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511.
White RC Gorelik V Bagryanskaya EG Forbes MD 《Langmuir : the ACS journal of surfaces and colloids》2007,23(8):4183-4191
Time-resolved magnetic resonance experiments (TREPR and CIDNP) are used to investigate previously unobserved redox chemistry of the surfactant dioctyl sulfosuccinate ester (AOT) using the photoexcited triplet state of anthraquinone 2,6-disulfonate (3AQDS*). Several different free radicals resulting from two independent oxidation pathways (electron transfer and hydrogen abstraction) are observed. These include the radical ions of AQDS and sulfite from electron-transfer processes, carbon-centered radicals from H-atom abstraction reactions, and an additional carbon-centered radical formed by electron transfer from the AOT sulfonate head group followed by the loss of SO3. The radicals exhibit intense chemically induced dynamic electron spin polarization (CIDEP) in their TREPR spectra. The intensity ratios of the observed TREPR signals for each radical depend on the water pool size and temperature, which in turn affect the predominant CIDEP mechanism. All signal carriers are accounted for by simulation, and CIDNP results provide strong supporting evidence for the assignments. 相似文献
512.
Harsanyi power solutions for graph-restricted games 总被引:1,自引:0,他引:1
René van den Brink Gerard van der Laan Vitaly Pruzhansky 《International Journal of Game Theory》2011,40(1):87-110
We consider cooperative transferable utility games, or simply TU-games, with limited communication structure in which players can cooperate if and only if they are connected
in the communication graph. Solutions for such graph games can be obtained by applying standard solutions to a modified or restricted game that takes account of the cooperation restrictions.
We discuss Harsanyi solutions which distribute dividends such that the dividend shares of players in a coalition are based on power measures for nodes in corresponding communication graphs. We provide axiomatic characterizations of the Harsanyi power solutions on
the class of cycle-free graph games and on the class of all graph games. Special attention is given to the Harsanyi degree
solution which equals the Shapley value on the class of complete graph games and equals the position value on the class of cycle-free graph games. The Myerson value is the Harsanyi power solution that is based on the equal power measure. Finally, various applications are discussed. 相似文献
513.
Vitaly G. Avakyan Evgeniya P. Doronina Valery F. Sidorkin 《Journal of organometallic chemistry》2011,696(10):1969-1974
Ditopic complex formation of silene H2SiCH2 with bidentate ligands Me2NCH2SiHnF3-n (n = 0-3) was studied at the MP4(SDQ(T)6-311G(d,p))//MP2/6-31G(d,p) levels of theory. The AIM and ELF analyses have shown that π-bonding in the silenic Si1C moiety in the relatively weak (H2Si1CH2)·(Me2NCH2Si2HnF3-n) (n = 2, 3) ditopic complexes is partially preserved. 相似文献
514.
Reichhardt NV Nylander T Klösgen B Alfredsson V Kocherbitov V 《Langmuir : the ACS journal of surfaces and colloids》2011,27(22):13838-13846
Mesoporous silica SBA-15 was modified in a three-step process to obtain a material with poly-N-isopropylacrylamide (PNIPAAM) grafted onto the inner pore surface. Water sorption calorimetry was implemented to characterize the materials obtained after each step regarding the porosity and surface properties. The modification process was carried out by (i) increasing the number of surface silanol groups, (ii) grafting 1-(trichlorosilyl)-2-(m-/p-(chloromethylphenyl) ethane, acting as an anchor for (iii) the polymerization of N-isopropylacrylamide. Water sorption isotherms and the enthalpy of hydration are presented. Pore size distributions were calculated on the basis of the water sorption isotherms by applying the BJH model. Complementary measurements with nitrogen sorption and small-angle X-ray diffraction are presented. The increase in the number of surface silanol groups occurs mainly in the intrawall pores, the anchor is mainly located in the intrawall pores, and the intrawall pore volume is absent after the surface grafting of PNIPAAM. Hence, PNIPAAM seals off the intrawall pores. Water sorption isotherms directly detect the presence of intrawall porosity. Pore size distributions can be calculated from the isotherms. Furthermore, the technique provides information regarding the hydration capability (i.e., wettability of different chemical surfaces) and thermodynamic information. 相似文献
515.
