The formation of periodic layered structure in Ni3Si/Zn diffusion couples with Zn in vapor or liquid state was investigated by SEM-EDS, FESEM and XRD. The results show that the diffusion path in solid-liquid reaction ...The formation of periodic layered structure in Ni3Si/Zn diffusion couples with Zn in vapor or liquid state was investigated by SEM-EDS, FESEM and XRD. The results show that the diffusion path in solid-liquid reaction is Ni3Si/（T＋γ）/γ/…T/γ/Ni4Zn12Si3/γ/…Ni4Zn12Si3/γ/Ni4Zn12Si3/δ…/Ni4Zn12Si3/δ/liquid-Zn, and the diffusion path in solid-vapor reaction is Ni3Si/θ/（T＋γ）/γ/…/T/γ/…T/γ/vapor-Zn. With increasing Zn diffusion flux, the diffusion reaction path moves toward the Zn-rich direction, and the distance from the Ni3Si substrate to the periodic layer pair nearest to the interface decreases. In the initial stage of both reactions,γphase nucleates and grows within T matrix phase at first, and then conjuncts together to form a band to reduce the surface energy. Based on the experimental results and diffusion kinetics analysis, the microstructure differences were compared and the formation mechanism of the periodic layered structure in Ni3Si/Zn system was discussed.展开更多
Evolution of periodic waves and solitary waves in Bose-Einstein condensates （BECs） with time-dependent atomic scattering length in an expulsive parabolic potential is studied. Based on the mapping deformation method...Evolution of periodic waves and solitary waves in Bose-Einstein condensates （BECs） with time-dependent atomic scattering length in an expulsive parabolic potential is studied. Based on the mapping deformation method, we successfully obtain periodic wave solutions and solitary wave solutions, including the bright and dark soliton solutions.The results in this paper include some in the literatures [Phys. Rev. Lett. 94 （2005） 050402 and Chin. Phys. Left. 22 （2005） 1855].展开更多
In this work we devise an algebraic method to uniformly construct rational form solitary wave solutions and Jacobi and Weierstrass doubly periodic wave solutions of physical interest for nonlinear evolution equations....In this work we devise an algebraic method to uniformly construct rational form solitary wave solutions and Jacobi and Weierstrass doubly periodic wave solutions of physical interest for nonlinear evolution equations. With the aid of symbolic computation, we apply the proposed method to solving the (1+1)-dimensional dispersive long wave equation and explicitly construct a series of exact solutions which include the rational form solitary wave solutions and elliptic doubly periodic wave solutions as special cases.展开更多
This paper summarizes the 'study On small hepatocellular carcinoma and its extensionII in Liver CancerInstitute, Zhongshan Hospital Of Shanghai MedicaI University during the past 25 years. The results 1ndl-cated t...This paper summarizes the 'study On small hepatocellular carcinoma and its extensionII in Liver CancerInstitute, Zhongshan Hospital Of Shanghai MedicaI University during the past 25 years. The results 1ndl-cated that it was an impOrtant approach to obtain long-term HCC survivOrs, of the 239 patients with 5-yearsurvival, small HCC resection accounted for 51. 4 %. It was an effective apprOach to lmprove the prognosisof HCC in the entire series, the 5-year survlval of lnpatients treated ln authorsI institution was 4. 8% in1958~1970, l2. 2 % in 197l ~ 1983, and 46. 7 % in l984~ 1995; which were correlated to the increaseProportion of small HCC resection in the series; it was more effective as compared to large HCC resection,the 5 year survival was 6l. 3 % (n= 645 ) versus 33. 6 % (n= 950). ExtensiOns of small HCC study includ-ed early detection and treatment of small recurrent HCC, Of the l47 patients wlth re-resection, the 5-yearsurvival was 48. 9% caIculated frOm the time Of first resectiOn. Another extenslon was conversiOn Of largeHCC intO small HCC, using multimodality combination treatment, 72 out of the 663 patients wlth surgical-ly verified unresectable HCCs have been converted to resectable, 5-year survival being 62' l %, wh1ch wascomparable tO that of small HCC resection. Studies on related basic aspect of small HCC such as cell originof recurrence, and mOlecular aspect of small HCC, indicated that biOlOgical characterlstics, particularly thetumor invasiveness, remalned the key link for further prolong survival after small HCC resection. Recent-ly, a'patient-like' human HCC metastatic medel in nude mice has been established. Experimental inter-ventions have also been tried. Clinical trials fOr preventiOn of recurrence after small HCC resection haveshown preliminary encouraging results. However, the IIcOst-effectivenessn Of screening, the invasiveness ofHCC, the multicentric origin, the coexisted Child C cirrhosis, etc., remained great chal1enge.展开更多
