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Atmospheric Pollutants in a Commercial Region of Fortaleza, Ceará, Brazil: Integration of Health, Environment and Economy in Urban Planning to Improve Air Quality
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作者 Mônica Giovana Alves Cardoso Ratts Brenna Kessy Silva Lima +5 位作者 Gilvan Ribeiro dos Santos Fladimir de Lima Gondim Rinaldo Santos Araújo Mona Lisa Moura de Oliveira Francisco Sales Ávila Cavalcante Daniel Silveira Serra 《Journal of Geoscience and Environment Protection》 2024年第5期92-112,共21页
The accelerated growth of the vehicular fleet, the modernization of large urban centers, and the few adjustments to the road network in Fortaleza have intensified the problems of traffic and emissions of atmospheric p... The accelerated growth of the vehicular fleet, the modernization of large urban centers, and the few adjustments to the road network in Fortaleza have intensified the problems of traffic and emissions of atmospheric pollutants, highlighting the necessity for strategic urban planning initiatives to address the escalating issues of traffic and pollution. With the objective of analyzing the indices of concentrations of atmospheric pollutants and estimating how these levels can affect human health, this work consists of a study of the analysis of air quality in the intense trade region of Fortaleza. For this, the analysis zone was divided into three perimeters (Major - Medium - Minor), where each perimeter was analyzed at 7 am, 12 noon and 5 pm. Concentrations of the type of O<sub>3</sub>, particulate matter (PM<sub>2.5</sub> and PM<sub>10</sub>), CO<sub>2</sub> and HCHO were collected. Our results demonstrate that most of the analyses are within the limits of current legislation;however, at certain times and perimeters, the analyses of CO<sub>2</sub> and HCHO exceeded the established limits. In view of the above, we conclude that public policies to control air quality are necessary to reduce the damage to human health and the environment caused by pollutants. 展开更多
关键词 Air Quality Urban Planning Particulate Material Health Impacts
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Synthesis,Crystal Structure and Quantum Chemistry of the Complex [Cu(p-FBA)_2(phen)(H_2O)]
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作者 季宁宁 石智强 赵仁高 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第10期1587-1592,共6页
A novel metal-organic complex Cu(p-FBA)2(phen)(H2O) (p-FBA = p-fluorobenzoic acid,phen = 1,10-phenanthroline) has been synthesized and structurally characterized by X-ray single-crystal diffraction,elemental a... A novel metal-organic complex Cu(p-FBA)2(phen)(H2O) (p-FBA = p-fluorobenzoic acid,phen = 1,10-phenanthroline) has been synthesized and structurally characterized by X-ray single-crystal diffraction,elemental analysis and IR spectra. The crystal belongs to triclinic,space group P1 with a = 7.8043(7),b = 10.4069(9),c = 14.3658(13) ,α = 105.3170(10),β = 96.877(2),γ = 96.7580(10)o,V = 1103.56(17) 3,Mr = 539.96,Z = 2,Dc = 1.625 g/cm3,μ = 1.050 mm-1,F(000) = 550,the final R = 0.0324 and wR = 0.0952. In the crystal,the structure consists of discrete molecules containing a five-coordinate copper(Ⅱ ) in a distorted square pyramidal configuration. Intramolecular O-H···O hydrogen bonds,weak intermolecular C-H···O hydrogen bonds and π-π stacking link the molecules into a one-dimensional chain structure. The study on the title complex has been performed with quantum chemistry calculation by means of G03W package on the Lanl2dz basis set. The stabilities of the complex together with the orbital energies and composition characteristics of some frontier molecular orbitals have been investigated. 展开更多
关键词 copper(II) complex crystal structure quantum chemistry calculation
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Comparison of Conventional and Microwave-assisted Synthesis and Characteristics of Aluminum-pillared Rectorite 被引量:4
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作者 杜冬云 陆晓华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第2期53-56,共4页
