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Response characteristics of gas pressure under simultaneous static and dynamic load:Implication for coal and gas outburst mechanism

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International Journal of Mining Science and Technology 2023年第2期33卷 155-171页

作者： Longyong Shu Liang Yuan Qixian Li wentao xue Nannan Zhu Zhengshuai Liu School of Energy and Mining Engineering China University of Mining and Technology-BeijingBeijing 100083China Mine Safety Technology Branch China Coal Research InstituteBeijing 100013China State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science&TechnologyHuainan 232001China China Coal Research Institute Beijing 100013China

Coal and gas outbursts are dynamic disasters in which a large mass of gas and coal suddenly emerges in a mining space within a split second.The interaction between the gas pressure and stress environment is one of the key factors that induce coal and gas outbursts.In this study,first,the coupling relationship between the gas pressure in the coal body ahead of the working face and the dynamic load was investigated using experimental observations,numerical simulations,and mine-site investigations.It was observed that the impact rate of the dynamic load on the gas-bearing coal can significantly change the gas pressure.The faster the impact rate,the speedier the increase in gas pressure.Moreover,the gas pressure rise was faster closer to the impact interface.Subsequently,based on engineering background,we proposed three models of stress and gas pressure distribution in the coal body ahead of the working face:static load,stress disturbance,and dynamic load conditions.Finally,the gas pressure distribution and outburst mechanism were investigated.The high concentration of gas pressure appearing at the coal body ahead of the working face was caused by the dynamic load.The gas pressure first increased gradually to a peak value and then decreased with increasing distance from the working face.The increase in gas pressure plays a major role in outburst initiation by resulting in the ability to more easily reach the critical points needed for outburst initiation.Moreover,the stronger the dynamic load,the greater the outburst initiation risk.The results of this study provide practical guidance for the early warning and prevention of coal and gas outbursts.

关键词： Coal and gas outburst Gas pressure Dynamic load Outburst mechanism

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Short communication:Extreme glacier mass loss triggered by high temperature and drought during hydrological year 2022/2023 in Qilian Mountains

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Research in Cold and Arid Regions 2024年第1期16卷 1-4页

作者： JiZu Chen XingYu xue wentao Du State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences(CAS)LanzhouGansu 730000China Gansu Provincial Industry Technology Center of Intelligent Equipment and Big Data for Disaster Prevention Northwest Institute of Eco-Environment and ResourcesChinese Academy of Science(CAS)LanzhouGansu 730000China Zhangye Meteorological Bureau ZhangyeGansu 734000China College of Resources and Environment University of Chinese Academy of Sciences(UCAS)Beijing 100049China

In the hydrological year 2022/2023,the glaciers in the Qilian Mountains experienced unprecedented mass loss.The glacier-wide mass balance was-1,188 mm w.e.,in contrast to-350 mm of average mass balance since 1990 over the Bailanghe Glacier No.12 in the middle of Qilian Mountains.The temperature during 2022–2023 reached the highest value ever recorded,second only to 2022,while at the same time the precipitation amount was less compared to other year since 2000,which together led to the strongest glacier mass loss during 2022–2023.The atmospheric circulation analysis shows that the high temperature in the Qilian Mountains in 2023 was jointly caused by the Arctic air mass and East Asian monsoon.

关键词： Bailanghe Glacier No.21 Glacier mass loss Extreme high temperature Atmospheric circulation

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Arbuscular mycorrhizal fungi inoculation and exogenous indole-3-acetic acid application induce antioxidant defense response to alleviate cadmium toxicity in Broussonetia papyrifera

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Pedosphere 2024年第2期34卷 447-459页

作者： xue LI Jingwei LIANG Hongjian WEI Yuxuan KUANG Hui CHEN Ming TANG wentao HU State Key Laboratory of Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory for Lingnan Modern AgricultureGuangdong Key Laboratory for Innovative Development and Utilization of Forest Plant GermplasmCollege of Forestry and Landscape ArchitectureSouth China Agricultural UniversityGuangzhou 510642China

