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121.
Molecular Diversity - Wnt signaling pathway is an evolutionarily conserved pathway responsible for neurogenesis, axon outgrowth, neuronal polarity, synapse formation, and maintenance....  相似文献   
122.
An evaporative light scattering detection (ELSD) based high-performance liquid chromatography (HPLC) method is developed for the determination of polysorbate 80 (tween 80) in therapeutic protein formulations. The method is simple and overcomes the difficulties associated with specificity and sensitivity. The method is suitable for the quantitation of polysorbate 80 in the usual formulation range (0.01-0.1%) as well as in trace amounts ≥13 μg/mL. The analysis is based on the removal of protein first by solid-phase extraction using Oasis HLB cartridges followed by HPLC analysis using Inertsil ODS-3 C 18 column (4.6×150 mm, 5 μm) using reversed-phase conditions. The detector response changes exponentially with an increase in polysorbate concentration. A very good linear fit of log ELSD response against log polysorbate 80 concentration is observed. The specificity, sensitivity, precision, and accuracy of the method are suitable for the quantitation of polysorbate 80 in protein formulations.  相似文献   
123.
A medium modified gluon propagator is used to evaluate the scattering cross section for the process gggg in the QCD medium by performing an explicit sum over the polarizations of the gluons. We incorporate a magnetic screening mass from a non-perturbative study. It is shown that the medium modified cross section is finite, divergence free, and is independent of any ad-hoc momentum transfer cut-off parameters. The medium modified finite cross sections are necessary for a realistic investigation of the production and equilibration of the minijet plasma expected at RHIC and LHC.  相似文献   
124.
Effective atomic numbers (Zeff) of three polymers, an alloy, a compound and an element have been determined for photoelectric process at 59.54 keV from the accurately measured total attenuation coefficients, for γ ray attenuation. Possible conclusions are drawn on electron binding effects and K-edge effects.  相似文献   
125.
The kinetics of thermal polymerization of methyl methacrylate initiated by the redox system Mn(III)–glycerol was studied in aqueous sulfuric acid in the temperature range of 30–40°C, and the rates of polymerization, Rp, and Mn3+ disappearance, etc., were measured. The effect of certain water-miscible organic solvents and certain cationic and anionic surfactants on the rates of polymerization has been investigated. A mechanism involving the formation of a complex between Mn3+ and glycerol whose decomposition yields the initiating free radical with the polymerization being terminated by the metal ion has been suggested.  相似文献   
126.
The thermal stability of some boracites, CuB7O13Cl, NiB7O13Br and FeB7O13I, was investigated using thermogravimetry in air up to 1000°, DTA in air to 1200° and evolved gas analysis in vacuum to 1200°C. Only the FeI compound showed weight loss below 1000°C. The endothermic peaks associated with melting were CuCl (1025°C), NiBr (1150°C) and FeI) (965°C). Evolved gas analysis indicated major differences in the decomposition products of the three materials.  相似文献   
127.
A simple and rapid spectrophotometric method for the determination of six phenothiazines can be based on the formation of a coloured compound between molybdophosphoric acid and phenothiazines. The i.r. and e.s.r. spectra of the coloured compounds showed that molybdophosphoric acid oxidizes phenothiazines to a radical cation with which it then forms a coloured compound. The proposed method is employed for the determination of phenothiazines in pharmaceutical preparations. Calibration graphs are linear over ranges of about 100–2000 μg of the phenothiazine.  相似文献   
128.
The strength distributions of the giant monopole resonance (GMR) have been measured in the even-A Sn isotopes (A=112-124) with inelastic scattering of 400-MeV alpha particles in the angular range 0 degrees -8.5 degrees . We find that the experimentally observed GMR energies of the Sn isotopes are lower than the values predicted by theoretical calculations that reproduce the GMR energies in 208Pb and 90Zr very well. From the GMR data, a value of Ktau = -550 +/- 100 MeV is obtained for the asymmetry term in the nuclear incompressibility.  相似文献   
129.
130.
In this article, structural and electronic properties of MgH2 have been studied. The aim behind this study was to find out the ground state crystal structure of MgH2. For the purpose, density functional theory (DFT)-based full-potential linearized augmented plane wave (FP-LAPW) calculations have been performed in three different space groups: P42/mnm (α-MgH2), Pa3 (β-MgH2) and Pbcn (γ-MgH2). It has been found that the ground state structure of MgH2 is α-MgH2. The present study shows that α-MgH2 transforms into γ-MgH2 at a pressure of 0.41 GPa. After further increase in pressure, γ-MgH2 transforms into β-MgH2 at a pressure of 3.67 GPa. The obtained results are in good agreement with previously reported experimental data. In all the studied phases, the behavior of MgH2 is insulating and its optical conductivity is around 6.0 eV. The α-MgH2 and γ-MgH2 are anisotropic materials while β-MgH2 is isotropic in nature.  相似文献   
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