The synthesis and characterization of aluminum-pillared rectorite were studied. The synthesis was conducted with both conventional heating and microwave irradiation. Microwave irradiation was found to enhance the inte... The synthesis and characterization of aluminum-pillared rectorite were studied. The synthesis was conducted with both conventional heating and microwave irradiation. Microwave irradiation was found to enhance the intercalation and ion-exchange during synthesis, and to be able to produce the rectorite with a larger d_(001) and a better uniformity. The specific surface area is 180 m^2/g and basal spacing is 3.2 nm. The texture change and thermal and hydrothermal stability of cross-linked rectorite were examined using XRD, FTIR, nitrogen-adsorption and TGA. The experimental results show that the aluminum-pillared rectorite, after calcined at 800 ℃ for 3 hours, can keep the basal aluminum-silicate texture and would not disperse in water at room or an elevated temperature. The aluminum-pillared rectorite shows a high specific surface area, good thermal and hydrothermal stability, and is promising in applications as catalyst carriers and adsorbents for waste treatment. 展开更多
关键词 RECTORITE pillared-clay microwave irradiation CATALYSIS adsorption
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Hydrothermal Synthesis,Crystal Structure and Thermal Stability of a Novel Water Cluster [Mn(phen)_2·H_2O·Cl]·p-FBA·3H_2O 被引量:1
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作者 季宁宁 石智强 赵仁高 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第10期1495-1500,共6页
A novel water cluster [Mn(phen)2·H2O·Cl]·p-FBA·3H2O (p-FBA = p-fluorobenzoic acid and phen = 1,10-phenanthroline) was synthesized by the hydrothermal reaction of MnCl2 with p-FBA and phen at 1... A novel water cluster [Mn(phen)2·H2O·Cl]·p-FBA·3H2O (p-FBA = p-fluorobenzoic acid and phen = 1,10-phenanthroline) was synthesized by the hydrothermal reaction of MnCl2 with p-FBA and phen at 150 ℃ and characterized by elemental analysis,IR spectra and TG. Its crystal structure was determined by X-ray single-crystal diffraction study. The crystal belongs to the triclinic system,space group P1,with a = 10.5768(1),b = 11.5960(1),c = 12.9916(2) ,α = 101.816(2),β = 95.397(2),γ = 103.052(2)o,V = 1502.8(3) 3,Z = 2,Dc = 1.463 g/cm3,R = 0.0399 and wR = 0.0997. The crystal structure shows that the manganese(Ⅱ ) ion is six-coordinated by four nitrogen atoms,one chloride ion and one oxygen atom forming a distorted octahedral coordination geometry. The structure includes three acyclically connected water molecules and one coordinated water molecule thus forming a (H2O)4 water cluster. This water pattern forms a cross-linked discrete ring. The steady (H2O)4 is further extended into a cage-like structure by the hydrogen-bonding interaction formed by dissociative aqua molecule and Cl-ligand. The dimer structure is further extended into a one-dimensional (1D) structure through C-H···O interaction. π···π Stacking interaction among adjacent phen aromatic rings further stabilizes the crystal structure. 展开更多
关键词 water cluster manganese( complex crystal structure thermal stability
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Analysis of pollutant components in landfill leachate from hinterland landfill in Three Gorge Water Reservoir 被引量:1
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作者 YANG Ji-dong 《Journal of Environmental Science and Engineering》 2008年第5期14-20,共7页
This paper mainly discusses the protection of water resource environment in Three Gorge Water Reservoir, a systematic investigation and analysis of the landfill leachate's polluting components, hazardous and changing... This paper mainly discusses the protection of water resource environment in Three Gorge Water Reservoir, a systematic investigation and analysis of the landfill leachate's polluting components, hazardous and changing rule in landfill leachate from hinterland landfill located in the surrounding area have been carried out, and proposed the countermeasures for disposition the leachate furtherly. 展开更多
关键词 garbage disposal landfill leachate pollutantcomponents
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Geometric,stable and electronic properties of Au_(n-2)Y_2(n=3-8) clusters
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作者 齐凯天 毛华平 +1 位作者 王红艳 盛勇 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第3期293-297,共5页
Employing first-principles methods, based on the density function theory, and using the LANL2DZ basis sets, the ground-state geometric, the stable and the electronic properties of Aun-2Y2 clusters are investigated in ... Employing first-principles methods, based on the density function theory, and using the LANL2DZ basis sets, the ground-state geometric, the stable and the electronic properties of Aun-2Y2 clusters are investigated in this paper. Meanwhile, the differences in property among pure gold clusters, pure yttrium clusters, gold clusters doped with one yttrium atom, and gold clusters doped with two yttrium atoms are studied. We find that when gold clusters are doped by two yttrium atoms, the odd-even oscillatory behaviours of Aun-1Y and Aun disappear. The properties of Aun-2Y2 clusters are close to those of pure yttrium clusters. 展开更多
