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Rare Metals 2024年第2期43卷 682-691页

作者： Ji Zhou Bin-Bin Liu Hu Zheng Wen-Qing Ma Qian Li cai-Xia xu Institute for Advanced Interdisciplinary Research(iAIR) Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of ShandongSchool of Chemistry and Chemical EngineeringUniversity of JinanJinan250022China

Co_(3)V_(2)O_(8)/Co_(3)O_(4)/Ti_(3)C_(2)T_(x) composite was easily synthesized via one-step succinct-operated hydrothermal process.The interconnected Co_(3)V_(2)O_(8)/Co_(3)O_(4) nanowires network can in-situ grow and anchor on the surface of Ti_(3)C_(2)T_(x) via the strong Co-F bonds and contribute tremendously to depress Ti_(3)C_(2)T_(x) self-restacking.Profiting from the synergistically interplayed effect among the multiple interfaces and high conductivity of Ti_(3)C_(2)T_(x) as well as outstanding stability of the as-designed nanostructure,the optimum Co_(3)V_(2)O_(8)/Co_(3)O_(4)/Ti_(3)C_(2)T_(x)electrode reaches a commendable specific capacitance(up to 3800 mF·cm^(−2)),great rate capability(80%capacitance retention after 20-times current increasing),and preeminent cycling stability(95.4%/85.5%retention at 7000th/20,000th cycle).Moreover,the all-solid-state asymmetric supercapacitor based on Co_(3)V_(2)O_(8)/Co_(3)O_(4)/Ti_(3)C_(2)T_(x) and active carbon can deliver a high energy density of 84.0μWh·cm^(−2) at the power energy of 3.2 mW·cm^(−2),and excellent cycling durability with 87.0%of initial capacitance retention upon 20,000 loops.This work provides a practicable pathway to tailor MXene-based composites for high-performance supercapacitor.

关键词： Ti_(3)C_(2)T_(x) Co_(3)V_(2)O_(8)/Co_(3)O_(4) Heterostructure Cathode Supercapacitor

COVID-19 pandemic amplified mortality rates among adolescents with bipolar disorder through family-related factors

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World Journal of Clinical Cases 2024年第11期12卷 1929-1935页

作者： Zhuo-Fan Ye Yi-Han Hong Jian-Lin Yang Meng-Qing Tan Ju-Min Xie Zu-cai xu Department of Neurology The Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Hubei Key Laboratory of Renal Disease Occurrence and Intervention Medical SchoolHubei Polytechnic UniversityHuangshi 435003Hubei ProvinceChina Psychological Children's Ward Mental Health Center of HuangshiHuangshi 435111Hubei ProvinceChina The Collaborative Innovation Center of Tissue Damage Repair and Regeneration Medicine Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina

BACKGROUND Recently,a growing number of adolescents have been afflicted with mental disorders,with annual morbidity rates on the rise.This trend has been exacerbated by the global coronavirus disease 2019(COVID-19)pandemic,leading to a surge in suicide and self-harm rates among this demographic.AIM To investigate the impact of the COVID-19 pandemic on adolescent bipolar disorder(BD),along with the underlying factors contributing to heightened rates of suicide and self-harm among adolescents.METHODS A comprehensive statistical analysis was conducted utilizing clinical interviews and self-reports obtained from patients or their guardians.Diagnostic criteria for BDs were based on the Diagnostic and statistical manual of mental disorders,international classification of diseases-11,and the National institute of mental health research domain criteria.Statistical analyses were performed using SPSS 26.0 software,with significance set at P<0.05.RESULTS A cohort of 171 adolescents diagnosed with BD between January 1,2018,and December 31,2022,was included in the analysis.The gender distribution was 2.8:1(female to male),with ages ranging from 11 to 18 years old.Major factors contributing to adolescent BDs included familial influences,academic stress,genetic predisposition and exposure to school-related violence.Notably,a significant increase in suicide attempts and self-harm incidents was observed among adolescents with BD during the COVID-19 pandemic.Statistical analysis indicated that the pandemic exacerbated familial discord and heightened academic stress,thereby amplifying the prevalence of suicidal behavior and self-harm among adolescents.CONCLUSION The COVID-19 pandemic has exacerbated familial tensions and intensified the incidence of suicide and self-harm among adolescents diagnosed with BD.This study underscores the urgent need for societal,familial and educational support systems to prioritize the well-being of adolescents and offers valuable insights and guidelines for the prevention,diagnosis and treatment of ad

