1,566 results on '"School of Chemistry and Environment"'
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2. Accurate and efficient calculation of excitation energies with the active-space particle-particle random phase approximation
- Author
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Yang, Weitao [Duke Univ., Durham, NC (United States); South China Normal Univ., Guangzhou (China). School of Chemistry and Environment]
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- 2016
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3. Conical Intersections from Particle–Particle Random Phase and Tamm–Dancoff Approximations
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Yang, Weitao [Duke Univ., Durham, NC (United States). Dept. of Chemistry, and Dept. of Physics; South China Normal Univ., Guangzhou (China). Key Lab. of Theoretical Chemistry of Environment, Ministry of Education, School of Chemistry and Environment]
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- 2016
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4. Improved dispersion of carbon nanotubes in poly(vinylidene fluoride) composites by hybrids with core-shell structure
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Yuan Deng, Xiying Zhou, Benhui Fan, Xiaoxin Lu, Delong He, Jinbo Bai, Zhi-Min Dang, Laboratoire de mécanique des sols, structures et matériaux (MSSMat), CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Department of Polymer Science and Engineering (USTB), University of Science and Technology Beijing [Beijing] (USTB), School of Chemistry and Environment, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, and School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China-School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China
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Materials science ,Polymers and Plastics ,Composite number ,Nanoparticle ,02 engineering and technology ,Carbon nanotube ,Thermal treatment ,Conductivity ,010402 general chemistry ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,law ,Materials Chemistry ,Composite material ,ComputingMilieux_MISCELLANEOUS ,Percolation threshold ,General Chemistry ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Surfaces, Coatings and Films ,chemistry ,[PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] ,0210 nano-technology ,Dispersion (chemistry) ,Fluoride - Abstract
Core–shell structure hybrids of carbon nanotubes (CNTs)/BaTiO3 (H-CNT-BT) and commercial multi-wall CNTs are respectively incorporated into poly(vinylidene fluoride) (PVDF) for preparing the composites near the percolation thresholds. A comprehensive investigation for CNT's dispersion and composite's conductivity is conducted between H-CNT-BT/PVDF and CNT/PVDF at different depths vertical to the injection's direction. Gradual increases of the conductivity in two composites are observed from the out-layer to the core part which infers an inhomogeneous CNT's dispersion in the interior of composites due to their migration under flow during the injection. However, the use of H-CNT-BT fillers with core–shell structure enables to reduce this inhomogeneous dispersion in the composite. Furthermore, the conductive network of CNTs in H-CNT-BT/PVDF is less sensitive to the thermal treatment than the one in CNT/PVDF composite, which infers the core–shell structure of hybrids can ameliorate the sensitivity of the conductive network. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45693.
- Published
- 2018
5. A facile way to fabricate novel 2–3-type composites based on zinc powders and polyvinylidene fluoride with enhanced dielectric properties
- Author
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Jinkai Yuan, Yuan Deng, Mao Li, Jinbo Bai, Ye Zhang, Yao Wang, School of Chemistry and Environment, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China-School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, Laboratoire de mécanique des sols, structures et matériaux (MSSMat), and CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)
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010302 applied physics ,chemistry.chemical_classification ,Materials science ,chemistry.chemical_element ,02 engineering and technology ,Polymer ,Dielectric ,Zinc ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Polyvinylidene fluoride ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,0103 physical sciences ,Ceramics and Composites ,Thermal stability ,Dielectric loss ,[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics ,Composite material ,0210 nano-technology ,ComputingMilieux_MISCELLANEOUS - Abstract
This study describes a simple and low-cost method for fabricating novel 2–3-type composites composed of zinc flakes and polyvinylidene fluoride (PVDF) by direct wet ball-milling and hot-pressing of the mixture of raw zinc powders and PVDF powders in alcohol. It is interesting that zinc spherical powders can be changed into 2-dimensional zinc flakes in the ball-milling and parallel oriented in the polymer under the following hot-pressing process. The composites are demonstrated to have significantly higher dielectric constants than those of bulk zinc/PVDF composites, with quite low dielectric loss and good thermal stability. A mechanism of parallel-board microcapacitor is proposed to explain the relationship of microstructure and dielectric properties.
- Published
- 2012
6. On extending Kohn-Sham density functionals to systems with fractional number of electrons
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Yang, Weitao [Department of Chemistry and Department of Physics, Duke University, Durham, North Carolina 27708, USA; Key Laboratory of Theoretical Chemistry of Environment, School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China]
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- 2017
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7. On the piecewise convex or concave nature of ground state energy as a function of fractional number of electrons for approximate density functionals
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Yang, Weitao [Department of Chemistry, Duke University, Durham, North Carolina 27708, USA, Key Laboratory of Theoretical Chemistry of Environment, School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China]
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- 2017
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8. High dielectric properties in a three-phase polymer composite induced by a parallel structure
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Jinbo Bai, Yuan Deng, Yao Wang, Ye Zhang, Mao Li, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, School of Chemistry and Environment, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China-School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, Laboratoire de mécanique des sols, structures et matériaux (MSSMat), CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and LIA 2MCSI
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Materials science ,Nanostructure ,Composite number ,02 engineering and technology ,Dielectric ,Aluminum flakes form a parallel structure in polymer matrix. ► The dielectric loss is largely lower after the addition of self-passivated AF. ► Parallel structure is helpful for composite to maintain a high dielectric constant ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Percolation ,Volume fraction ,General Materials Science ,Dielectric loss ,Nanorod ,Composite material ,[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics ,0210 nano-technology ,High-κ dielectric - Abstract
International audience; A novel three-phase composite, consisting of semiconductive bismuth sulfide (Bi2S3) nanorods and self-passivated aluminum flakes (AFs) embedded in a poly(vinylidene fluoride) (PVDF) matrix, was fabricated by simple but robust ball-milling and hot-pressing techniques. The dielectric properties of composites were studied before and after the addition of AFs as a function of Bi2S3 volume fraction and frequency. The Bi2S3 nanorods in PVDF matrix form a percolation path and increase the dielectric constant of the composite dramatically. And after adding the third phase AFs, a parallel structure forms during the hot-pressing progress. Parallel AFs in the PVDF matrix can largely reduce the leakage current due to the self-passivated insulating shell outside the AFs, thus an obvious reduction in the dielectric loss of the three-phase Bi2S3-AFs/PVDF composite is observed. Meanwhile, many microcapacitors formed with Al flakes as electrodes and Bi2S3/PVDF composite as the dielectric layer form, which makes an additional contribution to the high dielectric constant of the three-phase composite.
- Published
- 2013
9. Excellent dielectric properties of anisotropic polymer composites filled with parallel aligned zinc flakes
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Yanjingtian Guo, Jinbo Bai, Wencheng Bi, Yu Luo, Mao Li, Yuan Deng, Ye Zhang, Yao Wang, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, School of Chemistry and Environment, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China-School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, Laboratoire de mécanique des sols, structures et matériaux (MSSMat), and CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)
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Permittivity ,Materials science ,Physics and Astronomy (miscellaneous) ,Physics::Optics ,02 engineering and technology ,Dielectric ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Polyvinylidene fluoride ,0104 chemical sciences ,chemistry.chemical_compound ,Condensed Matter::Materials Science ,chemistry ,Equivalent circuit ,Composite material ,[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics ,0210 nano-technology ,Anisotropy ,RC circuit ,Electrical impedance - Abstract
International audience; Orderly polymer composites based on polyvinylidene fluoride assembled with parallel aligned zinc flakes were fabricated by a simple process. It is interesting to note that the microstructure of parallel arrangement could introduce excellent dielectric properties with obvious anisotropic dielectric behaviors. The dielectric constant in the parallel direction was obviously higher than that of the perpendicular direction. And the anisotropic intensity of interfacial polarization is proposed to interpret the anisotropic dielectric constant. Also, an equivalent circuit model of two parallel RC circuits in series, based on the analysis of impedance data, is employed to further discuss the anisotropic dielectric behavior.