关键词 Aun-2Y2 clusters density function theory geometric property electronic property
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Density functional study on structural and electronic properties of bimetallic gold-yttrium clusters: comparison with pure gold and yttrium clusters
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作者 毛华平 王红艳 盛勇 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2110-2115,共6页
Employing first-principles methods, based on the density functional theory, this paper investigates the ground state geometric and electronic properties of pure gold clusters, pure yttrium clusters and gold clusters d... Employing first-principles methods, based on the density functional theory, this paper investigates the ground state geometric and electronic properties of pure gold clusters, pure yttrium clusters and gold clusters doped each with one yttrium atom. It is shown that the average bond lengths in the Aun-1Y(n≤9) bimetallic clusters are shorter than those in the corresponding pure gold and yttrium clusters. The most stable isomers of the yttrium-doped gold clusters tend to equally delocalize valence s, p and d electrons of the constituent atoms over the entire structure. The Y atom has maximum number of neighbouring Au atom, which tends to be energetically favourable in the lowest-energy equilibrium structures, because the Au-Y bond is stronger than the Au-Au bond. The three-dimensional isomers of Aun-1Y structures are found in an early appearance starting at n=5 (Au4Y). Calculated vertical ionization potential and electron affinities as a function of the cluster size show odd-even oscillatory behaviour, and resemble pure gold clusters. However, one of the most striking feature of pure yttrium clusters is the absence of odd-even alternation, in agreement with mass spectrometric observations. The HOMO LUMO gap of Au3Y is the biggest in all the doped Aun-1Y(n≤9) bimetallic clusters. 展开更多
关键词 gold-yttrium bimetallic cluster density functional theory HOMO-LUMO gap equilib- rium structure
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Preparation and enantiosorption of L-aspartic acid pillared hydrotalcites
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作者 彭霞辉 黄可龙 《Journal of Central South University of Technology》 EI 2007年第4期520-523,共4页
L-aspartic acid (Asp) pillared hydrotalcites were prepared by direct reaction of the L-Asp anion with layered double hydroxides (LDHs). The obtained samples were characterized by X-ray diffractometry (XRD), Four... L-aspartic acid (Asp) pillared hydrotalcites were prepared by direct reaction of the L-Asp anion with layered double hydroxides (LDHs). The obtained samples were characterized by X-ray diffractometry (XRD), Fourier transform infrared (FTIR), and thermogravimetric and differential thermal analysis (TG/DTA). The results show that the initial interlayer carbonate ions can be completely replaced by the L-Asp anion under the controlled conditions. The pillared hydrotalcites have a crystallized supramolecular structure and thermal stability. The L-Asp pillared LDHs were used in the enantiosorption of enantiopure phenylalanine (Pile), the results suggest that L-Asp pillared LDHs exhibit an excellent enantiosorption capability for D-Phe, and the adsorption isotherm fits Freundlich equation. 展开更多
关键词 L-aspartic acid HYDROTALCITES PREPARATION enantiosorption PHENYLALANINE
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Determination of heavy metal ion in landfill leachate with solvent extracting & fluorescence quenching method
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作者 YANG Ji-dong 《Journal of Environmental Science and Engineering》 2008年第10期24-29,79,共7页
