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991.
Yoshio Hoei 《Journal of Macromolecular Science: Physics》2013,52(1):190-198
A complete equation of the swelling activity parameter (S) as a function of swelling deformation (λs ) is derived by using a non-Gaussian elastic network model, including a tube concept and the Flory–Rehner model, and by following McKenna's criterion that takes into account the disparity between the Flory–Huggins interaction parameters for cross-linked and uncross-linked polymers. However, only a part of tube at the network chain size scale is extended to that for a large-scale structure according to the “gel tensile blob” model for equilibrium swollen networks. This approach is basically best for the “ideal regular network + simple structured good-solvent” binary systems due to its model character. As a result, it reproduces well the literature data of S versus λs 2 with a maximum/inflection measured for such actual systems. 相似文献
992.
Yoshio Tanaka Hiromi Tsuchiya Minoru Suzuki Keishiro Tsuda Jiro Takano Hiroyuki Kurihara 《Molecular Crystals and Liquid Crystals》2013,570(1):113-125
Abstract The photoreaction of cholesteryl trans-cinnamate in K Br matrix was studied in the solid, mesomorphic and isotropic liquid states at 25?225°C, and compared with the solution reaction in n-hexane. Cholesteryl trans-cinnamate was converted into a dimer on irradiation at wave-length longer than 300 nm at these phases. The photoirradiation in the solution led to a cis-isomer at 25?30°C. The initial rate of the dimerization at the mesophase was found to be higher than that at the isotropic liquid phase. The photoreaction in the solid took place at a much slower rate than in the other states. These suggest that some kinds of ordering besides the mobility of the molecules of the cinnamate enhance the rate and affect the course of the reaction on irradiation in comparison with the reaction in the isotropic solution. 相似文献
993.
Mitsuhiro Hirai Shingo Mitsuya Hiroki Iwase Tomohiro Hayakawa Yasuaki Aoyama Ken Ohashi 《Molecular Crystals and Liquid Crystals》2013,570(1):641-650
Abstract We have developed a high-performance compact magnetic circuit to investigate orientational phase behaviors of biological and synthetic macromolecular systems by using spectroscopic methods such as X-ray scattering and light scattering. This magnetic circuit can apply a periodic magnetic field and gradient to samples. The maximum values of the magnetic field strength and gradient are varied from 1.5 tesla to 0.55 tesla and from 2.4 × 102 tesla/m to 7.3 × 101 tesla/m. Owing to the high periodicity of the magnetic field strength and gradient macromolecules are subjected to both rotational and translational forces from the magnetic field. We show some prominent features of this magnetic circuit and its first application to the synchrotron radiation small-angle X-ray scattering (SR-SAXS) studies of supermacromolecular liquid crystals. 相似文献
994.
Yoshio Watanabe 《Synchrotron Radiation News》2013,26(3)
Progress in nanofabrication technology has led to the development of nanostructure materials with characteristic physical properties and potential applications in micro- and optoelectronic devices. To evaluate such nanostructures, different spectroscopic techniques have been developed that can provide a nanometer-scale lateral resolution. The International Workshop on Nanoscale Spectroscopy (NSS) is a biennial meeting series to share information on the latest research advances of science and technology, which include various kinds of nanoscale spectroscopies; electronic, optical, magnetic, mechanical, and transport properties of nanoscale systems; nanoscale devices; and nanomanipulation. 相似文献
995.
996.
Satoshi Hasegawa Yoshio Hayasaki 《Applied Physics A: Materials Science & Processing》2013,111(3):929-934
Wavelength dispersion of a computer-generated hologram causes spatial broadening of the focal spot in holographic femtosecond laser processing. From the paraxial approximation, we theoretically derived that the spatial broadening is proportional to only the diffraction position, defined as the distance from the optical axis. We performed experiments under the large-dispersion condition to analyze the influence of the diffraction position on the processed structure. In the processing experiment, a high-numerical-aperture lens and a laser energy near the threshold energy were used to fabricate sub-microstructures. We found a nonlinear dependence of the broadening of the processed structures on the diffraction position, and the degree of broadening was much smaller than the predicted value because of the nonlinear properties of the laser processing. 相似文献
997.
