An aerobic oxidation of aldehydes towards carboxylic acids in MeCN using 1 atm of pure oxygen or oxygen in air as the oxidant and a catalytic amount of single component catalyst, Fe(NO3)3.9H20, has been developed. C...An aerobic oxidation of aldehydes towards carboxylic acids in MeCN using 1 atm of pure oxygen or oxygen in air as the oxidant and a catalytic amount of single component catalyst, Fe(NO3)3.9H20, has been developed. Carboxylic acids with different synthetically useful functional groups were obtained at room temperature. Two mechanistic pathways have been proposed based on isotopic labeling, NMR monitoring, and control experiments. The practicality of this reaction has been demonstrated by conducting several 50 mmol-scale reactions using pure oxygen or an air-flow of -30 mL/min.展开更多
Metal-free materials with multicolor tunable circularly polarized luminescence(CPL)are attractive because of their potential applications in information storage and encryption.Here,we designed two enantiomers composed...Metal-free materials with multicolor tunable circularly polarized luminescence(CPL)are attractive because of their potential applications in information storage and encryption.Here,we designed two enantiomers composed of chiral dialkyl glutamides and achiral vibration-induced emission(VIE)moiety,which can switch on CPL after a simple gelation process.It is noteworthy that the CPL colors vary in different solvents,and this is attributed to various self-assembly-induced microstructures,in which the VIE moiety is restrained to different degrees.Accordingly,a multidimensional code system composed of a quick response code,a ultraviolet(UV)light-activated color code,and a CPL information figure was constructed.To our satisfaction,the system possesses multiple information-storage functions.The orthogonal anticounterfeiting and CPLenhanced encryption functions also improve the system information encryption ability.In brief,this study provides a practical example of CPL applied to information security and an effective approach to obtain a single-component color-tunable CPL material with multiple information storage and encryption functions as well.展开更多
Metal halide perovskites exhibit promising prospect in light-emitting diodes,solar cells,photodetectors and bioimaging.However,the workhorse of metal halide perovskites relies on toxicity lead element,which severely d...Metal halide perovskites exhibit promising prospect in light-emitting diodes,solar cells,photodetectors and bioimaging.However,the workhorse of metal halide perovskites relies on toxicity lead element,which severely damages human body and environment.Among lead-free perovskites,Cs_(2)NaInCl_(6)double perovskite is one of the most promising candidates because of its great stability and easy synthesis,but suffers inadequate optical performance.Here,we doped Sb^(3+)and Sm^(3+)into Cs_(2)NaInCl_(6)nanocrystals by a hot injection method.Cs_(2)NaInCl_(6):Sb^(3+)exhibits blue emission at 447 nm.Cs_(2)NaInCl_(6):Sm^(3+),Sb^(3+)nanocrystals simultaneously generate the blue emission of Sb^(3+)and the multiple emissions of Sm^(3+)at 565,602,650 and 710 nm.With the increase of Sm^(3+)feed ratio,the emission color of Cs_(2)NaInCl_(6):Sm^(3+),Sb^(3+)gradually moves to cold white region at(0.27,0.28)in CIE chromaticity diagram and correlated color temperature of 11840 K.This work shows the potential application of Cs_(2)NaInCl_(6):Sm^(3+),Sb^(3+)nanocrystals as a single-component cold white emitter.展开更多
To improve the separation performance of a supersonic gas separation device for the treatment of gas mixture with a single heavy component, a novel structure with shorter settlement distance was constructed and a meth...To improve the separation performance of a supersonic gas separation device for the treatment of gas mixture with a single heavy component, a novel structure with shorter settlement distance was constructed and a method of droplet enlargement was applied. A series of experiments were carried out in the improved separation device under various conditions, using air-ethanol vapor as the medium and micro water droplets as nucleation cen- ters. The effects of the inlet pressure, temperature and relative humidity, the swirling intensity, and mass flow rate of water on the separation performance were investigated. The separation was improved by increasing the inlet pressure and relative humidity. With the decrease of swirling intensity and mass flow rate of water, the separation efficiency increased first and then decreased. The inlet temperature had a slight effect on the separation. The results showed that the separation performance was effectively improved using the proposed structure and method, and the best separation in this study was obtained with the ethanol removal rate about 55% and dew point depression 27 K. The addition of water had little pollution to the air-ethanol vapor system since the water carry-over rate was within the range of -2 %-0 in most cases.展开更多
