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61.
Biodegradability and biocompatibility are two crucial prerequisites for a promising therapeutic vehicle. Herein, a novel biocompatible copolymer has been synthesized using glycogen and polylactide (PLA). Glycogen, a naturally occurring biopolymer has been functionalized by methacrylation. On the other hand, lactide has been polymerized through ring opening polymerization (ROP), initiated by hydroxyethyl methacrylate (HEMA) and catalyzed by tin (II) 2‐ethyl hexanoate. Finally, the synthesized two substrates (i.e., glycogen methacrylate and PLA‐HEMA) are covalently connected by free‐radical polymerization, initiated by AIBN. The structure of the developed copolymer has been confirmed using 1H and 13C NMR spectral analyses. The gel characteristics have been evaluated by rheological studies, while the morphological assessment has been investigated by FESEM analysis. In vitro cytocompatibility study reveals that the hydrogel (Gly‐co‐PLA) is biocompatible. The in vitro and in vivo release studies demonstrate the excellent pH‐sensitive control release profile of dual drugs: ornidazole and ofloxacin. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1697–1703  相似文献   
62.
The reactions of 2-(arylazo) anilines, HL (1) [where HL is 2-(ArN=N)C6H4NH2; Ar is C6H5 (for HL1, 1a) and p-MeC6H4 (for HL2, 1b); H of HL represents the proton of Ar which gets dissociated upon orthometalation] with RhCl3 in methanol afforded new orthometalated complexes of composition (L)(HL)Rh(III)Cl2 (2) and (L)(ArNH2)Rh(III)Cl2 (3). The anionic L- binds the metal in tridentate (C, N, N) manner in both the complexes, while HL and ArNH2 bind the metal of 2 and 3 in monodentate fashion through the amino nitrogen. The ArNH2 of 3 was formed in situ due to cleavage of azo (-N=N-) function of monodentate HL of 2. The scission of N=N has been authenticated.  相似文献   
63.
64.
Let m, n be two fixed positive integers and let R be a 2-torsion free prime ring, with Utumi quotient ring U and extended centroid C. We study the identity F(x m+n+1) = F(x)x m+n  + x m D(x)x n for x in a non-central Lie ideal of R, where both F and D are generalized derivations of R and then determine the relationship between the form of F and that of D. In particular the conclusions of the main theorem say that if D is the non-zero map in R, then R satisfies the standard identity s 4(x 1, . . . , x 4) and D is a usual derivation of R.  相似文献   
65.
In this paper we present a teleportation protocol by which the multitask of transfer of a two-qubit and two single-qubit quantum states is performed simultaneously with the help of a single entangled channel. The protocol is under the supervision of a controller. There are three pairs of senders and receivers who are connected among themselves along with the controller by a single entangled state. The teleportation protocol is perfect.  相似文献   
66.
We develop a scheme to construct the Hamiltonians of the lambda-, vee- and cascade-type three-level configurations using the generators of SU(3) group. It turns out that this approach provides a well-defined selection rule to give different Hamiltonians for each configuration. The lambda- and vee-type configurations are exactly solved with different initial conditions while taking the two-mode classical and quantized fields. For the classical field, it is shown that the Rabi oscillation of the lambda model is similar to that of the vee model and the dynamics of the vee model can be recovered from lambda model and vice versa simply by inversion. We then proceed to solve the quantized version of both models by introducing a novel Euler matrix formalism. It is shown that this dynamical symmetry exhibited in the Rabi oscillation of two configurations for the semiclassical models is completely destroyed on quantization of the field modes. The symmetry can be restored within the quantized models when both field modes are in the coherent states with large average photon number which is depicted through the collapse and revival of the Rabi oscillations.   相似文献   
67.
In this work, we have investigated the validity of the generalized second law of thermodynamics in logamediate and intermediate scenarios of the universe bounded by the Hubble, apparent, particle and event horizons using and without using first law of thermodynamics. We have observed that the GSL is valid for Hubble, apparent, particle and event horizons of the universe in the logamediate scenario of the universe using first law and without using first law. Similarly the GSL is valid for all horizons in the intermediate scenario of the universe using first law. Also in the intermediate scenario of the universe, the GSL is valid for Hubble, apparent and particle horizons but it breaks down whenever we consider the universe enveloped by the event horizon.  相似文献   
68.
Molecular Diversity - Transmembrane protease serine-2 (TMPRSS2) is a cell-surface protein expressed by epithelial cells of specific tissues including those in the aerodigestive tract. It helps the...  相似文献   
69.
The dynamics of fission has been formulated by generalising the asymptotic expansion of the Fokker-Planck equation in terms of the strength of the fluctuations where the diffusion coefficients depend on the stochastic variables explicitly. The prescission neutron multiplicities and mean kinetic energies of the evaporated neutrons have been calculated and compared with the respective experimental data over a wide range of excitation energy and compound nuclear mass. The mean and the variance of the total kinetic energies of the fission fragments have been calculated and compared with the experimental values. Received: 8 September 1999 / Revised version: 22 November 1999  相似文献   
70.
For a conformally flat metric ds2 = a2(η)(dη2 – dx2 – y2 – dz2) Vilenkin obtained the equation $$\frac{\partial }{{\partial _{\eta } }}\left[ {\frac{{a^2 \left( {\eta } \right)\dot y}}{{\sqrt {1 + y'^2 - \dot y^2 } }}} \right] = \frac{\partial }{{\partial _x }}\left[ {\frac{{a^2 \left( {\eta } \right)\dot y'}}{{\sqrt {1 + y'^2 - \dot y^2 } }}} \right]$$ for a cosmic string and gave some particular solutionsboth for a = const and a const. The present workcompletely solves the equation for a = const and extendthe work of Vilenkin for a ≠ const.  相似文献   
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