检索结果-南通市图书馆

Thermal-hydraulic design and transient analysis of passive cooling system for CPR1000 spent fuel storage pool

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2016年第1期27卷 156-165页

作者： Li Ge Hai-tao Wang Guo-Liang Zhang Jun-Li Gou jian-Qiang Shan Bin Zhang Bo Zhang Tian-Yu Lu Zi-jiang Yang Yuan Yuan Xi'an Jiaotong University Xi'an 710049China Shanghai Nuclear Engineering Research and Design Institute Shanghai 200233China China Nuclear Power Technology Research Institute Shenzhen 518026China

This paper proposes a design of passive cooling system for CPR1000 spent fuel pool(SFP). Our design can effectively manage the SFP temperature not to exceed80 C. Then the transient analysis of the CPR1000 SFP with designed passive cooling system is carried out in station blackout(SBO) accident by the best-estimate thermal-hydraulic system code RELAP5. The simulation results show that to maintain the temperature of CPR1000 SFP under 80 C, the numbers of the SFP and air cooling heat exchangers tubes are 6627 and 19 086, respectively.The height difference between the bottom of the air cooling heat exchanger and the top of the SFP heat exchanger is3.8 m. The number of SFP heat exchanger tubes decreases as the height difference increases, while the number of the air cooling heat exchanger tubes increases. The transient analysis results show that after the SBO accident, a stable natural cooling circulation is established. The surface temperature of CPR1000 SFP increases continually until 80 C, which indicates that the design of the passive air cooling system for CPR1000 SFP is capable of removing the decay heat to maintain the temperature of the SFP around 80 C after losing the heat sink.

关键词：热工水力设计瞬态分析冷却系统乏燃料储存

Characterizing a large outbreak of dengue fever in Guangdong Province, China

在线全文

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2016年第1期5卷 368-375页

作者： jian-Peng Xiao jian-Feng He Ai-Ping Deng Hua-Liang Lin Tie Song Zhi-Qiang Peng Xiao-Cheng Wu tao Liu Zhi-Hao Li Shannon Rutherford Wei-Lin Zeng Xing Li Wen-Jun Ma Yong-Hui Zhang Guangdong Provincial Institute of Public Health Guangdong Provincial Center for Disease Control and PreventionGuangzhouChina Guangdong Provincial Center for Disease Control and Prevention GuangzhouChina School of Public Health Sun Yat-sen UniversityGuangzhouChina Center for Environment and Population Health Griffith UniversityBrisbaneAustralia

Background:Dengue cases have been reported each year for the past 25 years in Guangdong Province,China with a recorded historical peak in 2014.This study aims to describe the epidemiological characteristics of this large outbreak in order to better understand its epidemic factors and to inform control strategies.Methods:Data for clinically diagnosed and laboratory-confirmed dengue fever cases in 2014 were extracted from the China Notifiable Infectious Disease Reporting System.We analyzed the incidence and characteristics of imported and indigenous cases in terms of population,temporal and spatial distributions.Results:A total of 45224 dengue fever cases and 6 deaths were notified in Guangdong Province in 2014,with an incidence of 47.3 per 100000 people.The elderly(65+years)represented 11.7%of total indigenous cases with the highest incidence(72.3 per 100000).Household workers and the unemployed accounted for 23.1%of indigenous cases.The majority of indigenous cases occurred in the 37th to 44th week of 2014(September and October)and almost all(20 of 21)prefecture-level cities in Guangdong were affected.Compared to the non-Pearl River Delta Region,the Pearl River Delta Region accounted for the majority of dengue cases and reported cases earlier in 2014.Dengue virus serotypes 1(DENV-1),2(DENV-2)and 3(DENV-3)were detected and DENV-1 was predominant(88.4%).Conclusions:Dengue fever is a serious public health problem and is emerging as a continuous threat in Guangdong Province.There is an urgent need to enhance dengue surveillance and control,especially for the high-risk populations in high-risk areas.

关键词： Dengue fever Epidemiology Outbreak China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

金属镁生产新工艺研究现状与进展

中国有色金属学报 2022年第6期32卷 1719-1733页

作者：车玉思杜胜敏宋建勋何季麟郑州大学材料科学与工程学院郑州450001 郑州大学河南省资源与材料工业技术研究院郑州450001

镁是地壳中含量较为丰富的金属元素,可用于助剂、添加剂与结构功能材料,有广阔的应用潜力。金属镁进入工业化生产,主要经历了电解法与热还原法,并分别衍生出各种电解法工艺与热还原法工艺。本文综述近20年国内外镁冶炼技术的研究现状,... 详细信息