We investigate extraordinary features of optical parametric amplification of Stokes electromagnetic waves that originate from the three-wave mixing of a backward phonon wave with negative group velocity and two ordinary electromagnetic waves. Such properties were earlier shown to exist only in plasmonic negative-index metamaterials that are very challenging to fabricate. Nonlinear optical photonic devices with properties similar to those predicted for negative-index metamaterials are proposed. 相似文献
516.
Wojciech Zielenkiewicz Agniaszka Marcinowicz Sergey Cherenok Vitaly I. Kalchenko 《Supramolecular chemistry》2013,25(3):167-176
The metal cation binding ability of cone-p-tert-butylhexahomotrioxacalix[3]arene tris(acetic acid) was investigated by 1H NMR and complementary semi-empirical calculations. NMR showed significant shifts with Na+, K+, Ag+ and, to a lesser extent, Pb2+. The macrocyclic protons undergoing the greatest shifts imply that these cations bind inside the cavity composed of the phenoxy and carbonyl oxygen atoms. Metal complexes were modelled using a semi-empirical approach and, in general, their geometry optimised structures were in agreement with NMR data. U-tube transport experiments demonstrated that the macrocycle actively transported Cr3+, Fe3+, Co2+ and Cu2+ through the organic phase. 相似文献
517.
Yurii I. Blokhin Flisa M. Galiaskarova Dmttrii V. Gusev Mansur Y. Ergashov Vitaly K. Belsky Edvard E. Nifantyev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract With the aim to create macrocyclic phosphorus-containing heterocycles (new phosphorus crown-ethers) and corresponding polyesters the interaction between dihydric phenols and complete anides of phosphoric and phenylphosphonic acids was studied. It was shown that, according to reaction conditions and reagents ratio, the resulting products can have a linear structure, with oligo- (A) or polymexic (B) molecules, and a macrocyclic structure (C) alike : phospho(III)arylene crown-ethers obtained for example by the consecutive assembling of planned macrocyclic systems or by the direct interaction. 相似文献
518.
We find some sufficient conditions for a system of partial derivatives of an entire function to be complete in the space H(Cd) of all entire functions of d variables. As an application of this result we describe new classes of frequently hypercyclic operators on H(Cd). 相似文献
519.
Dariusz R. Kowalski Eyal Nussbaum Michael Segal Vitaly Milyeykovsky 《Optimization Letters》2014,8(2):777-799
In this paper we consider online scheduling problems for linear topology under various objective functions: minimizing the maximum completion time, minimizing the largest delay, and minimizing the sum of completion times. We give optimal solutions for uni-directional version of the problem for each of the objectives and show that for the two-directional versions of each problem, no online algorithm can deterministically achieve the optimal solution for any of the considered objective functions. We also propose 2-approximation on-line algorithms for the MinMakespan and the MinSum minimization objectives. We also prove that no online algorithm can deterministically achieve the optimal solution for any of the considered objective functions for the weighted case of uni-directional scenarios. 相似文献
520.
Four new low-band-gap alternating copolymers (P-1, P-2, P-3 and P-4) based on electron-rich benzodithiophene and newly developed electron-deficient units, thienopyrazine or dithiadiazatrindene derivatives, were synthesized by Stille polycondensation. All polymers exhibit good solubility in common organic solvents and a broad absorption band in the visible to near-infrared regions. The film optical band gaps of the polymers are in the range of 1.28-2.07 eV and the highest occupied molecular orbital (HOMO) energy levels are in the range of-4.99 eV to -5.28 eV. Bulk heterojunction polymer solar cells (PSCs) of the polymers were fabricated with phenyl-C61-butyric acid methyl ester (PC61BM) as acceptor material, and a power conversion efficiency of 0.80% was realized with P-1 as donor material. 相似文献