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131.
Solar-blind ultraviolet (UV) band-pass filter has significant value in many scientific, commercial, and military appli- cations, in which the detection of weak UV signal against a strong background of solar radiation is required. In this work, a solar-blind filter is designed based on the concept of "transparent metal". The filter consisting of Al/SiO2 multilayers could exhibit a high transmission in the solar-blind wavelength region and a wide stopband extending from near-ultraviolet to infrared wavelength range. The central wavelength, bandwidth, Q factor, and rejection ratio of the passband are numerically studied as a function of individual layer thickness and multilayer period. 相似文献
132.
Wen‐Bin Li Xiao‐Yue Yang Jing‐Tao Zhu Yu‐Chun Tu Bao‐Zhong Mu Hai‐Sheng Yu Xiang‐Jun Wei Yu‐Ying Huang Zhan‐Shan Wang 《Journal of synchrotron radiation》2014,21(3):561-567
A novel correction method for self‐absorption effects is proposed for extended X‐ray absorption fine structure (EXAFS) detected in the fluorescence mode on multilayer samples. The effects of refraction and multiple reflection at the interfaces are fully considered in this correction method. The correction is performed in k‐space before any further data analysis, and it can be applied to single‐layer or multilayer samples with flat surfaces and without thickness limit when the model parameters for the samples are known. The validity of this method is verified by the fluorescence EXAFS data collected for a Cr/C multilayer sample measured at different experimental geometries. 相似文献
133.
以氧化铝纳米孔为模板,采用直流电化学沉积的方法制备了Cd_(0.96)Zn_(0.04)S/Cd_(0.97)Mn_(0.03)S/Cd_(0.96)Zn_(0.04)S量子阱纳米线阵列,并系统研究了该纳米线阵列在不同温度和不同磁场下的电学输运特性.随着外磁场的变化,样品表现出共振传输特性.通过量子阱理论对实验现象进行了分析,直接得到了稀磁层Cd_(0.97)Mn_(0.03)S中s-d交换作用常数N_0α的定量结果.研究发现该交换作用常数随温度具有e~(-1/T)的变化趋势. 相似文献
134.
在纳米印章技术中,为克服电子束刻蚀制备50nm以下线条的技术难点,利用等离子增强化学 气相沉积技术制备了a-Si/SiNx多层膜,再利用选择性湿法腐蚀或干法腐蚀在横 截面上制备出浮雕型一维纳米级模板. 多层膜子层之间界面清晰陡峭,可以在纳米量级对子 层厚度进行控制,得到了侧壁在纳米尺度上平滑的模板. 通过控制多层膜子层的生长时间, 制备出线条宽度和槽状宽度均为20nm的等间距模板,品质优于电子束刻蚀技术制备的模板.
关键词:
纳米印章模板
多层膜生长技术 相似文献
135.
We report domain reversal behavior in perpendicular ferromagnetic nanothin films investigated by means of a novel magneto-optical microscope magnetometer, capable of grabbing domain reversal patterns in real time under an applied field as well as simultaneous measurements of 8000 local hysteresis loops with 400-nm special resolution. Three contrasting domain reversal behaviors are found to exist: wall-motion dominant, dendritic-growth dominant, and nucleation dominant reversal. Quantitative analysis reveals that the contrasting reversal behavior is mainly caused by a sensitive change in wall-motion speed and that the reversal ratio of wall-motion speed over nucleation rate is a governing parameter for the contrasting domain reversal dynamics. The activation volumes of the wall-motion and nucleation processes are found generally unequal, and the inequality is closely related with the domain dynamics. The domain reversal pattern is truly coincident with submicron-scale local coercivity variation and local switching time of domain evolution is exponentially dependent on local coercivity governed by a thermal activation relaxation process. The observed domain reversal behavior could be well predicted by a Monte Carlo simulation of a micromagnetic model based on the uniaxial magnetic anisotropy of nanothin films. 相似文献
136.