镁是地壳中含量较为丰富的金属元素,可用于助剂、添加剂与结构功能材料,有广阔的应用潜力。金属镁进入工业化生产,主要经历了电解法与热还原法,并分别衍生出各种电解法工艺与热还原法工艺。本文综述近20年国内外镁冶炼技术的研究现状,详细介绍一些典型的新型镁冶炼技术工艺,其中部分工艺方法已进入中试与产业化示范阶段,为我国原镁冶炼技术的发展起到了示范引领作用。最后,针对主流生产工艺存在的问题以及当前新工艺的研究现状,提出原镁冶炼技术发展的建议与思路。

关键词：镁冶炼硅热法碳热法镁音速

Multistage Self-Assembly Strategy: Designed Synthesis of N-doped Mesoporous Carbon with High and Controllable Pyridine N Content for Ultrahigh Surface-Area-Normalized Capacitance

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

CCS Chemistry 2021年第2期3卷 870-881页

作者： Liangliang Zhang tao Wang Tu-Nan Gao Hailong Xiong Rui Zhang Zhilin Liu Shuyan Song sheng Dai Zhen-An Qiao State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchunJilin 130012 State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 Chemical Sciences Division Oak Ridge National LaboratoryOak RidgeTN 37831

Nitrogen doping could improve the performance of carbon materials in electrocatalysis,CO_(2) adsorption,and energy storage.[1]However,the control of the doping type and the amount of nitrogen(N)-doped in carbon materials in a simple and environmentally friendly way remains challenging.Herein,we report a facile,multistage,self-assembly strategy for the synthesis of two-dimensional N-doped mesoporous carbon(2D NMC)by using graphene oxide(GO)as a structure-directing agent.The resultant 2D GO@NMCs rendered quantitatively controllable mesopores(8–25 nm).The 2D GO@NMCs rendered quantitatively controllablemesopores(8–25nm),high and controllable N content(up to 19 wt%),and the percentages of pyridine and pyridone/pyrrolic N atoms were as high as 49.9%and 35.3%,respectively.Due to these unique characteristics,the fabricated 2D GO@NMCs exhibited an ultrahigh surface-areanormalized capacitance of up to 90.6μF cm−2,which was much higher than the theoretical electrochemical double-layer capacitance of activated carbon(15–25μF cm−2).Moreover,our proposed multistage self-assembly strategy is versatile,and thus,could be extended to the synthesis of one-dimensional(1D)nanotubes@NMC and zero-dimensional(0D)nanospheres@NMC materials.

关键词： multistage self-assembly mesoporous carbon nitrogen-doped carbon high pyridine nitrogen,supercapacitor

Au nanocomposite enhanced electret film for triboelectric nanogenerator

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2018年第6期11卷 3096-3105页

作者： Bao Dong Chen Wei Tang Chi Zhang Liang Xu Lai Pan Zhu Lei Jing Yang Chuan He jian Chen Long Liu tao Zhou Zhong Lin Wang Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing 100083 China CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology (NCNST) Beijing 100190 China School of Material Science and Engineering Georgia Institute of Technology Atlanta Georgia 30332 USA

A triboelectric nanogenerator （TENG） with an organic nanocomposite electret thin film as the triboelectric layer for mechanical energy harvesting was investigated systematically. In combination with corona charging, a TENG was fabricated by using embedded-nanocapacitor-structure polytetrafluoroethylene （PTFE） impregnated with gold nanoparticles （Au-NPs）. The output performances, stability, and durability of the TENGs with Au-PTFE nanocomposite films were characterized after being washed in water. It was found that the output current increases by 70% and the equivalent surface charge density （ESCD） reaches 85 μC/m^2 in comparison to the virgin PTFE film. Such outstanding performance is likely due to the equivalent nanocapacitors between the Au-NPs and PTFE molecules, which serve as nano charge traps in the nanocomposite electret film under negative high-voltage corona charging. This work not only expands the practical applications of TENGs, but also opens up new possibilities for the development of high performance triboelectric materials.

关键词： equivalent nanocapacitor structure polytetrafluoroethylene（PTFE） electret thin film gold nanoparticles equivalent surface charge density

非线性调频信号激励下非线性系统的最优共振响应

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

物理学报 2022年第5期71卷 65-72页

作者：宫涛杨建华单振王志乐刘后广中国矿业大学机电工程学院江苏省矿山机电装备重点实验室徐州221116

非线性调频(NLFM)信号在雷达、通信、信号处理中应用广泛,该类信号所激励下的非线性系统响应有着丰富的信息,通过共振来增强NLFM信号具有一定实际意义与价值.本文主要研究了受到不同类型NLFM信号所激励的非线性系统共振现象,提出了实时... 详细信息

非线性调频(NLFM)信号在雷达、通信、信号处理中应用广泛,该类信号所激励下的非线性系统响应有着丰富的信息,通过共振来增强NLFM信号具有一定实际意义与价值.本文主要研究了受到不同类型NLFM信号所激励的非线性系统共振现象,提出了实时尺度变换方法来处理高频NLFM信号,克服人为选择造成信号输出响应较差的缺点.同时,提出实时谱放大因子作为共振评价指标,准确评价NLFM信号激励下的系统共振响应,讨论系统参数对系统最优共振响应的影响,参数选择在合理的区间内即可实现最优共振响应,不仅实现信号特征的大幅增强,还保持信号时频特征的连续性.最后,将实时尺度变换方法和固定尺度变换方法进行对比,说明所提方法处理NLFM信号的优越性.

