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981.
Miyake H Yoshida K Sugimoto H Tsukube H 《Journal of the American Chemical Society》2004,126(21):6524-6525
The helical chirality of a Co(II) complex with a chiral tetradentate ligand is completely inverted from Lambda to Delta by the addition of achiral NO3- anion as an external stimulus. 相似文献
982.
Development of dimethyl sulfoxide biosensor using a mediator immobilized enzyme electrode 总被引:2,自引:0,他引:2
A mediator immobilized dimethyl sulfoxide (DMSO) sensor using DMSO reductase (DMSO-R) was constructed. Methyl viologen (MV) was used as a mediator and immobilized on a glassy carbon (GC) electrode with Nafion polymer. DMSO-R from Rhodobacter sphaeroides f. sp. denitrificans was retained by a dialysis film on the modified GC electrode. The amperometric signal in response to DMSO was observed. The linear range of the calibration curve for DMSO was between 0 and 600 microM. The response time was within 100 s and the relative standard deviation was 4% at 200 microM DMSO (n = 4). To eliminate the background noise derived from oxygen in samples, the glucose oxidase-catalase retained DMSO sensor was also examined. 相似文献
983.
984.
Adler S Atiya MS Chiang IH Diwan MV Frank JS Haggerty JS Kettell SH Kycia TF Li KK Littenberg LS Sambamurti A Stevens A Strand RC Witzig C Komatsubara TK Kuriki M Muramatsu N Sugimoto S Inagaki T Kabe S Kobayashi M Kuno Y Sato T Shinkawa T Yoshimura Y Kishi Y 《Physical review letters》2000,85(11):2256-2259
We report the first measurement of a structure-dependent component in the decay K+-->&mgr;(+)nu(&mgr;)gamma. Using the kinematic region where the muon kinetic energy is greater than 137 MeV and the photon energy is greater than 90 MeV, we find that the absolute value of the sum of the vector and axial-vector form factors is |F(V)+F(A)| = 0.165+/-0.007+/-0.011. This corresponds to a branching ratio of B(SD+) = (1.33+/-0.12+/-0.18)x10(-5). We also set the limit -0. 04相似文献
985.
Mitsuru Furuya Naoki Shimono Kazuyuki Yamazaki Ryota Domura Masami Okamoto 《Materials Today Chemistry》2017
To broaden the knowledge of cytotoxicity of natural rubber latex (NRL) nanoparticles we for the first time examined the latex biocompatibility in vitro against a panel of cancer cells (A549, A2780, and MDA-MB-231). Owing to fractionation of NRL nanoparticles by ultra-centrifuge, the effect of the non-rubber constituents (intermediate of 5.8 wt% and sediment of 0.2 wt%) on the cytotoxicity was clarified. For intermediate constituent, the half maximal inhibitory concentration (IC50) values at 24 h was 1.05 mg/mL for A549 cells, which was one order of magnitude higher in toxicity as compared to that for A2780 (0.24 mg/mL) and MDA-MB-231 (0.36 mg/mL) cells. In addition, profound studies including cell cycle arrest abilities and apoptosis induction profiles against cancer cells were discussed in detail. It was found that the constituents exhibit some significant effect on the cell cycle arrest and trigger apoptosis for A2780 cells. This effective apoptosis induction profiles was more prominent in MDA-MB-231 cells incubated with NRL nanoparticles and sediment loading conditions. The percentage of apoptotic cells was ca. 6–8% of the total cells. 相似文献
986.
Kyu Hyun Kyung Hyun Ahn Seung Jong Lee Masataka Sugimoto Kiyohito Koyama 《Rheologica Acta》2006,46(1):123-129
In this study, linear and branched polypropylenes (PP) were compared under medium strain amplitude oscillatory shear (usually
strain amplitude range from 10 to 100%) with Fourier-transform rheology (FT rheology). On a log–log diagram, the third relative
intensity (I
3/I
1), which is a parameter to represent nonlinearity, shows a linear relationship with the strain amplitude in the range of medium
strain amplitude. The slope of I
3/I
1 of linear PP with various molecular weight and molecular weight distribution was 2 as most constitutive equations predict,
while that of branched PP was 1.64, which is lower than that of linear PP. When the linear and branch PP were blended, the
slope of I
3/I
1 was proportional to the composition of the branch PP. Therefore, it is suggested that the degree of branching can be defined
in terms of the slope of I
3/I
1 under medium amplitude oscillatory shear. 相似文献
987.