Objective To establish a quality control method for simultaneous determination of multiple components in gamboge. Methods A single reference standard for the determination of multiple components (SSDMC) with HPLC wa...Objective To establish a quality control method for simultaneous determination of multiple components in gamboge. Methods A single reference standard for the determination of multiple components (SSDMC) with HPLC was proposed. Seven major components of gamboge including gambogenic acid (S), β-morellic acid (C1), 2R-30-hydroxygambogic acid (C2), isogambogenic acid (C3), gambogellic acid (C4), 2R-gambogic acid (C5), and 2S-gambogic acid (C6) were simultaneously analyzed using gambogenic acid as reference standard. The credibility and feasibility of SSDMC method were validated with respect to linearity, limits of detection and quantification, precision, stability, repeatability, accuracy, ruggedness, and robustness. The relative conversion factors (RCFs) of S and C1-6 were calculated. Twelve batches of gamboge including crude and processed products were successfully analyzed by applying the SSDMC and traditional external standard (ES) methods. Results The SSDMC method was credible and feasible. The RCFs of S and C1-6 were 1.000, 0.913, 0.864, 1.064, 0.777, 0.921, and 0.919, respectively. No significant difference was observed in the contents of the seven components between SSDMC and ES methods. The heat-processing technique caused a reduction in the seven components. Conclusion SSDMC is a simple, reliable, and effective method for the analysis of the complex multiple components in gamboge, and it is also a practical and economical approach.展开更多
In modern society,information is becoming increasingly interconnected through networks,and the rapid development of information technology has caused people to pay more attention to the encryption and the protection o...In modern society,information is becoming increasingly interconnected through networks,and the rapid development of information technology has caused people to pay more attention to the encryption and the protection of information.Image encryption technology is a key technology for ensuring the security performance of images.We extracted single channel RGB component images from a color image using MATLAB programs,encrypted and decrypted the color images by randomly disrupting rows,columns and regions of the image.Combined with histograms and the visual judgments of encryption images,it is shown that the information of the original image cannot be obtained from the encryption image easily.The results show that the color-image encryptions with the algorithm we used have good effect and fast operation speed.Thus this algorithm has certain practical value.展开更多
In search of biofuel as sustainable energy alternatives for anticipating the gradually decreasing fossil fuel that surely would affect engine performances of industrial machinery as a whole,the research herewith was a...In search of biofuel as sustainable energy alternatives for anticipating the gradually decreasing fossil fuel that surely would affect engine performances of industrial machinery as a whole,the research herewith was aimed to confirm that oil obtained from compressing Sunan pecan seeds(Reutalis trisperma)is the suitable unedible raw oil material to be processed.By carrying out esterification and transesterification processes,the oil became biofuel which consists of various forms of long-chains components of fatty acid methyl ester(FAME).To make it usable for diesel engine,steps of further processes have been done,i.e.,purification and fractionation to produce FAME of single fatty acid components as well as selecting them by PROMETHEE method.The result showed that FAME with single unfractionated fatty acid components was closed to diesel oil characteristics and so the most appropriate biofuel for internal combustion engine.展开更多
Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semico...Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.展开更多
文摘An aerobic oxidation of aldehydes towards carboxylic acids in MeCN using 1 atm of pure oxygen or oxygen in air as the oxidant and a catalytic amount of single component catalyst, Fe(NO3)3.9H20, has been developed. Carboxylic acids with different synthetically useful functional groups were obtained at room temperature. Two mechanistic pathways have been proposed based on isotopic labeling, NMR monitoring, and control experiments. The practicality of this reaction has been demonstrated by conducting several 50 mmol-scale reactions using pure oxygen or an air-flow of -30 mL/min.
基金support from the National Key Research and Development Program of China(grant no.2022YFB3203500)the National Natural Science Foundation of China(grant nos.21788102,22125803,and 22020102006)+2 种基金project support by the Shanghai Municipal Science and Technology Major Project(grant no.2018SHZDZX03)the Program of Shanghai Academic/Technology Research Leader(grant no.20XD1421300)the Fundamental Research Funds for the Central Universities.
