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Experimental research on the launching system of auxiliary charge with filter cartridge structure

Defence Technology（防务技术） 2024年第1期31卷 41-48页

作者： Zi-Jun Chen Ze He hong-hao Ma Lu-Qing Wang Zhao-Wu Shen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefeiAnhui230027PR China State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhui230026PR China

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile.The combustion chamber of the launching system is divided into two fixed chambers,one is located in the breech chamber,and the other is arranged in the barrel.The breech chamber charge was ignited first,and the charges in the auxiliary chambers were ignited by the high-temperature,highpressure combustible gas trailing the projectile.In this way,the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the projectile.The proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the chamber.In order to obtain some internal ballistic characteristics of the launch system,some critical structure,such as the length of the filter cartridge auxiliary charge,the combustion degree of the propellant in the chamber,and the length of the barrel,are discussed.The experimental results show that with the increased auxiliary charge length,a pressure plateau or even a secondary peak pressure can be formed,which is less than the peak pressure.The projectile velocity increased by 23.57%,14.64%,and 7.65%when the diaphragm thickness was 0 mm,1 mm,and2 mm,respectively.The muzzle velocity of the projectile can be increased by 13.42%by increasing the length of the barrel.Under the same charge condition,with the increase of barrel length,the energy utilization rate of propellant increases by 28.64%.

关键词： Interior ballistics Charge structures Launch system Charge design

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Numerical investigation of the failure mechanism of cubic concrete specimens in SHPB tests

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Defence Technology（防务技术） 2022年第1期18卷 1-11页

作者： Mei Li hong hao Jian Cui Yi-fei hao Labomtory of Coast Civil Structure Safety of Ministry of Education Tianjin UniversityTiarjin300072China chool of Civil Engineering.Tianin University Tianjin300072China entre for Infrastructural Monitoring and Protection School of Civil and Mechanical Engineering Curtin UniversityPerth Western Australia6845Australia

Cylindrical specimens are commonly used in Split Hopkinson pressure bar(SHPB)tests to study the uniaxial dynamic properties of concrete-like materials.In recent years,true tri-axial SHPB equipment has also been developed or is under development to investigate the material dynamic properties under tri-axial impact loads.For such tests,cubic specimens are needed.It is well understood that static material strength obtained from cylinder and cube specimens are different.Conversion factors are obtained and adopted in some guidelines to convert the material streng th obtained from the two types of specimens.Previous uniaxial impact tests have also demonstrated that the failure mode and the strain rate effect of cubic specimens are very different from that of cylindrical ones.However,the mechanical background of these findings is unclear.As an extension of the previous laboratory study,this study performs numerical SHPB tests of cubic and cylindrical concrete specimens subjected to uniaxial impact load with the validated numerical model.The stress states of cubic specimens in relation to its failure mode under different strain rates is analyzed and compared with cylindrical specimens.The detailed analyses of the numerical simulation results show that the lateral inertial confinement of the cylindrical specimen is higher than that of the cubic specimen under the same strain rates.For cubic specimen,the corners aremore severely damaged because of the lower lateral confinement and the occurrence of the tensile radial stress which is not observed in cylindrical specimens.These results explain why the dynamic material strengths obtained from the two types of specimens are different and are strain rate dependent.Based on the simulation results,an empirical formula of conversion factor as a function of strain rate is proposed,which supplements the traditional conversion factor for quasi-static material strength.It can be used for transforming the dynamic compressive strength from cylinders to cubes obtained from impact tests a

关键词： Concrete Lateral inertial confinement Shape effet Dynamic failure mechanism Strain rate

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Numerical prediction of ground vibrations induced by LPG boiling liquid expansion vapour explosion(BLEVE)inside a road tunnel

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Underground Space 2023年第5期12卷 44-64页

作者： Ruishan Cheng Wensu Chen hong hao Jingde Li Center for Infrastructural Monitoring and Protection School of Civil and Mechanical EngineeringCurtin UniversityBentley 6102Australia Earthquake Engineering Research&Test Center Guangzhou UniversityGuangzhou 510006China

