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101.
Any unitary irreducible representation π of a Lie group G defines a moment set Iπ, subset of the dual g? of the Lie algebra of G. Unfortunately, Iπ does not characterize π. If G is exponential, there exists an overgroup G+ of G, built using real-analytic functions on g?, and extensions π+ of any generic representation π to G+ such that Iπ+ characterizes π.In this paper, we prove that, for many different classes of group G, G admits a quadratic overgroup: such an overgroup is built with the only use of linear and quadratic functions.  相似文献   
102.
The kinetics of the solvolytic aquation of trans-[Ru (3-Me Py)4Cl2] was studied spectrophotometrically in water – isopropanol in the range (30–90% v/v), and water acetonitrile in the range (10–70% v/v), and in the temperature range 50–65 °C. Plots of log k versus the reciprocal of the relative permittivity and Grunwald–Winstien gave non-linear plots. This non-linearity is derived from a large differential effect of solvent structure between the initial and transition states. The plot of log k versus water concentration was also non linear; evidence for the presence of a S N 1 mechanism. However, extrema in the variation of enthalpy ΔH* and entropy ΔS* of activation correlate well with the extrema in physical properties of the mixtures which are related to changes in solvent structure. Linear plots of ΔH* versus ΔS* were obtained and the iso- kinetic temperature indicates that the reaction is entropy controlled.  相似文献   
103.
The sulfamide functional group is increasingly relevant in both medicinal and bioorganic chemistry. We report here practical access to a series of N2,N5-substituted five-membered cyclosulfamides. The five-membered heterocyclic motif was prepared starting from proteogenic amino acids and chlorosulfonyl isocyanate via the Mitsunobu reaction. Selected chemical and spectral proprieties and the antimicrobial evaluation of these compounds are detailed.  相似文献   
104.
The only therapy for coeliac disease patients is to completely avoid foods containing gluten, a protein complex common in several small-grain cereals. However, many alternative gluten-free foods available on the market present nutritional deficiencies. Therefore, the aim of this research was to evaluate the composition and the antioxidant properties of gluten-free pasta enriched with 10% or 15% of tomato waste or linseed meal, two food industry by-products. The traits analysed were protein, lipid, ash and fibre content, heat damage, tocols, carotenoids and phenolics composition (by HPLC), antioxidant capacity, and pasta fracturability. The enriched pastas contained more fibre and lipids than the control, while the protein and ash values were similar. The addition of tomato and linseed waste improved tocols concentration but had no effect on carotenoids content. The free soluble polyphenols increase was similar for both by-products and proportional to the enrichment percentage, while the bound insoluble polyphenols were higher in linseed-enriched pastas. The samples with linseed meal showed the greatest antioxidant capacity and, at 10% addition, the highest fracturability value. In conclusion, the addition of tomato and linseed by-products significantly increases the presence of bioactive compounds (particularly polyphenols), improving the nutritional value of gluten-free pasta.  相似文献   
105.
The kinetics of amide bond cleavage in p-chloro and p-bromo oxazolinone have been studied using triethylamine as a base catalyst under pseudo-first order conditions, in the temperature range (303.15?C333.15?K). The reaction rate was measured spectrophotometrically over a range of acetonitrile?Cwater mixed solvent (30?C70?%, v/v) compositions. The reaction rate was found to be faster for p-Cl than for p-Br oxazolinone. The thermodynamic parameters of activation were calculated: ?G* increased gradually as the mole fraction of the cosolvent increased due to quasi-mirror image compensation of ?H* and ?S* (entropy?Centhalpy compensation). The isokinetic temperature indicates that the reaction is enthalpy controlled. The reactivity was analyzed in the light of various simple and multiple regression equations using the Kamlet?CTaft solvatochromic parameters.  相似文献   
106.
In a two-phase (liquid–gas) two-component (water–hydrogen) system we discuss the formulation of the possible dissolution of hydrogen in the liquid phase. We show how Henry’s law fits in a phase diagram and the problem is formulated as a set of nonlinear partial differential equations with complementarity constraints.  相似文献   
107.
The crystal compound [N (CH3)4]2PdCl4 was crystallized in the orthogonal system and the space group is P4/mmm and the refined unit cell parameters are a = b = 8.831 Å, c = 11.415 Å. The structure, vibrational spectra and optical properties have been investigated. DSC studies indicate the presence of two phase transitions at higher temperature which confirm the thermal stability of the palladium-based compound. These transitions have been studied by Raman scattering on single crystals as a function of temperature which confirmed their nature. The assignment of the observed bands is discussed based in the theoretical calculated frequencies by the density functional theory (DFT) method using B3LYP/LanL2DZ basis in the GAUSSIAN-09 package of programs. The optical properties in the UV–visible region have been deduced and the energy gap has been determined which is equal to 3.11 eV.  相似文献   
108.
[N(C2H5)4]2Pd2Cl6 hybrid compound with semiconducting character was synthetized and characterized by X-ray diffraction, the thermal, optical and electrical properties. X-ray diffraction indicates that the compound crystallize at room temperature in the orthorhombic system and (Immm) space group. Two endothermic peaks at, 343 K and 440 K were observed in the DSC measurements corresponding to the evaporation of water molecules and order-disorder transition, respectively. The optical band gap (Eg = 4.34 eV) was deduced by the Tauc relation. The electrical properties was studied using the impedance spectroscopy in the frequency range of 0.1 Hz to 1 MHz and over the temperature range of 270 K to 480 K. The analysis of Nyquist plots revealed the presence of grains, grain boundaries and the electrode effects. The equivalent circuit was determined. The Ac conductivity was analyzed by the Jonsher low and the conduction mechanism was deduced based in the Elliot theory and indicate that the correlated barrier hopping model (CBH) was described the two regions II and IV and the overlapping polaron model (OLPT) the right model described the conduction in the regions I and III.  相似文献   
109.
A novel series of 26 substituted N-(2-ethylphenyl)-2-oxo-pyridine-3-carbonitriles have been designed and synthesized via one-pot synthesis of various aromatic aldehydes, different aromatic acetophenones, and 2-cyano-N-(2-ethylphenyl)acetamide 1 . Moreover, cytotoxicity of the target compounds was evaluated by NCI, which selected 14 compounds for one-dose screening. Among them, compound 21 was selected for five-dose screening, which confirmed its potency against most of cancer cell lines. This compound elicited selectivity profile against human cell line WI-38. Cell cycle analysis was carried out, revealed that compound 21 is an apoptosis inducer causing cell cycle arrest at G2/M. Further exploration on the mode of action by evaluating its effect against Pim-1, Pim-2, and Pim-3 demonstrated its inhibitory effect on Pim-1 and Pim-3 rather than Pim-2. Molecular docking showed that compound 21 binds with high affinity to the active site of Pim-1 enzyme through three hydrogen bonds and two arene-H bonds.  相似文献   
110.
A satellite in the form of a system of bodies that does not have the property of a gyrostat in the general case is considered. An algorithm for determining all the equilibrium configurations of the system that correspond to steady motions in a central gravitational field and an algorithm for analysing their stability are given. A method based on Routh's first theorem is used to investigate the asymptotic stability of the steady motions in the unconstrained problem. Three effects caused by internal dissipation are established in a model example: stabilization of the satellites in a neighbourhood of rotations about a normal to the orbital plane, which is codirectional with the axis of the largest moment of inertia, evolution of elliptic orbits into circular orbits, and capture of the satellites in resonant oscillatory modes of motion.  相似文献   
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