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排序方式: 共有915条查询结果,搜索用时 0 毫秒
1.
The effects of a biquadratic exchange and an external magnetic field on the phase states of a twodimensional non-Heisenberg ferromagnet have been studied with allowance for magnetoelastic and magnetodipolar interactions. 相似文献
2.
The structure of the nonlinear H∞-filter in the neighborhood of the estimated trajectory is investigated and a bound on the size of the neighborhood that allows this structure is determined, both for finite and infinite horizons. Riccati inequalities that depend on the estimated trajectory are derived for finding the filter gain matrix and an algorithm for calculating the bound on the size of the above neighborhood is presented. Explicit formulas are obtained in the infinite horizon case for the minimum achievable disturbance attenuation level, the size of the neighborhood, and the corresponding filter gain. 相似文献
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6.
Emilia Nowaczyk 《Electrical Engineering (Archiv fur Elektrotechnik)》2007,89(5):419-424
The paper presents the results of investigations into several methods of calculating the active power value from current and
voltage signal samples. The accuracy attainable for nonsinusoidal signals whose frequency differs from the nominal one was
determined. A new active power calculation method ensuring accurate results for sampling over two signal periods is proposed.
The method uses a very simple computing algorithm. 相似文献
7.
A. Ya. Fridman E. M. Morozova A. Yu. Tsivadze N. P. Sokolova I. I. Bardyshev A. M. Gorbunov O. P. Shapokhina 《Protection of Metals》2007,43(5):454-458
With the aim of classifying PVC materials in which surface layers are converted into interpenetrated network cyclam nanofilms
among polymer-polymer systems, comparative studies of their properties were carried out with consideration for the specific
conditions for the preparation of the material. The density and structures of near-surface layers, the bulk ratio of the ordered
and disordered forms, the dynamics of swelling in water, and the effective partial volume occupied by water molecules were
studied for PVC plates prior to and after hydrothermal treatment. The conversion of the surface layers changes the structural
self-organization of PVC: the polymer structure becomes more compact and ordered both in the area adjacent to the nanofilm
and in the polymer bulk, which is characteristic of systems of the type “hard coating on soft substrate”.
Original Russian Text ? A.Ya. Fridman, E.M. Morozova, A.Yu. Tsivadze, N.P. Sokolova, I.I. Bardyshev, A.M. Gorbunov, O.P. Shapokhina,
2007, published in Zashchita Metallov, 2007, Vol. 43, No. 5, pp. 498–502. 相似文献
8.
Emilia Piosik Marta Ziegler-Borowska Dorota Cheminiak-Dudkiewicz Tomasz Martyski 《International journal of molecular sciences》2021,22(5)
An adsorption process of magnetite nanoparticles functionalized with aminated chitosan (Fe3O4-AChit) showing application potential in nanomedicine into cell membrane models was studied. The cell membrane models were formed using a Langmuir technique from three selected phospholipids with different polar head-groups as well as length and carbon saturation of alkyl chains. The research presented in this work reveals the existence of membrane model composition-dependent regulation of phospholipid-nanoparticle interactions. The influence of the positively charged Fe3O4-AChit nanoparticles on a Langmuir film stability, phase state, and textures is much greater in the case of these formed by negatively charged 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DPPG) than those created by zwitterionic 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC). The adsorption kinetics recorded during penetration experiments show that this effect is caused by the strongest adsorption of the investigated nanoparticles into the DPPG monolayer driven very likely by the electrostatic attraction. The differences in the adsorption strength of the Fe3O4-AChit nanoparticles into the Langmuir films formed by the phosphatidylcholines were also observed. The nanoparticles adsorbed more easily into more loosely packed POPC monolayer. 相似文献
9.
Anita Romanowska Katarzyna Wgrzyn Katarzyna Bury Emilia Sikorska Aleksandra Gnatek Agnieszka Piwkowska Igor Konieczny Adam Lesner Magdalena Wysocka 《International journal of molecular sciences》2021,22(5)
The present study aimed to synthesize novel polycationic polymers composed of N-substituted L-2,3-diaminopropionic acid residues (DAPEGs) and investigate their cell permeability, cytotoxicity, and DNA-binding ability. The most efficient cell membrane-penetrating compounds (O2Oc-Dap(GO2)n-O2Oc-NH2, where n = 4, 6, and 8) showed dsDNA binding with a binding constant in the micromolar range (0.3, 3.4, and 0.19 µM, respectively) and were not cytotoxic to HB2 and MDA-MB-231 cells. Selected compounds used in the transfection of a GFP plasmid showed high transfection efficacy and minimal cytotoxicity. Their interaction with plasmid DNA and the increasing length of the main chain of tested compounds strongly influenced the organization and shape of the flower-like nanostructures formed, which were unique for 5/6-FAM-O2Oc-[Dap(GO2)]8-O2Oc-NH2 and typical for large proteins. 相似文献
10.
Fernando Corvillo Laura Gonzlez-Snchez Alberto Lpez-Lera Emilia Arjona Giovanni Ceccarini Ferruccio Santini David Araújo-Vilar Rebecca J Brown Joan Villarroya Francesc Villarroya Santiago Rodríguez de Crdoba Teresa Caballero Pilar Nozal Margarita Lpez-Trascasa 《International journal of molecular sciences》2021,22(12)