Accidental boiling liquid expansion vapour explosions(BLEVEs)caused by the bursting of liquified petroleum gas(LPG)tank inside a tunnel can induce vibrations of its surrounding geological media and threaten the stability of adjacent tunnels and structures.Therefore,it is essential to understand the characteristics of vibrations induced by LPG BLEVEs inside the tunnel for the safety design of its adjacent structures.Owing to the difficulty in effectively predicting the LPG BLEVE loads,the current practice usually employs equivalent methods,e.g.,the TNT-equivalency method,in LPG BLEVE load predictions for structural response analysis,which may lead to inaccurate response predictions.This study compares ground vibrations induced by a BLEVE inside an arched road tunnel with those induced by its equivalent TNT explosion via high-fidelity numerical simulations.The results demonstrate that the frequency of BLEVEinduced vibrations is lower than that induced by the TNT explosion at the same scaled distance.The intensity of LPG BLEVE-induced vibrations at relatively small-scaled distances is lower than that of TNT explosion-induced vibrations at the same scaled distance,but becomes higher after a certain scaled distance because of the relatively low attenuation rate.In addition,parametric analysis is conducted to evaluate the effects of various factors on the characteristics of LPG BLEVE-induced ground vibrations.It is found that the surrounding rock type,the rock porosity,and the cover depth of the tunnel have more significant influences than the concrete grade of the tunnel lining.The recommendation for the tunnel design is also given based on the intensity and frequency characteristics of BLEVE-induced vibrations.

关键词： Tunnel BLEVE TNT explosion Vibration intensity Vibration frequency

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Numerical study on dynamic properties of rubberised concrete with different rubber contents

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Defence Technology（防务技术） 2023年第6期24卷 228-240页

作者： Lei Pan hong hao Jian Cui Thong M.Pham Guangzhou University-Curtin University Joint Research Centre for Structural Monitoring and Protection Against Multi-Dynamic Hazards School of Civil EngineeringGuangzhou UniversityChina Guangzhou University-Curtin University Joint Research Centre for Structural Monitoring and Protection Against Multi-Dynamic Hazards School of Civil and Mechanical EngineeringCurtin UniversityAustralia School of Civil Engineering Tianjin UniversityChina Centre for Infrastructural Monitoring and Protection School of Civil and Mechanical EngineeringCurtin UniversityAustralia

As a green environmentally-friendly material,rubberised concrete(Ru C),which has the characteristics of low elastic modulus,large deformation capacity,high damping,good energy dissipation and good crack resistance,has attracted extensive attention and research in the civil engineering discipline.However,most of existing studies are based on experimental tests on Ru C material properties,and there has been no numerical study based on meso-scale modelling of Ru C yet.To more comprehensively investigate the Ru C dynamic material properties without conducting intensive experimental tests,this study developed a high-fidelity meso-scale model considering coarse and fine aggregates and rubber crumbs to numerically investigate the mechanical properties of rubberised concrete under different strain rates.The meso-scale model was verified against both quasi-static compressive testing data and Split Hopkinson Pressure Bar(SHPB)dynamic testing data.Using the verified numerical model,the dynamic properties of rubberised concrete with various rubber content(0%-30%)under different strain rates were studied.The numerical results show that the developed meso-scale model can use to predict the static and dynamic properties of rubberised concrete with high accuracy.The dynamic compressive strength of the rubberised concrete increases with the increment of the strain rate,and the strain rate sensitivity increases with the rubber content ranging from 0 to 30%.Based on intensive numerical simulation data,empirical DIFs is used as a function of strain rate and rubber content to predict the dynamic strength of rubberised concrete.

关键词： Rubberised concrete Meso-scale model Numerical simulation Strain rate effect Dynamic increase factor

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Microbiota–gut–brain axis and its therapeutic applications in neurodegenerative diseases

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Signal Transduction and Targeted Therapy 2024年第3期9卷 945-997页

作者： Jian Sheng Loh Wen Qi Mak Li Kar Stella Tan Chu Xin Ng hong hao Chan Shiau Hueh Yeow Jhi Biau Foo Yong Sze Ong Chee Wun How Kooi Yeong Khaw School of Pharmacy Monash University MalaysiaJalan Lagoon Selatan47500 Bandar SunwaySelangorMalaysia School of Pharmacy Faculty of Health&Medical SciencesTaylor’s University1Jalan TaylorsSubang Jaya 47500 SelangorMalaysia Digital Health&Medical Advancements Taylor’s University1Jalan TaylorsSubang Jaya 47500 SelangorMalaysia School of Biosciences Faculty of Health&Medical SciencesTaylor’s University1Jalan TaylorsSubang Jaya 47500 SelangorMalaysia UCL School of Pharmacy University College London29-39 Brunswick SquareLondon WC1N 1AXUK

