High-strength pipeline steel and large diameter line pipes are often used to increase the capacity of transportation and reduce the cost associated with the construction and operation of long-distance gas pipeline pro...High-strength pipeline steel and large diameter line pipes are often used to increase the capacity of transportation and reduce the cost associated with the construction and operation of long-distance gas pipeline projects. China＇ s initiatives to construct long-distance natural gas pipelines has brought in new opportunities for the development of X80 line pipes. Baosteel has designed the optimum chemical composition of X80 with high niobium and low molybdenum content. In addition, a welding experimental platform and a finite element model （FEM） have supported the development of X80 UOE pipes in an efficient and economical way. The application and recent development of X80 UOE pipes were introduced in this paper. To comply with the requirements of the Second West-East Gas Pipeline Project （2^nd WEPP ）, X80 pipeline steel with low carbon bainite microstructure was developed by utilizing the optimized composition and TMCP process. The matching welding material, welding procedure and UOE forming processes for 1 219mm outside diameter X80 UOE pipes were also developed. More than 340 000 t of X80 UOE pipes were produced and applied in the 2^nd WEPP. Furthermore, to meet the prospective demand for long-distance gas pipelines with an annual transportation capacity of over 40 billion m3 ,larger size X80 UOE pipes with 1 422 mm OD × 30. 8 mm WT were trial produced recently. DWTT performance, the main technical challenge for heavier wall pipes, was improved by using optimized microstructural design. The newly developed X80 pipes can be potentially used for larger transportation capacity pipelines in China.展开更多
In this paper we investigate the effects of the large extra dimensions on the two processes e＋ e-→＋ H^0 Z^0 Z^0 and e^＋e^-→ H^0H^0 Z^0 at linear colliders in both unpolarized and polarized collision modes. We fin...In this paper we investigate the effects of the large extra dimensions on the two processes e＋ e-→＋ H^0 Z^0 Z^0 and e^＋e^-→ H^0H^0 Z^0 at linear colliders in both unpolarized and polarized collision modes. We find that the virtual Kaluza-Klein graviton exchange can significantly enhance the cross section from their standard model expectations for these two processes. The results show that the LED effect on the process e＋ e-→＋ H^0 Z^0 Z^0 allows the observation limits on the effective scale Ms to be probed up to 9. 75 TeV and 10.1 TeV in the unpolarized and ＋-（λe＋ =1/2, λe-= -1/2） polarized beam collision modes （with Pe＋ = 0.6, Pe-=0.8）, respectively. For the process e＋ e-→＋ H^0 H^0 Z^0, these limits on Ms can be probed up to 6.06 TeV and 6.38 TeV in the unpolarized and polarized collision modes separately. We find that the λe＋ = 1/2, λe-= -1/2 polarization collision mode in both processe＋ e-→＋ H^0 Z^0 Z^0 and e＋ e-→＋ H^0 H^0 Z^0 may provide a possibility to improve the sensitivity in probing the LED effects.展开更多
The author of this paper once attempted to propose a unified framework for gauge fields based on the mathematical and physical picture of the principal fiber bundle: that is, to believe that our universe may have more...The author of this paper once attempted to propose a unified framework for gauge fields based on the mathematical and physical picture of the principal fiber bundle: that is, to believe that our universe may have more fundamental interactions than the four, and these fundamental gauge fields are only components on the bottom manifold (i.e. our universe) projected by a unified gauge potential of the principal fiber bundle manifold;these components can satisfy the transformation of gauge potential, or even be transformed from one basic interaction gauge potential to another basic interaction gauge potential, and can be summarized into a unified equation, namely the generalized gauge equation expression, corresponding to gauge transformation invariance;so the invariance of gauge transformation is a necessary condition for unified field theory, and the four (or more) fundamental interaction fields of the universe are unified in a unified gauge field defined by the connection on the principal fiber bundle. In this paper, the author continues to propose a model of large-scale (gravitational) fundamental interactions in the universe based on the mathematical and physical picture of the principal fiber bundle, attempting to explain that dark matter and dark energy are merely reflections of these gravitational fundamental interactions that deviate in intensity from the gravitational fundamental interactions of the solar system at galaxy scales or some cosmic scales which are much larger than the solar system. All these “gravitational” fundamental interactions originate from the unified gauge field of the universe, namely the connection or curvature on the principal fiber bundle. These interactions are their projected representations on the bottom manifold (i.e. our universe) by different cross-sections (gauge transformations). These projection representations of the universe certainly are described by the generalized gauge equation or curvature similarity equation, and under the guidance of curvature gauge transformation factors, oscillate and evolve between the curvatures 1→0→-1→0→1 of the universe.展开更多
