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Evaluating the Derivative Value of Smart Grid Investment under Dual Carbon Target: A Hybrid Multi-Criteria Decision-Making Analysis
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作者 Na Yu Changzheng Gao +2 位作者 Xiuna Wang Dongwei Li Weiyang You 《Energy Engineering》 EI 2023年第12期2879-2901,共23页
With the goal of“carbon peaking and carbon neutralization”,it is an inevitable trend for investing smart grid to promote the large-scale grid connection of renewable energy.Smart grid investment has a significant dr... With the goal of“carbon peaking and carbon neutralization”,it is an inevitable trend for investing smart grid to promote the large-scale grid connection of renewable energy.Smart grid investment has a significant driving effect(derivative value),and evaluating this value can help to more accurately grasp the external effects of smart grid investment and support the realization of industrial linkage value with power grid investment as the core.Therefore,by analyzing the characterization of the derivative value of smart grid driven by investment,this paper constructs the evaluation index system of the derivative value of smart grid investment including 11 indicators.Then,the hybrid evaluation model of the derivative value of smart grid investment is developed based on anti-entropy weight(AEW),level based weight assessment(LBWA),and measurement alternatives and ranking according to the compromise solution(MARCOS)techniques.The results of case analysis show that for SG investment,the value of sustainable development can better reflect its derivative value,and when smart grid performs poorly in promoting renewable energy consumption,improving primary energy efficiency,and improving its own fault resistance,the driving force of its investment for future sustainable development will decline significantly,making the grid investment lack derivative value.In addition,smart grid investment needs to pay attention to the economy of investment,which is an important guarantee to ensure that the power grid has sufficient and stable sources of investment funds.Finally,compared with three comparison models,the proposed hybrid multi-criteria decision-making(MCDM)model can better improve the decision-making efficiency on the premise of ensuring robustness. 展开更多
关键词 carbon peaking and carbon neutralization smart grid investment derivative value combination weighting MARCOS sustainable development performance
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Biomass-derived porous carbon materials for advanced lithium sulfur batteries 被引量:15
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作者 Poting Liu Yunyi Wang Jiehua Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第7期171-185,共15页
Biomass, as the most widely used carbon sources, is the main ingredient in the formation of fossil fuels. Biomass-derived novel carbons(BDNCs) have attracted much attention because of its adjustable physical/chemical ... Biomass, as the most widely used carbon sources, is the main ingredient in the formation of fossil fuels. Biomass-derived novel carbons(BDNCs) have attracted much attention because of its adjustable physical/chemical properties, environmentally friendliness, and considerable economic value. Nature contributes to the biomass with bizarre microstructures with micropores, mesopores or hierarchical pores.Currently, it has been confirmed that biomass has great potential applications in energy storage devices,especially in lithium-sulfur(Li–S) batteries. In this article, the synthesis and function of BDNCs for Li–S batteries are presented, and the electrochemical effects of structural diversity, porosity and surface heteroatom doping of the carbons in Li-S batteries are discussed. In addition, the economic benefits, new trends and challenges are also proposed for further design excellent BDNCs for Li–S batteries. 展开更多
关键词 Biomass-derived carbon materials Lithium-sulfur battery Porous carbon Carbohydrate Cellulose
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Biomass-derived nitrogen-doped hierarchical porous carbon as efficient sulfur host for lithium–sulfur batteries 被引量:16
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作者 Qinghuiqiang Xiao Gaoran Li +6 位作者 Minjie Li Ruiping Liu Haibo Li Pengfei Ren Yue Dong Ming Feng Zhongwei Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期61-67,共7页