The human gastrointestinal tract is populated with a diverse microbial community.The vast genetic and metabolic potential of the gut microbiome underpins its ubiquity in nearly every aspect of human biology,including health maintenance,development,aging,and disease.The advent of new sequencing technologies and culture-independent methods has allowed researchers to move beyond correlative studies toward mechanistic explorations to shed light on microbiome–host interactions.Evidence has unveiled the bidirectional communication between the gut microbiome and the central nervous system,referred to as the“microbiota–gut–brain axis”.The microbiota–gut–brain axis represents an important regulator of glial functions,making it an actionable target to ameliorate the development and progression of neurodegenerative diseases.In this review,we discuss the mechanisms of the microbiota–gut–brain axis in neurodegenerative diseases.As the gut microbiome provides essential cues to microglia,astrocytes,and oligodendrocytes,we examine the communications between gut microbiota and these glial cells during healthy states and neurodegenerative diseases.Subsequently,we discuss the mechanisms of the microbiota–gut–brain axis in neurodegenerative diseases using a metabolite-centric approach,while also examining the role of gut microbiota-related neurotransmitters and gut hormones.Next,we examine the potential of targeting the intestinal barrier,blood–brain barrier,meninges,and peripheral immune system to counteract glial dysfunction in neurodegeneration.Finally,we conclude by assessing the pre-clinical and clinical evidence of probiotics,prebiotics,and fecal microbiota transplantation in neurodegenerative diseases.A thorough comprehension of the microbiota–gut–brain axis will foster the development of effective therapeutic interventions for the management of neurodegenerative diseases.

关键词： degenerative therapeutic diseases

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坚持和发展民主集中制原则推进新时代中国刑事诉讼制度现代化

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政法论丛 2024年第1期 37-52页

作者：洪浩武汉大学法学院湖北武汉430072

全国人大已将《刑事诉讼法》的修改列入本届人大的工作规划之中。作为规范刑事诉讼程序、约束诉讼主体行为的基本法律,应该明确刑事诉讼中公权力机关之间职能分工的工作原则。民主集中制是我国《宪法》规定的国家机构组织和活动原则,同... 详细信息

全国人大已将《刑事诉讼法》的修改列入本届人大的工作规划之中。作为规范刑事诉讼程序、约束诉讼主体行为的基本法律,应该明确刑事诉讼中公权力机关之间职能分工的工作原则。民主集中制是我国《宪法》规定的国家机构组织和活动原则,同时也是我国现行刑事诉讼确立的公权力机关之间职能分工的指导原则,具体表现为公检法等机关在刑事诉讼中“分工负责、互相配合、互相制约”的工作原则。民主集中制决定了我国刑事诉讼中权力的集中本位及其分工的相对性。新时代应该发展刑事诉讼中的民主集中制原则,顺应权力本位向权利本位转变的时代潮流,以实现民主集中制原则与刑事诉讼制度的根本自洽,推进刑事诉讼现代化。

关键词：刑事诉讼权力分工权力本位权利本位司法民主

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Potentiation of the lateral habenula-ventral tegmental area pathway underlines the susceptibility to depression in mice with chronic pain

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Science China(Life Sciences) 2024年第1期67卷 67-82页

作者： Chun-Kui Zhang Pan Wang Yuan-Yuan Ji Jian-Shuai Zhao Jun-Xiang Gu Xian-Xia Yan hong-Wei Fan Ming-Ming Zhang Yu Qiao Xiao-Die Liu Bao-Juan Li Ming-Hui Wang Hai-Long Dong hao-hong Li Peng-Cheng Huang Yun-Qing Li Wu-Gang Hou Jin-Lian Li Tao Chen Department of Anatomy and K.K.Leung Brain Research Centre Fourth Military Medical UniversityXi’an 710032China Beijing Institute of Basic Medical Sciences Beijing 100850China Key Laboratory of Ministry of Public Health for Forensic Science Xi’an Jiaotong UniversityXi’an 710061China Department of Anesthesiology Xijing HospitalFourth Military Medical UniversityXi’an 710032China Department of Neurosurgery the Second Affiliated Hospital of Xian Jiaotong UniversityXi’an 710004China School of Biomedical Engineering Fourth Military Medical UniversityXi’an 710032China Affiliated Mental Health Centre and Hangzhou Seventh People’s Hospital Zhejiang University School of MedicineHangzhou 310013China The MOE Frontier Research Center of Brain&Brain-machine Integration Zhejiang University School of Brain Science and Brain MedicineHangzhou 310058China Department of Neurology The First Affiliated Hospital of Nanchang UniversityNanchang 330006China Department of Anatomy School of MedicineNorthwest UniversityXi’an 710069China