文摘Metal-free materials with multicolor tunable circularly polarized luminescence(CPL)are attractive because of their potential applications in information storage and encryption.Here,we designed two enantiomers composed of chiral dialkyl glutamides and achiral vibration-induced emission(VIE)moiety,which can switch on CPL after a simple gelation process.It is noteworthy that the CPL colors vary in different solvents,and this is attributed to various self-assembly-induced microstructures,in which the VIE moiety is restrained to different degrees.Accordingly,a multidimensional code system composed of a quick response code,a ultraviolet(UV)light-activated color code,and a CPL information figure was constructed.To our satisfaction,the system possesses multiple information-storage functions.The orthogonal anticounterfeiting and CPLenhanced encryption functions also improve the system information encryption ability.In brief,this study provides a practical example of CPL applied to information security and an effective approach to obtain a single-component color-tunable CPL material with multiple information storage and encryption functions as well.
基金Project supported by the National Natural Science Foundation of China(62104062)the China Postdoctoral Science Foundation(2021M701056)。
文摘Metal halide perovskites exhibit promising prospect in light-emitting diodes,solar cells,photodetectors and bioimaging.However,the workhorse of metal halide perovskites relies on toxicity lead element,which severely damages human body and environment.Among lead-free perovskites,Cs_(2)NaInCl_(6)double perovskite is one of the most promising candidates because of its great stability and easy synthesis,but suffers inadequate optical performance.Here,we doped Sb^(3+)and Sm^(3+)into Cs_(2)NaInCl_(6)nanocrystals by a hot injection method.Cs_(2)NaInCl_(6):Sb^(3+)exhibits blue emission at 447 nm.Cs_(2)NaInCl_(6):Sm^(3+),Sb^(3+)nanocrystals simultaneously generate the blue emission of Sb^(3+)and the multiple emissions of Sm^(3+)at 565,602,650 and 710 nm.With the increase of Sm^(3+)feed ratio,the emission color of Cs_(2)NaInCl_(6):Sm^(3+),Sb^(3+)gradually moves to cold white region at(0.27,0.28)in CIE chromaticity diagram and correlated color temperature of 11840 K.This work shows the potential application of Cs_(2)NaInCl_(6):Sm^(3+),Sb^(3+)nanocrystals as a single-component cold white emitter.
基金Supported by the Natural Science Foundation of Liaoning Province, China (20052193) and Ph.D. Programs Foundation of Ministry of Education o f China (20070141045).
文摘To improve the separation performance of a supersonic gas separation device for the treatment of gas mixture with a single heavy component, a novel structure with shorter settlement distance was constructed and a method of droplet enlargement was applied. A series of experiments were carried out in the improved separation device under various conditions, using air-ethanol vapor as the medium and micro water droplets as nucleation cen- ters. The effects of the inlet pressure, temperature and relative humidity, the swirling intensity, and mass flow rate of water on the separation performance were investigated. The separation was improved by increasing the inlet pressure and relative humidity. With the decrease of swirling intensity and mass flow rate of water, the separation efficiency increased first and then decreased. The inlet temperature had a slight effect on the separation. The results showed that the separation performance was effectively improved using the proposed structure and method, and the best separation in this study was obtained with the ethanol removal rate about 55% and dew point depression 27 K. The addition of water had little pollution to the air-ethanol vapor system since the water carry-over rate was within the range of -2 %-0 in most cases.
