A Weierstrass Representation Formula for Minimal Surfaces in HS and H2×R Francesco MERCURI Stefano MONTALDO Paola PIU We give a general setting for constructing a Weierstrass representation formula for simply con...A Weierstrass Representation Formula for Minimal Surfaces in HS and H2×R Francesco MERCURI Stefano MONTALDO Paola PIU We give a general setting for constructing a Weierstrass representation formula for simply connected minimal surfaces in a Riemannian manifold. Then, we construct examples of minimal surfaces in the three dimensional Heisenberg group and in the product of the hyperbolic plane with the real line.展开更多
Debates & IdeasNo.106 Power,Society,and Living Space:Evolution and Formation Mechanism of Urban Streets in China/Jiayan LIU,Xiangyu DENG15 Spatial Logic and Risks in China’s Rapid Urbanization under Global Comple...Debates & IdeasNo.106 Power,Society,and Living Space:Evolution and Formation Mechanism of Urban Streets in China/Jiayan LIU,Xiangyu DENG15 Spatial Logic and Risks in China’s Rapid Urbanization under Global Complexity/Dongfeng YANGNo.206 Formation Mechanism of the Cluster Space of Wuhan Metropolitan Area amid Evolution of Power Relationship/Yan FENG,Jianwei YE,Yaping HUANG15 Study on Gregarious Low-Income College Graduates in Beijing:Tangjialing Phenomenon and Its Aftereffect/Chaolin GU,Mingjie SHENG,Lingqian展开更多
The objective of the present study is an experimental investigation of diffusion combustion of round microjets,i.e.,mixtures of hydrogen with methane,helium,and nitrogen.It is found that the evolution of burning micro...The objective of the present study is an experimental investigation of diffusion combustion of round microjets,i.e.,mixtures of hydrogen with methane,helium,and nitrogen.It is found that the evolution of burning microjets is associated with generation of a“bottleneck flame region”close to the nozzle exit,as it was observed earlier during hydrogen combustion.Combustion of a mixture of hydrogen and methane with increasing flow velocity occurs with the transformation of the torch.At first,a torch stabilized on the nozzle is observed,then it is divided into a stabilized part in contact with the nozzle and into a raised part of the torch.The combustion process occurs in two areas.A further increase in velocity promotes the breakdown of the raised torch,but maintains combustion in the nozzle area.The results on hydrogen/methane combustion are obtained in a smaller range of the microjet velocity than those of a hydrogen microjet.Somewhat similar data are derived for other gas additives.To make combustion of gas mixtures more stable with increasing microjet velocity,one has to increase the portion of hydrogen in the gas mixture or reduce the fractions of other gas additives.展开更多
文摘A Weierstrass Representation Formula for Minimal Surfaces in HS and H2×R Francesco MERCURI Stefano MONTALDO Paola PIU We give a general setting for constructing a Weierstrass representation formula for simply connected minimal surfaces in a Riemannian manifold. Then, we construct examples of minimal surfaces in the three dimensional Heisenberg group and in the product of the hyperbolic plane with the real line.
文摘Debates & IdeasNo.106 Power,Society,and Living Space:Evolution and Formation Mechanism of Urban Streets in China/Jiayan LIU,Xiangyu DENG15 Spatial Logic and Risks in China’s Rapid Urbanization under Global Complexity/Dongfeng YANGNo.206 Formation Mechanism of the Cluster Space of Wuhan Metropolitan Area amid Evolution of Power Relationship/Yan FENG,Jianwei YE,Yaping HUANG15 Study on Gregarious Low-Income College Graduates in Beijing:Tangjialing Phenomenon and Its Aftereffect/Chaolin GU,Mingjie SHENG,Lingqian
基金carried out with the financial support of the Ministry of Science and Higher Education of the Russian Federation,Agreement dated 24.04.2024,No.075-15-2024-543.
文摘The objective of the present study is an experimental investigation of diffusion combustion of round microjets,i.e.,mixtures of hydrogen with methane,helium,and nitrogen.It is found that the evolution of burning microjets is associated with generation of a“bottleneck flame region”close to the nozzle exit,as it was observed earlier during hydrogen combustion.Combustion of a mixture of hydrogen and methane with increasing flow velocity occurs with the transformation of the torch.At first,a torch stabilized on the nozzle is observed,then it is divided into a stabilized part in contact with the nozzle and into a raised part of the torch.The combustion process occurs in two areas.A further increase in velocity promotes the breakdown of the raised torch,but maintains combustion in the nozzle area.The results on hydrogen/methane combustion are obtained in a smaller range of the microjet velocity than those of a hydrogen microjet.Somewhat similar data are derived for other gas additives.To make combustion of gas mixtures more stable with increasing microjet velocity,one has to increase the portion of hydrogen in the gas mixture or reduce the fractions of other gas additives.
