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51.
Extraction of relevant lip features is of continuing interest in the visual speech domain. Using end-to-end feature extraction can produce good results, but at the cost of the results being difficult for humans to comprehend and relate to. We present a new, lightweight feature extraction approach, motivated by human-centric glimpse-based psychological research into facial barcodes, and demonstrate that these simple, easy to extract 3D geometric features (produced using Gabor-based image patches), can successfully be used for speech recognition with LSTM-based machine learning. This approach can successfully extract low dimensionality lip parameters with a minimum of processing. One key difference between using these Gabor-based features and using other features such as traditional DCT, or the current fashion for CNN features is that these are human-centric features that can be visualised and analysed by humans. This means that it is easier to explain and visualise the results. They can also be used for reliable speech recognition, as demonstrated using the Grid corpus. Results for overlapping speakers using our lightweight system gave a recognition rate of over 82%, which compares well to less explainable features in the literature.  相似文献   
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As an effective separation tool, free-flow electrophoresis has not been used for purification of low-abundance protein in complex sample matrix. Herein, lysozyme in complex egg white matrix was chosen as the model protein for demonstrating the purification of low-content peptide via an FFE coupled with gel fitration chromatography (GFC). The crude lysozyme in egg while was first separated via free-flow zone electrophoresis (FFZE). After that, the fractions with lysozyme activity were condensed via lyophilization. Thereafter, the condensed fractions were further purified via a GFC of Sephadex G50. In all of the experiments, a special poly(acrylamide- co-acrylic acid) (P(AM-co-AA)) gel electrophoresis and a mass spectrometry were used for identification of lysozyme. The conditions of FFZE were optimized as follows: 130 μL/min sample flow rate, 4.9 mL/min background buffer of 20 mM pH 5.5 Tris-Acetic acid, 350 V, and 14 °C as well as 2 mg/mL protein content of crude sample. It was found that the purified lysozyme had the purity of 80% and high activity as compared with its crude sample with only 1.4% content and undetectable activity. The recoveries in the first and second separative steps were 65% and 82%, respectively, and the total recovery was about 53.3%. The reasons of low recovery might be induced by diffusion of lysozyme out off P(AM-co-AA) gel and co-removing of high-abundance egg ovalbumin. All these results indicated FFE could be used as alternative tool for purification of target solute with low abundance.  相似文献   
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Hyaluronidase (Hyal) can be employed to accomplish a diversity of complications related to hyaluronic acid (HA). Hyal contains some classes of catalysts that cleave HA. This enzyme is detected in several human tissues as well as in animal venoms, pathogenic organisms and cancers. Destructive cancer cells regularly increase the CD44 receptor existing in a cell membrane. This receptor acts as an exact receptor for HA, and HA is recognized to motivate the migration, spread, attack and metastasis of cancer cells. Nearly all of the methods used to purify Hyal are highly costly and not proper for industrial applications. This survey aims to review different methods of Hyal purification, which acts as an anticancer agent by degrading HA in tissues and thus inhibiting the CD44–HA interaction. Hyal can be successfully employed in the management of cancer, which is associated with HA–CD44. This review has described different methods for Hyal purification to prepare an origin to develop a novel purification technique for this highly appreciated protein. Using multiple columns is not applicable for the purification of Hyal and thus cannot be used at the industrial level. It is better to use affinity chromatography of anti-Hyal for Hyal with one-step purification.  相似文献   
54.
Seven novel complexes (C1–C7) were synthesized by the interaction between Cu(I) metal cation, L1, L2, L3, X and PPh3, where L1–L3 are derivatives of ((pyridine-2-ylmethylene)amino)phenol imine ligands and X = Cl, Br, I, NCS. All the complexes were characterized using infrared, 1H NMR and 31P NMR spectroscopies. The crystal structures of C1–C7 were also determined using single-crystal X-ray diffraction. The organization of the crystal structures and the intermolecular interactions are discussed. The supramolecular assemblies are driven by cooperative π…π interactions and hydrogen bonds, followed by CH…π linkages. The potential anticancer effect of C1–C7 was assessed for human glioblastoma cells using several anticancer experiments, which showed that these complexes have marked anticancer property against U87 cells. It was also found that the minimum and maximum anticancer effects are shown by C3- and C4-treated samples, respectively. Furthermore, theoretical approaches were used to investigate the nature of metal–ligand interactions which suggest a closed-shell and electrostatic character for Cu…N, Cu…P and Cu…X bonds.  相似文献   
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In this work, the electrocatalytic reduction of dichloromethane (CH2Cl2) into hydrocarbons involving a main group element-based molecular triazole-porphyrin electrocatalyst H2PorT8 is reported. This catalyst converted CH2Cl2 in acetonitrile to various hydrocarbons (methane, ethane, and ethylene) with a Faradaic efficiency of 70 % and current density of −13 mA cm−2 at a potential of −2.2 V vs. Fc/Fc+ using water as a proton source. The findings of this study and its mechanistic interpretations demonstrated that H2PorT8 was an efficient and stable catalyst for the hydrodechlorination of CH2Cl2 and that main group catalysts could be potentially used for exploring new catalytic reaction mechanisms.  相似文献   
59.
Monolayer ZrO2 and TiO2 films were prepared on BK7 glass by physical vapor deposition (PVD) and were subsequently annealed for 1 h at 300 °C. By using the transmission spectra of two samples and the envelope method, the refractive index dispersion and extinction coefficients have been calculated. Laser induced damage threshold (LIDT) measurement shows that despite slight differences between the extinction coefficients of the two samples, the LIDT parameter of the ZrO2 film is greater than that of the TiO2 film. This fact leads us to consider thermal conductivity as an important parameter for interpreting the LIDT difference. According to our theoretical analysis, as a consequence of increase in the number of thermal barriers along poorer film, its thermal conductivity, and hence LIDT, decreased, which is in agreement with our experimental results. The measured porosity of the two samples shows higher porosity for TiO2 single layer, which is in agreement with atomic force (AFM) images. The gradual and smooth damage morphology of ZrO2 observed in optical images implies higher thermal conductivity than TiO2.  相似文献   
60.
The polydimethylsiloxane (PDMS) mixed matrix membrane with dispersed phase of nanozeolite silicalite-1 has been synthesized on polyethersulphone (PES) as a support, and its performance in the gas separation of xenon and krypton has been studied. For this purpose, nanozeolite silicalite-1 is synthesized by the hydrothermal clear solution method and is characterized by XRD and SEM analysis. In this research, the separation performance of MMM has also been compared with the polymeric PDMS membrane. Furthermore, the effect of feed pressure and loading percentage of nanozeolite in the polymeric matrix are evaluated. The results indicate that the addition of nanozeolite to the polymeric matrix improves its separation performance, and that the changes of the feed pressure have no major effect. The average permeability of the krypton and xenon gases through the PDMS polymeric membrane is calculated as 1.25 × 10?9 and 1.78 × 10?9 cm mol/(cm2 s kPa), respectively, while by adding only 5 wt% of nanosilicalite-1 to the polymeric matrix of the membrane, this amount increased to 1.82 × 10?9 and 8.07 × 10?9 cm mol/(cm2 s kPa), respectively. In addition, the presence of nanosilicalite-1 as the filler leads to an increase in the selectivity of xenon to krypton up to 4.38.  相似文献   
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