检索结果-南通市图书馆

Science China(Technological Sciences) 2014年第12期57卷 2487-2499页

作者： zhang jia jie QU Zhi Guo XU Hui Jin TAO Wen Quan MOE Key Laboratory of Thermo-Fluid Science and Engineering School of Energy and Power EngineeringXi'an Jiaotong University

Fully developed flow and heat transfer in metal-foam filled tube with uniform wall temperature(UWT) is semi-analytically investigated based on the Brinkman–Darcy model and the two-equation model, in which the inertia term, axial conduction, and thermal dispersion are ignored. A two-dimensional numerical simulation that adopts the full governing equations is also conducted to analyze the effects of neglected terms on flow and thermal transport performance by comparing with the semi-analytical solution. The effects of the relevant parameters and thermal boundary conditions including UWT and uniform heat flux(UHF) on the heat transfer characteristics are discussed based on the semi-analytical solution. The results show that the inertia term has a significant effect on the prediction of pressure drop, but has a relatively mild effect on Nusselt number. The axial conduction has significant effect on the Nusselt number at lower Reynolds number, and the effects of thermal dispersion can be neglected when the thermal conductivity ratio between fluid and solid is remarkably smaller for air/metal foam as example(kf/ks<3×10-3). The predicted Nusselt number of the semi-analytical solution is about 8% to 15% lower than that of the numerical solution with full model in the range of 4×10-5

关键词： metal foams semi-analytical uniform wall temperature numerical simulation heat transfer

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo zhang jie Dang jia Guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Ideal Bi‑Based Hybrid Anode Material for Ultrafast Charging of Sodium‑Ion Batteries at Extremely Low Temperatures

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第3期17卷 152-167页

作者： jie Bai jian Hui jia Yu Wang Chun Cheng Yang Qing jiang Key Laboratory of Automobile Materials(Jilin University) Ministry of EducationSchool of Materials Science and EngineeringJilin UniversityChangchun 130022People’s Republic of China

Sodium-ion batteries have emerged as competitive substitutes for low-temperature applications due to severe capacity loss and safety concerns of lithium-ion batteries at−20°C or ***,the key capability of ultrafast charging at ultralow temperature for SIBs is rarely ***,a hybrid of Bi nanoparticles embedded in carbon nanorods is demonstrated as an ideal material to address this issue,which is synthesized via a high temperature shock *** a hybrid shows an unprecedented rate performance(237.9 mAh g^(−1)at 2 A g^(−1))at−60℃,outperforming all reported SIB anode *** with a Na_(3)V_(2)(PO_(4))_(3)cathode,the energy density of the full cell can reach to 181.9 Wh kg^(−1)at−40°*** on this work,a novel strategy of high-rate activation is proposed to enhance performances of Bi-based materials in cryogenic conditions by creating new active sites for interfacial reaction under large current.

关键词： Bi nanoparticles High temperature shock High-rate activation Ultrafast charging Low-temperature sodium-ion batteries

Dynamic behaviors of graphene platelets-reinforced metal foam piezoelectric beams with velocity feedback control

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 63-80页

作者： jie CHEN Xinyue zhang Mingyang FAN School of Mathematics Statistics and Mechanics Beijing University of Technology College of Mechanical & Energy Engineering Beijing University of Technology

Graphene platelets(GPLs)-reinforced metal foam structures enhance the mechanical properties while maintaining the lightweight characteristics of metal foams. Further bonding piezoelectric actuator and sensor layers on the surfaces of GPLs-reinforced metal foam beams enables active vibration control, greatly expanding their applications in the aerospace industry. For the first time, this paper investigates the vibration characteristics and active vibration control of GPLs-reinforced metal foam beams with surfacebonded piezoelectric layers. The constant velocity feedback scheme is used to design the closed-loop controller including piezoelectric actuators and sensors. The effects of the GPLs on the linear and nonlinear free vibrations of the beams are numerically *** Newmark-β method combined with Newton's iteration technique is used to calculate the nonlinear responses of the beams under different load forms including harmonic loads,impact loads, and moving loads. Additionally, special attention is given to the vibration reduction performance of the velocity feedback control on the responses of the beam.

关键词： Piezoelectric actuators

A Cross-Multi-Domain Trust Assessment Authority Delegation Method Based on Automotive Industry Chain

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2025年第1期82卷 407-426页

作者： Binyong Li Liangming Deng jie zhang Xianhui Deng School of Cybersecurity(Xin Gu Industrial College) Chengdu University of Information TechnologyChengdu610225China Advanced Cryptography and System Security Key Laboratory of Sichuan Province Chengdu610225China SUGON Industrial Control and Security Center Chengdu610225China

To solve the challenges of connecting and coordinating multiple platforms in the automotive industry and to enhance collaboration among different participants,this research focuses on addressing the complex supply relationships in the automotive market,improving data sharing and interactions across various platforms,and achieving more detailed integration of data and *** propose a trust evaluation permission delegation method based on the automotive industry *** proposed method combines smart contracts with trust evaluation mechanisms,dynamically calculating the trust value of users based on the historical behavior of the delegated entity,network environment,and other factors to avoid malicious node attacks during the permission delegation *** also introduce strict control over the cross-domain permission granting and revocation mechanisms to manage the delegation path,prevent information leakage caused by malicious node interception,and effectively protect data integrity and *** analysis shows that this method meets the realtime requirements of collaborative interaction in the automotive industry chain and provides a feasible solution to permission delegation issues in the automotive industry chain,offering dynamic flexibility in authorization and scalability compared to most existing solutions.

