Lie symmetry reduction of some truly ＂variable coefficient＂ wave equations which are singled out from a class of （1 ＋ 1）-dimensional variable coefficient nonlinear wave equations with respect to one and two-dimen...Lie symmetry reduction of some truly ＂variable coefficient＂ wave equations which are singled out from a class of （1 ＋ 1）-dimensional variable coefficient nonlinear wave equations with respect to one and two-dimensional algebras is carried out. Some classes of exact solutions of the investigated equations are found by means of both the reductions and some modern techniques such as additional equivalent transformations and hidden symmetries and so on. Conditional symmetries are also discussed.展开更多
Sir Arthur Conan Doyle wrote many mystery and detective stories from 1890s to 1910s, years saw the advancement of powerful modem science and technology, especially inventions of transportation means or machines that a...Sir Arthur Conan Doyle wrote many mystery and detective stories from 1890s to 1910s, years saw the advancement of powerful modem science and technology, especially inventions of transportation means or machines that accelerate mobility power in late-Victorian and Edwardian society. In some of these mystery or detective stories especially featuring the well-known sleuth Sherlock Holmes, Doyle tended to integrate an early subject＇s experience of shrunken space and reduced time into an unknown fear by delineating his characters who perceive horror and nervousness while facing or riding on a railway transportation, including mainly the steam railway in mysterious tales like ＂The Lost Special＂ and ＂The Man with the Watches＂ as well as in detective stories like ＂The Adventure of the Engineer＇s Thumb＂, ＂The Adventure of Bruce-Partington Plan＂, ＂Valley of Fear＂ and several others. How can this spatiotemporal mobility be connected to mysterious affairs which lead Doyle＇s quasi-detective characters and police power to spring into investigative action？ Railway, mobility, and horror are woven together into a driving force that facilitates our geographical and forensic exploration of Doyle＇s stories.展开更多
The greatest charm of science fiction is not the artistic imagination, but the scientific imagination.Liu Cixin＇s the Three-body Problem as a Chinese science fiction novel, reflected Chinese writer how to think scien...The greatest charm of science fiction is not the artistic imagination, but the scientific imagination.Liu Cixin＇s the Three-body Problem as a Chinese science fiction novel, reflected Chinese writer how to think science and technology and its possible future of mankind＇s imagination. This novel contained ＂Deconstruction＂ Utopia, ＂Transcendence＂ dystopia and ＂Composited＂ Heterotopias, Which fully demonstrated singularity politics＇s great ideological tension between post modernity thinking of in this or that and typical Chinese style doctrine and dialectics.展开更多
Built on artificial intelligence, digitalization, and information technologies, the ＂Third Industrial Revolution ＂＂ transforms large-scale assembly lines and flexible manufacturing system with fundamental modern ma...Built on artificial intelligence, digitalization, and information technologies, the ＂Third Industrial Revolution ＂＂ transforms large-scale assembly lines and flexible manufacturing system with fundamental modern manufacturing technologies and features personalized manufacturing, which is enabled by reconfigurable manufacturing system, and quick market response. It is a profound transformation of techno-economic paradigms, imbedded in the technology, management, and institutional systems. As this revolution deepens, it is likely that manufacturing and the manufacturing sector would acquire new definitions. In addition, the resource foundation and factor structure, which are central to the competitiveness of a nation and an enterprise, would perhaps be reconfigured, hence rewriting the landscape of global industrial competition. Under this scenario, the ＂smiling curve ＇＂ which used to portray the economic features of the value chain, may change into a ＂silence curve＂ or even ＂sadness curve ＂. The catching- up pathway of latecomer countries, as predicted by the traditional ＇flying geese model＂, is likely to be blocked, solidifying the division of＂core and periphery countries＂ which is unfavorable to developing countries. Industrial competition between countries would move from competition between enterprises and supply chains to competition in industrial ecosystems, matdng system adaptability and dynamics the key to long-term industrial competitiveness. As an effort to embrace the ＂Third Industrial Revolution＂ and meet the challenges brought by ＂multi-facets competition＂ with developed industrial nations in various links of value chain, in the future China should make appropriate adjustments in its strategies for economic transition and upgrading, global competition, technological innovation, industrial development and information technology.展开更多