Lithium-sulfur(Li-S) battery is a potential energy storage technology with high energy density and low cost. However, the gap between theoretical expectation and practical performance limits its wide implementation. H... Lithium-sulfur(Li-S) battery is a potential energy storage technology with high energy density and low cost. However, the gap between theoretical expectation and practical performance limits its wide implementation. Herein, we report a nitrogen-doped porous carbon derived from biomass pomelo peel as sulfur host material for Li-S batteries. The hierarchical porous architecture and the polar surface introduced by N-doping render a favorable combination of physical and chemical sulfur confinements as well as an expedite electron/ion transfer, thus contributing to a facilitated and stabilized sulfur electrochemistry. As a result, the corresponding sulfur composite electrodes exhibit an ultrahigh initial capacity of 1534.6 mAh g^-1, high coulombic efficiency over 98% upon 300 cycles, and decent rate capability up to 2 C. This work provides an economical and effective strategy for the fabrication of advanced carbonaceous sulfur host material as well as the significant improvement of Li-S battery performance. 展开更多
关键词 Biomass-derived material Porous carbon LITHIUM SULFUR BATTERIES Electrochemical performance
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Electrochemical Performance of Core-Sheath Dip-Coated Lignin Derived Carbon/Wet-Spun Graphene Electrodes for Fiber-Shaped Supercapacitors 被引量:1
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作者 HU Wenxin LIU Yan +10 位作者 XIANG Ruifang JING Yuanyuan XU Qingli ZHANG Juan HU Xuefeng JIN Yanhong YANG Xiaona CHENG Yu LIN Jiaxian ZHANG Kun LU Chunhong 《Journal of Donghua University(English Edition)》 CAS 2021年第2期91-98,共8页
One-dimensional graphene fibers(GFs)possess excellent properties,including high electrical conductivity,good physical and chemical stability,high thermal conductivity,flexibility,etc.GFs are ideal electrode materials ... One-dimensional graphene fibers(GFs)possess excellent properties,including high electrical conductivity,good physical and chemical stability,high thermal conductivity,flexibility,etc.GFs are ideal electrode materials for fiber-shaped supercapacitors.However,due to the lack of an effective method to manufacture GFs with high specific capacitance,their low energy density hinders their practical application.Herein,we decorated wet-spun graphene oxide fibers(GOFs)by dip-coating them with graphene oxide(GO)solutions containing different contents of lignin to obtain a core-sheath lignin/GO composite fibers.After carbonization and activation,we successfully prepared lignin derived carbon/GF electrodes.The assembled fiber-shaped supercapacitors(FSSCs)exhibit a specific capacitance of 9.98 mF/cm^(2)and an energy density of 0.89μW·h/cm^(2),about 6 times of those of pure GFs(1.57 mF/cm^(2)and 0.14μW·h/cm^(2),respectively),long cycling life and cycling stability.This suggests that the introduction of lignin derived carbon into GFs can effectively increase the specific capacitance and the energy density of FSSCs. 展开更多
关键词 WET-SPINNING lignin derived carbon GRAPHENE specific capacitance energy density
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Effects of thermal activation conditions on the microstructure regulation of corncob-derived activated carbon for hydrogen storage 被引量:7
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作者 Dabin Wang Zhen Geng +2 位作者 Cunman Zhang Xiangyang Zhou Xupeng Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2014年第5期601-608,共8页
Activated carbons derived from corncob (CACs) were prepared by pyrolysis carbonization and KOH activation. Through modifying activation conditions, samples with large pore volume and ultrahigh BET specific surface a... Activated carbons derived from corncob (CACs) were prepared by pyrolysis carbonization and KOH activation. Through modifying activation conditions, samples with large pore volume and ultrahigh BET specific surface area could be obtained. The sample achieved the highest hydrogen uptake capacity of 5.80 wt% at 40 bar and -196℃ The as-obtained samples were characterized by N2-sorption, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Besides, thermogravimetric analysis was also employed to investigate the activation behavior of CACs. Detailed investigation on the activation parameters reveals that moderate activation temperature and heating rate are favorable for preparing CACs with high surface area, large pore volume and optimal pore size distribution. Meanwhile, the micropore volume between 0.65 nm and 0.85 nm along with BET surface area and total pore volume has great effects on hydrogen uptake capacities. The present results indicate that CACs are the most promising materials for hydrogen storage application. 展开更多
关键词 corncob-derived activated carbon KOH activation activation conditions hydrogen storage
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Lignin derived multi-doped(N, S, Cl) carbon materials as excellent electrocatalyst for oxygen reduction reaction in proton exchange membrane fuel cells 被引量:7
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作者 Yixing Shen Yuhang Li +3 位作者 Guangxing Yang Qiao Zhang Hong Liang Feng Peng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期106-114,共9页
