Rapidly solidified Al87Ni7Cu3Nd3 metallic glasses, prepared by using melt spinning, were treated under both isothermal and non-isothermal regime. The amorphous ribbon and the annealed samples were closely examined by ...Rapidly solidified Al87Ni7Cu3Nd3 metallic glasses, prepared by using melt spinning, were treated under both isothermal and non-isothermal regime. The amorphous ribbon and the annealed samples were closely examined by means of differential scanning calorimetric, conventional X-ray diffraction and high resolution transmission electron microscopy with selected-area electron diffraction, with special interest in primary crystallization into α-Al nanocrystalline particles, in order to understand structural characteristics of Al-based amorphous/nanocrystalline alloys, and nucleation and grain growth mechanism on the nanometer scale during primary crystallization. The results show that, the as-prepared ribbons are fully amorphous and homogeneous in the micron scale, but contain high density of quenched-in clusters or crystallite embryos. Primary crystallization mainly leads to formation of two-phase mixture of a-Al crystal and residual amorphous phase. The annealed ribbons exposed isother-mally at HOP C for 5, 130 minutes and heated continuously up to less than 310℃ at 40℃ C/min consist of large amount of α-Al fcc crystal nanoparticles dispersed uniformly in an amorphous matrix. However, a very little amount of finer orthorhombic Al3Ni intermetalics particles exist in the annealed ribbons heated up to 310℃. During primary crystallization, the leading kinetic mechanics to impede growth of the α-Al crystal is soft impingement, instead of geometric impingement.展开更多
With the rapid development of highway construction and formation of the highway network in China,the man- agement of pavement maintenance and rehabilitation （MR） activities has become important.In this paper,four di...With the rapid development of highway construction and formation of the highway network in China,the man- agement of pavement maintenance and rehabilitation （MR） activities has become important.In this paper,four discrete optimization models are proposed for different parties involved in the management system： government,highway agent,con- tractor and the common users.These four optimal decision models are formulated as linear integer programming problems with binary decision variables.The objective function and constraints are based on the pavement performance and prediction model using the pavement condition index （PCI）.Numerical experiments are carried out with the data from a highway system in Sichuan Province which show the feasibility and effectiveness of the proposed models.展开更多
The model of nuclear reactor dynamics is an initial-boundary value problems of a cou- pled nonlinear integrodifferential equation system of one ordinary differential equation and one par-- tial differential equation. ...The model of nuclear reactor dynamics is an initial-boundary value problems of a cou- pled nonlinear integrodifferential equation system of one ordinary differential equation and one par-- tial differential equation. In this this,paper,a linearized difference scheme is derived by the method of reduction of order.It is proved that the scheme is uniquely solvable and unconditionally convergent with the convergence rate of order two both in discrete H1norm and in discrete maxinum narm,and one needs only to solve a tridiagonal system of linear algebraic equations at each time lev- el.The method of reduction of order is an indirect constructing-difference-scheme method,which aim is for the analysis of solvablity and convergence of the constructed difference scheme.展开更多
[Objective] This study was conducted to develop some new iron yam （Dioscorea opposita） varieties with excellent cooking, eating and nutritional qualities. [Method] The fresh weight per plant, drying rate, dry weight...[Objective] This study was conducted to develop some new iron yam （Dioscorea opposita） varieties with excellent cooking, eating and nutritional qualities. [Method] The fresh weight per plant, drying rate, dry weight per plant, yield, allan- toin content, water soluble extract content and disease resistance of seven new iron yam cultivars （No.1, No.2, No.4, No.6, No.8, No.9 and No.10） obtained through spaceflight mutation breeding were measured and compared with control （No.11）. Then, the nutrition quality of two elite cultivars No. 6 and No.10 was determined by comparing with the control. [Result] The eight iron yam cultivars ranked in descend- ing order of their fresh weight per plant as follows： No.6（0.255 