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排序方式: 共有311条查询结果,搜索用时 31 毫秒
1.
采用正交设计实验方法分析了SnO2、MnCO3、B i2O3和A l2O3添加量对BST/MgO系铁电移相材料微波电性能影响。实验结果表明:SnO2的引入促进样品烧结,有助于降低低频和微波损耗,但过多的加入会产生第二相,会使微波损耗上升。Mn受主取代Ti产生空穴等缺陷,不利于微波损耗的降低,而等价取代类似SnO2的情况,有助于降低微波损耗,但过多的加入会产生第二相,也会使微波损耗上升。B i2O3对材料微波电性能有显著的影响,从离子半径匹配角度,B i2O3一般出现在晶粒间,形成玻璃相,一方面促进烧结,使致密化提高,低频损耗变小;另一方面低熔点的玻璃相引起微波损耗急剧上升。A l2O3对材料电性能影响不显著。 相似文献
2.
3.
低温烧结Dy-B-Si-O系玻璃介质掺杂Ba_(0.6)Sr_(0.4)TiO_3陶瓷 总被引:1,自引:1,他引:0
采用溶胶-凝胶法制备了Dy-B-Si-O系玻璃介质掺杂Ba0.6Sr0.4TiO3(BST)陶瓷粉体,并烧结成瓷。探讨了玻璃介质对BST陶瓷密度、烧结温度和介电性能的影响,利用扫描电子显微镜(SEM)、自动元件分析仪测试了BST陶瓷的显微结构和介电性能。研究结果表明,添加Dy-B-Si-O系玻璃介质降低了陶瓷烧结温度,提高了陶瓷致密度;随着Dy-B-Si-O系玻璃介质中Dy2O3组分含量的增加,介电常数增大;介电损耗先增大后减小,介电损耗最小值约为0.01,可满足在电压可调电容器上的使用要求。 相似文献
4.
D. Y. Wang Y. Wang J. Y. Dai H. L. W. Chan C. L. Choy 《Journal of Electroceramics》2006,16(4):587-591
Heteroepitaxial Ba0.7Sr0.3TiO3 thin films were grown on (LaAlO3)0.3(Sr2AlTaO6)0.35 (001) (LSAT) and SrTiO3 (001) (STO) single crystal substrates using pulsed laser deposition (PLD). X-ray diffraction characterization revealed a
good crystallinity and a pure perovskite structure for films grown on both LSAT and STO substrates. The in-plane ferroelectric
and dielectric properties of the films were studied using interdigital electrodes (IDE). The film grown on LSAT substrate
exhibited an enhanced in-plane ferroelectricity, including a well-defined P-E hysteresis loop with the remnant polarization
P
r
= 10.5 μC/cm2 and a butterfly-shaped C-V curve. Nevertheless, only a slim hysteresis loop was observed in the film grown on STO substrate. Curie temperature T
c
of the film grown on LSAT substrate was found to be ∼105∘C, which is nearly 70∘C higher than that of the bulk Ba0.7Sr0.3TiO3 ceramics. T
c
of the film grown on STO substrate has almost no change compared to the bulk Ba0.7Sr0.3TiO3 ceramics. The dielectric tunabilities were found to be 64% and 52% at 1 MHz for the films grown on LSAT and STO substrates,
respectively. 相似文献
5.
6.
改进的Sol-gel法制备Ba0.6 Sr0.4 TiO3厚膜 总被引:1,自引:1,他引:1
采用Sol-gel法在Pt/Ti/SiO2/Si和Al2O3基片上制备厚度为2~14μm的Ba0.6Sr0.4TiO3(BST)铁电厚膜材料.经高能球磨细化和表面改性后的BST陶瓷纳米粉体分散到BST溶胶中,通过甩胶法,形成0-3型BST厚膜材料.XRD图谱显示,BST呈现纯钙钛矿相结构;SEM照片显示,BST厚膜均匀致密、无裂纹;介电性能测试结果表明,当测试频率为1kHz,温度为25℃时,介电常数为620,介电损耗为0.6. 相似文献
7.
8.
采用新型的Sol-gel工艺制备了Ba0.6Sr0.4TiO3(BST)超细粉体,将BST粉体进行压制和烧结,获得了晶粒尺寸在1μm以内的BST陶瓷块体.观察了BST陶瓷块体的结晶情况并测定了其电学性能.在Sol-gel工艺中,加入了有机大分子量聚乙烯吡咯烷酮(polyvinyl pyrrolidone,PVP)制备BST前驱体.实验结果表明:PVP的加入可有效增加前驱体的稳定性和分散性,降低BST陶瓷的预烧温度约250℃,并在1200℃获得晶粒细小、致密的BST陶瓷.BST陶瓷,显示弥散相变特征. 相似文献
9.
We report on the synthesis, characterization and optical properties of barium strontium titanate (BST) quasi photonic crystals (PCs) through a sol–gel technique with the porous alumina template (PAT). The structure, morphology and pore-size distribution of the samples were characterized by SEM, XRD and EDS, The Ba0.6Sr0.4TiO3 PCs of crystalline cubic phase with uniform pore size and ordered arrange were successfully synthesized. The obtained quasi BST PCs not only show that the nanostructure has spatially periodical orderly arrangement, but also exhibit good optical transmittance properties. The advantage of this sol–gel technique with PAT to fabricate ferroelectric (FE) nanopore arrays lies in its low cost and simplicity. This study opens a pathway for the effective fabrication and studies of FE nanopore arrays in uniquely large area. 相似文献
10.
《Journal of the European Ceramic Society》2014,34(3):687-694
The influence of 30 GHz microwave sintering compared to conventional sintering has been investigated on polycrystalline Ba0.6Sr0.4TiO3 (BST60) thick films with respect to an application as tunable dielectrics. The BST thick films were prepared as metal–insulator–metal (MIM) capacitors on alumina substrates. The average grain size (440 nm) and the porosity (approx. 30%) of the sintered films are only little affected by the sintering method. However, permittivity, dielectric loss and tunability have been influenced substantially. The dielectric improvement by microwave sintering is interpreted in terms of an increased crystal quality (ξS) and/or a decrease of defect concentrations. It is assumed that microwave sintering preferably heats up parts of the film where an increased defect density exists and therefore causes a selective heating process. This may heal up charged defects, inhomogeneities, and structural defects. 相似文献