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61.
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
62.
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
63.
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
64.
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
65.
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
66.
Srinivas G. Ravi Kumar V. Laxma Reddy K. Praveen Kumar Y. Satyanarayana S. 《Russian Journal of General Chemistry》2018,88(12):2621-2627
Russian Journal of General Chemistry - A thiophene contained imidazo phenanthroline ligand TIP {TIP = 2-(thiophen-2-yl)-1H-imidazo-[4,5-f][1,10]phenanthroline{ and its mononuclear Ru(II)... 相似文献
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69.
Sharma PK Reilly MJ Bhatia SK Sakhitab N Archambault JD Bhatia SR 《Colloids and surfaces. B, Biointerfaces》2008,64(2):229-235
Pluronic F127, a triblock copolymer of poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO), has generated considerable interest as a drug delivery vehicle due to its ability to gel at physiological temperatures. This work examines the gelation behavior of Pluronic F127 in the presence of a series of hydrophobic pharmaceuticals, to determine whether there is any correlation between gelation and physicochemical parameters of drug solutes. The study includes the local anesthetics dibucaine, lidocaine, and tetracaine; the pharmaceutical additives methyl paraben, ethyl paraben, and propyl paraben; the anti-cancer agents paclitaxel and baccatin III; and the anti-inflammatory agent sulindac. The results indicate that the presence of local anesthetics and pharmaceutical additives allows F127 solutions to form gels at lower copolymer concentrations; local anesthetics and pharmaceutical additives also shift gelation down to a lower gelation temperature. This behavior is strongly dependent on drug solubility; poorly soluble drugs (paclitaxel, baccatin III, sulindac) do not change the lower gelation temperature or minimum F127 concentration for gelation. An equation relating the decrease in gelation temperature to drug solubility is presented, and the equation fits the data well. The results have significant positive implications on the toxicity and economic issues related to use of Pluronic F127 in drug delivery. 相似文献
70.
Sharma PK Reilly MJ Jones DN Robinson PM Bhatia SR 《Colloids and surfaces. B, Biointerfaces》2008,61(1):53-60
We present results on the effects of various hydrophobic drugs and additives on the micellar structure of Pluronic F127 solutions. Small-angle neutron scattering experiments on 5wt% F127 solutions were used to measure micelle core size (R(1)), micelle corona size (R(2)), intermicellar interaction distance (R(int)), polydispersity (sigma), and aggregation number (N(agg)); dynamic light scattering was used to measure critical micelle concentration (CMC); and ultraviolet spectroscopy was used to measure drug solubility and apparent micelle-water partition coefficient (K(mw)). The core and corona size were found to generally increase in the presence of the drugs, as did R(int). Both sigma and N(agg) were found to decrease in the presence of most of the drugs, and the CMC was found to vary considerably with no clear correlation. A design of experiments (DOE) approach was used to analyze the results and build empirical correlations. All of the parameters from the SANS experiments were found to depend strongly on drug solubility, with a weak dependence on K(mw) in most cases. The aggregation number, however, was found to depend strongly on both K(mw) and solubility. The correlations can be used to roughly predict the structural parameters of F127 micelles for other hydrophobic drugs. 相似文献