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11.
The following organic and organic–inorganic hybrid compounds were prepared as photo-luminescent materials following efficient and practical synthetic methods: 1,3-bis[4-(n-alkoxy)phenyl]-2-propen-1-one (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10); 3,5-bis[4-(n-alkoxy)phenyl]-1H-pyrazole (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10) (in case of n = 7, a mixture of 3,5-bis(4-heptyloxyphenyl)-1H-pyrazole and 3,5-bis(4-heptyloxyphenyl)-4H-pyrazole was detected) and bis(3,5-bis [4-(n-alkoxy) phenyl]-1H-pyrazole) silver(I) nitrate (where, n-alkoxy: O(CH2)nH, n = 6,7,8,9 or 10). The prepared compounds have been characterised and their structures were elucidated depending upon (FTIR, UV-Vis, 1HNMR, 13CNMR, 2D 1H-1H-COSY, 2D 1H-13C-HSQC and mass spectra) in addition to molar conductivity measurements for silver(I) complexes. The mesomorphism behaviour of the prepared compounds was studied using polarised light optical microscopy and confirmed with differential scanning calorimetry and X-ray powder diffraction techniques. The studies showed that among all of these compounds only the pyrazole derivatives are liquid crystal materials. The luminescent properties of all the prepared compounds were also investigated which confirmed that all of these compounds are photo-luminescent in the crystalline solid state and in the mesophase.  相似文献   
12.
This work presents the applicability of applying a fuzzy logic approach to the calculation of noontime erythemal UV irradiance for the plain areas of Egypt. When different combinations of data sets were examined from the test performance point of view, it was found that 91% of the whole series was estimated within a deviation of less than +/-10 mW/m(2), and 9% of these deviations lay within the range of +/-15 mW/m(2) to +/-25 mW/m(2).  相似文献   
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Synthesis and Coordination of 2-Acetylimino-1,3-dimethylimidazoline. The Crystal Structure of [Cu4I4(C7H11N3O)2] 2-Acetylimino–1,3-dimethylimidazoline ( 2 , ImNAc) obtained from 1,3-dimethyl-2-iminoimidazoline ( 1 ) and acetyl chloride forms with CuI the stepped cubane type complex [Cu4I4(ImNAc)2] ( 3 ); the X-ray structure of 3 is reported.  相似文献   
14.
Electroluminescence associated with impact excitation or ionization of deep Cr(2+) impurity centers in bulk ZnSe is reported. A broad signal of mid-infrared luminescence between 2 and 3 microm is observed once the biased bulk ZnSe device runs into a nonlinear conduction regime. Optical powers in the nanowatt range have been measured at room temperature. The different mechanisms involved in this intracenter infrared light emission are discussed.  相似文献   
15.
Shock compression studies of pressed and confined ultrafine 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) powder were conducted using ultrashort ~300 ps, ~50 GPa shock waves. The recovered decomposition products were characterized using X-ray photoelectron spectroscopy, infrared spectroscopy, and Raman spectroscopy. A substantial amount of shock-related chemistry was observed. Approximately 75% of the nitrogen atoms were liberated as gas-phase species, along with ~33% of the oxygen atoms, as a result of the applied shock. Furthermore, we observe C 1s binding energies suggesting the formation of sp(3) hybridized amorphous carbon. For comparison, a carbon nitride material was also prepared and characterized by thermally pyrolizing TATB. The shock-compressed TATB and the thermally pyrolized TATB are qualitatively different, suggesting that, carbon nitrides, a possible indicator of nitrogen-rich heterocycles precursors, are not a major product class for strongly overdriven shock conditions. These experimental conditions were, however, not detonation conditions, and the possible formation of nitrogen-rich heterocycles in actual detonations still exists.  相似文献   
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Synthesis and Structure of [ImNCS2K] (ImN = 1,3-Dimethylimidazoline-2-imino): a Novel Potassium Dithiocarbiminate The reaction of the 2-iminoimidazoline 4 with KMe gives the potassium imidate 7 from which the potassium 1,1-dithiolate 8 is obtained in almost quantitative yield. Crystals of C6H8N3S2K · 1/6 CH3CN ( 8 · 1/6 CH3CN) are triclinic, space group P1 , Z = 6, a = 10.988(4), b = 13.597(8), c = 13.622(9) Å, α = 113.003, β = 105.53(3), γ = 105.62(3)°, V = 1636.90 Å3. The structure consists of a complicated 3-dimensional framework in which the K2 units bridged by the four sulfur atoms of two thiolate ligands are connected by nitrogen and sulfur bridges.  相似文献   
20.
The platinacyclopentane derivative [Cl(CH2)3R2P](Cl)PtPR2CH2CH2CH2 is formed by action of Cl(CH2)3PR2 on Pt(COD)2 in n-hexane via the not isolable Pt[PR2(CH2)3Cl]2 (R  C6H11) by oxidative addition of a CCl bond to platinum. [μ-CIRh(CO)2]2 reacts in benzene with Cl(CH2)3PR2 under partially CO substitution to give the stable intermediate Cl(OC)Rh[PR2(CH2)3Cl]2. In boiling toluene oxidative addition of a CCl bond to rhodium occurs under formation of the phospharhodacyclopentane [CI(CH2)3R2P] Cl2(OC)-RhPR2CH2CH2CH2 (R  C6H5). The 31P{1H}-NMR spectra of the rhodium compound is characterized by an ABX system, that of the platinum by superposition of an ABX pattern with an AB spectrum.  相似文献   
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