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热辐射特征参数对快堆锥形顶盖空间换热特性影响的研究

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核科学与工程 2024年第1期44卷 55-62页

作者：冯佳琪陆道纲张钰浩于宗玉华北电力大学核科学与工程学院北京102206 非能动核能安全技术北京市重点实验室北京102206

池式钠冷快堆的钠池内充满高温液态钠,其上方覆盖有氩气,高温液态钠主要通过辐射换热及对流换热的方式向快堆主容器上部结构及氩气空间传递热量,其换热特性及其影响因素十分复杂。辐射发射率及液态钠蒸发形成的气溶胶层对主容器上部结... 详细信息

池式钠冷快堆的钠池内充满高温液态钠,其上方覆盖有氩气,高温液态钠主要通过辐射换热及对流换热的方式向快堆主容器上部结构及氩气空间传递热量,其换热特性及其影响因素十分复杂。辐射发射率及液态钠蒸发形成的气溶胶层对主容器上部结构的热工水力特性会造成一定影响。因此,为保证主容器上部结构在不同温度载荷下的安全性与稳定性,十分必要获取不同辐射发射率及不同气溶胶层分布下的温度分布。本研究建立大型池式钠冷快堆主容器上部锥形顶盖空间(以下简称“锥顶盖”)数值计算模型,开展数值模拟计算,得到不同发射率及气溶胶层厚度影响下锥顶盖的温度场。研究结果表明,发射率越高,锥顶盖斜肩及氩气空间温度越高;当气溶胶层存在于靠近钠液面的高度范围时(0~0.2 m),增加其厚度可使氩气空间局部温度升高,但对锥顶盖斜肩温度影响有限。发射率增高53%,则辐射换热量增加31.47%,格拉晓夫数(Gr)减少19.29%,辐射换热效果增强,自然对流效果减弱;气溶胶层高度由0增加到0~0.1 m时,对辐射换热量的吸收增加22.68%,格拉晓夫数(Gr)减少19.29%,气溶胶层高度由0~0.1 m增加到0~0.2 m时,透过气溶胶层的辐射换热量减少了0.04%,格拉晓夫数(Gr)增加了0.9%,辐射换热效果减弱,自然对流效果加强。

关键词：快堆锥形顶盖空间辐射换热自然对流发射率吸收系数

Analysis of the Dynamic System of Wave Glider with a Towed Body

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Journal of Ocean University of China 2020年第3期19卷 519-524页

作者： zhang Jiakun CHANG zongyu LU Guiqiao ZHENG Zhongqiang zhang Zhonglin College of Engineering Ocean University of ChinaQingdao 266100China Key Laboratory of Ocean Engineering of Shandong Province Qingdao 266100China College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China

Mobile observation platforms are widely used in oceanographic and marine resource exploration and other applications. Wave Glider is a mobile platform that can transform wave energy into locomotion power and overcome the bottleneck of low energy supply. Wave Glider has recently been applied to tow underwater sensors fulfilling observation tasks. In this paper, the dynamic system of Wave Glider with a towed body is studied by applying multibody mechanics, and the relevant motion conditions of the system are investigated. Dynamic models of Wave Glider with a towed body and tether are first developed individually and then integrated into a whole model. The numerical method is used to obtain the dynamic responses and assess performance of the towed body pulled by the submerged glider of Wave Glider. The effects of sea state, mass of the towed body, and length of the towed cable are investigated on the basis of simulation results. This work can be used for the design and analysis of Wave Glider-towed body systems.

关键词： Wave Glider towed system motion response dynamic analysis

Control strategy for wayside supercapacitor energy storage system in railway transit network

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Journal of Modern Power Systems and Clean Energy 2014年第2期2卷 181-190页

作者： zongyu GAO Jianjun FANG Yinong zhang Di SUN College of Automation of Beijing Union University Beijing 100101China School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China

This paper discusses the control strategy for energy management in railway transit network with wayside(substation)supercapacitor(SC)energy storage system(ESS).Firstly,the structure of the wayside energy storage system is ***,the model of energy storage system is built and the control strategy is ***,in order to estimate the required energy storage system,a useful method is proposed to predict the instantaneous regenerative energy magnitude which is delivered to each ***,the ESS configuration for each substation is determined.A simplified mathematical model of the whole metro network is established and the main features of the control strategy are *** simulations show the efficacy of suggested control strategy and the energy saving obtained for railway transit network.