The research on the architecture and urbanism of the former Portuguese Africa allows us to consider and to establish the real intrinsic value, typological and morphological diversity, and the lengthy duration of the l...The research on the architecture and urbanism of the former Portuguese Africa allows us to consider and to establish the real intrinsic value, typological and morphological diversity, and the lengthy duration of the legacy of this architectural/urban heritage. Portuguese colonization in Africa produced more recently, mostly in the period 1950-1975, some vast and great material values, of which seven or eight main cities, including the vast contents of their modern architecture, are striking examples. We can evaluate the most positive aspects with future impact represented by this Portuguese architects＇ practice （cultural ethics, use of modern technology, and service to society） and the architectonic work produced during that era. Although these cities and its architecture were created within a late colonial context of indisputable discrimination, they have prevailed despite wars and circumstantial abandonment. Now they represent a consistent material basis for the modernization and/or revitalization of urban life in these countries. Architects that are at present working and intervening in these countries should understand this ambivalence and complementary nature between the ex-colonial ＂concrete city＂ and the ＂informal city＂ pre- and post-colonial, so that their performance is socially and culturally informed, correct, and positive.展开更多
Rapid developments in both fundamental science and modern technology that target water-related problems, including the physical nature of our planet and environment, the origin of life, energy production via water spl...Rapid developments in both fundamental science and modern technology that target water-related problems, including the physical nature of our planet and environment, the origin of life, energy production via water splitting, and water purification, all call for a molecular-level understanding of water. This invokes relentless efforts to further our understanding of the basic science of water. Current challenges to achieve a molecular picture of the peculiar properties and behavior of water are discussed herein, with a particular focus on the structure and dynamics of bulk and surface water, the molecular mechanisms of water wetting and splitting, application-oriented research on water decontamination and desalination, and the development of complementary techniques for probing water at the nanoscale.展开更多
Co0.6Cu0.16Ni0.24Fe2O4/multi-walled carbon nanotube nanocomposites (CCNF/MWCNTs) were synthesized by solution filling method.The phase structure,thermal stability,morphology and electrical-magnetic properties of the s...Co0.6Cu0.16Ni0.24Fe2O4/multi-walled carbon nanotube nanocomposites (CCNF/MWCNTs) were synthesized by solution filling method.The phase structure,thermal stability,morphology and electrical-magnetic properties of the samples were characterized by means of modern testing technology.The effect of iron concentration,filling time,sintering temperature on their electrical and magnetic performance was discussed.The results indicated that conductivity was related to the content of MWCNTs,while the magnetism correlated with the volume fraction of the filled CCNF in the composites.When the optimal condition satisfied the filling time of 18 h,ferric concentration of 0.25 mol L-1 and sintering temperature of 350°C,the prepared composite had the best magnetic loss performance,and its minimum reflection loss reached-22.47 dB on 9.76 GHz,the available bandwidth was beyond 2.0 GHz.Hence,the obtained composite can be used as advancing absorption and shielding material due to its favorable microwave absorbing property.展开更多
基金Supported by the National Key Basic Research Project of China under Grant No.2010CB126600the National Natural Science Foundation of China under Grant No.60873070+2 种基金Shanghai Leading Academic Discipline Project No.B114the Postdoctoral Science Foundation of China under Grant No.20090450067Shanghai Postdoctoral Science Foundation under Grant No.09R21410600
文摘Lie symmetry reduction of some truly ＂variable coefficient＂ wave equations which are singled out from a class of （1 ＋ 1）-dimensional variable coefficient nonlinear wave equations with respect to one and two-dimensional algebras is carried out. Some classes of exact solutions of the investigated equations are found by means of both the reductions and some modern techniques such as additional equivalent transformations and hidden symmetries and so on. Conditional symmetries are also discussed.
文摘Sir Arthur Conan Doyle wrote many mystery and detective stories from 1890s to 1910s, years saw the advancement of powerful modem science and technology, especially inventions of transportation means or machines that accelerate mobility power in late-Victorian and Edwardian society. In some of these mystery or detective stories especially featuring the well-known sleuth Sherlock Holmes, Doyle tended to integrate an early subject＇s experience of shrunken space and reduced time into an unknown fear by delineating his characters who perceive horror and nervousness while facing or riding on a railway transportation, including mainly the steam railway in mysterious tales like ＂The Lost Special＂ and ＂The Man with the Watches＂ as well as in detective stories like ＂The Adventure of the Engineer＇s Thumb＂, ＂The Adventure of Bruce-Partington Plan＂, ＂Valley of Fear＂ and several others. How can this spatiotemporal mobility be connected to mysterious affairs which lead Doyle＇s quasi-detective characters and police power to spring into investigative action？ Railway, mobility, and horror are woven together into a driving force that facilitates our geographical and forensic exploration of Doyle＇s stories.
文摘The greatest charm of science fiction is not the artistic imagination, but the scientific imagination.Liu Cixin＇s the Three-body Problem as a Chinese science fiction novel, reflected Chinese writer how to think science and technology and its possible future of mankind＇s imagination. This novel contained ＂Deconstruction＂ Utopia, ＂Transcendence＂ dystopia and ＂Composited＂ Heterotopias, Which fully demonstrated singularity politics＇s great ideological tension between post modernity thinking of in this or that and typical Chinese style doctrine and dialectics.
