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361.
Yu‐ichiro Matsushita Galia Madjarova José A. Flores‐Livas J. K. Dewhurst C. Felser S. Sharma E. K. U. Gross 《Annalen der Physik》2017,529(8)
We present a novel approach for designing new hard magnets by forming stacks of existing binary magnets to enhance the magneto crystalline anisotropy. This is followed by an attempt at reducing the amount of expensive metal in these stacks by replacing it with cheaper metal with similar ionic radius. This strategy is explored using examples of FePt, MnAl and MnGa. In this study a few promising materials are suggested as good candidates for hard magnets: stacked binary FePt2MnGa2 in structure where each magnetic layer is separated by two non‐magnetic layers, FePtMnGa and FePtMnAl in hexagonally distorted Heusler structures and FePt0.5Ti0.5MnAl. 相似文献
362.
Ryo Shomura Shuhei Higashibayashi Hidehiro Sakurai Yoshitaka Matsushita Akira Sato Masayoshi Higuchi 《Tetrahedron letters》2012,53(7):783-785
Enantiopure phenylazomethine cages ((S)- and (R)-PAC) were selectively obtained by one-pot dehydration of chiral (S)- and (R)-syn-tris(norborneno)benzene with p-phenylenediamine in moderate yields (56% and 50%), respectively. The structure and chirality of PACs in solution and solid state were confirmed by NMR, CD, X-ray diffraction and DFT calculations. 相似文献
363.
Ono Kiminori Watanabe Aki Dewa Kazuki Matsukawa Yoshiya Saito Yasuhiro Matsushita Yohsuke Aoki Hideyuki Fukuda Okiteru Aoki Takayuki Yamaguchi Togo 《Journal of nanoparticle research》2014,16(7):1-11
Journal of Nanoparticle Research - Dextrans are widely used as additives in food, pharmaceutical, and cosmetics because of their hydrophilicity, biocompatibility, and low toxicity. These features... 相似文献
364.
The thermal reaction of methyl 2-oxo-2H-pyran-5-carboxylates with substituted styrenes in the presence of 10% palladium on activated carbon afforded directly the corresponding methyl 4-biphenylcarboxylates in good yields. By the similar procedure, methyl 4-heteroaryl- and 4-alkyl-substituted benzoates were obtained from heteroaromatic olefins and alkenes, respectively. 相似文献
365.
R. Kadono S. Fujii A. Matsushita K. Nagamine K. Nishiyama S. Tanigawa 《Hyperfine Interactions》1994,85(1):79-84
Muonium diffusion was studied in silicon doped GaAs by means of muon spin relaxation in a longitudinal field. The muonium hopping frequencies in two samples with n-type carrier concentration of 101214 cm–3 and 8×1016 cm–3 were deduced by using the model of fluctuating effective local fields. We found that muonium diffusion is strongly influenced by the dilute Si impurity in both samples in the temperature range belowT
30K. The absence of such a behavior in compensated high-resistivity samples indicates that the presence of shallow donor levels plays a decisive role for the tunneling diffusion of muonium in semiconductors.We would like to thank Drs. N.V. Prokof'ev and R.F. Kiefl for helpful discussion.After submission of this paper it was revealed by the field dependence of the LF relaxation rate that the observed relaxation rate in GaAs:Si-B is due to spin-exchange interaction of Mu*. 相似文献
366.
Takaaki Taniguchi Hikaru Tateishi Shinnsuke Miyamoto Kazuto Hatakeyama Chikako Ogata Asami Funatsu Shinya Hayami Yuki Makinose Nobuhiro Matsushita Michio Koinuma Yasumichi Matsumoto 《Particle & Particle Systems Characterization》2013,30(12):1063-1070
Graphene oxide (GO) is an attractive freestanding support that can be decorated with ultrathin organic layers for facile and low‐cost fabrication of novel devices with controllable functional properties and microstructures. Here, it is reported that a hybrid material consisting of an ultrathin iron phthalocyanine (FePc) layer self‐assembled on reduced graphene oxide (rGO) exhibits excellent catalytic activity that is superior to that of commercial Pt/C for an oxygen reduction reaction (ORR). During solution processing, the FePc layer is first self‐organized onto GO sheets and then reduced electrochemically to form an FePc/rGO hybrid electrocatalyst. Kinetics studies reveal that the hybrid architecture affords an ultrafast ORR rate caused by a strongly dominant four‐electron process, and the durability of the catalyst shows significant improvement by forming the hybrid structure. Spectroscopic studies suggest that these advantages are afforded by synergistic effects between FePc and rGO, which are enriched by the hybrid structure and the appropriate reduction step. 相似文献
367.
