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131.
Eann A. Patterson Erwin Hack Philippe Brailly Richard L. Burguete Qasim Saleem Thorsten Siebert Rachel A. Tomlinson Maurice P. Whelan 《Optics and Lasers in Engineering》2007,45(5):550
The design and testing of a reference material for the calibration of optical systems for strain measurement is described, together with the design and testing of a standardized test material that allows the evaluation and assessment of fitness for purpose of the most sophisticated optical system for strain measurement. A classification system for the steps in the measurement process is also proposed and allows the development of a unified approach to diagnostic testing of components or sub-systems in an optical system for strain measurement based on any optical technique. The results described arise from a European study known as SPOTS whose objectives were to begin to fill the gap caused by a lack of standards. 相似文献
132.
Thorsten Grb Gertraud Geiseler Klaus Harms Andreas Greiner Kurt Dehnicke 《无机化学与普通化学杂志》2002,628(1):217-221
Phosphoraneiminato Complexes of Zirconium: Crystal Structures of [ZrCl3(NPPh3)(HNPPh3)2] and [ZrCl2(NPPh3)2(HNPPh3)2] The phosphoraneiminato complexes [ZrCl3(NPPh3)(HNPPh3)2] ( 1 ) and [ZrCl2(NPPh3)2(HNPPh3)2] ( 2 ) have been obtained by reaction of [ZrCl4(THF)2] with [CsNPPh3]4 in THF solution to give colourless moisture sensitive crystals which are characterized by X‐ray structure determinations. [ZrCl3(NPPh3)(HNPPh3)2] ( 1 ): Space group P 1, Z = 2, lattice dimensions at 193 K: a = 1209.4(2); b = 1480.8(2); c = 1814.2(2) pm; α = 71.203(13)°, β = 71.216(13)°, γ = 74.401(13)°; R = 0.0476. The zirconium atom of 1 is oktahedrally coordinated by the three chlorine atoms in meridional arrangement and by the three nitrogen atoms of the (NPPh3–) ligand and of the two phosphane imine molecules HNPPh3. The ZrN bond distance of the (NPPh3–) group (193.5 pm) corresponds with a double bond. [ZrCl2(NPPh3)2(HNPPh3)2] ( 2 ): Space group P 1, Z = 4, lattice dimensions at 193 K: a = 1447.6(2); b = 1925.7(2), c = 2457.0(2) pm; α = 67.317(12)°, β = 87.376(12)°, γ = 87.103(13)°; R = 0.0408. The zirconium atom in 2 is octahedrally coordinated by the two chlorine atoms in trans position, and by the nitrogen atoms of the two (NPPh3–) groups as well as by the two HNPPh3 molecules. The ZrN distance of the (NPPh3–) ligands (198.9 and 202.0 pm) suggest some π‐interaction between the zirconium and the nitrogen atoms. 相似文献
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The synthesis of two 12-nordrimanes and yahazunol was achieved via 8-oxo-12-nordrimanic acid methyl ester. The cytotoxic activity of yahazunol and seven other sesquiterpene hydroquinones and sesquiterpene quinones has been determined. 相似文献
136.
Block copolymers are well‐known for their large number of microphase morphologies on mesoscopic length scales. After a short review of the different morphologies observed in binary block copolymers and ternary triblock copolymers, the self‐assembling in blends of different block copolymers into common superlattices is discussed in detail. Besides similar morphologies known for pure triblock and diblock copolymers, the blends can also show new morphologies. Examples of such new morphologies are periodic non‐centrosymmetric lamellae and multiple gyroid interface structures. The discussion of the superlattices is primarily based on investigations by transmission electron microscopy (TEM), which are supplemented in a few cases by small angle X‐ray scattering (SAXS) or results from computer simulations. 相似文献
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139.
Jos I. Urgel Marco Di Giovannantonio Kristjan Eimre Thorsten G. Lohr Junzhi Liu Shantanu Mishra Qiang Sun Amogh Kinikar Roland Widmer Samuel Stolz Max Bommert Reinhard Berger Pascal Ruffieux Carlo A. Pignedoli Klaus Müllen Xinliang Feng Roman Fasel 《Angewandte Chemie (International ed. in English)》2020,59(32):13281-13287
Cumulene compounds are notoriously difficult to prepare and study because their reactivity increases dramatically with the increasing number of consecutive double bonds. In this respect, the emerging field of on‐surface synthesis provides exceptional opportunities because it relies on reactions on clean metal substrates under well‐controlled ultrahigh‐vacuum conditions. Here we report the on‐surface synthesis of a polymer linked by cumulene‐like bonds on a Au(111) surface via sequential thermally activated dehalogenative C?C coupling of a tribenzoazulene precursor equipped with two dibromomethylene groups. The structure and electronic properties of the resulting polymer with cumulene‐like pentagon–pentagon and heptagon–heptagon connections have been investigated by means of scanning probe microscopy and spectroscopy methods and X‐ray photoelectron spectroscopy, complemented by density functional theory calculations. Our results provide perspectives for the on‐surface synthesis of cumulene‐containing compounds, as well as protocols relevant to the stepwise fabrication of carbon–carbon bonds on surfaces. 相似文献
140.
Wissdorf W Pohler L Klee S Müller D Benter T 《Journal of the American Society for Mass Spectrometry》2012,23(2):397-406
Results obtained with two computational approaches for the simulation of ion motion at elevated pressure are compared with
experimentally derived ion current data. The computational approaches used are charged particle tracings with the software
package SIMION ver. 8 and finite element based calculations using the software package Comsol Multiphysics ver. 4.0/4.0a.
The experimental setup consisted of a tubular corona discharge ion source coupled to a cylindrical measurement chamber held
at atmospheric pressure. Generated ions are flown into the chamber at essentially subsonic laminar isothermal conditions.
In the simulations, strictly stationary conditions were assumed. The results show very good agreement between the SIMION/SDS
model and experimental data. For the Comsol model, only qualitative agreement is observed. 相似文献