检索结果-南通市图书馆

Frontiers of physics 2024年第3期19卷 51-59页

作者： Qingwang Bai mingxiang Xu School of Physics Southeast UniversityNanjing 211189China

As an intrinsic magnetic topological insulator with magnetic order and non-trivial topological structure,MnBi_(2)Te_(4)is an ideal material for studying exotic topological states such as quantum anomalous Hall effect and topological axion insulating ***,we carry out magnetic and electrical transport measurements on(Mn1–xGex)Bi_(2)Te_(4)(x=0,0.15,0.30,0.45,0.60,and 0.75)single *** is found that with increasing x,the dilution of magnetic moments gradually weakens the antiferromagnetic exchange ***,Ge doping reduces the critical field of ferromagnetic ordering,which may provide a possible way to implement the quantum anomalous Hall effect at lower magnetic *** transport measurements suggest that electrons are the dominant charge carriers,and the carrier density increases with the Ge doping ***,the Kondo effect is observed in the samples with x=0.45,0.60,and *** results suggest that doping germanium is a viable way to tune the magnetic and electrical transport properties of MnBi_(2)Te_(4),opening up the possibility of future applications in magnetic topological insulators.

关键词： MnBi_(2)Te_(4) intrinsic magnetic topological insulator transition points Kondo effect

design and simulation investigations on charge transport layers‑free in lead‑free three absorber layer all‑perovskite solar cells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Optoelectronics 2024年第2期17卷 69-85页

作者： Guangd.ng Li mingxiang Xu Zhong Chen School of Physics Southeast UniversityNanjing 211189China

The multiple absorber layer perovskite solar cells(PSCs)with charge transport layers-free(CTLs-free)have drawn widespread research interest due to their simplified architecture and promising photoelectric *** the circumstances,the novel design of CTLs-free inversion PSCs with stable and nontoxic three absorber layers(triple Cs_(3)Bi_(2)I_(9),single MASnI_(3),double Cs_(2)TiBr_(6))as optical-harvester has been numerically simulated by utilizing wxAMPS simulation software and achieved high power conversion efficiency(PCE)of 14.8834%.This is owing to the innovative architecture of PSCs favors efficient transport and extraction of more holes and the slender band gap MASnI_(3)extends the absorption spectrum to the near-infrared periphery compared with the two absorber layers architecture of ***,the performance of the device with p-type-Cs_(3)Bi_(2)I_(9)/p-type-MASnI_(3)/n-type-Cs_(2)TiBr_(6)architecture is superior to the one with the p-type-Cs_(3)Bi_(2)I_(9)/ntype-MASnI_(3)/n-type-Cs_(2)TiBr_(6)architecture due to less carrier recombination and higher carrier life time inside the absorber *** simulation results reveal that Cs_(2)TiF_(6)double perovskite material stands out as the best ***,an excellent PCE of 21.4530%can be obtained with the thicker MASnI_(3)absorber layer thickness(0.4μm).Lastly,the highestperformance photovoltaic devices(28.6193%)can be created with the optimized perovskite doping density of around E15 cm^(3)(Cs_(3)Bi_(2)I_(9)),E18 cm^(3)(MASnI_(3)),and 1.5E19 cm^(3)(Cs_(2)TiBr_(6)).This work manifests that the proposed CTLs-free PSCs with multi-absorber layers shall be a relevant reference for forward applications in electro-optical and optoelectronic devices.

关键词： Multiple absorber layer PSCs CTLS-free·Inverted Narrow-band gap Simulation

Feedback linearization and equivalent-disturbance compensation control strategy for piezoelectric stage

在线全文

学校读者我要写书评

暂无评论

Nanotechnology and Precision Engineering 2024年第2期7卷 49-59页

作者： Tao Huang Yingbin Wang Zhihong Luo Huajun Cao Guibao Tao mingxiang Ling State Key Laboratory of Mechanical Transmissions for Advanced Equipment Chongqing UniversityChongqing 400044China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China Hongdu Aviation Industry Group NanchangJiangxi 330000China Robotics and Microsystems Center Soochow UniversitySuzhou 215123China

Piezoelectric stages use piezoelectric actuators and flexure hinges as driving and amplifying mechanisms,*** systems have high positioning accuracy and high-frequency responses,and they are widely used in various precision/ultra-precision positioning ***,the main challenge with these devices is the inherent hysteresis nonlinearity of piezoelectric actuators,which seriously affects the tracking accuracy of a piezoelectric *** by this challenge,in this work,we developed a Hammerstein model to describe the hysteresis nonlinearity of a piezoelectric *** particular,in our proposed scheme,a feedback-linearization algorithm is used to eliminate the static hysteresis *** addition,a composite controller based on equivalent-disturbance compensation was designed to counteract model uncertainties and external *** analysis of the stability of a closed-loop system based on this feedback-linearization algorithm and composite controller was performed,and this was followed by extensive comparative experiments using a piezoelectric stage developed in the *** experimental results confirmed that the feedback-linearization algorithm and the composite controller offer improved linearization and trajectory-tracking performance.

