检索结果-南通市图书馆

Complications of microvascular decompression in hemifacial spasm treatment Retrospective analysis of 156 cases

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2008年第1期3卷 101-103页

作者： Yongfeng Sun Guanghui dai jun yuan Weidong Zhai Jianwei Zhong Tao Wang Department of Neurosurgery Beijing General Group Hospital the Chinese People＇s Armed Police Forces Beijing 100027 China

BACKGROUND： Microvascular decompression has become a well-accepted, safe method in the treatment of hemifacial spasms. However, postoperative complications exist and influence the prognosis of the disease. OBJECTIVE： This study aimed to analyze, by case review, the characteristics and regularity of microvascular decompression complications in the treatment of hemifacial spasm. DESIGN： Retrospective analysis. SETTING： Beijing General Group Hospital of the Chinese People＇s Armed Police Forces. PARTICIPANTS： A total of 156 patients with hemifacial spasm were admitted to the Department of Neurosurgery, Beijing General Group Hospital of the Chinese People＇s Armed Police Forces from june 2004 to june 2006 and recruited for this study. The patients, 57 males and 99 females, averaged 46 years of age （range 17-68-years old）. All suffered from facial innervated muscular paroxysmal and recurrent contraction, which could not be controlled by consciousness. Electromyogram demonstrated waves of fibrillation and fasciculation. Prior to admission, all patients had received other treatments. Written informed consents for treatment were obtained from all patients. This protocol was approved by the Hospital＇s Ethics Committee. METHODS： After anesthesia, a cranial bone pore was drilled below the connection of the lateral sinus and sigmoid sinus. Dura mater was dissected at the ＂⊥＂ shape and held in the air. Under microscopy, the flocculus cerebelli was lifted slightly up for convenient observation of the cerebellopontine angle. The mucous membrane was sharply separated. Corresponding vessels were identified at the root of the facial nerves and subsequently liberated and disassociated from the root exit zone. Suitably sized Teflon cotton was placed between the corresponding vessels and brain stem. MAIN OUTCOME MEASURES： Complications of microvascular decompression. RESULTS： All 156 patients participated in the final analysis. （1） Postoperatively, 66 （42%） patients presented with obvious

关键词： microvascular decompression hemifacial spasm postoperative complication

Visible-light photoredox-mediated oxidation of N-methyl tertiaryamines under catalyst free conditions:Direct synthesis of methylene-bridged bis-1,3-dicarbonyl compounds

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2014年第4期25卷 545-548页

作者： Xiao-jun dai Xiao-Liang Xu Dong-Ping Cheng Xiao-Nian Li Institute of Industrial Catalysis College of Chemical Engineering and Materials ScienceZhejiang University of Technology College of Pharmaceutical Science Zhejiang University of Technology

Mediated by visible light-induced photoredox catalysis and free of other catalysts, a new and efficient synthesis of methylene-bridged bis-l,3-dicarbonyl derivatives has been developed. A variety of N-methyl tertiarya... 详细信息

关键词： Photochemistry Oxidation Aliphatic tertiaryamine Catalyst free

在线全文

学校读者我要写书评

暂无评论

激光-电场混合推进技术发展现状

战术导弹技术 2024年第4期 103-114页

作者：段卜仁马腾飞王科伟李彤黄金红徐宁代俊辽宁北方华丰特种化工有限公司抚顺113003 辽宁省宇航级火工品重点实验室抚顺113003 北京理工大学机电学院北京100081 空军装备部驻沈阳地区第四军事代表室沈阳110034 陆军装备部驻抚顺地区军事代表室抚顺113122

激光推进和电推进都具备各自独特的优势,将激光推进和电推进结合,能够实现两种推进技术优势互补、缺点共同消除的目的。针对激光-电场混合推进技术进行了系统介绍,总结了推力器的结构设计、推进剂研制、测试方法等内容。结合综述内容,... 详细信息

