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221.
Guksik Lee Fumito Araoka Ken Ishikawa Yuichi Momoi Osamu Haba Koichiro Yonetake Hideo Takezoe 《Particle & Particle Systems Characterization》2013,30(10):847-852
Ordering transitions are observed in azo‐dendrimer‐dissolved nematic liquid crystal (NLC) droplets dispersed in a glycerol matrix. The dendrimer molecules are spontaneously attached at the interface between NLC and glycerol, so that the nematic directors orient perpendicular to the interface, in the radial configuration. Photoisomerization makes the directors be tangential to the interface, in a photoinduced ordering transition from radial to bipolar structure. Similar experiments are conducted both in cholesteric (Ch) and smectic‐A (SmA) LC droplets. Complicated photoinduced ordering transitions are also observed in Ch and SmA droplets, and the associated molecular orientation changes are discussed. Photoisomerizable azo‐dendrimer molecules provide a possible way to control orientation, even in microdroplet systems in which the interface cannot be treated by conventional surface agents. 相似文献
222.
Takahito Itoh Motoka Ikeda Nobuyuki Hirata Yuji Moriya Zhaoyin Wen Yoshiaki Ichikawa Masataka Kubo Osamu Yamamoto 《Ionics》2002,8(1-2):44-52
Terminal-acetylated hyperbranched poly(ethylene glycol) derivatives containing diethylene, triethylene, and hexaethylene and
3,5-dioxybenzoate branching units (poly-Ac1a, poly-Ac1b, and poly-Ac1c) were synthesized. Electrochemical and thermal properties of the hyperbranched polymer electrolytes with lithium salts such
as LiCF3SO3 and LiN(CF3SO2)2, the composite hyperbranched polymer electrolytes with LiN(CF3SO2)2 containing α-LiAlO2 and γ-LiAlO2 fillers, and the hyperbranched polymer blended poly(ethylene oxide) electrolytes with LiN(CF3SO2)2 were investigated and discussed.
Paper presented at the 8th EuroConference on Ionics, Carvoeire, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
223.
Osamu Moriue Masato Mikami Naoya Kojima Christian Eigenbrod 《Proceedings of the Combustion Institute》2005,30(2):1973-1980
Spontaneous ignition of single n-heptane droplets in a constant volume filled with air is numerically simulated with the spherical symmetry. The volume is closed against mass, species, and energy transfer. The numerical model is fully transient. It continues calculation even after the droplet has completely vaporized, and therefore can predict pre-vaporized ignition. Initial pressure and initial air temperature are fixed at 3 MPa and 773 K, respectively. The droplet is initially at room temperature, and its diameter is between 1 and 100 μm. When the overall equivalence ratio is fixed to be sufficiently large, there exists no ignition limit in terms of initial droplet diameter d0, and the ignition delay takes a minimum value at certain d0. In such a case, transition from the heterogeneous ignition to the homogeneous ignition with decreasing d0 is observed. When d0 is fixed to be so small that the ignition would not occur in an infinite volume of air, the ignition delay takes a minimum value at certain , which is less than unity. Two-stage ignition behavior is investigated with this model. Ignition delay of a cool flame has the dependence on d0 that is similar to that of ignition delay of a hot flame when is unity. When is almost zero, the ignition limit for cool flame in terms of d0 is not identified unlike that for hot flame. 相似文献
224.
225.
Osamu Yamashita Kouji Satou Hirotaka Odahara Shoichi Tomiyoshi 《Journal of Physics and Chemistry of Solids》2005,66(7):1287-1293
The p-type (Bi0.25Sb0.75)2Te3 doped with 3-12 wt% excess Te alone and n-type Bi2(Te0.94Se0.06)3 codoped with 0.017-0.026 wt% Te and 0.068-0.102 wt% I were prepared by the Bridgman method, to produce intentionally polycrystalline. Some of the as-grown specimens were annealed, in order to prepare specimens with much different ρ. These polycrystalline specimens have almost the same degree of alignment of the c plane parallel to the freezing direction. The electrical rersistivity ρ and thermal conductivity κ were measured at 298 K along the freezing direction and κ was plotted as a function of ρ. As a result, the lattice components κph obtained by subtracting the electronic component κel from the observed κ were found to decrease almost linearly with a decrease of ρ in both p- and n-type specimens, where κel was calculated using Wiedemann-Franz law. This tendency is consistent with the conventional result that κph becomes negligible small in metals. The significant decrease in κph with decrease in ρ is considered to be caused predominantly by the phonon scattering due to dopants. The relationship between κph and ρ was first clarified in the intermediate region between the metal and insulator. 相似文献
226.
Osamu Kido Mami Kurumada Katsuya Kamitsuji Toshiaki Tanigaki Takeshi Sato Yuki Kimura Hitoshi Suzuki Yoshio Saito Chihiro Kaito 《Physica E: Low-dimensional Systems and Nanostructures》2006,31(2):169-173
The synthesis of Al–Cr single quasicrystal (QC) nanoparticles of the decagonal phase was achieved by introducing an advanced gas flow evaporation method. By obtaining successive electron diffraction patterns for single-QC nanoparticles, the phase transformation temperature of a single-QC nanoparticle was determined to be 700 °C. It was also determined that part of the QC nanoparticle decomposed into hex-Al8Cr5 and Al during the phase transformation. Since the grain growth did not occur during the phase transformation in the present experiment, the inherent phase transformation temperature could be measured. 相似文献
227.
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229.
Yoshihiro Furukawa Yutaka Nakabayashi Shichio Kawai Osamu Nakamura 《Solid State Ionics》1982,7(3):219-223
The protonic motion in NH+4-H+(H2O)nβ″ -alumina wasstudied by measurements of proton spin-lattice and spin-spin relaxation times. The results show that two types of NH+4 reorientation, that is, three-fold reorientation about its unique C3 axis and tumbling motion as a whole, occur below room temperature. Above room temperature a fast proton translational diffusion was apparent, and its activation energy was estimated to be 36 kJ/mol. On the other hand, the conductivity measured on a pressed sample by an ac method is strongly humidity-sensitiveand changes by more than five orders from 0 to 100% relative humidity. The activation energy also may be humidity-sensitive. Its value was 73 kJ/mol for the sample equilibrated at 90°C in a dry nitrogen atmosphere. 相似文献