Add the masking agent and biscyclohexanoneoxalyldihydraone into the diluted clarificd liquid of the landfill leachate which was treatmented by digestion and centrifugal filtration to complexate all heavy metal ion in ... Add the masking agent and biscyclohexanoneoxalyldihydraone into the diluted clarificd liquid of the landfill leachate which was treatmented by digestion and centrifugal filtration to complexate all heavy metal ion in the trcatmented liquid, and extracted using CHCl3 many time, then it were demasking and decomposing respectively, and adjusted different pH and formed Me^n+-PAN coordination compound when these metal ion reaction with PAN. The Fluoresence quenching of Rh6G (λex/λem=543mn/558nm) when the metal ion coordination compound was add into the Rh6G solution step by step, the quenching intensity was directly proportional to the concentration of the metal ion in the certain range. So a new method of fast and simple for determination of trace metal ion in landfill lcachate was established to determine metal ion in sample of different landfill leachate in Three Gorge Water Reservoir, and comparison the classic assay method with satisfactory results. 展开更多
关键词 landfill leachate metal ion rhodamine 6G fluorescence quenching method 1- (2-pyridine-eazo)-2naphthol
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Fruit Waste and Sugarcane Bagasse as Potential Natural Resources of Mineral and Lipophilic Substances
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作者 Sonia Patricia Ordonez Crispin Humberto Garcia-Cruz +1 位作者 Mauricio Boscolo Jesus Eliecer Larrahondo 《Journal of Food Science and Engineering》 2015年第3期137-141,共5页
The objectives of this study were to explore alternatives for using fruit waste and sugarcane bagasse as important sources for new products and potential applications in the food industry. Fast foods are part of moder... The objectives of this study were to explore alternatives for using fruit waste and sugarcane bagasse as important sources for new products and potential applications in the food industry. Fast foods are part of modern life, as well as sources for producing biofuels based on biomass. The mineral content and compounds of nutritional interest, such as lipophilic substances, were determined in fruit waste (orange peels, passion fruit, bananas, grapes) and sugarcane bagasse. Significant differences were found in the samples tested, where minerals, such as potassium, nitrogen, zinc and iron, were found in fruit residues (bananas, oranges, passion fruit) and sugarcane bagasse. Banana residues were the most important source of minerals, followed by orange peels. Gas chromatography mass spectrography (GC-MS) analyses of the lipophilic fractions obtained from the plant residues revealed the presence of mostly saturated (palmitic, stearic) and unsaturated (oleic and linoleic) fatty acids, as well as other nutritionally valuable compounds, such as antioxidants (flavones in orange residues). The residues studied here can be used for future research to optimize pretreatment and hydrolysis of biomass for bioethanol production. 展开更多
关键词 BIOMASS fruit waste MINERALS lipophilic substances sugarcane bagasse
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Phytochemical Study and Anti-nutritional Factors in Stems of Dioscorea praehensilis Benth(Dioscoreaceae)
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作者 Patience Mpia Ngelinkoto André-Marie Kassia Lokassa +5 位作者 Bernadin Bulumuka Jeff Kawaya Maliani Myriam Mukadi Ngondo Ruth Luntadila Mbuli Johnny Bopopi Mukoko Florent Biduaya Mukeba 《Journal of Botanical Research》 2021年第4期1-10,共10页
The aim of this research was to find and assay phytochemical compounds and various biological macromolecules of the tender stems of Dioscorea praehensilis benth and evaluate their antioxidant activity and to compare t... The aim of this research was to find and assay phytochemical compounds and various biological macromolecules of the tender stems of Dioscorea praehensilis benth and evaluate their antioxidant activity and to compare the content of oxalates and cyanogenetic glucosides between raw and cooked tender stems.The plant collection and identification,phytochemical evaluation:phytochemical screening,preliminary(qualitative)analyses and in vitro assays.Phytochemical screening was performed by qualitative methods.The estimation of the content of secondary metabolites was evaluated by spectrophotometry-UV.Antioxidant activity was evaluated using the ABTS and DPPH assays and preliminary composition by the gravimetric method.The results obtained show that the stems of Dioscorea praehensilis are devoid of certain important chemical groups,the flavonoids were not detected and they were rich in total polyphenols(17.22±0.16),tannins(19.32±0.52)and anthocyanins(25.22±0.04).Our extracts showed a lower antioxidant activity than that of positive controls.The samples are rich in carbohydrates and fiber,with low levels of proteins,lipids and ash.Dioscorea praehensilis has a high toxicity in HCN,but after a good cooking of about 1 hour,99.97%of the cyanide are eliminated and does not have many oxalates.The results obtained show that Dioscorea praehensilis has a high dietary value and can therefore be used as a nutritive food. 展开更多
