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81.
Time-resolved reflectance of an optical pulse in adult head models including non-scattering cerebrospinal fluid (CSF) has been analyzed by the finite difference time domain (FDTD) analysis formulated by the authors. Averaged light intensity and mean time of flight dependences on the source-detector separations calculated by the FDTD analysis are in good agreement with previous experiments, hybrid finite element method (FEM) and Monte Carlo calculations, which justify the FDTD analysis. Based on the analysis, time-resolved reflectance sensitivities to detect optical property changes in brain have been analyzed. As a result, it has been become clear that the sensitivities to detect absorption changes of brain are enhanced in time-resolved reflectance compared to the sensitivities in averaged light intensity, whereas the sensitivities to detect scattering property changes of brain are almost the same in time-resolved reflectance and in averaged light intensity. © 2005 The Optical Society of Japan 相似文献
82.
Tomoyuki Maruyama Takumi Muto Toshitaka Tatsumi Kazuo Tsushima Anthony W. Thomas 《Nuclear Physics A》2005,760(3-4):319-345
The possibility of kaon condensation in high-density symmetric nuclear matter is investigated including both s- and p-wave kaon–baryon interactions within the relativistic mean-field (RMF) theory. Above a certain density, we have a collective state carrying the same quantum numbers as the antikaon. The appearance of the state is caused by the time component of the axial-vector interaction between kaons and baryons. It is shown that the system becomes unstable with respect to condensation of K– pairs. We consider how the effective baryon masses affect the kaon self-energy coming from the time component of the axial-vector interaction. Also, the role of the spatial component of the axial-vector interaction on the possible existence of the collective kaonic states is discussed in connection with Λ-mixing effects in the ground state of high-density matter. Implications of condensation for high-energy heavy-ion collisions are briefly mentioned. 相似文献
83.
Masuo Aizawa Yasuki Watanabe Shuichi Suzuki 《Applied biochemistry and biotechnology》1979,4(2):131-141
A thermal analyzer consisting of a pair of glass thermistors was coupled with a flowthrough immobilized enzyme reactor for the determination of ATP concentration. Hexokinase was covalently bound to poly(chloromethyl-styrene-divinyl benzene) beads and packed in the reactor. The thermal analyzer was designed so as to respond to heat generation in the reactor. A maximum temperature change was exhibited within 1.5 min after the injection of a sample solution containing ATP together with glucose. Thermal decay occurred within 1 min. The thermal analyzer responded reproducibly to ATP at a constant concentration. Assays could be repeated at 3-min intervals. The effects of sample volume and flow rate on the response were examined with regard to an empirical equation. Concentration of ATP was determined with the thermal analyzer in the range of 0-10 mM. The thermal analyzer may be a simple device for the rapid determination of ATP concentration. 相似文献
84.
85.
Tadashi Watabe Akira Hiratsuka Toshiko Aizawa Tadashi Sawahata 《Tetrahedron letters》1982,23(11):1185-1188
Synthesis of highly unstable vinyl-substituted benzene oxides has been established. 相似文献
86.
87.
A computer-generated hologram was recorded on a thermoplastic film using an electron-beam recording device. The hologram was a binary one of detour phase type and of surface relief type. A bright image was reconstructed from the recorded hologram. 相似文献
88.
Watano S Okamoto T Sato Y Ohnishi Y Yasutomo T Osako Y 《Chemical & pharmaceutical bulletin》2005,53(1):18-21
A novel multi-functional vertical high shear kneader has been developed and its performance in wet kneading has previously been reported [Watano et al., Chem. Pharm. Bull., 50(3), 341-345 (2002)]. In this study, scale-up of wet kneading in the novel vertical high shear kneader was conducted. Pharmaceutical excipients composed of lactose, cornstarch and micro-crystalline cellulose were used as powder samples. Kneading operations were conducted under various operating conditions and three different vessel scales. The dried pellets were then prepared by extruding the wet kneaded masses through a dome-type extruder and their drying by a fluidized bed. The physical properties such as strength and disintegration time of the dried pellets were evaluated. It was found that the properties of the dried pellets and their scale-up characteristics were well expressed by an agitation power per unit vessel volume and dimensionless Froude number. 相似文献
89.
Aizawa T Kanakubo M Hiejima Y Ikushima Y Smith RL 《The journal of physical chemistry. A》2005,109(33):7353-7358
Local density augmentation around exciplex between acetophenone and N,N,N',N'-tetramethylbenzidine in supercritical water was measured by observing the peak shift of transient absorption spectrum at temperatures from 380 to 410 degrees C and at pressures from 6 to 37 MPa. Large local density augmentation was observed at lower solvent densities. Local density augmentation was evaluated by the excess density, which was defined as the difference between local density and bulk density, and the density enhancement factor, which was defined by the ratio of the local density to the bulk density. The number of solvating molecules was estimated with a Langmuir adsorption model. The excess density was found to exhibit a maximum at approximately 0.15 g cm(-3), which decreased with increasing temperature. The density enhancement factor was found to decrease with increasing temperature; however, its value was much greater than unity at 410 degrees C, which provides evidence that exciplex-water interactions still exist at these conditions. The temperature dependence of local density augmentation around the exciplex in supercritical water was comparable with that in supercritical carbon dioxide, which suggests that the ratios of the solute-solvent and solvent-solvent interactions are comparable between these two systems. 相似文献
90.
Human blood group substance of the ABO system was immobilized in a mebrane matrix. The membrane-bound blood group substance retained its binding ability against the corresponding antibody (agglutinin) in serum. The transmembrane potential changed drastically with the agglutination of the membrane-bound blood group substance. Electrochemical typing of blood was performed with sera, using a pair of membranes with immobilized A- and B-type blood group substances. The blood type was determined by measuring the transmembrane potential across these membranes before and after the agglutination reaction. A possible re-use of the membrane-bound blood group substance by treatment with galactose is discussed. 相似文献