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51.
Alla Zablotskaya Izolda Segal Yuris Popelis Edmunds Lukevics Shipra Baluja Irina Shestakova Ilona Domracheva 《应用有机金属化学》2006,20(11):721-728
A series of triorganylsilyl(β‐dialkylaminoethoxy)silanes was prepared and characterized by elemental analysis, 1H, 13C, 29Si NMR and mass spectroscopy. Comparative study of 29Si resonance of newly synthesized compounds showed correlation between its value and substituent nature at the silicon atom, and is shifted upfield for β‐triorganyl(N,N‐dialkylaminoethoxy)silanes in comparison with corresponding methiodides, revealing weak N…Si interaction for proper silanes. In vitro antitumour and antimicrobial properties were investigated. The biological activity data exhibited a marked enhancement of inhibitory activity on trialkylsilylation against tumour cell lines and all the test bacterial/fungal strains. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
52.
Finite-size scaling of the order parameter O in the disordered phase is presented for percolation in 2d and 3d and compared to the behavior of the magnetization of the Ising model. We find that the order parameter O grows logarithmically with the system size L for p < pc and thus the analogy with the Ising model is not complete. Furthermore we find evidence for scaling behavior of the type O ~ L?y/v (pc ? p)β?y where the exponent y is not dv/2 as in the Is ing case. 相似文献
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56.
On estimating the performance of automatic optimization systems in steady-state operating modes 总被引:1,自引:0,他引:1
K. K. Sedova 《Radiophysics and Quantum Electronics》1972,15(3):314-319
Using the example of the investigation of a relay difference automatic optimization system, the author discusses and approves a new procedure for estimating the performance of sample-data systems having constant-area control pulses in steady-state operating modes.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 15, No. 3, pp. 419–426, March, 1972. 相似文献
57.
Stishov SM Petrova AE Shikov AA Lograsso TA Isaev EI Johansson B Daemen LL 《Physical review letters》2010,105(23):236403
The heat capacity of MnSi at B = 0 and B = 4 T was measured in the temperature range 2.5-100 K. To analyze the data, calculations of the phonon spectrum and phonon density of states in MnSi were performed. The calculated phonon frequencies were confirmed by means of inelastic neutron scattering. The analysis of the data suggests the existence of negative contributions to the heat capacity and entropy of MnSi at T > T(c) that may imply a specific ordering in the spin subsystem in the paramagnetic phase of MnSi. 相似文献
58.
In the present paper we consider and study numerically two systems based on model FitzHugh–Nagumo neurons, where in the presence of periodic modulation of parameters it is possible to implement chaotic dynamics on the attractor in the form of a Smale–Williams solenoid in the stroboscopic Poincaré map. In particular, hyperbolic chaos characterized by structural stability occurs in a single neuron supplemented by a time-delay feedback loop with a quadratic nonlinear element. 相似文献
59.
Konstantin Chernyshov Dmitry Gen Yuri Shemouratov Kirill Prokhorov Gulnara Nikolaeva Elena Sagitova Pavel Pashinin Anton Kovalchuk Alla Klyamkina Polina Nedorezova Boris Shklyaruk Valery Optov 《Macromolecular Symposia》2010,296(1):505-516
Nascent form of random copolymers of propylene with ethylene, 1-butene, 1-hexene, 1-octene, and 4-methyl-1-pentene was studied by Raman spectroscopy. The most significant spectral alterations with a change in propylene content were observed in two lines at 809 and 841 cm−1. The first line corresponds to vibrations of polypropylene helical chains in the crystalline phase, while the second one is associated with vibrations of polypropylene helical chains having isomeric defects. Raman data confirm that conformational composition and phase state of copolymer macromolecules strongly depend on the comonomer content as well as on the size of the comonomer units. 相似文献
60.
Ivanna Yu. Danyliuk Ruslan I. Vas’kevich Alla I. Vas'kevich Eduard B. Rusanov Mykhailo V. Vovk 《Phosphorus, sulfur, and silicon and the related elements》2019,194(1-2):156-162
Heterocyclization of N-(pyrazol-3-yl)styrylacetamides with arenesulfenyl chlorides yields the corresponding tetrahydrofuran-2-iminium perchlorates isolable after chromatography as trans-5-aryl-4-(arylthio)tetrahydrofuran-2-ones and 5-aryl-4-(arylthio)-1-(pyrazol-3-yl)pyrrolidin-2-ones, with the latter predominating. N-(Pyrazol-4-yl)styrylacetamides react under analogous conditions to give 5-aryl-4-(arylthio)-1-(pyrazol-4-yl)pyrrolidin-2-ones, 4-aryl-3-(arylthio)-4-chloro-N-(1-methylpyrazol-4-yl)butanamides, and tetrahydrofuran-2-iminium perchlorates which, when chromatographed, produce 5-aryl-4-(arylthio)dihydrofuran-2(3H)-ones and 4-aryl-3-(arylthio)-4-methoxy-N-(1-methyl-1H-pyrazol-4-yl)butanamides. 相似文献