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131.
Z. Jahangiri Tazekand M. Mohseni M. A. Mohammadi H. Sabri 《Brazilian Journal of Physics》2018,48(3):266-280
In this paper, we have considered the energy spectra, quadrupole transition probabilities, energy surface, charge radii, and quadrupole moment of the190Hg nucleus to describe the interplay between phase transitions and configuration mixing of intruder excitations. To this aim, we have used four different formalisms: (i) interacting boson model including configuration mixing, (ii) Z(5) critical symmetry, (iii) U(6)-based transitional Hamiltonian, and (iv) a transitional interacting boson model Hamiltonian in both interacting boson model (IBM)-1 and IBM-2 versions which are based on affine \( \widehat{SU\left(1,1\right)} \) Lie algebra. Results show the advantages of configuration mixing and transitional Hamiltonians, in particular IBM-2 formalism, to reproduce the experimental counterparts when the weight of spherical symmetry increased. 相似文献
132.
Fatemeh Sheikholeslami-Farahani Daryoush Zareyee Marziyeh Mohammadi Mahboubeh Ghasemian Samira Soltani 《Phosphorus, sulfur, and silicon and the related elements》2016,191(10):1334-1338
A series of polysubstituted cyclopentadienephosphonate derivatives were synthesized via one-pot multicomponent reactions of primary amines and phosphites with activated acetylenic compounds in water as the solvent at room temperature.Particularly valuable features of this method include high yields of products, broad substrate scope, short reaction time and a straightforward procedure. 相似文献
133.
Mohammad Bagher Majnooni Bahareh Mohammadi Ronak Jalili Gholamreza Bahrami 《液相色谱法及相关技术杂志》2016,39(19-20):877-881
A new high-performance liquid chromatographic method is described for the determination of fatty acids in seed oils. The method was based on precolumn derivatization with 9-fluorenylmethyl chloroformate as a labeling agent and fluorescence detection. Fatty acids were extracted from the samples and subjected to derivatization with the reagent at 60°C for 10?min. The chromatographic separation of 14 fatty acids (C10–C22) was achieved on a combined loading compression octadecyl sulfate (CLC-ODS) column with a run time of 30?min. Three-step gradient elution of a mobile phase consisted of acetonitrile and water was used, and the signal was monitored at excitation and emission wavelengths of 265 and 315?nm, respectively. The method indicated favorable sensitivity and reproducibility for fatty acids’ derivatives. The detection limits, at a signal-to-noise ratio of 3, were 0.01–0.05?µg/ml and relative standard deviations (RSDs) were less than 0.27%. Excellent linear responses were observed with coefficients of 0.9995. This method was applied to quantify fatty acids in white, brown, and black sesame seeds’ oil. 相似文献
134.
Mehdi Vaez-zadeh Ali Mohammadi 《Applied Physics A: Materials Science & Processing》2014,115(1):341-345
MnFe2O4 nanoparticles were prepared by a coprecipitation chemical method. The average size of the obtained nanoparticles was about 30 nm. The hysteresis measured at T=300 K clearly shows ferromagnetic order at room temperature while that measured at T=450 K shows superparamagnetic behavior. The difference in the magnetization curves in the field increasing cycle and field decreasing cycle at higher temperatures (450 K or higher) is very unusual. In this case, a hysteresis in magnetization in higher magnetic fields with an opening up of the magnetization curve was observed. In this work, the effect of temperature and time of application of the applied field on the magnetization behavior was studied. 相似文献
135.
Mohsen Doust Mohammadi Renjith Bhaskaran Hewa Y. Abdullah Hassan H. Abdallah George Biskos Somnath Bhowmick 《International journal of quantum chemistry》2024,124(1):e27288
We have investigated the potential energy curves (PECs) of the LiN heteronuclear diatomic molecule, including its ionic species LiN+ and LiN−, using explicitly correlated multi-reference configuration interaction (MRCI-F12) calculations in conjunction with the correlation consistent quintuple-𝜁 basis set. The effect of core–valence correlation, scalar relativistic effects, and the size of the basis sets has been investigated. A comprehensive set of spectroscopic constants determined based on the above-mentioned calculations are also reported for the lowest electronic states and all systems, including dissociation energies, harmonic and anharmonic vibrational frequencies, and rotational constants. Additional parameters, such as the dipole moments, equilibrium spin-orbit constants, excitation energies, and rovibrational energy levels, are also documented. We found that the three triplet states of LiN, namely, X 3∑−, A 3Π, and 2 3∑−, exhibit substantial potential wells in the PEC diagrams, while the quintet states are repulsive in nature. The ground state of the anion also shows a deep potential well in the vicinity of its equilibrium geometry. In contrast, the ground and excited states of the cation are very loosely bound. Charge transfer properties of each of these states are also analyzed to obtain an in-depth understanding of the interatomic interactions. We found that the core–valence correlation has a substantial effect on the calculated spectroscopic constants. 相似文献
136.