- Published
- 2012
10. High dielectric constant and low loss in polymer composites filled by self-passivated zinc particles
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Mao Li, Yuan Deng, Yao Wang, Jinbo Bai, Ye Zhang, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, School of Chemistry and Environment, School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China-School of Chemistry and Environment, BeiHang University, Beijing 100191, PR China, Laboratoire de mécanique des sols, structures et matériaux (MSSMat), and CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)
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Materials science ,Composite number ,chemistry.chemical_element ,02 engineering and technology ,Zinc ,Dielectric ,010402 general chemistry ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,law ,General Materials Science ,Composite material ,[SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics ,High-κ dielectric ,Mechanical Engineering ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Polyvinylidene fluoride ,0104 chemical sciences ,Capacitor ,chemistry ,Mechanics of Materials ,Volume fraction ,Charge carrier ,0210 nano-technology - Abstract
Polyvinylidene fluoride (PVDF) composites filled by self-passivated zinc (Zn) particles were fabricated through a simple method of flocculation. The following measurement exhibits that the Zn/PVDF composite with filler volume fraction of 0.24 possesses the excellent dielectric properties, and the obtained dielectric constant and loss at 10 3 Hz were 52 and 0.05, respectively. It's considered that high dielectric constant is originated from the enhanced interfacial polarization, while the low loss is due mainly to the self-passivation layer of zinc carbonate hydroxide, which can serve as the insulating interface and reduce leakage current effectively through blocking the free transfer of charge carriers between adjacent Zn fillers. The developed polymer composites with favorable dielectric properties are potential for embedded capacitor applications.
- Published
- 2012
11. Gentlest ascent dynamics for calculating first excited state and exploring energy landscape of Kohn-Sham density functionals
- Author
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Yang, Weitao [Department of Chemistry, Duke University, Durham, North Carolina 27708, USA, Key Laboratory of Theoretical Chemistry of Environment, School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China]
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- 2015
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12. Enhancement of H{sub 2} evolution over new ZnIn{sub 2}S{sub 4}/RGO/MoS{sub 2} photocatalysts under visible light
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Fan, Yuzun [Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education, School of Chemistry and Environment, Beihang University, Beijing 100191 (China)]
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- 2015
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13. Effects of lipid concentration on anaerobic co-digestion of municipal biomass wastes
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Zhu, Tianle [School of Chemistry and Environment, Beihang University, Beijing 100191 (China)]
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- 2014
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14. Investigation on transition behavior and electrical properties of (K{sub 0.5}Na{sub 0.5}){sub 1-x}Li{sub x}Nb{sub 0.84}Ta{sub 0.1}Sb{sub 0.06}O{sub 3} around polymorphic phase transition region
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Liu, Yang [School of Chemistry and Environment Engineering, Shaoguan University, Shaoguan 512005 (China)]
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- 2014
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15. Applications of Cu{sub 2}O octahedral particles on ITO glass in photocatalytic degradation of dye pollutants under a halogen tungsten lamp
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Li, Weishan [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)]
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- 2013
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16. Morphology-controlled electrodeposition of Cu{sub 2}O microcrystalline particle films for application in photocatalysis under sunlight
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Li, Weishan [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)]
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- 2012
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17. C-H...Cl relevant discrepancy on structure, magnetic and electronic conductivity of two mixed-valence Cu{sup I}Cu{sup II} coordination polymers
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Ying, Yu [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)]
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- 2011
18. Photochemical preparation of CdS hollow microspheres at room temperature and their use in visible-light photocatalysis
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Zihe, Zhang [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)]
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- 2011
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19. A high ON/OFF ratio organic film for photo- and electro-dual-mode recording
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Qinglin, Yang [School of Chemistry and Environment, Beijing University of Aeronautics and Astronautics, Beijing 100083 (China)]
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- 2009
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20. Measurement of metal bioaccessibility in vegetables to improve human exposure assessments: field study of soil-plant-atmosphere transfers in urban areas, South China
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Yuan Kang, Georges Bertoni, Ning Li, Tiantian Xiong, Muhammad Shahid, Christophe Laplanche, Camille Dumat, Antoine Pierart, École nationale supérieure agronomique de Toulouse [ENSAT], Laboratoire Ecologie Fonctionnelle et Environnement (ECOLAB), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut Ecologie et Environnement (INEE), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Dynamiques Forestières dans l'Espace Rural (DYNAFOR), Institut National de la Recherche Agronomique (INRA)-École nationale supérieure agronomique de Toulouse [ENSAT]-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Centre d'Etude et de Recherche Travail Organisation Pouvoir (CERTOP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse - Jean Jaurès (UT2J), Department of Environmental Sciences, COMSATS Institute of information Technology, South China University of Technology [Guangzhou] (SCUT), School of Chemistry and Environment, South China Normal University, Dynamiques et écologie des paysages agriforestiers (DYNAFOR), École nationale supérieure agronomique de Toulouse [ENSAT]-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
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[SDV]Life Sciences [q-bio] ,urban areas ,0211 other engineering and technologies ,Environmental pollution ,02 engineering and technology ,Incineration ,settled particulate matter ,010501 environmental sciences ,01 natural sciences ,[SHS]Humanities and Social Sciences ,Soil ,11. Sustainability ,Vegetables ,Soil Pollutants ,General Environmental Science ,Water Science and Technology ,media_common ,Vehicle Emissions ,2. Zero hunger ,Agriculture ,General Medicine ,Particulates ,6. Clean water ,bioaccessibility ,Environmental chemistry ,visual_art ,visual_art.visual_art_medium ,Environmental Monitoring ,Pollution ,China ,Environmental Engineering ,roads ,media_common.quotation_subject ,Biological Availability ,metals ,Food Contamination ,human exposure ,Risk Assessment ,Metal ,Atmosphere ,Geochemistry and Petrology ,Metals, Heavy ,Environmental Chemistry ,Urban agriculture ,waste incinerator ,Environmental quality ,0105 earth and related environmental sciences ,021110 strategic, defence & security studies ,Environmental engineering ,vegetable quality ,15. Life on land ,Plant Leaves ,13. Climate action ,Environmental science ,Particulate Matter - Abstract
International audience; The quality of cultivated consumed vegetables in relation to environmental pollution is a crucial issue for urban and peri-urban areas, which host the majority of people at the global scale. In order to evaluate the fate of metals in urban soil-plant-atmosphere systems and their consequences on human exposure, a field study was conducted at two different sites near a waste incinerator (site A) and a highway (site B). Metal concentrations were measured in the soil, settled atmospheric particulate matter (PM) and vegetables. A risk assessment was performed using both total and bioaccessible metal concentrations in vegetables. Total metal concentrations in PM were (mg kg(-1)): (site A) 417 Cr, 354 Cu, 931 Zn, 6.3 Cd and 168 Pb; (site B) 145 Cr, 444 Cu, 3289 Zn, 2.9 Cd and 396 Pb. Several total soil Cd and Pb concentrations exceeded China's Environmental Quality Standards. At both sites, there was significant metal enrichment from the atmosphere to the leafy vegetables (correlation between Pb concentrations in PM and leaves: r = 0.52, p
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- 2016
21. Crystallographic Analysis and Solar Cells of Polysilicon Films Formed by Aluminium Induced Crystallization
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Tüzün, Ö., Qiu, Y., Chatterjee, S., Venkatachalam, Srisaran, Maurice, C., Slaoui, A., Gordon, I., Beaucarne, G., Poortmans, J., Institut d'Electronique du Solide et des Systèmes (InESS), Centre National de la Recherche Scientifique (CNRS), School of chemistry and environment, South China Normal University CUANGZHOU, Centre Science des Matériaux et des Structures (SMS-ENSMSE), École des Mines de Saint-Étienne (Mines Saint-Étienne MSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Département Microstructures et Traitements Thermomécaniques (MTT-ENSMSE), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-SMS, WIP-Renewable Energies, and Jung, Marie-Anne
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Thin Films Solar Cells ,Thin Film Crystalline Silicon Solar Cells and Wafer Equivalents ,ComputingMilieux_MISCELLANEOUS - Abstract
24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 2544-2548, In this work, we compare structural and electrical properties of poly-Si solar cells formed on alumina and glass-ceramic substrates. The formation of poly-Si seed layers formed by aluminium induced crystallization (AIC) technique is followed by the epitaxial thickening, using low pressure chemical vapor deposition (LPCVD). Intrinsic and n+ type amorphous silicon, respectively, were deposited on p-type epi-layer to form the heterojunction emitter based solar cells. The surface morphologies of the AIC seed layer and epi-layer were observed by optical microscope and electron backscattering diffraction (EBSD) techniques. The average grain size of AIC poly-Si layers increases up to 25.2Fm by using glass-ceramic substrate while it is only 7.6Fm for poly-Si films on alumina substrates. Furthermore the preferred orientation is in both cases. Finally, the characteristics of poly-Si based solar cells were measured by using a solar simulator. The best devices show an efficiency of 3.3% for cells on glassceramic substrates and about 2.9% on alumina substrates. The reason for this difference will be discussed.
