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31.
通过磁控溅射技术在Si(111)衬底上沉积Ga2O3/Co薄膜,然后在不同温度下氨化制得GaN纳米结构。采用X射线衍射(XRD)、傅里叶红外吸收谱(FTIR)、扫描电子显微镜(SEM)、高分辨透射电镜(HRTEM)和光致发光谱(PL)对样品的结构、形貌和光学特性进行了表征。结果显示合成的GaN纳米结构具有六方纤锌矿结构,且纳米结构的生长受温度影响很大。PL谱显示在388nm处有一强的紫外发光峰,表明其在低维激光器件方面的应用优势。同时对纳米结构的生长机制进行了简单讨论。 相似文献
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带有多层介质衬底FSS的损耗和带宽特性分析 总被引:11,自引:2,他引:11
本文简要介绍应用模匹配方法分析带有多层介质衬底的FSS频率响应技术,在此基础上研究带有多层介质衬底的平面Y形缝隙周期阵列对平面波的频率传输特性。重点讨论介质层厚度变化对FSS传输损耗及带宽的影响。 相似文献
35.
A procedure for producing arrays of self-aligned carbon nanotubes (CNTs) using standard chemical vapor deposition (CVD) is
reported. Using UV photolithography, silicon substrates are patterned with a thin layer of thermally evaporated iron as a
CNT catalyst. The CVD synthesis was carried out over a small temperature range (700°C–800°C) using acetylene and methane gasses,
producing aligned CNT towers. Scanning electron microscopy (SEM) analysis shows a relationship between CNT tower height and
synthesis time. Additionally, results show that impurity particles dramatically effect CNT tower growth. These results indicate
that aligned CNTs can be produced in a desired pattern with height control. 相似文献
36.
Kwang-Ting Liu 《中国化学会会志》1995,42(4):607-615
New YBnX scales of solvent ionizing power are developed and considered superior to Yx scales for benzylic bromides, chlorides, p-nitrobenzoates and tosylates in Grunwald-Winstein type correlation analysis of solvolytic reactivities. The YBnX values, with addition and revision, are summarized. Evidence for nucleophilic solvent intervention in the solvolysis transition state for secondary and tertiary benzylic substrates is given. The advantages of employing this tool to understand solvolysis mechanisms are discussed. 相似文献
37.
IC封装载板的新型表面涂饰层——ENEPIG 总被引:1,自引:0,他引:1
文章介绍一种新型的化学镀镍化学镀钯与浸金表面涂饰层,克服了化学镀镍浸金涂层的缺点,更加适合于IC封装载板上应用。 相似文献
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Core-level electronic properties of nanostructured NiO coatings 总被引:1,自引:0,他引:1
Nanostructured NiO films with different thicknesses were grown on nanoporous alumina membrane substrates by reactive evaporation of Ni in an oxygen atmosphere. The reactive deposition process was assisted by a low energy oxygen ion-beam in order to increase the NiO input into the pores. Surface morphology and structure of the films were analyzed by SEM and XPS. SEM observations reveal a well adhered film of NiO on the substrate. This film appears to be uniform and presents a rather irregular nanostructured morphology, built of NiO clusters with sizes ranging between 5 and 30 nm. The core-level electronic properties of this nanostructured NiO film result to be similar to those of an ultrathin film about one monolayer thick. This behaviour can be explained by the large surface to volume ratio of both systems. 相似文献
40.
Valerio Zardetto Thomas M. Brown Andrea Reale Aldo Di Carlo 《Journal of Polymer Science.Polymer Physics》2011,49(9):638-648
Designing and developing flexible electronics requires a thorough investigation of the substrates available for the fabrication of devices. Here, we present a practical study on a variety of significant substrates: polyethylene terephthalate (PET), its heat‐stabilized (HS) derivative, HS‐PET, and polyethylene naphthalate (PEN) plastic insulating films; indium tin oxide (ITO)‐coated ITO/PEN and ITO/PET transparent conducting films; rigid ITO/glass and FTO/glass substrates; stainless steel and titanium foils. We put the substrates through a range of tests these actually undergo during device fabrication to determine their optical, mechanical flexibility (under different types of tensile and compressive stress bending with and without a PEDOT:PSS conducting polymer layer), solvent resistance, stability to temperature treatment (conductivity and deformation), and to UV irradiation. We highlight issues and propose solutions to improve substrate response. The results and thresholds extracted reveal limitations and windows of opportunity useful for the designer of flexible optoelectronics in determining manufacturing processes and the final applications under everyday operation. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献