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991.
E. Shiratori K. Ikegami F. Yoshida 《Journal of the mechanics and physics of solids》1979,27(3):213-229
A method of analyzing plastic behavior by use of an anisotropic hardening plastic potential is proposed. The plastic potential surface in deviatoric stress space is assumed to be the same as the equi-plastic-strain surface. Stress-strain relations in combined loading and in multi-axial cyclic loading are calculated by use of the anisotropic hardening plastic potential and the normality rule of the plastic strain increment vector to the plastic potential surface, which are experimentally determined or confirmed by subjecting thinwalled tubular test specimens of brass to combined axial load, internal pressure and torsion. The calculated results agree fairly well with the experimental observations. 相似文献
992.
The effect of shock pressures on the inactivation of a marine Vibrio sp. was studied experimentally and numerically. In the experiment, an aluminum impactor plate accelerated by a gas gun was
used to induce shock waves in a sealed aluminum container with cell suspension liquid inside. The shock pressures in the container
were measured by a piezofilm gauge. Several 10–100 MPa of pressure were measured at the shock wave front. An FEM simulation,
using the Johnson–Cook model for solid aluminum and the Tait equation for the suspension liquid, was carried out in order
to know the generation mechanism of shock pressures in the aluminum container. The reflection, diffraction and interaction
of shock waves at the solid–liquid boundaries in the aluminum container were reasonably predicted by the numerical simulation.
The changes in shock pressures obtained from the computational simulation were in good agreement with those from the experiment.
The number of viable cells decreased with the increase of peak pressures of the shock waves. Peak pressures higher than 200 MPa
completely inactivated the cells. At this pressure, the cell structures were deformed like the shape of red blood cells, and
some proteins leaked from the cells. These results indicate that the positive and negative pressure fluctuations generated
by shock waves contribute to the inactivation of the marine Vibrio sp.
相似文献
993.
Masaaki Hori Mariko Yoshida Kazumasa Yokoyama Koji Kamagata Fumitaka Kumagai Issei Fukunaga Kouhei Kamiya Michimasa Suzuki Yoshitaka Masutani Nozomi Hamasaki Yuriko Suzuki Shinsuke Kyogoku Nobutaka Hattori Shigeki Aoki 《Magnetic resonance imaging》2014
Introduction
Diffusion tensor imaging (DTI) reveals white matter pathology in patients with multiple sclerosis (MS). A recent non-Gaussian diffusion imaging technique, q-space imaging (QSI), may provide several advantages over conventional MRI techniques in regard to in vivo evaluation of the disease process in patients with MS. The purpose of this study is to investigate the use of root mean square displacement (RMSD) derived from QSI data to characterize plaques, periplaque white matter (PWM), and normal-appearing white matter (NAWM) in patients with MS.Methods
We generated apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps by using conventional DTI data from 21 MS patients; we generated RMSD maps by using QSI data from these patients. We used the Steel–Dwass test to compare the diffusion metrics of regions of interest in plaques, PWM, and NAWM.Results
ADC differed (P < 0.05) between plaques and PWM and between plaques and NAWM. FA differed (P < 0.05) between plaques and NAWM. RMSD differed (P < 0.05) between plaques and PWM, plaques and NAWM, and PWM and NAWM.Conclusion
RMSD values from QSI may reflect microstructural changes and white-matter damage in patients with MS with higher sensitivity than do conventional ADC and FA values. 相似文献994.
We consider adaptive Bayesian estimation of both drift and diffusion coefficient parameters for ergodic multidimensional diffusion processes based on sampled data. Under a general condition on the discretization step of the sampled data, three kinds of adaptive Bayes type estimators are proposed by applying adaptive maximum likelihood type methods of Uchida and Yoshida (Stoch Process Appl 122:2885–2924, 2012) to Bayesian procedures. We show asymptotic normality and convergence of moments for the adaptive Bayes type estimators by means of the Ibragimov–Has’minskii–Kutoyants program together with the polynomial type large deviation inequality for the statistical random field. 相似文献
995.