kg）〉No.10（0.254 kg）〉 No.4（0.242 kg）〉No.9（0.237 kg）〉No.1（0.233 kg）〉No.11（0.206 kg）〉No.2（0.191 kg）〉No.8 （0.157 kg）. There was no significant difference in fresh weight per plant between No.6 and No.10, but extremely significant difference between No.6 and the control, No.10 and the control. The eight iron yam cultivars ranked in descending order of their drying rate as follows： No.2 （32.641%）〉No.10 （32.230%）〉No.9 （28.223%）〉No.6 （25.174%）〉No.8（25.122%）〉No.11 （25.043%）〉No.1 （24.291%）〉No.4（20.234%）. The dry- ing rate of both No.6 and No.10 was higher than that of the control. The eight iron yam cultivars ranked in descending order of their dry weight per plant as follows： No.10（0.082 kg）〉No.9（0.067 kg）〉No.6（0.064 kg）〉No.2（0.062 kg）〉No.1（0.056 kg）〉No.11 （0.052 kg）〉No.4 （0.049 kg）〉No.8 （0.039 kg）. The dry weight per plant of both No.6 and No.10 is higher than that of the control. The eight iron yam cultivars ranked in descending order of their allantoin content as follows No.6 （0.484%）〉No.4 （0.467%）〉 No.10 （0.399%）〉No.ll （0.386%）〉No.9 （0.378%）〉No.8 （0.350%）〉No.2 （0.342）〉No.1 （0.325%）. The allantoin content of No.6 was significantly higher than that of No.10 and the control. There was significant difference in allantoin content between No.6 and No.10, but no significant difference between No 10 and the control. The eight iron yam cultivars ranked in descending order of their extract content as follows No. 6（20.49%）〉No.2（16.01%）〉No.4（15.54%） 〉No. 10（15.35%）〉No. 1 （14.48%）〉No. 11 （14.10%） 〉No.9（13.88%）〉No.8（11.87%）. The extract content of No.6 exhibited extremely sig- nificant difference with that of No.10 and the control, and the extract content of No. 10 was also significantly different from that of the control. The taste of No.10 was dry, soft, floury, sweet and fragrant, better than that of the other seven cultivars. No.6 had the strongest resistance to Gloeosporium pestis and Cylindrosporium dioscoreae. No.10 had a middle resistance to G. pestis and a strong resistance to C. dioscoreae. No.6 and No.10 had higher contents of starch, reducing sugar, pro- tein and ash, lower water content and better nutrition quality than the control. [Conclusion] No.10 can be popularized as a new variety of edible iron yam, and No.6 as a new variety of medicinal iron yam.展开更多
文摘Rapidly solidified Al87Ni7Cu3Nd3 metallic glasses, prepared by using melt spinning, were treated under both isothermal and non-isothermal regime. The amorphous ribbon and the annealed samples were closely examined by means of differential scanning calorimetric, conventional X-ray diffraction and high resolution transmission electron microscopy with selected-area electron diffraction, with special interest in primary crystallization into α-Al nanocrystalline particles, in order to understand structural characteristics of Al-based amorphous/nanocrystalline alloys, and nucleation and grain growth mechanism on the nanometer scale during primary crystallization. The results show that, the as-prepared ribbons are fully amorphous and homogeneous in the micron scale, but contain high density of quenched-in clusters or crystallite embryos. Primary crystallization mainly leads to formation of two-phase mixture of a-Al crystal and residual amorphous phase. The annealed ribbons exposed isother-mally at HOP C for 5, 130 minutes and heated continuously up to less than 310℃ at 40℃ C/min consist of large amount of α-Al fcc crystal nanoparticles dispersed uniformly in an amorphous matrix. However, a very little amount of finer orthorhombic Al3Ni intermetalics particles exist in the annealed ribbons heated up to 310℃. During primary crystallization, the leading kinetic mechanics to impede growth of the α-Al crystal is soft impingement, instead of geometric impingement.
基金Project supported by the National Natural Science Foundation of China (Grant No.70671064)
文摘With the rapid development of highway construction and formation of the highway network in China,the man- agement of pavement maintenance and rehabilitation （MR） activities has become important.In this paper,four discrete optimization models are proposed for different parties involved in the management system： government,highway agent,con- tractor and the common users.These four optimal decision models are formulated as linear integer programming problems with binary decision variables.The objective function and constraints are based on the pavement performance and prediction model using the pavement condition index （PCI）.Numerical experiments are carried out with the data from a highway system in Sichuan Province which show the feasibility and effectiveness of the proposed models.