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- 2009
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22. Four Three-dimensionnal Lanthanide Coordination Polymers Constructed from Benzene-1,4-dioxyacetic acid
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Yongcai Qiu, Nicolas Kerbellec, Jian-Qiang Liu, Carole Daiguebonne, Rong-Hua Zeng, Olivier Guillou, Hong Deng, School of Chemistry and Environment, South China Normal University, Sciences Chimiques de Rennes / Matériaux Inorganiques: Chimie Douce et Réactivité (MICDR), Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES), Department of Chemistry, Laboratory of Physico-Inorganic Chemistry, School of Chemistry & EnVironment and Key Laboratory of Electrochemical Technology on Energy Storage and Power Generation in Guangdong UniVersities, Key Lab of Electrochemical Technology on Energy Storage and Power Generation in Guangdong Universities, Guangzhou 510631, PR China, Guangdong Universities, Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Centre National de la Recherche Scientifique (CNRS)
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Lanthanide ,010405 organic chemistry ,Coordination polymer ,Triclinic crystal system ,[CHIM.INOR]Chemical Sciences/Inorganic chemistry ,010402 general chemistry ,01 natural sciences ,Hydrothermal circulation ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,chemistry ,Materials Chemistry ,Metal-organic framework ,Physical and Theoretical Chemistry ,Isostructural ,Benzene ,Monoclinic crystal system - Abstract
Four crystalline lanthanide(III) three-dimensional (3D) coordination polymers {[La(BDOA) 1.5 (H 2 O)] · H 2 O} n ( 1 ), {[Nd(BDOA) 1.5 (H 2 O)] · H 2 O} n ( 2 ), [Tm(BDOA) 1.5 (H 2 O)] n ( 3 ), [Yb(BDOA) 1.5 (H 2 O)] n ( 4 ) were obtained under hydrothermal conditions and characterized by elemental analysis, IR, as well as single-crystal X-ray diffraction. Compounds 1 and 2 crystallize in the monoclinic system, space group P 2 1 / c , they are isostructural and exhibit the same 3 21 .4 57 .5 13 topological network constructed from different coordination modes of two BDOA ligands, whereas isostructural 3 and 4 crystallizes in the triclinic system, space group P 1 ¯ , it holds 3 9 .4 20 .5 7 topological architecture based on another two different coordination modes BDOA ligands. Moreover, a computational method is applied to evaluate the potential porosity of complex 1 .
- Published
- 2007
23. Raman spectroscopic quantification of graphene oxide in soil: Transport, surficial enrichment and environmental effects.
- Author
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Chen Q, Huang H, Li X, Pan L, Chen Y, Zhong Q, Wu X, and Yang ST
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- Graphite chemistry, Soil chemistry, Soil Pollutants analysis, Spectrum Analysis, Raman methods
- Abstract
The transport and retention data in environmental media are indispensable for the hazard evaluations of graphene materials. Due to the complexity of soil, the transport of graphene is hard to quantify without isotope labeling. Herein, we developed 2D Raman mapping as a label-free technique to quantify graphene oxide (GO) in soil. After pre-treatment by hydrazine hydrate to quench its fluorescence, the quantification of GO in soil was achieved in the range of 0.1-1000 mg/L by measuring the average G-band intensity. In column transport experiment, the transport and retention of GO in soil depended on the solution chemistry. Lower pH and higher ionic strength hindered the transport of GO. In particular, Ca
2+ showed the most obvious retardation on the transport of GO. GO enriched in the surficial soil layer by several folds of the initial concentrations, and higher GO concentration led to more surficial enrichment. The sowing manner of seeds affected the soil enrichment of GO, too. The surficial enrichment of GO reduced its direct contact with seedling roots, resulting in the alleviation of GO toxicity. Our results provided a facile method to study the environmental behaviors of graphene and highlighted the crucial impacts of environmental media on the graphene toxicity., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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24. Realizing Stable Luminescence in Antimony Doped Hybrid Tin(IV) Chloride toward Full Spectrum WLED and Anticounterfeiting Applications.
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Ma H, Yang E, Tan F, Zhou Q, Yang T, Tang H, Wan J, Jiang L, and Wang Z
- Abstract
The outstanding optical properties empower Sb
3+ -doped zero-dimensional hybrid metal halides as cutting-edge luminescent materials. In this research, we present an efficient hybrid tin chloride, TEA2 SnCl6 :Sb3+ (TEA = tetraethylammonium), with broad dual emission bands peaking in the blue and orange regions that arise from the singlet and triplet state emissions of [SbCl5 ]2- , respectively. TEA2 SnCl6 :Sb3+ demonstrates a high photoluminescence quantum yield (PLQY) of 83.5% under 328 nm excitation, while 358 nm light induces an orange emission with a PLQY of 92.5% and a low thermal quenching behavior (73.9% at 423 K). Benefiting from the appealing luminescence properties of TEA2 SnCl6 :Sb3+ , a full spectrum white light-emitting diode (WLED) device and an anticounterfeiting model were constructed, affirming the potential use of Sb3+ -doped TEA2 SnCl6 hybrid metal halide in versatile application fields.- Published
- 2024
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25. Synthesis and characterization of etherified cationic starch flocculant derived from Manihot esculenta peel with varying degrees of substitution.