Bing Shi Jon M. Hiller Yuzi Liu Chian Liu Jun Qian Lisa Gades Michael J. Wieczorek Albert T. Marander Jorg Maser Lahsen Assoufid 《Journal of synchrotron radiation》2012,19(3):425-427
X‐ray optics called multilayer Laue lenses (MLLs) provide a promising path to focusing hard X‐rays with high focusing efficiency at a resolution between 5 nm and 20 nm. MLLs consist of thousands of depth‐graded thin layers. The thickness of each layer obeys the linear zone plate law. X‐ray beamline tests have been performed on magnetron sputter‐deposited WSi2/Si MLLs at the Advanced Photon Source/Center for Nanoscale Materials 26‐ID nanoprobe beamline. However, it is still very challenging to accurately grow each layer at the designed thickness during deposition; errors introduced during thickness measurements of thousands of layers lead to inaccurate MLL structures. Here, a new metrology approach that can accurately measure thickness by introducing regular marks on the cross section of thousands of layers using a focused ion beam is reported. This new measurement method is compared with a previous method. More accurate results are obtained using the new measurement approach. 相似文献
137.
The X‐ray optics group at the Swiss Light Source in co‐operation with RIT (Rigaku Innovative Technologies) have investigated seven different multilayer samples. The goal was to find an ideal multilayer structure for the energy range between 6 keV and 20 keV in terms of energy resolution and reflectivity. Such multilayer structures deposited on substrates can be used as X‐ray monochromators or reflecting synchrotron mirrors. The measured reflectivities agree with the simulated ones. They cover a reflectivity range from 45% to 80% for energies between 6 keV and 10 keV, and 80% to 90% for energies between 10 keV and 20 keV. The experimentally measured energy resolution of the samples lies between 0.3% and 3.5%. 相似文献
138.
139.
Nanostructural modifications in a double-graded Pt/Ni/C multi-trilayer, due to irradiation by an energetic ion-beam, have been analyzed using X-ray reflectivity (XRR), X-ray standing wave (XSW) and cross-sectional transmission electron microscopy (X-TEM) techniques. 2 MeV Au2+ ions were rastered on Pt/Ni/C multi-trilayer samples producing a uniformly irradiated area at ion-fluences ranging from 1 × 1014 ions/cm2 to 2 × 1015 ions/cm2. Ion irradiation induced modifications of microstructural parameters, e.g., layer thicknesses and electron densities of individual layers and interface roughnesses have been obtained from XRR analysis. Pt- and Ni-fluorescence yield from the as-deposited sample under the XSW condition show the distinct existence of Pt and Ni layers. The almost indistinguishable Pt- and Ni-fluorescence data over the first order Bragg peak from the sample irradiated at the highest ion-fluence, suggest complete mixing of Pt and Ni. Strong mixing between Pt and Ni in the ion irradiated samples is also corroborated by XRR results. X-TEM studies reveal the individual layer structure in the as-deposited sample. This layer structure is lost in the sample irradiated at the highest ion fluence indicating a complete mixing between Pt and Ni layers and nanoscale grain growth of Pt-Ni alloys. Additionally, formation of Pt-Ni alloy nano-clusters in the C-layers is observed. The results are understood in the light of the positive heat of mixing between Pt and C, and Ni and C and the negative heat of mixing between Pt and Ni. The effect of heat of mixing becomes dominant at high fluence irradiation. 相似文献
140.
Zhanyong Wang Hongyang Zhao Qiwen Yao Jiayue Xu Hideo Kimura 《Crystal Research and Technology》2012,47(7):799-803
ZnO/Co multilayers were fabricated on silicate (100) substrate by a pulsed laser deposition method at room temperature. The x‐ray diffraction (XRD) results reveal that the as‐deposited multilayer film is composed of amorphous phase, which leads to high saturation magnetization and low coercivity. Higher coercivity is observed in the ZnO/Co films annealed at 390 °C due to the formation of crystalline metallic Co and semiconducting ZnO. But much higher annealing temperature leads to the oxidation of metallic Co and the reaction between Co and ZnO, which decreases the saturation magnetization and coercivity obviously. 相似文献