关键词 OXALATE Total cyanide Anti-nutritional factors D.praehensilis Anthocyanes dosage
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Photocatalytic degradation of the dye sulforhodamine-B: A comparative study of different light sources 被引量:12
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作者 FANG Yan-fen HUANG Ying-ping +3 位作者 LIU De-fu HUANG Yang GUO Wei DAVID Johnson 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第1期97-102,共6页
The photocatalytic degradation of dye pollutant sulforhodamine-B (SRB) in aqueous titanium dioxide (TiO2) dispersions was examined under three lighting regimes: UV light (330 nm〈λ〈 380 nm), sunlight, and vis... The photocatalytic degradation of dye pollutant sulforhodamine-B (SRB) in aqueous titanium dioxide (TiO2) dispersions was examined under three lighting regimes: UV light (330 nm〈λ〈 380 nm), sunlight, and visible light (λ〉450 nm), all investigated at pH=2.5. Total organic carbon (TOC) and chemical oxygen demand (CODer) assays show that the degradation rate of SRB is much higher when irradiated with UV and sunlight compared with visible light. The temporal concentration changes of SRB illustrated a first-order reaction and the rate constant, k, is 0.197 min^-1, 0.152 min^-1, 0.027 min^-1, respectively, under the three lighting conditions. The final mineralized products were amine compounds identified by infrared spectrophotometry. When irradiated with visible light, the photocatalytic degradation rate could be improved by lowering the H2O2 concentration and inhibited by increasing the H2O2 concentration, but results contrary to the above were obtained when UV light was used for irradiation. 展开更多
关键词 TIO2 photocatalytic degradation sulforhodamine-B (SRB)
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In situ characterizations of advanced electrode materials for sodium-ion batteries toward high electrochemical performances 被引量:4
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作者 Xiu-Mei Lin Xin-Tao Yang +5 位作者 Hao-Ning Chen Yong-Liang Deng Wen-Han Chen Jin-Chao Dong Yi-Min Wei Jian-Feng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期146-164,I0004,共20页
Energy storage is an ever-growing global concern due to increased energy needs and resource exhaustion.Sodium-ion batteries(SIBs)have called increasing attention and achieved substantial progress in recent years owing... Energy storage is an ever-growing global concern due to increased energy needs and resource exhaustion.Sodium-ion batteries(SIBs)have called increasing attention and achieved substantial progress in recent years owing to the abundance and even distribution of Na resources in the crust,and the predicted low cost of the technique.Nevertheless,SIBs still face challenges like lower energy density and inferior cycling stability compared to mature lithium-ion batteries(LIBs).Enhancing the electrochemical performance of SIBs requires an in-deep and comprehensive understanding of the improvement strategies and the underlying reaction mechanism elucidated by in situ techniques.In this review,commonly applied in situ techniques,for instance,transmission electron microscopy(TEM),Raman spectroscopy,X-ray diffraction(XRD),and X-ray absorption near-edge structure(XANES),and their applications on the representative cathode and anode materials with selected samples are summarized.We discuss the merits and demerits of each type of material,strategies to enhance their electrochemical performance,and the applications of in situ characterizations of them during the de/sodiation process to reveal the underlying reaction mechanism for performance improvement.We aim to elucidate the composition/structure-per formance relationship to provide guidelines for rational design and preparation of electrode materials toward high electrochemical performance. 展开更多
关键词 Sodium-ion batteries(SIBs) In situ characterizations Electrode materials Composition/structure-performance
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Interaction Between Mitoxantrone Metal Complex and Titan Yellow by Resonance Rayleigh Scattering Spectra and Its Analytical Application
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作者 HU Rong YANG Qiong +1 位作者 ZHANG Shu-ran YANG Ji-dong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第3期291-296,共6页