关键词： Supercapacitor(SC) Energy storage system(ESS) Regeneration failure Control strategy Railway transit network

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电脱盐的改造及影响效果

天然气与石油 2004年第1期22卷 34-37页

作者：侯宗玉张百军中国石化股份公司济南分公司山东济南250101

胜利原油的引进导致原油脱后盐含量超标 ,通过筛选破乳剂并进行流程改造 ,降低脱后原油含盐量 ,进一步降低催化原料和催化剂的金属含量 ,减少催化剂单耗 ,降低操作压力 ,效益显著。

关键词：破乳剂脱盐盐含量催化裂化原料金属含量催化剂单耗

一种采用调制晶体管和有源反馈电阻的新型差分有源电感

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电子器件 2024年第3期47卷 597-602页

作者：邱宗玉张万荣北京工业大学信息学部微电子学院北京100124

提出了一种品质因数-频率(Q-f)特性、电感值-频率(L-f)特性增强和线性度高的新型差分有源电感。它主要由正跨导器、负跨导器、调制晶体管和有源反馈电阻共4个单元构成,其中,调制晶体管的外部配置了电压调控端并串接于差分结构的负跨导... 详细信息

提出了一种品质因数-频率(Q-f)特性、电感值-频率(L-f)特性增强和线性度高的新型差分有源电感。它主要由正跨导器、负跨导器、调制晶体管和有源反馈电阻共4个单元构成,其中,调制晶体管的外部配置了电压调控端并串接于差分结构的负跨导器的漏极,来实现电感值的调节和增大。有源反馈电阻的外部配置了电压调控端并串接于负跨导器的漏极和正跨导器的栅极之间,来实现Q值的调节和增大。负跨导器也配置了外部电压调控端,来实现对频带的调节;进一步地,调制晶体管和有源反馈电阻也改善了有源电感的线性度。最终,通过4个单元的相互配合和3个外部调控端电压的协同调节,可实现4种有源电感的优异综合性能:(1)在同一频率下,Q峰值相对于L值可独立调节;(2)在多频点下取得高且基本恒定的Q峰值;(3)在宽工作频带内可对L值进行大范围调节,同时Q值能够保持较高的值;(4)高的L值线性度。验证结果表明,在3.85 GHz下,Q峰值可在963~3374之间调谐,调谐率为111.2%,而电感值变化率仅为0.28%;在3.10 GHz、3.55 GHz和3.70 GHz三个频点下,分别取得了1916、1923和1821的高Q峰值,变化率仅为5.4%;在2.65 GHz~3.6 GHz频带内,L值的调谐范围均大于31%,且Q值始终大于10;电感的线性度高达-9 dBV。

关键词：差分有源电感有源反馈电阻高线性度

Chemical and Isotopic Responses to Intensive Groundwater Abstraction and Its Implications on Aquifer Sustainability in Shijiazhuang,China

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Journal of Earth Science 2017年第3期28卷 523-534页

作者： Zhongshuang Cheng Yongbo zhang Chen Su zongyu Chen Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China

The stress imposed on groundwater resources due to intensively exploited aquifer has resulted in groundwater depletion in the North China Plain（NCP）. Management of groundwater resources needs to understand the changes or dynamic responses due to the exploitation. The response of groundwater systems to intensive exploitation and groundwater availability were assessed by the combined use of conventional hydrochemical data and environmental isotopes in Shijiazhuang, NCP. The generally increased concentration of total dissolved solids（TDS）, major cation and anion of groundwater in the past 40 years indicated high vulnerability of aquifer system but a short turn over time by intensive groundwater exploitation, which also was proved by changes of groundwater renewal rate estimated by tritium. The vertical distribution of tritium in aquifers showed that the active groundwater recharge zone has been extended from the depth of 100 to ~150 m since 1985, indicating an enhancement of active groundwater flushing of local groundwater system due to intensive groundwater abstraction. The enrichment trend of δ^（18）O and δ~2H value with groundwater abstraction, suggested the impacts of local recharge from irrigation return. The increase concentrations of nitrate with time indicated high aquifer vulnerability. A comprehensive effort should be developed for effective management strategies that ensure long-term, stable, and flexible water supplies to meet water demands in the NCP.

