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81.
Yaroslavov AA Sybachin AV Kesselman E Schmidt J Talmon Y Rizvi SA Menger FM 《Journal of the American Chemical Society》2011,133(9):2881-2883
Cryo-TEM and NaCl-leakage experiments demonstrated that the cationic polymer polylysine induces fusion of anionic liposomes but that the cationic polymer poly(N-ethyl-4-vinylpyridinium bromide) (PEVP) does not, although both polymers bind strongly to the liposomes. The difference was traced to the thickness of the coatings at constant charge coverage. Polylysine is believed to form planar β-sheets that are sufficiently thin to allow membrane fusion. In contrast, looping and disorganization among adsorbed PEVP molecules physically prevent fusion. A similar effect is likely to be applicable to important polycation-induced fusion of cell membranes. 相似文献
82.
We introduce the notion of 𝒦-nonsingularity of a module and show that the class of 𝒦-nonsingular modules properly contains the classes of nonsingular modules and of polyform modules. A necessary and sufficient condition is provided to ensure that this property is preserved under direct sums. Connections of 𝒦-nonsingular modules to their endomorphism rings are investigated. Rings for which all modules are 𝒦-nonsingular are precisely determined. Applications include a type theory decomposition for 𝒦-nonsingular extending modules and internal characterizations for 𝒦-nonsingular continuous modules which are of type I, type II, and type III, respectively. 相似文献
83.
In this paper, we consider a generalized mixed equilibrium problem in real Hilbert space. Using the auxiliary principle, we define a class of resolvent mappings. Further, using fixed point and resolvent methods, we give some iterative algorithms for solving generalized mixed equilibrium problem. Furthermore, we prove that the sequences generated by iterative algorithms converge weakly to the solution of generalized mixed equilibrium problem. These results require monotonicity (θ-pseudo monotonicity) and continuity (Lipschitz continuity) for mappings. 相似文献
84.
F. K. Amanuel B. Zelalem A. K. Chaubey Avinash Agarwal I. A. Rizvi Anjana Maheshwari Tauseef Ahmed 《The European Physical Journal A - Hadrons and Nuclei》2011,47(12):156
In this paper, we present the results of our investigation of reaction dynamics leading to incomplete fusion of heavy ions
at moderate excitation energies, especially the influence of incomplete fusion on complete fusion of 12C -induced reactions at specific energies ≈ 4–7.2M eV/nucleon. Excitation functions of various reaction products populated
via complete and/or incomplete fusions of a 12C projectile with 93Nb, 59Co and 52Cr targets were measured at several specific energies ≈ 4–7.2 MeV/nucleon, using a recoil catcher technique, followed by off-line
γ-ray spectrometry. The measured excitation functions were compared with theoretical values obtained using the PACE4 statistical
model code. For representative non-α-emitting channels in the 12C + 93Nb system, the experimentally measured excitation functions were, in general, found to be in good agreement with the theoretical
predictions. However, for α-emitting channels in the 12C + 93Nb, 12C + 59Co, and 12C + 52Cr systems, the measured excitation functions were higher than the predictions of the theoretical model code, which may be
credited to incomplete fusion reactions at these energies. An attempt was made to estimate the incomplete fusion fraction
for the present systems, which revealed that the fraction was sensitive to the projectile energy and mass asymmetry of the
entrance channel. 相似文献
85.
86.
Interfacial wave propagation parallel to a dielectric interface has been studied by considering an electric current line source
present at the interface. The first order asymptotic evaluation of field components shows a null of the electric field at
the interface. An amplitude null represents an unstable structure in the phase map and a phase front discontinuity across
the interface. Higher order asymptotic evaluation has been employed to gain further insight into this propagation problem.
The results show that the wavefronts need not be discontinuous. The continuity of the phase fronts is preserved with the help
of interesting and stable structures such as saddle points and center points in the phase map of the electric field in both
half spaces.
相似文献
87.
88.
In this article, non‐linear propagation of ingoing and outgoing electrostatic waves on the ion time scale in an unmagnetized, non‐relativistic electron‐ion (ei) plasma in the presence of warm ions, ion kinematic viscosity, and trapped Maxwellian electrons was examined in a non‐planar geometry. In the weak non‐linearity limit, modified soliton and shock equations were derived with the inclusion of electron trapping in cylindrical and spherical geometries. The finite difference method was used to solve all these equations in the non‐planar geometries using the planar versions of these equations as an initial input. The results were compared with their counterparts with quadratic non‐linearity and the main differences were expounded. It was shown that the spatio‐temporal scales over which the shocks form for the non‐planar trapped Burgers equation are much shorter by comparison with the shocks admitted by the non‐planar trapped Korteweg de Vries Burgers equation. It was also found that unlike their non‐linear shock counterparts, the solitary structures admitted by the non‐planar trapped Korteweg de Vries equation exhibit a phase shift. 相似文献
89.
Kalim U. Tariq Aly R. Seadawy Muhammad Younis S. T. R. Rizvi 《Optical and Quantum Electronics》2018,50(3):147
In this article, some new traveling wave solutions to the space–time fractional equal-width equation are constructed with the help of the extended Fan sub-equation method. A simple transformation is introduced to convert the fractional order partial differential equation into an ordinary differential equation. As a result, the bright, dark, singular and combined wave solitons are observed for different values of two parameters. Moreover, the graphical representations are also depicted. 相似文献
90.
Summary Tropolone forms a water-soluble yellow complex with rhodium-(III), which is extractable into chloroform containing pyridine. Although max of the complex lies at 390 nm, the more suitable wave-length for the determination is 420 nm at which there is practically no absorption by the reagent. The composition of the complex, as determined by Job's and logarithmic methods, comes out to be 1 2. The pH range for maximum colour development is 5.5–6.3. Beer's law is followed up to 9.0 ppm and sensitivity of the colour reaction at 420 nm is 0.009g Rh/cm2. The effect of various foreign ions has been investigated. With simple modifications, the method becomes highly selective.
Zusammenfassung Tropolon (Cykloheptatrienolon) bildet mit Rhodium(III) eine gelbe, wasserlösliche Komplexverbindung, die sich mit pyridinhältigem Chloroform extrahieren läßt. Das Absorptionsmaximum liegt zwar bei 390 nm, aber für die Messung eignet sich die Wellenlänge 420 nm besser, die von dem Reagens selbst praktisch nicht absorbiert wird. Die Zusammensetzung des Komplexes wurde nachJob und nach logarithmischen Methoden bestimmt und entspricht dem Verhältnis 1 2. Maximale Farbintensität wird bei pH 5,5–6,3 erreicht. Das Beer'sche Gesetz ist bis 9,0 ppm gültig, die Empfindlichkeit bei 420 nm entspricht 0,009g Rh/cm2. Der Einfluß verschiedener Fremdionen wurde untersucht. Mit einfachen Vorkehrungen wird die Methode hoch selektiv.相似文献