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61.
N-(substituted)-N'-(2,3-dihydro-5-benzoyl-2-oxido-1H-1,3,2-benzodiazaphosphol-2-yl) ureas were synthesized by reacting 3,4-diaminobenzophenone (4) with different chlorides of carbamidophosphoric acids (3) in the presence of triethylamine at 40-45 degrees C. Their 1H-, 13C- and 31P-NMR spectral data are discussed. The title compounds were screened for antifungal and antibacterial activity against the fungi Aspergillus niger and Fusarium solani and bacteria Escherichia coli and Staphylococcus aureus. These compounds showed higher antibacterial activity when compared with antifungal activity.  相似文献   
62.
CaTiO3:Pr3+ films were deposited on different substrates such as Al2O3 (0 0 0 1), Si (1 0 0), MgO (1 0 0), and fused silica using pulsed laser deposition method. The crystallinity and surface morphology of these films were investigated by XRD and SEM measurements. The films grown on the different substrates have different crystallinity and morphology. The FWHM of (2 0 0) peak are 0.18, 0.25, 0.28, and 0.30 for Al2O3 (0 0 0 1), Si (1 0 0), MgO (1 0 0), and fused silica, respectively. The grain sizes of phosphors grown on different substrates were estimated by using Scherrer's formula and the maximum crystallite size observed for the thin film grown on Al2O3 (0 0 0 1). The room temperature PL spectra exhibit only the red emission peak at 613 nm radiated from the transition of (1D2 → 3H4) and the maximum PL intensity for the films grown on the Al2O3 (0 0 0 1) is 1.1, 1.4, and 3.7 times higher than that of the CaTiO3:Pr3+ films grown on MgO (1 0 0), Si (1 0 0), and fused Sillica substrates, respectively. The crystallinity, surface morphology and luminescence spectra of thin-film phosphors were highly dependent on substrates.  相似文献   
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The recursion operator for the infinitesimal transformations about solutions of the coupled KdV is obtained as a 2 × 2 matrix.  相似文献   
66.
A Streptomyces sp. Lv3-13, isolated from the rhizosphere soil of the plant Mespilus germanica, has yielded three new pimprinine derivatives, named pimprinols A–C (13) and the unknown (2-aminophenyl)(2-ethyloxazol-5-yl) methanone (4) along with the known compounds 2-ethyl oxazole pimprinine and 2-propyl oxazole pimprinine. The structures of the compounds were elucidated based on spectroscopic methods including UV, HR-ESIMS and 1D, 2D NMR data. Compounds 14 were screened for antimicrobial and cytotoxic activities.  相似文献   
67.
Trace elemental imbalance in human beings is postulated to exert action, directly or indirectly, on the carcinogenic process. The objective of this study was to evaluate the levels of trace elements in blood sera of breast cancer patients and analyze their alteration with respect to healthy controls. This work was also intended to establish the role played by the trace elements in carcinogenic process. Particle induced X-ray emission (PIXE) technique was used for trace elemental analysis of blood sera of breast cancer patients and healthy controls. The PIXE measurements were carried out using a 2.5?MeV collimated proton beam from the 3 MV Tandem Pelletron accelerator at Institute of Physics, Bhubaneswar, India. On comparing the trace elemental content in the sera of breast cancer patients with those of control subjects, significant variations were observed in the levels of most of the trace elements. The serum levels of almost all the elements except Fe and Cu were observed to be depressed in cancer patients with respect to normal subjects. However, this variation was significant only for Ti (P?<?0.00005), Cr (P?<?0.005), Mn (P?<?0.0005), Ni (P?<?0.01), Zn (P?<?0.000001), and Se (P?<?0.05). On the other hand, significant elevations were observed in serum Fe (P?<?0.05) and Cu (P?<?0.005) levels in cancer patients. The findings presented in this paper give guidelines for future study into the possible roles and interactions of essential trace elements in the breast carcinogenic process.  相似文献   
68.
In this case study, we designed a farnesyl pyrophosphate (FPP) biosynthetic network using hybrid functional Petri net with extension (HFPNe) which is derived from traditional Petri net theory and allows easy modeling with graphical approach of various types of entities in the networks together. Our main objective is to improve the production of FPP in yeast, which is further converted to amorphadiene (AD), a precursor of artemisinin (antimalarial drug). Natively, mevalonate (MEV) pathway is present in yeast. Methyl erythritol phosphate pathways (MEP) are present only in higher plant plastids and eubacteria, but not present in yeast. IPP and DAMP are common isomeric intermediate in these two pathways, which immediately yields FPP. By integrating these two pathways in yeast, we augmented the FPP synthesis approximately two folds higher (431.16 U/pt) than in MEV pathway alone (259.91 U/pt) by using HFPNe technique. Further enhanced FPP levels converted to AD by amorphadiene synthase gene yielding 436.5 U/pt of AD which approximately two folds higher compared to the AD (258.5 U/pt) synthesized by MEV pathway exclusively. Simulation and validation processes performed using these models are reliable with identified biological information and data.  相似文献   
69.
A simple and rapid liquid chromatographic method for enantioselective separation and determination of R-(+) and S-(−) enantiomers of rabeprazole in drugs and pharmaceuticals using photo diode array (PDA) and polarimetric detectors connected in series was developed. Chiralpak AD-H (250 mm × 4.6 mm) 5 μm column packed with amylose tris(3,5-dimethylphenyl carbamate) as a stationary phase and the mobile phase containing n-hexane:ethanol:2-propanol(75:15:10, v/v/v) in an isocratic mode has yielded baseline separation with resolution greater than 3.0 at 40 °C. Effects of ethanol, 2-propanol and temperature on separation were studied for optimum resolution. Lansoprazole sulphone was used as an internal standard (IS) for quantitative determination of individual enantiomers in bulk drugs as well as pharmaceutical formulations. The method was validated in terms of accuracy, precision and linearity according to ICH guidelines. The linearity of the method was studied in the range of 0.5-50 μg/ml and the r2 was >0.9997. The inter- and intra-day precision of assay were determined (R.S.D. < 1%) and the recoveries were in the range of 99.63-100.22% with <1% R.S.D. The limits of detection (LOD) and quantification (LOQ) were 0.02 μg/ml and 0.07 μg/ml for both the enantiomers, respectively.  相似文献   
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