文摘High-strength pipeline steel and large diameter line pipes are often used to increase the capacity of transportation and reduce the cost associated with the construction and operation of long-distance gas pipeline projects. China＇ s initiatives to construct long-distance natural gas pipelines has brought in new opportunities for the development of X80 line pipes. Baosteel has designed the optimum chemical composition of X80 with high niobium and low molybdenum content. In addition, a welding experimental platform and a finite element model （FEM） have supported the development of X80 UOE pipes in an efficient and economical way. The application and recent development of X80 UOE pipes were introduced in this paper. To comply with the requirements of the Second West-East Gas Pipeline Project （2^nd WEPP ）, X80 pipeline steel with low carbon bainite microstructure was developed by utilizing the optimized composition and TMCP process. The matching welding material, welding procedure and UOE forming processes for 1 219mm outside diameter X80 UOE pipes were also developed. More than 340 000 t of X80 UOE pipes were produced and applied in the 2^nd WEPP. Furthermore, to meet the prospective demand for long-distance gas pipelines with an annual transportation capacity of over 40 billion m3 ,larger size X80 UOE pipes with 1 422 mm OD × 30. 8 mm WT were trial produced recently. DWTT performance, the main technical challenge for heavier wall pipes, was improved by using optimized microstructural design. The newly developed X80 pipes can be potentially used for larger transportation capacity pipelines in China.
基金The project supported in part by National Natural Science Foundation of China and the Special Fund of the Chinese Academy of Sciences
文摘In this paper we investigate the effects of the large extra dimensions on the two processes e＋ e-→＋ H^0 Z^0 Z^0 and e^＋e^-→ H^0H^0 Z^0 at linear colliders in both unpolarized and polarized collision modes. We find that the virtual Kaluza-Klein graviton exchange can significantly enhance the cross section from their standard model expectations for these two processes. The results show that the LED effect on the process e＋ e-→＋ H^0 Z^0 Z^0 allows the observation limits on the effective scale Ms to be probed up to 9. 75 TeV and 10.1 TeV in the unpolarized and ＋-（λe＋ =1/2, λe-= -1/2） polarized beam collision modes （with Pe＋ = 0.6, Pe-=0.8）, respectively. For the process e＋ e-→＋ H^0 H^0 Z^0, these limits on Ms can be probed up to 6.06 TeV and 6.38 TeV in the unpolarized and polarized collision modes separately. We find that the λe＋ = 1/2, λe-= -1/2 polarization collision mode in both processe＋ e-→＋ H^0 Z^0 Z^0 and e＋ e-→＋ H^0 H^0 Z^0 may provide a possibility to improve the sensitivity in probing the LED effects.
文摘The author of this paper once attempted to propose a unified framework for gauge fields based on the mathematical and physical picture of the principal fiber bundle: that is, to believe that our universe may have more fundamental interactions than the four, and these fundamental gauge fields are only components on the bottom manifold (i.e. our universe) projected by a unified gauge potential of the principal fiber bundle manifold;these components can satisfy the transformation of gauge potential, or even be transformed from one basic interaction gauge potential to another basic interaction gauge potential, and can be summarized into a unified equation, namely the generalized gauge equation expression, corresponding to gauge transformation invariance;so the invariance of gauge transformation is a necessary condition for unified field theory, and the four (or more) fundamental interaction fields of the universe are unified in a unified gauge field defined by the connection on the principal fiber bundle. In this paper, the author continues to propose a model of large-scale (gravitational) fundamental interactions in the universe based on the mathematical and physical picture of the principal fiber bundle, attempting to explain that dark matter and dark energy are merely reflections of these gravitational fundamental interactions that deviate in intensity from the gravitational fundamental interactions of the solar system at galaxy scales or some cosmic scales which are much larger than the solar system. All these “gravitational” fundamental interactions originate from the unified gauge field of the universe, namely the connection or curvature on the principal fiber bundle. These interactions are their projected representations on the bottom manifold (i.e. our universe) by different cross-sections (gauge transformations). These projection representations of the universe certainly are described by the generalized gauge equation or curvature similarity equation, and under the guidance of curvature gauge transformation factors, oscillate and evolve between the curvatures 1→0→-1→0→1 of the universe.