激光推进和电推进都具备各自独特的优势,将激光推进和电推进结合,能够实现两种推进技术优势互补、缺点共同消除的目的。针对激光-电场混合推进技术进行了系统介绍,总结了推力器的结构设计、推进剂研制、测试方法等内容。结合综述内容,得到如下结论:激光-电场混合推进技术具有比冲大、体积小等特点,能够为微纳卫星姿态调整提供动力支持;其中,静电场耦合方案的结构简单,但是推力较小,目前仅停留在理论研究阶段,未形成原理样机,工程应用前景有限;电磁场耦合方案的推力性能更为优越,系统集成难度低,未来应致力于减小系统质量和体积,集成激光器、推力器、控制系统等模块,以实现星载推力器的应用。

关键词：激光-电场混合推进技术静电式耦合电磁式耦合推进剂

Effects of Rattling Behavior of K and Cd Atoms along Different Directions in Anisotropic KCdAs on Lattice Thermal Transport and Thermoelectric Properties

在线全文

学校读者我要写书评

暂无评论

Energy & Environmental Materials 2024年第6期7卷 388-398页

作者： Yue Wang Yinchang Zhao jun Ni Zhenhong dai Department of Physics Yantai UniversityYantai 264005China State Key Laboratory of Low-Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China

We employ advanced first principles methodology,merging self-consistent phonon theory and the Boltzmann transport equation,to comprehensively explore the thermal transport and thermoelectric properties of ***,the study accounts for the impact of quartic anharmonicity on phonon group velocities in the pursuit of lattice thermal conductivity and investigates 3ph and 4ph scattering processes on phonon *** various methodologies,including examining atomic vibrational modes and analyzing 3ph and 4ph scattering processes,the article unveils microphysical mechanisms contributing to the lowκL within *** features include significant anisotropy in Cd atoms,pronounced anharmonicity in K atoms,and relative vibrations in non-equivalent As atomic *** atoms,situated between As layers,exhibit rattling modes and strong lattice anharmonicity,contributing to the observed lowκ*** flat bands near the valence band maximum translate into high PF,aligning with ultralowκL for exceptional thermoelectric *** optimal temperature and carrier concentration doping,outstanding ZT values are achieved:4.25(a(b)-axis,p-type,3×10^(19)cm^(−3),500 K),0.90(c-axis,p-type,5×10^(20)cm^(−3),700 K),1.61(a(b)-axis,n-type,2×10^(18)cm^(−3),700 K),and 3.06(c-axis,n-type,9×10^(17)cm^(−3),700 K).

关键词： anharmonic lattice dynamics electron transport characteristics first principles calculation lattice thermal transport octahedron thermoelectric properties

Programmable time-domain digital-coding metasurface for non-linear harmonic manipulation and new wireless communication systems

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

National Science Review 2019年第2期6卷 231-238页

作者： Jie Zhao Xi Yang jun Yan dai Qiang Cheng Xiang Li Ning Hua Qi jun Chen Ke Guo Dong Bai Shuo Liu Shi Jin Andrea Alù Tie jun Cui State Key Laboratory of Millimeter Waves Southeast University Jiangsu Cyber-Space Science & Technology Co. Ltd Physics Program The Graduate Center City University of New York National Mobile Communication Research Laboratory Southeast University Synergetic Innovation Center of Wireless Communication Technology Southeast University Department of Electrical Engineering City College of New York Photonics Initiative Advanced Science Research Center City University of New York

Optical non-linear phenomena are typically observed in natural materials interacting with light at high intensities, and they benefit a diverse range of applications from communication to sensing. However,controlling harmonic conversion with high efficiency and flexibility remains a major issue in modern optical and radio-frequency systems. Here, we introduce a dynamic time-domain digital-coding metasurface that enables efficient manipulation of spectral harmonic distribution. By dynamically modulating the local phase of the surface reflectivity, we achieve accurate control of different harmonics in a highly programmable and dynamic fashion, enabling unusual responses, such as velocity illusion. As a relevant application, we propose and realize a novel architecture for wireless communication systems based on the time-domain digital-coding metasurface, which largely simplifies the architecture of modern communication systems, at the same time yielding excellent performance for real-time signal transmission. The presented work, from new concept to new system, opens new pathways in the application of metamaterials to practical technology.

