检索结果-南通市图书馆

Preventing formation of intermetallic compounds in ultrasonic-assisted Sn soldering of Mg/Al alloys through pre-plating a Ni coating layer on the Mg substrate

引用

Journal of Magnesium and Alloys 2024年第2期12卷 726-741页

作者： Yingzong liu yuanxing li Hui Chen Zongtao Zhu Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031PR China

Magnesium and aluminum alloys are widely used in various industries because of their excellent properties,and their reliable connection may increase application of *** compounds(IMCs)affect the joint performance of Mg/*** this study,AZ31 Mg alloy with/without a nickel(Ni)coating layer and 6061 Al alloy were joined by ultrasonic-assisted soldering with Sn-3.0Ag-0.5Cu(SAC)*** effects of the Ni coating layer on the microstructure and mechanical properties of Mg/Al joints were systematically *** Ni coating layer had a significant effect on formation of the Mg_(2)Sn IMC and the mechanical properties of Mg/Al *** blocky Mg_(2)Sn IMC formed in the Mg/SAC/Al joints without a Ni coating *** content of the Mg_(2)Sn IMC increased with increasing soldering temperature,but the joint strength *** joint without a Ni coating layer fractured at the blocky Mg_(2)Sn IMC in the solder,and the maximum shear strength was 32.2 *** pre-plating Ni on the Mg substrate,formation of the blocky Mg_(2)Sn IMC was inhibited in the soldering temperature range 240–280℃and the joint strength ***,when the soldering temperature increased to 310℃,the blocky Mg_(2)Sn IMC precipitated again in the *** electron microscopy showed that some nano-sized Mg_(2)Sn IMC and the(Cu,Ni)_(6)Sn_(5)phase formed in the Mg(Ni)/SAC/Al joint soldered at 280℃,indicating that the Ni coating layer could no longer prevent diffusion of Mg into the solder when the soldering temperature was higher than 280℃.The maximum shear strength of the Mg(Ni)/SAC/Al joint was 58.2 MPa for a soldering temperature of 280℃,which was 80.7%higher than that of the Mg/SAC/Al joint,and the joint was broken at the Mg(Ni)/SAC ***-plating Ni is a feasible way to inhibit formation of IMCs when joining dissimilar metals.

关键词： Ultrasonic-assisted soldering Mg_(2)Sn Ni coating layer Shear strength

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

酸水汽提装置回流系统设备腐蚀原因分析及对策

引用

智能城市应用 2024年第7期7卷 116-118页

作者：李元星宁夏煤业集团有限公司煤制油分公司宁夏银川750002

本篇文章对酸水汽提装置回流系统设备的腐蚀问题进行了深入分析,从宏观腐蚀特征、回流凝液样检测、设备材质分析以及腐蚀原因分析等方面入手,全面了解系统的腐蚀状况。通过对设备表面腐蚀形态的观察,以及回流凝液样的化学分析和腐蚀产... 详细信息

本篇文章对酸水汽提装置回流系统设备的腐蚀问题进行了深入分析,从宏观腐蚀特征、回流凝液样检测、设备材质分析以及腐蚀原因分析等方面入手,全面了解系统的腐蚀状况。通过对设备表面腐蚀形态的观察,以及回流凝液样的化学分析和腐蚀产物检测,可获取了关键的腐蚀信息;设备材质分析帮助评估材料的耐腐蚀性能,而腐蚀原因分析则综合考虑各方面因素,明确导致腐蚀的主要因素。这一深入的分析为制定有针对性的预防和修复措施提供了科学依据,以提高系统的稳定性和可靠性。

关键词：酸水汽提装置回流系统设备腐蚀原因及对策

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

湿陷性黄土地层浅埋大跨度隧道高压水平旋喷桩预支护应用技术

引用

甘肃科技 2024年第4期40卷 10-13页

作者：李元兴中电建建筑集团有限公司甘肃兰州730000

高压水平旋喷桩的应用和隧道施工技术的发展密不可分,尤其在覆土较薄的松软地层中,隧道掘进开挖极易引起坍塌和地面沉陷等问题,给施工的推进带来了极大的困难。20世纪80年代高压水平旋喷技术首次应用于隧道的预支护,随着我国岩土工程技... 详细信息