关键词： Adolescents Bipolar disorder COVID-19 Suicide Self-harm

High-precision X-ray polarimeter based on channel-cut crystals

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Nuclear Science and Techniques 2024年第3期35卷 30-39页

作者： Shang-Yu Si Zhong-Liang Li Wen-Hong Jia Lian xue Hong-Xin Luo Jian-cai xu Bai-Fei Shen Lin-Gang Zhang Liang-Liang Ji Yu-Xin Leng Ren-Zhong Tai Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was measured.This result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet source.Notably,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.

关键词： X-ray polarimeter Vacuum birefringence Synchrotron radiation Channel-cut crystal

Quantum Anomalous Hall Effect with Tunable Chern Numbers in High-Temperature 1T-PrN_(2) Monolayer

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Chinese Physics Letters 2024年第5期41卷 77-84页

作者：吴绪才李树宗司君山黄博张卫兵 Hunan Provincial Key Laboratory of Flexible Electronic Materials Genome Engineering School of Physics and Electronic SciencesChangsha University of Science and TechnologyChangsha 410114China

Quantum anomalous Hall(QAH) insulators have highly potential applications in spintronic device. However,available candidates with tunable Chern numbers and high working temperature are quite rare. Here, we predict a 1T-PrN_(2) monolayer as a stable QAH insulator with high magnetic transition temperature of above 600 K and tunable high Chern numbers of C = ±3 from first-principles calculations. Without spin-orbit coupling(SOC),the 1T-PrN_(2) monolayer is predicted to be a p-state Dirac half metal with high Fermi velocity. Rich topological phases depending on magnetization directions can be found when the SOC is considered. The QAH effect with periodical changes of Chern number(±1) can be produced when the magnetic moment breaks all twofold rotational symmetries in the xy plane. The critical state can be identified as Weyl half semimetals. When the magnetization direction is parallel to the z-axis, the system exhibits high Chern number QAH effect with C = ±3.Our work provides a new material for exploring novel QAH effect and developing high-performance topological devices.

关键词： magnetization topological monolayer

Flow characteristics in a rotor-stator cavity with cooling air inlet at low radius

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航空动力学报 2015年第4期30卷 775-783页

作者： cai xu LUO Xiang ZHAO Xi xuGuo-qiang cai Jun National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China Dalian Airforce Department of Information Network Communicaiton Non-Commissioned Office Academy Dalian Liaoning 116600 China Guizhou Aero-Engine Research Institute Aviation Industry Corporation of China Guiyang 550081 China

Experiments were conducted on a typical rotor-stator system where air entered through an annular slot at low radius and flowed out of the cavity axially through a rim seal between the rotor and the stator.For the seal in this rotor-stator system,the stationary shroud overlapped the rotating one.Pressure distributions at the stator surface and flow resistance coefficients of the rotor-stator cavity with a maximum gap of 67mm were measured under different dimensionless mass flow rates from 1.32×104 to 4.87×104 with a large range of rotational Reynolds numbers from 0.418×106 to 2.484×106.The results show that pressure on the stator surface decreases with the increase of rotational Reynolds number when the dimensionless mass flow rate is below 1.3×104;when the dimensionless mass flow rate is above 3.034×104,the trend reverses.This is the so-called"pressure inversion effect".However,dimensionless pressure does not show the same changes when rotational dynamic pressure is chosen as the denominator.The resistance coefficient of the rotor-stator cavity is determined by the dimensionless mass flow rate and rotational Reynolds number;for practical application,the resistance coefficient can also be estimated by the turbulent flow parameter in the range of turbulent parameter from 0.1to 1.6.

