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1.
2.
P. I. Kazaryan S. V. Avakyan A. A. Gevorkyan R. G. Kulinkovich G. A. Panosyan 《Chemistry of Heterocyclic Compounds》1983,19(12):1267-1273
A series of derivatives of 4,4-dimethyl-5-methylene-1,3-dioxolane has been synthesized, and their reaction with dichlorocarbene, obtained under interphase catalysis conditions, has been studied. The adducts obtained undergo thermal isomerization into dichloroethylidene derivatives. 相似文献
3.
V. G. Avakyan N. A. Kubasova É. Kh. Kurasheva I. A. Musaev 《Russian Chemical Bulletin》1992,41(9):1628-1634
The conformations and heats of formation of all trans(T)- and cis(C)-2- and 3-methyl-substituted T- and Cbicyclo[4.4.0]decanes (BD) were calculated by the MM2 method of molecular mechanics. It was shown that the conformationally mobile T-2-Me-CBD and T-3-Me-CBD can exist in normal conditions as an inseparable mixture of conformers with a different equatorial or axial orientation of the Me groups. The Raman scattering (RS) spectra of TBD and CBD were investigated. RS bands whose frequencies were sensitive to the type of ring linkage and orientation (but not the position) of the Me substituents were detected in the 700–300 cm–1 region.A. V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 117912 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 2089–2097, September, 1992. 相似文献
4.
G. A. Korneeva N. N. Ezhova E. V. Slivinskii V. G. Avakyan S. M. Loktev 《Russian Chemical Bulletin》1989,38(12):2444-2447
N,N-Dimethylacetamide and N, N-dimethyformamide react with RhCl(PPh3)3 with displacement of PPh3 and the formation of a complex with the amide. Formamide and N-propylacetamide do not form similar complexes under similar conditions. In contrast to the reaction of RhCl(PPh3)3, which leads to the formation of RhCl(CO)(PPh3)2 due to decarbonylation of CH2O, stabilization of the 2-CH2O form of the CH2O coordinated with rhodium is likely in the reaction of formaldehyde with a rhodium complex containing an N-bonded amide. Under the conditions of hydroformylation of CH2O in a solution of the Wilkinson complex in an unsubstituted amide the dominating pathway of the transformation of formaldehyde is its reaction with the solvent or the ammonia formed via decarbonylation of the unsubstituted amide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2670–2673, December, 1989. 相似文献
5.
A. A. Gevorkyan P. I. Kazaryan S. V. Avakyan G. A. Panosyan 《Chemistry of Heterocyclic Compounds》1981,17(7):642-644
The reaction of 1-bromo(or chloro)-3-methyl-2,3-epoxybutane with alcohols in the presence of the alkali metal alkoxides leads to the formation of epoxy ethers by direct replacement of the halogen atoms without participation of the epoxide ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 878–880, July, 1981. 相似文献
6.
A. K. Avakyan I. N. Zavestovskaya T. K. Lobzhanidze S. A. Polikhov V. P. Smirnov 《Bulletin of the Lebedev Physics Institute》2018,45(11):356-359
Main parameters of digital flat panel detectors, to be taken into account in developing imaging systems are considered. Various factors affecting obtained images are presented. Experimental results presented confirm the necessity of image correction. 相似文献
7.
N.A. Tarasenko V.V. Volkova V.G. Zaikin A.I. Mikaya A.A. Tishenkov V.G. Avakyan L.E. Guselnikov M.G. Voronkov S.V. Kirpichenko E.N. Suslova 《Journal of organometallic chemistry》1985,288(1):27-33
The dissociative ionization of 4,4-dimethyl-1-thia-4-silacyclohexane (I) and 2,3,3-trimethyl-1-thia-3-silacyclopentane(II) has been studied by electron photoionization (PI) mass spectrometric methods. The molecular ion fragmentation is mainly related to the loss of ethylene and results in a [Me2SiSC2H4]+? (m/z 118) ion-radical (A). Further loss of ethylene from A produces a dimethylsilanethione [Me2SiS]+? (m/z 90) ion-radical (B). The latter is the most abundant ion in the mass spectra of I and II at 70 eV.The ionization energies (IE) of I (8.22 ± 0.07 eV) and II (8.06 ± 0.03 eV) and the appearance energies (AE) of ion-radicals A and B have been determined. Also, the following heats of formation were calculated (kJ/mol): ΔHf0(I) = ?31.1; ΔHf0(II) = ?65.8; ΔHf0(MI+?) = 762.0; ΔHf0(MII+?)= 712.1; ΔHf0(A)aver = 780.2; ΔHf0(B)aver = 847.7. 相似文献
8.
