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Analysis of the electrical characteristics of GaInP/GaAs HBTs including the recombination effect

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Journal of Semiconductors 2012年第5期33卷 38-43页

作者： Gourab Dutta Sukla Basu Indian Institute of Technology Kharagpur ECE Department Kalyani Government Engineering College

An analytical model is used to predict the effects of surface recombination current on the gain and transit time of GalnP/GaAs heterojunction bipolar transistors（HBTs）.The present analysis shows that consideration of the recombination current gives current gain values that are comparable to those of the experimental *** dependence of current gain on temperature,base doping and emitter area are also analyzed,and the variation in collector current with emitter-base voltage,temperature and doping is considered.

关键词： GaInP/GaAs HBT current gain transit time recombination current surface recombination ideality factor

Combinatorial therapies for spinal cord injury: strategies to induce regeneration

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Neural Regeneration Research 2019年第1期14卷 69-71页

作者： Eduardo D.Gomes Nuno A.Silva António J. Salgado Life and Health Sciences Research Institute (ICVS) School of Medicine University of Minho Campus de Gualtar ICVS/3B’s–PT government Associate Laboratory

Spinal cord injury(SCI)is a condition without treatment,mainly characterized by the loss of motor and sensory function below the level of *** is accompanied by several complications such as cardiac and respiratory compromise,and often patients present psychological ailments associated with the drastic alteration of their normal *** pathophysiology derives from a massive damage to the spinal cord tissue,which is propagated

关键词：损害绳索新生治疗感觉功能生活方式星形细胞并发症

Vibrations of FGM thin cylindrical shells with exponential volume fraction law

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Applied Mathematics and Mechanics(English Edition) 2009年第5期30卷 607-615页

作者： Abdul Ghafar Shah Tahir Mahmood Muhammad Nawaz Naeem Department of Mathematics The Islamia University of Bahawalpur Department of Mathematics Government College University

In this paper, the influence of an exponential volume fraction law on the vibration frequencies of thin functionally graded cylindrical shells is studied. Material properties in the shell thickness direction are graded in accordance with the exponential law. Expressions for the strain-displacement and curvature-displacement relationships are taken from Love＇s thin shell theory. The Rayleigh-Ritz approach is used to derive the shell eigenfrequency equation. Axial modal dependence is assumed in the characteristic beam functions. Natural frequencies of the shells are observed to be dependent on the constituent volume fractions. The results are compared with those available in the literature for the validity of the present methodology.

关键词： functionally graded material (FGM) vibration cylindrical shell Rayleigh- Ritz method exponential volume fraction law

Sedimentation model and analysis for differential settling of two-particle-size suspensions in the Stokes region

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International Journal of Sediment Research 2010年第2期25卷 119-133页

作者： P. KRISHNAMOORTHY Department of Chemistry.Arignar Anna government Arts College

A model is developed for predicting the settling velocity in suspensions of particles of two different sizes based on experimental data for the settling rate of two-size suspensions in various liquids using particles of equal density. In these experiments, the retarding effect of the smaller particles on the settling velocities of the larger ones is taken into account. The model considers Steinour’s fundamental equation and assumes a fixed arrangement of particles and constant velocity in a single-size suspension under creeping flow conditions and the flow spaces changing in shape and size with the volumetric concentration of solids. Based on the foregoing, a simplified model equation is proposed for the settling of particles in a suspension as a function of their free fall velocity and of the solids concentration. Different experimental conditions are used to show the effect of solids concentration, liquid density, and viscosity on the settling behaviour of the glass beads with low particle Reynolds numbers and bed porosity ranging from 0.62 to 0.95. The present study involves the lower and upper interface velocities of two-size suspensions of solids in liquids (concentrated and dilute suspensions) covering a wide range in the properties of the liquids and solids, and more specifically in solids concentration (Glass beads and Sand).