Nowadays,hierarchically macro-/meso-/microporous 3D carbon materials have been paid more attention due to their imaginative application potential in specific electrochemistry.Here,we report a dualtemplate strategy usi... Nowadays,hierarchically macro-/meso-/microporous 3D carbon materials have been paid more attention due to their imaginative application potential in specific electrochemistry.Here,we report a dualtemplate strategy using eutectic NaCl/ZnCl2 melt as airtight and swelling agent to obtain 3D mesoporous skeleton structured carbon from renewable lignin.The prepared lignin-derived biocarbon material(LN-3-1)has a high specific surface area(1289 m^2 g^-1),a large pore volume(2.80 cm^3 g^-1),and a well-connected and stable structure.LN-3-1 exhibits extremely high activity and stability in acidic medium for oxygen reduction reaction(ORR),superior to Pt/C catalyst and most non noble-metal catalysts reported in recent literatures.The prepared carbon material was used as a cathode catalyst to assemble a H2-O2 single fuel cell,and its excellent catalytic performance has been confirmed with the maximum power density of 779 mW cm^-2,which is one of the highest power densities among non-metallic catalysts so far.Density functional theory(DFT)calculations indicate that the synergy of chlorine and nitrogen reconciles the intermediate adsorption energies,leading to an appropriate theoretical ORR onset potential.We develop a cost-effective and highly efficient method to prepare biocarbon catalyst for ORR in proton-exchange membrane fuel cells. 展开更多
关键词 ELECTROCATALYST Biocarbon Fuel cells Lignin-derived carbon Oxygen reduction reaction CHLORINE doping
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Sulfur-encapsulated in heteroatom-doped hierarchical porous carbon derived from goat hair for high performance lithium–sulfur batteries 被引量:12
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作者 Juan Ren Yibei Zhou +3 位作者 Huali Wu Fengyu Xie Chenggang Xu Dunmin Lin 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第3期121-131,共11页
Biomass-derived carbon materials have aroused widespread concern as host material of sulfur to enhance electrochemical performances for lithium–sulfur batteries. Herein, goat hair, as a low-cost and eco-friendly prec... Biomass-derived carbon materials have aroused widespread concern as host material of sulfur to enhance electrochemical performances for lithium–sulfur batteries. Herein, goat hair, as a low-cost and eco-friendly precursor, is employed to fabricate cauliflower-like in-situ nitrogen, oxygen and phosphorus tri-doped porous biomass carbon(NOPC) by a facile activation with H_3PO_4 and carbonization process.The morphology and microstructure of NOPC can be readily tuned by altering pyrolysis temperature. The as-prepared NOPC matrix material carbonized at 600 °C possesses 3D hierarchical porous structure, high specific surface area(535.352 m^2 g^(-1)), and appropriate pore size and pore size distribution. Encapsulating sulfur into the NOPC depends on a stem-melting technology as cathode materials of Li–S batteries. Due to the synergistic effect of special physical structure and inherent tri-doping of N, O and P, electrons and ions transfer and utilization of active sulfur in the materials are improved, and the shuttle behaviors of soluble lithium polysulfides are also mitigated. Consequently, the S/NOPC-600 composite exhibits excellent electrochemical performance, giving a high initial discharge capacity of 1185 mA h g^(-1) at 0.05 C and maintaining a relatively considerable capacity of 489 m A h g^(-1) at 0.2 C after 300 cycles. Our work shows that a promising candidate for cathode material of Li–S batteries can be synthesized using low-cost and renewable biomass materials by a facile process. 展开更多
关键词 Biomass-derived carbon materials GOAT HAIR Nitrogen Oxygen and phosphorus tri-doping LITHIUM SULFUR BATTERIES
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Carbide derived carbon electrode with natural graphite addition in magnesium electrolyte based cell for supercapacitor enhancements
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作者 Ramasamy Chandrasekaran Jesús Palma Marc Anderson 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第3期264-270,共7页
Herein,we have presented a supercapacitor based on carbide derived carbon(CDC) electrode with natural graphite(NG) addition.The capacitor was analyzed at 22°C by cyclic voltammetry,galvanostatic charge-discha... Herein,we have presented a supercapacitor based on carbide derived carbon(CDC) electrode with natural graphite(NG) addition.The capacitor was analyzed at 22°C by cyclic voltammetry,galvanostatic charge-discharge and impedance techniques using a 0.5 mol/L of magnesium(II)bis(trifluoro methanesulfonyl) imide(Mg TFSI) in ethylene carbonate-propylene carbonate(EC :PC = 1 :1,v/v) as electrolyte.The results conclude that the CDC cell enhancements have been proven by the composite electrode(5%–30% NG to CDC) especially on the cell efficiency and voltage i.e.,the CDC cell around 2.5 V limit was improved.An obtainable specific capacitance,real power and energy density are 15 F g-1,1.2 k W kg-1and 15 Wh kg-1,respectively. 展开更多
