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101.
Md. Irshad Alam Aquil ur‐Rahim Siddiqui Nazia Khanam Shaikh Jalil Kamaruddin 《Journal of separation science》2020,43(18):3597-3606
An innovative high‐performance liquid chromatography assay method was developed and validated for quantification of dextromethorphan hydrobromide and desloratadine simultaneously in monophasic liquid formulation by preparing syrup containing 30 mg/5 mL of dextromethorphan hydrobromide and 1.2 mg/mL of desloratadine. The chromatographic severance was executed by gradient solution A and B. The composition of buffer solution A contained 0.05 M monobasic potassium, then 1 mL triethylamine was added to it and the pH was adjusted to 2.3 with orthophosphoric acid. Methanol was used as solution B. The gradient elution was executed with Kromasil C8 (250 mm × 4.6 mm) column having 1.5 mL/min flow rate and 20 µL injection volume with UV‐estimation at 254 nm for dextromethorphan hydrobromide and DES. The present research was planned according to Box‐Behnken design by utilizing design expert software, using four factors such as column temperature (A), flow rate (B), mobile phase–organic phase (C), and pH (D); correspondingly the selected response variables were resolution between A and B, that is, desloratadine and methyl paraben (Y1), tailing of dextromethorphan hydrobromide (Y2), and tailing of desloratadine (Y3). The parameters such as system suitability, linearity, accuracy, precision, robustness, limit of detection, limit of quantitation, and ruggedness were analyzed to validate the developed method in accordance with current regulatory guidelines. 相似文献
102.
Resveratrol, the red-wine polyphenol, is intensively studied polyphenols for its pleiotropic biological effects. A plethora of health beneficial effects of this stilbene has been reported including cardio-protective, neuro-protective, anti-cancer, anti-diabetic and interesting anti-aging. Though it has been proposed that these effects of resveratrol arise from its capacity to interact with multiple molecular targets involved in diverse intracellular pathways including activation of sirtuins, the antioxidant property of this compound is the most described one to attribute its diverse health beneficial effects. In the present review we have explained the biological activities of resveratrol with the latest laboratory evidences towards its antioxidant effects. 相似文献
103.
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
104.
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
105.
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
106.
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
107.
108.
109.
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
110.