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41.
O. N. Chugai A. S. Gerasimenko V. K. Komar’ D. S. Morozov S. V. Oleinik V. M. Puzikov I. M. Rizak S. V. Sulima 《Physics of the Solid State》2010,52(12):2467-2471
The frequency and temperature dependences of the real and imaginary parts of the permittivity of ZnSe crystals grown from
melt have been measured in the low-frequency range. It has been found that the crystal samples cut from different parts of
the ingot exhibit different properties depending on their distance from the ingot origin. The difference in the properties
is explained by the dominant influence exerted on the polarization by point defects, the formation of which is associated
with the deviation of the composition from stoichiometry, as well as by residual impurities and stresses in the crystals. 相似文献
42.
Abstract The non-monotonic distribution of secondary defects after two-step annealing of silicon implanted with boron ions is investigated using the TEM technique and the method of mercury probe along a bevel which was made chemically. Possible mechanisms of multilayer structure formation are discussed. 相似文献
43.
We analyze the behavior of the discharge in a coaxial plasma jet accelerator with a pulsed supply of the working gas released by an electric discharge from titanium hydride powder. Radiation (varying with time) from the discharge in the accelerator was detected using an optical method through a narrow slit cut along the outer electrode by a Bifo Company K008 streak camera. Stable operation of the source with the highest kinetic energy of a pure hydrogen plasma jet was attained for a relatively uniform glow of the discharge along the accelerator during the entire current pulse. Conversely, local glow of the discharge at the outlet or inlet of the accelerator considerably contaminated the discharge with impurities, and the kinetic energy of the plasma jet decreased by an order of magnitude. The highest energy of the plasma jet was attained when the polarity of the electrodes was the same as at the plasma focus. 相似文献
44.
A. V. Gerasimenko M. A. Pushilin R. L. Davidovich 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(11):m358-m361
The title compounds, (C2H6NO2)2[NbOF5], (I), and (C3H8NO2)2[NbOF5]·2H2O, (II), are built from isolated distorted octahedral [NbOF5]2− complex anions, amino acid cations and water molecules [for (II)]. In the pentafluoridooxidoniobate(V) anions, the Nb and O atoms, and the F atoms in trans positions with respect to the O atoms, are disordered about an inversion centre for both structures. The Nb atoms are shifted from the inversion centres by distances of 0.1455 (1) and 0.1263 (2) Å for (I) and (II), respectively. The Nb=O and Nb—F(trans) bond lengths are 1.7952 (3) and 2.0862 (3) Å, respectively, for (I), and 1.8037 (7) and 2.0556 (7) Å for (II). In the crystal structures, cations and water molecules [for (II)] are linked to the [NbOF5]2− anions via hydrogen bonds. This study demonstrates the possibility of true geometry determination of disordered [NbOF5]2− complex anions in centrosymmetric structures. 相似文献
45.
A. V. Ivanov I. A. Lutsenko M. A. Ivanov A. V. Gerasimenko O. N. Antzutkin 《Russian Journal of Coordination Chemistry》2008,34(8):584-593
Platinum(II) O,O′-dicyclohexyl dithiophosphate [Pt{S2P(O-cyclo-C6H11)2}2] (I) and platinum(II) O,O′-diisopropyl dithiophosphate [Pt{S2P(O-iso-C3H7)2}2] (II) complexes were obtained and studied by solidstate 13C, 31P, and 195Pt CP/MAS NMR spectroscopy. The dithiophosphate (Dtph) ligands in molecular structure I were found to be coordinated by platinum in S,S′-bidentate fashion to form the planar chromophore [PtS4] (single-crystal X-ray diffraction data). For complex II, a new α-form (α-II) was obtained and identified by 31P MAS NMR spectroscopy. The 31P chemical shift anisotropy δaniso and the asymmetry parameter η of the 31P chemical shift tensor were calculated from the whole MAS spectra. 相似文献
46.
A. V. Gerasimenko A. V. Polishchuk L. M. Volkova E. T. Karaseva V. E. Karasev 《Russian Journal of Coordination Chemistry》2008,34(1):8-13
Nalidixium tetrachloroantimonate monohydrate, (C12H13N2O3)SbCl4 · H2O, has been synthesized and its crystal structure has been determined. The structure is built of the [Sb2Cl8]2? anions, C12H13N2O 3 + nalidixium cations, and H2O molecules joint by hydrogen bonds and π-π-and Cl?Cl interactions. The [Sb2Cl8]2? anion is a dimer of the SbCl5 E distorted octahedra sharing common Cl?Cl edge (E is the lone electron pair). The Sb polyhedra contain two short Sb-Cl bonds (2.387 and 2.395 Å), one bond of a medium length (2.508 Å), and two long bridging bonds (2.745 and 3.054 Å). 相似文献
47.
