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Reliability analysis of carbon fiber rod-reinforced umbilical cable under tension using an improved sampling method
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作者 Yu Zhang Hong-Yu Zhang +2 位作者 Ran Xia Si-Ao Jiang Fang Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2769-2778,共10页
The umbilical cable is a vital component of subsea production systems that provide power,chemical agents,control signals et al.,and its requirement for reliability is exceedingly high.However,as the umbilical cable is... The umbilical cable is a vital component of subsea production systems that provide power,chemical agents,control signals et al.,and its requirement for reliability is exceedingly high.However,as the umbilical cable is a composite structure comprising multiple functional units,the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency.In this paper,the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed.The global dynamic analytical model is first established to determine the maximum tension load,then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM).Based on the mechanical analytical model,the reliability of umbilical cable under tension load is studied using response surface method(RSM)and Monte Carlo method.During the calculation process,a new tangent plane sampling method to calculate the response surface function(RSF)is proposed in this paper,which could make sampling points faster come close to the RSF curve,and it is proved that the calculation efficiency increases about 33%comparing with traditional method. 展开更多
关键词 Umbilical cable carbon fiber rod Failure analysis Response surface method Reliability
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Synthesis and Characterization of Hollow Strontium Carbonate Pompons by Composite Soft Template Method
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作者 LI Bibo DONG Xiufang +4 位作者 LI Yu SONG Jian XIE Wuxi ZHANG Wei LIU Yunfei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1434-1439,共6页
The hollow strontium carbonate pompons was synthesized for the first time by a controlled reaction precipitation method with sodium dodecyl benzene sulfonate(SDBS)and polyvinyl pyrrolidone(PVP)work together as templat... The hollow strontium carbonate pompons was synthesized for the first time by a controlled reaction precipitation method with sodium dodecyl benzene sulfonate(SDBS)and polyvinyl pyrrolidone(PVP)work together as template.The sampled particles were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM),nitrogen adsorption-desorption measurement,X-ray diffraction(XRD),Energy dispersive X-Ray spectroscopy(EDX),Fourier transform infrared spectroscopy(FTIR),Thermogravimetric analysis and differential scanning calorimetry(TGA-DSC),etc.It is shown that the assynthesized hollow strontium carbonate pompons with the size of about 2μm consist of flake-like particles under the optimal reaction conditions.The formation mechanism of hollow strontium carbonate pompons was preliminarily explored. 展开更多
关键词 strontium carbonate hollow structure pompons composite soft template method
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The preparation and properties of N-doped carbon materials and their use for sodium storage
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作者 YUAN Ren-lu HOU Ruo-yang +4 位作者 SHANG Lei LIU Xue-wei LI Ang CHEN Xiao-hong SONG Huai-he 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期770-795,共26页
Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applicatio... Defect engineering by heteroatom doping gives carbon materials some new characteristics such as a different electronic structure and a high electrochemical activity,making them suitable for high-performance applications.N-doping has been widely investigated because of its similar atom radius to carbon,high electronegativity as well as many different configurations.We summarize the preparation methods and properties of N-doped carbon materials,and discuss their possible use in sodium ion storage.The relationships between N content/configuration and crystallinity,electronic conductivity,wettability,chemical reactivity as well as sodium ion storage performance are discussed. 展开更多
关键词 N-doped carbon material N configuration Preparation method Performance Sodium storage
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Facile preparation of Fe/N-based biomass porous carbon composite towards enhancing the thermal decomposition of DAP-4
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作者 Er-hai An Xiao-xia Li +5 位作者 Cun-juan Yu Ying-xin Tan Zi-jun Fan Qing-xia Li Peng Deng Xiong Cao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期288-294,共7页
Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular... Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was studied.Biomass porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N precursors.Fe/Np Carbon was prepared simply by the high-temperature carbonization method.It was found that it showed the inherent catalysis properties for thermal decomposition of DAP-4.The heat release of DAP-4/Fe/N-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/N-p Carbon-0.The decomposition temperature peak of DAP-4 at the presence of Fe/N-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/N-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/mol.The possible catalytic decomposition mechanism of DAP-4 with Fe/N-p Carbon was proposed. 展开更多
关键词 Biomass materials Porous carbon DAP-4 Thermal decomposition Facile method
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The potassium storage performance of carbon nanosheets derived from heavy oils
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作者 ZHAO Qing-shan LIU Qin-lian +6 位作者 LI Yi-wen JI Tian YAO Yu-yue ZHAO Yi-kun DENG Wei HU Han WU Ming-bo 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期1003-1014,共12页