关键词 SUPERCAPACITOR carbide derived carbon magnesium imide organic electrolyte natural graphite
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Pseudo Constants for Methyl Red Sorption: A Rate Study of Received and Derived Activated Carbon
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作者 Adams U. Itodo Abdulrazak Abdulrahman +1 位作者 Abdullahi Usman Vincent C. Ugboaja 《Journal of Encapsulation and Adsorption Sciences》 2011年第4期57-64,共8页
This effluent remediation research on discoloration tends to disagree with the use of commercial activated carbon as received from manufacturers. Product specification and authentication is a key task to chemists and ... This effluent remediation research on discoloration tends to disagree with the use of commercial activated carbon as received from manufacturers. Product specification and authentication is a key task to chemists and scientist. Here, Batch kinetic studies via pseudo approximations treatments was adopted to to investigate the rate of Methyl Red (MR) dye solution uptake onto carbon animalis earlier received as Granulated Activated Carbon (GAC) and later formulated as Powdered Activated Carbon (PAC). The rate of dye uptake was studied with data fitted in to the Lagergren’s pseudo first and second order kinetic models. Justification by the R2 values (0.984) for GACgreater than 0.865 for PAC, low statistical error (SSE%) range of 1.065 - 2.310 and closeness between the experimented and calculated qe values all favored the second order kinetic model. The deviation of the line from the origin further showed that intra-particle transport is not the only rate limiting step. Generally the research supported the manufacturer’s choice of particle size (as GAC and not PAC) for the chosen adsorbate. 展开更多
关键词 Activated carbon PSEUDO CONSTANTS Methyl Red SORPTION derived RECEIVED
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MOF(ZM)/Potassium Citrate-Derived Composite Porous Carbon and Its Electrochemical Properties
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作者 Guoqing Zhang Pitao Wang +6 位作者 Chi Zhang Lili Wu Jing Yang Mingjian Zhang Zhong Ren Jianqiang Zhang Heming Luo 《Journal of Minerals and Materials Characterization and Engineering》 2021年第5期462-479,共18页
Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and ene... Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and energy storage, because of their unique structures. In this paper, we prepared a metal-organic framework [(<em>μ</em><sub>2</sub>-2-methylimidazolyl)<sub>12</sub>-Zn(ii)<sub>6</sub>-H<sub>18</sub>O<sub>10</sub>]<sub>n</sub>(ZM) with well-developed pores and high specific surface area of MOFs by the solution method. And MOF-derived porous carbon was prepared by the direct charring method in an argon atmosphere using a mixture of ZM, ZM and potassium citrate as carbon precursors. Characterization analysis revealed that the maximum specific surface area of ZMPC-800-1:15 was 2014.97 m<sup>2</sup><span style="white-space:nowrap;">&#8901;</span>g<sup><span style="white-space:nowrap;">&minus;</span>1</sup>, and the pore size structure was mainly mesoporous. At a current density of 1.0 A<span style="white-space:nowrap;">&#8901;</span>g<sup><span style="white-space:nowrap;">&minus;</span>1</sup> the specific capacitance of ZMC-800 and ZMPC-800-1:15 was 121.3 F<span style="white-space:nowrap;">&#8901;</span>g<sup><span style="white-space:nowrap;">&minus;</span>1</sup> and 226.6 F<span style="white-space:nowrap;">&#8901;</span>g<sup><span style="white-space:nowrap;">&minus;</span>1</sup>, respectively, with a substantial increase of 86.8%. The specific capacitance of ZMPC-800-1:15 decays to 168.8 F<span style="white-space:nowrap;">&#8901;</span>g<sup><span style="white-space:nowrap;">&minus;</span>1</sup>, with a decay rate of 25.5%, when the current density increases to 10.0 A<span style="white-space:nowrap;">&#8901;</span>g<sup><span style="white-space:nowrap;">&minus;</span>1</sup>. After 5000 constant current charge/ discharge cycles, the capacitance retention rate was still 96.41%. These results prove that the application of MOF-derived carbon materials in future supercapacitors is very promising. 展开更多
关键词 Metal-Organic Framework Room Temperature Solution Method derived Composite Porous carbon Electrochemical Performance SUPERCAPACITOR
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Activated Carbon Precursors Derived from Jute Fiber:Social,Eco­nomic and Environmental Development
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作者 Md.Touhidul Islam 《Non-Metallic Material Science》 2022年第2期49-57,共9页
