A new water soluble surfaCe film-forming material was developed and its effect on reducing ammonia volatilization from an alkaline solution was investigated in laborstory. Results showed that the new film formed by th...A new water soluble surfaCe film-forming material was developed and its effect on reducing ammonia volatilization from an alkaline solution was investigated in laborstory. Results showed that the new film formed by the material was not only more effective in reducing ammonia loss than any other films tested but also much cheaper. The optimum amount of addition of the new film-forming material was about 10times the theoretical amount to form a monomolecular film. Under the experimental conditions, the new film could effectively depress the ammonia volatilization for at least 6 days. The cumulative ammonia loss rates for different films were fitted to a simple logistic equation, and some important parameters such as the cumulative loss, and the maximum and average volatilization rates were calculated. The effect of different films could be, therefore, compared quantitatively, indicating the new film was most effective in depressing ammonia volatilization.展开更多
Y-type zeolite membranes were synthesized by a two-step approach in which a particle seed layer was prepared by electrophoresis deposition(EPD) at first, followed by densification through secondary growth. The pre-see...Y-type zeolite membranes were synthesized by a two-step approach in which a particle seed layer was prepared by electrophoresis deposition(EPD) at first, followed by densification through secondary growth. The pre-seeding adopted the directing agent for Y-type zeolite synthesis serving as seeds. The effects of aging time of the directing agent, electrophoresis voltage and electrophoresis deposition time on seed layers quality as well as the quality of zeolite membranes were investigated. The results indicated that the zeolite seeds derived from the directing agent could be evenly deposited on substrate under certain EPD conditions. The XRD patterns of the seeded substrates after the secondary growth showed that the pure as-synthesized Y-type zeolite membranes had successfully grown on the substrates. The SEM images indicated that the substrate was covered by the highly intergrown zeolite crystals when the seeding solution employed the directing agent with an aging time of 2 days. The separation performance of zeolite membrane was evaluated using a CO_2/N2 mixture(with a mole ratio of 1:1) at different temperatures. Furthermore, the pervaporation measurements were carried out for the dehydration of isopropanol aqueous solutions with different mass fractions. The as-synthesized Y-type zeolite membranes exhibited a relatively high selectivity of water from isopropanol and sustainable permeation flux.展开更多
The fast-growing procedure (FGP) provides a simple, high-yield and lead (Pb)-release free method to prepare perovskite films. In the FGP, the ultra-dilute per- ovskite precursor solution is drop-cast onto a hot (...The fast-growing procedure (FGP) provides a simple, high-yield and lead (Pb)-release free method to prepare perovskite films. In the FGP, the ultra-dilute per- ovskite precursor solution is drop-cast onto a hot (-240℃) substrate where a perovskite film grows immediately ac- companied by the rapid evaporation of the host solvent. In this process, all the raw materials in the precursor solution are deposited into the final perovskite film. The potential pollution caused by Pb can be significantly reduced. Proper- ties of the FGP-processed perovskite films can be modulated by the precursor composition. While CH3NH3CI (MACI) affects the crystallization process and leads to full surface coverage, CH(NHz)2I (FAI) enhances the thermal stability of the film. Based on the optimized precursor composition of PbI2.(1-x)FAI.xMACI, x=0.75, FGP-processed planar het- erojunction perovskite solar cells exhibit power conversion efficiencies (PCEs) exceeding 15% with suppressed hysteresis and excellent reproducibility.展开更多
We have developed a simple method to synthesize 6-seleno-2′-deoxyguanosine(SedG)by selectively replacing the 6-oxygen atom with selenium.This selenium-atom-specific modification(SAM)alters the optical properties of t...We have developed a simple method to synthesize 6-seleno-2′-deoxyguanosine(SedG)by selectively replacing the 6-oxygen atom with selenium.This selenium-atom-specific modification(SAM)alters the optical properties of the naturally occurring2′-deoxyguanosine(dG).Unlike the native dG,the UVabsorption ofSedG is significantly influenced by the pH of the aqueous solution.Moreover,SedG is fluorescent at the physiological pH and exhibits pH-dependent fluorescence in aqueous solutions.Furthermore,SedG has noticeable fluorescence in non-aqueous solutions,indicating its sensitivity to environmental changes.This is the first time a fluorescent nucleoside by single-atom alteration has been observed.Fluorescent nucleosides modified by a single atom have great potential as molecular probes with minimal perturbations to investigate nucleoside interactions with proteins,such as membrane-transporter proteins.展开更多
文摘A new water soluble surfaCe film-forming material was developed and its effect on reducing ammonia volatilization from an alkaline solution was investigated in laborstory. Results showed that the new film formed by the material was not only more effective in reducing ammonia loss than any other films tested but also much cheaper. The optimum amount of addition of the new film-forming material was about 10times the theoretical amount to form a monomolecular film. Under the experimental conditions, the new film could effectively depress the ammonia volatilization for at least 6 days. The cumulative ammonia loss rates for different films were fitted to a simple logistic equation, and some important parameters such as the cumulative loss, and the maximum and average volatilization rates were calculated. The effect of different films could be, therefore, compared quantitatively, indicating the new film was most effective in depressing ammonia volatilization.
