TiO2 nanoparticles were synthesized by using micro-reactors. The shape and size of the nanoparticles produced from the original micro-reactors and the five times recycled micro-reactors mother liquor were investigate...TiO2 nanoparticles were synthesized by using micro-reactors. The shape and size of the nanoparticles produced from the original micro-reactors and the five times recycled micro-reactors mother liquor were investigated on transmission electron microscopy (TEM) by using the original sample, freeze prepared sample, and dyeing treated sample, respectively. UV-VIS spectrometry was used to study the growth process of TiO2 nanoparticles in main reactors. The results showed that micro-reactors with nanometer magnitude had spherical or oval structures, and could restore to their original structure after they were destroyed. The products prepared in the original micro-reactors were similar to that in the micro-reactors recycled for many times, suggesting that the micro-reactors had memory function.展开更多
Photocatalysis and Fenton process are two primary and promising advanced oxidation processes to degrade organic pollutants.However,the practical applications of single photocatalysis and Fenton process are still limit...Photocatalysis and Fenton process are two primary and promising advanced oxidation processes to degrade organic pollutants.However,the practical applications of single photocatalysis and Fenton process are still limited.Introducing one of them into another to form a combined photocatalytic Fentonlike system has shown great potential but still faces challenges in designing a well-tailored catalyst.Herein,a confined photocatalytic Fenton-like micro-reactor catalyst with a movable Fe_(3) O_(4) core and a mesoporous TiO_(2) shell has been constructed via a successive Stober coating strategy,followed by an ultrasound assisted etching method.The resulting micro-reactor possesses well-defined yolk-shell structures with unifo rm mesopores(~4 nm),a large Brunauer-Emmett-Teller(BET) surface area(~166.7 m^(2)/g),a high pore volume(~0.56 cm^(3)/g) and a strong magnetization(~51 emu/g),as well as tunable reactor sizes(20-90 nm).When evaluated for degrading bisphenol A under solar light in the presence of peroxymo no sulfate,the micro-reactor exhibits a superior catalytic degradation perfo rmance with a high magnetic separation efficiency and an excellent recycle ability.The outstanding performance can be attributed to its unique textual structure,which leads to a great syne rgistic effect from the photocatalytic and Fenton-like process.This study gives an important insight into the design and synthesis of an advanced micro-reactor for a combined advanced oxidation processes(AOPs).展开更多
High-throughput pyrosequencing,carried out in millions of picoliter-sized reactors on a fiber-optic slide,is known for its longer read length.However,both optical crosstalk(which reduces the signal-to-noise ratio of C...High-throughput pyrosequencing,carried out in millions of picoliter-sized reactors on a fiber-optic slide,is known for its longer read length.However,both optical crosstalk(which reduces the signal-to-noise ratio of CCD images)and chemical retention adversely affect the accuracy of chemiluminescence determination,and ultimately decrease the read length and the accuracy of pyrosequencing results.In this study,both titanium and oxidized aluminum films were deposited on the side walls and upper faces of micro-reactor slides to enhance optical isolation;the films reduced the inter-well crosstalk by one order of magnitude.Subsequently,chemical retention was shown to be caused by the lower diffusion coefficient of the side walls of the picolitersized reactors because of surface roughness and random pores.Optically isolated fiber-optic slides over-coated with silicon oxide showed smoother surface morphology,resulting in little chemical retention;this was further confirmed with theoretical calculations.Picoliter-sized micro-reactors coated with titanium-silicon oxide films showed the least inter-well optical crosstalk and chemical retention;these properties are expected to greatly improve the high-throughput pyrosequencing performance.展开更多
Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports...Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports on an integrated eight-step continuous-flow synthesis of vitamin B_(1) from commercially available 2-cyanoacetamide.The proposed continuous-flow process is based on advances in chemistry,engineering,and equipment design,and affords improved performance and safety compared with batch-mode manufacturing.Several challenges were precisely investigated and controlled,including mixing,unexpected clogging,solvent switches,an exothermic reaction,and the prevention of side reactions,using various micro-channel flow reactors,mixers,separators,and continuous filters.Vitamin B_(1) was produced with a separated yield of 47.7% and high purity,with a total residence time of about 3.5 h.This eight-step continuous-flow protocol enables technology involving up to six of the key principles of green chemistry.Hence,the application of flow technology is of paramount importance for improving security,reducing waste,and,in particular,improving the efficiency of batch operations that require several days for manufacturing.展开更多
文摘TiO2 nanoparticles were synthesized by using micro-reactors. The shape and size of the nanoparticles produced from the original micro-reactors and the five times recycled micro-reactors mother liquor were investigated on transmission electron microscopy (TEM) by using the original sample, freeze prepared sample, and dyeing treated sample, respectively. UV-VIS spectrometry was used to study the growth process of TiO2 nanoparticles in main reactors. The results showed that micro-reactors with nanometer magnitude had spherical or oval structures, and could restore to their original structure after they were destroyed. The products prepared in the original micro-reactors were similar to that in the micro-reactors recycled for many times, suggesting that the micro-reactors had memory function.