Activated carbon fiber(ACF)is undoubtedly one of the most significant carbon nanocomposite materials to consider from the perspective of application in adsorption.Compared to other commercial porous storage materials,... Activated carbon fiber(ACF)is undoubtedly one of the most significant carbon nanocomposite materials to consider from the perspective of application in adsorption.Compared to other commercial porous storage materials,it offers many benefits.With a fiber-like shape and a clearly defined porosity structure,activated carbon fiber(ACF)is a potential microporous material.In general,synthetic carbon fiber(CF)can be used to commercially make ACF with the inclusion of an activation procedure.High packing density,outstanding volumetric capacity,rapid adsorption/desorption,and ease of handling are some of the unique properties of ACF.The production expenses of ACF are made up of fiber processing costs and activation costs,both of which are comparatively more expensive than those of other activated carbons.Recently,researchers have indicated that the manufacturing of ACF from less expensive precursors might be accomplished by preparing activated carbon(AC)from agricultural wastes.In comparison to synthetic ACF,there were fewer details and publicly accessible sources of information about these natural fiber derived ACF.The cost of processing fiber is higher and shaping fiber into the correct shape is challenging.In this study,social and environmental compliance,economic development,advantages of carbon fiber,and applications of carbon fiber are discussed. 展开更多
关键词 carbon fiber BIODEGRADABILITY Precursors derivATION
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Influence of pyrolysis temperature on structure and dielectric properties of polycarbosilane derived silicon carbide ceramic 被引量:2
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作者 丁冬海 周万城 +2 位作者 周璇 罗发 朱冬梅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2726-2729,共4页
β-SiC ceramic powders were obtained by pyrolyzing polycarbosilane in vacuum at 800-1200 °C. The β-SiC ceramic powders were characterized by TGA/DSC, XRD and Raman spectroscopy. The dielectric properties of β-S... β-SiC ceramic powders were obtained by pyrolyzing polycarbosilane in vacuum at 800-1200 °C. The β-SiC ceramic powders were characterized by TGA/DSC, XRD and Raman spectroscopy. The dielectric properties of β-SiC ceramic powders were investigated by measuring their complex permittivity by rectangle wave guide method in the frequency range of 8.2-18 GHz. The results show that both real part ε′ and imaginary part ε″ of complex permittivity increase with increasing pyrolysis temperature. The mechanism was proposed that order carbon formed at high temperature resulted in electron relaxation polarization and conductance loss, which contributes to the increase in complex permittivity. 展开更多
关键词 silicon carbide ceramic polycarbosilane derived SiC dielectric properties pyrolysis temperature free carbon complexpermittivity
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A Dual Wavelength Differential First Derivative Spectrophotometric Method for Identification and Determination of Carbon Monoxide Generated During the Microsomal Metabolism of Xenobiotics in vitro
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作者 徐宏祥 刘志强 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第2期51-56,共6页
A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and... A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and to determine CO formed during the microsomal metabolism of xenobiotics in vitro. The method can significantly eliminate the background interference in the assay media and increase the quantitative accuracy and the sensitivity. There is a good linear relationship between CO concentration in the range of 2~10 μmol·L 1 CO and the distance D between the first derivative peak at 415 nm amd valley at 426 nm with r=0.9999(n=5),the regression equation being C (mmol·L 1 )=17.6D 0.4, the detection limit lower than 0.1 μmol·L 1 CO. The average recoveries of CO from the assay system and the sample were 102.1%, RSD=2.9% (n=7) and 79.7%, RSD=6.8% (n=12),respectively. The RSD of within day was 4.4%(n=18),and the RSD of day to day was 6.1%(n=16). By this method, four trihaloanilines and one trihalobenzene were tested, the results showed that only 2,4,5 trifluoroaniline could be converted to CO by the incubation with rat hepatic microsomes, NADPH and oxygen, the ability of phenobarbital or dexamethasone to induce rat hepatic microsomes to catalyze CO formation was 3 or 8 times higher than that of the control. 展开更多
关键词 Dual wavelength differential first derivative spectrophotometry carbon monoxide Trifluoroaniline Drug metabolism Hepatic microsomes Cytochrome P 450
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Two-dimensional porous carbon derived from pollen with enlarged interlayer distance enhanced electrocatalytic oxidation of n-valeraldehyde to octane