关键词： cooling system rotor-stator system flow characteristics pressure distribution resistance coefficient

Response to roxadustat in a patient undergoing long-term dialysis and allergic to erythropoiesis-stimulating agents:A case report

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World Journal of Clinical Cases 2022年第35期10卷 13122-13128页

作者： cai xu Deng-Gui Luo Zhe-Yan Liu Dong Yang Dan-Dan Wang Yuan-Zhao xu Jun Yang Bo Fu Ai-Rong Qi Department of Nephrology The Fourth Affiliated Hospital of Guangzhou University of Chinese MedicineShenzhen 518000Guangdong ProvinceChina Department of Nephrology Shenzhen Traditional Chinese Medicine HospitalShenzhen 518000Guangdong ProvinceChina

BACKGROUND Hypoxia-inducible factor prolyl hydroxylase inhibitor is a new class of drugs for treating renal anemia.It is a second-generation hypoxia-inducible factor prolyl hydroxylase-2(PHD2)inhibitor.Roxadustat can effectively increase hemoglobin in patients with dialysis-dependent chronic kidney disease,with an adverse events profile comparable to that of epoetin alfa.We administered roxadustat to a maintenance hemodialysis patient who was allergic to erythropoiesis-stimulating agents(ESAs)and depended on blood transfusion for five years.After applying Roxadustat,the patient’s anemia improved significantly.CASE SUMMARY A 77-year-old Chinese man had type 2 diabetes for 16 years,underwent maintenance hemodialysis for five years,and had fatigue for five years.Laboratory tests showed severe anemia(hemoglobin concentration of 42 g/L).The patient was administered a subcutaneous injection of ESAs before dialysis.He suffered an allergic shock immediately and fainted.His blood pressure dropped to undetectable levels.He was not administered ESAs henceforth.The patient was prescribed iron supplements and received blood transfusions occasionally for five years.His hemoglobin concentration ranged from 42-68 g/L.After taking six weeks of oral roxadustat three times weekly(100 mg TIW),the patient’s hemoglobin concentration increased significantly,and his symptoms decreased.We adjusted the doses of roxadustat,and the hemoglobin concentration was maintained between 97 and 126 g/L.CONCLUSION Oral roxadustat is effective in treating anemia in maintenance hemodialysis patients who cannot be administered ESAs.

关键词： Chronic kidney disease Hemodialysis Anemia Roxadustat Erythropoiesis-stimulating agents Allergic shock Case report

基于数据-模型融合驱动的新能源场站宽频阻抗在线辨识及稳定性评估

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中国电机工程学报 2024年第7期44卷 2670-2684,I0013页

作者：饶仪明吕敬王众蔡旭电力传输与功率变换控制教育部重点实验室(上海交通大学) 上海市闵行区200240

风电、光伏等新能源在电网中的渗透率不断提高,导致一系列宽频振荡问题。阻抗法是研究新能源并网系统宽频振荡稳定性的有效方法之一,然而由于商业化新能源机组的“黑/灰箱”问题、新能源场站运行状态的随机不确定性等因素,导致新能源场... 详细信息

风电、光伏等新能源在电网中的渗透率不断提高,导致一系列宽频振荡问题。阻抗法是研究新能源并网系统宽频振荡稳定性的有效方法之一,然而由于商业化新能源机组的“黑/灰箱”问题、新能源场站运行状态的随机不确定性等因素,导致新能源场站的精确阻抗/导纳建模困难。为此,提出基于数据-模型融合驱动的新能源场站宽频阻抗/导纳在线辨识方法,针对输入随机不确定的新能源机组,采用数据驱动方法建立其覆盖整个稳态运行工况的宽频阻抗/导纳辨识模型,然后结合新能源场站的物理结构模型,构建数据-模型融合驱动的新能源场站宽频阻抗/导纳在线辨识模型。最后,以风电并网系统为例,利用建立的导纳辨识模型对风电并网系统的宽频振荡稳定性进行在线评估,并通过时域仿真验证稳定性在线分析的正确性。

