order to describe the fatigue deformation behavior of salt rock under cyclic loading,the nonlinear Burgers damage constitutive model was further established.The results show that the model established can better reflect the whole development process of fatigue deformation of salt rock under cyclic loading.

关键词： Salt rock Cyclic loading CT scanning Mesoscopic pore evolution Constitutive model

Pathophysiology and Individualized Management of Vasovagal Syncope and Postural Tachycardia Syndrome in Children and Adolescents:An Update

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Neuroscience Bulletin 2020年第6期36卷 667-681页

作者： Ying Liao junbao du Department of Pediatrics Peking University First HospitalBeijing 100034China

Vasovagal syncope(VVS) and postural tachycardia syndrome(POTS) are the main forms of orthostatic intolerance in pediatrics and both are underlying causes of neurally-mediated syncope.In recent years,increasing attention has been paid to the management of VVS and POTS in children and adolescents.A number of potential mechanisms are involved in their pathophysiology,but the leading cause of symptoms varies among patients.A few studies thus have focused on the individualized treatment of VVS or POTS based on selected hemodynamic parameters or biomarkers that can predict the therapeutic effect of certain therapies and improve their effectiveness.This review summarizes the latest developments in individualized treatment of VVS and POTS in children and indicates directions for further research in this field.

关键词： Vasovagal syncope Postural tachycardia syndrome Individualized management Pathophysiology Children Adolescents

Flexible Fixture Design for the Top and End Surface Processing of NP2_NP4 Cylinder Heads

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Journal of Electronic Research and Application 2024年第3期8卷 20-27页

作者： Cheng Chang junbao Chen College of Mechanical Engineering Hubei University of Automotive TechnologyShiyan 442002Hubei ProvinceChina

This paper focuses on the design of fixtures for NP2 and NP4 cylinder heads on a horizontal machining center of flexible machining automatic lines.It began with an analysis of the diagrams of part processing and working procedure which formed the basis for the design of the processing technology scheme,a selection of suitable machine tools,and the setting of processing parameters.Fixtures tailored to the chosen machine tools were then designed to meet the processing requirements.Additional aspects of the project included the design of part drawings,calculation of working time quota,design of auxiliary guides,support clamping,and hydraulic circuits,all aimed at fulfilling practical production requirements.

关键词： Part processing technology analysis Calculation of working time quota Fixture design

Orthostatic Intolerance and Coagulation Abnormalities:An Update

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Neuroscience Bulletin 2019年第1期35卷 171-177页

作者： Wei Quan Yuchen Wang Selena Chen junbao du Department of Pediatrics Peking University First Hospital Department of Clinical Medicine Peking University Health Science Center Department of Biochemistry and Cellular Biology University of California at San Diego Key Laboratory of Molecular Cardiovascular Science of the Ministry of Education

Orthostatic intolerance(OI)is a series of clinical symptoms that develop during long-term standing in the upright position,with clinical manifestations of frequent,recurrent,or persistent dizziness,fatigue,and heart p... 详细信息

关键词： HUT Hg Orthostatic Intolerance and Coagulation Abnormalities:An Update vWF

RuO_(2)/TiO_(2)/MXene with multi-heterojunctions coating on carbon cloth for high-activity chlorine evolution reaction at large current densities

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Nano Research 2024年第6期17卷 4764-4772页

作者： Yuhao duan Liuxu Wei Chenyu Cai junbao Mi Fuyuan Cao Jiaze Chen Xiaolong Li Xiujiang Pang Bin Li Lei Wang Key Laboratory of Eco-chemical Engineering Ministry of EducationInternational Science and Technology Cooperation Base of Eco-chemical Engineering and Green ManufacturingCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China College of Environment and Safety Engineering Qingdao University of Science and TechnologyQingdao 266042China

