检索结果-南通市图书馆

Investigation on ignition characteristics of charring conductive polymers stimulated by electric energy

Chinese Journal of Aeronautics 2024年第10期37卷 68-82页

作者： Zhiyuan ZHANG Hanyu DENG Wenhe LIAO Yantao PU Ping CAO School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Anhui Hongxing electrical Polytron Technologies inc. Hefei 231135China

The arc ignition based on charring conductive polymers has advantages of simple structure,low ignition power consumption and restart capacity,which bringing it broadly application prospect in hybrid propulsion system of micro/nano *** order to optimize the performance of arc ignition system,it is essential to have a deeper understanding of the ignition processes and ignition characteristics of charring conductive *** this paper,the thermal decomposition,electrical conductivity and thermal conductivity characteristics of charring conductive polymers with different conductive additives and matrix materials were comprehensively *** experimental investigation was conducted to determine the ignition behaviors and characteristics of different charring conductive polymers in a visual ignition *** experiment result showed that the ignition delay and external energy required for ignition are negatively correlated with voltage and initial temperature of the ignition grain,but positively correlated with oxidizer flow *** with charring conductive polymers containing multi-walled carbon nanotube,the ignition delay of charring conductive polymers with carbon black is significantly higher and the pyrolysis time is relatively ***,the ignition and initial flame propagation of charring conductive polymers with carbon black is more violent and more inc.ined to carbon particle ***,the restart characteristic of different charring conductive polymers was *** ignition delay and external energy required for ignition of different charring conductive polymers all reduced with the inc.easing of the number of ***,the ignition characteristics would not change a lot after repeated ignition.

关键词： Micro/nano satellite hybrid rocket motors Arc ignition Charring conductive polymer Ignition process Ignition characteristic Restart characteristic

来源：

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

Accurate Distinc.ion of Weak and Strong AC Grids for Emerging Hierarchical-Infeed LCC-UHVDC Systems

引用

CSEE Journal of Power and Energy Systems 2024年第2期10卷 772-777页

作者： Hao Xiao Xianzhong Duan Yi Zhang Department of electrical and Computer Engineering University of ManitobaWinnipeg R3T 2N2ManitobaCanada State Key Laboratory of Advanced Electromagnetic Engineering and Technology Hubei Electric Power Security and High Efficiency Key LaboratorySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina RTDS Technologies inc. Winnipeg R3T 2E1ManitobaCanada

Distinc.ion of weak and strong AC grids for emerging hierarchical-infeed LCC-UHVDC systems is important for planning and operation departments. However, accuracy of earlier distinc.ion methods is limited as they were developed by empirical reasoning without rigorous theoretical analysis. Hence in this letter, hierarchical-infeed interactive effective short-circuit ratio (HIESCR) index is first used for strength evaluation of HIDC systems with complex inter-inverter interactions considered. Boundary HIESCR (BHIESCR) is also introduced in the proposed distinc.ion method of weak and strong AC grids. That is, weak (or strong) AC grids are, respectively, identified when HIESCR is less (or greater) than BHIESCR. Second, it is shown BHIESCR remains almost unchanged as 3.0 versus various system parameters and rated operation variables based on rigorous theoretical analysis. This salient feature makes the proposed method more accurate than earlier methods. Finally, the proposed method is validated by simulations based on the PSCAD/EMTDC program.

关键词： Hierarchical-Infeedinteractive effective short-circuit ratio hierarchical-infeed LCC-UHVDC systems inter-inverter interactions strong AC grids weak AC grids

来源：

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

The Origin of electric Charge in Quantum Gravity

引用

Journal of Modern Physics 2024年第4期15卷 511-535页

作者： Edwin Eugene Klingman Cybernetic Micro Systems Inc. San Gregorio CA USA

A model fermion has been produced in a theory of quantum gravity that establishes the existence of a mass gap and half-integral spin. The third requirement for the fermion is electric charge. We herein develop a dualism-based analysis that explains the origin of charge at the fermion scale in a primordial field theory of quantum gravity.

关键词： Duality Topology Parallel Transport Particle Genesis Primordial Field Self-Interaction Equations Yang-Mills Gravity

来源：

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

Efficiency improvement by using metal–insulator‑semiconductor structure in InGaN/GaN micro‑light‑emitting diodes

引用

Frontiers of Optoelectronics 2024年第1期17卷 77-84页

作者： Jian Yin David Hwang Hossein Zamani Siboni Ehsanollah Fathi Reza Chaji Dayan Ban Department of electrical and Computer Engineering Waterloo Institute NanotechnologyUniversity of WaterlooWaterlooON N2L 3G1Canada Vuereal inc. 440 Philip StreetUnit 100WaterlooON N2L 5R9Canada

InGaN/GaN micro-light-emitting diodes(micro-LEDs)with a metal–insulator-semiconductor(MIS)structure on the sidewall are proposed to improve *** this MIS structure,a sidewall electrode is deposited on the insulating layer-coated sidewall of the device mesa between a cathode on the bottom and an anode on the ***(EL)measurements of fabricated devices with a mesa diameter of 10μm show that the application of negative biases on the sidewall electrode can inc.ease the device external quantum efficiency(EQE).In contrast,the application of positive biases can decrease the *** band structure analysis reveals that the EQE is impacted because the application of sidewall electric fields manipulates the local surface electron density along the mesa sidewall and thus controls surface Shockley–Read–Hall(SRH)*** suggested strategies,reducing insulator layer thickness and exploring alternative materials,can be implemented to further improve the EQE of MIS micro-LEDs in future fabrication.