Saeed Shahrokhian Fatemeh Ghorbani-Bidkorbeh Ali Mohammadi Rasoul Dinarvand 《Journal of Solid State Electrochemistry》2012,16(4):1643-1650
A mixture of multi-walled carbon nanotube/graphite paste electrode modified with a salophen complex of cobalt was prepared
and was applied for the study of the electrochemical behavior of 6-mercaptopurine (MP) using cyclic and differential pulse
voltammetry (DPV). An excellent electrocatalytic activity toward the oxidation of MP was achieved, which led to a considerable
lowering in the anodic overpotential and remarkable increase in the response sensitivity in comparison with unmodified electrode.
Utilizing DPV method, a linear dynamic range of 1–100 μM with detection limit of 0.1 μM was obtained in phosphate buffer of
pH 3.0. The electrochemical detection system was very stable, and the reproducibility of the electrode response, based on
the six measurements during 1 month, was less than 3.0% for the slope of the calibration curves of MP. The electrochemical
method as a simple, sensitive, and selective method was developed for the determination of MP in pharmaceutical dosage form
and human plasma without any treatments. 相似文献
137.
Christopher T. Chantler Nicholas A. Rae M. Tauhidul Islam Stephen P. Best Joey Yeo Lucas F. Smale James Hester Narges Mohammadi Feng Wang 《Journal of synchrotron radiation》2012,19(2):145-158
Methods for the quantification of statistically valid measures of the uncertainties associated with X‐ray absorption fine structure (XAFS) data obtained from dilute solutions using fluorescence measurements are developed. Experimental data obtained from 10 mM solutions of the organometallic compound ferrocene, Fe(C5H5)2, are analysed within this framework and, following correction for various electronic and geometrical factors, give robust estimates of the standard errors of the individual measurements. The reliability of the refinement statistics of standard current XAFS structure approaches that do not include propagation of experimental uncertainties to assess subtle structural distortions is assessed in terms of refinements obtained for the staggered and eclipsed conformations of the C5H5 rings of ferrocene. Standard approaches (XFIT, IFEFFIT) give refinement statistics that appear to show strong, but opposite, preferences for the different conformations. Incorporation of experimental uncertainties into an IFEFFIT‐like analysis yield refinement statistics for the staggered and eclipsed forms of ferrocene which show a far more realistic preference for the eclipsed form which accurately reflects the reliability of the analysis. Moreover, the more strongly founded estimates of the refined parameter uncertainties allow more direct comparison with those obtained by other techniques. These XAFS‐based estimates of the bond distances have accuracies comparable with those obtained using single‐crystal diffraction techniques and are superior in terms of their use in comparisons of experimental and computed structures. 相似文献
138.
139.
S. M. Etesami M. Khatiri Yanehsari M. Mohammadi?Najafabadi 《International Journal of Theoretical Physics》2012,51(12):3694-3700
In this letter, we investigate the contributions which W boson helicity fractions in top quark decay receive from a two-Higgs doublet model, a top-color assisted technicolor (TC2) and the noncommutative extension of the Standard Model. It is shown that the deviations coming from these models are much less than the experimental sensitivity in measurement of the helicity fractions. 相似文献
140.
Amir H. Mohammadi Ali Eslamimanesh Veronica Belandria Dominique Richon Paramespri Naidoo Deresh Ramjugernath 《The Journal of chemical thermodynamics》2012
The application of semi-clathrate hydrate formation technology for gas separation purposes has gained much attention in recent years. Consequently, there is a demand for experimental data for relevant semi-clathrate hydrate phase equilibria. In this work, semi-clathrate hydrate dissociation conditions for the system comprising mixtures of {CO2 (0.151/0.399 mole fraction) + N2 (0.849/0.601 mole fraction) + 0.05, 0.15, and 0.30 mass fraction tetra-n-butylammonium bromide (TBAB)} aqueous solutions have been measured and are reported. An experimental apparatus which was designed and built in-house was used for the measurements using the isochoric pressure-search method. The range of conditions for the measurements was from 277.1 K to 293.2 K for temperature and pressures up to 16.21 MPa. The phase equilibrium data measured demonstrate the high hydrate promotion effects of TBAB aqueous solutions. 相似文献