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The In-Sn-Ni alloys of various compositions were prepared and annealed at 160°C and 240°C. No ternary compounds were found;
however, most of the binary compounds had extensive ternary solubility. There was a continuous solid solution between the
Ni3Sn phase and Ni3In phase. The Sn-In/Ni couples, made of Sn-In alloys with various compositions, were reacted at 160°C and 240°C and formed
only one compound for all the Sn-In alloys/Ni couples reacted up to 8 h. At 240°C, Ni28In72 phase formed in the couples made with pure indium, In-10at.%Sn and In-11at.%Sn alloys, while Ni3Sn4 phase formed in the couples made of alloys with compositions varied from pure Sn to In-12at.%Sn. At 160°C, except in the
In/Ni couple, Ni3Sn4 formed by interfacial reaction. 相似文献
4.
本文介绍印制板液态感光阻焊油墨的工艺流程、工艺控制,并对生产中较常出现的几种质量问题进行讨论,进而提出解决措施。 相似文献
5.
The reaction between the Sn-Ag-Cu solders and Ni at 250°C for 10 min and 25 h was studied. Nine different Sn-Ag-Cu solders,
with the Ag concentration fixed at 3.9 wt.% and Cu concentrations varied between 0.0–3.0 wt.%, were used. When the reaction
time was 10 min, the reactions strongly depended on the Cu concentration. At low-Cu concentrations (≦0.2 wt.%), only a continuous
(Ni1−xCux)3Sn4 layer formed at the interface. When the Cu concentration increased to 0.4 wt.%, a continuous (Ni1−xCux)3Sn4 layer and a small amount of discontinuous (Cu1−yNiy)6Sn5 particles formed at the interface. When the Cu concentration increased to 0.5 wt.%, the amount of (Cu1−yNiy)6Sn5 increased and (Cu1−yNi6)6Sn5 became a continuous layer. Beneath this (Cu1−yNiy)6Sn5 layer was a very thin but continuous layer of (Ni1−xCux)3Sn4. At higher Cu concentrations (0.6–3.0 wt.%), (Ni1−xCux)3Sn4 disappeared, and only (Cu1−yNiy)6Sn5 was present. The reactions at 25 h also depended strongly on the Cu concentration, proving that the strong concentration
dependence was not a transient phenomenon limited to a short reaction time. The findings of this study were rationalized using
the Cu-Ni-Sn isotherm. This study shows that precise control over the Cu concentration in solders is needed to produce consistent
results. 相似文献
6.
综述了环氧树脂基的PCB与无铅化组装的兼容性问题。经过大量试验表明,常规的FR-4基材和双氰胺固化的高Tg基材是不能满足无铅化组装要求的,而采用酚醛固化的中等-Tg的环氧树脂基材是可能成为无铅化组装用基材的。同时,PCB制造过程也起着重要的作用。PCB设计和再(回)流焊的加热梯度也影响着无铅化的性能。 相似文献
7.
面向表面组装工艺技术的PCB焊盘设计 总被引:1,自引:1,他引:0
尽管电子设计类软件已相当先进和方便,而且更新速度也很快,但是仍然无法满足各个层次的设计人员的需求,特别是适合各种元素封装形式的焊盘设计库并不能让设计和制造者满意,为了在此方面对PCB设计有所帮助,从印制电路板焊盘的设计方法入手,针对表面组装工艺技术特点,分析了PCB焊盘对PCA可靠性的影响因素,并根据相关的质量要求提出了较为简便的设计方案。 相似文献
8.
Resilient metal spring silicone-matrix conducting composites for separable interconnections in electronics were fabricated
by the impregnation of silicone into a preform comprising randomly oriented C-shaped Cu-Be springs and a small proportion
of Sn-Pb solder, which served to connect the springs at some of their intersections. Composites containing 6.1-9.8 vol.% total
filler exhibited volume electrical resistivity 0.5-1.0 mΩ.cm and contact resistivity (with copper) 11-17 mΩ.cm2. A compressive stress of about 30 kPa was needed for the low contact resistivity to be reached. The volume 17-26% and the
contact resistivity increased by 5% after heating in air at 130-150°C for seven days. Composites containing <9 vol.% total
filler showed no stress relaxation for seven days at 6.0% strain. 相似文献
9.
Microstructure and mechanical properties of Pb-free solder alloys for low-cost electronic assembly: A review 总被引:5,自引:0,他引:5
Judith Glazer 《Journal of Electronic Materials》1994,23(8):693-700
Lead-free solders, including Sn-58Bi, Sn-52In, and Sn-3.5Ag, are potential replacements for Sn-37Pb solder in low-cost electronic
assembly. This paper reviews the literature on the microstructure and mechanical properties of these alloys. Because of the
processing and testing conditions, many of the data are not predictive for electronic assembly applications. However, eutectic
Sn-Bi seems to have properties approaching those of eutectic Sn-Pb under most conditions, while eutectic Sn-In seems far inferior
in most respects. Eutectic Sn-Ag has many promising characteristics, but its relatively high melting temperature may preclude
its use for this type of application. 相似文献
10.
Sungho Jin 《Journal of Electronic Materials》2003,32(12):1366-1370
In packaging of microelectromechanical systems (MEMS), optical, and electronic devices, there is a need to directly bond a
wide variety of inorganic materials, such as oxides, nitrides, and semiconductors. Such applications involve hermetic-sealing
components, three-dimensional MEMS assembly components as well as active semiconductor or optical components, dielectric layers,
diffusion barriers, waveguides, and heat sinks. These materials are known to be very difficult to wet and bond with low melting-point
solders. New Sn-Ag- or Au-Sn-based universal solders doped with a small amount of rare-earth (RE) elements have been developed,
which now allow direct and powerful bonding onto the surfaces of various MEMS, optical, or electronic device materials. The
microstructure, interface properties, and mechanical behavior of the bonds as well as the potential packaging applications
of these new solder materials for MEMS and optical fiber devices are described. Various packaging-related structural, thermal,
or electrical issues in MEMS are also discussed. 相似文献