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11.
《Surface and interface analysis : SIA》2006,38(9):1257-1265
Four vanadium oxide layers on mineral TiO2(001)‐anatase supports with different thickness (3–33 Å) were prepared with reactive d.c. magnetron sputtering and were extensively studied with photoelectron spectroscopy. Al Kα radiation and 150 eV synchrotron radiation were used as excitation sources. The evolution of the 2p, 3s and 3p core level line shapes of V and Ti as a function of the vanadium oxide thickness was studied, as well as the O1s and O2s core lines and the valence band. All the V2p spectra of the deposited vanadium oxide layers consist of at least 60% V5+, the rest being V4+. The V3p region is complicated by multiplet splitting, which prevents the determination of the vanadium oxidation state. The V3p multiplet splitting is different for the two excitation energies. No reduction of the titania support surface due to the vanadium oxide deposition was observed. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
12.
《Surface and interface analysis : SIA》2006,38(10):1348-1356
We report changes in electron effective attenuation lengths (EALs) resulting from use of transport mean free paths (TMFPs) obtained from the Dirac–Hartree–Fock (DHF) potential instead of the Thomas–Fermi–Dirac (TFD) potential in an algorithm used in the National Institute of Standards and Technology (NIST) Electron Effective‐Attenuation‐Length Database (SRD 82). TMFPs from the former potential are believed to be more reliable than those obtained from the latter potential. We investigated changes in the EALs for selected photoelectron and Auger‐electron lines in four elemental solids (Si, Cu, Ag, and W), for Si 2p photoelectrons of varying energy in SiO2, and for photoelectrons excited by Al Kα X rays in four candidate gate‐dielectric materials (HfO2, ZrO2, HfSiO4, and ZrSiO4). For each material, we computed the change in the average EAL for a range of overlayer‐film thicknesses from zero to a maximum value corresponding to attenuation of the substrate signal to 10% of its original value. This EAL change was a maximum for electrons emitted normally from the surface and decreased monotonically with increasing emission angle. The maximum EAL change varied between ?4.4% and 2.6% for the three groups of materials. We found that the maximum EAL change correlated mainly with the TMFP change. We found that TMFP changes in other solids could generally lead to maximum EAL changes between ?2.6% and 1.9% for electron energies between 500 and 2000 eV. For lower energies, the maximum EAL changes could be larger for some solids. Our revised EALs for Si 2p photoelectrons in SiO2 excited by Mg and Al Kα X rays agree within 0.5% with values reported by Seah and Spencer from a detailed analysis of SiO2 film‐thickness measurements by XPS and other techniques. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
13.
14.
平朔气煤的煤岩显微组分结构研究 总被引:4,自引:3,他引:4
用显微光度计、扫描电子显微镜(SEM)、傅立叶变换红外光谱(FTIR)、X射线衍射光谱(XRD)和X光电子能谱(XPS)等测试手段研究了平朔气煤的等密度梯度离心分离(DGC)显微组分富集物的结构。结果表明,镜质组和稳定组结构相似,含氧基团基本相同,但丝质组结构则不同,它含有较多的羧基和羰基。根据实验结果讨论了三种显微组分的大分子结构,认为它们是由许多结构相似而又不相同的结构单元所构成。镜质组和稳定组的单元核心主要为脂环、缩聚芳环,环数为5—6个;丝质组单元核心主要为缩聚芳环,环数为7—8个,环缩合程度最高,芳香层片在空间排列规则,相互定向程度大。 相似文献
15.
在H6TeO6/KOH水溶液中以臭氧为氧化剂,将二价铜化合物氧化成三价铜化合物,并获得一个新的三价铜化合物Ba4K[Cu(H2TeO6)2](OH)4.6H2O;描述了碱性溶液中“Cu(Ⅲ)/Cu(Ⅲ)”循环伏安图。对铜(Ⅲ)化合物,Na4H[H2TeO6)2].17H2O以及相应的铜(Ⅱ)配合物的电子光谱和Cu2pXPS进行了研究,给出了其配位场场强参数和Cu2PXPX的电子结合能。由于价态升高 相似文献
16.
《Surface and interface analysis : SIA》2005,37(8):683-688
Heating (100) silicon at high temperature (say, higher than 850 °C) in H2, cooling to 670–700 °C in the same ambient, and quenching to room temperature in N2 results in environmentally robust, terraced 1 × 1 (100) SiH2. Evidence for this conclusion is based on angle‐resolved x‐ray photoelectron spectroscopy, atomic force microscopy, infrared absorption spectroscopy in the attenuated total reflection mode, thermal programmed desorption, and reflection high‐energy electron diffraction. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
17.
《Surface and interface analysis : SIA》2004,36(7):624-631
In this paper Al, Zn and Al–43.4Zn–1.6Si (AlZn) alloy‐coated steel have been treated with the organofunctional silane γ‐mercaptopropyltrimethoxysilane (γ‐MPS). The influence of different metal substrates on the structure and composition of the silane films was investigated with XPS and AES. The films were obtained by dipping the substrates in the silane solution followed by a blow‐dry procedure in nitrogen gas. The results show that the surface concentration of the deposited silane is independent of the metal substrate and that the thickness of the silane film is non‐uniform. The AES measurements indicate that the silane film covers the entire substrate surface and XPS analysis of the silane‐treated substrate surfaces at different take‐off angles indicates that the γ‐MPS molecule is randomly orientated. Also, the results show that the silane is well hydrolysed under the solution conditions used. Finally, in the zinc‐containing silane‐metal systems, i.e. the silane‐treated AlZn and Zn substrates, the results indicate that the γ‐MPS molecules can bond to the substrate surfaces via the thiol group of the molecule. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
18.
合成了六种轻希土硫氰酸盐与标题不饱和冠醚的新固体配合物,进行了元素分析,摩尔电导率、DTA、UV、IR和XPS等表征.对Ln(NCS)3·L和Ln(NCS)3的XPS研究中,得到它们组成原子芯能级电子(Ln3d5/2,Ols,Nls,S2p)的结合能信息;观察到除Y3d5/2外Ln3d5/2(Ln=La、Ce、Pr、Nd、和Sm)的伴峰结构,Ln3d5/2结合能与原子序数呈线性关系,并推断类似化合物Pm3d5/2结合能在1035eV附近. 相似文献
19.
JD树脂刻蚀及涂层的XPS研究 总被引:2,自引:0,他引:2
JD光学树脂表面刻蚀过程的XPS研究表明,引进树脂遥COH,C=O,C-SO3H,COOH等基因随刻蚀温度的提高或时间的延长而增加,对其相对含量进行了计算,固化后的耐磨涂层具有SiO2结构,JD板材的最佳刻蚀条件为20℃,20min。 相似文献
20.
测定了一系列氧化物的电子结合能,显示了铋系超导体与二元氧化物衬底材料的化学反应性可以用固态酸碱反应理论来描述,其反应性大小除了可以用衬底氧化物的酸碱参数估计以外,还可以用衬底氧化物氧离子的内层电子结合能估计. 相似文献