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941.
Thalhammer A Mecinović J Loenarz C Tumber A Rose NR Heightman TD Schofield CJ 《Organic & biomolecular chemistry》2011,9(1):127-135
Based on structural analysis of the human 2-oxoglutarate (2OG) dependent JMJD2 histone N(ε)-methyl lysyl demethylase family, 3-substituted pyridine 2,4-dicarboxylic acids were identified as potential inhibitors with possible selectivity over other human 2OG oxygenases. Microwave-assisted palladium-catalysed cross coupling methodology was developed to install a diverse set of substituents on the sterically demanding C-3 position of a pyridine 2,4-dicarboxylate scaffold. The subsequently prepared di-acids were tested for in vitro inhibition of the histone demethylase JMJD2E and another human 2OG oxygenase, prolyl-hydroxylase domain isoform 2 (PHD2, EGLN1). A subset of substitution patterns yielded inhibitors with selectivity for JMJD2E over PHD2, demonstrating that structure-based inhibitor design can enable selective inhibition of histone demethylases over related human 2OG oxygenases. 相似文献
942.
Eryazici I Farha OK Compton OC Stern C Hupp JT Nguyen ST 《Dalton transactions (Cambridge, England : 2003)》2011,40(36):9189-9193
A new class of infinite coordination polymers (CP) was synthesized using a tetrahedral tetrakis[4-(4'-phenyl-2,2':6',2'-terpyridine)phenyl]methane ligand as an organic node to direct the three-dimensional growth of the network and M(II) (M = Zn, Fe, Ni, and Ru) ions as inorganic linkers, an approach that is the opposite of the metal-as-a-node strategy used in the construction of metal-organic frameworks (MOFs). The unusual rod-like morphology of the resulting microporous materials can be tuned via solvents and reaction conditions. The covalent entrapment of a [Ru(tpy)(2)](2+) moiety in the skeleton of the 3D-network enables the Ru-CP to exhibit room-temperature luminescence. 相似文献
943.
Tao H Jin Q Koo DI Liao X Englund NP Wang Y Ramamurthy A Schultz PG Dorsch M Kelleher J Wu X 《Chemistry & biology》2011,18(4):432-437
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944.
Kornau KM Rickard MA Mathew NA Pakoulev AV Wright JC 《The journal of physical chemistry. A》2011,115(16):4054-4062
Multiresonant four wave mixing has been used to measure the coherent multidimensional spectroscopy (CMDS) of representative aromatic ring modes using pyridine as a model system. This work identifies the cross-peaks that appear between several modes and measures their coherent and incoherent dynamics. The work also explores the consequences of using multiresonant CMDS for molecules with transition moments that are typical of most vibrational modes. Typically, CMDS experiments rely on using transitions with exceptionally large transition moments. To observe cross-peaks, the pyridine concentration was raised until absorption effects became very important. These effects interfere with the parametric CMDS coherence pathways, but they do not make important contributions to the nonparametric pathways. 相似文献
945.
Enzymes are the prime protagonists in the chemistry of living organisms. As such, chemists and biologists have long been fascinated by the array of highly selective transformations possible under biological conditions that are facilitated by enzyme-catalyzed reactions. Moreover, enzymes are involved in replicating, repairing and transmitting information in a highly selective and organized fashion through detection and signal amplification cascades. Indeed, because of their selectivity and potential for use outside of biological systems, enzymes have found immense utility in various biochemical assays and are increasingly finding applications in the preparation of small molecules. By contrast, the use of enzymatic reactions to prepare and build supramolecular and nanoscale materials is relatively rare. In this article, we seek to highlight efforts over the past 10 years at taking advantage of enzymatic reactions to assemble and manipulate complex soft, organic materials on the nanoscale. It is tantalizing to think of these processes as mimics of natural systems where enzymes are used in the assembly and transformation of the most complex nanomaterials known, for example, virus capsid assemblies and the myriad array of nanoscale biomolecular machinery. 相似文献
946.