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Rahmat S, Othman N, Asharuddin SM, Ahmad SN, Din MFM, and Sarani NA
- Abstract
Cationic Manihot esculenta (ME) peel starch was synthesized through etherification method using 3-chloro-2-hydroxypropyl trimethylammonium chloride (CHPTAC) as cationizing monomer. The optimization of the main factors influencing the degree of substitution (DS) was conducted using central composite design (CCD) and response surface methodology (RSM). The factors assessed include CHPTAC concentration, catalyst sodium hydroxide (NaOH) concentration, and reaction time. The DS values of the cationic starches were obtained between 0.39 and 0.99. The maximum DS value was up to 0.99 at 0.615 mol/L of CHPTAC, 30 % (w/v) NaOH, and a reaction time of 5 h. The finding based on the optimization using RSM reflected that CHPTAC and NaOH concentrations are the key variables determining the DS value, while reaction time has a negligible impact on the etherification process. Furthermore, the chemical composition, morphology, and structure of the cationic ME peel starch were characterized by scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDX), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD) and nuclear magnetic resonance spectroscopy (
1 H NMR). It was confirmed that the modifying monomers penetrated the surface layer of the starch granules and attached to the starch backbone., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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26. Asymmetric Transfer Hydrogenation of Ketones Improved by PNN-Manganese Complexes.
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Su Y, Ma Z, Wang J, Li L, Yan X, Ma N, Liu Q, Solan GA, and Wang Z
- Abstract
Chiral manganese(I) complexes that contain carbocyclic-fused 8-amino-5,6,7,8-tetrahydroquinolinyl groups that are appended with distinct para -R substituents have proven to be effective catalysts in the asymmetric transfer hydrogenation (ATH) of a wide range of ketones (48 examples). Notably, Mn2 proved to be the most productive catalyst, allowing an outstanding turnover number of 8300 with catalyst loadings as low as 0.01 mol %. Furthermore, this catalytic protocol shows considerable promise for applications in the synthesis of chiral drugs such as Lusutrombopag.
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- 2024
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27. Simultaneous determination of bisphenol A and bisphenol AF using a carbon nanocages and CuO nanochains-based sensitive voltammetric sensor.
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Chang F, Chen J, Tan J, Pu Z, and Wang D
- Abstract
A new and highly sensitive voltammetric technique was described in this study for the concurrent detection of endocrine disruptors bisphenol A (BPA) and bisphenol AF (BPAF) based on carbon nanocages (CNCs) and copper oxide nanochains (CuONCs). The CNCs was prepared by the solvothermal method and characterized using various techniques. Utilizing the nanocomposite of CNCs and CuONCs, the voltammetric sensor demonstrated outstanding performance in detecting BPA and BPAF simultaneously with distinct oxidation peaks and increased current peaks. The voltammetric signals have linear relationships with the two bisphenols ranging from 0.500 μM to 100 μM with a detection limit of 0.16 µM for BPA and 0.14 µM for BPAF. The newly designed sensor showed reliable consistency, long-term durability and anti-interference ability, and performed well in analyzing real water samples, indicating great potential for environmental monitoring., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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28. Sensitive and selective detection of tetracycline using fluorescence-enhanced Eu(III)-functionalized silver nanoparticles with homocysteine.
- Author
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Xie H, Li S, Zhang Y, Xi S, Zheng H, Wang H, Li Y, and Wei T
- Abstract
Utilizing metal luminescence enhancement to design fluorescent probes is a very sensible strategy. Herein, a fluorescent probe based on europium (III)-functionalized silver nanoparticles-conjugated homocysteine (AgNPs-Hcy-Eu
3+ ) was proposed for the selective and sensitive detection of tetracycline (TC). In this probe, Eu(III) was employed as the detection signal unit for TC, while AgNPs-Hcy was used as the ligand of fluorescence enhancement. When TC exists, it can bind to Eu3+ immobilized in AgNPs-Hcy, leading to an enhanced fluorescence signal from Eu3+ through energy transfer. Under optimal conditions, the fluorescence intensity of AgNPs-Hcy-Eu3+ increased linearly with increasing TC concentration in the range of 0.1-30 μM (R2 = 0.9964). The fluorescent probe own fluorescence enhancement, paving the way for sensitive detection with a low detection limit of 0.083 μM. It also has good selectivity for common antibiotics and anions. This work can be applied to the determination of TC in tap water and milk with recoveries of 94-98.5%. We expect AgNPs-Hcy-Eu3+ to have potential applications in environmental testing and food safety., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)- Published
- 2024
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29. Isomeric Dimer Acceptors for Stable Organic Solar Cells with over 19% Efficiency.
- Author
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Li Y, Ge Z, Mei L, Ma H, Chen Y, Wang X, Yu J, Lu G, Yang R, Chen XK, Yin S, and Sun Y
- Abstract
The strategy of isomerization is known for its simple yet effective role in optimizing molecular configuration and enhancing the power conversion efficiency (PCE) of organic solar cells (OSCs). However, the impact of isomerization on the design of dimer acceptors has been rarely investigated, and the relationship between the chemical structure and optoelectronic property remains unclear. In this study, we designed and synthesized two dimer acceptor isomers named D-TPh and D-TN, which differ in the positional arrangement of their end capping groups. Compared to D-TN, D-TPh exhibited enhanced backbone planarity, elevated lowest unoccupied molecular orbital energy level, and more ordered molecular stacking. Consequently, the OSC device based on PM6:D-TPh achieved a PCE of 19.05%, higher than that (PCE = 18.42%) of the device based on PM6:D-TN. Large-area PM6:D-TPh devices (1 cm²) yielded a PCE of 18.0%. More importantly, the extrapolated T80 lifetime of the PM6:D-TPh device is over 2800 h with MPP tracking under continuous one-sun illumination. These results suggest that isomerization strategy is an effective way to optimize the molecular configuration of dimer acceptors for the fabrication of high-efficiency and stable OSCs., (© 2024 Wiley‐VCH GmbH.)
- Published
- 2024
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30. Spatial confinement Fenton oxidation realized via tunable nanopore structure of porous carbon.
- Author
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Zhou C, Sun M, Zhang P, Yuan Y, Peng J, Zhang H, He C, Yao G, Liu Y, Zhou P, and Lai B
- Abstract
Spatially confined structure exhibits surprising physics and chemistry properties that significantly impact the thermodynamics and kinetics of oxidation reactions. Herein, porous carbons are rationally designed for tunable nanopore structures (micropores, 4.12 % ∼ 91.64 %) and diverse spatial confinement ability, as indicated by their differential enhancement performances in the Fenton oxidation. Porous carbons can alter the characteristics of the charge transport process for accelerating sustainable electron shuttle between hydrogen peroxide and iron species, and thus exhibit long-term performance (17 cycling tests). The positive spatial confinement for boosting Fenton oxidation (charge transport, mass transfer) occurs in nanochannels < 1 nm, while the diminished effect ranges of 1-1.5 nm, and the adverse effect ranges greater than 1.5 nm. The density functional theory calculation provides further support for certifying the promoted charge transport process and spatial confinement for hydroxyl radical inside the confined nanochannel structure (below 1 nm, especially) by the comparatively large electron cloud and the relatively negative adsorption energy, respectively. Coupling nanochannels with the Fenton oxidation greatly utilize hydrogen peroxide, due to spatial nanoconfinement and selective adsorption towards target contaminants. This strategy of deploying nanochannels in catalyst design can be applied for the elaborate construction of efficient nanostructured catalysts for environmental remediation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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31. 3D Covalent Organic Frameworks with 16-Connectivity for Photocatalytic C(sp 3 )-C(sp 2 ) Cross-Coupling.
