The kinetics of free radical decay in the polymerization of MMA initiated by AIBN was studied by means of ESR spectroscopy. It was found that the curves of radical decay are strongly associated with the reaction tempe...The kinetics of free radical decay in the polymerization of MMA initiated by AIBN was studied by means of ESR spectroscopy. It was found that the curves of radical decay are strongly associated with the reaction temperature, the initiator concentration and the solvent. In the case of the radical polymerization carried out at high temperature or in solution, the radical concentration first reached a maximum, then declined monotonously with reaction time. It was also found that the greater the amount of initiator or the higher the temperature, the more rapidly the radicals decay. When the bulk polymerization was implemented at a relatively low temperature, the curves of radical decay became more complicated, i.e., the radical concentration rapidly rose to a maximum, then dropped to a minimum, finally increased again with reaction time. Taking into account the diffusion effect, a semi-empirical equation is suggested to describe the kinetics of propagating radical decay.展开更多
The heat transfer phenomena and driving forces of slag bath flow in ESR process were analyzed, and the mathematical models in ESR system were reviewed and evaluated. The electromagnetic force is the main driving force...The heat transfer phenomena and driving forces of slag bath flow in ESR process were analyzed, and the mathematical models in ESR system were reviewed and evaluated. The electromagnetic force is the main driving force for the flow formation in the ESR slag pool, and the temperature difference in the pool creates a convective flow in the system. The shape of the electrode tip has an effect on electromagnetic field distribution in slag pool, thus affects the flow pattern. Finally an improved mathematical model of slag pool flow was proposed.展开更多
针对Buck变换器传统输出纹波电压分析不够精确的问题,提出了考虑电容等效串联电阻(Equivalent Series Resistance,ESR)的纹波电压建模方法,较之传统的纹波电压分析方法,文中提出的建模方法不仅能反映其非线性本质特征,而且该建模结果具...针对Buck变换器传统输出纹波电压分析不够精确的问题,提出了考虑电容等效串联电阻(Equivalent Series Resistance,ESR)的纹波电压建模方法,较之传统的纹波电压分析方法,文中提出的建模方法不仅能反映其非线性本质特征,而且该建模结果具有较高的精度。仿真和实验结果验证了理论分析的正确性,研究结果可为高精度Buck变换器分析和设计提供理论依据。展开更多
The oxidation of alloying elements during the ESR of stainless steel has been studied. The model previously developed by WEI and Mitchell for the chemical reactions and mass transfer processes during ESR was applied t...The oxidation of alloying elements during the ESR of stainless steel has been studied. The model previously developed by WEI and Mitchell for the chemical reactions and mass transfer processes during ESR was applied to the remelting of the high Cr steel 1Cr18Ni9(Ti).The laboratory data for the unsteady state A.C.ESR were analyzed and dealt with by the model.When the remelting process reached a steady state,an oxidant(Fe_2O_3 powder)or a deoxidant(Ca-Si powder or metallic Ca)was added to the slag bath.The results showed that this model is applicable to the remelting of stainless steel rather precisely, and it is expected that the model may offer a reliable basis for the control of composition during practical ESR of high alloy steel. Also,the oxidation of Cr in the steel must be noticed when its content is high;but it is entirely possible to adjust the Cr content of ingot within a considerable range,using a special technique by means of the slag-metal reactions during the remelting.展开更多
Breast cancer is the leading cause of death in women. Prognosis of breast cancer is often pessimistic because the tumors are prone to metastasizing to the bone, brain, and lung. The estrogen signaling receptor (ESR) p...Breast cancer is the leading cause of death in women. Prognosis of breast cancer is often pessimistic because the tumors are prone to metastasizing to the bone, brain, and lung. The estrogen signaling receptor (ESR) pathway contains 39 main genes and proteins which makes it one of the larger signaling pathways. Predominately this pathway and the proteins within are involved in breast growth and development, making it a prospective area of study for breast cancer. While the healthy ESR pathway has been constructed and is well established, a mechanistic model of mutated genes of ESR pathway has not been delved upon. Such mutated models could be utilized for selecting combinational targets for drug therapies, as well as elucidating crosstalk between other pathways and feedback mechanisms. To construct the mutated models of the ESR pathway it is imperative to assess what is currently understood in the literature and what inconsistencies exist in order to resolve them. Without this information, a model of the ESR pathway will be unreliable and likely unproductive. This review is the detailed literature survey of the biological studies performed on ESR pathways genes, and their respective roles in breast cancer. Furthermore, the details mentioned in the review can be beneficial for the integrated study of the ESR pathway genes, which includes, structural and dynamics study of the genes products, to have a holistic understanding of the cancer mechanism.展开更多
文摘The kinetics of free radical decay in the polymerization of MMA initiated by AIBN was studied by means of ESR spectroscopy. It was found that the curves of radical decay are strongly associated with the reaction temperature, the initiator concentration and the solvent. In the case of the radical polymerization carried out at high temperature or in solution, the radical concentration first reached a maximum, then declined monotonously with reaction time. It was also found that the greater the amount of initiator or the higher the temperature, the more rapidly the radicals decay. When the bulk polymerization was implemented at a relatively low temperature, the curves of radical decay became more complicated, i.e., the radical concentration rapidly rose to a maximum, then dropped to a minimum, finally increased again with reaction time. Taking into account the diffusion effect, a semi-empirical equation is suggested to describe the kinetics of propagating radical decay.