关键词： Piezoelectric stage Hysteresis nonlinearity Feedback linearization Equivalent-disturbance compensation

Tumor necrosis factor-stimulated gene-6 ameliorates early brain injury after subarachnoid hemorrhage by suppressing NLRC4 inflammasome-mediated astrocyte pyroptosis

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第5期19卷 1064-1071页

作者： mingxiang d.ng Lei Jin Boyang Wei Wenping Cheng Wenchao Liu Xifeng Li Chuanzhi duan Neurosurgery Center Department of Cerebrovascular SurgeryThe National Key Clinical SpecialtyThe Engineering Technology Research Center of Education Ministry of China on Diagnosis and Treatment of Cerebrovascular DiseaseGuangdong Provincial Key Laboratory on Brain Function Repair and RegenerationThe Neurosurgery Institute of Guangdong ProvinceZhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina department of Cerebrovascular Intervention Zhongshan City People’s HospitalZhongshanGuangdong ProvinceChina

Subarachnoid hemorrhage is associated with high morbidity and mortality and lacks effective *** is a crucial mechanism underlying early brain injury after subarachnoid *** studies have confirmed that tumor necrosis factor-stimulated gene-6(TSG-6)can exert a neuroprotective effect by suppressing oxidative stress and ***,no study to date has explored whether TSG-6 can alleviate pyroptosis in early brain injury after subarachnoid *** this study,a C57BL/6J mouse model of subarachnoid hemorrhage was established using the endovascular perforation *** results indicated that TSG-6 expression was predominantly detected in astrocytes,along with NLRC4 and gasdermin-d(GSdMd).The expression of NLRC4,GSdMd and its N-terminal domain(GSdMd-N),and cleaved caspase-1 was significantly enhanced after subarachnoid hemorrhage and accompanied by brain edema and neurological *** explore how TSG-6 affects pyroptosis during early brain injury after subarachnoid hemorrhage,recombinant human TSG-6 or a siRNA targeting TSG-6 was injected into the cerebral *** TSG-6 administration downregulated the expression of NLRC4 and pyroptosis-associated proteins and alleviated brain edema and neurological ***,TSG-6 knockdown further increased the expression of NLRC4,which was accompanied by more severe astrocyte *** summary,our study revealed that TSG-6 provides neuroprotection against early brain injury after subarachnoid hemorrhage by suppressing NLRC4 inflammasome activation-induced astrocyte pyroptosis.

关键词： astrocyte early brain injury inflammasome NLRC4 pyroptosis subarachnoid hemorrhage tumor necrosis factor-stimulated gene-6(TSG-6)

基于地理实践力培养的乡土地理实践活动设计与实施--以乡土地理实践活动“‘圆梦运盐河’之生态环境保护”教学为例

在线全文

学校读者我要写书评

暂无评论

教师教育论坛 2024年第2期37卷 66-68页

作者：单明祥通州区实验中学江苏南通226300

地理实践力是地理学科核心素养的重要组成部分,包括地理实践知识、地理实践能力和地理实践品格三方面内容。乡土地理教学具有极强的地方性、综合性、实践性等特点,开展乡土地理实践活动有助于更好地发挥地理学科的育人功能,培养学生的... 详细信息

地理实践力是地理学科核心素养的重要组成部分,包括地理实践知识、地理实践能力和地理实践品格三方面内容。乡土地理教学具有极强的地方性、综合性、实践性等特点,开展乡土地理实践活动有助于更好地发挥地理学科的育人功能,培养学生的地理实践力。以乡土地理实践活动“‘圆梦运盐河’之生态环境保护”教学为例,在教学设计中,教师需要进行地理实践活动可行性论证、地理实践活动目标设定和地理实践活动过程设计。在活动实施中,教师需要聚焦活动目标,提高活动质量,组织实践探究,实现学以致用,拓展延伸内容,促进全面发展。

关键词：地理实践力乡土地理实践活动核心素养教学设计

夏季欧亚中高纬大气ISO与欧洲阻塞频率的联系及其对极端高温事件的协同作用

在线全文

学校读者我要写书评

暂无评论

大气科学 2024年第3期48卷 1043-1058页

作者：温昕晟杨双艳高铭祥李天明南京信息工程大学气象灾害教育部重点实验室/气象灾害预报预警与评估协同创新中心/气候与环境变化国际合作联合实验室南京210044 广州市气象台广州511430 夏威夷大学马诺阿分校大气科学学院国际太平洋研究中心美国夏威夷968226 宁夏气象台银川750002

