It is well known that work done on a material by conservative forces (electrical, mechanical, chemical) will increase the Gibbs Potential of the material. The increase in Gibbs Potential can be stored in the material ...It is well known that work done on a material by conservative forces (electrical, mechanical, chemical) will increase the Gibbs Potential of the material. The increase in Gibbs Potential can be stored in the material and is free/available to do work at some later time. However, it will be shown in this paper that while in this state of higher Gibbs potential, the material is metastable and the material will degrade spontaneously/naturally with time in an effort to reach a lower Gibbs Potential. A generalized Gibbs Potential Model is developed herein to better understand its impact on a materials degradation rate. Special attention will be given to dielectrics degradation.展开更多
The thermodynamic properties of linear protein solutions are discussed by a statistical me-chanics theory with a lattice model. The numerical results show that the Gibbs function of the solution decreases, and the pro...The thermodynamic properties of linear protein solutions are discussed by a statistical me-chanics theory with a lattice model. The numerical results show that the Gibbs function of the solution decreases, and the protein chemical potential is enhanced with increase of the protein concentration for dilute solutions. The influences of chain length and temperature on the Gibbs function of the solution as well as the protein chemical potential are analyzed.As an application of the theory, the chemical potentials of some mutants of type I antifreeze proteins are computed and discussed.展开更多
The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazo...The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazole compounds from carboxylic acids,amidines and hydrazines have been first investigated with the B3 LYP/6-311++G** method.According to the potential energy profile,it can be predicted that the course of the reaction consists of five reactions containing six elementary reactions.The α-imino-3-pyridine formic acid and acetamidine form first an intermediate product through a dehydration reaction; the intermediate product further combines with hydrogen ion to form a positive ion; the positive ion reacts with anisole hydrazine by a dehydration reaction to form another positive ion; then,followed by two isomerization reactions,the final reaction with the acetate ion(Ac-) produces the final product.The research results reveal the laws of synthesis reaction of 1,3,5-substituted-1,2,4-triazoles by the carboxylic acids,amidines,hydrazines and their derivatives on theoretical level.It provides the systemic theoretical basis for the synthesis,development and application of 1,3,5-substituted-1,2,4-triazole compounds.展开更多
文摘It is well known that work done on a material by conservative forces (electrical, mechanical, chemical) will increase the Gibbs Potential of the material. The increase in Gibbs Potential can be stored in the material and is free/available to do work at some later time. However, it will be shown in this paper that while in this state of higher Gibbs potential, the material is metastable and the material will degrade spontaneously/naturally with time in an effort to reach a lower Gibbs Potential. A generalized Gibbs Potential Model is developed herein to better understand its impact on a materials degradation rate. Special attention will be given to dielectrics degradation.
基金This work was supported by the National Natural Science Foundation of China (No.10764003 and No.30560039).
文摘The thermodynamic properties of linear protein solutions are discussed by a statistical me-chanics theory with a lattice model. The numerical results show that the Gibbs function of the solution decreases, and the protein chemical potential is enhanced with increase of the protein concentration for dilute solutions. The influences of chain length and temperature on the Gibbs function of the solution as well as the protein chemical potential are analyzed.As an application of the theory, the chemical potentials of some mutants of type I antifreeze proteins are computed and discussed.
基金supported by the National Natural Science Foundation of China(No.51102114)
文摘The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazole compounds from carboxylic acids,amidines and hydrazines have been first investigated with the B3 LYP/6-311++G** method.According to the potential energy profile,it can be predicted that the course of the reaction consists of five reactions containing six elementary reactions.The α-imino-3-pyridine formic acid and acetamidine form first an intermediate product through a dehydration reaction; the intermediate product further combines with hydrogen ion to form a positive ion; the positive ion reacts with anisole hydrazine by a dehydration reaction to form another positive ion; then,followed by two isomerization reactions,the final reaction with the acetate ion(Ac-) produces the final product.The research results reveal the laws of synthesis reaction of 1,3,5-substituted-1,2,4-triazoles by the carboxylic acids,amidines,hydrazines and their derivatives on theoretical level.It provides the systemic theoretical basis for the synthesis,development and application of 1,3,5-substituted-1,2,4-triazole compounds.