文摘Built on artificial intelligence, digitalization, and information technologies, the ＂Third Industrial Revolution ＂＂ transforms large-scale assembly lines and flexible manufacturing system with fundamental modern manufacturing technologies and features personalized manufacturing, which is enabled by reconfigurable manufacturing system, and quick market response. It is a profound transformation of techno-economic paradigms, imbedded in the technology, management, and institutional systems. As this revolution deepens, it is likely that manufacturing and the manufacturing sector would acquire new definitions. In addition, the resource foundation and factor structure, which are central to the competitiveness of a nation and an enterprise, would perhaps be reconfigured, hence rewriting the landscape of global industrial competition. Under this scenario, the ＂smiling curve ＇＂ which used to portray the economic features of the value chain, may change into a ＂silence curve＂ or even ＂sadness curve ＂. The catching- up pathway of latecomer countries, as predicted by the traditional ＇flying geese model＂, is likely to be blocked, solidifying the division of＂core and periphery countries＂ which is unfavorable to developing countries. Industrial competition between countries would move from competition between enterprises and supply chains to competition in industrial ecosystems, matdng system adaptability and dynamics the key to long-term industrial competitiveness. As an effort to embrace the ＂Third Industrial Revolution＂ and meet the challenges brought by ＂multi-facets competition＂ with developed industrial nations in various links of value chain, in the future China should make appropriate adjustments in its strategies for economic transition and upgrading, global competition, technological innovation, industrial development and information technology.
文摘The research on the architecture and urbanism of the former Portuguese Africa allows us to consider and to establish the real intrinsic value, typological and morphological diversity, and the lengthy duration of the legacy of this architectural/urban heritage. Portuguese colonization in Africa produced more recently, mostly in the period 1950-1975, some vast and great material values, of which seven or eight main cities, including the vast contents of their modern architecture, are striking examples. We can evaluate the most positive aspects with future impact represented by this Portuguese architects＇ practice （cultural ethics, use of modern technology, and service to society） and the architectonic work produced during that era. Although these cities and its architecture were created within a late colonial context of indisputable discrimination, they have prevailed despite wars and circumstantial abandonment. Now they represent a consistent material basis for the modernization and/or revitalization of urban life in these countries. Architects that are at present working and intervening in these countries should understand this ambivalence and complementary nature between the ex-colonial ＂concrete city＂ and the ＂informal city＂ pre- and post-colonial, so that their performance is socially and culturally informed, correct, and positive.
基金We thank discussion and help from Chongqin Zhu and Dr. Hui Li, Dr. Z. X. Cao, and Dr. Y. Luo during manuscript preparation. Financial support from NIST, the National Basic Research Program of China （No. 2012CB921403） and the National Natural Science Foundationof China （Nos. 11474328, 11290164, and 11222431） and CAS are gratefully acknowledged.
文摘Rapid developments in both fundamental science and modern technology that target water-related problems, including the physical nature of our planet and environment, the origin of life, energy production via water splitting, and water purification, all call for a molecular-level understanding of water. This invokes relentless efforts to further our understanding of the basic science of water. Current challenges to achieve a molecular picture of the peculiar properties and behavior of water are discussed herein, with a particular focus on the structure and dynamics of bulk and surface water, the molecular mechanisms of water wetting and splitting, application-oriented research on water decontamination and desalination, and the development of complementary techniques for probing water at the nanoscale.
基金supported by the National Natural Science Foundation of China (Grant No. 21071125)the Science and Technology Key Project of Zhejiang Province (Grant No. 2010C11053)the subproject of Science-Technology Innovation Team in Zhejiang Province (Grant No.2011R09006-06)
文摘Co0.6Cu0.16Ni0.24Fe2O4/multi-walled carbon nanotube nanocomposites (CCNF/MWCNTs) were synthesized by solution filling method.The phase structure,thermal stability,morphology and electrical-magnetic properties of the samples were characterized by means of modern testing technology.The effect of iron concentration,filling time,sintering temperature on their electrical and magnetic performance was discussed.The results indicated that conductivity was related to the content of MWCNTs,while the magnetism correlated with the volume fraction of the filled CCNF in the composites.When the optimal condition satisfied the filling time of 18 h,ferric concentration of 0.25 mol L-1 and sintering temperature of 350°C,the prepared composite had the best magnetic loss performance,and its minimum reflection loss reached-22.47 dB on 9.76 GHz,the available bandwidth was beyond 2.0 GHz.Hence,the obtained composite can be used as advancing absorption and shielding material due to its favorable microwave absorbing property.
