排序方式: 共有41条查询结果,搜索用时 31 毫秒
31.
V. L. Prisekin N. V. Pustovoi G. I. Rastorguev 《Journal of Applied Mechanics and Technical Physics》2014,55(1):164-171
The efficiency of algorithms for automatic control of forces prescribed in the test program is analyzed by an example of a large-aspect-ratio wing considered as a beam loaded by aerodynamic and inertial forces. 相似文献
32.
Konstantin N. Gavrilov Sergey V. Zheglov Eduard B. Benetsky Anton S. Safronov Eugenie A. Rastorguev Nikolay N. Groshkin Vadim A. Davankov Benjamin Schäffner Armin Börner 《Tetrahedron: Asymmetry》2009,20(21):2490-2496
Two novel P1-stereogenic bisdiamidophosphites derived from (3R,4R)-N-benzyltartarimide as a chiral 1,2-diol have been prepared from readily available starting materials. Palladium and rhodium catalytic systems containing these new P1,P1-bidentate ligands afforded 96%, 83% and 65% ee in asymmetric allylic substitution, hydrogenation and addition processes, respectively. These diastereomeric diamidophosphites were found to be complementary stereoselectors. 相似文献
33.
K. N. Gavrilov S. V. Zheglov P. A. Vologzhanin E. A. Rastorguev A. A. Shiryaev M. G. Maksimova S. E. Lyubimov E. B. Benetsky A. S. Safronov P. V. Petrovskii V. A. Davankov B. Schäffner A. Börner 《Russian Chemical Bulletin》2008,57(11):2311-2319
Synthesis of diastereomeric mono- and bidentate diamidophosphites bearing P*-stereo-centers and phosphabicyclo[3.3.0]octane backbone and their coordination with rhodium(i) and palladium(ii) are considered. Their use in Rh-catalyzed asymmetric allylation allowed one to achieve 87% ee values and the use in Rh-catalyzed asymmetric hydrogenation gave up to 98% ee. 相似文献
34.
S. E. Lyubimov E. A. Rastorguev P. V. Petrovskii T. A. Verbitskaya V. N. Kalinin V. A. Davankov 《Russian Journal of Physical Chemistry B, Focus on Physics》2012,6(8):883-887
New carborane-containing amidophosphites are synthesized. Their effectiveness as ligands in the Rh-catalyzed hydroformylation of alkenes in supercritical carbon dioxide (SC-CO2) is tested. It is shown that the use of carboranylamidophosphites makes it possible to achieve a high degree of conversion at a low catalyst loading. In the SC-CO2 medium, the regioselectivity is higher as compared to the toluene medium. 相似文献
35.
Konstantin N. Gavrilov Sergey V. Zheglov Mariya N. Gavrilova Ivan M. Novikov Marina G. Maksimova Nikolay N. Groshkin Eugenie A. Rastorguev Vadim A. Davankov 《Tetrahedron》2012,68(5):1581-1589
Novel P-monodentate phosphite-type ligands have been synthesized in one step from BINOL mono-tosylate and BINOL mono-(?)-menthylcarbonate. The use of these ligands provides up to 96% ee in Pd-catalyzed asymmetric allylic substitution of (E)-1,3-diphenylallyl acetate and up to 99% ee in Rh-catalyzed asymmetric addition of phenylboronic acid to cyclohex-2-enone. The influence of the structural modules such as the nature of phosphorus-containing ring or exocyclic substituent on the enantioselectivity is discussed. 相似文献
36.
Konstantin N. Gavrilov Alexei A. Shiryaev Sergey V. Zheglov Oksana V. Potapova Ilya V. Chuchelkin Ivan M. Novikov Eugenie A. Rastorguev Vadim A. Davankov 《Tetrahedron: Asymmetry》2013,24(7):409-417
We have designed and synthesized a small library of modular monodentate diamidophosphite ligands with stereogenic phosphorus atoms. The library was prepared efficiently from the commercially available and inexpensive (S)-N-Boc-amino acids. These novel ligands were screened in the Pd-catalyzed asymmetric allylations of (E)-1,3-diphenylallyl acetate with dimethyl malonate as the C-nucleophile with up to 93% ee being obtained. The results showed that the different substituents in the 1,3,2-diazaphospholidine cycle had remarkable effects on the enantioselectivity. 相似文献
37.
