The dephosphorization experiments of low phosphorus containing steel by CaO-based and BaO-based fluxes were carried out. The effects of the oxygen potential in molten steel and the BaO content in the slag on dephospho...The dephosphorization experiments of low phosphorus containing steel by CaO-based and BaO-based fluxes were carried out. The effects of the oxygen potential in molten steel and the BaO content in the slag on dephosphorization and rephosphorization of molten steel were analyzed. The results showed that the dephosphorization ratio of more than 50% and the ultra-low phosphorus content of less than 0.005% in steel were obtained by the three kinds of dephosphorization fluxes as the oxygen potential of molten steel higher than 400×10^-6. Rephosphorization of molten steel was serious as the oxygen content of molten steel lower than 10×10^-6. BaO-based fluxes can improve the dephosphorization effect and reduce the phosphorus pick-up effectively under the condition of weak deoxidization of molten steel （the oxygen potential is about 100×10^-6）, but can not prevent rephosphorization under the condition of deep deoxidization of molten steel （the oxygen potential less than 10×10^-6）.展开更多
This paper focus on solving the problem of seafloor control point absolute positioning with low vertical accuracy based on the survey ship sailing circle. The method of dealing with the systematic error based on a sem...This paper focus on solving the problem of seafloor control point absolute positioning with low vertical accuracy based on the survey ship sailing circle. The method of dealing with the systematic error based on a semi-parametric adjustment model was proposed. Firstly, the influence of sound velocity change on ranging error is analyzed. Secondly, a semi-parametric adjustment model for determining three-dimensional coordinates of seafloor control points was established. And respectively proposed solutions under two different conditions, the observation duration is an integral multiple or non-integer multiple of the long-period term of the ranging error. The simulation experiment shows that this method can obviously improve the accuracy of vertical solution of seafloor control point compared with the difference technique and the least-squares method when internal waves exist and observation duration is less than an integer multiple of the long-period term of the ranging error.展开更多
In contrast to conventional main-chain conjugated polymers, incorporation of electronically active conjugated oligomers into non-conjugated polymer backbones as pendant groups represents a promising alternative strate...In contrast to conventional main-chain conjugated polymers, incorporation of electronically active conjugated oligomers into non-conjugated polymer backbones as pendant groups represents a promising alternative strategy to developing novel electroactive polymer materials that are desirable for potential applications in organic electronics. This review focuses on polymers with thiophene in the side chain and summarizes the most important synthetic approaches to these polymers, including direct controlled polymerization techniques(e.g., ATRP, ROMP, and RAFT) as well as post-polymerization modifications. Additionally, various properties and applications of these polymers are discussed.展开更多
文摘The dephosphorization experiments of low phosphorus containing steel by CaO-based and BaO-based fluxes were carried out. The effects of the oxygen potential in molten steel and the BaO content in the slag on dephosphorization and rephosphorization of molten steel were analyzed. The results showed that the dephosphorization ratio of more than 50% and the ultra-low phosphorus content of less than 0.005% in steel were obtained by the three kinds of dephosphorization fluxes as the oxygen potential of molten steel higher than 400×10^-6. Rephosphorization of molten steel was serious as the oxygen content of molten steel lower than 10×10^-6. BaO-based fluxes can improve the dephosphorization effect and reduce the phosphorus pick-up effectively under the condition of weak deoxidization of molten steel （the oxygen potential is about 100×10^-6）, but can not prevent rephosphorization under the condition of deep deoxidization of molten steel （the oxygen potential less than 10×10^-6）.
基金The National Key Research and Development Program of China(No.2016YFB0501701)The National High-tech Research and Development Program of China(No.2013AA122501)+1 种基金National Natural Science Foundation of China(Nos.4187610341874016)。
文摘This paper focus on solving the problem of seafloor control point absolute positioning with low vertical accuracy based on the survey ship sailing circle. The method of dealing with the systematic error based on a semi-parametric adjustment model was proposed. Firstly, the influence of sound velocity change on ranging error is analyzed. Secondly, a semi-parametric adjustment model for determining three-dimensional coordinates of seafloor control points was established. And respectively proposed solutions under two different conditions, the observation duration is an integral multiple or non-integer multiple of the long-period term of the ranging error. The simulation experiment shows that this method can obviously improve the accuracy of vertical solution of seafloor control point compared with the difference technique and the least-squares method when internal waves exist and observation duration is less than an integer multiple of the long-period term of the ranging error.
基金supported by the Office of Naval Research(N000141110191)South Carolina National Aeronautics and Space Administration Experimental Program to Stimulate Competitive Research(22-NE-USC_Tang)
文摘In contrast to conventional main-chain conjugated polymers, incorporation of electronically active conjugated oligomers into non-conjugated polymer backbones as pendant groups represents a promising alternative strategy to developing novel electroactive polymer materials that are desirable for potential applications in organic electronics. This review focuses on polymers with thiophene in the side chain and summarizes the most important synthetic approaches to these polymers, including direct controlled polymerization techniques(e.g., ATRP, ROMP, and RAFT) as well as post-polymerization modifications. Additionally, various properties and applications of these polymers are discussed.