高压水平旋喷桩的应用和隧道施工技术的发展密不可分,尤其在覆土较薄的松软地层中,隧道掘进开挖极易引起坍塌和地面沉陷等问题,给施工的推进带来了极大的困难。20世纪80年代高压水平旋喷技术首次应用于隧道的预支护,随着我国岩土工程技术的不断发展,该项技术趋于成熟,得到了更加广泛的应用。文章以西北地区特有的湿陷性黄土地质环境为研究对象,研究双侧壁导坑开挖工法中使用高压水平旋喷桩预支护的应用技术,通过实际案例阐述该技术的应用范围、施工工艺以及缺陷处理方法,以期补充该技术在特定地质环境中的空白,为类似项目的施工提供一定的参考和借鉴。

关键词：高压水平旋喷桩湿陷性黄土大跨度隧道双侧壁导坑法施工工艺

来源：

维普期刊数据库博看期刊

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

地空协同场景下加权模糊聚类用户簇划分方法

引用

计算机应用 2024年第5期44卷 1555-1561页

作者：黄天宇李远兴陈昊郭紫佳魏明军华北理工大学人工智能学院河北唐山063210 河北省工业智能感知重点实验室河北唐山063210

为了解决应急通信场景下使用无人机作为空中基站进行辅助通信时涉及的无人机基站部署策略中的用户簇划分问题,在兼顾无人机基站性能和用户体验的条件下,提出一种基于特征加权的模糊聚类(Improved FCM)算法。首先,根据每个无人机基站的... 详细信息

为了解决应急通信场景下使用无人机作为空中基站进行辅助通信时涉及的无人机基站部署策略中的用户簇划分问题,在兼顾无人机基站性能和用户体验的条件下,提出一种基于特征加权的模糊聚类(Improved FCM)算法。首先,根据每个无人机基站的信号覆盖范围和最大服务用户数量的性能约束,针对随机分布条件下的用户簇在划分过程中算法计算量大不易收敛的问题,提出一种基于距离加权的特征加权节点数据投影算法;其次,针对同一用户处于多个簇有效范围内时用户划分的有效性和无人机基站资源的最大化利用问题,提出一种基于用户位置和无人机基站负载均衡的价值加权算法。实验结果表明,所提方法充分满足无人机基站的服务性能约束,且与几何分形法(GFA)、谱聚类(Sp-C)等算法相比,特征加权模糊聚类算法获得的平均负载率和覆盖比是最优的,分别达到了0.774和0.0263,因此,该算法可为应急通信场景下的用户簇划分问题提供一种可行的解决方案。

关键词：地空协同应急通信无人机辅助通信无人机基站部署用户簇划分特征加权模糊C均值聚类

来源：

维普期刊数据库

同方期刊数据库

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

Photocatalytic oxidation of methane to methanol over zinc titanate supported silver catalysts

引用

Journal of Rare Earths 2024年第5期42卷 899-906,I0004页

作者： Yuyan Gan Jinbi Huang Qian Lv Yanru li lizhi Wu YU Tang yuanxing Fang Pengfei Zhu li Tan Institute of Molecule Catalysis and In-Situ/Operando Studies State Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou350108China School of Environmental Science and Engineering Shaanxi University of Science and TechnologyXi'an 70021China

The direct activation of methane under mild condition to achieve highly selective of oxygenates is a challenging *** this study,a well dispersed silver supported ZnTiO_(3) catalyst was prepared to achieve selective preparation of methanol from methane and water under mild condition.X-ray diffraction,transmission electron microscopy and X-ray photoelectron spectroscopy characterizations demonstrate that silver species are uniformly dispersed on ZnTiO_(3) surface in the form of metallic silver *** photoelectric characterizations reveal that the addition of silver species enhances light absorption and promotes charge separation of the *** the reaction conditions of 50℃and 3 MPa,the methanol is obtained as the only liquid product over the designed Ag/ZnTiO_(3) catalyst under light *** this photocatalytic process,the holes generated by ZnTiO_(3) activate water to produce intermediate·OH,which further reacts with methane to synthesize *** silver species as co-catalysts extend the light absorption range of ZnTiO_(3) as well as promote charge separation.

