Empirical studies have shown that a large number of financial asset returns exhibit fat tails （leptokurtosis） and are often characterized by volatility clustering and asymmetry. This paper considers the ability of t...Empirical studies have shown that a large number of financial asset returns exhibit fat tails （leptokurtosis） and are often characterized by volatility clustering and asymmetry. This paper considers the ability of the GARCH-Type （Generalized Autoregressive Conditional Heteroskedasticity） models to capture the stylized features of volatility in national stock market returns for three countries （Portugal, Spain and Greece）. The results of this paper suggest that in the presence of asymmetric responses to innovations in the market, the ARMA （1,1）-GJRGARCH（1,1） skewed Student-t model which accommodates both the skewness and the kurtosis of financial time series is preferred.展开更多
This study aims to find the effect of financial risks, price risks and market risks on the Earning Response Coefficients （ERC） for China Commercial Banks. The research methodologies use the traditional cumulative ab...This study aims to find the effect of financial risks, price risks and market risks on the Earning Response Coefficients （ERC） for China Commercial Banks. The research methodologies use the traditional cumulative abnormal returns and the unexpected earning as the main dependent and independent variables. The evidences show that： （1） There is a strong returns-to-earnings relation for banks; （2） The liquidity risk has information content beyond earnings changes in the returns-to-earnings relation. This probably due to the reason that managers of banks find the level of liquidity that fulfilled the need of investors and at the same time earns good profits for the banks.展开更多
For the future energy system, we propose a new closed nuclear energy cycle system, which consists of an accelerator-driven external neutron source, a ceramic reactor and an extend AIROX reprocessing. The attractive fe...For the future energy system, we propose a new closed nuclear energy cycle system, which consists of an accelerator-driven external neutron source, a ceramic reactor and an extend AIROX reprocessing. The attractive features of this system are as follows. （l） The operating mode of the reactor is a combination of subcritical mode and critical mode. initially, the reactor would be driven by the accelerator external neutron source in subcritical mode. A few years later, the reactor would reach the critical mode, and then would operate for a long time. （2） Nuclear fuels, coolants, and structure materials in the ceramic reactor core are made up of ceramic with excellent thermodynamics properties and neutron performance. Therefore, the ceramic reactor has extremely inherent safety, good breeding performance and high power generation efficiency. （3） Fuel reprocessing uses an extend AIROX reprocessing, which is a simple high-temperature dry process and rarely involved in chemical process. In this reprocessing, only most of fission products are separated. Other isotopes, including uranium isotopes, transuranic nuclides and long-lived fission products, would re-enter the reactor as new fuels. Therefore, this closed nuclear energy system could be known as ADANES, short for Accelerator-Driven Advanced Nuclear Energy System, which can greatly improve the utilization rate of nuclear fuels, enhance the nuclear safety, reduce the nuclear proliferation and become a sustainable and low-carbon energy supply for thousands of years.展开更多
The aminolysis can effectively introduce primary amine （- quent surface fiiofunctionalization reactions. However, less NH2） groups onto polyester materials, enabling a variety of subse- attention has been paid to th...The aminolysis can effectively introduce primary amine （- quent surface fiiofunctionalization reactions. However, less NH2） groups onto polyester materials, enabling a variety of subse- attention has been paid to the basic knowledge of aminolysis reac- tion in terms of reaction kinetics and its influences on materials properties. In this study, taking the widely used poly（e-caprolactone） （PCL） as a typical example, the influences of diamines and solvent property on the surface -NH2 density are firstly assessed by using X-ray photoelectron spectroscopy （XPS） and colorimetric analysis. Results show that smaller dia- mine molecules and nonpolar alcohols could accelerate the reaction. The reaction kinetics with 1,6-hexanediamine is further investigated as a function of temperature, reaction time, and diamine concentration. During the initial stage, the reaction shows a 1^st order kinetics with the diamine concentration and has an activation energy of 54.5 kJ/mol. Ionization state of the -NH2 groups on the PCL surface is determined, revealing that the pKa of -NH3^＋ （〈5） is much lower than that of the corresponding diamine molecules in solution. After aminolysis, surface hydrophilicity of PCL membrane is significantly enhanced, while surface elastic modulus and average molecular weight are decreased to some extent, and others such as weight, surface mor- phology and bulk mechanical strength are not apparently changed. The introduced -NH2 groups are found to be largely lost at 37 ℃, but can be mostly maintained at low temperature.展开更多
文摘Empirical studies have shown that a large number of financial asset returns exhibit fat tails （leptokurtosis） and are often characterized by volatility clustering and asymmetry. This paper considers the ability of the GARCH-Type （Generalized Autoregressive Conditional Heteroskedasticity） models to capture the stylized features of volatility in national stock market returns for three countries （Portugal, Spain and Greece）. The results of this paper suggest that in the presence of asymmetric responses to innovations in the market, the ARMA （1,1）-GJRGARCH（1,1） skewed Student-t model which accommodates both the skewness and the kurtosis of financial time series is preferred.