关键词：数据驱动风电场神经网络阻抗导纳稳定性在线评估

基于二极管分散整流的风电机组中压直流汇集直接送出系统

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电力系统自动化 2024年第2期48卷 9-19页

作者：杨明扬王晗蔡旭张建文上海交通大学电子信息与电气工程学院上海市200240

基于二极管分散整流的风电机组中压直流汇集直接送出系统可以省去海上升压站及海上换流站,对于中远距离、中等规模海上风电具有突出经济优势。针对其特有的输电电流纹波问题,建立了多机动态移相参考坐标系(DPSRF)并提出按DPSRF坐标系d... 详细信息

基于二极管分散整流的风电机组中压直流汇集直接送出系统可以省去海上升压站及海上换流站,对于中远距离、中等规模海上风电具有突出经济优势。针对其特有的输电电流纹波问题,建立了多机动态移相参考坐标系(DPSRF)并提出按DPSRF坐标系d轴定向的电压矢量控制,实现多台机组的分散式二极管整流器整流电流矢量和输出电流纹波的交错分布,有效降低直流输电电流和电压纹波。计及纹波交错算法中动态移相角影响,建立风电机组网侧变换器小信号状态空间模型,基于特征根分析辨识系统弱阻尼环节,并针对性地提出镇定控制策略。发挥该系统有望免除直流断路器的优势,制定了基于扰动注入的故障定位策略,配合继电保护逻辑和机组动作时序实现无通信依赖的直流内网多故障位置故障定位与隔离。最后,PSCAD仿真和基于RT-LAB的硬件在环实验验证了所提控制保护策略的有效性。

关键词：海上风电直流汇集直流输电控制与保护

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基于先验地图的视觉重定位方法综述

软件学报 2024年第2期35卷 975-1009页

作者：蔡旭东王永才白雪薇李德英中国人民大学信息学院北京100872

在自动驾驶、增强现实和智能移动机器人领域,视觉重定位是非常重要的基础问题.视觉重定位是指根据视觉传感器实时拍摄的数据,在已有先验地图中确定位置和姿态的问题.过去数十年间,该问题受到广泛关注,涌现出种类繁多的先验地图构建方法... 详细信息

在自动驾驶、增强现实和智能移动机器人领域,视觉重定位是非常重要的基础问题.视觉重定位是指根据视觉传感器实时拍摄的数据,在已有先验地图中确定位置和姿态的问题.过去数十年间,该问题受到广泛关注,涌现出种类繁多的先验地图构建方法和视觉重定位方法.这些工作差异大,涉及范围广,技术概括和总结尚缺乏.因此,对视觉重定位领域进行综述具有重要的理论和应用价值.尝试为视觉重定位相关方法建立一个统一的蓝图,从图像数据在大规模地图数据库中查询的角度对相关工作进行分析和总结.综述不同类型地图数据库构建方法、不同特征匹配、重定位和位姿计算方法,总结目前视觉重定位的主流数据集,最后分析视觉重定位存在的挑战和潜在发展方向.

关键词：先验地图地图构建位姿估计视觉重定位

Optimal foldover plans of three-level designs with minimum wrap-around L-_2 discrepancy

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Science China Mathematics 2015年第7期58卷 1537-1548页

作者： OU ZuJun QIN Hong cai xu College of Mathematics and Statistics Jishou University School of Physical Science and Technology Central China Normal University School of Mathematics and Statistics Central China Normal University

Abstract The objective of this paper is to study the issue of employing the uniformity criterion measured by the wrap-around L2-discrepancy to assess the optimal foldover plans for three-level designs.For three-level fractional factorials as the original designs,the general foldover plan and combined design under a foldover plan are defined,some theoretical properties of the defined foldover plans are obtained,a tight lower bound of the wrap-around L2-discrepancy of combined designs under a general foldover plan is also obtained,which can be used as a benchmark for searching optimal foldover plans.For illustration of the usage of our theoretical results,a catalog of optimal foldover plans for uniform initial designs with s three-level factors is tabulated,where 2≤ s ≤11.

关键词：级设计环绕初始设计均匀性三电平目录表定义搜索