关键词： metasurface time-domain digital coding non-linear harmonics control new architecture of communication

Combined effects of earthworms and biochar on PAHs-contaminated soil remediation:A review

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Soil Ecology Letters 2023年第2期5卷 3-26页

作者： Shuyu Hou Jue Wang jun dai Mohammed Boussafir Chi Zhang College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China ISTO UMR 7327 CNRS-Universitéd’Orléans Orléans45071France E.A 6293 GéoHydrosytèmes COntinentaux(GeHCO) Facultédes Sciences et TechniquesParc de Grandmont37200 ToursFrance

Polycyclic aromatic hydrocarbons(PAHs)in soil pose a threat to the health of humans and other organisms due to their *** remediation method of combined application of biochar and earthworms has received growing attention owing to its effectiveness in PAHs ***,the earthworm-biochar interaction and its influence on PAHs in soil has not been systematically *** review focuses on the effectiveness of combined application of earthworms and biochar in the remediation of PAHs-contaminated soils and the underlying mechanisms,including adsorption,bioaccumulation,and ***-biochar interaction activates the functional microorganisms in soil and the PAHs-degrading microorganisms in earthworm guts,promoting PAHs *** review provides a theoretical support for the combined application of biochar and earthworms in the remediation of PAHs-contaminated soils,points out the limitations of this remediation method,and finally shows the prospects for future research.

关键词： earthworm biochar soil PAHs combined effect

A uniformly valid series solution to the unsteady stagnation-point flow towards an impulsively stretching surface

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 521-526页

作者： CHENG jun & dai ShiQiang Shanghai Institute of Applied Mathematics and Mechanics, Shanghai University, Shanghai 200072, China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai China

The paper studies the problem of the unsteady two-dimensional stagnation-point flow of an incompressible viscous fluid over a flat deformable sheet. The flow is started impulsively from rest and the sheet is suddenly stretched in its own plane with a velocity proportional to the distance from the stagnation point. An analytical series solution is obtained by means of the homotopy analysis method (HAM). Also, the homotopy-Pade′ technique is employed. An explicit formula for the local friction coefficient is provided. The present formula, different from the perturbation solution, is accurate and uniformly valid for all dimensionless time in the whole spatial region and for all possible values of physical parameter λ, defined as the ratio of the potential flow velocity to the sheet sudden stretching velocity. Numerical tests are done to verify the present formula for its validity and accuracy.

关键词： unsteady boundary-layer flows stagnation point stretching sheet homotopy analysis method

Rubratoxin C,a new nonadride derivative from an endophytic fungus Penicillium sp.F-14

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2014年第9期25卷 1308-1310页

作者： Ri-Dao Chen Zheng Yan Jian-Hua Zou Nan Wang jun-Gui dai State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaPeking Union Medical College & Chinese Academy of Medical Sciences

One new nonadride derivative rubratoxin C （1） together with a known compound rubratoxin B （2） were isolated from an endophytic fungus Penicillium sp. F-14. Their structures were elucidated by various spectroscopic methods. Bioassays showed that 2 had moderate cytotoxic effect against HCT-8, BEL-7402, Ketr3, A2780, MCF-7 and BGC-823 human cancer cell lines, and 1 exhibited weak activity.

关键词： Nonadride derivative Endophytic fungus Natural products Cytotoxic activity

Two new cytotoxic sesquiterpenoids from Solanum lyratum

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2013年第11期24卷 1030-1032页

作者： Gui-Sheng Li Fang Yao Lei Zhang Xi-Dian Yue Sheng-jun dai School of Pharmaceutical Science Yantai University

Two new sesquiterpenoids,attributable to eudesmane-type（1 and 2,named solajiangxins F and G）,were isolated from the whole plant of Solanum *** structures were elucidated on the basis of integrated spectroscopic *** vitro,compounds 1 and 2 were found to show signifcant cytotoxic activity against selected cancer cells,including P-388,HONE-1 and HT-29.

关键词： Solanum lyratum Solanaceae Sesquiterpenoid Solajiangxins F–G Cytotoxic activity