基金Science and Technology Commission of Shanghai Municipality(13ZR1442000)Shanghai Municipal Education Commission(2014YSN20)Support Program
文摘Objective To establish a quality control method for simultaneous determination of multiple components in gamboge. Methods A single reference standard for the determination of multiple components (SSDMC) with HPLC was proposed. Seven major components of gamboge including gambogenic acid (S), β-morellic acid (C1), 2R-30-hydroxygambogic acid (C2), isogambogenic acid (C3), gambogellic acid (C4), 2R-gambogic acid (C5), and 2S-gambogic acid (C6) were simultaneously analyzed using gambogenic acid as reference standard. The credibility and feasibility of SSDMC method were validated with respect to linearity, limits of detection and quantification, precision, stability, repeatability, accuracy, ruggedness, and robustness. The relative conversion factors (RCFs) of S and C1-6 were calculated. Twelve batches of gamboge including crude and processed products were successfully analyzed by applying the SSDMC and traditional external standard (ES) methods. Results The SSDMC method was credible and feasible. The RCFs of S and C1-6 were 1.000, 0.913, 0.864, 1.064, 0.777, 0.921, and 0.919, respectively. No significant difference was observed in the contents of the seven components between SSDMC and ES methods. The heat-processing technique caused a reduction in the seven components. Conclusion SSDMC is a simple, reliable, and effective method for the analysis of the complex multiple components in gamboge, and it is also a practical and economical approach.
基金National Natural Science Foundation of China(No.11865013)Horizontal Project of Shangrao Normal University,China(No.K8000219T)+1 种基金Industrial Science and Technology Project in Shangrao of Jiangxi Province,China(No.17A005)Doctoral Scientific Research Foundation of Shangrao Normal University,China(No.6000108)。
文摘In modern society,information is becoming increasingly interconnected through networks,and the rapid development of information technology has caused people to pay more attention to the encryption and the protection of information.Image encryption technology is a key technology for ensuring the security performance of images.We extracted single channel RGB component images from a color image using MATLAB programs,encrypted and decrypted the color images by randomly disrupting rows,columns and regions of the image.Combined with histograms and the visual judgments of encryption images,it is shown that the information of the original image cannot be obtained from the encryption image easily.The results show that the color-image encryptions with the algorithm we used have good effect and fast operation speed.Thus this algorithm has certain practical value.
文摘In search of biofuel as sustainable energy alternatives for anticipating the gradually decreasing fossil fuel that surely would affect engine performances of industrial machinery as a whole,the research herewith was aimed to confirm that oil obtained from compressing Sunan pecan seeds(Reutalis trisperma)is the suitable unedible raw oil material to be processed.By carrying out esterification and transesterification processes,the oil became biofuel which consists of various forms of long-chains components of fatty acid methyl ester(FAME).To make it usable for diesel engine,steps of further processes have been done,i.e.,purification and fractionation to produce FAME of single fatty acid components as well as selecting them by PROMETHEE method.The result showed that FAME with single unfractionated fatty acid components was closed to diesel oil characteristics and so the most appropriate biofuel for internal combustion engine.
基金supported by the National Key Research and Development Program of China(No.2022YFB4200600)the National Natural Science Foundation of China(Nos.52173185 and 52127806)+1 种基金the Fundamental Research Funds for the Central Universities(Nos.226-2022-00133 and 226-2022-00209)L.Z.thanks the research start-up fund from Zhejiang University.
文摘Since 1986,the donor-acceptor (D:A) heterojunction has been regarded a necessity for high-efficiency organic photovoltaics (OPVs),due to its unique advantage in compensating the intrinsic limitations of organic semiconductors,such as high exciton binding energy and poor ambipolar charge mobility. While this adversely causes tremendous non-radiative charge recombination and instability issues,which currently become the most critical limits for commercialization of OPVs. Here,we present a concept-to-proof study on the potential of D:A heterojunction free OPV by taking advantage of recent progress of non-fullerene acceptors. First,we demonstrate that the “free carriers” can be spontaneously generated upon illumination in an NFA,i.e.,the 6TIC-4F single layer. Second,the 6TIC-4F layer also exhibits good ambipolar charge transporting property. These exceptional characteristics distinguish it from the traditional organic semiconductors,and relieve it from the reliance of D:A heterojunction to independently work as active layer. As a result,the subsequent OPV by simply sandwiching the 6TIC-4F layer between the cathode and anode yields a considerably high power conversion efficiency ~1%. Moreover,we find the D:A heterojunction free device exhibits two order of magnitude higher electroluminescence quantum efficiency and significantly reduced VOC loss by 0.16 eV compared to those of the D:A BHJ structure,validating its promise for higher efficiency in the future. Therefore,our work demonstrates the possibility of using D:A heterojunction-free device structure for high performance,that can potentially become the next game changer of OPV.