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901.
J. K. Ahn 《Few-Body Systems》2013,54(7-10):1043-1046
While the results of partial-wave analyses agree on the properties of the S = ?1 hyperon resonances (S 01Λ(1670), D 03Λ(1690), and D 13Σ(1670)), there is some disagreement between production and formation experiments in this mass region. Formation experiments observe one Σ resonance in the 1,670 MeV mass region with J p = 3/2? and decaying primarily to ${N\overline{K}, \Lambda\pi}$ , and Σπ. On the other hand, production experiments have found evidence suggesting two Σ resonances in this mass region with comparable values of mass and width. Photoproduction of the hyperon resonances in the Σ(1670) region was measured from the proton in the energy from threshold to 3.0 GeV. Preliminary results from LEPS show some indication of possible different lineshapes and yields in π ? Σ+ and π + Σ? decay modes, which encourage further study in analogy of the Λ(1405).  相似文献   
902.
The CLAS collaboration and the CBELSA/TAPS collaboration reported the differential cross section data for K*0 photoproduction, and found that the t-channel K exchange dominates the production amplitudes at small scattering angles. The measurement of forward-angle parity spin asymmetry for the γ pK*0Σ+ reaction, where the theoretical calculations show an unambiguous signal, would establish the role of the κ(800). The γ pK*0Σ+ reaction, where the Σ+ was identified through missing mass, on a liquid hydrogen target was measured at the LEPS detector in the energy from threshold to 3.0 GeV by using a linearly polarized photon beam at SPring-8. Decay angular distributions in the rest frame of the K + π ? system were fit to extract spin-density matrix elements of the K*0 decay.  相似文献   
903.
Detailed information on the location and the size of tumor cells circulating through lymphatic and blood vessels is useful to cancer diagnosis. Metastasis of cancers to other non‐adjacent organs is reported to cause 90% of deaths not from the primary tumors. Therefore, effective detection of circulating tumors cells (CTCs) related to metastasis is emphasized in cancer treatments. With the use of synchrotron X‐ray micro‐imaging techniques, high‐resolution images of individual flowing tumor cells were obtained. Positively charged gold nanoparticles (AuNPs) which were inappropriate for incorporation into human red blood cells were selectively incorporated into tumor cells to enhance the image contrast. This approach enables images of individual cancer cells and temporal movements of CTCs to be captured by the high X‐ray absorption efficiency of selectively incorporated AuNPs. This new technology for in vivo imaging of CTCs would contribute to improve cancer diagnosis and cancer therapy prognosis.  相似文献   
904.
Recent studies have suggested fatigue damage counting of a linear elastic system using only the output data; design sensitivity analysis based on the transmissibility function was studied in order to identify the most sensitive response location under intact conditions. The design sensitivity index was derived to be proportional to the response energy at the measured point through reformulation of the previous equation for the sensitivity index. The accuracy of the damage counting method can be enhanced with design sensitivity analysis by selecting the location with the maximum response energy; the method is optimally robust against unexpected noise in the output data. Simulation and testing of a notched simple specimen under uniaxial excitation were used to verify that sensitivity analysis enhances the accuracy of the predicted damage counting.  相似文献   
905.
In this paper we applied differential evolution (DE) algorithm to balance the tradeoff between robustness and imperceptibility by exploring multiple scaling factors in image watermarking. First of all, the original image is partitioned into blocks and the blocks are transformed into Discrete Cosine Transform (DCT) domain. The DC coefficients from each block are collected to construct a low-resolution approximation image and apply Singular Value Decomposition (SVD) on this approximation image. After that watermark is embedded by modifying singular values with the singular values of the watermark. The role of DE algorithm is to identify the best multiple scaling factors for embedding process in order to achieve the best performance in terms of robustness without compromising with the quality of the image. To enhance the security, watermark is scrambled by Arnold transform before embedding. Experimental results show that the proposed scheme maintains a satisfactory image quality and watermark can still be identified from a seriously distorted image.  相似文献   
906.
Quantitative MRI of neuromelanin (NM) containing structures (referred to as NM-MRI) in the brainstem, namely the locus coeruleus (LC) and substantia nigra (SN), may assist with the early detection of Parkinson’s disease (PD) and Alzheimer’s disease (AD) as well as differential diagnosis in the early disease stages. In this study, two gradient echo (GRE) sequences with magnetization transfer contrast (MTC) preparation pulses were developed to simultaneously image the LC and SN. This has been a challenge with NM-MRI techniques used in previous studies due to the relatively high specific absorption rate (SAR) induced by these techniques. In addition, a semi-automated quantitative analysis scheme was applied to estimate volumes and contrast-to-noise ratios (CNR) of the LC and SN based on segmentation of both structures. Compared to a T1-weighted turbo spin echo (TSE) sequence typically used for simultaneous imaging of the LC and SN, the two GRE-MTC sequences exhibited improved performance in terms of higher sensitivity (in CNR) in imaging the SN and lower SAR during the scans. A multiple-measurement protocol was adopted as well so that motion degraded measurements could be removed and artifacts associated with motion could be corrected. The present approach has demonstrated advantages in image acquisition (lower SAR and higher sensitivity), image pre-processing (with motion correction) and quantitative image analysis (segmentation-based estimation of volume and CNR) when compared with existing NM-MRI approaches. This approach has potential for detection and monitoring of neurodegeneration in LC and SN in disease states including AD and PD.  相似文献   
907.
This paper deals with the delay-dependent exponentially convergent state estimation problem for delayed switched neural networks. A set of delay-dependent criteria is derived under which the resulting estimation error system is exponentially stable. It is shown that the gain matrix of the proposed state estimator is characterised in terms of the solution to a set of linear matrix inequalities (LMIs), which can be checked readily by using some standard numerical packages. An illustrative example is given to demonstrate the effectiveness of the proposed state estimator.  相似文献   
908.
We demonstrate here a simple but very effective approach to decorate anodically grown TiO2 nanotubes (NTs) uniformly with CdS and PbS quantum dots (QDs) deep inside the NT walls. This approach is based on SILAR (successive ionic layer adsorption and reaction) technique assisted with evacuation of the NTs. The basic idea of evacuation is to remove air pockets trapped inside the NTs so as to clear the passage for the penetration of QD precursors down the bottom of the NTs.

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909.
910.
The solid cathode processing is necessary to separate salt from the cathode product for the preparation of a uranium ingot with a high purity in the pyroprocess. The capacity of a salt distiller should be sufficiently large to reach the throughput of uranium electro-refining process. In this study, an assembly composing a liquid separation sieve and a distillation crucible was developed for the sequential operation of a liquid salt separation and a vacuum distillation in the same tower. The feasibility of the sequential salt separation was examined by the rotation test of the sieve-crucible assembly and sequential operation of a liquid salt separation and a vacuum distillation. The adhered salt in the uranium deposits was removed successfully. The salt content in the deposits was below 0.1 wt% after the sequential operation of the liquid salt separation—salt distillation. From the results of this study, it could be concluded that efficient salt separation can be realized by the sequential operation of liquid salt separation and vacuum distillation in one distillation tower since the operation procedures are simplified and no extra operation of cooling and reheating is necessary.  相似文献   
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