本文利用1979~2018年NCEP逐日再分析资料,探讨了夏季欧亚中高纬地区10~30天大气季节内振荡(ISO)的时空演变及其对欧洲阻塞频率的影响,并探讨了两者对欧亚极端高温发生频率的协同作用。研究表明,欧亚中高纬10~30天大气ISO表现出东传和西... 详细信息

本文利用1979~2018年NCEP逐日再分析资料,探讨了夏季欧亚中高纬地区10~30天大气季节内振荡(ISO)的时空演变及其对欧洲阻塞频率的影响,并探讨了两者对欧亚极端高温发生频率的协同作用。研究表明,欧亚中高纬10~30天大气ISO表现出东传和西传两种模态。东(西)传模态下,对流层西北—东南向倾斜的四极型(东西向分布的偶极型)准正压位势高度异常耦合温度异常同时向东南方向(向西)传播。位相合成表明,在两个模态下,中高纬低频Rossby波列在传播过程中能够显著影响欧洲阻塞的发生。东(西)传模态位相6~7(5~6)期间,欧洲阻塞发生最频繁。在东(西)传模态位相6~7(5~6)期间,欧洲西部、东欧平原、乌拉尔山以及我国东北平原(欧洲和乌拉尔山)地区分别受准正压的+-+-(+-)高度异常控制。有阻塞发生时,东传模态下,欧洲西部的正高度异常强度明显增强,乌拉尔山地区,东欧平原以及我国东北平原地区的高度异常强度均有所减弱。同时,欧洲以南出现负的高度异常;西传模态下,偶极型高度异常强度均增强,欧洲以南和我国东北平原分别出现负的和正的高度异常。可见,在两个模态阻塞频发位相下,阻塞的发生增加了欧洲和我国东北地区极端高温事件的发生频率,降低了欧洲以南和乌拉尔山地区极端高温事件的发生频率。因此,欧洲阻塞活动显著调控了欧亚中高纬地区大气ISO两个传播模态对极端高温事件的影响。

关键词：欧亚中高纬季节内振荡欧洲阻塞极端高温

维普期刊数据库博看期刊

甘草次酸修饰的姜黄素阳离子脂质体肝靶向性和抗肝癌作用研究

在线全文

学校读者我要写书评

暂无评论

药物评价研究 2024年第4期47卷 754-764页

作者：刘炎清李瀚旻常明向陈诺湖北中医药大学中药资源与中药化学重点实验室湖北武汉430065 湖北中医药大学附属湖北省中医院湖北武汉430061

目的研究甘草次酸修饰的姜黄素阳离子脂质体(GAMCLCL)肝靶向性以及抗肝癌作用。方法制备甘草次酸(GA)配体——GA和十八胺盐(SGO),用红外光谱和质谱检测;并进一步利用SGO制备GAMCLCL,透射电镜观察脂质体形态,Nano ZS90纳米粒度仪测定脂... 详细信息

目的研究甘草次酸修饰的姜黄素阳离子脂质体(GAMCLCL)肝靶向性以及抗肝癌作用。方法制备甘草次酸(GA)配体——GA和十八胺盐(SGO),用红外光谱和质谱检测;并进一步利用SGO制备GAMCLCL,透射电镜观察脂质体形态,Nano ZS90纳米粒度仪测定脂质体粒径与电位;采用活体成像系统观察GAMCLCL小鼠体内荧光分布。Wistar大鼠随机分为对照组、模型组、阿霉素(阳性药,2 mg·kg^(−1))组、姜黄素(20 mg·kg^(−1))组和GAMCLCL低、高剂量(2、4 mg·kg^(−1))组,除对照组外,采用Walker-256细胞种植法制备肝原位移植瘤模型,每天1次,尾iv给药,连续7 d;另设GAMCLCL(4 mg·kg^(−1))给药14 d组;称肿瘤质量,计算肝脏系数、脾脏系数;全自动生化分析仪测定血液红细胞(RBC)、白细胞(WBC)、血小板(PLT)、丙氨酸氨基转移酶(ALT)和肌酐(CRE)水平,试剂盒法检测乳酸脱氢酶(LdH)水平;ELISA法检测血清肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)水平;Western blotting法检测肿瘤组织血管内皮生长因子(VEGF)、cleaved Caspase-3、Bcl-2、p53、p-PI3K、p-Akt蛋白表达水平。结果红外光谱和质谱的结果可以验证GA与十八胺的反应生成了SGO;GAMCLCL外观呈球形,其粒径为(194±0.25)nm,聚合物分散性指数(PdI)为0.21±0.02,电位为(31.9±0.31)mV;GAMCLCL在2个月内呈黄色透明溶液,无沉淀析出;GAMCLCL与血清混合未出现任何聚集和沉淀现象;活体成像实验显示,给药后各时间点荧光主要集中在肝脏,10、30、60 min时肝脏荧光较强,120 min时肝脏荧光明显减弱,240 min时肝脏荧光基本消失。与模型组比较,各给药组大鼠肿瘤质量均明显减轻(Pd)组脾脏系数显著下降(Pd)组的RBC和PLT计数均显著升高(PdH显著降低(Pd Caspase-3和P53蛋白表达均显著上调(Pd与14 d的抗肿瘤效果相似,明显强于游离姜黄素。结论GAMCLCL能显著增强姜黄素的肝靶向性和抗肝癌作用,有利于提高荷瘤大鼠的无进展生存期。

