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991.
Yongfei Wang Cunrui Zhang Baodong Li 《Journal of magnetism and magnetic materials》2009,321(19):3368-3372
The sol was obtained by sol-gel method. Then, the sol was dripped onto the absorbent cotton template. The gel was obtained after the evaporation of water. Strontium ferrite microtubules were prepared after carrying out calcination process at different temperatures. The phase, morphology and particle diameter and the magnetic properties of samples were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM), respectively. The effects of Fe3+/Sr2+ mole ratio and calcination temperature on the crystal structure, morphology and magnetic properties of ferrite microtubules were studied. The external diameters of obtained SrFe12O19 microtubules were found to range between 8 and 13 μm; the wall thicknesses ranged between 1 and 2 μm. When the Fe3+/Sr2+ mole ratio and the calcination temperature were 11.5 and 850 °C, respectively, the coercivity, saturation magnetization and remanent magnetization for the samples were 7115.1 Oe, 70.1 and 42.4 emu/g, respectively. The mechanism of the formation and variation in magnetic properties of the microtubules were explained. 相似文献
992.
Meixiang Wan 《Macromolecular rapid communications》2009,30(12):963-975
This feature article reviews the authors' work combined with highlighted specific aspects of polyaniline (PANI) macro/nanostructures, focusing on such issues as the following. 1) The new development of a hard‐template method. 2) Evaluation of a template‐free method in universality, controllability, and simplicity as well as the self‐assembly mechanism. 3) Multi‐functionality based on a template‐free method associated with other approaches. 4) Cooperation effect of a micelle soft‐template and molecular interactions as a new tool to complex 3D microstructures assembled from 2D or 1D nanostructures. 5) Electrical and transport properties of a single PANI nanotube, as measured by a four‐probe method. 6) Sensors guided by reversible switching wettability through a doping/de‐doping process. An outlook is also briefly given.
993.
994.
以油菜花粉为生物模板,通过温和易控的水浴-陈化法制备了纳/微米结构ZrO2中空微球.利用扫描电子显微镜(SEM)、红外光谱(FTIR)、X射线能谱(EDS)、X射线衍射(XRD)、比表面孔隙度分析、热分析等对所制备的产物和前驱体进行了表征,并对产物的吸附性能进行了初步的研究.结果表明,ZrO2中空微球的球壳由纳米粒子构筑并形成介孔结构.花粉模板前处理方式不同,其模板作用不同,可以获得两种不同球壳厚度、表面形貌和比表面积的ZrO2中空微球.其中"镂空"结构的ZrO2微球对铬黑T有良好的吸附性能.对ZrO2中空结构形成的机理进行了分析和讨论. 相似文献
995.
本文将合成的直径为10 nm的正电荷金纳米颗粒通过静电作用高密度自组装到带负电荷的长链λ-DNA分子上, 形成了高密度的具有纳米间隙的金纳米颗粒网络结构。研究了孤立的金纳米颗粒和所自组装的金纳米颗粒-DNA复合材料作为表面增强拉曼散射(SERS)基底的活性。原本对SERS信号响应较弱的10 nm直径的金纳米颗粒, 在自组装到DNA上形成具有纳米间隙的金纳米颗粒网络后, 产生了均匀、一致、强烈的SERS增强响应。我们利用用该基底对罗丹明G(R6G)、吡啶(Py)和对巯基苯胺(4-ATP)等不同类型的小分子化合物进行SERS检测的结果表明, 此方法制备SERS基底产率高、均一, 具有较好的SERS增强效果好, SERS信号稳定性和重复性相对常规孤立的金纳米颗粒SERS基底有很大提高。 相似文献
996.
Vertical-aligned Ag nanoflake arrays are fabricated on the surface of an anodic aluminum oxide (AAO) template under a hydrothermal condition for the first time. The porous surface of AAO templates and the precursor solution may play key roles in the process of fabricating Ag nanoflakes. The rim of pores can provide many active sites for nucleation and growth, and then nanoflake arrays gradually form through self-assembly of Ag on the surface of AAO membranes. The product is characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and a growth mechanism of nanoflake is deduced. This work demonstrates that it is possible to make ordered nanoarrays without dissolving templates using the hydrothermal method, and this interesting Ag nanoflake arrays may provide a wider range of nanoscale applications. 相似文献
997.
Y.‐J. Liu Z.‐Y. Zhang R. A. Dluhy Y.‐P. Zhao 《Journal of Raman spectroscopy : JRS》2010,41(10):1112-1118
Semiordered Ag nanorod arrays are fabricated by template oblique angle deposition (OAD) using regular Au nano‐post arrays with different diameters as seed patterns. The Au nano‐post arrays do not give an observable surface‐enhanced Raman scattering (SERS) activity under our detection configuration, whereas the patterned Ag nanorod arrays can produce a very strong SERS signal. These SERS intensities increase monotonically with the decrease in the diameter and separation of the Ag nanorods, which demonstrates that one can improve the SERS detection by tuning the diameter and separation of the Ag nanorods, and the template OAD method can help produce more uniform, reproducible, and sensitive Ag nanorod SERS substrates. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
998.
Summary : High-yield synthesis of gold microplates is achieved through autoreduction of hydrogen tetrachloroaureate (III) hydrate (HAuCl4 · 3H2O) in aqueous solutions of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) block copolymer (Pluronic L64, EO13PO30EO13) at ambient conditions, in the absence of added energy, reductant, or other surfactants. The formation by the amphiphilic block copolymer of lyotropic liquid crystals (e.g., ordered cylindrical/hexagonal or lamellar phases) is not required for templating the formation of such microplates. 相似文献
999.
Polyelectrolytes introduced in the aqueous subphase are shown to have a profound impact on the kinetics of polymerization of N-octadecylaniline at the air/water interface. This can be attributed to changes effected in molecular organization and reorientation behavior in the Langmuir film. The polyelectrolyte templates lead to considerable modification of the morphology of the monomer and polymer Langmuir films. Polyelectrolyte complexation is found to be an elegant and efficient methodology to achieve enhanced alignment of the polyaniline chains in the transferred Langmuir-Blodgett (Langmuir-Schafer) film. 相似文献
1000.
(C4N2H12)[Ga2F3(HPO3)2(H2PO3)] 1 is a new open-framework fluorinated gallium phosphite obtained by mild hydrothermal synthesis using piperazine as template agent and characterized by single crystal X-ray diffraction (XRD), powder XRD, infra-red spectroscopy, inductively coupled plasma, thermogravimetric and elemental analyses. The three-dimensional (3D) anionic framework of compound 1 is constructed from two distinct motifs, a 1D tancoite chain and a single 4-ring (S4R) unit, which contains four intersecting channels running throughout the structure as 8, 12-member rings channels along to the a-axis and 12-member ring channels along the b- and c-axis, respectively. The well-ordered, diprotonated piperazine cations occupy all the channels, and interact with the fluorinated gallium-phosphite framework by strong hydrogen bonds. 相似文献