- Author
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Lu M, Zhang SB, Li RH, Dong LZ, Yang MY, Huang P, Liu YF, Li ZH, Zhang H, Zhang M, Li SL, and Lan YQ
- Abstract
The connectivity (valency) of building blocks for constructing 3D covalent organic frameworks (COFs) has long been limited to 4, 6, 8, and 12. Developing a higher connectivity remains a great challenge in the field of COF structural design. Herein, this work reports a hierarchical expansion strategy for making 16-connected building blocks to construct 3D COFs with sqc topology. The [16 + 2] construction achieved by condensation between a 16-connected carbazolyl dicyanobenzene-based building block (CzTPN) and linear diamino linkers (BD or Bpy) affords two 3D COFs (named CzBD COF and CzBpy COF). Furthermore, attributed to the well-organized donor-acceptor (D-A) heterojunction, the Ni chelated CzBpy COF (Ni@CzBpy COF) exhibits excellent performance for photoredox/Ni dual catalytic C(sp
3 )-C(sp2 ) cross-coupling of alkyltrifluoroborates with aryl halides, achieving a maximum 98% conversion and 94% yield for various substrates. This work developed the first case of high-connectivity COFs bearing 16-connected units, which is the highest connectivity reported until now, and achieved efficient photocatalysis applications, thus greatly enriching the possibilities of COFs.- Published
- 2024
- Full Text
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32. Developing Covalent Organic Framework Biocatalysts through Enzyme Encapsulation.
- Author
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Gao R, Kou X, Huang S, Chen G, and Ouyang G
- Subjects
- Porosity, Enzymes metabolism, Enzymes chemistry, Metal-Organic Frameworks chemistry, Metal-Organic Frameworks metabolism, Biocatalysis, Enzymes, Immobilized chemistry, Enzymes, Immobilized metabolism
- Abstract
Utilizing covalent organic frameworks (COFs) as porous supports to encapsulate enzyme represents an advanced strategy for constructing COFs biocatalysts, which has inspired numerous interests across various applications. As the structural advantages including ultrastable covalent-bonded linkage, tailorable pore structure, and metal-free biocompatibility, the resultant enzyme-COFs biocatalysts showcase functional enhancement in catalytic activity, chemical stability, long-term durability, and recyclability. This Concept describes the recent advances in the methodological strategies for engineering the COFs biocatalysts, with specific emphasis on the pore entrapment and in situ encapsulation strategies. The structural advantages of the COFs hybrid biocatalysts for organic synthesis, environment- and energy-associated applications are also canvassed. Additionally, the remaining challenges and the forward-looking directions in this field are also discussed. We believe that this Concept can offer useful methodological guidance for developing active and robust COFs biocatalysts., (© 2024 Wiley-VCH GmbH.)
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- 2024
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33. Toxicity and decomposition activity inhibition of VO 2 micro/nanoparticles to white rot fungus Phanerochaete chrysosporium.
- Author
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Zhang Q, Yuan Y, Hu Y, Lu RL, Wang X, Zhong Q, Wu X, Wang H, and Yang ST
- Abstract
Vanadium dioxide (VO
2 ) is an excellent phase transition material widely used in various applications, and thus inevitably enters the environment via different routes and encounters various organisms. Nonetheless, limited information is available on the environmental hazards of VO2 . In this study, we investigated the impact of two commercial VO2 particles, nanosized S-VO2 and micro-sized M-VO2 on the white rot fungus Phanerochaete chrysosporium. The growth of P. chrysosporium is significantly affected by VO2 particles, with S-VO2 displaying a higher inhibitory effect on weight gain. In addition, VO2 at high concentrations inhibits the formation of fungal fibrous hyphae and disrupts the integrity of fungus cells as evidenced by the cell membrane damage and the loss of cytoplasm. Notably, at 200 μg/mL, S-VO2 completely alters the morphology of P. chrysosporium, while the M-VO2 treatment does not affect the mycelium formation of P. chrysosporium. Additionally, VO2 particles inhibit the laccase activity secreted by P. chrysosporium, and thus prevent the dye decoloration and sawdust decomposition by P. chrysosporium. The mechanism underlying this toxicity is related to the dissolution of VO2 and the oxidative stress induced by VO2 . Overall, our findings suggest that VO2 nanoparticles pose significant environmental hazards and risks to white rot fungi., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
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34. Brønsted Acid Triggers [6/7 + 1] Cascade Cyclization by N -Alkyl Amine C(sp 3 )-N Cleavage: Mild Synthesis of Benzo[1,4]oxazepane and Dihydrobenzo[1,5]oxazocine.
- Author
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Yin L, Zhang Z, Huang S, Wang Z, and Huang C
- Abstract
A catalyst-free mild synthesis was reported to produce medium-ring oxazepane and oxazocine derivatives from aminomaleimides and N -alkyl amines. The substrate and acidic additives were employed to cleave the C(sp
3 )-N bond as a one-carbon synthon for C-C and C-O coupling, thus facilitating the [ n + 1] cascade cyclization reaction, which enabled the construction of seven- and eight-membered N , O -heterocycles at room temperature. The method exhibits abroad substrate scope and remarkable tolerance toward various functional groups (seven-membered 28 examples, eight-membered 8 examples, and activated N -alkyl amine 12 examples) and utilization of natural products (2 examples).- Published
- 2024
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35. Water residence time controls seasonal nitrous oxide budget in a semi-enclosed bay: Insights from an improvement estimation method.
- Author
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Cai S, Lao Q, Cai M, Silva DPTT, Lu X, Zhou X, Jin G, Chen C, and Chen F
- Subjects
- China, Water Pollutants, Chemical analysis, Seawater chemistry, Bays, Nitrous Oxide analysis, Seasons, Environmental Monitoring
- Abstract
This study developed an estimation method for the N
2 O budget using15 N stable isotope labeling techniques, a dual-layer model and a box model, which was used to elucidate the underlying dynamics of N2 O accumulation in Zhanjiang Bay. The results showed that although the net input of N2 O during the rainy season was 2.36 times higher than that during the dry season, the overall N2 O concentration was only 66.6 % of that during the dry season due to the extended water residence time in the dry season. Our findings highlighted that water residence time was the key factor for the N2 O emission, and a longer water residence time was unfavorable for the efflux of N2 O through hydrodynamic processes and was more conducive to the production and accumulation of N2 O within the bay. This research enhanced our comprehension of N2 O dynamics and provided crucial insights for refining nitrogen management strategies and mitigation efforts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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36. Rapid analysis of Bacillus cereus spore biomarkers based on porous channel cuttlebone SERS substrate.
