Before his multi-stop visit to Mexico, Argentina, Peru, Colombia and Jamaica in Latin America and the Caribbean （LAC） early February 2018, then U.S. Secretary of State Rex Tillerson released many signals for Latin A...Before his multi-stop visit to Mexico, Argentina, Peru, Colombia and Jamaica in Latin America and the Caribbean （LAC） early February 2018, then U.S. Secretary of State Rex Tillerson released many signals for Latin America. Especially in his remarks at the University of Texas at Austin, he portrayed the presence of China and Russia in LAC as a ＂new imperial power＂ and called on nations of Latin America and the Caribbean to review and reassess China-LAC relations. By identifying China and Russia as critical reference variables for future U.S.- Latin America relations, he obviously went beyond the bilateral level of U.S.- Latin relations and implied the important changes in U.S. policy toward LAC that pressured by growing influence of extra-regional actors in LAC, the United States might strengthen its diplomatic efforts in LAC to maintain and consolidate its dominance in the region.展开更多
The massive vector bosons Z o, W ± and the scalar Higgs-boson H o assumed in weak interaction theory, but also the six quarks required in strong interactions are well understood in an alternative quantum field th...The massive vector bosons Z o, W ± and the scalar Higgs-boson H o assumed in weak interaction theory, but also the six quarks required in strong interactions are well understood in an alternative quantum field theory of fermions and bosons: Z o and W ± as well as all quark-antiquark states (here only the tt¯state is discussed) are described by bound states with scalar coupling between their massless constituents and have a structure similar to leptons. However, the scalar Higgs-boson H o corresponds to a state with vector coupling between the elementary constituents. Similar scalar states are expected also in the mass region of the mesons ω (0.782 GeV) - Υ ( 9.46 GeV). The underlying calculations can be run on line using the Web-address https://h2909473.stratoserver.net.展开更多
The precipitated silica matting agent was synthesized by chem-deposit method,sodium silicate and sulfurric acid as raw materials,appending dispersant and surfactant.The optimal parameters for the required precipitated...The precipitated silica matting agent was synthesized by chem-deposit method,sodium silicate and sulfurric acid as raw materials,appending dispersant and surfactant.The optimal parameters for the required precipitated silica with excellent properties are temperature 70～85℃,pH value 9,reaction liquid mass concentration 20%,the calcined temperature between 450～480℃.The result shows that the prepared precipitated silica pore volume is 1.0～1.3cm3/g,the partical size is smaller than 10um,D50 approximately 5um.The surface area is 320～430m2/g,the pore size is between 147～388.展开更多
文摘Before his multi-stop visit to Mexico, Argentina, Peru, Colombia and Jamaica in Latin America and the Caribbean （LAC） early February 2018, then U.S. Secretary of State Rex Tillerson released many signals for Latin America. Especially in his remarks at the University of Texas at Austin, he portrayed the presence of China and Russia in LAC as a ＂new imperial power＂ and called on nations of Latin America and the Caribbean to review and reassess China-LAC relations. By identifying China and Russia as critical reference variables for future U.S.- Latin America relations, he obviously went beyond the bilateral level of U.S.- Latin relations and implied the important changes in U.S. policy toward LAC that pressured by growing influence of extra-regional actors in LAC, the United States might strengthen its diplomatic efforts in LAC to maintain and consolidate its dominance in the region.
文摘The massive vector bosons Z o, W ± and the scalar Higgs-boson H o assumed in weak interaction theory, but also the six quarks required in strong interactions are well understood in an alternative quantum field theory of fermions and bosons: Z o and W ± as well as all quark-antiquark states (here only the tt¯state is discussed) are described by bound states with scalar coupling between their massless constituents and have a structure similar to leptons. However, the scalar Higgs-boson H o corresponds to a state with vector coupling between the elementary constituents. Similar scalar states are expected also in the mass region of the mesons ω (0.782 GeV) - Υ ( 9.46 GeV). The underlying calculations can be run on line using the Web-address https://h2909473.stratoserver.net.
文摘The precipitated silica matting agent was synthesized by chem-deposit method,sodium silicate and sulfurric acid as raw materials,appending dispersant and surfactant.The optimal parameters for the required precipitated silica with excellent properties are temperature 70～85℃,pH value 9,reaction liquid mass concentration 20%,the calcined temperature between 450～480℃.The result shows that the prepared precipitated silica pore volume is 1.0～1.3cm3/g,the partical size is smaller than 10um,D50 approximately 5um.The surface area is 320～430m2/g,the pore size is between 147～388.