基金supported by the Talent Introduction Fund of Yangzhou Universitythe Jiangsu Social Development Project-Science and Technology Support Program(BE2014613)+1 种基金Six Talent Peaks of Jiangsu province(2014-XCL-013)the Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Y-type zeolite membranes were synthesized by a two-step approach in which a particle seed layer was prepared by electrophoresis deposition(EPD) at first, followed by densification through secondary growth. The pre-seeding adopted the directing agent for Y-type zeolite synthesis serving as seeds. The effects of aging time of the directing agent, electrophoresis voltage and electrophoresis deposition time on seed layers quality as well as the quality of zeolite membranes were investigated. The results indicated that the zeolite seeds derived from the directing agent could be evenly deposited on substrate under certain EPD conditions. The XRD patterns of the seeded substrates after the secondary growth showed that the pure as-synthesized Y-type zeolite membranes had successfully grown on the substrates. The SEM images indicated that the substrate was covered by the highly intergrown zeolite crystals when the seeding solution employed the directing agent with an aging time of 2 days. The separation performance of zeolite membrane was evaluated using a CO_2/N2 mixture(with a mole ratio of 1:1) at different temperatures. Furthermore, the pervaporation measurements were carried out for the dehydration of isopropanol aqueous solutions with different mass fractions. The as-synthesized Y-type zeolite membranes exhibited a relatively high selectivity of water from isopropanol and sustainable permeation flux.
基金financially supported by the National Basic Research Program of China (973 Program) (2015CB932203)the National Natural Science Foundation of China (61377025, 91433203, and 11121091)+2 种基金the Young 1000 Talents Global Recruitment Program of Chinasupported by the US Office of Naval Research under contract N00014-15-1-2244the support from the US National Science Foundation (DMR-1305913 and OIA-1538893)
文摘The fast-growing procedure (FGP) provides a simple, high-yield and lead (Pb)-release free method to prepare perovskite films. In the FGP, the ultra-dilute per- ovskite precursor solution is drop-cast onto a hot (-240℃) substrate where a perovskite film grows immediately ac- companied by the rapid evaporation of the host solvent. In this process, all the raw materials in the precursor solution are deposited into the final perovskite film. The potential pollution caused by Pb can be significantly reduced. Proper- ties of the FGP-processed perovskite films can be modulated by the precursor composition. While CH3NH3CI (MACI) affects the crystallization process and leads to full surface coverage, CH(NHz)2I (FAI) enhances the thermal stability of the film. Based on the optimized precursor composition of PbI2.(1-x)FAI.xMACI, x=0.75, FGP-processed planar het- erojunction perovskite solar cells exhibit power conversion efficiencies (PCEs) exceeding 15% with suppressed hysteresis and excellent reproducibility.
基金financially supported by the US National Science Foundation(NSF,MCB-0824837)the Georgia Cancer Coalition(GCC)Distinguished Cancer Clinicians and Scientists Awards
文摘We have developed a simple method to synthesize 6-seleno-2′-deoxyguanosine(SedG)by selectively replacing the 6-oxygen atom with selenium.This selenium-atom-specific modification(SAM)alters the optical properties of the naturally occurring2′-deoxyguanosine(dG).Unlike the native dG,the UVabsorption ofSedG is significantly influenced by the pH of the aqueous solution.Moreover,SedG is fluorescent at the physiological pH and exhibits pH-dependent fluorescence in aqueous solutions.Furthermore,SedG has noticeable fluorescence in non-aqueous solutions,indicating its sensitivity to environmental changes.This is the first time a fluorescent nucleoside by single-atom alteration has been observed.Fluorescent nucleosides modified by a single atom have great potential as molecular probes with minimal perturbations to investigate nucleoside interactions with proteins,such as membrane-transporter proteins.