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61.
Dmitrii Zinoviev 《Israel Journal of Mathematics》1998,106(1):29-77
We relate the “Fourier” orbital integrals of corresponding spherical functions on thep-adic groups SO(5) and PGL(2). The correspondence is defined by a “lifting” of representations of these groups. This is a
local “fundamental lemma” needed to compare the geometric sides of the global Fourier summation formulae (or relative trace
formulae) on these two groups. This comparison leads to conclusions about a well known lifting of representations from PGL(2)
to PGSp(4). This lifting produces counter examples to the Ramanujan conjecture. 相似文献
62.
Adrian Badura Dmitrii Guschin Berndt Esper Tim Kothe Sebastian Neugebauer Wolfgang Schuhmann Matthias Rögner 《Electroanalysis》2008,20(10):1043-1047
Photosystem 2 (PS2) that catalyses light driven water splitting in photosynthesis was ‘wired’ to electrode surfaces via osmium‐containing redox polymers based on poly(vinyl)imidazol. The redox polymer hydrogel worked as both immobilization matrix and electron acceptor for the enzyme. Upon illumination, the enzymatic reaction could be switched on and a catalytic current was observed at the electrode. The catalytic current is directly dependent on the intensity of light used for the excitation of PS2. A typical current density of 45 μA cm?2 at a light intensity of 2.65 mW cm?2 could be demonstrated with a significantly improved operational stability. 相似文献
63.
64.
Aldous DJ Batsanov AS Yufit DS Dalençon AJ Dutton WM Steel PG 《Organic & biomolecular chemistry》2006,4(15):2912-2927
Flash vacuum pyrrolysis of vinyl epoxides provides cis-dihydrofuran carboxylic esters in good yields and diastereoselectivities, which, on base-promoted epimerisation afford the complementary trans series. The compounds provide a viable template for a Lewis acid promoted cyclisation to provide the 2,6-diaryl-3,7-dioxabicyclo[3.3.0]octane core found in the furofuran series of natural lignans. This strategy is stereodivergent and can be controlled to provide the exo-exo, exo-endo or endo-endo stereochemistries. The approach has been exemplified in syntheses of the sesamyl furofurans (+/-)-epiasarinin and (+/-)-asarinin. 相似文献
65.
66.
Dmitrii O. Kharchenko Olga M. Shchokotova Irina O. Lysenko Vasyl O. Kharchenko 《辐射效应与固体损伤》2013,168(7-8):584-600
We study a change in mechanical properties of binary systems subjected to irradiation influence described by ballistic flux of atomic mixing having regular and stochastic contributions. By using numerical modeling based on the phase field approach we study dynamics of deformation fields in a previously irradiated system and in the binary system deformed during irradiation. An influence of both deterministic and stochastic components of ballistic flux onto both yield strength and ultimate strength is studied. We have found that degradation of mechanical properties relates to the formation of percolating clusters of shear bands. Considering a hardening coefficient we analyze stages of plastic deformation of both initially irradiated alloy and alloy subjected to sustained irradiation. Stability of binary alloy under mechanical loading in the form of shear strain with a constant rate and cyclic deformation is discussed. 相似文献
67.
Alexander V. Aksenov Igor Yu. Grishin Nicolai A. Aksenov Vladimir V. Malyuga Dmitrii A. Aksenov Mezvah A. Nobi Michael Rubin 《Molecules (Basel, Switzerland)》2021,26(14)
Nitroalkanes activated with polyphosphoric acid serve as efficient electrophiles in reactions with various nucleophilic amines. Strategically placed second functionality allows for the design of annulation reactions enabling preparation of various heterocycles. This strategy was employed to develop an innovative synthetic approach towards 3,4-dihydroquinazolines from readily available 2-(aminomethyl)anilines. 相似文献
68.
Aleksey Tyazhev Georgi Marchev Valeriy Badikov Adolfo Esteban‐Martin Dmitrii Badikov Vladimir Panyutin Galina Shevyrdyaeva Svetlana Sheina Anna Fintisova Valentin Petrov 《Laser \u0026amp; Photonics Reviews》2013,7(4):L21-L24
The defect chalcopyrite crystal HgGa2S4 has been employed in a 1064‐nm pumped optical parametric oscillator operating at 100 Hz, to generate ∼5 ns long idler pulses near 4 µm with energies as high as 6.1 mJ and average power of 610 mW. At crystal dimensions comparable to those available for the commercial AgGaS2 crystal, operation of the 1064‐nm pumped HgGa2S4 OPO is characterized by much lower pump threshold and higher conversion efficiency, with the most important consequence that such a device might become practical at pump levels sufficiently lower than the optical damage threshold. 相似文献
69.
Thaksen Jadhav Yuan Fang William Patterson Cheng‐Hao Liu Ehsan Hamzehpoor Dmitrii F. Perepichka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(39):13891-13895
Designing structural order in electronically active organic solids remains a great challenge in the field of materials chemistry. Now, 2D poly(arylene vinylene)s prepared as highly crystalline covalent organic frameworks (COFs) by base‐catalyzed aldol condensation of trimethyltriazine with aromatic dialdehydes are reported. The synthesized polymers are highly emissive (quantum yield of up to 50 %), as commonly observed in their 1D analogues poly(phenylene vinylene)s. The inherent well‐defined porosity (surface area ca. 1000 m2 g?1, pore diameter ca. 11 Å for the terephthaldehyde derived COF‐1) and 2D structure of these COFs also present a new set of properties and are likely responsible for the emission color, which is sensitive to the environment. COF‐1 is highly hydrophilic and reveals a dramatic macroscopic structural reorganization that has not been previously observed in framework materials. 相似文献
70.