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71.
72.
M. Fukuyama 《Journal of statistical physics》2000,98(5-6):1049-1061
Georgii's theorem ensures that, restricted to two-dimensional planes, a single ocean (i.e., infinite connected component) of a ground state and islands (i.e., finite connected components) are observed in lattice spin systems at sufficiently low temperature. This paper extends his results for higher dimensional hyperplanes. Our proof is mainly based on a kind of Peierls argument and is different from Georgii's, which relies on the percolation method. 相似文献
73.
74.
75.
Megumi Kubo Takashi Kikukawa Seiji Miyauchi Akiteru Seki Masakatsu Kamiya Tomoyasu Aizawa Keiichi Kawano Naoki Kamo Makoto Demura 《Photochemistry and photobiology》2009,85(2):547-555
Halorhodopsin (HR) acts as a light‐driven chloride pump which transports a chloride ion from the extracellular (EC) to the cytoplasmic space during a photocycle reaction that includes some photointermediates initiated by illumination. To understand the chloride uptake mechanisms, we focused on a basic residue Arg123 of HR from Natronomonas pharaonis (NpHR), which is the only basic residue located in the EC half ion channel. By the measurements of the visible absorption spectra in the dark and the light‐induced inward current through the membrane, it was shown that the chloride binding and transport ability of NpHR completely disappeared by the change of arginine to glutamine. From flashphotolysis analysis, the photocycle of R123Q differed from that of wildtype NpHR completely. The response of the R123H mutant depended on pH. These facts imply that the positive charge at position 123 is essential for chloride binding in the ground state and for the chloride uptake under illumination. On the basis of the molecular structures of HR and the anion‐transportable mutants of bacteriorhodopsin, the effects of the positive charge and the conformational change of the Arg123 side chain as well as the chloride‐pumping mechanism are discussed. 相似文献
76.
Development of sulfide glass-ceramic electrolytes for all-solid-state lithium rechargeable batteries
Akitoshi Hayashi Keiichi Minami Masahiro Tatsumisago 《Journal of Solid State Electrochemistry》2010,14(10):1761-1767
Development of Li2S–P2S5-based glass-ceramic electrolytes is reviewed. Superionic crystals of Li7P3S11 and Li3.25P0.95S4 were precipitated from the Li2S–P2S5 glasses at the selected compositions. These high temperature or metastable phases enhanced conductivity of glass ceramics
up to over 10−3 S cm−1 at room temperature. The original (or mother) glass electrolytes itself showed somewhat lower conductivity of 10−4 S cm−1 and have important role as a precursor for obtaining the superionic crystals, which were not synthesized by a conventional
solid-state reaction. The substitution of P2O5 for P2S5 at the composition 70Li2S·30P2S5 (mol%) improved both conductivity and electrochemical stability of glass-ceramic electrolytes. The all-solid-state In/LiCoO2 cell using the 70Li2S·27P2S5·3P2O5 (mol%) glass-ceramic electrolyte showed initial capacity of 105 mAh g−1 (gram of LiCoO2) at the current density of 0.13 mA cm−2 and exhibited higher electrochemical performance than that using the 70Li2S·30P2S5 glass-ceramic electrolyte. 相似文献
77.
78.
Thummaruk Suksrichavalit Keiichi Yoshimatsu Virapong Prachayasittikul Leif Bülow Lei Ye 《Journal of chromatography. A》2010,1217(23):3635-3641
In this paper, we present a new modular approach to immobilize boronic acid ligands that can offer effective separation of glycoproteins. A new “clickable” boronic acid ligand was synthesized by introducing a terminal acetylene group into commercially available 3-aminophenyl boronic acid. The clickable ligand, 3-(prop-2-ynyloxycarbonylamino)phenylboronic acid (2) could be easily coupled to azide-functionalized hydrophilic Sepharose using Cu(I)-catalyzed 1,3-dipolar cycloaddition reaction under mild condition. Compared to other boronic acid affinity gels, the new affinity gel displayed superior effectiveness in separating model glycoproteins (ovalbumin and RNase B) from closely related bovine serum albumin and RNase A in the presence of crude Escherichia coli proteins. Because of the simplicity of the immobilization through “click chemistry”, the new ligand 2 is expected to not only offer improved glycoprotein separation in other formats, but also act as a useful building block to develop new chemical sensors for analysis of other glycan compounds. 相似文献
79.
Masazumi Ishiguro Kensuke Harada Keiichi Tanaka Takehiko Tanaka 《Journal of Molecular Spectroscopy》1996,180(2)
Rotational transitions of fluoroacetylene in the ν1(CH stretch) vibrational state have been observed by the laser–microwave double resonance technique using a color center laser as a radiation source in the 3 μm region. The rotational constant and centrifugal distortion constant in the ν1state were determined to be 9684.310(16) MHz and 2.68(62) kHz, respectively, where the uncertainties given in parentheses correspond to 2.5 standard deviations. 相似文献
80.
Bromide and iodide ions were determined simultaneously by capillary isotachophoresis using an aqueous electrolyte system; the separation principle was based on the ion-pairing equilibria between tetradecyldimethylbenzylammonium ion and these anions in the leading electrolyte. The interaction between iodide ion and tetradecyldimethylbenzylammonium ion was stronger than that for bromide ion. Thus complete separation of bromide and iodide ions could be obtained by using a leading electrolyte containing 1.5 mM tetradecyldimethylbenzylammonium ion. The pH of the leading electrolyte was adjusted to 5.0. The relative standard deviations of the zone length for bromide and iodide ions were 1.1 and 1.2%, respectively, when mixture of 3.0 mM of these ions was analysed. A 150-μl volume could be injected for the simultaneous determination of low concentrations of bromide and iodide ions. 相似文献