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两种雾化无铅焊锡粉末特性及钎焊接头显微组织

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材料热处理学报 2011年第1期32卷 28-33页

作者：许天旱王党会西安石油大学材料科学与工程学院陕西西安710065 西安交通大学材料科学与工程学院陕西西安710049

采用扫描电镜(SEM)和激光粒度分析仪研究了无铅焊锡粉末Sn3Ag2.8Cu和Sn3Ag2.8Cu-0.1Ce的特性诸如球形度、粒度分布、润湿性及钎焊接头的显微组织,并与对应合金的润湿性及钎焊接头显微组织进行了对比。结果表明:Sn3Ag2.8Cu和Sn3Ag2.8Cu-0... 详细信息

采用扫描电镜(SEM)和激光粒度分析仪研究了无铅焊锡粉末Sn3Ag2.8Cu和Sn3Ag2.8Cu-0.1Ce的特性诸如球形度、粒度分布、润湿性及钎焊接头的显微组织,并与对应合金的润湿性及钎焊接头显微组织进行了对比。结果表明:Sn3Ag2.8Cu和Sn3Ag2.8Cu-0.1Ce粉末都具有较好的粒度分布和球形度;与传统Sn37Pb粉末和Sn3Ag2.8Cu粉末相比,Sn3Ag2.8Cu-0.1Ce粉末均具有更好的润湿性;在与铜基板的钎焊中,Sn3Ag2.8Cu-0.1Ce粉末的扩散层比Sn3Ag2.8Cu粉末更薄,但两种粉末与铜基板形成的扩散层均比其对应合金与铜基板的扩散层更厚。因此,Sn3Ag2.8Cu-0.1Ce粉末具有更好的综合性能。

关键词： Sn-Ag-Cu系无铅焊锡粉末粉末特性润湿性显微组织

导液管突出高度对Sn-Ag-Cu无铅焊锡粉末特性的影响

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材料热处理学报 2010年第2期31卷 21-25页

作者：许天旱王党会西安石油大学材料科学与工程学院陕西西安710065 西安交通大学材料科学与工程学院陕西西安710049

利用自行设计的超音速雾化制粉装置,研究了导液管突出高度对Sn3Ag2.8Cu无铅焊锡粉末有效雾化率、粒度分布、球形度及氧含量的影响。结果表明:在一定雾化条件下,导液管突出高度为4 mm,雾化粉末具有最佳球形度、表面光滑度及粒度分布,同... 详细信息

利用自行设计的超音速雾化制粉装置,研究了导液管突出高度对Sn3Ag2.8Cu无铅焊锡粉末有效雾化率、粒度分布、球形度及氧含量的影响。结果表明:在一定雾化条件下,导液管突出高度为4 mm,雾化粉末具有最佳球形度、表面光滑度及粒度分布,同时具有较高的有效雾化率和最低的氧含量;和Sn37Pb粉末相比,在与Cu基板的钎焊中,利用Sn3Ag2.8Cu粉末配制的焊锡膏与铜基板之间形成的IMC更厚,且更不规则;当导液管突出高度从4 mm增加至5 mm,粉末更细,有效雾化率提高,但粒度分布变差,粉末表面更粗糙;当导液管突出高度从4 mm减小至2 mm,粉末有效雾化率降低,粒度分布变差。因此,在本试验条件下,导液管突出高度最佳为4 mm。

关键词：无铅焊锡粉末气体雾化导液管突出高度粉末特性

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面向系统芯片测试的微处理器结构设计

计算机工程与应用 2009年第13期45卷 81-83,89页

作者：王党辉西北工业大学计算机学院西安710072

采用内嵌微处理器作为测试控制器来测试系统芯片可以提高测试精度和速度,降低测试成本。提出在微处理器结构上做改进,设计了测试数据接口和测试数据解压单元,可以对SOC测试起支持作用。实验结果表明所增加的硬件在电路面积上可接受,对... 详细信息

采用内嵌微处理器作为测试控制器来测试系统芯片可以提高测试精度和速度,降低测试成本。提出在微处理器结构上做改进,设计了测试数据接口和测试数据解压单元,可以对SOC测试起支持作用。实验结果表明所增加的硬件在电路面积上可接受,对电路性能没有影响,而且对微处理器的正常功能没有任何影响。

关键词：系统芯片测试微处理器结构

Co-doped cryptomelane-type manganese oxide in situ grown on a nickel foam substrate for high humidity ozone decomposition

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Journal of Environmental Sciences 2025年第2期148卷 529-540页

作者： Haoyuan Liang Xu wang hui wang Zhenping Qu Key Laboratory of Industrial Ecology and Environmental Engineering School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

Monolithic catalysts with excellent O_(3)catalytic decomposition performance were prepared by in situ loading of Co-doped KMn_(8)O_(16)on the surface of nickel *** triple-layer structure with Co-doped KMn_(8)O_(16)/Ni6MnO_(8)/Ni foam was grown spontaneously on the surface of nickel foam by tuning the molar ratio of KMnO_(4)to Co(NO_(3))_(2)·6H_(2)O ***,the formed Ni6MnO_(8)structure between KMn_(8)O_(16)and nickel foam during in situ synthesis process effectively protected nickel foam from further etching,which significantly enhanced the reaction stability of *** optimum amount of Co doping in KMn_(8)O_(16)was available when the molar ratio of Mn to Co species in the precursor solution was 2:*** the Mn2Co1 catalyst had abundant oxygen vacancies and excellent hydrophobicity,thus creating outstanding O_(3)decomposition *** O_(3)conversion under dry conditions and relative humidity of 65%,90%over a period of 5 hr was 100%,94%and 80%with the space velocity of 28,000 hr^(−1),*** in situ constructed Co-doped KMn_(8)O_(16)/Ni foam catalyst showed the advantages of low price and gradual applicability of the preparation process,which provided an opportunity for the design of monolithic catalyst for O_(3)catalytic decomposition.