V. G. Avakyan L. E. Gusel’nikov S. L. Gusel’nikov V. F. Sidorkin 《Russian Chemical Bulletin》2005,54(9):2013-2022
The effect of the nature of substituents at sp2-hybridized silicon atom in the R2Si=CH2 (R = SiH3, H, Me, OH, Cl, F) molecules on the structure and energy characteristics of complexes of these molecules with ammonia, trimethylamine,
and tetrahydrofuran was studied by the ab initio (MP4/6-311G(d)//MP2/6-31G(d)+ZPE) method. As the electronegativity, χ, of the substituent R increases, the coordination bond
energies, D(Si← N(O)), increase from 4.7 to 25.9 kcal mol−1 for the complexes of R2Si=CH2 with NH3, from 10.6 to 37.1 kcal mol−1 for the complexes with Me3N, and from 5.0 to 22.2 kcal mol−1 for the complexes with THF. The n-donor ability changes as follows: THF ≤ NH3 < Me3N. The calculated barrier to hindered internal rotation about the silicon—carbon double bond was used as a measure of the
Si=C π-bond energy. As χ increases, the rotational barriers decrease from 18.9 to 5.2 kcal mol−1 for the complexes with NH3 and from 16.9 to 5.7 kcal mol−1 for the complexes with Me3N. The lowering of rotational barriers occurs in parallel to the decrease in D
π(Si=C) we have established earlier for free silenes. On the average, the D
π(Si=C) energy decreases by ∼25 kcal mol−1 for NH3· R2Si=CH2 and Me3N·R2Si=CH2. The D(Si←N) values for the R2Si=CH2· 2Me3N complexes are 11.4 (R = H) and 24.3 kcal mol−1 (R = F). sp2-Hybridized silicon atom can form transannular coordination bonds in 1,1-bis[N-(dimethylamino)acetimidato]silene (6). The open form (I) of molecule 6 is 35.1 and 43.5 kcal mol−1 less stable than the cyclic (II, one transannular Si←N bond) and bicyclic (III, two transannular Si←N bonds) forms of this molecule, respectively. The D(Si←N) energy for structure III was estimated at 21.8 kcal mol−1.
Dedicated to Academician N. S. Zefirov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1952–1961, September, 2005. 相似文献
9.
Conclusions The vibrational spectra of crystalline ethylenedinitramine, ethylenedinitramine labeled with N15, as well as their deutero-derivatives were studied. Assignment of the vibration frequencies of the nitramine fragment is proposed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2194–2197, October, 1969.The authors would like to thank B. Lokshin for recording the IR spectra in this region, as well as A. Bobrov for recording the Raman spectra. 相似文献
10.
V. B. Nazarov V. G. Avakyan T. G. Vershinnikova M. V. Alfimov 《Russian Chemical Bulletin》2000,49(10):1699-1706
Fluorescence of the inclusion complexes with different compositions formed by naphthalene-h8, naphthalene-d8, 2,7-dimethylnaphthalene (DMN), and 2-benzylnaphthalene (BN) with β-cyclodextrin (β-CD) in water was studied. Two types of fluorescence are observed, monomer (MF) and excimer (EF_ fluorescence. The excimer fluorescence of the 2∶2 complex emitted by aggregated light-dispersing crystals forming a precipitate, whereas is the MF is concentrations, EF predominates for the resulting complexes. A proposed structure of the inclusion complexes was derived from MNDO/PM3 semiempirical quantum-chemical calculations. The EF is caused by the structure of the complex, in which both naphthalene molecules are separated by a distance of 4.7 Å: they lie in parallel orientation to each other, whereby one ring is displaced from the other by one-fourth of the length of the naphthalene ring. The complexes of 2,7-DMN and 2-benzylnaphthalene with β-CD do not exhibit EF. For the 2∶2 complex of 2,7-DMN with β-CD, this is due to the fact that the aromatic fragments are removed too far from one another 2-Benzylnaphthalene is unable to form an inclusion complex with β-CD, in whose structure the aromatic fragments inside the cavity could be arranged in parallel planes; instead, it forms a 1∶2 complex with β-CD. 相似文献