- Author
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Lai Y, Jiang G, Liang T, Huang X, Jiang W, Xu W, Sun R, Dai Z, and Li C
- Subjects
- Porosity, Metal Nanoparticles chemistry, Picolinic Acids analysis, Picolinic Acids chemistry, Limit of Detection, Surface Properties, Bacillus cereus isolation & purification, Bacillus cereus metabolism, Spectrum Analysis, Raman methods, Spores, Bacterial isolation & purification, Spores, Bacterial chemistry, Silver chemistry, Biomarkers analysis
- Abstract
Background: Bacillus cereus (B. cereus) is a widespread conditional pathogen that affects food safety and human health. Conventional methods such as bacteria culture and polymerase chain reaction (PCR) are difficult to use for rapid identification of bacterial spores because of the relatively long analysis times. From a human health perspective, there is an urgent need to develop an ultrasensitive, rapid, and accurate method for the detection of B. cereus spores., Results: The study proposed a new method for rapidly and sensitively detecting the biomarkers of bacterial spores via surface-enhanced Raman spectroscopy (SERS) combined with electrochemical enrichment. The 2,6-Pyridinedicarboxylic acid (DPA) was used as the model analyte to acts as a biomarker of B. cereus spores. The SERS substrate was developed via the in-situ generation of Ag nanoparticles (AgNPs) in a cuttlebone-derived organic matrix (CDOM). Because of the depletion of chitin reduction sites on the CDOM, the pores of the porous channels expanded. The pores diameter of the AgNPs/CDOM porous channel was found to be in the range of 0.7-1.3 nm through molecular diffusion experiments. Based on the porosity of AgNPs/CDOM substrates and the high sensitivity of SERS substrates, the sensor can rapidly and accurately electronically enrich DPA in 40 s with the limit of detection (LOD) of 0.3 nM., Significance: The results demonstrate that electrochemically assisted SERS substrates can be served as a high sensitivity electrochemical-enrichment device for the rapid and sensitive detection of bacterial spores with minimal interference from potentially coexisting species in biological samples. In this study, it opens up a platform to explore the application of porous channels in natural bio-derived materials in the field of food safety., Competing Interests: Declaration of competing interest We wish to confirm that there are no known conflicts of interest associated with this publication and declare that we have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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37. Exploring naphthoquinone and anthraquinone derivatives as antibiotic adjuvants against Staphylococcus aureus biofilms: Synergistic effects of menadione.
- Author
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Chan YL, Tang SN, Osman CP, Chee CF, and Tay ST
- Abstract
Given the ability of Staphylococcus aureus to form biofilms and produce persister cells, making infections difficult to treat with antibiotics alone, there is a pressing need for an effective antibiotic adjuvant to address this public health threat. In this study, a series of quinone derivatives were evaluated for their antimicrobial and antibiofilm activities against methicillin-susceptible and methicillin-resistant S. aureus reference strains. Following analyses using broth microdilution, growth curve analysis, checkerboard assay, time-kill experiments, and confocal laser scanning microscopy, menadione was identified as a hit compound. Menadione exhibited a notable antibacterial profile (minimum inhibitory concentration, MIC = 4-16 μg/ml; minimum bactericidal concentration, MBC = 256 μg/ml) against planktonic S. aureus and its biofilms (minimum biofilm inhibitory concentration, MBIC
50 = 0.0625-0.25 μg/ml). When combined with oxacillin, erythromycin, and vancomycin, menadione exhibited a synergistic or additive effect against planktonic cells and biofilms of two S. aureus reference strains and six clinical isolates, highlighting its potential as a suitable adjuvant for further development against S. aureus biofilm-associated infections., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Sun Tee Tay reports financial support, administrative support, equipment, drugs, or supplies, and statistical analysis were provided by Universiti Malaya. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
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38. Fe-N x sites coupled with Fe 3 C on porous carbon from plastic wastes for oxygen reduction reaction.
- Author
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Jiang X, Zhang R, Liao Q, Zhang H, Yang Y, and Zhang F
- Abstract
Isolated Fe-N
x sites coupled with Fe3 C nanoparticles co-embedded in N-doped porous carbon were fabricated using polyethylene terephthalate wastes as carbon sources. Benefiting from the synergistic effect between Fe-Nx sites and Fe3 C, and the hierarchical porous structure, the catalyst exhibits outstanding ORR performance, realizing the concept of turning trash into treasure.- Published
- 2024
- Full Text
- View/download PDF
39. Mechanism study of Dual-Emission ratiometric fluorescent pH-Sensitive carbon quantum dots and its application on mornitoring enzymatic catalysis.
- Author
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Xue Z, Ning, Jia K, Liu H, Xiang Y, Cao J, Chen J, Zhong Y, Wang X, and Zhang Z
- Abstract
Carbon dots (CQD) have received significant attention as a novel ratiometric fluorescent pH nanoprobe, owing to their favorable optical properties and excellent biocompatibility. Despite their appealing features, the precise mechanism behind the pH-sensitive photoluminescence of CQDs remains to be fully understood. This study endeavors to unravel the mechanism underlying the pH-responsive ratiometric fluorescence in dual-emission CQDs, synthesized through a one-step hydrothermal method using o-phenylenediamine and oxalic acid as precursors. The resultant CQDs exhibit inherent dual-emission at wavelengths of 383 nm and 566 nm, with the ratiometric fluorescence response tailored by the ratio of precursors, providing a robust tool for pH sensing across a range of 2 to 6. Detailed characterizations, including chemical, morphological, and optical analyses, alongside theoretical insights from time-dependent density functional theory (TD-DFT), elucidate the mechanism underlying the pH-dependent luminescence, attributed to the electron cloud transmission between amide and adjacent carboxyl groups on the CQD surface. The superior performance of these CQDs in real-time pH monitoring is demonstrated through their application in glucose oxidase-catalyzed reactions, showcasing their potential as efficient, reliable nanoprobes for biomedical research and diagnostic applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
40. Regulating Electron-Phonon Coupling by Solid Additive for Efficient Organic Solar Cells.
- Author
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Ge Z, Qiao J, Li Y, Song J, Duan X, Fu Z, Hu H, Yang R, Yin H, Hao X, and Sun Y
- Abstract
Strong electron-phonon coupling can hinder exciton transport and induce undesirable non-radiative recombination, resulting in a shortened exciton diffusion distance and constrained exciton dissociation in organic solar cells (OSCs). Therefore, suppressing electron-phonon coupling is crucially important for achieve high-performance OSCs. Here, we employ the solid additive to regulating electron-phonon coupling in OSCs. The planar configuration of SA1 confers a significant advantage in suppressing lattice vibrations in the active layers, reducing the scattering of excitons by phonons caused by lattice vibrations. Consequently, a slow but sustained hole transfer process is identified in the SA1-assisted film, indicating an enhancement in hole transfer efficiency. Prolonged exciton diffusion length and exciton lifetime are achieved in the blend film processed with SA1, attributed to a low non-radiative recombination rate and low energetic disorder for charge carrier transport. As a result, a high efficiency of 20% was achieved for ternary device with a remarkable short-circuit current. This work highlights the important role of suppressing electron-phonon coupling in improving the photovoltaic performance of OSCs., (© 2024 Wiley‐VCH GmbH.)
- Published
- 2024
- Full Text
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41. Long-lasting anti-corrosion direct-to-metal polyurethane NP-GLIDE coatings based on the coordination effect and dual cross-linking of polyphenol.
