A total of 28 yeast strains were obtained from the sea sediment of Antarctica.According to the results of routine identi-fication and molecular characterization,the strains belonged to species of Yarrowia lipolytica,D...A total of 28 yeast strains were obtained from the sea sediment of Antarctica.According to the results of routine identi-fication and molecular characterization,the strains belonged to species of Yarrowia lipolytica,Debaryomyces hansenii,Rhodotorula slooffiae,Rhodotorula mucilaginosa,Sporidiobolus salmonicolor,Aureobasidium pullulans,Mrakia frigida and Guehomyces pullu-lans,respectively.The Antarctica yeasts have wide potential applications in biotechnology,for some of them can produce b-galactosidase and killer toxins.展开更多
In this paper, we study the number of limit cycles appeared in Hopf bifurcations of a Lienard system with multiple parameters. As an application to some polynomial Lienard systems of the form x= y, y= -gin（x） - fn...In this paper, we study the number of limit cycles appeared in Hopf bifurcations of a Lienard system with multiple parameters. As an application to some polynomial Lienard systems of the form x= y, y= -gin（x） - fn（X）y, we obtain a new lower bound of maximal number of limit cycles which appear in Hopf bifurcation for arbitrary degrees m and n.展开更多
Developing novel electrode materials for li-thium-ion batteries （LIBs） with rapid charge/discharge cap- ability and high cycling stability remains a big challenge to date. Herein, we demonstrate the design and synth...Developing novel electrode materials for li-thium-ion batteries （LIBs） with rapid charge/discharge cap- ability and high cycling stability remains a big challenge to date. Herein, we demonstrate the design and synthesis of ul- trathin MoS2 nanosheets in-situ grown on sponge-like carbon nanospheres by a simple diffusion-controiled process. The unique sponge-like carbon nanosphere core can be used as ＂reservoir＂ of electrolyte by adsorbing to shorten the ion- diffusion path, and meanwhile as ＂elastomer＂ to alleviate the structural change of the MoS2 nanosheets during the charge/ discharge processes. Furthermore, the vertical ultrathin MoS2 nanosheets with broadened interlayer space greatly enrich the electrochemical active sites. Consequently, the as-obtained MoS2/C nanospheres exhibit increased specific capacities at various rates with superior cycling stability compared to the MoS2/C floccules. It is reckoned that the present concept can be extended to other electrode materials for achieving high- rate and stable LIBs.展开更多
This paper deals with the existence of Darboux first integrals for the planar polynomial differential systems x=x-y+P n+1(x,y)+xF2n(x,y),y=x+y+Q n+1(x,y)+yF2n(x,y),where P i(x,y),Q i(x,y)and F i(x,y)are homogeneous po...This paper deals with the existence of Darboux first integrals for the planar polynomial differential systems x=x-y+P n+1(x,y)+xF2n(x,y),y=x+y+Q n+1(x,y)+yF2n(x,y),where P i(x,y),Q i(x,y)and F i(x,y)are homogeneous polynomials of degree i.Within this class,we identify some new Darboux integrable systems having either a focus or a center at the origin.For such Darboux integrable systems having degrees 5and 9 we give the explicit expressions of their algebraic limit cycles.For the systems having degrees 3,5,7 and 9and restricted to a certain subclass we present necessary and sufficient conditions for being Darboux integrable.展开更多
基金supported by the Hi-Tech Researchand Development Program of China(863),the grant No. is 2006AA09Z403
文摘A total of 28 yeast strains were obtained from the sea sediment of Antarctica.According to the results of routine identi-fication and molecular characterization,the strains belonged to species of Yarrowia lipolytica,Debaryomyces hansenii,Rhodotorula slooffiae,Rhodotorula mucilaginosa,Sporidiobolus salmonicolor,Aureobasidium pullulans,Mrakia frigida and Guehomyces pullu-lans,respectively.The Antarctica yeasts have wide potential applications in biotechnology,for some of them can produce b-galactosidase and killer toxins.
基金supported by National Natural Science Foundation of China (Grant No.11271261)
文摘In this paper, we study the number of limit cycles appeared in Hopf bifurcations of a Lienard system with multiple parameters. As an application to some polynomial Lienard systems of the form x= y, y= -gin（x） - fn（X）y, we obtain a new lower bound of maximal number of limit cycles which appear in Hopf bifurcation for arbitrary degrees m and n.
基金supported by the National Natural Science Foundation of China(21522602,51672082 and 91534202)the Shanghai Rising-Star Program(15QA1401200)+2 种基金the Innovation Program of Shanghai Municipal Education Commissionthe Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningthe Fundamental Research Funds for the Central Universities(222201718002)
文摘Developing novel electrode materials for li-thium-ion batteries （LIBs） with rapid charge/discharge cap- ability and high cycling stability remains a big challenge to date. Herein, we demonstrate the design and synthesis of ul- trathin MoS2 nanosheets in-situ grown on sponge-like carbon nanospheres by a simple diffusion-controiled process. The unique sponge-like carbon nanosphere core can be used as ＂reservoir＂ of electrolyte by adsorbing to shorten the ion- diffusion path, and meanwhile as ＂elastomer＂ to alleviate the structural change of the MoS2 nanosheets during the charge/ discharge processes. Furthermore, the vertical ultrathin MoS2 nanosheets with broadened interlayer space greatly enrich the electrochemical active sites. Consequently, the as-obtained MoS2/C nanospheres exhibit increased specific capacities at various rates with superior cycling stability compared to the MoS2/C floccules. It is reckoned that the present concept can be extended to other electrode materials for achieving high- rate and stable LIBs.
基金supported by National Natural Science Foundation of China (Grant No. 11271252)Ministerio de Economiay Competitidad of Spain (Grant No. MTM2008-03437)+2 种基金 Agència de Gestió d’Ajuts Universitaris i de Recerca of Catalonia (Grant No. 2009SGR410)ICREA Academia,Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20110073110054)a Marie Curie International Research Staff Exchange Scheme Fellowship within the 7th European Community Framework Programme (Grant Nos. FP7-PEOPLE-2012-IRSES-316338 and 318999)
文摘This paper deals with the existence of Darboux first integrals for the planar polynomial differential systems x=x-y+P n+1(x,y)+xF2n(x,y),y=x+y+Q n+1(x,y)+yF2n(x,y),where P i(x,y),Q i(x,y)and F i(x,y)are homogeneous polynomials of degree i.Within this class,we identify some new Darboux integrable systems having either a focus or a center at the origin.For such Darboux integrable systems having degrees 5and 9 we give the explicit expressions of their algebraic limit cycles.For the systems having degrees 3,5,7 and 9and restricted to a certain subclass we present necessary and sufficient conditions for being Darboux integrable.
