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11.
Markov DE Amsterdam E Blom PW Sieval AB Hummelen JC 《The journal of physical chemistry. A》2005,109(24):5266-5274
Exciton diffusion and photoluminescence quenching in conjugated polymer/fullerene heterostructures are studied by time-resolved photoluminescence. It is observed that heterostructures consisting of a spin-coated poly(p-phenylene vinylene) (PPV)-based derivative and evaporated C60 are ill-defined because of diffusion of C60 into the polymer, leading to an overestimation of the exciton diffusion length. This artifact is resolved by the use of a novel, thermally side-chain polymerizing and cross-linking fullerene derivative (F2D) containing two diacetylene moieties, forming a completely immobilized electron acceptor layer. With this heterostructure test system, an exciton diffusion length of 5 +/- 1 nm is derived for this PPV derivative from time-integrated luminescence quenching data. 相似文献
12.
A. N. Tyumentsev A. D. Korotaev Yu. P. Kolobov K. A. Markov Yu. P. Pinzhin S. F. Tyumentseva 《Russian Physics Journal》1982,25(5):447-451
The paper gives the results of investigations on the rate of coalescence of zirconium oxides in Nb-Mo-ZrO2 alloy. On the basis of experimental results and theoretical estimates, it is shown that the stability of zirconium oxides in a niobium matrix increases substantially when the oxygen content in the solid solution rises. A high stability of zirconium oxides in niobium, which ensures a considerable (up to T 1800°C) increase in the recrystallization temperature and enhancement of the mechanical properties of the alloys at T 1100°C can be attained at an oxygen content C0 0.2–0.5 at.% in the solid solution.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 76–79, May, 1982. 相似文献
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S. S. Tulenin S. A. Bakhteev R. A. Yusupov L. N. Maskaeva V. F. Markov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(10):1771-1777
Boundary conditions and ranges of the formation of indium(III) sulfide and selenide upon precipitation by thiocarbamide and selenocarbamide are determined. Potentiometric titration of indium chloride (InCl3) in the concentration range of 0.0001 to 0.100 mol/L by a solution of sodium hydroxide is performed. It is found that the following pH ranges are optimal for In2S3 and In2Se3 film precipitation: from 3.0 to 4.5 and from 9.0 to 14.0. Indium selenide layers 100 to 300 nm thick are prepared on vitroceramic by hydrochemcial precipitation. 相似文献
17.
Dr. Laia Vilà‐Nadal Dr. Scott G. Mitchell Dr. Stanislav Markov Dr. Christoph Busche Dr. Vihar Georgiev Prof. Asen Asenov Prof. Leroy Cronin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(49):16502-16511
We explore the concept that the incorporation of polyoxometalates (POMs) into complementary metal oxide semiconductor (CMOS) technologies could offer a fundamentally better way to design and engineer new types of data storage devices, due to the enhanced electronic complementarity with SiO2, high redox potentials, and multiple redox states accessible to polyoxometalate clusters. To explore this we constructed a custom‐built simulation domain bridge. Connecting DFT, for the quantum mechanical modelling part, and mesoscopic device modelling, confirms the theoretical basis for the proposed advantages of POMs in non‐volatile molecular memories (NVMM) or flash‐RAM. 相似文献
18.
Nataliya A. Samoylova Nikita M. Belov Victor A. Brotsman Dr. Ilya N. Ioffe Dr. Natalia S. Lukonina Dr. Vitaliy Yu. Markov Dr. Adrian Ruff Alexey V. Rybalchenko Paul Schuler Olesya O. Semivrazhskaya Prof. Dr. Bernd Speiser Prof. Dr. Sergey I. Troyanov Prof. Dr. Tatiana V. Magdesieva Dr. Alexey A. Goryunkov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(52):17969-17979
Novel difluoromethylenated [70]fullerene derivatives, C70(CF2)n (n=1–3), were obtained by the reaction of C70 with sodium difluorochloroacetate. Two major products, isomeric C70(CF2) mono‐adducts with [6,6]‐open and [6,6]‐closed configurations, were isolated and their homofullerene and methanofullerene structures were reliably determined by a variety of methods that included X‐ray analysis and high‐level spectroscopic techniques. The [6,6]‐open isomer of C70(CF2) constitutes the first homofullerene example of a non‐hetero [70]fullerene derivative in which functionalisation involves the most reactive bond in the polar region of the cage. Voltammetric estimation of the electron affinity of the C70(CF2) isomers showed that it is substantially higher for the [6,6]‐open isomer (the 70‐electron π‐conjugated system is retained) than the [6,6]‐closed form, the latter being similar to the electron affinity of pristine C70. In situ ESR spectroelectrochemical investigation of the C70(CF2) radical anions and DFT calculations of the hyperfine coupling constants provide evidence for the first example of an inter‐conversion between the [6,6]‐closed and [6,6]‐open forms of a cage‐modified fullerene driven by an electrochemical one‐electron transfer. Thus, [6,6]‐closed C70(CF2) constitutes an interesting example of a redox‐switchable fullerene derivative. 相似文献
19.
A calculation scheme for evaluating the thermal conductivities of polymers from the data on their chemical structures and degrees of crystallinity has been developed. The scheme is a version of the Vargaftik equation for organic liquids that is modified for polymers. In the modified equation, the heat capacity of a polymer, its density, and the reduced molecular mass of the repeating unit are involved. The effect of polar groups responsible for dipole-dipole interactions or the formation of hydrogen bonds and the effect of the van der Waals volume of the repeating unit of a polymer or the repeating fragment of the network are analyzed. It has been taken into account that atoms in the polymer backbone and in side chains contribute differently to thermal conductivity. The effects of temperature and the degree of crystallinity on the studied characteristic are considered. 相似文献
20.
Journal of Mathematical Chemistry - We mathematically analyze the solutions to the dynamical system induced by the two-step exponential (growth-)decay (2SED) reaction network involving three... 相似文献