关键词： Co-doped cryptomelane-type manganese O3 decomposition High humidity Nickel foam Monolithic catalyst

Comparative Study of the Characteristics of the Basal Plane Stacking Faults of Nonpolar a-Plane and Semipolar (1122) GaN

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Chinese Physics Letters 2012年第1期29卷 254-256页

作者： XU Sheng-Rui LIN Zhi-Yu XUE Xiao-Yong LIU Zi-Yang MA Jun-Cai JIANG Teng MAO Wei wang dang-hui ZHANG Jin-Cheng HAO Yue Key Lab of Wide Band-Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi’an 710071

Nonpolar (1120) and semipolar (1122) GaN are grown on r-plane and m-plane sapphire by MOCVD to investigate the characteristics of basal plane stacking faults (BSFs).Transmission electron microscopy reveals that the density of BSFs for the semipolar (1122) and nonpolar a-plane GaN template is 3×10^(5) cm^(-1) and 8×10^(5) cm^(-1),*** semipolar (1122) GaN shows an arrowhead-like structure,and the nonpolar a-plane GaN has a much smoother morphology with a streak along the *** nonpolar (11(2)0) and semipolar (1122) GaN have very strong BSF luminescence due to the optically active character of the BSFs.

关键词： GaN sapphire MOCVD

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金佳12采区对旋式主风机选型设计

煤矿机械 2006年第8期27卷 24-25页

作者：王党辉盘江煤电新井开发公司贵州盘县553536

根据金佳12采区的实际情况,阐述了主风机的选型方法,确定主风机风叶安装角度,电动机功率计算方法,以及应用变频技术控制风机运行参数,从而提倡在煤矿中应用节约型技术。

关键词：对旋式主风机选型变频技术

纤锌矿GaN外延层薄膜热膨胀行为的变温Raman散射研究

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物理学报 2016年第13期65卷 55-61页

作者：王党会许天旱宋海洋西安石油大学材料科学与工程学院西安710065

本文对纤锌矿结构GaN外延层薄膜的热膨胀行为进行了研究,结合热膨胀系数的物理意义与变温Raman散射时声子频移的变化规律,研究了热膨胀系数与变温Raman散射之间的关系.结果表明:通过测量Raman声子E_2(high),A_1(TO)和E_1(TO)频移与温度... 详细信息

本文对纤锌矿结构GaN外延层薄膜的热膨胀行为进行了研究,结合热膨胀系数的物理意义与变温Raman散射时声子频移的变化规律,研究了热膨胀系数与变温Raman散射之间的关系.结果表明:通过测量Raman声子E_2(high),A_1(TO)和E_1(TO)频移与温度之间的线性关系,结合相应声子Gruneisen参数的涵义,可对纤锌矿结构GaN外延层薄膜在一定温度范围内的热膨胀系数进行测量.本文提供了一种表征纤锌矿结构GaN外延层薄膜热膨胀行为的有效方法,为进一步研究III族氮化物外延层薄膜在生长过程中热膨胀系数的匹配、降低外延层薄膜中的位错密度并提高发光二极管的发光效率提供了理论依据.

关键词：外延层薄膜热膨胀系数 Gruneisen参数变温Raman散射

Statistical Research on Megahertz-peaked Spectra Pulsars

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Research in Astronomy and Astrophysics 2025年第1期25卷 116-134页

作者： Hong-Bing Cai Li Chen Shi-dang Li Kai wang Hang Liu JSNU SPBPU Institute of Engineering & SINO RUSSIAN Institute Jiangsu Normal University School of Physics and Electronic Engineering Jiangsu Normal University

Megahertz-peaked spectra(MPS) pulsars are referred as cases whose radio spectra turn over around 100 MHz. We identified 53 MPS pulsars based on the spectral data from the literature, and statistically analyzed the spatial location distribution, the magnetic field-period distribution, peak frequencies, spectral indices, and dispersion measures of these MPS pulsars. We found that there is a strong positive correlation between the dispersion measures and the peak frequencies of MPS pulsars, and negative correlations of the dispersion measures with spectral indices and the ages are also found. Such correlations suggest that the interstellar medium is an important factor that affects observational properties of MPS pulsars.

关键词： (stars:) pulsars: general ISM: general radio continuum: general

Effect of pouring time on microstructure and mechanical properties of centrifugal cast Ti-46Al alloy tubes

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China Foundry 2025年第1期22卷 65-74页

作者： Gang Huang Qian dang Cong-cong Su Jing Zhao Chi Zhang Guo-huai Liu Zhao-dong wang The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

The grain size of TiAl alloy castings prepared by traditional casting process is coarse,thus showing poor mechanical *** this study,a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was *** research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings,employing both experimental approaches and ProCast simulation *** findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed *** the condition of pouring temperature of 1,600℃,rotation speed of 800 r·min^(-1) and pouring time of 6 s,the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa,and the tensile strength at 800℃ reaches 705 MPa,which is significantly higher than that of traditional as-cast Ti-Al alloy.

关键词： vacuum induction melting centrifugal casting Ti-46Al alloy pouring time Ti-Al alloy tubes

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