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151.
Miguel Vivas-Cortez Muhammad Aamir Ali Hüseyin Budak Humaira Kalsoom Praveen Agarwal 《Entropy (Basel, Switzerland)》2021,23(7)
In this investigation, for convex functions, some new –Hermite–Hadamard-type inequalities using the notions of derivative and integral are obtained. Furthermore, for -differentiable convex functions, some new () estimates for midpoint and trapezoidal-type inequalities using the notions of integral are offered. It is also shown that the newly proved results for and can be converted into some existing results. Finally, we discuss how the special means can be used to address newly discovered inequalities. 相似文献
152.
Praveen C. Ashok Bavishna B. Praveen Kishan Dholakia 《Journal of Raman spectroscopy : JRS》2013,44(6):795-797
We report a chemometric prediction of the toxicity and quality of liquor using an optofluidic sensor based upon Waveguide Confined Raman Spectroscopy (WCRS). The WCRS sensor was used to record the Raman spectra, each obtained from a 20 µl sample of a given alcoholic beverage with and acquisition time of 20 s. This was used to predict, simultaneously, both the methanol concentration (toxicity) and ethanol concentration (quality), with an accuracy of 0.1% and 0.7% by volume, respectively, using a Partial Least Squares‐based chemometric model. The model sensor is shown to be capable of identifying toxic liquors, based on the test performed on different types of liquor samples. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
153.
P. Lakshmi Praveen 《Phase Transitions》2013,86(5):433-441
This article describes the thermodynamic stability and phase behaviour of a liquid crystalline material p-n-hexyloxybenzylidene-p-toluidine (6OBT) at a molecular level. The atomic net charge and dipole moment at each atomic centre have been evaluated using the complete neglect differential overlap (CNDO/2) method. The modified Rayleigh–Schrodinger perturbation method along with multicentred-multipole expansion method has been employed to evaluate the long-range intermolecular interactions, while a ‘6-exp’ potential function has been assumed for the short-range interactions. The total interaction energy values obtained through these computations have been used to calculate the probability of each configuration at room temperature (300?K), nematic–isotropic transition temperature (346.9?K) and above transition temperature (400?K) using the Maxwell–Boltzmann formula. Further, the Helmholtz free energy and entropy of each configuration has been computed during the different modes of interactions. An attempt has been made to understand the phase behaviour and stability of the molecule based on thermodynamic parameters introduced in this article. 相似文献
154.
Increasing the stability of perovskite solar cells is one of the most important tasks in the photovoltaic industry. Thus, the structural, energetic, and electronic properties of pure CH3NH3PbI3 and fully doped compounds (CH3NH3PbBr3 and CH3NH3PbCl3) in cubic and tetragonal phases were investigated using density functional theory calculations. We also considered the effects of mixed halide perovskites CH3NH3PbI2X (where X = Br and Cl) and compared their properties with CH3NH3PbI3. The DFT results indicate that the phase transformation from tetragonal to cubic phase decreases the band gap. The calculated results show that the X‐site ion plays a vital role in the geometrical stability and electronic levels. An increase in the band gap and a reduction in the lattice constants are more apparent in CH3NH3PbI2X compounds (I > Br > Cl). 相似文献
155.
B.M. Praveen 《Applied Surface Science》2008,254(8):2418-2424
Nanosized TiO2 particles were prepared by sol-gel method. The TiO2 particles were co-deposited with zinc from a sulphate bath at pH 4.5 using electrodeposition technique. The corrosion behavior of the coatings was assessed by electrochemical polarization, impedance, weight-loss and salt spray tests. Wear resistance and microhardness of the composite coating was measured. The smaller grain size of the composite coatings was observed in the presence of TiO2 and it was confirmed by the images of scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. 相似文献
156.
Guang Liu Lakshmi Chakka Joseph E. Gadzia R. Suzuki N. Oshima 《Applied Surface Science》2008,255(1):115-118
Positronium annihilation lifetime (PAL) spectroscopy and Doppler broadening energy spectra (DBES) have been used to search for selectivity and sensitivity for cancerous skin samples with and without cancer. This study is to further explore the melanoma cancerous system and other different types of skin samples. We found that the S parameter in melanoma skin samples cut at 0.39 mm depth from the same patient's skin is smaller than near the skin surface. However in 10 melanoma samples from different patients, the S parameters vary significantly. Similarly, among 10 normal skin samples without cancer, the S parameters also vary largely among different patients. To understand the sensitivity of PAS as a tool to detect cancer formation at the early stage, we propose a controlled and systematic study of in vivo experiments using UV-induced cancer skin from living animals. 相似文献
157.
Shadap Lathewdeipor Tyagi Jaya Lakshmi Poluri Krishna Mohan Novikov Sergei Lo Chun-Wan Timothy Mozharivskyj Yurij Kollipara Mohan Rao 《Transition Metal Chemistry》2021,46(3):231-240
Transition Metal Chemistry - Metal complexes 1–9 have been synthesized by reacting the benzothiazole–pyrazole derivative ligands (L1, L2 and L3) with the metal precursors of ruthenium... 相似文献
158.
Journal of Solid State Electrochemistry - Nanostructured electrode materials for supercapacitors have attracted research interest due to their high power density and long cycle life. Herein, porous... 相似文献
159.
Lera Israel Leka Khasnabis Sutripto Wangatia Lodrick Makokha Femi Olu Emmanuel Ramamurthy Praveen C 《Journal of Solid State Electrochemistry》2022,26(1):195-209
Journal of Solid State Electrochemistry - Highly efficient, abundant, and low-cost materials are highly demanded for energy conversion applications to address the rising consumption of energy. In... 相似文献
160.
The Nickel (II) complexes [Ni(Cl)2(metf)(o-phen)] (1), [Ni(Cl)2(metf)(opda)] (2) , [Ni(Cl)2(metf)(en)] (3) , [Ni(Cl)2(metf)(2,2'-bipy)] (4) , (metf = metformin, o-phen = ortho-phenanthroline, opda = ortho-phenylenediamine, en = ethylenediamine, 2–2′ bipy = 2–2′ bipyridyl) were synthesized and characterized using LC–MS, elemental analysis, molar conductance measurements, TGA-DTA, IR spectroscopy, magnetic moment measurements and electronic spectroscopy. The central Ni2+ was found to be in octahedral geometry. The DNA interaction of these complexes have been studied by UV–visible absorption studies, fluorescence emission technique and viscosity measurement. The complexes showed absorption hyperchromism in UV–visible spectra with calf thymus DNA. The binding constants from UV–visible absorption studies were 7.42 × 104, 0.74 × 104, 3.19 × 104, 5.9 × 104 M−1 for 1 , 2 , 3 and 4 , respectively and Stern-Volmer quenching constants from fluorescence studies were 0.16, 0.41, 0.23, 0.18, respectively. Viscosity measurements revealed that the binding of the complexes with DNA could be surface binding, mainly due to groove binding. The highest DNA cleavage activity of the complexes is recorded for complex 1 . The complexes were docked in to B-DNA sequence, 5′(D*AP*CP*CP*GP*AP*CP* GP*TP*CP*GP*GP*T)-3′ retrieved from protein data bank (PDB ID: 423D), using Discovery Studio 2.1 software. C Docker Intectraction energy of 1 , 2 , 3 and 4 complexes is 32.027, 31.427, 35.393 and 30.521 respectively. The highest docking score is seen for complex 3 . 相似文献