Cadmium(Cd)contamination in soil poses a huge threat to plants even at low concentrations;Broussonetia papyrifera has great potential in remediation of soil heavy metal contamination.However,whether exogenous indole-3-acetic acid(IAA)application and arbuscular mycorrhizal fungi(AMF)have synergistic effects on Cd tolerance of B.papyrifera remains unclear.To investigate the effects of AMF inoculation and IAA application on the tolerance of B.papyrifera to Cd stress,two experiments were conducted:the first to investigate the effect of AMF(Rhizophagus irregularis)inoculation on the tolerance of B.papyrifera to Cd stress and the second to investigate the combined effects of AMF inoculation and IAA application on the tolerance of B.papyrifera to Cd stress.Parameters including endogenous hormone concentration,antioxidant defense response,malondialdehyde(MDA)content,and gene expression related to antioxidant enzyme system and hormone were measured.The results indicated that AMF alleviated Cd toxicity of B.papyrifera by reducing MDA content and improving antioxidant enzyme activities and Cd absorption capacity.Furthermore,the combination of AMF inoculation and IAA application had a synergetic effect on the tolerance of B.papyrifera to Cd stress through upregulating BpAUX1 and BpAUX2,which might contribute to root growth and root xylem synthesis,and by upregulating BpSOD2 and BpPOD34 to enhance the antioxidant enzyme system.This work provides a new insight into the application of IAA in the remediation of soil Cd pollution by mycorrhizal plants.

关键词： enzyme activity geneexpression heavy metal phytoremediation remediation Rhizophagus irregularis soil cadmium pollution stress tolerance

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Backstepping-based Diving Control design for Underactuated AUVs Combined with ILOS Method

Backstepping-based Diving Control design for Underactuated A...

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第37届中国控制会议

作者： Hui Ye wentao xue Xiaofei Yang School of Electronics and Information Jiangsu University of Science and Technology

This paper presents a precise diving control for underactuated autonomous underwater vehicles（AUVs） in the presence of vertical ocean currents by using backstepping technique.In order to eliminate the effect of ocean currents,integral action is introduced into the line-of-sight（LOS） guidance principle and a new steer law of the guidance is proposed.Then a kinematic and dynamic controller is obtained according to Lyapunov-based method.It can be proved that the closed-loop system is asymptotically stable and the cross-track error of the AUV is gradually converged to zero.Simulations illustrate the effectiveness of the proposed control scheme.

关键词： autonomous underwater vehicle backstepping diving control line-of-sight

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A Moving Target Tracking Control and Obstacle Avoidance of Quadrotor UAV Based on Sliding Mode Control Using Artificial Potential Field and RBF Neural Networks

A Moving Target Tracking Control and Obstacle Avoidance of Q...

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第三十九届中国控制会议

作者： Xuan Chen wentao xue Haiyang Qiu Hui Ye School of Electronics and Information Jiangsu Universtiy of Science and Technology

A new control method for an underactuated quadrotor unmanned aerial vehicle（UAV） is proposed to solve the problem of moving target tracking and obstacle avoidance. In order to achieve a better target tracking and obstacle avoidance control, the dynamic model of quadrotor UAV is decoupled into position control subsystem and attitude control subsystem. Firstly, a method combining artificial potential field（APF） with sliding model control is introduced for the position system to track the moving target at a fixed distance in the case of obstacles and external disturbances. Secondly, a sliding mode control method based on radial basis function（RBF） network is applied to ensure the attitude of the quadrotor converges to the desired values. In addition, the stabilities of the two subsystems are respectively proved based on Lyapunov theory. Finally, the simulation results of moving target tracking verify the superiority and robustness of the proposed control method in the presence of obstacles and external interference.