The chlorine evolution reaction(CER)is a crucial step in the production of chlorine gas and active chlorine by chlor-alkali electrolysis.Currently,the endeavor to fabricate electrodes capable of yielding high current density at minimal overpotential remains a central challenge in advancing the realm of chlorine evolution reactions.Here,we grow TiO_(2)and RuO_(2)on MXene@carbon cloth(CC)through the favorable affinity and induced deposition effect between the surface functional groups of MXene and the metal.A self-supported electrode(RuTiO_(2)/MXene@CC)with strong binding at the electrocatalyst-support interface and weak adhesion at electrocatalyst-bubble interface is constructed.The RuTiO_(2)/MXene@CC can reduce the electron density of RuO_(2)by regulating the electron redistribution at the heterogeneous interface,thus enhancing the adsorption of Cl−.RuTiO_(2)/MXene@CC could achieve a high current density of 1000 mA·cm^(−2)at a small overpotential of 220 mV,superior to commercial dimensionally stable anodes(DSA).This study provides a new strategy for constructing efficient CER catalysts at high current density.

关键词： chlorine evolution reaction high current density MXene TiO_(2) RuO_(2)

Kawasaki disease shock syndrome: A report of two cases and literature review

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Pediatric Investigation 2019年第2期3卷 81-85页

作者： Qingyou Zhang Ying Liao junbao du Department of Pediatrics Peking University First HospitalBering 100034China

Importance:Kawasaki disease shock syndrome (KDSS) is a rare Kawasaki disease (KD) manifestation.The pediatricians are not aware of the full range of clinical characteristics of KDSS.Objective:We aimed to investigate the clinical features,diagnosis and treatment of KDSS in two patients and we included a literature review.Methods:We collected and analyzed the clinical data for two patients with KDSS.Additionally,using 'Kawasaki diseases shock syndrome' as a key phrase,we searched PubMed,Biotechnology Information and Wanfang Data Knowledge Service Platform databases for any similar reports between January 2009 and March 2017.Results:Both of our patients diagnosed with KD developed sustained hypotension during the course of intravenous immunoglobulin treatment,as well as hypoalbuminemia,and increased C-reactive protein and brain natriuretic peptide levels during hypotension.Both patients responded well to fluid resuscitation and inotropic support.No aneurysms formed in either patient during follow-up.We reviewed two related studies in Chinese and 11 studies in English.Interpretation:KD may present with severe shock,and requires proper diagnosis and rapid treatment.The prognosis for most patients with KDSS is excellent.

关键词： Brain natriuretic peptide Children Kawasaki disease Shock

Autonomic Nervous Function in Vasovagal Syncope of Children and Adolescents

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Neuroscience Bulletin 2019年第5期35卷 937-940页

作者： Chunyan Tao Chaoshu Tang Selena Chen Hongfang Jin junbao du Department of Pediatrics Peking University First Hospital Beijing 100034 China Department of Physiology and Pathophysiology Peking University Health Sciences Centre Beijing 100191 China Division of Biological Sciences University of California San Diego CA 92093 USA Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education of China Beijing 100191 China

Syncope is defined as a transient loss of consciousness due to global cerebral hypoperfusion, accompanied by loss of muscle tone and failure to maintain an active position. Vasovagal syncope (VVS) is the most common presentation of syncope, and its diagnostic criteria include:(1) absence of any other evident etiology for syncope or presyncope,(2) positive response to head-up tilt test with evident vasovagal reaction (hypotension and/or bradycardia), and (3) no concomitant chronic or acute disease [1, 2]. The onset of VVS peaks initially in childhood and adolescence, and accounts for 60%–70% of all syncopal cases. Clinicians pay great attention to syncope among children and adolescents, due to its high prevalence and its impact on patients’ quality of life. Affected individuals often experience mental stress, economic burdens, and accidental bodily injuries related to syncope [2]. While the pathogenesis of VVS is not fully understood, autonomic nervous dysfunction has been identified as a contributing mechanism. The examination of autonomic nervous function can provide important information about patients with syncope.

关键词： Autonomic Nervous Function Vasovagal Syncope Children Adolescents