关键词： Micro-LED GaN EQE improvement Micro-fabrication

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Energy modeling and optimization of building condenser water systems with all-variable speed pumps and tower fans:A case study

引用

Building Simulation 2024年第7期17卷 1085-1111页

作者： Yong Cao Chuang Wang Sheng Wang Xiao Fu Xinguo Ming School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation Zhuhai 519070China GREE electric Appliances Inc.of ZhuhaiZhuhai 519070China School of Environment and Energy Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China Beijing Advanced Innovation Centerfor Future Urban Design Beijing University of Civil Engineering and ArchitectureBeijing 100044China

The emergence of building condenser water systems with all-variable speed pumps and tower fans allows for inc.eased efficiency and flexibility of chiller plants in partial load operation but also inc.eases the control complexity of condenser water *** study aims to develop an integrated modeling technique for evaluating and optimizing the energy performance of such a condenser water *** proposed system model is based on the semi-physical semi-empirical chiller,pump,and cooling tower models,with capabilities of fully considering the hydraulic and thermal interactions in the condenser water loop,being solved analytically and much faster than iterative solvers and supporting the explicit optimization of the pump and tower fan frequency.A mathematical approach,based on the system model and constrained optimization technique,is subsequently established to evaluate the energy performance of a typical dual setpoint-based variable speed strategy and find its energy-saving potential and most efficient operation by jointly optimizing pumps and tower *** all-variable speed chiller plant from Wuhan,China,is used for a case study to validate the system model’s accuracy and explore its *** results showed that the system model can accurately simulate the condenser water system’s performance under various operating *** optimizing the frequencies of pumps and tower fans,the total system energy consumption can be reduced by 12%–13%compared to the fixed dual setpoint-based strategy with range and approach setpoints of 4℃and 2℃.In contrast,the energy-saving potential of optimizing the cooling tower sequencing is insignificant.A simple joint speed control method for optimizing the pumps and tower fans emerged,i.e.,the optimal pump and fan frequency are linearly correlated(if both are non-extremes)and depend on the chiller part load ratio only,irrespective of the ambient wet-bulb temperature and chilled water supply *** was also foun

关键词： all-variable speed chiller plant model-based optimization hydraulic and thermal coupling analytical solution dual setpoint-based variable speed control optimal joint speed control

来源：

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

TEM Observation of Si0.99C0.01 Thin Films with Arsenic-Ion-, Boron-Ion-, and Silicon-Ion-Implantation Followed by Rapid Thermal Annealing

引用

Journal of Materials Science and Chemical Engineering 2017年第1期5卷 15-25页

作者： Junji Yamanaka Shigenori Inoue Keisuke Arimoto Kiyokazu Nakagawa Kentarou Sawano Yasuhiro Shiraki Atsushi Moriya Yasuhiro Inokuchi Yasuo Kunii Center for Crystal Science and Technology University of Yamanashi Kofu Japan Advanced Research Laboratories Tokyo City University Tokyo Japan hitachi kokusai electric inc. Toyama Japan

Strained Si and its related materials, such as strained SiGe and strained silicon-carbon alloy (Si-C), are receiving tremendous interest due to their high carrier mobility. In this study we carry out a basic investigation of the change in microstructure of ion-implanted Si-C solid solution caused by rapid thermal annealing, because it is very important to realize a field-effect transistor made of this new material. The microstructures of arsenic-ion-, boron-ion-, and silicon-ion-implanted Si0.99C0.01 specimens upon thermal annealing are observed using transmission electron microscopy, and it is revealed that the rate of solid-state crystallization of ion-implanted Si-C is slower than that of the ion-implanted Si.

关键词： Strained Heterodevice Silicon-Carbon Alloy Ion Implantation Transmission Electron Microscopy

来源：

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

Thermal physiological response to local heating and cooling during sleep

引用

Frontiers of Architectural Research 2012年第1期1卷 51-57页

作者： Yu Hibino Shuichi Hokoi Katsuaki Yoshida Satoru Takada Masanori Nakajima Miho Yamate KVOtO University Japan Kobe University Japan The Kansai electric Power Co. Inc. Japan