基金supported by the National Natural Science Foundation of China (Nos.5182220221972163 and 51772050)the Fundamental Research Funds for the Central Universities (No. 2232020D-02)+7 种基金Shanghai Sailing Program (No.20YF1400500)Shanghai Natural Science Foundation (No.20ZR1401500)Shanghai Rising-Star Program (No.18QA1400100)Youth Top-notch Talent Support Program of Shanghai,Science and Technology Commission of Shanghai Municipality (No.19520713200)Shanghai Scientific and Technological Innovation Project (No. 19JC1410400)Key Basic Research Program of Science and Technology Commission of Shanghai Municipality (No. 20JC1415300)DHU Distinguished Young Professor ProgramFundamental Research Funds for the Central Universities。
文摘Photocatalysis and Fenton process are two primary and promising advanced oxidation processes to degrade organic pollutants.However,the practical applications of single photocatalysis and Fenton process are still limited.Introducing one of them into another to form a combined photocatalytic Fentonlike system has shown great potential but still faces challenges in designing a well-tailored catalyst.Herein,a confined photocatalytic Fenton-like micro-reactor catalyst with a movable Fe_(3) O_(4) core and a mesoporous TiO_(2) shell has been constructed via a successive Stober coating strategy,followed by an ultrasound assisted etching method.The resulting micro-reactor possesses well-defined yolk-shell structures with unifo rm mesopores(~4 nm),a large Brunauer-Emmett-Teller(BET) surface area(~166.7 m^(2)/g),a high pore volume(~0.56 cm^(3)/g) and a strong magnetization(~51 emu/g),as well as tunable reactor sizes(20-90 nm).When evaluated for degrading bisphenol A under solar light in the presence of peroxymo no sulfate,the micro-reactor exhibits a superior catalytic degradation perfo rmance with a high magnetic separation efficiency and an excellent recycle ability.The outstanding performance can be attributed to its unique textual structure,which leads to a great syne rgistic effect from the photocatalytic and Fenton-like process.This study gives an important insight into the design and synthesis of an advanced micro-reactor for a combined advanced oxidation processes(AOPs).
基金supported by the Scientific Equipment Research Project of Chinese Academy of Sciences(YZ200823)
文摘High-throughput pyrosequencing,carried out in millions of picoliter-sized reactors on a fiber-optic slide,is known for its longer read length.However,both optical crosstalk(which reduces the signal-to-noise ratio of CCD images)and chemical retention adversely affect the accuracy of chemiluminescence determination,and ultimately decrease the read length and the accuracy of pyrosequencing results.In this study,both titanium and oxidized aluminum films were deposited on the side walls and upper faces of micro-reactor slides to enhance optical isolation;the films reduced the inter-well crosstalk by one order of magnitude.Subsequently,chemical retention was shown to be caused by the lower diffusion coefficient of the side walls of the picolitersized reactors because of surface roughness and random pores.Optically isolated fiber-optic slides over-coated with silicon oxide showed smoother surface morphology,resulting in little chemical retention;this was further confirmed with theoretical calculations.Picoliter-sized micro-reactors coated with titanium-silicon oxide films showed the least inter-well optical crosstalk and chemical retention;these properties are expected to greatly improve the high-throughput pyrosequencing performance.
基金supported by the Fundamental Research Funds for the Central Universities.
文摘Vitamin B_(1) is widely applied in the healthcare and food industry as an antineuritic and antioxidant to maintain the normal functioning of nerve conduction,the heart,and the gastrointestinal tract.This study reports on an integrated eight-step continuous-flow synthesis of vitamin B_(1) from commercially available 2-cyanoacetamide.The proposed continuous-flow process is based on advances in chemistry,engineering,and equipment design,and affords improved performance and safety compared with batch-mode manufacturing.Several challenges were precisely investigated and controlled,including mixing,unexpected clogging,solvent switches,an exothermic reaction,and the prevention of side reactions,using various micro-channel flow reactors,mixers,separators,and continuous filters.Vitamin B_(1) was produced with a separated yield of 47.7% and high purity,with a total residence time of about 3.5 h.This eight-step continuous-flow protocol enables technology involving up to six of the key principles of green chemistry.Hence,the application of flow technology is of paramount importance for improving security,reducing waste,and,in particular,improving the efficiency of batch operations that require several days for manufacturing.
