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1.
In solvents of different polarities, the lactam-lactim tautomeric equilibrium of isoxazoli-din-3-one is strongly displaced in the direction of the lactam. The lactim form cannot be detected. It has been concluded that there is no connection between the dual chemical behavior of isoxazolidin-3-one and its potassium salt in the alkylation reaction with the equilibrium isomerization of these compounds. It has been shown that the mechanism of alkylation is connected with the structure of the lactam anion. Evidence is given in favor of a mesomeric structure of the anion with the main charge on the nitrogen at which substitution chiefly takes place.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 898–901, July, 1973. 相似文献
2.
V. A. Kovtunenko T. T. Dobrenko Z. V. Voitenko A. K. Tyltin F. S. Babichev 《Chemistry of Heterocyclic Compounds》1984,20(9):978-983
The previously unknown 1-ethylthio-2R-isoindoles have been obtained by modifying the corresponding isoindol-1-ones. The reaction of these isoindoles with N-arylmaleimide derivatives has been investigated. A rare case of nonsynchronous addition in the Diels-Alder reaction has been found.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1200–1205, September, 1984. 相似文献
3.
Volodymyr O. Knizhnikov Zoia V. Voitenko Vladimir B. Golovko Marian V. Gorichko 《Tetrahedron: Asymmetry》2012,23(14):1080-1083
A novel regio- and diastereospecific ring cleavage of bornane-2,3-dione (camphor quinone) under Bucherer-Bergs reaction conditions has been investigated. The simplicity of this transformation provides a novel and straightforward synthetic pathway to enantiopure derivatives of cyclopentane carboxylic acid as well as functionalized hydantoins in just two steps, starting from inexpensive and easily available camphor. 相似文献
4.
R. V. Rodik V. Yu. Malytskyi V. S. Starova T. V. Yegorova A. I. Kysil O. A. Zaporozhets Z. V. Voitenko V. I. Kalchenko 《Journal of inclusion phenomena and macrocyclic chemistry》2013,77(1-4):343-350
New derivatives of calix[4]arenes, containing two isoindole fragments in distal positions of the macrocycle upper rim were synthesized. According to NMR and molecular modeling data, the obtained calixarenes exist in “flattened cone” conformation with inclination angles of benzene rings to the macrocycle plane equal to 133–140° and 92–100°. Fluorometric studies showed the presence of self-aggregation of isoindolenylcalixarenes in acetone solutions starting from micromolar concentrations. 相似文献
5.
Serhii Krykun Maksym Dekhtiarenko David Canevet Vincent Carr Frdric Aubriet Eric Levillain Magali Allain Zoia Voitenko Marc Sall Sbastien Goeb 《Angewandte Chemie (International ed. in English)》2020,59(2):716-720
Developing methodologies for on‐demand control of the release of a molecular guest requires the rational design of stimuli‐responsive hosts with functional cavities. While a substantial number of responsive metallacages have already been described, the case of coordination‐tweezers has been less explored. Herein, we report the first example of a redox‐triggered guest release from a metalla‐assembled tweezer. This tweezer incorporates two redox‐active panels constructed from the electron‐rich 9‐(1,3‐dithiol‐2‐ylidene)fluorene unit that are facing each other. It dimerizes spontaneously in solution and the resulting interpenetrated supramolecular structure can dissociate in the presence of an electron‐poor planar unit, forming a 1:1 host–guest complex. This complex dissociates upon tweezer oxidation/dimerization, offering an original redox‐triggered molecular delivery pathway. 相似文献
6.
The differential tunnel conductance G S of the junction between a normal metal and a superconductor with a charge density wave (CDW) is calculated as a function of the voltage V across the junction. The results are averaged over the spread of superconducting and CDW energy gaps in the nanoscale-inhomogeneous superconductor. It is shown that, if both order parameters are nonzero, a dip-hump structure is formed beyond the superconducting gap of G S (V). If the phase of the CDW order parameter is not equal to π/2, a dip-hump structure will appear solely or mainly for one sign of the bias polarity. The results agree with the experimental data for Bi2Sr2CaCu2O8+δ and other high-temperature oxides 相似文献
7.
V. K. Duplyakin O. N. Baklanova O. A. Chirkova N. V. Antonicheva A. B. Arbuzov N. N. Voitenko V. A. Drozdov V. A. Likholobov 《Kinetics and Catalysis》2010,51(1):126-130
The interaction of nickel hydroxocarbonate, ammonium paramolybdate, and ammonium metatungstate (Ni: Mo: W = 3: 1: 1) is reported.
Under mechanical activation conditions, nickel hydroxocarbonate particles undergo comminution and ammonium paramolybdate and
ammonium metatungstate particles soften and aggregate. It is demonstrated by DTA, X-ray diffraction, and IR spectroscopy that
heat treatment of the mechanically activated mixture at 400–450°C yields the salts NiMoO4 and NiWO4. 相似文献
8.
A. E. Voitenko 《Journal of Applied Mechanics and Technical Physics》1990,31(2):273-275
Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 2, pp. 118–120, March–April, 1990. 相似文献
9.
10.
Zoia V. Voitenko Oleksandr I. Halaev Sergey V. Kolotilov Christine Lepetit Bruno Donnadieu Remi Chauvin 《Tetrahedron》2010,66(41):8214-8222
Base- and acid-catalyzed nucleophilic addition of 11H-isoindolo[2,1-a]quinazoline-5-one to aromatic aldehydes and maleimides was investigated. The aldol adducts and condensation products were obtained stereoselectively. Main diastereomers of the Michael adducts were isolated in 74-89% yield, and converted by N-methylation to new stable α-substituted isoindole derivatives, for which 6-methylisoindolo[2,1-a]]quinazoline-5-one stands as the unsubstituted reference. The stability of the latter was monitored in moist aerated CDCl3 solution, and one of the oxidative hydrolysis product was characterized by X-ray diffraction analysis as the corresponding N-arylphthalimide. The reactivity of the unsubstituted 6-methylisoindolo[2,1-a]]quinazoline-5-one was also investigated with acetylenic Michael acceptors. Fully conjugated isoindole derivatives possessing an original pull-push-pull structure were obtained. The conformations and molecular orbitals of the dibenzoylacetylene adduct were studied at the DFT level of theory. Its static quadratic hyperpolarizabilty β0 was also calculated at the ZINDO level. 相似文献