The aim was to develop films with a new mixture of collagen fiber plus polyvinyl alcohol added of oregano or rosemary essential oils at different levels (0%, 2%, 4% and 6%), as well as to assess the antimicrobial acti...The aim was to develop films with a new mixture of collagen fiber plus polyvinyl alcohol added of oregano or rosemary essential oils at different levels (0%, 2%, 4% and 6%), as well as to assess the antimicrobial activity, physical, optical, microstructure and molecular properties in the films. An interaction between the ingredients was observed at the molecular level by FTIR. The amide II and amide III bands, which are important to verify collagen conformation, showed intense peaks in the films. The formation of a network through collagen fibers was produced, acting as a reinforcement in matrix. The films with essential oil had an expressive antimicrobial activity by the steam contact method (micro-atmosphere), mainly for Escherichia coli and Staphylococcus aureus. The mixture of collagen fiber plus polyvinyl alcohol added of essential oils is a promising matrix for application in food as active packaging.展开更多
A new highly sensitive method (detection limit: 4.1 ag spofx, sample volume: 0.4 gL spot^·l) for the determination of trace Hg2^2+ by catalytic solid substrate-room temperature phosphorimetry has been establ...A new highly sensitive method (detection limit: 4.1 ag spofx, sample volume: 0.4 gL spot^·l) for the determination of trace Hg2^2+ by catalytic solid substrate-room temperature phosphorimetry has been established in this paper. This method has been successfully applied to determine trace Hg6^2+ in water.展开更多
An acetic acid-promoted C(sp^(3))-H functionalization of 2-methyl quinoline,enaminoesters and elemental sulfur for the synthesis of 3,4,5-trisubstituted isothiazoles under metal-free conditions has been developed.This...An acetic acid-promoted C(sp^(3))-H functionalization of 2-methyl quinoline,enaminoesters and elemental sulfur for the synthesis of 3,4,5-trisubstituted isothiazoles under metal-free conditions has been developed.This approach provides viable access to various 5-(quinolin-2-yl)isothiazoles in moderate to good yields with good functional group tolerance.Moreover,the success of the gram-scale reaction gives this reaction a great potential application.展开更多
Photocatalysis as an emerging "green" energy conversion technology has attracted domestic and international attention.This technology uses semiconductor photocatalysts to convert solar energy into directly u...Photocatalysis as an emerging "green" energy conversion technology has attracted domestic and international attention.This technology uses semiconductor photocatalysts to convert solar energy into directly usable chemical energy,showing great potential for application in environmental pollutant purification and clean energy production,with broad development prospects.Among many semiconductor materials,tungsten trioxide(WO_(3)) is favored by researchers in the field of photocatalysis because of its good visible light response and excellent valence band hole oxidation properties.Currently,a large number of photocatalysts based on WO_(3),in particular W03-based composite photocatalysts,have been reported,and their applications cover a wide range of fields.In order to promote the development of WO_(3)-based photocatalysts and provide a reference for colleagues,we present a systematic summary of the applications and research progress of W03-based composites in the field of photocatalysis in recent years.Starting from the structural properties of WO_(3)itself,this article summarizes the preparation methods and structure-activity relationships of WO_(3)-based composite photocatalysts.Subsequently,it introduces the current application status of existing WO_(3)-based composite photocatalysts in CO_(2) reduction,hydrogen production,nitrogen fixation,and pollutant removal.Finally,the development prospects were analyzed.展开更多
文摘The aim was to develop films with a new mixture of collagen fiber plus polyvinyl alcohol added of oregano or rosemary essential oils at different levels (0%, 2%, 4% and 6%), as well as to assess the antimicrobial activity, physical, optical, microstructure and molecular properties in the films. An interaction between the ingredients was observed at the molecular level by FTIR. The amide II and amide III bands, which are important to verify collagen conformation, showed intense peaks in the films. The formation of a network through collagen fibers was produced, acting as a reinforcement in matrix. The films with essential oil had an expressive antimicrobial activity by the steam contact method (micro-atmosphere), mainly for Escherichia coli and Staphylococcus aureus. The mixture of collagen fiber plus polyvinyl alcohol added of essential oils is a promising matrix for application in food as active packaging.
基金supported by Fujian Province Natural Science Foundation(No.C 0510028,D 0510027).
文摘A new highly sensitive method (detection limit: 4.1 ag spofx, sample volume: 0.4 gL spot^·l) for the determination of trace Hg2^2+ by catalytic solid substrate-room temperature phosphorimetry has been established in this paper. This method has been successfully applied to determine trace Hg6^2+ in water.
基金Support by the National Natural Science Foundation of China(Nos.22271244,21871226 and 21572194)Postgraduate Scientific Research Innovation Project of Hunan Province(No.CX20200631)the Open Research Fund of the School of Chemistry and Chemical Engineering of Henan Normal University(No.2022C02)is gratefully acknowledged.
文摘An acetic acid-promoted C(sp^(3))-H functionalization of 2-methyl quinoline,enaminoesters and elemental sulfur for the synthesis of 3,4,5-trisubstituted isothiazoles under metal-free conditions has been developed.This approach provides viable access to various 5-(quinolin-2-yl)isothiazoles in moderate to good yields with good functional group tolerance.Moreover,the success of the gram-scale reaction gives this reaction a great potential application.
基金financially supported by the National Natural Science Foundation of China (No.22376051)the China Postdoctoral Science Foundation (Nos.2021T140512 and 2020M680869)the Natural Science Foundation of Hebei Province (No.B2021202001)。
文摘Photocatalysis as an emerging "green" energy conversion technology has attracted domestic and international attention.This technology uses semiconductor photocatalysts to convert solar energy into directly usable chemical energy,showing great potential for application in environmental pollutant purification and clean energy production,with broad development prospects.Among many semiconductor materials,tungsten trioxide(WO_(3)) is favored by researchers in the field of photocatalysis because of its good visible light response and excellent valence band hole oxidation properties.Currently,a large number of photocatalysts based on WO_(3),in particular W03-based composite photocatalysts,have been reported,and their applications cover a wide range of fields.In order to promote the development of WO_(3)-based photocatalysts and provide a reference for colleagues,we present a systematic summary of the applications and research progress of W03-based composites in the field of photocatalysis in recent years.Starting from the structural properties of WO_(3)itself,this article summarizes the preparation methods and structure-activity relationships of WO_(3)-based composite photocatalysts.Subsequently,it introduces the current application status of existing WO_(3)-based composite photocatalysts in CO_(2) reduction,hydrogen production,nitrogen fixation,and pollutant removal.Finally,the development prospects were analyzed.