关键词： Settling velocity Suspended sediment Fluid properties Solid concentration

Structural Change in China's Emergency Management: Theoretical Generalizations

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Social Sciences in China 2016年第2期37卷 77-98页

作者：张海波童星 Liu Hao school of government Nanjing University

From the perspective of systems thinking, China＇s emergency management structure can be analyzed in terms of five dimensions： social change, governance transformation, government framework, policy system and operational mechanisms. On the basis of comparative analysis, we discuss structural change across these dimensions by targeting our research on major disasters in the decade from SARS in 2003 to the Lushan earthquake in 2013. Overall, consolidation and evolution coexist in China＇s emergency management structure. At present, structural consolidation has the upper hand, but there are also forces driving structural evolution. Using inductive logic and the comparative method, we arrive at a theoretical generalization about the structural consolidation of China＇s emergency management, demonstrating its ＂comet-shaped＂ structure and ＂comet-tair＇ effect. On this basis, we put forward our theoretical propositions. We believe that the underlying reason for the developmental predicament facing emergency management in China today is that it goes ahead on its own, divorced from structure. Its further development must go back to structure and change with the times, with a view to promoting the structural evolution of China＇s emergency management.

关键词： emergency management systems thinking public governance disaster reliefmechanism policy system social risk

Multi-indicator Evaluation and Analysis of Coordinated Industrial Development of Urban Agglomerations

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Chinese Journal of Urban and Environmental Studies 2017年第1期5卷 98-111页

作者： SUN Xuan Zhou Enlai school of government Nankai University

The level of coordinated industrial development in a region is considered as an important factor of measuring the construction of urban agglomerations. As the economic development patterns and stages vary in regions, a single-standard evaluation system is generally insufficient in evaluating and analyzing the coordinated industrial development of urban agglomerations. This paper, with multivariate values and diversified development demands considered, quantitatively describes the industrial development of urban agglomerations from four dimensions: economics, specialization, balance, and friendliness. On this basis, it synthesizes the indicator parameters effectively and proposes a multi-indicator evaluation model. Through the model, the paper comparatively analyzes the present status and development course of coordinated industrial development of typical urban agglomerations(Beijing–Tianjin–Hebei urban agglomeration, the Yangtze River Delta urban agglomeration, and the Pearl River Delta urban agglomeration) in China. The results show that Beijing–Tianjin–Hebei urban agglomeration has the clearest division of industries, but its industrial spillover effect is limited, the industrial structure of small and medium cities is too simple, and the economic gap among cities narrows at a very slow rate. The core cities in the Yangtze River Delta urban agglomeration exert certain driving effect upon the economy of their surrounding areas. However, they hardly give full play to their comparative advantages due to a low level of regional integration and high industrial similarity among cities. Compared with the above two urban agglomerations, the Pearl River Delta urban agglomeration enjoys more reasonable division of industries among cities, significant driving effect of core cities, and higher level of coordinated industrial development as driven by the market economy.

关键词： Urban agglomeration coordinated industrial development multi-indicator evaluation

Trend of Developing Aqueous Liquid and Gel Electrolytes for Sustainable,Safe,and High‑Performance Li‑Ion Batteries

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Nano-Micro Letters 2024年第1期16卷 17-34页

作者： Donghwan Ji Jaeyun Kim school of Chemical Engineering Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea Department of Health Sciences and Technology Samsung Advanced Institute for Health Sciences&Technology(SAIHST)Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea Biomedical Institute for Convergence at SKKU(BICS) Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea Institute of Quantum Biophysics(IQB) Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea present address:Department of NanoEngineering University of California San DiegoLa JollaSan DiegoCA 92093USA

Current lithium-ion batteries(LIBs)rely on organic liquid electrolytes that pose significant risks due to their flammability and *** potential for environmental pollution and explosions resulting from battery damage or fracture is a critical ***-based(aqueous)electrolytes have been receiving attention as an alternative to organic ***,a narrow electrochemicalstability window,water decomposition,and the consequent low battery operating voltage and energy density hinder the practical use of aqueous ***,developing novel aqueous electrolytes for sustainable,safe,high-performance LIBs remains *** Review first commences by summarizing the roles and requirements of electrolytes–separators and then delineates the progression of aqueous electrolytes for LIBs,encompassing aqueous liquid and gel electrolyte development trends along with detailed principles of the *** aqueous electrolytes are progressed based on strategies using superconcentrated salts,concentrated diluents,polymer additives,polymer networks,and artificial passivation layers,which are used for suppressing water decomposition and widening the electrochemical stability window of water of the *** addition,this Review discusses potential strategies for the implementation of aqueous Li-metal batteries with improved electrolyte–electrode interfaces.A comprehensive understanding of each strategy in the aqueous system will assist in the design of an aqueous electrolyte and the development of sustainable and safe high-performance batteries.