基金NSF of Jiangsu Province (BK97004) and NSF of China (19801007)
文摘The model of nuclear reactor dynamics is an initial-boundary value problems of a cou- pled nonlinear integrodifferential equation system of one ordinary differential equation and one par-- tial differential equation. In this this,paper,a linearized difference scheme is derived by the method of reduction of order.It is proved that the scheme is uniquely solvable and unconditionally convergent with the convergence rate of order two both in discrete H1norm and in discrete maxinum narm,and one needs only to solve a tridiagonal system of linear algebraic equations at each time lev- el.The method of reduction of order is an indirect constructing-difference-scheme method,which aim is for the analysis of solvablity and convergence of the constructed difference scheme.
基金Supported by Special Fund for Public Health from State Administration of Traditional Chinese Medicine(Financial Institution[2011]76)Special Fund for Scientific Research of Traditional Chinese Medicine Industry(201207002)+1 种基金Henan Social Sciences Planning Project(2013BJJ084)Henan Industry-University-Research Institute Cooperation Project(142107000078)
文摘[Objective] This study was conducted to develop some new iron yam （Dioscorea opposita） varieties with excellent cooking, eating and nutritional qualities. [Method] The fresh weight per plant, drying rate, dry weight per plant, yield, allan- toin content, water soluble extract content and disease resistance of seven new iron yam cultivars （No.1, No.2, No.4, No.6, No.8, No.9 and No.10） obtained through spaceflight mutation breeding were measured and compared with control （No.11）. Then, the nutrition quality of two elite cultivars No. 6 and No.10 was determined by comparing with the control. [Result] The eight iron yam cultivars ranked in descend- ing order of their fresh weight per plant as follows： No.6（0.255 kg）〉No.10（0.254 kg）〉 No.4（0.242 kg）〉No.9（0.237 kg）〉No.1（0.233 kg）〉No.11（0.206 kg）〉No.2（0.191 kg）〉No.8 （0.157 kg）. There was no significant difference in fresh weight per plant between No.6 and No.10, but extremely significant difference between No.6 and the control, No.10 and the control. The eight iron yam cultivars ranked in descending order of their drying rate as follows： No.2 （32.641%）〉No.10 （32.230%）〉No.9 （28.223%）〉No.6 （25.174%）〉No.8（25.122%）〉No.11 （25.043%）〉No.1 （24.291%）〉No.4（20.234%）. The dry- ing rate of both No.6 and No.10 was higher than that of the control. The eight iron yam cultivars ranked in descending order of their dry weight per plant as follows： No.10（0.082 kg）〉No.9（0.067 kg）〉No.6（0.064 kg）〉No.2（0.062 kg）〉No.1（0.056 kg）〉No.11 （0.052 kg）〉No.4 （0.049 kg）〉No.8 （0.039 kg）. The dry weight per plant of both No.6 and No.10 is higher than that of the control. The eight iron yam cultivars ranked in descending order of their allantoin content as follows No.6 （0.484%）〉No.4 （0.467%）〉 No.10 （0.399%）〉No.ll （0.386%）〉No.9 （0.378%）〉No.8 （0.350%）〉No.2 （0.342）〉No.1 （0.325%）. The allantoin content of No.6 was significantly higher than that of No.10 and the control. There was significant difference in allantoin content between No.6 and No.10, but no significant difference between No 10 and the control. The eight iron yam cultivars ranked in descending order of their extract content as follows No. 6（20.49%）〉No.2（16.01%）〉No.4（15.54%） 〉No. 10（15.35%）〉No. 1 （14.48%）〉No. 11 （14.10%） 〉No.9（13.88%）〉No.8（11.87%）. The extract content of No.6 exhibited extremely sig- nificant difference with that of No.10 and the control, and the extract content of No. 10 was also significantly different from that of the control. The taste of No.10 was dry, soft, floury, sweet and fragrant, better than that of the other seven cultivars. No.6 had the strongest resistance to Gloeosporium pestis and Cylindrosporium dioscoreae. No.10 had a middle resistance to G. pestis and a strong resistance to C. dioscoreae. No.6 and No.10 had higher contents of starch, reducing sugar, pro- tein and ash, lower water content and better nutrition quality than the control. [Conclusion] No.10 can be popularized as a new variety of edible iron yam, and No.6 as a new variety of medicinal iron yam.