关键词： Automotive industry chain cross-domain access block chain delegate authority trust assessment

A Review on Thermal Management of Li-ion Battery:from Small-Scale Battery Module to Large-Scale Electrochemical Energy Storage Power Station

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

Journal of Thermal Science 2025年第1期34卷 1-23页

作者： CHEN Zhifeng jia Li YIN Liaofei DANG Chao REN Honglei zhang Zhiqiang Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong University

Li-ion battery is an essential component and energy storage unit for the evolution of electric vehicles and energy storage technology in the ***,in order to cope with the temperature sensitivity of Li-ion battery and maintain Li-ion battery safe operation,it is of great necessary to adopt an appropriate battery thermal management system(BTMS).In this paper,the current main BTM strategies and research hotspots were discussed from two aspects:small-scale battery module and large-scale electrochemical energy storage power station(EESPS).The practical application situation,advantages and disadvantages,and the future development trend of each heat dissipation method(air,liquid,PCM,heat pipe,hybrid cooling) were described in *** them,the air cooling and liquid cooling were reviewed in-depth based on the engineering *** PCM,heat pipe and hybrid cooling were reviewed extensively based on the latest *** research provides a comprehensive understanding for the BTMS in all scales.

关键词： battery thermal management cooling methods large-scale electrochemical energy storage power station small-scale battery module

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin He Lin-Sen Ye Xiao-Feng Yang jia-jia zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

相变微胶囊复合板相变传热数值研究

工程热物理学报 2018年第5期39卷 1078-1084页

作者：符云笛屈治国张嘉杰西安交通大学能源与动力工程学院热流科学与工程教育部重点实验室西安710049

本文以相变微胶囊复合板隔热组件为研究对象,基于焓法方程建立了蓄热/隔热型耦合相变传热数值模型,预测了板内的温度分布、相界面移动等响应特征,系统地分析了Stefan数及相变温度区间对传热的影响。结果表明:相变微胶囊板内固相界面的... 详细信息

本文以相变微胶囊复合板隔热组件为研究对象,基于焓法方程建立了蓄热/隔热型耦合相变传热数值模型,预测了板内的温度分布、相界面移动等响应特征,系统地分析了Stefan数及相变温度区间对传热的影响。结果表明:相变微胶囊板内固相界面的移动速度大于液相界面,固相界面消失后,液相界面移动明显加速;固、液相界面移动速度随Stefan数的增大而增快,同时板内整体温度水平升高;固相界面移动速度随着相变温度区间的增大而增快,但相变温度区间对相变材料完全熔化所需时间影响不大。

关键词：相变微胶囊复合板隔热结构数值计算相变传热

阳离子交换色谱-抑制电导检测法测定过渡金属

在线全文

学校读者我要写书评

暂无评论

浙江大学学报（理学版） 2009年第2期36卷 191-193,198页

作者：张嘉捷王雪浙江大学化学系浙江杭州310028

采用离子色谱抑制电导检测若干过渡金属离子.由于淋洗液抑制后成中性,过渡金属离子易发生水解形成氢氧化物沉淀而无法采用抑制电导检测,实验中采用在常规强酸淋洗液中加入两性离子,用于控制抑制后淋洗液的pH值.经过实验,在Waters IC-Pak... 详细信息

采用离子色谱抑制电导检测若干过渡金属离子.由于淋洗液抑制后成中性,过渡金属离子易发生水解形成氢氧化物沉淀而无法采用抑制电导检测,实验中采用在常规强酸淋洗液中加入两性离子,用于控制抑制后淋洗液的pH值.经过实验,在Waters IC-Pak C M/D柱上(150mm×3.9mm,ID)确定淋洗液条件为6.5mmol·L-1甲基磺酸(MSA)和10mmol·L-14-羟基乙基哌嗪乙磺酸(HEPES),Co2+、Ni2+、Zn2+和Cu2+等4种过渡金属离子在抑制电导检测下得到了检测信号并与碱金属、铵离子和碱土金属离子获得了较好的分离.在该实验条件下,方法具有较好的灵敏度(检测下限1.31～31.2μg·L-1)和重现性(时间RSD小于0.86%,峰面积RSD小于5.09%).

关键词：两性离子过渡金属离子抑制电导检测

在线全文

学校读者我要写书评

暂无评论

柱后衍生离子色谱法分析米粉中植酸

浙江大学学报（理学版） 2005年第2期32卷 201-203页

作者：张嘉捷朱岩浙江大学化学系浙江杭州310028

报道采用阴离子交换分离,0 .1% Fe Cl3and 2 % HCl O4 在线柱后衍生,在2 90 nm波长检测,快速、方便地检测米粉中痕量植酸,该分离体系采用阴离子交换柱(Dionex Ion Pac AS7,2 5 0×4 m m I.D.) ,以1.0 m L / min流速的0 .2 5 mol/ L HNO... 详细信息

报道采用阴离子交换分离,0 .1% Fe Cl3and 2 % HCl O4 在线柱后衍生,在2 90 nm波长检测,快速、方便地检测米粉中痕量植酸,该分离体系采用阴离子交换柱(Dionex Ion Pac AS7,2 5 0×4 m m I.D.) ,以1.0 m L / min流速的0 .2 5 mol/ L HNO3为流动相,获得良好的分离效果而且具有较好的重现性,方法的测定范围为2～5 0 0 m g/ L ,检出限为0 .5 6 m g/ L ,回收率为98.3%～10 1.5 % 。

关键词：植酸柱后衍生离子色谱