Y. Satou K. Tshoo H. Bhang S. Choi J. W. Hwang T. Nakamura Y. Kondo Y. Nakayama N. Kobayashi K. N. Tanaka S. Deguchi Y. Kawada N. Tanaka T. Motobayashi H. Sakurai H. Otsu N. Aoi S. Takeuchi K. Yoneda Y. Togano M. Ishihara S. Shimoura T. Kobayashi M. Matsushita T. Honda T. Sumikama Y. Miyashita K. Yoshinaga N. A. Orr F. M. Marques J. Gibelin F. Delaunay D. Sohler T. Zheng Z. H. Li Z. X. Cao 《Few-Body Systems》2013,54(1-4):287-290
The neutron-rich oxygen isotope 23O has been investigated via proton inelastic scattering on a liquid hydrogen target at 63.5 MeV/nucleon. The invariant mass method in inverse kinematics was employed to reconstruct the energy spectrum. A sharp resonance state was observed at 42(5) keV above the neutron threshold. A comparison of the differential cross section leading to this state with a microscopic DWBA calculation allowed a J π assignment of 5/2+ for this state. 相似文献
368.
A two-phase alloy of β-Sn and Al63Cu25Fe12 quasicrystal produced by melt-spinning was annealed and aged to form various microstructures of tin in a quasicrystalline (QC) or microcrystalline (MC) matrix. The morphology and structure of the interfaces was studied by scanning and transmission electron microscopy and was related to melting and solidification behavior of tin studied by differential scanning calorimetry. In a MC matrix the tin phase occurred as nanoparticles and solidified with an undercooling of about 35°C. In a QC matrix, tin formed intergranular layers on faceted matrix grains. Tin showed multiple solidification peaks in undercooling ranging from 8°C to 43°C, indicating several distinct nucleation sites which compete with each other and are selected kinetically. The interfacial energy (depending on the structural state of the matrix) had a more dominating effect on the solidification of tin than the size, shape and the distribution of the tin particles. It was also concluded that solidification of tin is easier on quasicrystalline surfaces than on aluminum. 相似文献
369.
Masashi Harada Takahisa Suzuki Masayuki Ohya Daisuke Kawaguchi Atsushi Takano Yushu Matsushita Naoya Torikai 《Journal of Polymer Science.Polymer Physics》2005,43(12):1486-1494
Compositional profiles of bilayer films in the direction normal to the interfaces have been investigated by neutron reflectivity measurements and analyzed with mean field theory. The bilayer films were prepared with poly(4‐trimethylsilylstyrene) (PTMSS) and polyisoprene (PI), which constitute a miscible polymer pair and whose blends show phase separation at the lower critical solution temperature (LCST) by heating. Because we can accurately control the degree of polymerization of component polymers and can adjust the Flory–Huggins interaction parameter, χ, with the temperature, T, according to the relationship χ = 0.027–9.5/T, the phase behavior and the interfacial structure of PTMSS and PI are predictable by mean field theory. When the bilayer films of PTMSS and PI were set at 90 °C, which is a temperature below the LCST, diffusion at the interface was observed, and the original interface disappeared in several hours; this supports the idea that the polymer pair is miscible. No clear interfaces were identified below the LCST, whereas broad interfaces, compared with that of the strong segregation pairs, were observed above the LCST. The compositions of each layer are consistent with that of the coexisting phase in the polymer blends, and the interfacial widths agree well with the theoretical prediction considering the effect of capillary waves. In addition, all annealed films have a thin surface layer of PTMSS corresponding to surface segregation induced by the lower surface energy of PTMSS (with respect to that of PI). Thus, the interfacial profiles of PTMSS/PI bilayer films have been totally prospected in the framework of mean field theory. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1486–1494, 2005 相似文献
370.
We investigate atomic scale friction between clean graphite surfaces by using molecular dynamics. The simulation reproduces atomic scale stick-slip motion and a low frictional coefficient, both of which are observed in experiments using frictional force microscope. It is made clear that the microscopic origin of low frictional coefficients of graphite lies on the honeycomb structure of each layer, not only on the weak interlayer interaction as believed so far. 相似文献