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作者 Meichun Qin Chaolong Liu +1 位作者 Shouhen Xu Jianguo Tang 《Nano Research》 SCIE EI CSCD 2024年第5期3455-3461,共7页
Electrocatalytic n-valeraldehyde oxidation reaction was an inexpensive and eco-friendly method to control n-valeraldehyde contamination and produce high value-added octane.However,low-cost and readily available electr... Electrocatalytic n-valeraldehyde oxidation reaction was an inexpensive and eco-friendly method to control n-valeraldehyde contamination and produce high value-added octane.However,low-cost and readily available electrocatalysts with high current efficiency were urgently needed.Herein,two-dimensional porous carbon derived from pollen with enlarged interlayer distance was built by alkali activation method,applying in electrocatalytic n-valeraldehyde oxidation reaction.The enlarged interlayer distance was verified by X-ray diffraction(XRD)and high-angle annular dark-field scanning transmission electron microscope(HAADF-STEM).Electrocatalytic experiments consequences showed activated biomass derived carbon possessed a higher electrocatalytic activity and octane selectivity than unactivated catalyst.Systematic tests and in situ infrared experiments demonstrated that enlarged interlayer distance was positively correlated with specific surface area of catalysts,large specific surface area provided abundant absorption sites,facilitated the adsorption for n-valeraldehyde,and further promoted the transformation of n-valeraldehyde to octane.This work also provides a new avenue for creating high-performance electrocatalysts in terms of lattice engineering. 展开更多
关键词 biomass derived carbon lattice expansion high specific surface area upgrade of n-valeraldehyde
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Photo-induced Ag modulating carbon dots:Greatly improved fluorescent properties and derived sensing application
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作者 Yuwei Wang Ye Li +7 位作者 Guixiang Yang Xiaofeng Yang Chenglu Yan Huaqiao Peng Huiyong Wang Juan Du Baozhan Zheng Yong Guo 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期338-342,共5页
Carbon dots(CDs)have been attracted much attention and widely studied due to their excellent fluorescence(FL)properties,better biocompatibility and outstanding photo/chemical stability.However,the disadvantage of lowe... Carbon dots(CDs)have been attracted much attention and widely studied due to their excellent fluorescence(FL)properties,better biocompatibility and outstanding photo/chemical stability.However,the disadvantage of lower quantum yield(QY)still limits its wide application.Herein,we reported a novel and convenient strategy to prepare photo-induced Ag/CDs(p-Ag/CDs)by irradiating the mixed Ag+and hydrophobic CDs(h-CDs)acetone solution with ultraviolet(UV)light.The obtained p-Ag/CDs exhibit a greatly enhanced FL emission together with a blue shift(460 nm)than h-CDs(520 nm).The QY of p-Ag/CDs is measured to be 51.1%,which is 10.4 times higher than that of h-CDs(4.9%),indicating that photo-induced Ag modulation can effectively improve the optical properties of CDs.The mechanisms for the FL enhancement and blue shift of h-CDs are studied in detail.The results prove that the greatly enhanced FL emission is from the generated Ag nanoparticles(AgNPs)by UV light irradiation based on metal-enhanced fluorescence(MEF),and the increased oxygen-contained groups in this process lead to the blue shift in CDs fluorescence.Interestingly,the p-Ag/CDs exhibit higher sensitivity and selectivity for sulfide ions(S2-)detection than that of h-CDs,which have a lower response to S2-.This work not only offers a novel strategy to improve the FL properties of materials but also endows them with new functions and broadens their application fields. 展开更多
关键词 carbon dots Photo-induced Ag modulating Fluorescent enhancement High quantum yield derived sensing application Sulfide determination
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Metal Ions Extraction with Glucose Derivatives as Chelating Reagents in Supercritical Carbon Dioxide 被引量:3
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作者 Guo Chen YANG Hai Jian YANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第11期1489-1492,共4页
A series of glucose derivatives have been used as chelating reagents to extract metal ions in supercritical carbon dioxide. With perfluoro-l-octanesulfonic acid tetraethylammonium salt as additive, glucose derivatives... A series of glucose derivatives have been used as chelating reagents to extract metal ions in supercritical carbon dioxide. With perfluoro-l-octanesulfonic acid tetraethylammonium salt as additive, glucose derivatives were selective for Sr^2+ and Pb^2+ extraction in supercritical carbon dioxide. 展开更多
关键词 Supercritical carbon dioxide metal ions extraction glucose derivatives selectivity.
