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131.
T. S. Petkevich Yu. G. Egiazarov N. A. Kovalenko T. L. Sen’ko 《Journal of Applied Spectroscopy》1998,65(1):117-123
Activity of alumocopper-palladium catalysts (0.5 at.% Pd, 0.1–3.0 at.% Cu) which differ in preparation method in CO, C2H4 and CH4 oxidation is studied. It is shown that preliminary modification of a carrier by copper leads to an enhancement of catalyst
activity as compared with an alumopalladium one. With the methods of EDRS, TPR-TRS, and TPR of adsorbed CO and O2, the Pd/Cu/Al2O3, Cu/Pd/Al2O3 and (Pd−Cu)/Al2O3, systems are studied. It is established that premodification of the carrier leads to a weakening of its interaction with
the second metal while the combined deposition from one impregnating solution in subsequent thermal treatment is accompanied
by a strong metal aggregation.
Institute of Physicoorganic Chemistry, National Academy of Sciences of Belarus, 13, Surganov St., Minsk, 220072. Translated
from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 1, pp. 114–120, January–February, 1998. 相似文献
132.
I. Štekl P. Čermák P. Beneš V. B. Brudanin K. N. Gusev V. G. Egorov A. A. Klimenko V. E. Kovalenko A. Kovalík N. I. Rukhadze A. V. Salamatin V. V. Timkin Ts. Vylov Ch. Briançon F. Šimkovic 《Czechoslovak Journal of Physics》2006,56(5):505-510
Present status of the experiment TGV II which is devoted to the measurement of double-beta decay of 106Cd is given. The low background spectrometer TGV II is installed in the Modane Underground Laboratory and has been running
from February 2005 with approx 10 grams of 106Cd enriched at 75%. After an analysis of 3736 hours of experimental data the new improved half-life limit for 2νEC/EC decay of 106Cd (0
g.s.
+
→ 0
g.s.
+
) is given as T
1
2/2ν
> 4.8 × 1019 years (90% CL). The search for 2νEC/EC decay of 106Cd to the excited states of 106Pd allows to determine the limits of the half-lives T
1
2/2ν
(0
g.s.
+
→ 2
1
+
) > 3.9 × 1019 years (90% CL) and T
1
2/2ν
(0
g.s.
+
→ 0
1
+
) > 5.8 × 1019 years (90% CL).
Presented by I. Štekl at the Workshop on calculation of double-beta-decay matrix elements (MEDEX’05), Corfu, Greece, September
26–29, 2005. 相似文献
133.
Laura Kovalenko Martin W. Schr der R. Amaranatha Reddy Siegmar Diele Gerhard Pelzl Wolfgang Weissflog 《Liquid crystals》2005,32(7):857-865
New five-ring bent-core mesogens derived from 4-cyanoresorcinol as the central core have been synthesized. The mesophases were assigned by polarizing microscopy, X-ray diffraction and electro-optical measurements. It was found that the mesophase behaviour clearly depends on the direction of the carboxyl linking groups between the aromatic rings. If the outer and inner ester linking groups of a wing are in the same direction then nematic phases and, for long chain members, SmC and SmCPA phases are observed. If the outer and inner linking groups are in opposing directions a dimorphism, SmA-SmAPA, is observed and the clearing temperatures are increased by about 55 K. It is remarkable that in the SmCPA phases of the first series, polar switching preferably takes place through a collective rotation of the molecules around their long axes which is accompanied by the inversion of the chirality of the smectic layers. 相似文献
134.
Films of polyvinylidene fluoride with tetrafluoroethylene several micron thick were prepared by vacuum electron-beam evaporation
in a static electric field. It is shown that a polymer deposited on a negative electrode possesses a structure similar to
that of uniaxially stretched and polarized films and has a high (up to 85%) content of the piezoactive β phase. The electromechanical coupling coefficient k
33 and the pyrosensitivity of these samples are substantially higher than those of layers deposited under the same conditions
in the absence of a field.
Zh. Tekh. Fiz. 68, 101–103 (December 1998) 相似文献
135.
V. V. Tarasov N. F. Kovalenko Dongxiang Zhang E. G. Sorokin 《Russian Journal of Applied Chemistry》2008,81(12):2122-2126
Coalescence of KHA-30 compressor oil microdroplets on a carbon fabric, aimed to remove them from air and water streams used for compressor cooling, was examined. 相似文献
136.
137.
Conclusions The nitration of polyhaloalkenes was carried out under conditions for the complete conversion of nitric acid to the nitronium cation. Butyl esters of -nitrocarboxylic acids were obtained by esterification of the nitration products.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2814–2815, December, 1985. 相似文献
138.
V. I. Avilkin V. M. Aleksandrov E. V. Kovalenko 《Journal of Applied Mathematics and Mechanics》1985,49(6):770-777
More-accurate equations describing the axisymmetric deformations of elastic, thin-walled elements (coatings) are derived using the asymptotic analysis of the solution to the first fundamental problem of the theory of elasticity for a layer. The notable difference distinguishing these relations from the classical, Kirchhoff-Love and Reissner-Timoshenko equations of flexure of plates, and their modifications /1/, is, that there are no concentrated forces at the edges of the stamp when the corresponding contact problems are solved. Moreover, the formulas obtained contain the equations of classical theory as a special case. The solutions obtained using various applied theories are compared with the corresponding solution obtained using the equations of the theory of elasticity, using the example of the axisymmetric contact problem of impressing a plane circular stamp into a layer lying on a Fuss-Winkler foundation. The characteristic parameters of the problem in question are computed by numerical methods. 相似文献
139.
140.