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71.
Nonlinear Dynamics - This work is based on the observation that the first Poincaré–Lyapunov constant is a quadratic function of the coefficients of the two-dimensional vector field at a... 相似文献
72.
Privalov Alexei F. Galitskaya Elena Sinitsyn Vitaly Vogel Michael 《Applied magnetic resonance》2020,51(2):145-153
Applied Magnetic Resonance - The isotope effect H → D on diffusion in proton-exchange membrane Nafion 212 is investigated using 1H and 2H nuclear magnetic resonance (NMR)... 相似文献
73.
Alexei R. Khokhlov Elena Yu. Kramarenko Elena E. Makhaeva Sergei G. Starodubtzev 《Macromolecular theory and simulations》1992,1(3):105-118
A very simple theory of swelling and collapse of weakly charged polyelectrolyte networks in the solution of an oppositely charged surfactant has been developed. The following contributions to the free energy were taken into account: free energy of volume interaction and of elastic deformation of the network chains, free energy connected with micelle formation and free energy of translational motion of all mobile ions in the system (translational entropy). Both the cases of a solution of charged surfactant and that of a mixed solution of charged and neutral surfactant components have been taken into account. It has been shown that the behaviour of the network depends on the total surfactant concentration in the system and corresponds to one of the three following regimes: At low concentration, micelles inside the network are not formed and the behaviour of the polymer network is similar to that of a network swelling in the solution of a lowmolecular-weight salt (regime 1). In the second regime, surfactant concentration inside the network exceeds the critical micelle concentration and micelles are formed; in this regime the network collapses because surfactant molecules, aggregated in micelles, cease to create “exerting” osmotic pressure in the network sample. In the third regime, at very high surfactant concentration, formation of additional micelles inside the network ceases, and the network dimensions coincide with those of the corresponding neutral network. 相似文献
74.
75.
Kinga Nawalany Aleksandra Rusin Mariusz Kpczyski Alexei Mikhailov Gabriela Kramer-Marek Mirosaw
nietura Jan Potowicz Zdzisaw Krawczyk Maria Nowakowska 《Journal of photochemistry and photobiology. B, Biology》2009,97(1):8-17
Two photosensitizing systems: (1) tetrakis(4-hydroxyphenyl)porphyrin (p-THPP) encapsulated in sterically stabilized liposomes (SSL) and (2) p-THPP functionalized by covalent attachment of poly(ethylene glycol) (p-THPP–PEG2000) were studied in vitro. The dark and photo cytotoxicity of these systems were evaluated on two cell lines: HCT 116, a human colorectal carcinoma cell line, and DU 145, a prostate cancer cell line and compared with these determined for free p-THPP. It was demonstrated that both encapsulation in liposomes as well as attachment of PEG chain result in pronounced reduction of the dark cytotoxicity of the parent porphyrin. The liposomal formulation showed higher than p-THPP–PEG2000 photocytotoxicity towards both cell lines used in the studies. 相似文献
76.
Classical molecular dynamics simulations have been performed for crystalline germanium with the aim to estimate the thermal
effects within the first three coordination shells and their influence on the single-scattering and multiple-scattering contributions
to the Ge K-edge extended x-ray absorption fine structure (EXAFS). 相似文献
77.
Alexei Borodin Mihail Poplavskyi Christopher D. Sinclair Roger Tribe Oleg Zaboronski 《Communications in Mathematical Physics》2016,346(3):1051-1055
We correct an error in Theorem 12 of the original article concerning the edge scaling limit of the law of real eigenvalues for the real Ginibre ensemble. 相似文献
78.
79.
Let be an oriented Jordan smooth curve and a diffeomorphism of onto itself which has an arbitrary nonempty set of periodic points. We prove criteria for one-sided invertibility of the binomial functional operator
wherea andb are continuous functions,I is the identity operator,W is the shift operator,Wf=fo, on a reflexive rearrangement-invariant spaceX() with Boyd indices
X
,
X
and Zippin indicesp
x,q
x satisfying inequalities
Partially supported by F.C.T. (Portugal) grant PRAXIS XXI/BPD/22006/99.Partially supported by CONCACYT (México) grant, Cátedra Patrimonial, No. 990017-EX., nivel II. 相似文献
80.
We consider a one-dimensional charge density wave insulator formed by umklapp processes in a quarter-filled band. The spectrum of the model consists of gapless, uncharged excitations carrying spin +/- 1/2 (spinons) and gapped, spinless excitations carrying charge -/+ signe/2 (solitons and antisolitons). We calculate the low-energy behavior of the single-electron Green's function at zero temperature. The spectral function exhibits a featureless scattering continuum of two solitons and many spinons. The theory predicts that the gap observed by angle resolved photoemission is twice the activation gap in the dc conductivity. We comment on possible applications to PrBa(2)Cu(3)O(7) and to the Bechgaard salts. 相似文献