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排序方式: 共有599条查询结果,搜索用时 31 毫秒
1.
Dr. Yulia Y. Enakieva Dr. Anna A. Sinelshchikova Prof. Mikhail S. Grigoriev Prof. Vladimir V. Chernyshev Dr. Konstantin A. Kovalenko Prof. Irina A. Stenina Prof. Andrey B. Yaroslavtsev Prof. Yulia G. Gorbunova Prof. Aslan Y. Tsivadze 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(45):10552-10556
The design of new solid-state proton-conducting materials is a great challenge for chemistry and materials science. Herein, a new anionic porphyrinylphosphonate-based MOF ( IPCE-1Ni ), which involves dimethylammonium (DMA) cations for charge compensation, is reported. As a result of its unique structure, IPCE-1Ni exhibits one of the highest value of the proton conductivity among reported proton-conducting MOF materials based on porphyrins (1.55×10−3 S cm−1 at 75 °C and 80 % relative humidity). 相似文献
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Statistical Inference with Fractional Brownian Motion 总被引:3,自引:1,他引:2
Kukush Alexander Mishura Yulia Valkeila Esko 《Statistical Inference for Stochastic Processes》2005,8(1):71-93
We give a test between two complex hypothesis; namely we test whether a fractional Brownian motion (fBm) has a linear trend against a certain non-linear trend. We study some related questions, like goodness-of-fit test and volatility estimation in these models. 相似文献
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A. S. Romakhin I. M. Zaripov Yu. G. Budnikova Yu. M. Kargin E. V. Nikitin A. P. Tomilov Yu. A. Ignat'ev 《Russian Chemical Bulletin》1992,41(6):1036-1040
The mechanism of the electrosynthesis of phosphate esters from white phosphorus was investigated. It was shown that the reaction takes place by two paths, i.e., monomeric (with the participation of dissolved phosphorus) and polymeric (with the participation of phosphorus on the surface of an emulsion drop). It was established that in an alcohol solution of tetraethylammonium iodide the main part of the final product is formed through an intermediate polymeric compound. It was noticed that by studying the dynamics of the accumulation of the dissolved product during electrolysis it is possible to trace the mechanism of reaction of the phosphorus at the individual stages of the process.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420028 Kazan'. V. I. Ul'yanov-Lenin Kazan' State University, 420028 Kazan'. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 6, pp. 1328–1333, June, 1992. 相似文献
6.
Fabien Fontaine Evan Bolton Yulia Borodina Stephen H Bryant 《Chemistry Central journal》2007,1(1):12-14
Background
Large chemical databases require fast, efficient, and simple ways of looking for similar structures. Although such tasks are now fairly well resolved for graph-based similarity queries, they remain an issue for 3D approaches, particularly for those based on 3D shape overlays. Inspired by a recent technique developed to compare molecular shapes, we designed a hybrid methodology, alignment-recycling, that enables efficient retrieval and alignment of structures with similar 3D shapes. 相似文献7.
D. G. Yakhvarov Yu. G. Budnikova O. G. Sinyashin 《Russian Journal of Electrochemistry》2003,39(11):1261-1270
Electrochemical reduction of nickel complexes with 2,2-bipyridyl in the presence of ortho-substituted aromatic bromides or white phosphorus leads to the formation of highly reactive organonickel -complexes that are capable of selectively reacting with diverse substrates with the formation of cross-association products. Mechanisms of electrocatalytic processes involving organic halides, chlorophosphines, white phosphorus, and nickel complexes with 2,2-bipyridyl are studied by the cyclic voltammetry and preparative electrolysis methods. Key intermediates of processes that occur in metallocomplex catalysis are determined. 相似文献
8.
Yakhvarov D. G. Budnikova Yu. H. Tazeev D. I. Sinyashin O. G. 《Russian Chemical Bulletin》2002,51(11):2059-2064
The material of the sacrificial anode has a substantial effect on the nature and yield of the target products of electrochemical phosphorylation of organic halides by white phosphorus in the presence of the nickel complexes with 2,2"-bipyridine. The use of the zinc anode results in the products with tricoordinated phosphorus, viz., triorganylphosphines, the reaction on the aluminum anode affords triorganylphosphine oxides, and the presence of Mg2+ ions in the reaction mixture provides the transformation of white phosphorus into cyclic phosphines (PhP)5. 相似文献
9.
Budnikova Yu. H. Kafiyatullina A. G. Sinyashin O. G. Abdreimova R. R. 《Russian Chemical Bulletin》2003,52(4):929-938
In the presence of white phosphorus the redox potentials of the copper ions change and the potential of the reduction wave of CuI/Cu0 shifts noticeably toward more positive values. The CuI—P4 complex is characterized by a lower value of the electrochemical gap, that is, higher polarizability and reactivity compared to those of the free CuI cation. Phosphorus esters can be synthesized from P4 and ethanol. The latter is in the composition of the copper(ii) complexes, which act as a catalyst-charge mediator. 相似文献
10.
B. A. Trofimov N. K. Gusarova S. F. Malysheva V. A. Kuimov B. G. Sukhov S. I. Shaikhudinova N. P. Tarasova Yu. V. Smetannikov O. G. Sinyashin Yu. G. Budnikova T. I. Kazantseva V. I. Smirnov 《Russian Journal of General Chemistry》2005,75(9):1367-1372
The example of the phosphorylation of styrene and 2-vinylnaphthalene with elemental phosphorus in the KOH-DMSO system at room or elevated temperature was used to show that the activated red phosphorus prepared from white phosphorus under ionizing radiation has a reactivity comparable with that of white phosphorus and significantly higher than that of ordinary technical red phosphorus. 相似文献