Hongyu An Susumu Takada Takumi Sannomiya Shinji Muraishi Ji Shi Yoshio Nakamura 《Applied Physics A: Materials Science & Processing》2013,113(1):31-35
Magnetic properties and internal stresses of AlN(20 nm)/[CoPt(2 nm)/AlN(20 nm)]5 multilayer structure deposited at different substrate temperatures by dc magnetron sputtering have been studied. It is found that with increasing the substrate temperature from room temperature to 400 °C, in-plane magnetic anisotropy field of the film becomes smaller, and the out-of-plane magnetization becomes stronger. Especially when the film is deposited at substrate temperature of 400 °C, the out-of-plane magnetization becomes as strong as the in-plane magnetization. On the other hand, the total in-plane residual stress of the film changes gradually from compressive to tensile. The compressive intrinsic stress is generated during deposition process and decreases with increasing the substrate temperature. After annealing at high temperatures, the films show strong perpendicular magnetic anisotropy. With increasing the annealing temperature, the in-plane thermal stress also increases and becomes dominant, which is considered to result in the perpendicular magnetic anisotropy of the films. 相似文献
998.
We consider embedding deterministic Runge-Kutta methods with high order into weak order stochastic Runge-Kutta (SRK) methods for non-commutative stochastic differential equations (SDEs). As a result, we have obtained weak second order SRK methods which have good properties with respect to not only practical errors but also mean square stability. In our stability analysis, as well as a scalar test equation with complex-valued parameters, we have used a multi-dimensional non-commutative test SDE. The performance of our new schemes will be shown through comparisons with an efficient and optimal weak second order scheme proposed by Debrabant and Rößler (Appl. Numer. Math. 59:582–594, 2009). 相似文献
999.
Ichikawa T Yoshio M Hamasaki A Taguchi S Liu F Zeng XB Ungar G Ohno H Kato T 《Journal of the American Chemical Society》2012,134(5):2634-2643
Two series of wedge-shaped onium salts, one ammonium and the other phosphonium, having 3,4,5-tris(alkyloxy)benzyl moieties, exhibit thermotropic bicontinuous "gyroid" cubic (Cub(bi)) and hexagonal columnar liquid-crystalline (LC) phases by nanosegregation between ionophilic and ionophobic parts. The alkyl chain lengths on the cationic moieties, anion species, and alkyl chain lengths on the benzyl moieties have crucial effects on their thermotropic phase behavior. For example, triethyl-[3,4,5-tris(dodecyloxy)benzyl]ammonium hexafluorophosphate forms the thermotropic Ia3d Cub(bi) LC phase, whereas an analogous compound with trifluoromethanesulfonate anion shows no LC properties. Synchrotron small-angle diffraction intensities from the Ia3d Cub(bi) LC materials provide electron density maps in the bulk state. The resulting maps show convincingly that the Ia3d Cub(bi) structure is composed of three-dimensionally interconnected ion nanochannel networks surrounded by aliphatic domains. A novel differential mapping technique has been applied successfully. The map of triethyl-[3,4,5-tris(decyloxy)benzyl]ammonium tetrafluoroborate has been subtracted from that of the analogous ammonium salt with hexafluorophosphate anion in the Ia3d Cub(bi) phases. The differential map shows that the counteranions are located in the core of the three-dimensionally interconnected nanochannel networks. Changing from trimethyl- via triethyl- to tripropylammonium cation changes the phase from columnar to Cub(bi) to no mesophase, respectively. This sensitivity to the widened shape for the narrow end of the molecule is explained successfully by the previously proposed semiquantitative geometric model based on the radial distribution of volume in wedge-shaped molecules. The LC onium salts dissolve lithium tetrafluoroborate without losing the Ia3d Cub(bi) LC phase. The Cub(bi) LC materials exhibit efficient ion-transporting behavior as a result of their 3D interconnected ion nanochannel networks. The Ia3d Cub(bi) LC material formed by triethyl-[3,4,5-tris(decyloxy)benzyl]phosphonium tetrafluoroborate shows ionic conductivities higher than the analogous Ia3d Cub(bi) material based on ammonium salts. The present study indicates great potential of Cub(bi) LC nanostructures consisting of ionic molecules for development of transportation nanochannel materials. 相似文献
1000.
We report on the demonstration of Doppler-free polarization spectroscopy of the D2 line of (6)Li atoms. Counterintuitively, the presence of an Ar buffer gas, in a certain pressure range, causes a drastic enhancement of the polarization rotation signal. The observed dependence of the signal amplitude on the Ar buffer pressure and the pump laser power is reproduced by calculations based on simple rate equations. We performed stable laser frequency locking using a dispersion signal obtained by polarization spectroscopy for laser cooling of (6)Li atoms. 相似文献