- Author
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Chen B, Zhou C, Xiong W, Peng J, Luo X, Pan X, and Liu Y
- Abstract
Aluminum and its alloys have been widely used in our lives. However, Aluminum and its alloys is prone to corrosion, especially in harsh environment. In recent years, hydrophobic coatings were used in the corrosion protection of metal. But, the low surface tension of resins made them have a worse wettability on metal which had high surface tension, resulting in a worse adhesion of these coatings. Herein, we developed a long-lasting anti-corrosion direct-to-metal polyurethane NP-Glide coating based on the coordination effect of polyphenol and dual cross-linking. In comparative evaluation, the corrosion protection and anti-contamination performances of direct-to-metal polyurethane NP-Glide coating are significantly improved by the introduction of functional monomer dopamine methacrylamide (DMA) and TEMAc-8. The PU coatings with 10 wt% TEMAc-8 possesses high impedance value (|Z|
0.01Hz > 109 Ω•cm2 ) after 40 days of immersion in 3.5 wt% NaCl solution, exhibiting a great pull-off adhesion both in dry and wet coating, and a long-term anti-corrosion performance for aluminum alloy protection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)- Published
- 2024
- Full Text
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42. A novel iron oxide (Fe 3 O 4 )-laden titanium carbide (Ti 3 C 2 ) MXene stacks for the efficient removal of tetracycline from aqueous solution.
- Author
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Hu X, Li G, Zhang Y, Lu M, Pu W, Dai Y, Yang M, and Wang H
- Abstract
Fe
3 O4 has the advantages of unique magnetic stability and low biological toxicity, which can improve pollutants separation efficiency. MXenes are two-dimensional materials and easy surface functionalization that can provide suitable carriers for Fe3 O4 . In this work, we synthesized magnetic MXene composites by a one-pot method that relies on doping Fe3 O4 particles onto Ti3 C2 MXene nanosheets by heat treatment. The Fe3 O4 /Ti3 C2 MXene was analyzed by SEM, XRD, FTIR and XPS techniques, which showed that the material has good tetracycline (TC) removal properties and magnetic separation ability. The results showed that the adsorption capacity of it was 46.42 mg g-1 , and the removal efficiency of 0.06 g adsorbent for 50 mL of 30 mg L-1 TC could reach 92.1% in a wide pH range of 4-10, when the adsorption temperature was 25 °C, and the adsorption time was 3 h. The adsorption data were consistent with Langmuir and the proposed second-order kinetic model, and the thermodynamic experiments confirmed that the adsorption of TC was a monolayer physicochemical adsorption coexisting heat-trapping process (ΔH = 15.72 kJ mol-1 ). In addition, the adsorption of TC by Fe3 O4 /Ti3 C2 MXene was attributed to the synergistic effect of electrostatic attraction, hydrogen bonding and π-π packing. In conclusion, the saturation magnetization of Fe3 O4 /Ti3 C2 MXene is 27.3 emu/g and it can not only be separated from water using its strong magnetic properties to avoid secondary contamination, but also can be used as a promising material to effectively remove antibiotics from aqueous media., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)- Published
- 2024
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43. Development Status of Solar-Driven Interfacial Steam Generation Support Layer Based on Polymers and Biomaterials: A Review.
- Author
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Yan H, Wang P, Li L, Zhao Z, Xiang Y, Guo H, Yang B, Yang X, Li K, Li Y, He X, and You Y
- Abstract
With the increasing shortage of water resources and the aggravation of water pollution, solar-driven interfacial steam generation (SISG) technology has garnered considerable attention because of its low energy consumption, simple operation, and environmental friendliness. The popular multi-layer SISG evaporator is composed of two basic structures: a photothermal layer and a support layer. Herein, the support layer underlies the photothermal layer and carries out thermal management, supports the photothermal layer, and transports water to the evaporation interface to improve the stability of the evaporator. While most research focuses on the photothermal layer, the support layer is typically viewed as a supporting object for the photothermal layer. This review focuses on the support layer, which is relatively neglected in evaporator development. It summarizes existing progress in the field of multi-layer interface evaporators, based on various polymers and biomaterials, along with their advantages and disadvantages. Specifically, mainly polymer-based support layers are reviewed, including polymer foams, gels, and their corresponding functional materials, while biomaterial support layers, including natural plants, carbonized biomaterials, and other innovation biomaterials are not. Additionally, the corresponding structure design strategies for the support layer were also involved. It was found that the selection and optimal design of the substrate also played an important role in the efficient operation of the whole steam generation system. Their evolution and refinement are vital for advancing the sustainability and effectiveness of interfacial evaporation technology. The corresponding potential future research direction and application prospects of support layer materials are carefully presented to enable effective responses to global water challenges.
- Published
- 2024
- Full Text
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44. A fluorimetric and colorimetric dual-mode sensor based on N, S co-doped carbon dots functionalized silver nanoparticles for glucose detection.
- Author
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Fang S, Li S, Yin P, Yao G, Yu H, He Y, Li X, Yang M, and Tan W
- Abstract
A fluorescent-colorimetric dual-signal platform, N, S co-doped carbon dots functionalized silver nanoparticles (NS-CDs-AgNPs), was designed in situ by reducing AgNO
3 in the presence of N, S co-doped carbon dots (NS-CDs) under the assistance of microwave irradiation for glucose determination. With the formation of silver nanoparticles (AgNPs), the intrinsic fluorescence of NS-CDs was quenched, showing the fluorescence state was off. Whereas the fluorescence of NS-CDs can be switched on when a trace amount of H2 O2 was added. Based on this novel phenomenon, the peroxidase-like activity of NS-CDs-AgNPs by using 3,3',5,5'-tetramethylbenzidine (TMB) chromogen and H2 O2 as substrates was evaluated. The Km values of the prepared probe for H2 O2 and TMB were 0.84 mM and 0.01 mM with the Vm of 6.65 × 10-8 M S-1 and 3.01 × 10-8 M S-1 , respectively. The results showed that NS-CDs-AgNPs had good peroxidase-like activity and strong affinity to TMB and H2 O2 . It confirmed that there is a redox interaction between AgNPs and H2 O2 , and H2 O2 can oxidize Ag to produce Ag+ , which is the main reason that the fluorescence of NS-CDs-AgNPs can be activated by H2 O2 . The hydroxyl radical (·OH) was formed in the process of reaction, which can further oxidize TMB for color reaction. Meanwhile, glucose can be oxidized to produce H2 O2 in the presence of glucose oxidase (GOx). Based on the phenomenon, a fluorimetric and colorimetric dual-mode sensor for glucose detection was established. Satisfactory results were obtained with the linear range of 0.1-80 μM for fluorimetric mode and 0.5-5 μM for colorimetric mode, respectively. Additionally, the LOD was below 0.32 μM and 0.21 μM, respectively. The method was successfully applied to determine the glucose in human serum with satisfactory recovery and RSD., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
- Full Text
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45. Improving the Electrochemical Glycerol-to-Glycerate Conversion at Pd Sites via the Interfacial Hydroxyl Immigrated from Ni Sites.
- Author
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Zhang Y, Wang L, Pan S, Zhou L, Zhang M, Yang Y, and Cai W
- Abstract
The electrochemical conversion of glycerol into high-value chemicals through the selective glycerol oxidation reaction (GOR) holds importance in utilizing the surplus platform chemical component of glycerol. Nevertheless, it is still very limited in producing three-carbon chain (C
3 ) chemicals, especially glyceric acid/glycerate, through the direct oxidation of its primary hydroxyl group. Herein, Pd microstructure electrodeposited on the Ni foam support (Pd/NF) is designed and fabricated to achieve a highly efficient GOR, exhibiting a superior current density of ca. 120 mA cm-2 at 0.8 V vs. reversible hydrogen electrode (RHE), and high selectivity of glycerate at ca. 70%. The Faradaic efficiency of C3 chemicals from GOR can still be maintained at ca. 80% after 20 continuous electrolysis runs, and the conversion rate of glycerol can reach 95% after 10-h electrolysis. It is also clarified that the dual-component interfaces constructed by the adjacent Pd and Ni sites are responsible for this highly efficient GOR. Specifically, Ni sites can effectively strengthen the generative capacity of the active adsorbed hydroxyl (OHad ) species, which can steadily immigrate to the Pd sites, so that the surface adsorbed glycerol species are quickly oxidized into C3 chemicals, rather than breaking the C-C bond of glycerol; thus, neither form the C2 /C1 species. This study may yield fresh perspectives on the electrocatalytic conversion of glycerol into high-value C3 chemicals, such as glyceric acid/glycerate.- Published
- 2024
- Full Text
- View/download PDF
46. Visible-Light-Induced Metal- and Photosensitizer-Free C(sp 3 )-H Phosphorylation of 3,4-Dihydroquinoxalin-2(1 H )-ones with Diphenylphosphine Oxide.