Chronic pain often develops severe mood changes such as depression.However,how chronic pain leads to depression remains elusive and the mechanisms determining individuals’responses to depression are largely unexplored.Here we found that depression-like behaviors could only be observed in 67.9%of mice with chronic neuropathic pain,leaving 32.1%of mice with depression resilience.We determined that the spike discharges of the ventral tegmental area(VTA)-projecting lateral habenula(LHb)glutamatergic(Glu)neurons were sequentially increased in sham,resilient and susceptible mice,which consequently inhibited VTA dopaminergic(DA)neurons through a LHbGlu-VTAGABA-VTADA circuit.Furthermore,the LHbGlu-VTADA excitatory inputs were dampened via GABAB receptors in a pre-synaptic manner.Regulation of LHb-VTA pathway largely affected the development of depressive symptoms caused by chronic pain.Our study thus identifies a pivotal role of the LHb-VTA pathway in coupling chronic pain with depression and highlights the activity-dependent contribution of LHbGlu-to-VTADA inhibition in depressive behavioral regulation.

关键词： chronic pain depression lateral habenula ventral tegmental area dopamine susceptibility

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Biomimetic natural biomaterials for tissue engineering and regenerative medicine:new biosynthesis methods,recent advances,and emerging applications

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Military Medical Research 2024年第1期11卷 50-79页

作者： Shuai Liu Jiang-Ming Yu Yan-Chang Gan Xiao-Zhong Qiu Zhe-Chen Gao Huan Wang Shi-Xuan Chen Yuan Xiong Guo-Hui Liu Si-En Lin Alec McCarthy Johnson V.John Dai-Xu Wei hong-hao Hou Guangdong Provincial Key Laboratory of Construction and Detection in Tissue Engineering the Fifth Affiliated HospitalSchool of Basic Medical ScienceSouthern Medical UniversityGuangzhou 510900China Department of Orthopedics Tongren HospitalShanghai Jiao Tong UniversityShanghai 200336China The Eighth Affiliated Hospital Sun Yat-Sen UniversityShenzhen 518033GuangdongChina Engineering Research Center of Clinical Functional Materials and Diagnosis&Treatment Devices of Zhejiang Province Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhou 325011ZhejiangChina Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Orthopaedics and Traumatology Faculty of Medicinethe Chinese University of Hong KongHong Kong SAR 999077China Department of Functional Materials Terasaki Institute for Biomedical InnovationLos AngelesCA 90064USA Mary&Dick Holland Regenerative Medicine Program College of MedicineUniversity of Nebraska Medical CenterOmahaNE 68130USA Zigong Affiliated Hospital of Southwest Medical University Zigong Psychiatric Research CenterZigong Institute of Brain ScienceZigong 643002SichuanChina Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of EducationSchool of MedicineDepartment of Life Sciences and MedicineNorthwest UniversityXi’an 710127China

Biomimetic materials have emerged as attractive and competitive alternatives for tissue engineering(TE)and regenerative medicine.In contrast to conventional biomaterials or synthetic materials,biomimetic scaffolds based on natural biomaterial can offer cells a broad spectrum of biochemical and biophysical cues that mimic the in vivo extracellular matrix(ECM).Additionally,such materials have mechanical adaptability,micro-structure interconnectivity,and inherent bioactivity,making them ideal for the design of living implants for specific applications in TE and regenerative medicine.This paper provides an overview for recent progress of biomimetic natural biomaterials(BNBMs),including advances in their preparation,functionality,potential applications and future challenges.We highlight recent advances in the fabrication of BNBMs and outline general strategies for functionalizing and tailoring the BNBMs with various biological and physicochemical characteristics of native ECM.Moreover,we offer an overview of recent key advances in the functionalization and applications of versatile BNBMs for TE applications.Finally,we conclude by offering our perspective on open challenges and future developments in this rapidly-evolving field.