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Carbon-based derivatives from metal-organic frameworks as cathode hosts for Li–S batteries 被引量:7
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作者 Qingping Wu Xuejun Zhou +2 位作者 Jun Xu Fahai Cao Chilin Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第11期94-113,共20页
Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh... Lithium-sulfur batteries(Li–S batteries) are promising candidates for the next generation high-energy rechargeable Li batteries due to their high theoretical specific capacity(1672 m Ahg-1) and energy density(2500 Wh kg-1). The commercialization of Li–S batteries is impeded by several key challenges at cathode side, e.g. the insulating nature of sulfur and discharged products(Li2S 2 and Li2S), the solubility of long-chain polysulfides and volume variation of sulfur cathode upon cycling. Recently, the carbonbased derivatives from metal-organic frameworks(MOFs) has emerged talent in their utilization as cathode hosts for Li–S batteries. They are not only highly conductive and porous to enable the acceleration of Li +/e-transfer and accommodation of volumetric expansion of sulfur cathode during cycling, but also enriched by controllable chemical active sites to enable the adsorption of polysulfides and promotion of their conversion reaction kinetics. In this review, based on the types of MOFs(e.g. ZIF-8, ZIF-67, Prussian blue, Al-MOF, MOF-5, Cu-MOF, Ni-MOF), the synthetic methods, formation process and morphology, structural superiority of MOFs-derived carbon frameworks along with their electrochemical performance as cathode host in Li–S batteries are summarized and discussed. 展开更多
关键词 Lithium-sulfur BATTERIES carbon-based derivATIVES Metal-organic frame works CATHODE host
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Effect of Pyrolysis Temperature on the Electrical Behavior of Polymer-Derived SiOCN Ceramic
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作者 Yan Li Yuxi Yu +2 位作者 Haisheng San Qingkai Han Linan An 《Journal of Materials Science and Chemical Engineering》 2015年第10期9-16,共8页
The conductivity of polymer-derived SiOCN ceramics exhibited an Arrhenius dependence on pyrolysis temperature, with the activation energy of ~3.95 eV. The formation and structure change of the free carbon phase were d... The conductivity of polymer-derived SiOCN ceramics exhibited an Arrhenius dependence on pyrolysis temperature, with the activation energy of ~3.95 eV. The formation and structure change of the free carbon phase were detected by means of electron spin resonance spectroscopy and X-ray photoelectron spectroscopy. It reveals that the number of dangling bonds on the free carbon is increased as pyrolysis temperature increases, with the activation energy of ~3.87 eV. So it is demonstrated that the pyrolysis-temperature induced increase in the conductivity is mainly attributed to the increase of dangling on the graphite-like carbon. 展开更多
关键词 POLYMER derived SiOCN Ceremic Free carbon ACTIVATION ENERGY
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Three novel dendritic chitosan derivatives for inhibiting acid corrosion of petroleum pipelines
