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Two Auger electrons, one very slow, one fast, have been detected in coincidence following near threshold 4d photoionization of the Xe atom. The distribution in the energy the two electrons share has been measured for the first time revealing the presence of post-collision interaction effects that provide unique information on the decay dynamics of the 4d hole. Analysis of the distorted line shapes indicates that the dominant process is decay of Xe+(4d(-1)) to Xe3+ through cascade emission of a zero kinetic energy Auger electron followed by a fast Auger electron. The widths of the intermediate Xe2+* states are estimated to be about 60 meV.  相似文献   
94.
Preliminary results on the mechanical, optical and electrical properties of composite gel electrolytes (CGEs) with fumed silica (SiO2) as a filler added to gel polymeric electrolyte (GPE) based on PMMA, LiCF3SO3 and PC are presented in this paper. Added fumed silica is seen to enhance the mechanical properties of the GPE without changing the conductivity significantly. The high ionic conductivity (×10−3 S/cm), high transmission in the visible region and nominal variance of conductivity and viscosity over a wide temperature window show that these CGEs are potential electrolytes for electrochromic windows (ECWs).  相似文献   
95.

Research on anticancer properties of natural compounds, as effective materials that are available while causing minimal side effects, is growing. Ellagic acid (EA) is a well-known polyphenolic compound, which has been found in both free and complex modes in several medicinal plants such as pomegranate, walnut, and berries. Although many articles have reported anticancer properties for this compound, its mechanism of action has not been fully elucidated. In this study, we used several online and offline bioinformatics tools and databases to identify the mechanism of action of EA on various types of human malignancies including bladder, blood, breast, cervical, colorectal, liver, pancreas, and prostate cancers. In this context, after identifying and extracting EA-affected human genes/proteins that have been reported in various references, we built the related gene networks and determined functional hub genes. In addition, docking was performed to recognize target proteins that react directly with EA and are in fact most affected by this compound. Our findings revealed that EA exerts its anticancer effects by influencing specific hub genes in various types of cancers. Moreover, different cellular signaling pathways are affected by this natural compound. Generally, it turned out that EA probably exerts most of its anticancer activities, through induction of apoptosis, as well as P53 and WNT signaling pathways, and also by affecting the expression of several hub genes such as CDKN1A, CDK4, CDK2, CDK6, TP53, JUN, CCNA2, MAPK14, CDK1, and CCNB1 and especially interactions with some related proteins including P53, CDK6, and MAPK14.

  相似文献   
96.
The technique of collinear fast-beam laser spectroscopy has been used to measure the isotope shifts of the even-even isotopes of Hg (Z=80) in the mass range 182≤A≤198 at the on-line mass separator ISOLDE at CERN. The atomic transition studied (6s 6p 3 P 2- 6s7s 3 S 1,λ=546.1 nm) starts from a metastable state, which is populated in a quasi resonant charge transfer process. The resulting changes in nuclear mean square charge radii show clearly that182Hg follows the trend of the heavier, even, weakly oblate isotopes. Correspondingly the huge odd-even shape staggering in the light Hg isotopes continues and the nuclear shape staggering and shape coexistence persists down to the last isotope investigated,181Hg. An update of isotope shift and hyperfine structure data for181–206Hg is given, with a revised evaluation of the differences in nuclear mean square charge radii and of spectroscopic quadrupole moments.  相似文献   
97.
The structures of 2‐substituted malonamides, YCH(CONR1R2)CONR3R4 (Y = Br, SO2Me, CONH2, COMe, and NO2) were investigated. When Y = Br, R1R2 = R3R4 = HEt; Y = SO2Me, R1–R4 = H and for Y = CONH2 or CONHPh, R1–R4 = Me, the structure in solution is that of the amide tautomer. X‐ray crystallography shows solid‐state amide structures for Y = SO2Me or CONH2, R1–R4 = H. Nitromalonamide displays an enol structure in the solid state with a strong hydrogen bond (OO distance = 2.3730 Å at 100 K) and d(OH) ≠ d(OH). An apparently symmetric enol was observed in solution, even in appreciable percentages in highly polar solvents such as DMSO‐d6, but Kenol values decrease on increasing the solvent polarity. The N,N′‐dimethyl derivative is less enolic. Acetylmalonamides display a mixture of enol on the acetyl group and amide in non‐polar solvents, and only the amide in DMSO‐d6. DFT calculations gave the following order of pKenol values for Y: H > CONH2 > COMe ≥ COMe (on acetyl) ≥ MeSO2 > CN > NO2 in the gas phase, CHCl3, and DMSO. The enol on the C?O group is preferred to the aci‐nitro compound, and the N? O? HO?C is less favored than the C?O? HO?C hydrogen bond. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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Novel biopolymer electrolytes based on carboxymethyl kappa-carrageenan (CM?-carrageenan) and ionic liquid 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) have been successfully developed. Strong coordination and hydrogen bonding interaction of [Bmim]Cl with the biopolymer were detected by Fourier transform infrared (FTIR) spectroscopy. The efficient function of [Bmim]Cl as the charge carrier in the system was reflected by electrochemical impedance spectroscopy (EIS) where the highest ionic conductivity (σ) of (5.76 ± 0.20) × 10?3 S cm?1 was achieved at ambient temperature (298 K) upon 30 wt.% of [Bmim]Cl inclusion. X-ray diffraction (XRD) analysis confirmed that the addition of ionic liquid did not alter the prominent amorphous phase of CM?-carrageenan. Analysis of scanning electron microscopy (SEM) proved the strong interaction of [Bmim]Cl with the biopolymer matrix. The highest conducting biopolymer electrolyte showed an electrochemical stability up to 3.0 V, whereas the transference number measurement revealed that ions are the major elements that contribute to the conductivity with 0.970 ion transference number.  相似文献   
100.
Image sharing scheme based on combination theory   总被引:1,自引:0,他引:1  
We present a simple algorithm for sharing and hiding secret image based on combination theory. The secret image is firstly encrypted by matrix multiplications and then shared into many shadow images by multiplying binary random sampling matrices. The sampling matrices randomly assign the pixel values to the shadow images which satisfy a specific combination rule as a constrain, so that the (tn) threshold secret sharing scheme can be implemented. Numerical experiments have demonstrated the effectiveness of this image sharing algorithm.  相似文献   
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