In a pH 2.4 Britton-Robinson buffer medium, the anthracycline antibiotics mitoxantrone(MXT) could react with metal ions such as Pd(Ⅱ), Co(Ⅱ) and Cu(Ⅱ) to form 1:2(molar ratio) cationic chelates, which fu... In a pH 2.4 Britton-Robinson buffer medium, the anthracycline antibiotics mitoxantrone(MXT) could react with metal ions such as Pd(Ⅱ), Co(Ⅱ) and Cu(Ⅱ) to form 1:2(molar ratio) cationic chelates, which further reacted with the anionic dye titan yellow to form 1:2 ternary ion-association complexes by electrostatic interaction. As a result, the intensity of resonance Rayleigh scattering(RRS) was enhanced greatly. These RRS spectral characteristics of various metal ion systems were similar, and the maximum RRS wavelengths were all located at 454 nm. But the increments of RRS intensities were different in the series of Pd(Ⅱ)〉Co(Ⅱ)〉Cu(Ⅱ). The enhanced RRS intensities were proportional to the concentration of MXT in a range of 0.03-2.4μg/mL and the detection limit(3σ) was 0.009μg/mL for the Pd(Ⅱ) system. In this study, the optimum conditions of the reactions and the effects of foreign substances were investigated, in addition, the composition and reaction mechanism of ion-association complexes were discussed. Thus a highly sensitive, simple and rapid method is proposed for the determination of MXT in urine and serum samples. 展开更多
关键词 Resonance Rayleigh scattering MITOXANTRONE Metal ion Titan yellow
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Phosphorous and selenium tuning Co-based non-precious catalysts for electrosynthesis of H_(2)O_(2)in acidic media 被引量:1
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作者 Jingxin Xie Lijie Zhong +6 位作者 Xin Yang Dequan He Kanglong Lin Xiaoxia Chen Huan Wang Shiyu Gan Li Niu 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期475-481,共7页
Electrosynthesis of hydrogen peroxide(H2O2)is an on-site method that enables independent distribution applications in many fields due to its small-scale and sustainable features.The crucial point remains developing hi... Electrosynthesis of hydrogen peroxide(H2O2)is an on-site method that enables independent distribution applications in many fields due to its small-scale and sustainable features.The crucial point remains developing highly active,selective and cost-effective electrocatalysts.The electrosynthesis of H2O2 in acidic media is more practical owing to its stability and no need for further purification.We herein report a phosphorus and selenium tuning Co-based non-precious catalyst(CoPSe)toward two-electron oxygen reduction reaction(2e–ORR)to produce H2O2 in acidic media.The starting point of using both P and Se is finding a balance between strong ORR activity of CoSe and weak activity of CoP.The results demonstrated that the CoPSe catalyst exhibited the optimized 2e–ORR activity compared with CoP and CoSe.It disclosed an onset potential of 0.68 V and the H2O2 selectivity 76%-85%in a wide potential range(0–0.5 V).Notably,the CoPSe catalyst overcomes a significant challenge of a narrow-range selectivity for transitionmetal based 2e–ORR catalysts.Finally,combining with electro-Fenton reaction,an on-site system was constructed for efficient degradation of organic pollutants.This work provides a promising non-precious Co-based electrocatalyst for the electrosynthesis of H2O2 in acidic media. 展开更多
关键词 Oxygen reduction reaction Electrochemical H2O2 production ELECTROCATALYSIS Non-precious electrocatalyst Acidic media
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In situ tracking of the lithiation and sodiation process of disodium terephthalate as anodes for rechargeable batteries by Raman spectroscopy
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作者 Xiu-Mei Lin Chong Han +6 位作者 Xin-Tao Yang Jia-Sheng Lin Wei-Qiang Yang Hong-Xu Guo Yao-Hui Wang Jin-Chao Dong Jian-Feng Li 《Nano Research》 SCIE EI CSCD 2024年第1期245-252,共8页