E. I. Voit N. A. Didenko K. A. Gayvoronskaya A. V. Gerasimenko 《Optics and Spectroscopy》2016,121(2):229-240
Fluoridezirconate crystallohydrates ZnZrF6 · nH2O (n = 6–2) and anhydrous ZnZrF6 are investigated by vibrational spectroscopy and thermography. The influence of the hydrate number on the structure of the cationic and anionic sublattices of the crystallohydrates is studied. The changes in the strength of HOH···F and HOH···O hydrogen bonds of coordinated and outer-sphere water molecules occurring with variations in the hydrate number are determined by changes in the IR spectra. The IR spectra of ZnZrF6 · nH2O (n =6, 4) compounds, which have isolated complex anions [ZrF6]2– in their structure, revealed a band with two peaks in the range of 3470–3430 cm–1, which corresponds to stretching vibrations of coordinated water molecules. The spectra of ZnZrF6 · nH2O (n = 5, 3, 2, 1) crystallohydrates with a polymeric structure show a high-frequency shift of this band, which corresponds to weakening of hydrogen bonds. The vibrations of crystallization water molecules involved in the network of strong O–H···F and O–H···O hydrogen bonds manifest themselves in the spectra of ZnZrF6 · nH2O (n =5, 3) crystallohydrates by broad structureless bands in the region of stretching, bending, and libration vibrations. 相似文献
48.
A. V. Ivanov S. A. Zinkin A. V. Gerasimenko O. N. Antzutkin W. Forsling 《Russian Journal of Coordination Chemistry》2007,33(1):20-31
Silver(I) complexes with four symmetrically substituted O,O′-dialkyl derivatives of dithiophosphoric acid of the general formula [Ag{S2P(OR)2}] n (R = C2H5, i-C3H7, C4H9, and s-C4H9) were obtained. Their structures and spectroscopic characteristics were studied by solid-state 13C and 31P CP/MAS NMR spectroscopy and X-ray diffraction analysis. The parameters of the anisotropy of the 31P chemical shift 31P-δ aniso and η (δ aniso is the chemical shift anisotropy and η is the asymmetry parameter) calculated from the diagrams of the x 2-statistic revealed that the (RO)2PS2 groups act as bridging ligands in all the silver(I) complexes obtained. The hexanuclear complex [Ag6{S2P(O-i-C3H7)2}6] was found to form two modifications α and β. According to the X-ray diffraction data, the silver(I) complex with O,O′-di-s-butyl dithiophosphate exists as discrete hexanuclear molecules [Ag6{S2P(O-s-C4H9)2}6]. In the clear molecules β-[Ag6{S2P(O-i-C3H7)2}6], the signals for the phosphorus atoms were assigned to their positions determined from the X-ray diffraction data. 相似文献
49.
A. V. Ivanov I. A. Lutsenko A. S. Zaeva A. V. Gerasimenko E. B. Merkulov S. A. Leskova 《Russian Journal of Coordination Chemistry》2007,33(11):815-825
A supramolecular compound of the general formula [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]4 · NH(CH2)4O · C2H4{N(CH2)4O}2 (I) was obtained and examined by X-ray diffraction analysis and thermography. According to X-ray diffraction data, the crystal lattice of compound I shows an unusual alternation of two independent centrosymmetric supramolecular complexes [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]2 · C2H4{N(CH2)4O}2 (Ia) and [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]2 · NH(CH2)4O (Ib). Either complex includes two molecules of an adduct of bis(diethyldithiocarbamato)zinc with morpholine and outer-sphere molecules of 1,2-dimorpholinoethane or morpholine. Adduct molecules are structurally nonequivalent in pairs and linked with solvate molecules by hydrogen bonds. The calculated geometries of the zinc polyhedra are intermediate between trigonal bipyramid and tetragonal pyramid. Thermal decomposition of supramolecular compound I proceeds through desorption of the outer-sphere and coordinated organic molecules; in the final step, defragmentation of the dithiocarbamate part gives zinc sulfide. 相似文献
50.
A. V. Gerasimenko V. Ya. Kavun N. A. Didenko A. B. Slobodyuk N. F. Uvarov V. I. Sergienko 《Russian Journal of Inorganic Chemistry》2007,52(5):713-726
Rubidium ammonium hexafluorozirconates Rb2?x (NH4)x ZrF6 (1.5 < x < 2.0) have been synthesized, and their structure, ion mobility (180–480 K), and electrophysical properties have been studied by X-ray crystallography, 1H and 19F NMR, DTA, and impedance methods. Compounds with x > 1.5 are isostructural with (NH4)2ZrF6. Rubidium cations are isomorphously substituted for the ammonium cations. The high-temperature modifications of the compounds, which form upon the phase transitions at 413–418 K, are characterized by translational diffusion of ions in the fluoride and ammonium sublattices. The 19F NMR spectra are characterized by uniaxial 19F magnetic shift anisotropy. The electrophysical properties of this series of compounds are studied in the temperature range 300–480 K. 相似文献