关键词：系统共振非线性调频信号信号增强实时尺度变换

CALCITONIN GENE-RELATED PEPTIDE IN THE PATHOGENESIS AND TREATMENT OF HYPERTENSION

在线全文

学校读者我要写书评

暂无评论

CHINESE MEDICAL JOURNAL 1989年第12期102卷 897-901页

作者： Tang jian Xu Dong Yuan Qi-xiao Meng Zhao-heng Chen Feng-rong Chen Ming-zhe Liu Guo-zhang Liu Li-sheng Zhang Zhao-kang LaboratoryofCardiopulmonaryEndocrinology BeijingMedicalUniversity Beijing

The present study demonstrated that the plasma calcitonin gene-related peptide (CGRP) concentration was lower but the CGRP content of abdominal aorta was higher in spontaneously hypertensive rats (SHR) than in normotensive rats (WKY), using specific CGRP radioimmunoassay (P<0.01). In eighteen patients with essential hypertension, the concentration of plasma CGRP was also much lower than that of normal subjects, suggesting that a decreased release of arterial CGRP might be a part of the pathogenesis of essential hypertension. In SHR, a significant decrease in blood pressure was found following intravenous injection of 2.5 pg/kg of CGRP; similarly, in seven patients with essential hypertension intravenous injection of CGRP (50 /μg) could induce a significant hypotensive effect. These data suggest that CGRP is a new potential drug for the treatment of essential hypertension.

关键词：

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

基于电子助力器的冗余防抱死制动算法研究

汽车工程 2022年第1期44卷 82-93页

作者：刘晓辉于良耀郑晟卢正弘宋健清华大学汽车安全与节能国家重点实验室北京100084

自主研发一种带踏板推杆的半解耦电子助力器(eBooster),基于变增益PID控制算法,对eBooster液压力进行精准控制;当车辆ABS系统失效时,通过对车辆各状态变量的估算和监测,基于eBooster对制动主缸液压力的主动调整;以冗余制动防抱死(ABS)... 详细信息

自主研发一种带踏板推杆的半解耦电子助力器(eBooster),基于变增益PID控制算法,对eBooster液压力进行精准控制;当车辆ABS系统失效时,通过对车辆各状态变量的估算和监测,基于eBooster对制动主缸液压力的主动调整;以冗余制动防抱死(ABS)功能实现为要求、制动强度和舒适性提升为目标,提出一种基于滑模控制的冗余ABS控制算法;构建整车、轮胎、eBooster、制动轮缸和冗余ABS等数学模型,进行仿真,并在试验车(哈弗H6)上完成基于eBooster的冗余ABS控制算法验证。结果表明,在常规ABS失效时,基于eBooster的冗余ABS控制算法,能在保证制动强度和舒适性的前提下,很好地实现冗余ABS功能,提高车辆安全性。

关键词：冗余防抱死制动电子助力器滑模控制制动强度舒适性

数字信号处理技术的激光传感器测量误差校准系统

在线全文

学校读者我要写书评

暂无评论

激光杂志 2022年第11期43卷 41-46页

作者：周澄许胜曹健付焕森泰州学院江苏泰州225300

为解决激光传感器测量误差校准过程中,存在的校准过程复杂以及校准精度低的缺陷,设计数字信号处理技术的激光传感器测量误差校准系统。系统包含两个激光传感器,由DSP数字信号处理器以及FPGA结合实现数据处理,数据采集卡由读数头、圆光... 详细信息

为解决激光传感器测量误差校准过程中,存在的校准过程复杂以及校准精度低的缺陷,设计数字信号处理技术的激光传感器测量误差校准系统。系统包含两个激光传感器,由DSP数字信号处理器以及FPGA结合实现数据处理,数据采集卡由读数头、圆光栅以及细分盒实现数据采集,误差校准模块通过细分辨向计数功能以及高频滤波功能,对激光传感器测量误差校准的信号处理,通过平移矢量以及旋转矩阵建立优化的目标函数,实现激光传感器测量误差的全局校准。系统测试结果表明,所设计系统误差校准过程简单,不同测量角度时的误差校准标准差均低于0.7,校准精度高,加入高斯噪声情况下仍具有较高的误差校准性能。

关键词：数字信号处理技术激光传感器测量误差校准系统