For a healthy and productive life, good steep is essential, which has prompted studies on how comfortable sleep can be achieved. Understanding the relationship between thermal environment and physiological responses such as skin and core temperatures, and psychological responses such as thermal and sleep sensations is necessary to identify the most suitable thermal environment for steep. As an energy-saving and practical method of creating the most appropriate thermal environment for sleep, local heating or cooling is sometimes used, which takes into consideration the differences in local thermal responses. We performed this study to identify the most effective thermal environment for inducing comfortable sleep by identifying the physiological responses during sleep on the basis of sleep experiments conducted under local body heating or cooling conditions. We also used a human thermal model, which can be applied for predicting physiological responses. In the experiments, the feet of the subject were the primary area to be heated or cooled, which was achieved by installing a flexible duct with an outlet placed close to the subject＇s feet and inlet connected to an air conditioner. Differences in the fluctuation of body temperature and sleep stage depended on the airflow direction from the duct to the feet. When air was blown downward towards the feet, body temperature decreased and the subject was able to sleep well. Measured skin and core temperatures were calculated using an improved 27-node human thermal model that was originally developed for use in subjects who are not in steep. Although skin

关键词： Sleep Thermal environ-ment Local air conditioning Physiologicalresponse Human thermal mode[

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Participation of large-scale wind power generation in power system frequency regulation

引用

Chinese Science Bulletin 2013年第36期58卷 4557-4565页

作者： SUN HaiShun LIU Ju WEN JinYu CHENG ShiJie LUO Cheng YAO LiangZhong State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and Technology Midwest Independent Transmission System Operator inc. China electric Power Research Institute

The initiative participation of wind power generators in power system frequency regulation is an inevitable demand to ensure power system safe operation with large-scale wind power ***,it is princ.pally difficult for conventional wind turbines to participate in power system frequency *** this reason,solution to this problem is becoming a hot topic in the current *** paper systematically reviews the relevant research progresses in the control strategies and the capability assessment of using wind power generators in the power system frequency regulation,inc.uding the comparing among the emulating inertia control,the droop control,the rotor speed control,the pitch angle control and the coordinated ***,future research in this area is pointed out in the paper.

关键词：风力发电机电力系统频率调节控制策略风力涡轮机安全运行惯性控制转速控制

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optimal Energy Flow and Nodal Energy Pricing in Carbon Emission-embedded Integrated Energy Systems

引用

CSEE Journal of Power and Energy Systems 2018年第2期4卷 179-187页

作者： Tao Jiang Hongwei Deng Linquan Bai Rufeng Zhang Xue Li Houhe Chen Department of electrical Engineering Northeast Electric Power UniversityJilin 132012Jilin ProvinceChina ABB inc. RaleighNC 27606USA

Green energy is driving the evolutions of energy industry and carbon emission is becoming an important *** the inc.easing couplings among various energy sectors,this paper investigates multi-period optimal energy flow and energy pricing in carbon-emission embedded integrated energy systems,inc.uding electricity,natural gas,and district heating ***,an optimal scheduling model of integrated energy systems was proposed in this *** models of DC power flow,natural gas pipeline flow and heating network energy flow are presented and linearized for the optimization *** gas-fired generators and combined heat and power(CHP)units are modeled as coupling components of electricitygas and electricity-heating ***,based on the optimal scheduling model,the locational marginal prices(LMP)for electricity,natural gas and heating network are ***,the carbon emission caused by energy production has been taken into account in the optimal scheduling and energy pricing ***,case studies on a combined network consisting of IEEE 39-bus system,Belgium 20-node natural gas system and 6-node heating system demonstrate the effectiveness of the proposed model and the impacts of carbon emission on system scheduling and LMP.

关键词： Carbon emission district heating LMP natural gas optimal energy flow

来源：

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

The effects of portable cooling systems on thermal comfort and work performance in a hot environment

引用

Building Simulation 2021年第6期14卷 1667-1683页

作者： Jieyu Tang Yu Liu Hui Du Li Lan Yuxiang Sun Jialin Wu School of Design Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Air Conditioning Equipment and System Energy Conservation Zhuhai 517907China Gree electric Appliances inc. Zhuhai 517907China

There are some special spaces in which there is no air conditioning or the people are in move,thus exposing people to a hot *** this study,portable cooling systems were proposed and their effects on thermal comfort and work performance were investigated at an air temperature of 32°*** conditions were established:cool air towards breathing zone(A),chest and back cooling(B)#combined cooling(C)and no cooling(D).Twenty-eight subjects were exposed to the four conditions in a counterbalanced *** each exposure they performed tasks and made subjective assessments,while multiple physiological parameters were *** with no cooling(D),cool air towards breathing zone(A)and chest and back cooling(B)improved work performance by 17.5%and 19.25%,respectively,while decreased the subjects'thermal sensation,skin temperature,and heart *** the two cooling systems were combined(C),larger improvements in thermal comfort and work performance were achieved than no cooling(D);the mean thermal sensation rating decreased from 2.4 to 0.7;work performance inc.eased by up to 33%,and physiological parameters inc.uding skin temperature,pulse,heart rate and salivary alpha-amylase significantly *** present results suggest that the proposed portable cooling systems could maintain thermal comfort and work performance in a hot environment,while potentially improve air quality for some special spaces.

关键词： work performance thermal comfort cool air towards breathing zone chest and back cooling portable cooling systems

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：