关键词： Quadrotor Moving target tracking Artificial potential field Radial basis function

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Very long wave infrared quantum dot photodetector up to 18μm

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Light(Science & Applications) 2024年第4期13卷 772-782页

作者： Xiaomeng xue Qun Hao Menglu Chen School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China. Westlake Institute for Optoelectronics FuyangHangzhou 311421China. Physics Department Changchun University of Science and TechnologyChangchun 130022China

Colloidal quantum dots(CQDs)are of interest for optoelectronic devices because of the possibility of high-throughput solution processing and the wide energy gap tunability from ultraviolet to infrared wavelengths.People may question about the upper limit on the CQD wavelength region.To date,although the CQD absorption already reaches terahertz,the practical photodetection wavelength is limited within mid-wave infrared.To figure out challenges on CQD photoresponse in longer wavelength,would reveal the ultimate property on these nanomaterials.What’s more,it motivates interest in bottom-up infrared photodetection with less than 10%cost compared with epitaxial growth semiconductor bulk.In this work,developing a re-growth method and ionic doping modification,we demonstrate photodetection up to 18μm wavelength on HgTe CQD.At liquid nitrogen temperature,the responsivity reaches 0.3 A/W and 0.13 A/W,with specific detectivity 6.6×108 Jones and 2.3×109 Jones for 18μm and 10μm CQD photoconductors,respectively.This work is a step toward answering the general question on the CQD photodetection wavelength limitation.

关键词： quantum wave ultraviolet

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Challenges and opportunities in rare cancer research in China

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Science China(Life Sciences) 2024年第2期67卷 274-285页

作者： Jianxin xue Qunyan Lyu Division of Thoracic Tumor Multimodality Treatment Cancer CenterWest China HospitalSichuan UniversityChengdu 610041China National Natural Science Foundation of China Beijing 100085China

Cancer is one of the major public health challenges in China.Rare cancers collectively account for a considerable proportion of all malignancies.The lack of awareness of rare cancers among healthcare professionals and the general public,the typically complex and delayed diagnosis,and limited access to clinical trials are key challenges.Recent years have witnessed an increase in funding for research related to rare cancers in China.In this review,we provide a comprehensive overview of rare cancers and summarize the status of research on rare cancers in China and overseas,including the trends of funding and publications.We also highlight the challenges and perspectives regarding rare cancers in China.

关键词： rare cancers basic research clinical research preclinical model funding scheme

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Character Sheaves for Classical Graded Lie Algebras

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Acta Mathematica Sinica,English Series 2024年第3期40卷 870-884页

作者： Ting xue School of Mathematics and Statistics University of MelbourneVIC 3010Australia Department of Mathematics and Statistics University of HelsinkiHelsinki 00014Finland

In this note we study character sheaves for graded Lie algebras arising from inner automorphisms of special linear groups and Vinberg’s type Ⅱ classical graded Lie algebras.

关键词： Graded Lie algebras character sheaves Fourier transform nilpotent orbits

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Mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence Technology（防务技术） 2024年第1期31卷 510-522页

作者： Xin xue Chao Zheng Fu-qiang Lai xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this paper.Firstly,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum brazing.Secondly,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried out.The primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so on.The results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner skin.The axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the skin.Moreover,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping

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Effects of microenvironment and biological behavior on the paracrine function of stem cells

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Genes & Diseases 2024年第1期11卷 135-147页

作者： Zhixin xue Yunjun Liao Ye Li The Department of Plastic and Cosmetic Surgery Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China

Mesenchymal stem cells(MSCs),the most well-studied cell type in the field of stem cell therapy,have multi-lineage differentiation and self-renewal potential.MsC-based thera-pies have been used to treat diverse diseases because of their ability to potently repair tissue and locally restore function.An increasing body of evidence demonstrates that paracrine func-tion is central to the effects of MsC-based therapy.Growth factors,cytokines,chemokines,extracellular matrix components,and extracellular vehicles all contribute to the beneficial ef-fects of MSCs on tissue regeneration and repair.The paracrine substances secreted by MSCs change depending on the tissue microenvironment and biological behavior.In this review,we discuss the bioactive substances secreted by MsCs depending on the microenvironment and biological behavior and their regulatory mechanisms,which explain their potential to treat human diseases,to provide new ideas for further research and clinical cell-free therapy.

关键词： Bioactive behavior Mesenchymal stem cells Microenvironment Paracrine Secretome

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