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101.
Multiwalled carbon nanotube (MWCNT) displays peculiar electrical behavior, with its nano-configuration consisting of exceptional graphene flakes. As for MWCNTs blended into polymethyl methacrylate (PMMA), sandwiched Ni/MWCNTs(2 wt%):PMMA/ITO was manufactured to investigate into the multi-bit resistive switching regarding the turn-on compliance current as well as the thickness of the active layer. It bears ternary write-once read-many-times (WORM) memory, whose current proportionality between ON-state and OFF-state can exceed 107. Moreover, the memory performance, covering the long-term retention (>106 s), better endurance (>1012 cycles) and device-to-device profiles, confirms the excellent ternary memory of MWCNTs:PMMA. Concentration on multi-bit resistive switching in respect of MWCNTs underlies performance enhancement, higher integration and advanced architecture. 相似文献
102.
Very thin films, less than 100 nm-thick, are used in a variety of applications, including as catalysts and for thin film reactions
to form patterned silicides in electronic devices. Because of their high surface to volume ratio, these very thin films are
subject to cap-illary instability and can agglomerate well below their melting temperatures. In order to develop a general
understanding of agglomeration in very thin films, we have studied initially continuous and patterned films of gold on fused
silica substrates. Two in situ techniques were used to monitor agglomeration: 1) heating and video recording in a transmission
electron microscope, and 2) measurement of the intensity of laser light transmitted through a sample heated in a furnace.
Electron microscopy allowed inves-tigation of the role of the microstructure of the Au film and analysis of light transmis-sion
during heating allowed determination of temperature-dependent and film-thick-ness-dependent agglomeration rates. These results
will be described along with models for the agglomeration process. 相似文献
103.
介绍了在外壳检验中,应用X射线荧光光谱法(XRF),对外壳的镀涂层厚度进行测试;探讨了金属外壳镀镍涂层厚度的测试方法;论述了应用X射线荧光光谱法正确测量外壳镀层的方法。 相似文献
104.
During the reflowing of Sn-9Zn solder ball grid array (BGA) packages with Au/Ni/Cu and Ag/Cu pads, the surface-finished Au
and Ag film dissolved rapidly and reacted with the Sn-9Zn solder to form a γ3-AuZn4/γ-Au7Zn18 intermetallic double layer and ε-AgZn6 intermetallic scallops, respectively. The growth of γ3-AuZn4 is prompted by further aging at 100°C through the reaction of γ-Au7Zn18 with the Zn atoms dissolved from the Zn-rich precipitates embedded in the β-Sn matrix of Sn-9Zn solder BGA with Au/Ni/Cu
pads. No intermetallic compounds can be observed at the solder/pad interface of the Sn-9Zn BGA specimens aged at 100°C. However,
after aging at 150°C, a Ni4Zn21 intermetallic layer is formed at the interface between Sn-9Zn solder and Ni/Cu pads. Aging the immersion Ag packages at 100°C
and 150°C caused a γ-Cu5Zn8 intermetallic layer to appear between ε-AgZn6 intermetallics and the Cu pad. The scallop-shaped ε-AgZn6 intermetallics were found to detach from the γ-Cu5Zn8 layer and float into the solder ball. Accompanied with the intermetallic reactions during the aging process of reflowed Sn-9Zn
solder BGA packages with Au/Ni/Cu and Ag/Cu pads, their ball shear strengths degrade from 8.6 N and 4.8 N to about 7.2 N and
2.9 N, respectively. 相似文献
105.
The intermetallic compounds formed in Sn3Ag0.5Cu and Sn3Ag0.5Cu0.06Ni0.01Ge solder BGA packages with Ag/Cu pads are investigated.
After reflow, scallop-shaped η-Cu6Sn5 and continuous planar η-(cu0.9Ni0.1)6Sn5 intermetallics appear at the interfaces of the Sn3Ag0.5Cu and Sn3Ag0.5Cu0.06Ni0.01Ge solder joints, respectively. In the
case of the Sn3Ag0.5Cu specimens, an additional ε-Cu3Sn intermetallic layer is formed at the interface between the η-Cu6Sn5 and Cu pads after aging at 150°C, while the same type of intermetallic formation is inhibited in the Sn3Ag0.5Cu0.06Ni0.01Ge
packages. In addition, the coarsening of Ag3Sn precipitates also abates in the solder matrix of the Sn3Ag0.5Cu0.06Ni0.01Ge packages, which results in a slightly higher
ball shear strength for the specimens. 相似文献
106.
We report the Schottky performance and thermal reliability of a wide bandgap InGaP layer in contact with a Cu/Au metallic
system. An effective Schottky barrier height of 0.97 eV and an ideality factor of 1.21 can be achieved. The thermal reliability
of the resultant Schottky barrier diodes was analyzed using Auger electron spectroscopy and atomic force microscopy. The thermal
reliability could be main tained up to 450°C. The failure mechanism was attributable to the decomposition of the InGaP layer
and the interdiffusion of the chemical elements at higher temperature. Insensitive photoresponsivity with the in cident optical
power was found for the resultant Au/Cu-metal-semiconductor-metalphotodetectors (MSM-PDs). According to the measured temporal
response of the Au/Cu-MSM-PDs, the operation frequency could be above 10 GHz. 相似文献
107.
108.
讨论了微悬臂生化传感器在动态模式下的工作原理,针对在液体环境中阻尼增大、微悬臂共振品质因素下降的问题,设计了一个正反馈电路,使得微悬臂在液体中能够稳定在其固有频率上自激振荡.从而简便地测出微悬臂传感器在吸附分析物之后的频率变化.实验中将黄金Au溅射于微悬臂上,每次溅射的厚度为1nm,等效质量约为0.042 72 ng,溅射12次,测得去离子水中微悬臂的频率随溅射的Au质量的增加,约以-10.089 Hz/,pg的线性趋势下降,微悬臂对附加质量的检测分辨率提高了约200倍,达到1 pg. 相似文献
109.
电子接插件的快速连续电镀方法 总被引:1,自引:0,他引:1
介绍了适于电子接插件的快速连续电镀金、钯及Sn-Pb合金工艺的流程、操作要领等,对镀层的性能进行了分析比较,提出了快速电镀应解决的问题。 相似文献
110.
Soo Won Heo Eui Jin Lee Kwan Wook Song Jang Yong Lee Doo Kyung Moon 《Organic Electronics》2013,14(8):1931-1938
In this study, polymer solar cells (PSCs) doped with Au nanoparticles (Au NPs) were successfully fabricated to maximize the photon-harvesting properties on the photoactive layer. In addition, a conductivity-enhanced hybrid buffer layer was introduced to improve the photon absorption properties and effectively separate the generated charges by adding Au NPs and dimethylsulfoxide (DMSO) to the PH 500 as a buffer layer. The PSC performance was optimized with a 88% improvement over the conventional PSCs (photoactive area: 225 mm2, power conversion efficiency (PCE): 3.2%) by the introduction to the buffer layer of Au NPs and DMSO at 10 wt% and 1.0 wt%, respectively, and with 15 wt% Au NP doping in the photoactive layer. The internal resistance was decreased due to the increased photocurrent caused by the localized surface plasmon resonance (LSPR) effect of the Au NPs in the photoactive layer and by the improvement of carrier mobility induced by the DMSO doping of the buffer layer. As a result, the series resistance (RS) deceased from 42.3 to 19.7 Ω cm2 while the shunt resistance (RSH) increased from 339 to 487 Ω cm2. 相似文献