基金Project Sponsored by National Nature Science Foundation(59674031)
文摘The heat transfer phenomena and driving forces of slag bath flow in ESR process were analyzed, and the mathematical models in ESR system were reviewed and evaluated. The electromagnetic force is the main driving force for the flow formation in the ESR slag pool, and the temperature difference in the pool creates a convective flow in the system. The shape of the electrode tip has an effect on electromagnetic field distribution in slag pool, thus affects the flow pattern. Finally an improved mathematical model of slag pool flow was proposed.
文摘针对Buck变换器传统输出纹波电压分析不够精确的问题,提出了考虑电容等效串联电阻(Equivalent Series Resistance,ESR)的纹波电压建模方法,较之传统的纹波电压分析方法,文中提出的建模方法不仅能反映其非线性本质特征,而且该建模结果具有较高的精度。仿真和实验结果验证了理论分析的正确性,研究结果可为高精度Buck变换器分析和设计提供理论依据。
文摘The oxidation of alloying elements during the ESR of stainless steel has been studied. The model previously developed by WEI and Mitchell for the chemical reactions and mass transfer processes during ESR was applied to the remelting of the high Cr steel 1Cr18Ni9(Ti).The laboratory data for the unsteady state A.C.ESR were analyzed and dealt with by the model.When the remelting process reached a steady state,an oxidant(Fe_2O_3 powder)or a deoxidant(Ca-Si powder or metallic Ca)was added to the slag bath.The results showed that this model is applicable to the remelting of stainless steel rather precisely, and it is expected that the model may offer a reliable basis for the control of composition during practical ESR of high alloy steel. Also,the oxidation of Cr in the steel must be noticed when its content is high;but it is entirely possible to adjust the Cr content of ingot within a considerable range,using a special technique by means of the slag-metal reactions during the remelting.
文摘Breast cancer is the leading cause of death in women. Prognosis of breast cancer is often pessimistic because the tumors are prone to metastasizing to the bone, brain, and lung. The estrogen signaling receptor (ESR) pathway contains 39 main genes and proteins which makes it one of the larger signaling pathways. Predominately this pathway and the proteins within are involved in breast growth and development, making it a prospective area of study for breast cancer. While the healthy ESR pathway has been constructed and is well established, a mechanistic model of mutated genes of ESR pathway has not been delved upon. Such mutated models could be utilized for selecting combinational targets for drug therapies, as well as elucidating crosstalk between other pathways and feedback mechanisms. To construct the mutated models of the ESR pathway it is imperative to assess what is currently understood in the literature and what inconsistencies exist in order to resolve them. Without this information, a model of the ESR pathway will be unreliable and likely unproductive. This review is the detailed literature survey of the biological studies performed on ESR pathways genes, and their respective roles in breast cancer. Furthermore, the details mentioned in the review can be beneficial for the integrated study of the ESR pathway genes, which includes, structural and dynamics study of the genes products, to have a holistic understanding of the cancer mechanism.
