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11.
Budruev A. V. Giricheva M. A. Davydov D. A. Pokrovskaia A. V. Pronina A. L. 《Russian Journal of General Chemistry》2021,91(8):1448-1452
Russian Journal of General Chemistry - Methyl 12-oxo-6,12-dihydroazepino[2,1-b]quinazoline-8-carboxylate and methyl 3H-azepin-2(1H)-one-5-carboxylate were synthesized by photoinduced... 相似文献
12.
The potential energy surface of the LaI3 molecule is scanned along the normal coordinate by a B3LYP/SDD, SDD method. It is shown that a nonplanar ν2(A 2″) vibrational potential function is most anharmonic. The effect of anharmonicity on the root mean square amplitudes of vibrations and the vibrational molecule spectrum is stated. 相似文献
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N. I. Giricheva G. V. Girichev S. A. Shlykov O. V. Pelipets 《Journal of Structural Chemistry》2000,41(2):231-237
A simultaneous electron diffraction and mass spectrometric experiment was performed to investigate erbium trichloride vapor at 1134(20) K. The vapor contains 97(2) mol.% monomer and 3(2) mol.% dimer. For the ErCl3 molecule, the following parameters were found: rg(Er-Cl) 2.430(5) å, rg(Cl-Cl) 4.036(19) å, effective angle CIErCl 112.3(1.2)?; with vibrational corrections included, these values correspond to the pyramidal equilibrium configuration of the molecule. For the dimer, a stmcture of D2h, symmetry with four bridging bonds was adopted and the following parameters were found: rg(Er-Cl1) 2.444(5) å, rg(Er-Clh) 2.65(4) å, ∠Cl1-Er-Cl1 117(5)°, ∠Clb-Er-Clb 84(10)°. 相似文献
15.
G. V. Girichev N. I. Giricheva N. V. Tverdova A. O. Simakov N. P. Kuz’mina O. V. Kotova 《Journal of Structural Chemistry》2010,51(2):223-230
Gas electron diffraction at a temperature T of 641(5) K is used to study the structure of an N,N′-ethylenebis(salicylaldiminato) zinc(II) molecule, ZnO2N2C16H14, further Zn(salen). The structure of a gaseous Zn(salen) complex has C 2 symmetry and is characterized by a substantial turn of two chelating fragments of the ligand with respect to each other, and also by a big difference in the length of coordination bonds: r h1(Zn-O)=1.902(7) Å r h1(Zn-N)= 2.027(7) Å. Results of the DFT/B3LYP calculation with 6-31G* and CEP,TZV basis sets of the molecule structure well agree with the experimental data. The electronic structure of Ni(salen), Cu(salen), Zn(salen), and Zn(acacen) molecules is considered. 相似文献
16.
Nina I. Giricheva Georgiy V. Girichev Yulia S. Medvedeva Sergey N. Ivanov Anna V. Bardina Vyacheslav M. Petrov 《Structural chemistry》2011,22(2):373-383
A combined gas-phase electron diffraction and quantum chemical (B3LYP/6-311+G**, B3LYP/cc-pvtz, MP2/cc-pvtz) study of molecular
structure of 2-nitrobenzenesulfonamide (2-NBSA) was carried out. Quantum chemical calculations showed that 2-NBSA has four
conformers, two of which are stabilized by intramolecular hydrogen bond. The latter (with the S–N bond in a close to orthogonal
position around the phenyl ring and differing from each other by staggered or eclipsed positions of the N–H and S=O bonds
in the SO2NH2 group) presented in a saturated vapor over 2-NBSA at T = 433 (3) K in commensurable amounts. Experimental internuclear distances (Ǻ) for the staggered conformer are (?): r
h1(C–H)av. = 1.071(9), r
h1(C–C)av. = 1.390(4), r
h1(C–S) = 1.789(8), r
h1(S=O)av. = 1.427(6), r
h1(S–N) = 1.644(6), r
h1(N–O)av. = 1.221(4), r
h1(C′–N) = 1.487(8), r
h1(N–H)av. = 1.014. Calculations at B3LYP/cc-pvtz level were performed to determine the structure and the energies of the transition
states between conformers. It was shown that the conformer structures of free molecule differ from those of a molecule stabilized
by intermolecular hydrogen bonds in a crystal. Influence of a substituent X (X = –CH3, –NO2) on conformational features of the ortho-substituted benzenesulfonamide was established. 相似文献
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19.
G. V. Girichev S. A. Shlykov N. I. Giricheva A. V. Krasnov I. O. Zyabko N. P. Kuz’mina I. G. Zaitseva 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(4):524-527
The sublimation of erbium tris-hexafluoroacetylacetonate Er(C5O2HF6)3 was studied by the Knudsen effusion method with the mass spectrometric determination of vapor composition. Groups of ions containing one, two, and three metal atoms were recorded. The enthalpies of sublimation of the monomeric, dimeric, and trimeric forms ΔS H°(362 K) were found to be 133 ± 4, 135 ± 7, and 139 ± 38 kJ/mol, respectively. The melting point of Er(C5O2HF6)3 was 390 ± 2 K. No oligomeric forms were observed in vapor superheated above 430 K. 相似文献
20.
E. V. Antina N. V. Belova M. B. Berezin G. V. Girichev N. I. Giricheva A. V. Zakharov A. A. Petrova S. A. Shlykov 《Journal of Structural Chemistry》2009,50(6):1035-1045
The molecular structure of zinc acetylacetonate was studied in a simultaneous electron diffraction and mass spectrometric experiment at 376(7) K and by quantum-chemical calculations. The Zn(acac)2 molecule has a structure of D 2d symmetry with the chelate rings lying in mutually perpendicular planes. The main geometrical parameters of the molecule are r h1(Zn-O) = 1.942(4) Å, r h1(C-O) = 1.279(3) Å, r h1(C-Cr) = 1.398(3) Å, r h1(C-C m ) = 1.504(5) Å, ∠(O-Zn-O) = 93.2(7)°, ∠(Zn-O-C) = 125.9(7)°, ∠(C-Cr-C) = 125.8(14)°, ∠(O-C-C m ) = 115.2(9)°. The effective rotation angle of methyl groups is close to 30°, which is indicative of the free rotation of these groups. The vibration frequencies were obtained by quantumchemical calculations, and the IR spectrum of the Zn(acac)2 molecule was interpreted. 相似文献