In this paper we consider averaging and finite difference methods for solving the 3-D boundary-value problem in a multilayered domain. We consider the metal concentration in the 3 layered peat blocks. Using experiment...In this paper we consider averaging and finite difference methods for solving the 3-D boundary-value problem in a multilayered domain. We consider the metal concentration in the 3 layered peat blocks. Using experimental data the mathematical model for calculating the concentration of metal at different points in peat layers is developed. A specific feature of these problems is that it is necessary to solve the 3-D boundary-value problems for the partial differential equations （PDEs） of the elliptic type of second order with piece-wise diffusion coefficients in the three layer domain. We develop here a finite-difference method for solving a problem of the above type with the periodical boundary condition in x direction. This procedure allows reducing the 3-D problem to a system of 2-D problems by using a circulant matrix.展开更多
We represent the exponential moment of the Brownian functionals under a nonlinear expectation according to the solution to a backward stochastic differential equation.As an application,we establish a large deviation p...We represent the exponential moment of the Brownian functionals under a nonlinear expectation according to the solution to a backward stochastic differential equation.As an application,we establish a large deviation principle of the Freidlin and Wentzell type under the corresponding nonlinear probability for diffusion processes with a small diffusion coefficient.展开更多
The GARCH diffusion model has received much attention in recent years, as it describes financial time series better when compared to many other models. In this paper, the authors study the empirical performance of Ame...The GARCH diffusion model has received much attention in recent years, as it describes financial time series better when compared to many other models. In this paper, the authors study the empirical performance of American option pricing model when the underlying asset follows the GARCH diffusion. The parameters of the GARCH diffusion model are estimated by the efficient importance sampling-based maximum likelihood （EIS-ML） method. Then the least-squares Monte Carlo （LSMC） method is introduced to price American options. Empirical pricing results on American put options in Hong Kong stock market shows that the GARCH diffusion model outperforms the classical constant volatility （CV） model significantly.展开更多
基金Projects(51271040,51171031)supported by the National Natural Science Foundation of ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions,China
文摘The formation of periodic layered structure in Ni3Si/Zn diffusion couples with Zn in vapor or liquid state was investigated by SEM-EDS, FESEM and XRD. The results show that the diffusion path in solid-liquid reaction is Ni3Si/（T＋γ）/γ/…T/γ/Ni4Zn12Si3/γ/…Ni4Zn12Si3/γ/Ni4Zn12Si3/δ…/Ni4Zn12Si3/δ/liquid-Zn, and the diffusion path in solid-vapor reaction is Ni3Si/θ/（T＋γ）/γ/…/T/γ/…T/γ/vapor-Zn. With increasing Zn diffusion flux, the diffusion reaction path moves toward the Zn-rich direction, and the distance from the Ni3Si substrate to the periodic layer pair nearest to the interface decreases. In the initial stage of both reactions,γphase nucleates and grows within T matrix phase at first, and then conjuncts together to form a band to reduce the surface energy. Based on the experimental results and diffusion kinetics analysis, the microstructure differences were compared and the formation mechanism of the periodic layered structure in Ni3Si/Zn system was discussed.
基金The project supported by Natioual Natural Science Foundation of China under Grant Nos. 1057508 and 10302018 and the Natural Science Foundation of Zhejiang Province of China under Grant No. Y605056The authors would like to thank Prof. Sen-Yue Lou for helpful discussions.
文摘Evolution of periodic waves and solitary waves in Bose-Einstein condensates （BECs） with time-dependent atomic scattering length in an expulsive parabolic potential is studied. Based on the mapping deformation method, we successfully obtain periodic wave solutions and solitary wave solutions, including the bright and dark soliton solutions.The results in this paper include some in the literatures [Phys. Rev. Lett. 94 （2005） 050402 and Chin. Phys. Left. 22 （2005） 1855].
