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1.
The standard activity threshold-based method (the "top X" approach), currently widely used in the high-throughput screening (HTS) data analysis, is ineffective at identifying good-quality hits. We have proposed a novel knowledge-based statistical approach, driven by the hidden structure-activity relationship (SAR) within a screening library, for primary hit selection. Application to an in-house ultrahigh-throughput screening (uHTS) campaign has demonstrated it can directly identify active scaffolds containing valuable SAR information with a greatly improved confirmation rate compared to the standard "top X" method (from 55% to 85%). This approach may help produce high-quality leads and expedite the hit-to-lead process in drug discovery. 相似文献
2.
H.M. Asatryan 《Physics letters. [Part B]》1982,117(5):309-311
The possibility of introducing the discrete symmetry D is studied, which along with SUc(3) × SUL(2) × U(1)-symmetry, remains after the breaking of SO(N) grand unified symmetry by the Higgs fields vevs ~ 1015 GeV. The D quantum number distinguishes the fermions coupled with W-bosons via left and right currents. As a result, the presence of low-mass fermions in the theory is provided. 相似文献
3.
4.
In manganese-doped PbWO4 crystals, low-intensity signals of triclinic clusters Mn4+-V O and Fe3+-V Pb have been revealed in addition to signals of Mn2+ tetragonal centers. The Mn4+-V O cluster is formed by a Mn4+ ion in the W6+ position, which is associated with a vacancy of the nearest neighbor O2?ion, and the Fe3+-V Pb cluster consists of a Fe3+ ion substituting for Pb2+ with a local compensation of by a lead vacancy. It has been shown that, in PbWO4: Mn, there is also a small amount of Mn4+ tetragonal centers located in the Pb2+ position with a nonlocal compensation of an excess charge. 相似文献
5.
A new computational approach to the edge-detection problem, based on the continuous extension of discrete cosine transform
(CEDCT) technique is proposed. This technique has some attractive properties, and other things being equal, it has more precise
results than the usual discrete Fourier or discrete cosine transforms, especially at the intermediate points. That is why
this technique allows one to estimate numerically a finite number of a derivatives of a discrete set of multidimensional points,
using some specified properties of CEDCT. Because of using the spectrum of a given set of points, this approach is applicable
to a wide area of signal-and image-processing problems. The results obtained by the proposed approach are compared with the
well-known and widely used Canny algorithm. Some 1D and 2D numerical examples are given.
The text was submitted by the authors in English. 相似文献
6.
Computational quantum theory is employed to determine the thermochemical properties of n-alkyl nitro and nitrite compounds: methyl and ethyl nitrites, CH3ONO and C2H5ONO, plus nitromethane and nitroethane, CH3NO2 and C2H5NO2, at 298.15 K using multilevel G3, CBS-QB3, and CBS-APNO composite methods employing both atomization and isodesmic reaction analysis. Structures and enthalpies of the corresponding aci-tautomers are also determined. The enthalpies of formation for the most stable conformers of methyl and ethyl nitrites at 298 K are determined to be -15.64 +/- 0.10 kcal mol-1 (-65.44 +/- 0.42 kJ mol-1) and -23.58 +/- 0.12 kcal mol-1 (-98.32 +/- 0.58 kJ mol-1), respectively. DeltafHo(298 K) of nitroalkanes are correspondingly evaluated at -17.67 +/- 0.27 kcal mol-1 (-74.1 +/- 1.12 kJ mol-1) and -25.06 +/- 0.07 kcal mol-1 (-121.2 +/- 0.29 kJ mol-1) for CH3NO2 and C2H5NO2. Enthalpies of formation for the aci-tautomers are calculated as -3.45 +/- 0.44 kcal mol-1 (-14.43 +/- 0.11 kJ mol-1) for aci-nitromethane and -14.25 +/- 0.44 kcal mol-1 (-59.95 +/- 1.84 kJ mol-1) for the aci-nitroethane isomers, respectively. Data are evaluated against experimental and computational values in the literature with recommendations. A set of thermal correction parameters to atomic (H, C, N, O) enthalpies at 0 K is developed, to enable a direct calculation of species enthalpy of formation at 298.15 K, using atomization reaction and computation outputs. 相似文献
7.
Edinach E. V. Uspenskaya Yu. A. Gurin A. S. Babunts R. A. Asatryan G. R. Romanov N. G. Badalyan A. G. Baranov P. G. 《Physics of the Solid State》2019,61(10):1820-1828
Physics of the Solid State - Electron paramagnetic resonance (EPR) spectra of Ce3+, Yb3+, Cr3+, and Gd3+ impurity ions in yttrium aluminum garnet Y3Al5O12 (YAG) ceramics were detected and... 相似文献
8.
V. A. Vazhenin A. P. Potapov G. R. Asatryan A. G. Petrosyan K. L. Ovanesyan A. V. Fokin 《Physics of the Solid State》2017,59(9):1812-1817
The ESR spectrum of Gd3+ and Eu2+ monoclinic centers, which substitute for yttrium ions in YAlO3 crystals doped with europium and zirconium, has been investigated. Parameters of the fine structure of these centers are determined. The hyperfine-interaction parameters are determined for the centers with 151Eu isotope, and the hyperfine structure of the centers with 153Eu isotope is discussed. 相似文献
9.
G. R. Asatryan V. S. Vikhnin T. I. Maksimova M. Maczka K. Hermanowicz J. Hanuza 《Physics of the Solid State》2006,48(6):1099-1101
Crystals of a proper ferroelastic K3Na(CrO4)2 containing molecular impurity ions MnO 4 2? are studied using electron paramagnetic resonance (EPR) and optical spectroscopy. The EPR spectrum of the Mn6+ ion contained in the molecular impurity ion MnO 4 2? is identified at low temperatures (T ≤ 20 K). The intensity of this spectrum decreases unusually fast as the temperature increases. A broad IR luminescence band with a vibronic structure well resolved at a temperature of 8 K is revealed. Theoretical treatment of the Mn6+ ion involved in the molecular impurity ions MnO 4 2? of the K3Na(CrO4)2 ferroelastic crystal suggests that an important role in this case is played by the pseudo-Jahn-Teller. The pseudo-Jahn-Teller effect offers an explanation for the appearance of a fine structure in the vibronic replicas in the luminescence spectrum, on the one hand, and accounts for the fast decrease in the intensity of the EPR spectrum of K3Na(CrO4)2: MnO 4 2? with increasing temperature, on the other. 相似文献
10.
Vazhenin V. A. Potapov A. P. Petrosyan A. G. Asatryan G. R. Fokin A. V. Artyomov M. Yu. 《Physics of the Solid State》2019,61(6):1067-1073
Physics of the Solid State - In crystals of yttrium orthoaluminate doped with the 151Eu isotope, Eu2+, Cr3+, Gd3+, and Мо3+ paramagnetic centers are detected. The fine structure... 相似文献