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51.
Marin Marin 《Nonlinear Analysis: Real World Applications》2009,10(3):1572-1578
In the present paper we generalize the results obtained by Iesan and Quintanilla for microstretch elastic bodies in order to cover dipolar elastic materials with stretch. For the boundary value problem considered in this context, we prove a generalized existence result and, also, an extension of the principle of minimum potential energy. 相似文献
52.
V. S. Litvin A. D. Belyaev S. M. Ignatov V. G. Nedorezov R. A. Sadykov A. A. Alekseev E. V. Kuznetsova V. L. Kuznetsov V. N. Marin V. I. Ivanov 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(2):219-221
ZnS(Ag)/6LiF and LiI(Eu) scintillators for thermal neutron detectors have been investigated and neutron detectors based on these scintillators and photomultipliers have been tested. The efficiencies of these detectors are 5 and 66%, respectively. The possibility of developing position-sensitive detectors of thermal neutrons with high space and time resolution is discussed. 相似文献
53.
Lidia Matesic Julie M. Locke Kara L. Vine Marie Ranson John B. Bremner Danielle Skropeta 《Tetrahedron》2012,68(34):6810-6819
To further expand the structure–cytotoxic activity relationships of isatin derivatives and to reduce flexibility in substituent groups at nitrogen, 20 analogues incorporating a ring system between the N1 and C7 atoms of isatin were prepared using a variety of synthetic strategies. This yielded pyrroloindole-, pyrroloquinoline-, pyrroloacridine-, pyrrolophenanthridine- and benzopyrrolophenanthridine-based systems with embedded isatin moieties, the latter possessing a novel carbon skeleton. These compounds were subsequently assessed for their in vitro cytotoxicity against human U937 lymphoma cells, with the brominated pyrroloacridine dione 27 showing the most promising activity (IC50 3.01 μM) after 24 h. 相似文献
54.
Lidia Jasinska Cor E. Koning 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5907-5915
A new experimental approach for preparing biobased, water‐soluble polyesters (PEs) via titanium(IV) n‐butoxide‐catalyzed bulk polycondensation is presented. In the described method polymers were obtained from isosorbide, maleic anhydride and poly(ethylene glycol) (PEG). The chemical structure of the synthesized PEs was confirmed using 2D NMR spectroscopy and by titration methods. Careful analysis of 2D NMR spectra viz. correlation spectra (COSY), heteronuclear single quantum correlation spectra (HSQC) and heteronuclear multiple‐bond correlation spectra (HMBC) allowed to accomplish the complete proton assignment of isosorbide, PEG, and unsaturated acid residues in the PEs. Moreover, by using NMR spectroscopy the transformation of maleic anhydride into fumaric acid ester and the absence of maleic acid ester units in the final polymer were proven. However, during polycondensation part of the unsaturated bonds has reacted in a Michael addition with isosorbide or PEG. Gel permeation chromatography measurements revealed that the unsaturated PEs have Mn values in the range 3000–5000 g/mol. These PEs, with a low content of carboxylic acid end groups, exhibited sufficient thermal resistance for practical applications, for example, as free radical curable coatings. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
55.
N. I. Alekseev S. N. Bol’shagin E. A. Gomin S. S. Gorodkov M. I. Gurevich M. A. Kalugin A. S. Kulakov S. V. Marin A. P. Novosel’tsev D. S. Oleynik A. V. Pryanichnikov E. A. Sukhino-Khomenko D. A. Shkarovskiy M. S. Yudkevich 《Physics of Atomic Nuclei》2012,75(14):1634-1646
The software developed within the framework of the MCU project which implements the Monte Carlo method for solving the transport equations for various kinds of radiation is widely used for calculating nuclear reactors of different types. The final version of MCU-5 is described. The developed libraries of constants are briefly described, and the potentialities of the MCU-5 package modules and the executable codes compiled from them are characterized. Examples of important problems of reactor physics solved with the codes from the MCU family are presented. 相似文献
56.
Lidia Angeleri-Hü gel Jan Trlifaj 《Transactions of the American Mathematical Society》2002,354(11):4345-4358
Let be a right noetherian ring and let be the class of all finitely presented modules of finite projective dimension. We prove that findim iff there is an (infinitely generated) tilting module such that pd and . If is an artin algebra, then can be taken to be finitely generated iff is contravariantly finite. We also obtain a sufficient condition for validity of the First Finitistic Dimension Conjecture that extends the well-known result of Huisgen-Zimmermann and Smalø.
57.
We study, theoretically and experimentally, the evolution of patterns in a passive nonlinear cavity that is longer than the coherence length of the light circulating in it. The patterns exhibit spatial line narrowing as the feedback is increased, resembling the line narrowing in lasers. 相似文献
58.
Ph. Gavillet C. Dionisi A. Gurtu R.J. Hemingway M.J. Losty J.C. Marin M. Mazzucato L. Montanet E. Pagiola R. Blokzijl B. Jongejans J.C. Kluyver G.G.G. Massaro J.J. Engelen J.S.M. Vergeest M. Zralek B. Foster P. Grossmann J. Wells 《Physics letters. [Part B]》1978,78(1):158-161
The backward production of the B(1235) meson is studied in the reaction K?p→Σ?π+ω. This reaction is observed in the final state Σ?π+π+π?π0. A π+ω mass enhancement is visible in the region of the B meson for events with small |u|K? →Σ?) squared four-momentum transfer. The properties of the enhancement agree with those of the B meson. The cross section for K?p→Σ?B+ at incident K? momentum is (3.2 ± 0.5) μb. The backward production of the B meson is compared with similar baryon exchange productions of the A1 and C(Q1) axial vector mesons observed in the same experiment. 相似文献
59.
60.
R.J. Hemingway R. Armenteros C. Dionisi Ph. Gavillet A. Gurtu S.O. Holmgren M.J. Losty J.C. Marin M. Mazzucato L. Montanet M. Banting R. Blokzijl A.J. De Groot B. Jongejans J.C. Kluyver W.M. Van Leeuwen G.G.G. Massaro J. Wells 《Nuclear Physics B》1978,142(3):205-219
Forty events have been observed in a large (133 events/βb) experiment at 4.2 GeV/c incident K? momentum. Thirty nine of the events come from the three-body reaction . The is mainly produced in the forward hemisphere (direction of the incident K?). The lifetime is measured to be τ = (0.75 +0.14?0.11 × 10?10 sec substantially less than the Particle Data Group value of (1.3 ?0.3+0.2) × 10?10 sec. The mass is determined to be 1671.7 ± 0.6 MeV, in good agreement with other determinations. The decay asymmetry parameter α (for the decay mode ) is found to be ?0.2 ± 0.4. 相似文献