The removal of a volatile organic compound (VOC) from high viscous liquid was carried out in a rotat-ing packed bed (RPB) in this study. The mixed liquid of syrup and acetone was used as simulated high viscous polymer...The removal of a volatile organic compound (VOC) from high viscous liquid was carried out in a rotat-ing packed bed (RPB) in this study. The mixed liquid of syrup and acetone was used as simulated high viscous polymer solution with acetone as the volatile compound. The influence of the rotating speed of RPB, liquid viscos-ity, liquid flow rate, vacuum degree, and initial acetone content in the liquid on acetone removal efficiency was in-vestigated. The experimental results indicated that the removal efficiency increased with increasing rotating speed and initial acetone content in the viscous liquid and decreased with increasing liquid viscosity and flow rate. It was also observed that acetone removal efficiency increased with an increasing vacuum degree and reached 58% at a vacuum degree of 0.1 MPa. By the comparison with a flash tank devolatilizer, it was found that acetone removal ef-ficiency in RPB increased by about 67%.展开更多
The dispersion processes and methods of physical sun-screening agents in liquid medium were briefed.Several stabilizing mechanisms of ultrafine particle in liquid medium was introduced, and the stabilizing mechanisms ...The dispersion processes and methods of physical sun-screening agents in liquid medium were briefed.Several stabilizing mechanisms of ultrafine particle in liquid medium was introduced, and the stabilizing mechanisms of physical sunscreens were discussed. At last, the currently existing evaluation methods of physical sun-screening slurry stability were also illustrated.展开更多
Syntheses of 3-substituted coumarins by the condensation reaction of salicylaldehyde with activated methylene compounds (ethyl cyanoacetate, malonic acid) are discussed in media of ionic liquids--(2-hydroxyethyl)a...Syntheses of 3-substituted coumarins by the condensation reaction of salicylaldehyde with activated methylene compounds (ethyl cyanoacetate, malonic acid) are discussed in media of ionic liquids--(2-hydroxyethyl)ammonium carboxylates (formates, acetates, lactates) without utilization of any other catalysts. The dependence of yields of the reaction product is investigated on the structure of ionic liquids (their cations, anions, total polarity and pseudo-pH values). 3-Substituted coumarins are prepared in high yields in media of these environmentally friendly ionic liquids which serve simultaneously as reaction media and as catalysts. The mentioned ionic liquids are prepared by reactions of corresponding hydroxyethyl-amines with carboxylic acids, and their quantitative analyses being made by potentiometric titration of ionic liquids with perchloric acid in 100% acetic acid.展开更多
A simple and ef ficient method is proposed for the synthesis of tetrahydrobenzo[b]pyrans with aromatic aldehydes, active methylene compounds, and dimedone using basic ionic liquid catalyst in water. The procedure offe...A simple and ef ficient method is proposed for the synthesis of tetrahydrobenzo[b]pyrans with aromatic aldehydes, active methylene compounds, and dimedone using basic ionic liquid catalyst in water. The procedure offers several advantages including short reaction time, good yield, easy procedure, and good recyclability of catalysts, which may be a practical alternative to conventional processes for preparation of 4-hpyrans.展开更多
This paper thoroughly studies the'. process of obtaining sulfur nanoparticles in aqueous medium from sodium polysulfide. Nanosize sulfur particles with orthorhombic structure were obtained at room temperature by mixi...This paper thoroughly studies the'. process of obtaining sulfur nanoparticles in aqueous medium from sodium polysulfide. Nanosize sulfur particles with orthorhombic structure were obtained at room temperature by mixing sodium polysulfide aqueous solution with various inorganic and organic acids. Sulfur nanoparticles were characterized by laser particle-size analyzer, X-ray diffraction, electron probe microscopy. Size of sulfur nanoparticles in aqueous dispersion is affected ;trongly by acid concentration, as well as nature of alcohols, used as wetting agents when measuring sulfur particles size iin aqueous medium. Availability of obtaining sulfur nanoparticles of 22-25 nm average si;,e in aqueous medium was revealed. High biological activity of sulfur nanoparticles and ethylalcohol composition on wheat grain couching was established.展开更多
UO2+, which is extracted from the aqueous phase into the 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(C2mim NTf2) ionic liquid ph^ase with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine o...UO2+, which is extracted from the aqueous phase into the 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(C2mim NTf2) ionic liquid ph^ase with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide(CMPO), can be stripped by supercritical CO2. Trioctylphosphine oxide(TOPO), the modifier added to the supercritical CO2 phase, enhances the stripping efficiency by up to 99%.展开更多
The rational design and construction of inexpensive and highly active electrocatalysts for hydrogen evolution reaction(HER)is of great importance for water splitting.Herein,we develop a facile approach for preparation...The rational design and construction of inexpensive and highly active electrocatalysts for hydrogen evolution reaction(HER)is of great importance for water splitting.Herein,we develop a facile approach for preparation of porous carbon-confined Ru-doped Cu nanoparticles(denoted as Ru-Cu@C)by direct pyrolysis of the Ru-exchanged Cu-BTC metal–organic framework.When served as the electrocatalyst for HER,strikingly,the obtained Ru-Cu@C catalyst exhibits an ultralow overpotential(only 20 mV at 10 mA cm^(-2))with a small Tafel slope of 37 m V dec^(-1)in alkaline electrolyte.The excellent performance is comparable or even superior to that of commercial Pt/C catalyst.Density functional theory(DFT)calculations confirm that introducing Ru atoms into Cu nanocrystals can significantly alter the desorption of H_(2) to achieve a close-to-zero hydrogen adsorption energy and thereby boost the HER process.This strategy gives a fresh impetus to explore low-cost and high-performance catalysts for HER in alkaline media.展开更多
基金Supported by the National Natural Science Foundation of China (20821004)the National High Technology Research and Development Program of China (2006AA030202)the Program for New Century Excellent Talents in University of China(NCET-07-0053)
文摘The removal of a volatile organic compound (VOC) from high viscous liquid was carried out in a rotat-ing packed bed (RPB) in this study. The mixed liquid of syrup and acetone was used as simulated high viscous polymer solution with acetone as the volatile compound. The influence of the rotating speed of RPB, liquid viscos-ity, liquid flow rate, vacuum degree, and initial acetone content in the liquid on acetone removal efficiency was in-vestigated. The experimental results indicated that the removal efficiency increased with increasing rotating speed and initial acetone content in the viscous liquid and decreased with increasing liquid viscosity and flow rate. It was also observed that acetone removal efficiency increased with an increasing vacuum degree and reached 58% at a vacuum degree of 0.1 MPa. By the comparison with a flash tank devolatilizer, it was found that acetone removal ef-ficiency in RPB increased by about 67%.