关键词： Lithium-ion battery(LIB) Aqueous electrolyte Gel electrolyte Electrochemical stability window Li dendrite

Incidence and risk factors for vitreous loss in residents performing manual small-incision cataract surgery

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International Journal of Ophthalmology(English edition) 2022年第7期15卷 1071-1076页

作者： Rajesh Subhash Joshi Ashok Hukumchand Madan Preeti Dashrath Wadekar Nivedita Patil Sonali Tamboli Tanmay Surwade Namrata Bansode Department of Ophthalmology Government Medical CollegeNagpur-440003MaharashtraIndia

AIM: To assess the incidence of vitreous loss and associated risk factors in residents performing manual small-incision cataract surgery(MSICS). METHODS: The present retrospective record review study was performed on 490 patients who underwent MSICS performed between November 2018 and December 2019 by 7 third-year postgraduate residents. The study group comprised of patients having intraoperative vitreous prolapse. All the surgeries were performed under supervision of a trained assistant. RESULTS: The mean age of the participants at the time of surgery was 68.42±2.05 y. Of the 490 patients, 250 patients were male, and 240 patients were female(P=0.23). A total of 215(43.9%) eyes had mature white cataract, 185(37.8%) eyes had brown cataract, and 90(18.3%) eyes had immature senile cataract. The incidence of intraoperative vitreous loss among residents was 2%(10/490). Vitreous loss occurred during hydrodissection [1/10(10%)], nucleus delivery [3/10(30%)], irrigation and aspiration [5/10(50%)], and intraocular lens insertion [1/10(10%)]. Multivariate stepwise Logistic regression analysis confirmed immature senile cataract [odds ratio(OR)=3.99;P=0.02], irrigation and aspiration of cortical material(OR=3.07;P=0.03), and anterior capsular extension(OR=3.22, P=0.03) as independent risk factors for vitreous loss. CONCLUSION: Immature senile cataract, irrigation and aspiration of cortical material, and anterior capsular extension are independent risk factors for vitreous loss. Our findings may serve as a guide for future trainers or residents learning MSICS.

关键词： manual small-incision cataract surgery complications of cataract surgery vitreous loss

Analysis of Natural Allelic Variation Controlling Arabidopsis thaliana Seed Germinability in Response to Cold and Dark： Identification of Three Major Quantitative Trait Loci

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Molecular Plant 2008年第1期1卷 145-154页

作者： Ping-Hong Meng Audrey Macquet Olivier Loudet Annie Marion-Poll Helen M. North Laboratoire de Biologie des Semences UMR 204 INRA AgroParisTech Institut Jean-Pierre Bourgin F-78026 Versailles Cedex France Station de Genetique et Amelioration des Plantes INRA Institut Jean-Pierre Bourgin F-78026 Versailles Cedex France present address: Institute of Horticulture Guizhou Academy of Agricultural Sciences GuiYang Guizhou Province 550006 RR. China

Light and temperature are key external factors in the control of Arabidopsis thaliana seed germination and dormancy mechanisms. Perception and response to these stimuli have to ensure that seedling emergence and growth occur at the most advantageous time for correct establishment. Analysis of over 300 Arabidopsis accessions identified 14, from 12 different geographical locations, that were able to germinate to greater than 20% at 6℃ in the dark. This natural variation was exploited to identify genetic loci responsible for cold-tolerant, dark germination. A quantitative trait loci approach was used on recombinant inbred line progeny of a cross between Bay-0 and Shahdara. Six distinct quantitative trait loci were identified, three of which were major loci, each responsible for 17-25% of the phenotypic variability in this trait. Parental phenotypes indicated that the majority of the cold-tolerant, dark-germination characteristics are related to light responses. Validation of the three major loci using heterogeneous inbred families confirmed the feasibility of fine mapping and cloning the genes at the quantitative trait loci responsible for cold-tolerant, dark germination.

关键词： Three Major Quantitative Cold and Dark Natural Allelic Variation