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31.
32.
Electrochemical behavior of cadmium and tellurium ions in their joint reduction on a glassy carbon electrode in a nonaqueous
electrolyte based on ethylene glycol was studied. An X-ray phase analysis and transmission electron microscopy were used to
determine the phase composition and particle size of the electrodeposited CdTe films. 相似文献
33.
Continuing our ongoing studies on cytotoxic substances, we report the synthesis and cytotoxic properties of a series of symmetric 1,5‐diamino‐9,10‐anthraquinones with potentially bioreducible groups. Symmetric amination of 1,5‐dichloro‐9,10‐anthraquinone with the appropriate primary amines in the presence of DMF furnished the structurally related aminoanthraquinone analogs 1 – 19 . Their in vitro cytotoxic activity was evaluated using rat glioma C6 cells, human hepatoma G2 cells, and 2.2.15 cells. Several compounds exhibited very high antitumor activities in these assays. Compound 4 efficiently inhibited C6 cells, human hepatoma G2 cells, and 2.2.15 cells, as determined by means of the XTT colorimetric assay. The antiproliferative activity of 4 was markedly enhanced, reaching a potency comparable to those of the powerful anticancer agents mitoxantrone, adriamycin, and cisplatin. Biological evaluations and structure/activity relationships within this class of novel aminoanthraquinones are discussed. 相似文献
34.
The interaction of technetium with 1,3,5-triphenyl-Δ2-pyrazoline (TPP) is examined and kinetic methods for the determination of technetium (0.01–1.2 mg l?1) are developed; absorbances are measured at 678 nm. The optimal hydrochloric acid concentration for the reaction is 8.3 M, with a TPP concentration of 6.6 × 10?5 M in 15 % (v/v) ethanol. Interferences by Cu(II), V(V) and Fe(III) are discussed. The method is applied to two synthetic nuclear fuels and to vegetation spiked with technetium. 相似文献
35.
本文介绍了基于过零检测谱分析仪的基本原理,讨论了它的工程实现及有关技术指标。这种谱仪回避了A/D转换器的限制,是信号谱估计的一种新理论和新技术。 相似文献
36.
Henrik-Alexander Christ Pen Yiao Ang Fuzhao Li Hans-Hermann Johannes Wolfgang Kowalsky Henning Menzel 《Journal of polymer science. Part A, Polymer chemistry》2022,60(4):715-725
The fabrication of micron-sized poly(methyl methacrylate) (PMMA) polymer optical fibers doped with rhodamine B as an organic dye is demonstrated. Highly aligned and defect-free fibers are fabricated by using the stable jet electrospinning (SJES) method and systematically varying critical parameters such as solvent type and polymer concentration. At optimal conditions, for example, a polymer concentration of 35 wt% of PMMA in butanone, ribbon-shaped fibers with a smooth surface and diameter of about 20 μm could be spun using SJES mode and deposited on a rotating drum as target in a highly aligned manner. Photoluminescence spectra of the doped fibers excited longitudinally and transversely with a laser show an excitation peak with full-width-at-half-maximum of only 5.05 nm and a low lasing threshold at a pump energy of 0.55 μJ, indicating that SJES could become a new source of amplified optics components or organic solid-state fiber lasers. 相似文献
37.
N.N. Vyukhina I.S. Gibin V.A. Dombrovsky S.A. Dombrovsky B.N. Pankov E.F. Pen A.N. Potapov A.M. Sinyukov P.E. Tverdokhleb V.V. Shelkovnikov 《Optics & Laser Technology》1996,28(4):269-276
Results of studying a holographic memory to write/read digital data pages are presented. The research has been carried out in Novosibirsk, Russia. Great attention was paid to methods of improving recording density and the reliability of data reading, the development of ‘dry’ photopolymers that provide recording of superimposed three-dimensional phase holograms, and the designing of parallel optic input large-scale integration (LSI) for reading and logical processing of data arriving from the holographic memory. 相似文献
38.
A form of three-boson Skornyakov-Ter-Martirosyan equations differential in the momentum space is proposed. This form makes it possible to directly use the Danilov condition for self-adjointness of the three-particle Hamiltonian with zero-range pair interactions. The numerical solution for the system of differential equations of the Heun class is compared with the solutions for the Faddeev equations for the problem of determining the helium trimer spectrum. 相似文献
39.
Yu. P. Kuznetsov A. K. Khripunov E. V. Kruchinina V. M. Kuznetsov L. D. Turkova A. V. Pen’kova 《Russian Journal of Applied Chemistry》2004,77(11):1877-1882
Mass-exchange characteristics of cellulose myristate or acetomyristate membranes in separating aqueous-organic, organic, or gas mixtures, particularly, in recovering aromatic hydrocarbons from binary mixtures with aliphatic alcohols, and also ethyl acetate from a mixture of esterification products, are studied.Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 11, 2004, pp. 1895–1900.Original Russian Text Copyright © 2004 by Yu. Kuznetsov, Khripunov, Kruchinina, V. Kuznetsov, Turkova, Penkova. 相似文献
40.
V. V. Shelkovnikov E. F. Pen V. I. Kovalevskii E. V. Vasil’ev V. V. Russkikh T. N. Gerasimova 《Optics and Spectroscopy》2004,97(6):970-977
The possibility of recording holograms in thick layers of a photopolymeric material on the basis of a forbidden singlet-triplet transition of a sensitizing dye, erythrosine, is theoretically substantiated and experimentally confirmed. A single hologram and 16 superimposed holograms are recorded with a low-power He-Ne laser (632 nm) at high concentrations of the sensitizing dye and high optical densities in the range of its main absorption. The diffraction efficiency of the single hologram is ~50%. The dependence of the increase in the diffraction efficiency of a transmission grating in samples of photopolymeric material on the intensity of incident radiation of a Kr+ laser (647 nm) is studied. The observed linear dependence of the maximal rate of increase in the diffraction efficiency in the photopolymer on the incident light intensity is explained by the manifestation of a two-step excitation of the dye (T 1←S 0, T 2←T 1) in the samples studied. 相似文献