The thermal processes during progressive calcination of sulfur-rich calcareous oil shales were analyzed using FT-IR spectroscopy
and applying curve-fitting technique. The spectroscopic analysis is advantageous in the analysis of amorphous and short-range
ordered thermal phases lacking of XRD peaks. The raw calcareous oil shales are composed of organic matter, kaolinite, smectite,
calcite, and apatite (francolite). The principal thermal phases are metakaolinite, meta-smectite, free lime, anhydrite, gehlenite,
and ellestadite. The thermal reactions observed with increase temperatures includes decomposition of organic matter followed
by release of sulfur gas; dehydroxylation of kaolinite; and smectite at 500–600 °C; and thermal transformation to metakaolinite
and meta-smectite; decarbonation of microcrystalline calcite to free lime at 600 °C; reaction of the sulfur gas with the free
lime; formation of anhydrite at 600 °C; reaction of apatite and formation of ellestadite at 800 °C; reaction of the metakaolinite;
the meta-smectite with the free lime; formation of gehlenite at 900 °C. Owingto the sulfatization process, a great part of
the sulfur content of the raw oil shales is retained in the calcined ashes and the release of sulfur gas to the atmosphere
decreases. Thus, the combustion of calcareous oil shales for energy source has less pollution effect than that of the clayey
oil shales. FT-IR spectroscopy and spectral analysis seems to be useful methods for phase analysis of oil shales in combustion
industry. 相似文献
947.
Camacho-Alanis F Castaneda H Zangari G Swami NS 《Langmuir : the ACS journal of surfaces and colloids》2011,27(18):11273-11277
Modifications to the space charge region of p+ and p-GaAs due to surface charge modulation by the pH-induced deprotonation of bound carboxylic acid terminal monolayers were studied by electrochemical impedance spectroscopy and correlated to flat-band potential measurements from Mott-Schottky plots. We infer that the negative surface dipole formed on GaAs due to monolayer deprotonation causes an enhancement of the downward interfacial band bending. The space charge layer modifications were correlated to intermolecular electrostatic interactions and semiconductor depletion characteristics. 相似文献
948.
Leal C Ewert KK Shirazi RS Bouxsein NF Safinya CR 《Langmuir : the ACS journal of surfaces and colloids》2011,27(12):7691-7697
The self-assembly of a custom-synthesized pentavalent cationic lipid (MVL5) and glycerol monooleate (GMO) with small interfering RNA (siRNA) results in the formation of a double-gyroid bicontinuous inverted cubic phase with colocalized lipid/siRNA domains as shown by synchrotron X-ray scattering and fluorescence microscopy. The high charge density (due to MVL5) and positive Gaussian modulus of the GMO-containing membranes confer optimal electrostatic and elastic properties for endosomal escape, enabling efficient siRNA delivery and effective, specific gene silencing. 相似文献
949.
Betul?Akkopru?Akgun Anthony?W.?Wren Caner?Durucan Mark?R.?Towler Nathan?P.?MellottEmail author 《Journal of Sol-Gel Science and Technology》2011,59(2):228-238
Titanium dioxide (TiO2) and silver-containing TiO2 (Ag-TiO2) thin films were prepared on silica pre-coated float glass substrates by a sol–gel spin coating method. The bactericidal
activity of the films was determined against Staphylococcus epidermidis under natural and ultraviolet (UV) illumination by four complementary methods; (1) the disk diffusion assay, (2) UV-induced
bactericidal test, (3) qualitative Ag ion release in bacteria inoculated agar media and (4) surface topographical examination
by laserscan profilometry. Photocatalytic activity of the films was measured through the degradation of stearic acid under
UV, solar and visible light conditions. The chemical state and distribution of Ag nanoparticles, as well as the structure
of the TiO2 matrix, and hence the bactericidal and photocatalytic activity, is controlled by post-coating calcination treatment (100–650 °C).
Additionally, under any given illumination condition the Ag-incorporated films were found to have superior bactericidal and
photocataltyic activity performance compared to TiO2 thin films. It is shown that with optimized thin film processing parameters, both TiO2 and Ag-TiO2 thin films calcined at 450 °C were bactericidal and photocatalytically active. 相似文献
950.
Fujii Kengo Endo Nobuaki Hagen Nathan Yasugi Masaki Suyama Shiro Yamamoto Hirotsugu 《Optical Review》2022,29(5):429-439
Optical Review - We propose a method to realize video calling with an aerial display using a camera that has a direct view of the speaker's face, but which is not visible to the speaker.... 相似文献