G. I. Rastorguev S. I. Snisarenko 《Journal of Applied Mechanics and Technical Physics》2009,50(6):1020-1025
A test facility for transverse shock loading of beams and plates at small impact velocities (up to 40 km/sec) is described. The impact contact force and unsteady strains are determined for a transverse impact on fiber-layered beams
and plates from fiberglass and carbon fiber-reinforced plastic. Pulse shapes are determined for various impact velocities
in the range of 5–40 m/sec. The shock loading and unsteady strain of composite beams and plates are calculated by the finite element method. The finite
elements take into account transverse shears according to the Timoshenko theory and the viscoelastic material behavior according
to the Voigt model. 相似文献
38.
A. M. Badalyan V. I. Belyi N. V. Gel'fond I. K. Igumenov M. L. Kosinova N. B. Morozova A. A. Rastorguev Yu. M. Rumyantsev T. P. Smirnova N. I. Fainer L. V. Yakovkina 《Journal of Structural Chemistry》2002,43(4):556-580
This paper reports results from studies of the chemical composition and structure of semiconducting, dielectric, and metallic films produced from molecular precursors by the chemical vapor deposition method. A study was made of films of zinc sulfides, mixed copper, cadmium, and zinc sulfides, boron nitride, carbonitride, silicon carbonitride, and iridium films. It is shown that the use of metal compounds with different ligands (zinc and manganese) enables production of zinc sulfide films in which manganese ions are uniformly incorporated into the zinc sulfide crystal lattice to substitute zinc at the lattice sites. For the films of simple and mixed cadmium, copper, and zinc sulfides, the film structure depends on the type of substrate. The thin layers of mixed cadmium and zinc sulfides are asubstitution solution with a hexagonal structure. The thin layers of boron nitride produced from borazine exhibit a nanocrystalline structure and are a mixture of cubic and hexagonal phases. Composite layers were produced from alkylamine boranes and their mixtures with ammonia. Depending on synthesis conditions, the layers are mixtures of hexagonal boron nitride, carbide, and carbonitride or pure boron nitride. Using silyl derivatives of asymmetric dimethylhydrazine containing Si—N and C—N bonds in the starting molecule, we produced silicon carbonitride films whose crystal habit belongs to a tetragonal structure with lattice parameters a = 9.6 and c = 6.4 . The iridium films obtained by thermal decomposition of iridium trisacetylacetonate(III) on quartz substrates in the presence of hydrogen have a polycrystalline structure with crystallite sizes of 50 to 500 . A method for determining grainsize composition was proposed, and grain shapes for the iridium films were analyzed. The influence of substrate temperature on the internal microstructure and growth of the iridium films is demonstrated. At the iridium–substrate interface, a transition layer forms, whose composition depends on the substrate material and deposition conditions. 相似文献
39.
A technique is developed for measuring luminescence spectra of hafnium dioxide using a hydrogen lamp as an excitation source.
The luminescence spectra of the as-grown and annealed hafnium dioxide films prepared by chemical deposition from volatile
hafnium dipivaloylmethanate on the Si(111) substrates are measured at room temperature. Intense luminescence at λ ≌ 280 nm
is characteristic of nanocrystallites of monoclinic modification. The band gap width is found to be ≌ 5.76 eV. It is shown
that the film composition significantly deviates from the stoichiometric one.
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Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 63–67, April, 2007. 相似文献
40.
Lyubimov S. E. Rastorguev E. A. Petrovskii P. V. Davankov V. A. 《Russian Chemical Bulletin》2011,60(3):587-589
Rh-Catalyzed asymmetric hydrogenation (up to 85% ee) of (Z)-ethyl 3-acetamido-2-butenoate was carried out for the first time in supercritical CO2 using protic cosolvents. The activity of the Rh catalyst bearing the amidophosphite ligand increases with an increase in
acidity of the protic cosolvents and with hydrogen pressure. 相似文献