Organic compounds represent an appealing group of electrode materials for rechargeable batteries due to their merits of biomass,sustainability,environmental friendliness,and processability.Disodium terephthalate(Na_(2... Organic compounds represent an appealing group of electrode materials for rechargeable batteries due to their merits of biomass,sustainability,environmental friendliness,and processability.Disodium terephthalate(Na_(2)C_(8)H_(4)O_(4),Na_(2)TP),an organic salt with a theoretical capacity of 255 mAh·g^(-1),is electroactive towards both lithium and sodium.However,its electrochemical energy storage(EES)process has not been directly observed via in situ characterization techniques and the underlying mechanisms are still under debate.Herein,in situ Raman spectroscopy was employed to track the de/lithiation and de/sodiation processes of Na2TP.The appearance and then disappearance of the–COOLi Raman band at 1625 cm^(-1) during the de/lithiation,and the increase and then decrease of the–COONa Raman band at 1615 cm^(-1) during the de/sodiation processes of Na2TP elucidate the one-step with the 2Li+or 2Na+transfer mechanism.We also found that the inferior cycling stability of Na2TP as an anode for sodium-ion batteries(SIBs)than lithium-ion batteries(LIBs)could be due to the larger ion radium of Na+than Li+,which results in larger steric resistance and polarization during EES.The Na2TP,therefore,shows greater changes in spectra during de/sodiation than de/lithiation.We expect that our findings could provide a reference for the rational design of organic compounds for EES. 展开更多
关键词 disodium terephthalate(Na_(2)C_(8)H_(4)O_(4) Na2TP) in situ Raman spectroscopy de/lithiation de/sodiation mechanisms
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Sea urchin‐like NiMoO_(4) nanorod arrays as highly efficient bifunctional catalysts for electrocatalytic/photovoltage‐driven urea electrolysis 被引量:3
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作者 Chenxin Chen Suqi He +3 位作者 Kamran Dastafkan Zehua Zou Qingxiang Wang Chuan Zhao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1267-1276,共10页
Developing multifunctional electrocatalysts with high catalytic activity,longterm stability,and low cost is essential for electrocatalytic energy conversion.Herein,sea urchinlike NiMoO_(4) nanorod arrays grown on nick... Developing multifunctional electrocatalysts with high catalytic activity,longterm stability,and low cost is essential for electrocatalytic energy conversion.Herein,sea urchinlike NiMoO_(4) nanorod arrays grown on nickel foam has been developed as a bifunctional electrocatalyst for urea oxidation and hydrogen evolution.The NiMoO_(4)‐200/NF catalyst exhibits efficient activity toward hydrogen evolution reaction with a low overpotential of only 68 mV in 1.0 mol/L KOH to gain a current density of 10 mA cm^(–2).The NiMoO_(4)‐300/NF catalyst exhibits a prominent oxygen evolution reaction(OER)catalytic activity with an overpotential of 288 mV at 50 mA cm^(–2),as well as for urea oxidation reaction with an ultralow potential of 1.36 V at 10 mA cm^(–2).The observed difference in electrocatalytic activity and selectivity,derived by temperature variation,is ascribed to different lattice oxygen contents.The lattice oxygen of NiMoO_(4)‐300/NF is more than that of NiMoO_(4)‐200/NF,and the lattice oxygen is conducive to the progress of OER.A urea electrolyzer was assembled with Ni‐MoO_(4)‐200/NF and NiMoO_(4)‐300/NF as cathode and anode respectively,delivering a current density of 10 mA cm^(–2)at a cell voltage of merely 1.38 V.The NiMoO_(4)nanorod arrays has also been successfully applied for photovoltage‐driven urea electrolysis and hydrogen production,revealing its great potential for solar‐driven energy conversion. 展开更多
关键词 NiMoO4 nanorod Bifunctional electrocatalyst Urea electrolysis Photovoltage‐driven Lattice oxygen Sea urchin‐like
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Synthesis of core-shell structured Au@Bi2S3 nanorod and its application as DNA immobilization matrix for electrochemical biosensor construction 被引量:2
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作者 Feng Gao Juan Song +4 位作者 Bin Zhang Hidekazu Tanaka Fei Gao Weiwei Qiu Qingxiang Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第1期181-184,共4页
The core-shell structured Au@Bi2S3 nanorods have been prepared through direct in-situ growth of Bi2S3 at the surface of pre-synthesized gold nanorods.The product was characterized by X-ray diffraction,transmission ele... The core-shell structured Au@Bi2S3 nanorods have been prepared through direct in-situ growth of Bi2S3 at the surface of pre-synthesized gold nanorods.The product was characterized by X-ray diffraction,transmission electron microscopy and energy-dispersive X-ray spectroscopy.Then the obtained Au@Bi2S3 nanorods were coated onto glassy carbon electrode to act as a scaffold for fabrication of electrochemical DNA biosensor on the basis of the coordination of-NH2 modified on 5’-end of probe DNA and Au@Bi2S3.Electrochemical characterization assays demonstrate that the Au@Bi2S3 nanorods behave as an excellent electronic transport channel to promote the electron transfer kinetics and increase the effective surface area by their nanosize effect.The hybridization experiments reveal that the Au@Bi2S3 matrix-based DNA biosensor is capable of recognizing complementary DNA over a wide concentration ranging from 10 fmol/L to 1 nmol/L.The limit of detection was estimated to be 2 fmol/L(S/N=3).The biosensor also presents remarkable selectivity to distinguish fully complementa ry sequences from basemismatched and non-complementary ones,showing great promising in practical application. 展开更多
