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1.
This paper is concerned with information revelation in single-item auctions. We compute how much data needs to be transmitted in three strategically equivalent auctions—the Vickrey auction, the English auction and the recently proposed bisection auction—and show that in the truth-telling equilibrium the bisection auction is the best performer.  相似文献   
2.
Kinetics of p-cumylphenol alkylation by isobutylene in the presence of 0.1–2 wt.% p-toluenesulfonic acid has been studied and a reaction scheme is suggested. The rate constants have been determined.
- 0,1–2 % . -. .
  相似文献   
3.
High (Z)-stereoselectivity of olefination of methyl α-phenylthioalkyl and methyl α-phenylthioalkenyl ketones with methyl trimethylsilylacetate decreases in the case of ketones containing a higher alkyl-substituent in place of the methyl group. Dedicated to Corresponding Member of the Russian Academy of Sciences E. P. Serebryakov on the occasion of his 70th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 1020–1021, April, 2005.  相似文献   
4.
New germanium-containing tungsten carbyne complexes Ph3GeC≡W(CH2R)3 (R = But or SiMe3) were synthesized by the reaction of the alkoxy derivative Ph3GeC≡W(OBut)3 with alkyllithium reagents RCH2Li. The new compounds were isolated in individual form as crystals in 95 and 90% yields, respectively, and were characterized by elemental analysis, 1H and 13C NMR spectroscopy, and X-ray diffraction. X-ray diffraction study showed that the coordination environment of the W and Ge atoms in the Ph3GeC≡ W(CH2But)3 and Ph3GeC≡W(CH2SiMe3)3 complexes can be described as a distorted tetrahedron. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 213—216, February, 2006.  相似文献   
5.
The mineral and microelement composition of natural manganese minerals from iron-manganese concretions of the Bol’shoe Miassovo lake (South Ural) is investigated. The structural transformations of the samples under the effect of different temperatures are studied. Apart from layered 9.6 Å and 7.2 Å structures of manganese minerals the lake samples often contain various manganese-containing carbonates. For carbonate minerals by IR spectroscopy the dependence of the wavenumbers of ν2 and ν4 vibrations of the CO3 group on the mineral composition is analyzed. The composition of macro- and microelements of iron-manganese concretions of Bol’shoe Miassovo lake varies in wide ranges not only in different samples, but also in different parts of the same sample. An analysis of the microstructure of lake manganese concretions revealed their biomorphic nature that is exhibited in globe-shaped to filament organic bacterial forms.  相似文献   
6.
Journal of Structural Chemistry - Scanning electron microscopy, X-ray diffraction, Raman and Mössbauer spectroscopies, field and temperature dependences of magnetic saturation and...  相似文献   
7.
Results on conjugate convective heat transfer in a system geometrically similar to the system “crystal-gas-growing vessel shell” of a growing vessel obtained by the Czochralski method are presented. Equations of thermal gravitation convection in Boussinesq approximation are solved by the finite element method in the following variables: temperature, stream function, and vorticity in cylindrical coordinates. Heat transfer from the crystal was studied within the range of Grashof number 100 ≤ Gr ≤ 104 for the fixed configuration of calculation domain. Dependence of the temperature field in the silicon crystal on convection intensity in gas (argon) was examined.  相似文献   
8.
Kim  S. V.  Baikenov  M. I.  Ainabaev  A. A.  Ibishev  K. S.  Meiramov  M. G.  Grigorieva  V. P.  Ma  F. 《High Energy Chemistry》2022,56(3):201-207
High Energy Chemistry - Optimal conditions for producing ultrafine iron powder by combining the processes of electrolysis and high-voltage discharge have been determined. It has been established...  相似文献   
9.
Warren"s method, which has been proposed for the synthesis of -phenylthiodialkyl ketones, appeared to be inefficient for the preparation of their alkenyl alkyl analogs. The latter were prepared in good yields by alkenylation of alkyl phenylthiomethyl ketones with alkenyl bromides.  相似文献   
10.
Autooscillation of the surface tension is a phenomenon related to Marangoni instability periodically arising and fading by dissolution of a surfactant droplet under a water-air interface. A detailed experimental investigation was performed to clear up the influence of the system geometry on development and characteristics of autooscillations. It was found that the aspect ratio is an additional dimensionless parameter that determines the system behavior equally to the Marangoni number. The influence of the cell diameter, capillary immersion depth, and droplet radius on the autooscillation period and amplitude was studied as well.  相似文献   
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