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Abstract  

We discuss determination of jumps for functions with generalized bounded variation. The questions are motivated by A. Gelb and E. Tadmor [1], F. M�ricz [5] and [6] and Q. L. Shi and X. L. Shi [7]. Corollary 1 improves the results proved in B. I. Golubov [2] and G. Kvernadze [3].

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Abstract

We prove that the conjugate convolution operators can be used to calculate jumps for functions. Our results generalize the theorems established by He and Shi. Furthermore, by using Lukács and Móricz's idea, we solve an open question posed by Shi and Hu.

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Abstract  

A characterization formula of an orthonormal multiwavelet with di_erent real dilations and translations for L E 2(R) is presented. The result includes the known result on the classical Hardy space H 2(R).

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Abstract  

The effect of glucose (0–15 mass%) on the kinetics of bovine serum albumin (BSA) denatured aggregation at high concentration in aqueous solution has been studied by differential scanning calorimetry. The observed denatured aggregation process was irreversible and could be characterized by a denaturation temperature (T m), apparent activation energy (E a), the approximate order of reaction, and pre-exponential factor (A). As the glucose concentration increased from 0 to 15 mass%, T m increased, E a also increased from 514.59409±6.61489 to 548.48611±7.81302 kJ mol−1, and A/s−1 increased from 1.24239E79 to 5.59975E83. The stabilization increased with an increasing concentration of glucose, which was attributed to its ability to alter protein denatured aggregation kinetics. The kinetic analysis was carried out using a composite procedure involving the iso-conversional method and the master plots method. The iso-conversional method indicated that denatured aggregation of BSA in the presence and absence of glucose should conform to single reaction model. The master plots method suggested that the simple order reaction model best describe the process. This study shows the combination of iso-conversional method and the master plots method can be used to quantitatively model the denatured aggregation mechanism of the BSA in the presence and absence of glucose.

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Abstract  

A complex of neodymium perchloric acid coordinated with L-glutamic acid and imidazole, [Nd(Glu)(H2O)5(Im)3](ClO4)6·2H2O was synthesized and characterized by IR and elements analysis for the first time. The thermodynamic properties of the complex were studied with an automatic adiabatic calorimeter and differential scanning calorimetry (DSC). Glass transition and phase transition were discovered at 221.83 and 245.45 K, respectively. The glass transition was interpreted as a freezing-in phenomenon of the reorientational motion of ClO4 ions and the phase transition was attributed to the orientational order/disorder process of ClO4 ions. The heat capacities of the complex were measured with the automatic adiabatic calorimeter and the thermodynamic functions [H T-H 298.15] and [S T-S 298.15] were derived in the temperature range from 80 to 390 K with temperature interval of 5 K. Thermal decomposition behavior of the complex in nitrogen atmosphere was studied by thermogravimetric (TG) analysis and differential scanning calorimetry (DSC).

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Summary

Supercritical fluid extraction (SFE) was used to extract shionone from Aster tataricus L. f. The effect of various parameters, i.e., temperature, pressure and sample particle size on yield was investigated with an analytical-scale SFE system to find the optimal conditions. The process was then scaled up by 50 times with a preparative SFE system under the optimized conditions of temperature 40 °C, pressure 30 MPa, and a sample particle size of 40–60 mesh. Then preparative high-speed counter-current chromatography was successfully used for isolation and purification of shionone from the SFE extract with a two-phase solvent system composed of n-hexane-methanol (2:1, volume ratio). The separation produced a total of 75 mg of shionone from 500 mg of the crude extract in one step separation with the purity of 98.7%, respectively, as determined by high-performance liquid chromatography (HPLC) and 92% recovery. The structure of shionone was identified by electrospray ionization-mass spectrometry (ESI-MS), hydrogen-1 nuclear magnetic resonance (1H-NMR), and carbon-13 nuclear magnetic resonance (13C-NMR).

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Abstract

By using the critical point theory, the existence of periodic solutions to second order nonlinear p-Laplacian difference equations is obtained. The main approach used is a variational technique and the saddle point theorem. The problem is to solve the existence of periodic solutions of second order nonlinear p-Laplacian difference equations.

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Abstract  

The solid complexes of Cr(NO3)3 with L-α-amino acids (AA=Val, Leu, Thr, Arg, Phe and Try) have been prepared in 95% alcoholic, the compositions of which were identified as the general formula Cr(AA)2(NO3)32H2O by elemental and chemical analyses. The bonding characteristics of the title complexes were characterized by IR, indicating that nitrogen and oxygen atoms in the ligands coordinated to Cr3+ in a bidentate fashion. With the aid of TG-DTG and IR techniques, the complexes were subjected to thermal decomposition in an atmosphere of oxygen, presuming that the decompositions of the complexes consist of two steps and the complexes were decomposed into chromium hemitrioxide after undergoing dehydration and skeleton splitting of the complexes. The constant volume energies of combustion of the complexes were determined by a RBC-P type rotating-bomb calorimeter. According to Hess's law, the standard enthalpies of formation of the complexes were calculated as (-1831.404.40), (-2542.036.13), (-1723.813.99), (-2224.313.02), (-2911.616.53) and (-659.327.42) kJ mol-1, respectively.

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Abstract  

Solid complexes of M(His)2Cl2 nH2O (M=Mn, Co, Ni, Cu) of MnCl26H2O, CoCl26H2O, NiCl26H2O, CuCl22H2O and L-α-histidine (His) have been prepared in 95% ethanol solution and characterized by elemental analyses, chemical analyses, IR and TG-DTG. The constant-volume combustion energies of the complexes have been determined by a rotating-bomb calorimeter. And the standard enthalpies of formation of the complexes have been calculated as well.

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Abstract  

A novel solid complex, formulated as Ho(PDC)3 (o-phen), has been obtained from the reaction of hydrate holmium chloride, ammonium pyrrolidinedithiocarbamate (APDC) and 1,10-phenanthroline (o-phenH2O) in absolute ethanol, which was characterized by elemental analysis, TG-DTG and IR spectrum. The enthalpy change of the reaction of complex formation from a solution of the reagents, Δr H m θ (sol), and the molar heat capacity of the complex, c m, were determined as being –19.1610.051 kJ mol–1 and 79.2641.218 J mol–1 K–1 at 298.15 K by using an RD-496 III heat conduction microcalorimeter. The enthalpy change of complex formation from the reaction of the reagents in the solid phase, Δr H m θ(s), was calculated as being (23.9810.339) kJ mol–1 on the basis of an appropriate thermochemical cycle and other auxiliary thermodynamic data. The thermodynamics of reaction of formation of the complex was investigated by the reaction in solution at the temperature range of 292.15–301.15 K. The constant-volume combustion energy of the complex, Δc U, was determined as being –16788.467.74 kJ mol–1 by an RBC-II type rotating-bomb calorimeter at 298.15 K. Its standard enthalpy of combustion, Δc H m θ, and standard enthalpy of formation, Δf H m θ, were calculated to be –16803.957.74 and –1115.428.94 kJ mol–1, respectively.

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