关键词 DNA biosensor Au@Bi2S3 nanorods Electrochemical impedance spectroscopy Core-shell structure Bi^3+-N bond Probe immobilization
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Investigation of Thermal Decomposition of Ascorbic Acid by TG-FTIR and Thermal Kinetics Analysis Shi Jingyan
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作者 史竞艳 LIU Yuwen +1 位作者 WANG Zhiyong WANG Cunxin 《武汉生物工程学院学报》 2014年第4期286-291,共6页
The thermal behavior of dry solid ascorbic acid in nitrogen atmosphere in the temperature range of 25<sup>8</sup>00℃was investigated by TG-FTIR.During the thermal decomposition process,five evolved gaseou... The thermal behavior of dry solid ascorbic acid in nitrogen atmosphere in the temperature range of 25<sup>8</sup>00℃was investigated by TG-FTIR.During the thermal decomposition process,five evolved gaseous species,including H<sub>2</sub>O,CO<sub>2</sub>,CO,CH<sub>4</sub> and HCOOH,were identified and monitored,in which HCOOH was detected for the first time.The results indicated that ascorbic acid began to decompose at 191℃.Its decomposition process consisted of three stages,and dehydration and decarboxylation to form furfural were the possible principal mechanism.The kinetic analysis for the first decomposition stage was also carried out by the isoconversional method and the master plots method.The results indicated that this process can be described by the model of 1st order reaction. 展开更多
关键词 ascorbic acid thermal decomposition TG-FTIR therma
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In situ Raman,FTIR,and XRD spectroscopic studies in fuel cells and rechargeable batteries 被引量:5
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作者 Fan Gao Xiang-Dong Tian +3 位作者 Jia-Sheng Lin Jin-Chao Dong Xiu-Mei Lin Jian-Feng Li 《Nano Research》 SCIE EI CSCD 2023年第4期4855-4866,共12页
As state-of-the-art electrochemical energy conversion and storage(EECS)techniques,fuel cells and rechargeable batteries have achieved great success in the past decades.However,modern societies’ever-growing demand in ... As state-of-the-art electrochemical energy conversion and storage(EECS)techniques,fuel cells and rechargeable batteries have achieved great success in the past decades.However,modern societies’ever-growing demand in energy calls for EECS devices with high efficiency and enhanced performance,which mainly rely on the rational design of catalysts,electrode materials,and electrode/electrolyte interfaces in EESC,based on in-deep and comprehensive mechanistic understanding of the relevant electrochemical redox reactions.Such an understanding can be realized by monitoring the dynamic redox reaction processes under realistic operation conditions using in situ techniques,such as in situ Raman,Fourier transform infrared(FTIR),and X-ray diffraction(XRD)spectroscopy.These techniques can provide characteristic spectroscopic information of molecules and/or crystals,which are sensitive to structure/phase changes resulted from different electrochemical working conditions,hence allowing for intermediates identification and mechanisms understanding.This review described and summarized recent progress in the in situ studies of fuel cells and rechargeable batteries via Raman,FTIR,and XRD spectroscopy.The applications of these in situ techniques on typical electrocatalytic electrooxidation reaction and oxygen reduction reaction(ORR)in fuel cells,on representative high capacity and/or resource abundance cathodes and anodes,and on the solid electrolyte interface(SEI)in rechargeable batteries are discussed.We discuss how these techniques promote the development of novel EECS systems and highlight their critical importance in future EECS research. 展开更多
关键词 in situ spectroscopy RAMAN Fourier transform infrared spectroscopy(FTIR) X-ray diffraction(XRD) fuel cells rechargeable batteries
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