- Author
-
Jia L, Lu Y, Chen Y, Zhong Y, Zhao F, and Zhou Y
- Abstract
Herein, we report a direct phosphorylation of the C(sp
3 )-H bond of 3,4-dihydroquinoxalin-2(1 H )-ones using oxygen as a green oxidant under visible light at room temperature. This transformation was readily accomplished in the absence of metal and photosensitizer to construct new C(sp3 )-P bonds and provide a series of phosphonylated dihydroquinoxalin-2-ones in good to excellent yields. This approach opens straightforward and environmentally friendly access to 3-phosphoryl quinoxalin-2-ones derivatives.- Published
- 2024
- Full Text
- View/download PDF
47. Research Advances of Cathode Materials for Rechargeable Aluminum Batteries.
- Author
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Gao Y, Zhang D, Zhang S, and Li L
- Abstract
Rechargeable aluminum ion batteries (AIBs) have recently gained widespread research concern as energy storage technologies because of their advantages of being safe, economical, environmentally friendly, sustainable, and displaying high performance. Nevertheless, the intense Coulombic interactions between the Al
3+ ions with high charge density and the lattice of the electrode body lead to poor cathode kinetics and limited cycle life in AIBs. This paper reviews the recent advances in the cathode design of AIBs to gain a comprehensive understanding of the opportunities and challenges presented by current AIBs. In addition, the advantages, limitations, and possible solutions of each cathode material are discussed. Finally, the future development prospect of the cathode materials is presented., (© 2024 The Chemical Society of Japan and Wiley-VCH GmbH.)- Published
- 2024
- Full Text
- View/download PDF
48. Fiddler crabs (Tubuca arcuata) as bioindicators of microplastic pollution in mangrove sediments.
- Author
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Xu X, He L, Huang F, Jiang S, Dai Z, Sun R, and Li C
- Abstract
In recent years, microplastics (MPs) have been widely found in the environment and pose potential risks to ecosystems, which attracted people's attention. Using bioindicators has been a great approach to understanding the pollution levels, bioavailability, and ecological risks of pollutants. However, only few studies have investigated MPs in mangrove ecosystems, with few bioindicators of MPs. Herein, the distribution of MPs in mangrove sediments and fiddler crabs (Tubuca arcuata) in mangroves was investigated. Results showed that the abundance values of MPs are 1160‒12,120 items/kg and 11-100 items/ind. in mangrove sediments and fiddler crabs, respectively. The dominant shape of MPs detected in mangrove sediments and fiddler crabs was fragments with sizes of 20‒1000 μm, larger MPs of 50-1000 μm were found in abundance. Polypropylene (PP), which is one of the most commonly used plastic materials, was the main polymer type. The distribution of MPs in fiddler crabs closely resembled that in surface mangrove sediments with a strong linear correlation (R
2 > 0.8 and p < 0.05) between their abundance. Therefore, the MP contamination level in mangrove sediments can be determined by studying MP pollution in fiddler crabs. Moreover, the results of the target group index (TGI) indicated that fiddler crabs prefer feeding specific MPs in mangrove sediments. Our findings demonstrate the suitability of fiddler crabs as bioindicators for assessing MP pollution in mangrove sediments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
49. Deep eutectic solvents as sustainable extraction media for extraction of polysaccharides from natural sources: Status, challenges and prospects.
- Author
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Yahaya N, Mohamed AH, Sajid M, Zain NNM, Liao PC, and Chew KW
- Subjects
- Biological Products chemistry, Biological Products isolation & purification, Animals, Solvents chemistry, Chemical Fractionation methods, Plants chemistry, Polysaccharides chemistry, Polysaccharides isolation & purification, Deep Eutectic Solvents chemistry
- Abstract
Deep eutectic solvents (DES) emerge as promising alternatives to conventional solvents, offering outstanding extraction capabilities, low toxicity, eco-friendliness, straightforward synthesis procedures, broad applicability, and impressive recyclability. DES are synthesized by combining two or more components through various synthesis procedures, such as heat-assisted mixing/stirring, grinding, freeze drying, and evaporation. Polysaccharides, as abundant natural materials, are highly valued for their biocompatibility, biodegradability, and sustainability. These versatile biopolymers can be derived from various natural sources such as plants, algae, animals, or microorganisms using diverse extraction techniques. This review explores the synthesis procedures of DES, their physicochemical properties, characterization analysis, and their application in polysaccharide extraction. The extraction optimization strategies, parameters affecting DES-based polysaccharide extraction, and separation mechanisms are comprehensively discussed. Additionally, this review provides insights into recently developed molecular guides for DES screening and the utilization of artificial neural networks for optimizing DES-based extraction processes. DES serve as excellent extraction media for polysaccharides from different sources, preserving their functional features. They are utilized both as extraction solvents and as supporting media to enhance the extraction abilities of other solvents. Continued research aims to improve DES-based extraction methods and achieve selective, energy-efficient processes to meet the demands of this expanding field., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
50. Efficient adsorption of cationic dyes by a novel honeycomb-like porous hydrogel with ultrahigh mechanical property.
- Author
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Wang Y, Fang LP, Zhang HY, Ren JJ, Liang T, Lv XB, Cheng CJ, and Yu HR
- Abstract
The optimization of hydrogel structure is crucial for adsorption capacity, mechanical stability, and reusability. Herein, a chitosan and laponite-XLS co-doped poly(acrylic acid-co-acrylamide) hydrogel (CXAA) with honeycomb-like porous structures is synthesized by cooperative cross-linking of 2-hydroxypropyltrimethyl ammonium chloride chitosan (HACC) and laponite-XLS in reticular frameworks of acrylic acid (AAc) and acrylamide (AM). The CXAA exhibits extraordinary mechanical performances including tough tensile strength (3.36 MPa) and elasticity (2756 %), which facilitates recycling in practical adsorption treatment and broadens potential applications. Since the regular porous structures can fully expose numerous adsorption sites and electronegative natures within polymer materials, CXAA displays efficient and selective adsorption properties for cationic dyes like methylene blue (MB) and malachite green (MG) from mixed pollutants and can reach record-high values (MB = 6886 mg g
-1 , MG = 11,381 mg g-1 ) compared with previously reported adsorbents. Therefore, CXAA exhibits promising potential for separating cationic and anionic dyes by their charge disparities. Mechanism studies show that the synergistic effects of HACC, laponite-XLS, and functional groups in monomers promote highly efficient adsorption. Besides, the adsorption capacity of CXAA remains stable even after undergoing five cycles of regeneration. The results confirm that CXAA is a promising adsorbent for effectively removing organic dyes in wastewater., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)- Published
- 2024
- Full Text
- View/download PDF
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