Melt rheology of long-chain-branched polypropylenes 总被引:2,自引:0,他引:2
Masataka Sugimoto Yasuhiro Suzuki Kyu Hyun Kyung Hyun Ahn Tsutomu Ushioda Akihiro Nishioka Takashi Taniguchi Kiyohito Koyama 《Rheologica Acta》2006,46(1):33-44
Rheological properties of long-chain-branched isotactic polypropylene (PP) via copolymerization with a very small amount of
nonconjugated α,ω-diene monomer using metallocene catalyst system in both linear and nonlinear regions were investigated,
comparing with conventional linear and long-chain-branched PP modified at postreactor. Although comonomer incorporation was
equal to 0.05 mol% or less, it caused high molecular weight, broad molecular weight distribution, and long-chain branching.
A detailed study on the effect of diene incorporation on the polymer properties was conducted, comparing with modified PP
in postreactor. Polymer chain microstructures were characterized by gel permeation chromatography with multiangle laser light
scattering (MALLS), differential scanning calorimetry, and rheological means: dynamic viscoelasticity, step-strain, uniaxial
elongational flow measurements, and large amplitude oscillatory shear. The PP, which incorporated a small amount of diene
monomer, showed significantly improved viscoelastic behaviors. The diene-propylene copolymer containing long-chain branches
showed extremely long relaxation mode under shear and outstanding viscosity increase under elongational flow, so-called strain
hardening. The difference in microstructure of diene-propylene copolymer with modified PP with long-chain branches is investigated
by MALLS and rheological characterizations. 相似文献
988.
Spontaneous gravity wave radiation from an unsteady rotational flow is investigated numerically in an f-plane shallow water system. Unlike the classical Rossby adjustment problem, where free development of an initially unbalanced state is investigated, we consider development of a barotropically unstable zonal flow which is initially balanced but maintained by zonal mean forcing. Gravity waves are continuously radiated from a nearly balanced rotational flow region even when the Froude number is so small that balance dynamics is thought to be a good approximation for the full system. The source of gravity waves is discussed by analogy with the theory of aero-acoustic sound wave radiation (the Lighthill theory). It is shown that the source regions correspond to regions of strong rotational flow. The gradual change of rotational flow causes gravity wave radiation. We propose an approximation for these strong sources on the assumption that the dominant flow in the jet region is non-divergent rotational flow. In addition, we calculate the zonally symmetric component of gravity waves far from the source regions, solving the Lighthill equation. Using scaling analyses for perturbations, these gravity waves can be calculated with only one approximated source term that is related to the latitudinal gradient of the fluid depth and the latitudinal mass flux. In spite of its simplicity, this approximation not only explains the physical cause of gravity wave radiation, but gives an amount of source close to that obtained by classical approximation derived from vortical motion. 相似文献
989.
FEM-FDM coupled liquefaction analysis of a porous soil using an elasto-plastic model 总被引:10,自引:0,他引:10
Fusao Oka Atsushi Yashima Toru Shibata Mitsuru Kato Ryosuke Uzuoka 《Applied Scientific Research》1994,52(3):209-245
The phenomenon of liquefaction is one of the most important subjects in Earthquake Engineering and Coastal Engineering. In the present study, the governing equations of such coupling problems as soil skeleton and pore water are obtained through application of the two-phase mixture theory. Using au-p (displacement of the solid phase-pore water pressure) formulation, a simple and practical numerical method for the liquefaction analysis is formulated. The finite difference method (FDM) is used for the spatial discretization of the continuity equation to define the pore water pressure at the center of the element, while the finite element method (FEM) is used for the spatial discretization of the equilibrium equation. FEM-FDM coupled analysis succeeds in reducing the degrees of freedom in the descretized equations. The accuracy of the proposed numerical method is addressed through a comparison of the numerical results and the analytical solutions for the transient response of saturated porous solids. An elasto-plastic constitutive model based on the non-linear kinematic hardening rule is formulated to describe the stress-strain behavior of granular materials under cyclic loading. Finally, the applicability of the proposed numerical method is examined. The following two numerical examples are analyzed in this study: (1) the behavior of seabed deposits under wave action, and (2) a numerical simulation of shaking table test of coal fly ash deposit. 相似文献
990.
Back Cover: Indolizino[5,6‐b]quinoxaline Derivatives: Intramolecular Charge Transfer Characters and NIR Fluorescence (Chem. Asian J. 11/2015)
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