In this article, we demonstrate the fabrication and simultaneous fluorescent detection of two biomarkers related to lung cancer. Polystyrene microspheres (PSM) were introduced as biomolecular immobilizing carriers and a 96-well filter plate was used as the separation platform. The whole experiment could be effectively carried out in a homogeneous system, as exemplified by the detection of carcinoembryonic antigen (CEA) and neuron specific enolase (NSE). First, two capture antibodies for CEA and NSE were immobilized on the PSM surface. Next, they reacted successively with two antigens and two modified detection antibodies. Finally, these two biomarkers could be recognized by streptavidin-conjugated quantum dots (QD) and goat-anti-FITC conjugated QD with a detection limit of 0.625 ng mL(-1), which was lower than the clinical cut-off level. The protocol showed good precision within 6.36% and good recovery in the range of 90.86-105.02%. Compared with several other assay formats reported previously, our new technique is competitive or even better. Furthermore, the immunosensor was successfully illustrated in 20 serum samples. Overall, this new immunoassay offers a promising alternative for the detection of biomarkers related to cancer diseases, taking advantage of simplicity, specificity, sensitivity and cost-efficiency. 相似文献
996.
Formal meta-specific intramolecular Friedel–Crafts allylic alkylation of phenols was achieved based on spirocyclization–dienone–phenol rearrangement cascades. Systematic screening of acid catalysts revealed that Sc(OTf)3 was a highly effective catalyst for dienone–phenol rearrangement of spiro[4.5]cyclohexadienones. Using 5 mol % of Sc(OTf)3 as the promoter, various spirocyclic substrates were transformed into the corresponding phenol derivatives in good to excellent yield. Furthermore, the one-pot sequential spirocyclization–dienone–phenol rearrangement proceeded using a palladium and scandium multi-catalytic system or a triphenylmethyl cation single-catalyst system, providing the corresponding meta-allylated phenol derivatives in excellent yield. 相似文献
997.
João B. Fernandes Regina L. Fraga Milton D. Capelato Paulo C. Vierira Massayoshi Yoshida Massuo J. Kato 《合成通讯》2013,43(12-13):1331-1336
the use of electrochemical oxidation was applied to the synthesis of dibenzocyclooctadiene lactones related to steganacin skeleton. This reaction, performed with compounds 1 and 2, led to results comparable with the oxidation with RuTFA, TTFA and VOF3. 相似文献
998.
Hydrolysis or methanolysis of 4(a)-(trifluoromethyl-sulfonyloxy)adamantan-2-one affords 4(e)-hydroxy-or 4(e)-methoxyadamantan-2-one, respectively, as major product, both of which are easily separated from minor by-products. 相似文献
999.
Eri Yoshida 《Colloid and polymer science》2013,291(11):2733-2739
Giant vesicles with several-micrometer diameters were prepared by self-assembly induced by the nitroxide-mediated photo-controlled/living radical polymerization. The random block copolymerization of methyl methacrylate (MMA) and methacrylic acid (MAA) were performed using poly(methacrylic acid) (PMAA) as the prepolymer in an aqueous methanol solution to produce a PMAA-block-poly(MMA-random-MAA) random block copolymer (PMAA-b-P(MMA-r-MAA)). PMAA195-b-P(MMA0.817-r-MAA0.183)224 formed spherical vesicles with a 4.74 μm diameter and 0.108 μm wall thickness. A differential scanning calorimetry analysis demonstrated that the vesicles had a bilayer structure consisting of a hydrophilic PMAA surface and hydrophobic P(MMA-r-MAA) interface. The wet vesicles before air-drying were flexible and easily transformed by stress, whereas the dry vesicles were fragile and cracked. The vesicles in the solution were dissociated into much smaller vesicles by increasing the temperature. They were also transformed by a further temperature increase into hollow fibers and finally into membranes retaining the bilayer structure. 相似文献
1000.
Naruyoshi Komiya Koichi Takahashi Tomoya Tanaka Atsushi Yoshida Takeshi Naota 《Transition Metal Chemistry》2013,38(6):659-664
The synthesis, structure, and conformational mobility of a trans-bis(aminophenolato)platinum(II) complex bearing a dodecamethylene bridge, [Pt(L)] (1) [H 2 L = N,N′-Dimethyl-N,N′-bis(2-hydroxyphenylmethyl)dodecane-1,12-diamine] are described. The 2D NMR and X-ray diffraction analysis revealed that the complex has a “reversed U”-shaped syn conformation in the solution state, which is mainly due to steric congestion of the vaulted structure and hydrogen bonding at the bis[(o-aminomethyl)phenolato] coordination site, while the complex unit is packed in the crystalline state with “Z-shaped” anti-conformation due to highly regulated molecular arrangement by 3D CH-π and hydrogen bonding interactions. 相似文献