文摘The dispersion processes and methods of physical sun-screening agents in liquid medium were briefed.Several stabilizing mechanisms of ultrafine particle in liquid medium was introduced, and the stabilizing mechanisms of physical sunscreens were discussed. At last, the currently existing evaluation methods of physical sun-screening slurry stability were also illustrated.
文摘Syntheses of 3-substituted coumarins by the condensation reaction of salicylaldehyde with activated methylene compounds (ethyl cyanoacetate, malonic acid) are discussed in media of ionic liquids--(2-hydroxyethyl)ammonium carboxylates (formates, acetates, lactates) without utilization of any other catalysts. The dependence of yields of the reaction product is investigated on the structure of ionic liquids (their cations, anions, total polarity and pseudo-pH values). 3-Substituted coumarins are prepared in high yields in media of these environmentally friendly ionic liquids which serve simultaneously as reaction media and as catalysts. The mentioned ionic liquids are prepared by reactions of corresponding hydroxyethyl-amines with carboxylic acids, and their quantitative analyses being made by potentiometric titration of ionic liquids with perchloric acid in 100% acetic acid.
基金Supported by the Zhejiang Provincial Natural Science Foundation of China(LY15B060002)the National Natural Science Foundation of China(21106090,21272169,21471110)the National Undergraduate Programs for Innovation and Entrepreneurship(201410350018)
文摘A simple and ef ficient method is proposed for the synthesis of tetrahydrobenzo[b]pyrans with aromatic aldehydes, active methylene compounds, and dimedone using basic ionic liquid catalyst in water. The procedure offers several advantages including short reaction time, good yield, easy procedure, and good recyclability of catalysts, which may be a practical alternative to conventional processes for preparation of 4-hpyrans.
文摘This paper thoroughly studies the'. process of obtaining sulfur nanoparticles in aqueous medium from sodium polysulfide. Nanosize sulfur particles with orthorhombic structure were obtained at room temperature by mixing sodium polysulfide aqueous solution with various inorganic and organic acids. Sulfur nanoparticles were characterized by laser particle-size analyzer, X-ray diffraction, electron probe microscopy. Size of sulfur nanoparticles in aqueous dispersion is affected ;trongly by acid concentration, as well as nature of alcohols, used as wetting agents when measuring sulfur particles size iin aqueous medium. Availability of obtaining sulfur nanoparticles of 22-25 nm average si;,e in aqueous medium was revealed. High biological activity of sulfur nanoparticles and ethylalcohol composition on wheat grain couching was established.
基金supported by the National Natural Science Foundation of China(91226112)
文摘UO2+, which is extracted from the aqueous phase into the 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(C2mim NTf2) ionic liquid ph^ase with octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide(CMPO), can be stripped by supercritical CO2. Trioctylphosphine oxide(TOPO), the modifier added to the supercritical CO2 phase, enhances the stripping efficiency by up to 99%.
基金the National Key R&D Program of China(2018YFB0605700)the National Natural Science Foundation of China(51778570,51879230,21725101,21871244,21521001,and 21703145)+1 种基金China Postdoctoral Science Foundation(2019TQ0298,2019M660151)Fujian Institute of Innovation(CAS)。
文摘The rational design and construction of inexpensive and highly active electrocatalysts for hydrogen evolution reaction(HER)is of great importance for water splitting.Herein,we develop a facile approach for preparation of porous carbon-confined Ru-doped Cu nanoparticles(denoted as Ru-Cu@C)by direct pyrolysis of the Ru-exchanged Cu-BTC metal–organic framework.When served as the electrocatalyst for HER,strikingly,the obtained Ru-Cu@C catalyst exhibits an ultralow overpotential(only 20 mV at 10 mA cm^(-2))with a small Tafel slope of 37 m V dec^(-1)in alkaline electrolyte.The excellent performance is comparable or even superior to that of commercial Pt/C catalyst.Density functional theory(DFT)calculations confirm that introducing Ru atoms into Cu nanocrystals can significantly alter the desorption of H_(2) to achieve a close-to-zero hydrogen adsorption energy and thereby boost the HER process.This strategy gives a fresh impetus to explore low-cost and high-performance catalysts for HER in alkaline media.