The microstructures and growth process characteristics precipitation-crystallization method were investigated by SEM, TEM of spherical Ni（OH）2 particles synthesized by the aqueous and XRD, and their growth mechanism...The microstructures and growth process characteristics precipitation-crystallization method were investigated by SEM, TEM of spherical Ni（OH）2 particles synthesized by the aqueous and XRD, and their growth mechanism was discussed. With the reaction beginning and continuing, amorphous Ni（OH）2 nano-crystallites grow up to spherical micron-particles with radially arranged crystallites. The nucleation, crystallization and re-crystallization led by Ostwald ripening simultaneously take place through the whole growth processes. With the course from reversible aggregation to irreversible agglomeration, the Ni（OH）2 particles tend to grow according to the template growth model： the growth on the crystallite templates stretching in the radius directions is free and quick, while the growth rate for crystallites in other directions is confined due to lower monomers concentration and tends to dissolve So it is only the radially arranged crystallites that predominate in the particle and lead to characteristic microstructures.展开更多
Germany＇s energy system is in transition towards less nuclear, lower carbon emissions and more renewables. Notwithstanding widespread neglect of its European dimension, this Energiewende will further exacerbate curre...Germany＇s energy system is in transition towards less nuclear, lower carbon emissions and more renewables. Notwithstanding widespread neglect of its European dimension, this Energiewende will further exacerbate current network fluctuations due to the significant increase in wind and solar power. Key data from Denmark show that this transition will soon bring the German national power system to its limits for absorbing the resulting intermittency, and increase the need for more cross-border power transfers. Yet network analysis of import/export data shows that Germany＇s position in the European power system is contrary to the Danish case. The need for a European solution for Germany＇s energy transition will therefore soon become evident. In order to establish the necessary infrastructure, the Energiewende needs hence to be guided by an economic approach designed to prevent further fractures in the Internal Electricity Market. Constructive negotiations with neighbouring countries on market designs and price signals will be important preconditions. The article emphasizes the still neglected European paradox of Germany＇s energy transition and presents working examples and possible solutions to uphold electricity supply in Europe＇s power house.展开更多
As is well known in cosmology, inflationary universe which shows rapid expansion of space is based on the phase transition of the vacuum exhibited by the Weinberg-Salam model of the electroweak interaction. The vacuum...As is well known in cosmology, inflationary universe which shows rapid expansion of space is based on the phase transition of the vacuum exhibited by the Weinberg-Salam model of the electroweak interaction. The vacuum has the property of a phase transition, just like water may become ice and vice versa. This shows that a vacuum possesses a substantial physical structure. The expansion rule of the universe is governed by the Friedmann equations and the Robertson-Walker metric. We explored another possibility of a space propulsion principle where the locally rapid expanding space generates the thrust, using the cosmology. In this paper, space propulsion principle is introduced from another angle （cosmology）, that is, the pressure of the field induced by local expansion of space is completely considered in the propulsion principle.展开更多
基金Project(50134020) supported by the National Natural Science Foundation of ChinaProject supported by Postdoctoral Fund of Central South University
文摘The microstructures and growth process characteristics precipitation-crystallization method were investigated by SEM, TEM of spherical Ni（OH）2 particles synthesized by the aqueous and XRD, and their growth mechanism was discussed. With the reaction beginning and continuing, amorphous Ni（OH）2 nano-crystallites grow up to spherical micron-particles with radially arranged crystallites. The nucleation, crystallization and re-crystallization led by Ostwald ripening simultaneously take place through the whole growth processes. With the course from reversible aggregation to irreversible agglomeration, the Ni（OH）2 particles tend to grow according to the template growth model： the growth on the crystallite templates stretching in the radius directions is free and quick, while the growth rate for crystallites in other directions is confined due to lower monomers concentration and tends to dissolve So it is only the radially arranged crystallites that predominate in the particle and lead to characteristic microstructures.
文摘Germany＇s energy system is in transition towards less nuclear, lower carbon emissions and more renewables. Notwithstanding widespread neglect of its European dimension, this Energiewende will further exacerbate current network fluctuations due to the significant increase in wind and solar power. Key data from Denmark show that this transition will soon bring the German national power system to its limits for absorbing the resulting intermittency, and increase the need for more cross-border power transfers. Yet network analysis of import/export data shows that Germany＇s position in the European power system is contrary to the Danish case. The need for a European solution for Germany＇s energy transition will therefore soon become evident. In order to establish the necessary infrastructure, the Energiewende needs hence to be guided by an economic approach designed to prevent further fractures in the Internal Electricity Market. Constructive negotiations with neighbouring countries on market designs and price signals will be important preconditions. The article emphasizes the still neglected European paradox of Germany＇s energy transition and presents working examples and possible solutions to uphold electricity supply in Europe＇s power house.
文摘As is well known in cosmology, inflationary universe which shows rapid expansion of space is based on the phase transition of the vacuum exhibited by the Weinberg-Salam model of the electroweak interaction. The vacuum has the property of a phase transition, just like water may become ice and vice versa. This shows that a vacuum possesses a substantial physical structure. The expansion rule of the universe is governed by the Friedmann equations and the Robertson-Walker metric. We explored another possibility of a space propulsion principle where the locally rapid expanding space generates the thrust, using the cosmology. In this paper, space propulsion principle is introduced from another angle （cosmology）, that is, the pressure of the field induced by local expansion of space is completely considered in the propulsion principle.