关键词： Photocatalytic Methane oxidation Zinc titanate Silver Methanol

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

S-scheme heterojunction of crystalline carbon nitride nanosheets and ultrafine WO_(3)nanoparticles for photocatalytic CO_(2)reduction

引用

Journal of Environmental Sciences 2024年第6期140卷 103-112页

作者： Gongjie Chen Ziruo Zhou Bifang li Xiahui lin Can Yang yuanxing Fang Wei lin Yidong Hou Guigang Zhang Sibo Wang State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFujian 350116China

Highly crystalline carbon nitride polymers have shown great opportunities in overall water photosplitting;however,their mission in light-driven CO_(2)conversion remains to be *** this work,crystalline carbon nitride(CCN)nanosheets of poly triazine imide(PTI)embedded with melon domains are fabricated by KCl/liCl-mediated polycondensation of dicyandiamide,the surface of which is subsequently deposited with ultrafine WO_(3)nanoparticles to construct the CCN/WO_(3)heterostructure with a S-scheme *** characterizations have been conducted to reveal the compositions and structures of the S-scheme CCN/WO_(3)hybrid,featuring strengthened optical capture,enhanced CO_(2)adsorption and activation,attractive textural properties,as well as spatial separation and directed movement of light-triggered charge *** mild conditions,the CCN/WO_(3)catalyst with optimized composition displays a high photocatalytic activity for reducing CO_(2)to CO in a rate of 23.0μmol/hr(i.e.,2300μmol/(hr·g)),which is about 7-fold that of pristine CCN,along with a high CO selectivity of 90.6%against ***,it also manifests high stability and fine reusability for the CO_(2)conversion *** CO_(2)adsorption and conversion processes on the catalyst are monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS),identifying the crucial intermediates of CO_(2)^(*)-,COOH^(*)and CO^(*),which integrated with the results of performance evaluation proposes the possible CO_(2)reduction mechanism.

关键词： Crystalline carbon nitride Photocatalysis CO_(2)reduction S-scheme WO_(3)

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

lithiophilic li-Si alloy-solid electrolyte interface enabled by high-concentration dual salt-reinforced quasi-solid-state electrolyte

引用

Journal of Energy Chemistry 2024年第8期95卷 216-230,I0005页

作者： yuanxing Zhang ling Zhang Zhiguang Zhao Yuxiang Zhang Jingwen Cui Chengcai liu Daobin Mu Yuefeng Su Borong Wu Feng Wu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 401120China Collaborative Innovation Center of Electric Vehicles in Beijing Beijing 100081China

Solid polymer electrolytes(SPEs)are urgently required to achieve practical solid-state lithium metal batteries(LMBs)and lithium-ion batteries(liBs),Herein,we proposed a mechanism for modulating interfacial conduction and anode interfaces in high-concentration SPEs by *** electrolyte exhibits superior ionic conductivity and remarkable interface compatibility with salt-rich clusters:(1)polymer-plastic crystal electrolyte(P-PCE,TPU-SN matrix)dissociates ion pairs to facilitate li+transport in the electrolyte and regulates li^(+)diffusion in the *** crosslinking structure of the matrix compensates for the loss of mechanical strength at high-salt concentrations;(2)dual-anion TFSI^(-)_(n)-DFBOP^(-)_(m)in the li^(+)solvation sheath facilitates facile li^(+)desolvation and formation of salt-rich clusters and is conducive to the formation of li conductive segments of TPU-SN matrix;(3)theoretical calculations indicate that the decomposition products of liDFBOP form SEI with lower binding energy with liF in the SN system,thereby enhancing the interfacial electrochemical redox kinetics of SPE and creating a solid interface SEI layer rich in *** a result,the optimized electrolyte exhibits an excellent ionic conductivity of9.31×10^(-4)S cm^(-1)at 30℃and a broadened electrochemical stability up to 4.73 *** designed electrolyte effectively prevents the formation of li dendrites in li symmetric cells for over 6500 h at0.1 mA cm^(-2).The specific li-Si alloy-solid state half-cell capacity shows 711.6 mAh g^(-1)after 60 cycles at 0.3 A g^(-1).Excellent rate performance and cycling stability are achieved for these solid-state batteries with li-Si alloy anodes and NCM 811 *** 811‖Prelithiated silicon-based anode solid-state cell delivers a discharge capacity of 195.55 mAh g^(-1)and a capacity retention of 97.8%after 120 *** 811‖li solid-state cell also delivers capacity retention of 84.2%after 450 cycles.

