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41.
Kutsenko AA Shuvalov AL Norris AN 《The Journal of the Acoustical Society of America》2011,130(6):3553-3557
A scheme for evaluating the effective quasistatic speed of sound c in two- and three-dimensional periodic materials is reported. The approach uses a monodromy-matrix operator to enable direct integration in one of the coordinates and exponentially fast convergence in others. As a result, the solution for c has a more closed form than previous formulas. It significantly improves the efficiency and accuracy of evaluating c for high-contrast composites as demonstrated by a two-dimensional scalar-wave example with extreme behavior. 相似文献
42.
Leonid G. Voskressensky Larisa N. KulikovaSergey V. Gozun Victor N. KhrustalevTatiana N. Borisova Anna V. ListratovaMaxim V. Ovcharov Alexey V. Varlamov 《Tetrahedron letters》2011,52(32):4189-4191
The first synthesis of tetrahydrochromeno[4,3-d]azocines via an alkyne-induced expansion reaction is described. 相似文献
43.
All-Union Scientific Research Institute of Nondestructive Testing, Kishinev. Odessa Polytechnical Institute. Translated from Prikladnaya Mekhanika, Vol. 26, No. 1, pp. 77–82, January, 1990. 相似文献
44.
Institute of High-Molecular Compounds, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 4, pp. 36–45, July–August, 1991. 相似文献
45.
Rodica Olar Mihaela Badea Dana Marinescu Larisa Calu Cristina Bucur 《Journal of Thermal Analysis and Calorimetry》2011,105(2):571-575
Novel complexes of type [M2LCl4]·nH2O ((1) M:Ni, n = 5; (2) M:Cu, n = 0 and (3) M:Zn, n = 2; L: ligand resulted from 1,2-phenylenediamine, 3,6-diazaoctane-1,8-diamine and formaldehyde template condensation) were
synthesised and characterised. The features of complexes have been assigned from microanalytical, IR and UV–Vis data. The
thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them.
Processes as water or hydrochloric acid elimination as well as oxidative degradation of the organic ligand were observed.
Complexes display a different thermal behaviour as result of dissimilar chemical interaction of metal ions with chloride anions.
The final product of decomposition was metal(II) oxide as powder X-ray diffraction indicated. 相似文献
46.
We study a differential game of approach in a system whose dynamics is described by a Sobolev‐type second‐order operator differential equation in Hilbert spaces. Solutions of the equation are represented by cosine and sine operator functions. To obtain solvability conditions of the game problem, we use support functionals of two sets, which defined by the behaviors of pursuer and evader. The results are applied to the investigation of conflicted‐controlled dynamics of bending waves in a rod. 相似文献
47.
Larisa Popova Olga Ivanchenko Evgeniia Pochkaeva Sergey Klotchenko Marina Plotnikova Angelica Tsyrulnikova Ekaterina Aronova 《Molecules (Basel, Switzerland)》2021,26(13)
The increased complexity due to the emergence and rapid spread of new viral infections prompts researchers to search for potential antiviral and protective agents for mucous membranes among various natural objects, for example, plant raw materials, their individual components, as well as the products of their chemical modification. Due to their structure, resin acids are valuable raw materials of natural origin to synthesize various bioactive substances. Therefore, the purpose of this study was to confirm the possibility of using resin acid derivatives for the drug design. As a result, we studied the cytotoxicity and biological activity of resin acid derivatives. It was shown that a slight decrease in the viral load in the supernatants was observed upon stimulation of cells (II) compared with the control. When using PASS-online modeling (Prediction of Activity Spectra for Substances), the prediction of the biological activity spectrum showed that compound (I) is capable of exhibiting antiviral activity against the influenza virus. The use of the SWISS-ADME webserver to reveal the drug-like properties of compounds did not directly indicate the presence of antiviral activity. These results indicate the potential of resin acid derivatives as a starting point for extensive research in the study of biological activity. 相似文献
48.
Nikolai A. Ustynyuk Oleg V. Gusev Lyudmila N. Novikova Mikhail G. Peterleitner Larisa I. Denisovich Tat’yana A. Peganova Oleg V. Semeikin Dmitry A. Valyaev 《Journal of Solid State Electrochemistry》2007,11(12):1621-1634
In this review, redox-induced reactions of π- and σ,π-complexes leading to the selective formation (or cleavage) of C–H, C–C,
and C–O bonds have been summarized. To illustrate the synthetic potential of such methodology, the following representative
reactions studied in our group are discussed: (1) oxidatively induced hydrogen elimination from “open” cyclic diene and dienyl
complexes resulting in formation of “closed” dienyl and arene complexes, respectively; (2) reductive activation of C–H bonds
in diene, vinylidene, and carbyne complexes forming new multiple C–C bonds; (3) oxidative dehydrodimerization of vinylidene
complexes into binuclear μ-divinylidene species; and (4) oxidatively induced addition of oxygen nucleophiles to μ-divinylidene
complexes affording cyclic μ-dicarbene derivatives.
Oleg V. Gusev, deceased on October 31. 相似文献
49.
Yan Z. Voloshin Oleg A. Varzatskii Larisa G. Tomilova Marya O. Breusova Tatiana V. Magdesieva Yurii N. Bubnov Roland Krämer 《Polyhedron》2007
Ditopic oximehydrazonate iron(II) phthalocyaninoclathrochelates were synthesized by a transmetallation (a capping group exchange) reaction of the initial labile triethylantimony-capped clathrochelate iron(II) oximehydrazonates with lutetium(III) phthalocyanine as a Lewis acid. The complexes obtained were characterized using elemental analysis, PD and MALDI-TOF mass spectrometries, IR, UV–Vis, 57Fe Mössbauer, and 1H, 13C{1H} NMR spectroscopies. An encapsulated iron(II) ion was found to be in a low-spin state. The cyclic voltammograms show oxidation and reduction waves assignable to Fe2+/3+ couples of macrobicyclic framework and to phthalocyanine macrocycles. 相似文献
50.
Linear tetrahedral finite elements whose dihedral angles are all nonobtuse guarantee the validity of the discrete maximum
principle for a wide class of second order elliptic and parabolic problems. In this paper we present an algorithm which generates
nonobtuse face-to-face tetrahedral partitions that refine locally towards a given Fichera-like corner of a particular polyhedral
domain.
The first author was supported by the Swedish Foundation for Strategic Research, the second author was supported by Grant
No. 49051 of the Academy of Finland, the third author was supported by Grant No. A 1019201 of the Academy of Sciences of the
Czech Republic and by Institutional Research Plan AV0Z 10190503. 相似文献