关键词： Biomimic Scaffold Biosynthesis Natural biomaterial Tissue engineering

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Wnt/β-catenin signaling is involved in the Icariin induced proliferation of bone marrow mesenchymal stem cells

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Journal of Traditional Chinese Medicine 2016年第3期36卷 360-368页

作者： Fu Shuping Yang Li hong hao Zhang Ronghua Key Laboratory of Acupuncture and Medicine Research of Minister of Education Nanjing University of Chinese Medicine College of Pharmacy Jinan Univeristy

OBJECTIVE: To investigate the effect of icariin on proliferation of bone marrow mesenchymal stem cells(BMSCs) in Sprague-Dawley(SD) rats.METHODS: BMSCs were obtained from SD rat bone marrow with differential time adherent method. Its characteristic was identified through differentiation cell surface antigens and the multi-lineage(osteo/adipo/chondo) differentiation potential. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) method and 5-Bromo-2-Deoxyuridine(Brd U) incorporation were applied to detect the effect of icariin on BMSCs proliferation.Flow cytometry was used to detect proliferation in-dex of BMSCs. The m RNA level and the distribution of β-catenin were evaluated by Real-time Polymerase Chain Reaction(PCR) and Immunofluorescent staining respectively. Western blot was used to detect protein expression levels of β-catenin, glycogen synthase kinase-3 beta(GSK-3β), phospho-glycogen synthase kinase-3 beta(p GSK-3β)and cyclin D1.RESULTS: Icariin promoted BMSCs proliferation at the concentration of 0.05-2.0 mg/L. The percentage of Brd U positive cells of BMSCs was increased from40.98% to 70.42%, and the proliferation index value was increased from 8.9% to 17.5% with the treatment of 0.05 mg/L icariin, which significance values were both less than 0.05. Compared with the control group, total and nuclear β-catenin proteins, as well as β-catenin m RNA expression, were all increased with icariin treatment. Meanwhile, the phosphorylation level of GSK-3β and cyclin D1 protein expressions were also increased in BMSCs with icariin treatment.CONCLUSION: The findings of the present study demonstrated that low dosage of icariin could promote BMSCs proliferation. The activation of Wnt/β-catenin pathways was involved in this process.

关键词：骨髓间充质干细胞 β-catenin Wnt信号通路淫羊藿苷细胞增殖 Sprague-Dawley 诱导免疫荧光染色

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Response of a transmission tower-line system at a canyon site to spatially varying ground motions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第2期12卷 103-120页

作者： hong-nan LI Feng-long BAI Li TIAN hong hao State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China Sehool of Civil and Resource Engineering University of Western Australia WA 6009 Australia

Collapses of transmission towers were often observed in previous large earthquakes such as the Chi-Chi earthquake in Taiwan and Wenchuan earthquake in Sichuan,China. These collapses were partially caused by the pulling forces from the transmission lines generated from out-of-phase responses of the adjacent towers owing to spatially varying earthquake ground motions. In this paper,a 3D finite element model of the transmission tower-line system is established considering the geometric nonlinearity of transmission lines. The nonlinear responses of the structural system at a canyon site are analyzed subjected to spatially varying ground motions. The spatial variations of ground motion associated with the wave passage,coherency loss,and local site effects are given. The spatially varying ground motions are simulated stochastically based on an empirical coherency loss function and a filtered Tajimi-Kanai power spectral density function. The site effect is considered by a transfer function derived from 1D wave propagation theory. Compared with structural responses calculated using the uniform ground motion and delayed excitations,numerical results indicate that seismic responses of transmission towers and power lines are amplified when considering spatially varying ground motions including site effects. Each factor of ground motion spatial variations has a significant effect on the seismic response of the structure,especially for the local site effect. Therefore,neglecting the earthquake ground motion spatial variations may lead to a substantial underestimation of the response of transmission tower-line system during strong earthquakes. Each effect of ground motion spatial variations should be incorporated in seismic analysis of the structural system.

关键词： Transmission tower-line system Canyon site Spatially varying ground motions Coherency loss Local site effect

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