Phase equilibrium conditions of gas hydrate in several systems were measured by the step-heating method using the cylindrical transparent sapphire cell device.The experimental data for pure CH4 or CO2+deionized water ...Phase equilibrium conditions of gas hydrate in several systems were measured by the step-heating method using the cylindrical transparent sapphire cell device.The experimental data for pure CH4 or CO2+deionized water systems showed good agreement with those in the literatures.This kind of method was then applied to CH4/CO2+sodium dodecyl sulfate(SDS)aqueous solution,CH4/CO2+SDS aqueous solution+silica sand,and(CH4+C2H6+C3H8)gas mixture+SDS aqueous solution systems,where SDS was added to increase the hydrate formation rate without evident influence on the equilibrium conditions.The feasibility and reliability of the step-heating method,especially for porous media systems and gas mixtures systems were determined.The experimental data for CO2+silica sand data shows that the equilibrium pressure will change significantly when the particle size of silica sand is less than 96μm.The formation equilibrium pressure was also measured by the reformation of hydrate.展开更多
This report describes a new three‐component strategy for the regioselective synthesis of a series of tri‐substituted pyridazines via a 1,4‐diazabicyclo[2.2.2]octane （DABCO）‐catalyzed condensation of propiophenon...This report describes a new three‐component strategy for the regioselective synthesis of a series of tri‐substituted pyridazines via a 1,4‐diazabicyclo[2.2.2]octane （DABCO）‐catalyzed condensation of propiophenones, arylglyoxalmonohydrates and hydrazine hydrate in water. This method provides a green and convenient one‐pot route toward a diverse set of 3,6‐diaryl‐4‐methylpyridazines bearing various aryl substituents. This procedure is highly regioselective, operationally simple, uses water as a safe, environmentally friendly solvent, and DABCO as a green base‐organocatalyst, and affords good to excellent yields of products.展开更多
基金Supported by the National Natural Science Foundation of China （20676145, U0633003）, the National Basic Research Program of China （2009CB219504） and the Program for New Century Excellent Talents in University of the State Ministry of Education.
文摘Phase equilibrium conditions of gas hydrate in several systems were measured by the step-heating method using the cylindrical transparent sapphire cell device.The experimental data for pure CH4 or CO2+deionized water systems showed good agreement with those in the literatures.This kind of method was then applied to CH4/CO2+sodium dodecyl sulfate(SDS)aqueous solution,CH4/CO2+SDS aqueous solution+silica sand,and(CH4+C2H6+C3H8)gas mixture+SDS aqueous solution systems,where SDS was added to increase the hydrate formation rate without evident influence on the equilibrium conditions.The feasibility and reliability of the step-heating method,especially for porous media systems and gas mixtures systems were determined.The experimental data for CO2+silica sand data shows that the equilibrium pressure will change significantly when the particle size of silica sand is less than 96μm.The formation equilibrium pressure was also measured by the reformation of hydrate.
基金supported by the Research Council of Payame Noor University
文摘This report describes a new three‐component strategy for the regioselective synthesis of a series of tri‐substituted pyridazines via a 1,4‐diazabicyclo[2.2.2]octane （DABCO）‐catalyzed condensation of propiophenones, arylglyoxalmonohydrates and hydrazine hydrate in water. This method provides a green and convenient one‐pot route toward a diverse set of 3,6‐diaryl‐4‐methylpyridazines bearing various aryl substituents. This procedure is highly regioselective, operationally simple, uses water as a safe, environmentally friendly solvent, and DABCO as a green base‐organocatalyst, and affords good to excellent yields of products.