文摘This study aims to find the effect of financial risks, price risks and market risks on the Earning Response Coefficients （ERC） for China Commercial Banks. The research methodologies use the traditional cumulative abnormal returns and the unexpected earning as the main dependent and independent variables. The evidences show that： （1） There is a strong returns-to-earnings relation for banks; （2） The liquidity risk has information content beyond earnings changes in the returns-to-earnings relation. This probably due to the reason that managers of banks find the level of liquidity that fulfilled the need of investors and at the same time earns good profits for the banks.
基金supported by the"Strategic Priority Research Program"of the Chinese Academy of Sciences(Grant No.XDA03030100)the National Natural Science Foundation of China(Grant No.11605264)
文摘For the future energy system, we propose a new closed nuclear energy cycle system, which consists of an accelerator-driven external neutron source, a ceramic reactor and an extend AIROX reprocessing. The attractive features of this system are as follows. （l） The operating mode of the reactor is a combination of subcritical mode and critical mode. initially, the reactor would be driven by the accelerator external neutron source in subcritical mode. A few years later, the reactor would reach the critical mode, and then would operate for a long time. （2） Nuclear fuels, coolants, and structure materials in the ceramic reactor core are made up of ceramic with excellent thermodynamics properties and neutron performance. Therefore, the ceramic reactor has extremely inherent safety, good breeding performance and high power generation efficiency. （3） Fuel reprocessing uses an extend AIROX reprocessing, which is a simple high-temperature dry process and rarely involved in chemical process. In this reprocessing, only most of fission products are separated. Other isotopes, including uranium isotopes, transuranic nuclides and long-lived fission products, would re-enter the reactor as new fuels. Therefore, this closed nuclear energy system could be known as ADANES, short for Accelerator-Driven Advanced Nuclear Energy System, which can greatly improve the utilization rate of nuclear fuels, enhance the nuclear safety, reduce the nuclear proliferation and become a sustainable and low-carbon energy supply for thousands of years.
基金financially supported by the National Natural Science Foundation of China (20934003)the National Basic Research Program of China (2011CB606203)
文摘The aminolysis can effectively introduce primary amine （- quent surface fiiofunctionalization reactions. However, less NH2） groups onto polyester materials, enabling a variety of subse- attention has been paid to the basic knowledge of aminolysis reac- tion in terms of reaction kinetics and its influences on materials properties. In this study, taking the widely used poly（e-caprolactone） （PCL） as a typical example, the influences of diamines and solvent property on the surface -NH2 density are firstly assessed by using X-ray photoelectron spectroscopy （XPS） and colorimetric analysis. Results show that smaller dia- mine molecules and nonpolar alcohols could accelerate the reaction. The reaction kinetics with 1,6-hexanediamine is further investigated as a function of temperature, reaction time, and diamine concentration. During the initial stage, the reaction shows a 1^st order kinetics with the diamine concentration and has an activation energy of 54.5 kJ/mol. Ionization state of the -NH2 groups on the PCL surface is determined, revealing that the pKa of -NH3^＋ （〈5） is much lower than that of the corresponding diamine molecules in solution. After aminolysis, surface hydrophilicity of PCL membrane is significantly enhanced, while surface elastic modulus and average molecular weight are decreased to some extent, and others such as weight, surface mor- phology and bulk mechanical strength are not apparently changed. The introduced -NH2 groups are found to be largely lost at 37 ℃, but can be mostly maintained at low temperature.