关键词： Prelithiation li-Si alloy anode Solid-state electrolyte SEI layer

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

Industry Associations Play a Pivotal Role in Ushering in a New Era for International Exchanges

引用

International Understanding 2015年第1期 33-37页

作者： li yuanxing

After more than 30 years of reform and opening up,significant changes have taken place in China’s economic ties with the rest of the *** order to bring China’s opening up drive to a new level in line with the latest... 详细信息

关键词： cooperation globalization German proactive steps companies exchanges Berlin director Guangdong

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

Facilitating prelithiation of silicon carbon anode by localized high-concentration electrolyte for high-rate and long-cycle lithium storage

引用

Carbon Energy 2024年第6期6卷 216-233页

作者： yuanxing Zhang Borong Wu Jiaying Bi Xinyu Zhang Daobin Mu Xin-Yu Zhang ling Zhang Yao Xiao Feng Wu School of Materials Science and Engineering Beijing Institute of TechnologyBeijingChina Chongqing Innovation Center Beijing Institute of TechnologyChongqingChina College of New Energy Xi′an Shiyou UniversityXi′anChina Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhouChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjinChina

The commercialization of silicon-based anodes is affected by their low initial Coulombic efficiency(ICE)and capacity decay,which are attributed to the formation of an unstable solid electrolyte interface(SEI)***,a feasible and cost-effective prelithiation method under a localized highconcentration electrolyte system(LHCE)for the silicon-silica/graphite(Si-SiO_(2)/C@G)anode is designed for stabilizing the SEI layer and enhancing the *** thin SiO_(2)/C layers with-NH2 groups covered on nano-Si surfaces are demonstrated to be beneficial to the prelithiation process by density functional theory calculations and electrochemical *** SEI formed under LHCE is proven to be rich in ionic conductivity,inorganic substances,and flexible organic ***,faster li+transportation across the SEI further enhances the prelithiation effect and the rate performance of Si-SiO_(2)/C@G *** also leads to uniform decomposition and high stability of the SEI with abundant organic *** a result,the prepared anode shows a high reversible specific capacity of 937.5 mAh g^(-1)after 400 cycles at a current density of 1 *** 811‖li-SSGLHCE full cell achieves a high-capacity retention of 126.15 mAh g^(-1)at 1 C over 750 cycles with 84.82%ICE,indicating the great value of this strategy for Si-based anodes in large-scale applications.

关键词： localized high-concentration electrolytes prelithiation SEI layer silicon anode

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

旋转滑动弧涡流器点火探索试验

引用

航空动力学报 2023年第4期38卷 769-776页

作者：彭畅新杨浩刘逸博姜世界李元星李炜中国航发湖南动力机械研究所湖南株洲412002

基于中小发燃烧室常用的斜切孔+径向叶片式涡流器,结合滑动弧的产生位置,开展了4种方案的旋转滑动弧涡流器设计及加工,并完成了冷态放电试验及点火试验验证。放电试验结果表明:4种方案的涡流器均能在预设位置产生稳定的旋转滑动弧。三... 详细信息

基于中小发燃烧室常用的斜切孔+径向叶片式涡流器,结合滑动弧的产生位置,开展了4种方案的旋转滑动弧涡流器设计及加工,并完成了冷态放电试验及点火试验验证。放电试验结果表明:4种方案的涡流器均能在预设位置产生稳定的旋转滑动弧。三头部点火试验结果表明:方案4的点火效果最好,其最小点火油气比低于常规点火方法。方案2次之,方案3仅能在较低的参考速度下实现燃烧室的点火,方案1的点火效果最差。滑动弧当地的气流速度及油气分布对点火效果影响显著,建议滑动弧处的气流速度不超过20 m/s。

关键词：燃烧室旋转滑动弧涡流器点火油气比

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

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：