文摘In this work we devise an algebraic method to uniformly construct rational form solitary wave solutions and Jacobi and Weierstrass doubly periodic wave solutions of physical interest for nonlinear evolution equations. With the aid of symbolic computation, we apply the proposed method to solving the (1+1)-dimensional dispersive long wave equation and explicitly construct a series of exact solutions which include the rational form solitary wave solutions and elliptic doubly periodic wave solutions as special cases.
文摘This paper summarizes the 'study On small hepatocellular carcinoma and its extensionII in Liver CancerInstitute, Zhongshan Hospital Of Shanghai MedicaI University during the past 25 years. The results 1ndl-cated that it was an impOrtant approach to obtain long-term HCC survivOrs, of the 239 patients with 5-yearsurvival, small HCC resection accounted for 51. 4 %. It was an effective apprOach to lmprove the prognosisof HCC in the entire series, the 5-year survlval of lnpatients treated ln authorsI institution was 4. 8% in1958~1970, l2. 2 % in 197l ~ 1983, and 46. 7 % in l984~ 1995; which were correlated to the increaseProportion of small HCC resection in the series; it was more effective as compared to large HCC resection,the 5 year survival was 6l. 3 % (n= 645 ) versus 33. 6 % (n= 950). ExtensiOns of small HCC study includ-ed early detection and treatment of small recurrent HCC, Of the l47 patients wlth re-resection, the 5-yearsurvival was 48. 9% caIculated frOm the time Of first resectiOn. Another extenslon was conversiOn Of largeHCC intO small HCC, using multimodality combination treatment, 72 out of the 663 patients wlth surgical-ly verified unresectable HCCs have been converted to resectable, 5-year survival being 62' l %, wh1ch wascomparable tO that of small HCC resection. Studies on related basic aspect of small HCC such as cell originof recurrence, and mOlecular aspect of small HCC, indicated that biOlOgical characterlstics, particularly thetumor invasiveness, remalned the key link for further prolong survival after small HCC resection. Recent-ly, a'patient-like' human HCC metastatic medel in nude mice has been established. Experimental inter-ventions have also been tried. Clinical trials fOr preventiOn of recurrence after small HCC resection haveshown preliminary encouraging results. However, the IIcOst-effectivenessn Of screening, the invasiveness ofHCC, the multicentric origin, the coexisted Child C cirrhosis, etc., remained great chal1enge.
文摘In this paper we consider averaging and finite difference methods for solving the 3-D boundary-value problem in a multilayered domain. We consider the metal concentration in the 3 layered peat blocks. Using experimental data the mathematical model for calculating the concentration of metal at different points in peat layers is developed. A specific feature of these problems is that it is necessary to solve the 3-D boundary-value problems for the partial differential equations （PDEs） of the elliptic type of second order with piece-wise diffusion coefficients in the three layer domain. We develop here a finite-difference method for solving a problem of the above type with the periodical boundary condition in x direction. This procedure allows reducing the 3-D problem to a system of 2-D problems by using a circulant matrix.
基金supported by National Natural Science Foundation of China (Grant No.10921101)WCU program of the Korea Science and Engineering Foundation (Grant No. R31-20007)National Science Foundation of US (Grant No. DMS-0906907)
文摘We represent the exponential moment of the Brownian functionals under a nonlinear expectation according to the solution to a backward stochastic differential equation.As an application,we establish a large deviation principle of the Freidlin and Wentzell type under the corresponding nonlinear probability for diffusion processes with a small diffusion coefficient.
基金supported by the National Natural Science Foundations of China under Grant No.71201013the National Science Fund for Distinguished Young Scholars of China under Grant No.70825006+1 种基金the Program for Changjiang Scholars and Innovative Research Team in University under Grant No.IRT0916the National Natural Science Innovation Research Group of China under Grant No.71221001
文摘The GARCH diffusion model has received much attention in recent years, as it describes financial time series better when compared to many other models. In this paper, the authors study the empirical performance of American option pricing model when the underlying asset follows the GARCH diffusion. The parameters of the GARCH diffusion model are estimated by the efficient importance sampling-based maximum likelihood （EIS-ML） method. Then the least-squares Monte Carlo （LSMC） method is introduced to price American options. Empirical pricing results on American put options in Hong Kong stock market shows that the GARCH diffusion model outperforms the classical constant volatility （CV） model significantly.
