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排序方式: 共有630条查询结果,搜索用时 546 毫秒
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超分子结构水杨酸根插层水滑石的组装及结构与性能研究 总被引:26,自引:0,他引:26
以锌铝水滑石ZnAl-CO3 LDHs为前体(主体),以乙二醇为分散介质,用离子 交换法组装了水杨酸根(客体)插层水滑石ZnAl-[o-HO(C6H4)COO]LDHs,并用XRD ,FT-IR,TG-DTA等手段对样品进行了表征。结果表明,能过控制离子交换条件, 水杨酸根阴离子可取代锌铝水滑石前体层间的CO3^2-离子,组装得到晶体结构良好 的水杨酸根插层水滑石。通过研究发现,主体水滑石层板与客体以静电力和氢键相 互作用,得到的超分子结构材料紫外阻隔作用增强并具有较好的稳定性,从而成为 一种集屏蔽和吸收双重功能的新型无机-有机得合紫外阻隔材料。 相似文献
24.
The experimental one-, three-, and five-quasiparticle bands in ~(177)Lu are analyzed by the particle-number conserving (PNC) method for treating the cranked shell model with pairing interaction, in which the blocking effects are taken into account exactly. The experimental moments of inertia are reproduced very well by PNC calculations with us free parameter. 相似文献
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Festag G Steinbrück A Wolff A Csaki A Möller R Fritzsche W 《Journal of fluorescence》2005,15(2):161-170
DNA microarrays are promising tools for fast and highly parallel DNA detection by means of fluorescence or gold nanoparticle labeling. However, substrate modification with silanes (as a prerequisite for capture DNA binding) often leads to inhomogeneous surfaces and/or nonspecific binding of the labeled DNA. We examined both different substrate cleaning and activating protocols and also different blocking strategies for optimizing the procedures, especially those for nanoparticle labeling. Contact angle measurements as well as fluorescence microscopy, atomic force microscopy (AFM), and a flatbed scanner were used to analyze the multiple-step process. Although the examined different cleaning and activating protocols resulted in considerably different contact angles, meaning different substrate wettability, silanization led to similar hydrophobic surfaces which could be revealed as smooth surfaces of about 2–4 nm roughness. The two examined silanes (3-glycidoxypropyltrimethoxysilane (GOPS) and 3-aminopropyltriethoxysilane (APTES)) differed in their DNA binding homogeneity, maximum signal intensities, and sensitivity. Nonspecific gold binding on APTES/PDC surfaces could be blocked by treatment in 3% bovine serum albumin (BSA). 相似文献
27.
Olga Polverino 《Designs, Codes and Cryptography》2000,20(3):319-324
In this paper we show that a small minimalblocking set in PG(2,p3), with p 7,is of Rédei type. 相似文献
28.
Sachin Joshi Sagnik Dey Michelle Chaumont Alan Campion Sanjay K. Banerjee 《Journal of Electronic Materials》2007,36(6):641-647
We demonstrate ultra-thin (<150 nm) Si1−x
Ge
x
dislocation blocking layers on Si substrates used for the fabrication of tensile-strained Si N channel metal oxide semiconductor
(NMOS) and Ge P channel metal oxide semiconductor (PMOS) devices. These layers were grown using ultra high vacuum chemical
vapor deposition (UHVCVD). The Ge mole fraction was varied in rapid, but distinct steps during the epitaxial layer growth.
This results in several Si1−x
Ge
x
interfaces in the epitaxially grown material with significant strain fields at these interfaces. The strain fields enable
a dislocation blocking mechanism at the Si1−x
Ge
x
interfaces on which we were able to deposit very smooth, atomically flat, tensile-strained Si and relaxed Ge layers for the
fabrication of high mobility N and P channel metal oxide semiconductor (MOS) devices, respectively. Both N and P channel metal
oxide semiconductor field effect transister (MOSFETs) were successfully fabricated using high-k dielectric and metal gates
on these layers, demonstrating that this technique of using ultra-thin dislocation blocking layers might be ideal for incorporating
high mobility channel materials in a conventional CMOS process. 相似文献
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《Journal of Polymer Science.Polymer Physics》2018,56(16):1164-1173
Electro‐active polymers (EAPs) such as P(VDF‐TrFE‐CTFE) are greatly promising in the field of flexible sensors and actuators, but their low dielectric strength driven by ionic conductivity is a main concern for achieving high electrostrictive performance. It is well known that there is a quadratic dependence of the strain response and mechanical energy density on the applied electric field. This dependence highlights the importance of improving the electrical breakdown EAPs while reducing the dielectric losses. This article demonstrates that it is possible to dramatically increase the electrical breakdown and decrease the dielectric losses by controlling processing parameters of the polymer synthesis and fabrication procedure. As a result, an enhancement of around 70% is achieved in both the strain and blocking force. The effects on the dielectric losses of the polymer crystallinity, molecular weight, solvent purity, and crystallization temperature are also investigated. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1164–1173 相似文献