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作者 Guo-Dong Cui Yan-Ming Chen +7 位作者 Qi-Ming Zhang Zheng Wang Tian Tang Qing Zhao Yu Zhang Li-Feng Zhang Yuan-Qi Gu Yang-Sheng Liu 《Petroleum Science》 SCIE EI CAS CSCD 2023年第6期3918-3930,共13页
In the process of exploration and development of oil and gas fields, the acidic environment of oil reservoir, production and transport processes cause corrosion of pipelines and equipment, resulting in huge economic l... In the process of exploration and development of oil and gas fields, the acidic environment of oil reservoir, production and transport processes cause corrosion of pipelines and equipment, resulting in huge economic losses and production safety risks. Corrosion inhibitors were widely used in oil industry because of simple operation process and economical. In this study, three environmentally friendly corrosion inhibitors were synthesized based on the natural polysaccharide chitosan. Corrosion inhibition of three dendritic chitosan derivatives (We name them BH, CH and DH) on mild steel in 1 mol/L HCl solution with natural ventilation system was evaluated by weight loss experiment, electrochemical analysis and surface morphology characterization. The experimental results showed that when the three dendritic chitosan derivatives added in the corrosive medium were 500 mg L^(−1), the corrosion inhibition efficiencies were all more than 80%. Based on quantum chemical calculation, inhibition mechanisms of three dendritic chitosan derivatives were investigated according to molecular structures. The results showed that the benzene ring, Schiff base and N atom contained in the molecule were the active centers of electron exchange, which were more likely to form a film on the carbon steel surface, thereby slowing or inhibiting corrosion. The results also predicted the corrosion inhibition effect BH > DH > CH, which was consistent with the experimental conclusion. 展开更多
关键词 Chitosan derivatives Corrosion inhibitors carbon steel Acid inhibition Efficient and environmental
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中国大气田烷烃气碳同位素组成的若干特征 被引量:1
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作者 戴金星 倪云燕 +4 位作者 龚德瑜 黄士鹏 刘全有 洪峰 张延玲 《石油勘探与开发》 EI CAS CSCD 北大核心 2024年第2期223-233,共11页
勘探开发大气田是一个国家快速发展天然气工业的重要途径。1991年至2020年,中国新探明大气田68个,促进2020年产气1925×10^(8)m^(3),成为世界第4产气大国。基于中国70个大气田的1696个气样组分和烷烃气碳同位素组成数据,获得中国大... 勘探开发大气田是一个国家快速发展天然气工业的重要途径。1991年至2020年,中国新探明大气田68个,促进2020年产气1925×10^(8)m^(3),成为世界第4产气大国。基于中国70个大气田的1696个气样组分和烷烃气碳同位素组成数据,获得中国大气田烷烃气碳同位素组成特征:①δ^(13)C_(1)、δ^(13)C_(2)、δ^(13)C_(3)和δ^(13)C_(4)的最轻值和平均值,随分子中碳数逐增而变重,而δ^(13)C_(1)、δ^(13)C_(2)、δ^(13)C_(3)和δ^(13)C_(4)的最重值,随分子中碳数逐增而变轻。②中国大气田δ^(13)C_(1)值的分布区间为−71.2‰~−11.4‰,其中生物气δ^(13)C_(1)值的分布区间为−71.2‰~−56.4‰;油型气δ^(13)C_(1)值的分布区间为−54.4‰~−21.6‰;煤成气δ^(13)C_(1)值的分布区间为−49.3‰~−18.9‰;无机成因气δ^(13)C_(1)值的分布区间为−35.6‰~−11.4‰;根据这些数据编制了中国大气田的δ^(13)C_(1)值尺图。③中国天然气δ^(13)C_(1)值的分布区间为−107.1‰~−8.9‰,其中生物气δ^(13)C_(1)值为−107.1‰~−55.1‰;油型气δ^(13)C^(1)值为−54.4‰~−21.6‰;煤成气δ^(13)C_(1)值为−49.3‰~−13.3‰;无机成因气δ13C1值为−36.2‰~−8.9‰;根据上述数据编制了中国天然气的δ^(13)C_(1)值尺图。 展开更多
关键词 中国 大气田 生物气 油型气 煤成气 无机成因气 烷烃气 碳同位素组成 δ_(13)C^(1)值尺
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