关键词： isotope renewal rate North China Plain groundwater

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转筒干燥器中物料运动模型的研究现状

化工机械 2009年第3期36卷 190-194,214页

作者：赵改菊吴静尹凤交盛成张宗宇山东省科学院工业节能研究中心山东大学

综述了近年来国内外关于转筒干燥器物料运动模型的研究现状,分析了各种模型的特点及适用性,并对其今后的发展方向进行了展望。

关键词：转筒干燥器运动模型抄板停留时间

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基于晶体管的运算放大器实验项目设计

实验科学与技术 2020年第1期18卷 47-52页

作者：侯长波张宗昱余文鑫张朝柱司伟建洪艳哈尔滨工程大学信息与通信工程学院

晶体管放大电路是电子电路综合实验课程的重难点,具有极强的实践意义,对提高学生的电子系统设计和实践能力起着重要作用。该文提出了一个利用晶体管制作运算放大器的选题,将模拟电子技术中典型的晶体管放大电路基本囊括,包括恒流源差放... 详细信息

晶体管放大电路是电子电路综合实验课程的重难点,具有极强的实践意义,对提高学生的电子系统设计和实践能力起着重要作用。该文提出了一个利用晶体管制作运算放大器的选题,将模拟电子技术中典型的晶体管放大电路基本囊括,包括恒流源差放电路、恒流源电路、共射放大电路、互补输出电路等;然后通过理论计算与Multisim仿真设计了系统方案和电路参数;最后实测和分析了各项技术指标。实验结果表明,设计方案清晰,展现了晶体管放大电路的原理以及工作过程,教学效果良好,可为其他高校开设相关课程提供一定借鉴和帮助。

关键词：电子电路综合实验运算放大器晶体管 Multisim

Extraction mechanism and separation behaviors of low-concentration Nd^(3+) and Al^(3+) in P507-H_(2)SO_(4) system

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Journal of Rare Earths 2022年第6期40卷 952-957,I0004页

作者： Hongyuan zhang Longsheng Zhao Xudong Zheng Depeng Liu zongyu Feng Yongqi zhang Xiaowei Huang National Engineering Research Center for Rare Earth Materials GRINM Group Co.Ltd.Beijing 100088China General Research Institute for Nonferrous Metals Beijing 100088China Grirem Advanced Materials Co. Ltd.Beijing 100088China Rare Earth Functional Materials(Xiong’an)Innovation Center Co. Ltd.Baoding 071700China

In order to clarify the solvent extraction and separation behaviors of rare earths and impurity of Al during the extraction and enrichment of low-concentration leach solution of ion-adsorption rare earth ore,the extraction mechanism and separation behaviors of Nd^(3+)and Al^(3+)in the Nd_(2)(SO_(4))_(3)-AI_(2)(SO_(4))_(3) mixed solution using P507 were studied in this *** extraction of Nd^(3+)and Al^(3+)follows the cation exchange *** the increase of the equilibrium pH,β_(Nd/Al) in the extraction of the Nd_(2)(SO_(4))_(3)-Al_(2)(SO_(4))_(3) mixed solution using P507 is always higher than that in the extraction of single Nd_(2)(SO_(4))_(3) and Al_(2)(SO_(4))_(3) *** can be attributed to the fact that the extraction of Nd^(3+)using P507 is much faster than that of Al^(3+),and Al^(3+)is more prone to be hydrolyzed at lower pH.β_(Nd/Al) in the extraction of the Nd_(2)(SO_(4))_(3)-Al_(2)(SO_(4))_(3) mixed solution decreases gradually with the increase of mixing time within the equilibrium pH range of *** extraction of Nd^(3+)using P507 is much faster than that of Al^(3+),but the stability of Al^(3+)-Ioaded organic phase is better than that of Nd^(3+)-loaded organic phase,thus Nd^(3+)in the Nd^(3+)-loaded organic phase is gradually replaced by Al^(3+)in the aqueous phase with the increase of mixing time.

关键词： Ion-adsorption rare earth ore Low-concentration rare earth Aluminum Extraction mechanism Separation factor