关键词：姜黄素甘草次酸阳离子脂质体 Walker 256肝原位移植瘤抗肿瘤作用

在线全文

学校读者我要写书评

暂无评论

三维电镀陶瓷基板激光封焊技术

发光学报 2024年第3期45卷 506-515页

作者：罗霖丁勇杰苏鹏飞赵九洲彭洋陈明祥华中科技大学机械科学与工程学院湖北武汉430074 华中科技大学航空航天学院湖北武汉430074

气密封装是推动电子器件高可靠发展的一项重要技术,传统气密封装技术存在焊接温度高、热冲击大、应用范围窄等问题,无法满足三维电镀陶瓷基板气密封装要求。本文结合脉冲激光焊接的技术优势,研究了脉冲激光焊接三维电镀陶瓷基板实现气... 详细信息

气密封装是推动电子器件高可靠发展的一项重要技术,传统气密封装技术存在焊接温度高、热冲击大、应用范围窄等问题,无法满足三维电镀陶瓷基板气密封装要求。本文结合脉冲激光焊接的技术优势,研究了脉冲激光焊接三维电镀陶瓷基板实现气密封装,重点探讨了焊接过程中脉冲激光与材料相互作用模式,分析了焊接样品界面微观形貌、气密性、力学性能等。研究表明,焊接金属区裂纹的出现与基底金属铜向可伐侧的扩散密切相关;焊接过程稳定、焊接熔深小的热传导模式和过渡模式可以避免焊接裂纹出现。通过试验优化了焊接工艺参数,当激光峰值功率为120 W、脉冲宽度为1 ms、重叠率为80%时,三维陶瓷基板腔体结构获得了最佳高气密性,泄漏率为5.2×10^(-10)Pa·m^(3)/s,接头剪切强度为278.06 MPa,满足第三代半导体器件高可靠气密封装需求。

关键词：脉冲激光焊接模式气密封装三维电镀铜陶瓷基板(3-d dPC)

MULTI-OBJECTIVE OPTIMIZATION IN SPILLWAY PROFILE OF GRAVITY dAM

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 1992年第4期4卷 109-118页

作者： Wang, Shuyu Peng, mingxiang Zhejiang Univ Zhejiang China

Optimal design of overflow surface shape of spillway has been studied in this paper. There are two parts: one is a synchronous iterative method to solve a variational problem with variable domain and unknown discharge for 2-d ideal potential flow; the other concerns and approach to multi-objective optimal design of overflow surface shape. The primary application is successful and satisfactory.

关键词： Gravity dams Numerical methods Optimization Potential flow

在线全文

学校读者我要写书评

暂无评论

儿童原发性右心室滑膜肉瘤1例

中华小儿外科杂志 2024年第1期45卷 71-74页

作者：张明翔郑景浩罗忠明尤国宙洪伟昆明市儿童医院昆明医科大学附属儿童医院心胸外科昆明650100 上海交通大学医学院附属上海儿童医学中心心胸外科上海200127

男,13岁2个月,因"活动后胸闷7 d"就诊于昆明市儿童医院,平日不能耐受长跑。入院查体:心率50次/min,呼吸20次/min,血压120/79 mmHg(1 mmHg=0.133 kPa),体重48.5 kg;一般情况可,口周无发绀,头颈部未触及肿块,心前区可闻及收缩期杂音,心界... 详细信息

男,13岁2个月,因"活动后胸闷7 d"就诊于昆明市儿童医院,平日不能耐受长跑。入院查体:心率50次/min,呼吸20次/min,血压120/79 mmHg(1 mmHg=0.133 kPa),体重48.5 kg;一般情况可,口周无发绀,头颈部未触及肿块,心前区可闻及收缩期杂音,心界无扩大。双肺呼吸音清,腹平软,无压痛,胸腹部未触及包块,四肢活动正常。经胸超声心动图提示右心室内,三尖瓣前叶、隔叶交界处有50 mm×43 mm×29 mm不均匀团块样回声(图1A),致右室流出道中度梗阻.

关键词：右室流出道收缩期杂音双肺呼吸音清滑膜肉瘤昆明市儿童医院经胸超声心动图儿童原发性右心室