As by-products of petroleum refining,heavy oils are characterized by a high carbon content,low cost and great variability,making them competitive precursors for the anodes of potassium ion batteries(PIBs).However,the ... As by-products of petroleum refining,heavy oils are characterized by a high carbon content,low cost and great variability,making them competitive precursors for the anodes of potassium ion batteries(PIBs).However,the relationship between heavy oil composition and potassium storage performance remains unclear.Using heavy oils containing distinct chemical groups as the carbon source,namely fluid catalytic cracking slurry(FCCS),petroleum asphalt(PA)and deoiled asphalt(DOA),three carbon nanosheets(CNS)were prepared through a molten salt method,and used as the anodes for PIBs.The composition of the heavy oil determines the lamellar thicknesses,sp3-C/sp2-C ratio and defect concentration,thereby affecting the potassium storage performance.The high content of aromatic hydrocarbons and moderate amount of heavy component moieties in FCCS produce carbon nanosheets(CNS-FCCS)that have a smaller layer thickness,larger interlayer spacing(0.372 nm),and increased number of folds than in CNS derived from the other three precursors.These features give it faster charge/ion transfer,more potassium storage sites and better reaction kinetics.CNS-FCCS has a remarkable K^(+)storage capacity(248.7 mAh g^(-1) after 100 cycles at 0.1 A g^(-1)),long cycle lifespan(190.8 mAh g^(-1) after 800 cycles at 1.0 A g^(-1))and excellent rate capability,ranking it among the best materials for this application.This work sheds light on the influence of heavy oil composition on carbon structure and electrochemical performance,and provides guidance for the design and development of advanced heavy oil-derived carbon electrodes for PIBs. 展开更多
关键词 Heavy oils carbon nanosheets Molten salt method Four-component composition Potassium-ion batteries
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Unveiling the chemistry behind the electrolytic production of hydrogen peroxide by oxygenated carbon
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作者 Pan Xiang Kunshang Yang +6 位作者 Qihao Yang Yang Gao Wenwen Xu Zhiyi Lu Liang Chen Zhiming Wang Ziqi Tian 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期49-58,共10页
Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction reaction.The nature of the active functional group and u... Oxygenated carbon materials exhibit outstanding electrocatalytic performance in the production of hydrogen peroxide(H2O2)through a two-electron oxygen reduction reaction.The nature of the active functional group and underlying reaction mechanism,however,remain unclear.Here,a comprehensive workflow was established to identify the active sites from the numerous possible structures.The common hydroxyl group at the notched edge demonstrates a key role in the two-electron process.The local chemical environment weakens the binding of OOH intermediate to substrate while enhancing interaction with solution,thereby promoting the H_(2)O_(2)production.With increasing pH,the intramolecular hydrogen bond between OOH intermediate and hydroxyl decreases,facilitating OOH desorption.Furthermore,the rise in selectivity with increasing potential stems from the suppression of the four-electron process.The active site was further validated through experiments.Guided by theoretical understanding,optimal performance was achieved with high selectivity(>95%)and current density(2.06 mA/cm^(2))in experiment. 展开更多
关键词 First-principles calculation Oxygen reductionreaction Hydrogen peroxide production Fixed-potential method Oxygenated carbon materials
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Toward Establishing a Low-cost UAV Coordinated Carbon Observation Network(LUCCN):First Integrated Campaign in China
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作者 Dongxu YANG Tonghui ZHAO +11 位作者 Lu YAO Dong GUO Meng FAN Xiaoyu REN Mingge LI Kai WU Jing WANG Zhaonan CAI Sisi WANG Jiaxu GUO Liangfu CHEN Yi LIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第1期1-7,共7页
In this study,we introduce our newly developed measurement-fed-perception self-adaption Low-cost UAV Coordinated Carbon Observation Network(LUCCN)prototype.The LUCCN primarily consists of two categories of instruments... In this study,we introduce our newly developed measurement-fed-perception self-adaption Low-cost UAV Coordinated Carbon Observation Network(LUCCN)prototype.The LUCCN primarily consists of two categories of instruments,including ground-based and UAV-based in-situ measurement.We use the GMP343,a low-cost non-dispersive infrared sensor,in both ground-based and UAV-based instruments.The first integrated measurement campaign took place in Shenzhen,China,4 May 2023.During the campaign,we found that LUCCN’s UAV component presented significant data-collecting advantages over its ground-based counterpart owing to the relatively high altitudes of the point emission sources,which was especially obvious at a gas power plant in Shenzhen.The emission flux was calculated by a crosssectional flux(CSF)method,the results of which differed from the Open-Data Inventory for Anthropogenic Carbon dioxide(ODIAC).The CSF result was slightly larger than others because of the low sampling rate of the whole emission cross section.The LUCCN system will be applied in future carbon monitoring campaigns to increase the spatiotemporal coverage of carbon emission information,especially in scenarios involving the detection of smaller-scale,rapidly varying sources and sinks. 展开更多
关键词 CO_(2) measurement networks power station carbon emission cross-sectional flux method
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Self-templating synthesis of biomass-based porous carbon nanotubes for energy storage and catalytic degradation applications
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作者 Manman Xu Shiqi Fu +7 位作者 Yukai Wen Wei Li Qiongfang Zhuo Haida Zhu Zhikeng Zheng Yuwen Chen Anqi Wang Kai Yan 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期584-595,共12页
Dwindling energy sources and a worsening environment are huge global problems,and biomass wastes are an under-exploited source of material for both energy and material generation.Herein,self-template decoction dregs o... Dwindling energy sources and a worsening environment are huge global problems,and biomass wastes are an under-exploited source of material for both energy and material generation.Herein,self-template decoction dregs of Ganoderma lucidum-derived porous carbon nanotubes(ST-DDLGCs)were synthesized via a facile and scalable strategy in response to these challenges.ST-DDLGCs exhibited a large surface area(1731.51 m^(2)g^(-1))and high pore volume(0.76 cm^(3)g^(-1)),due to the interlacing tubular structures of precursors and extra-hierarchical porous structures on tube walls.In the ST-DDLGC/PMS system,the degradation efficiency of capecitabine(CAP)reached~97.3%within 120 min.Moreover,ST-DDLGCs displayed high catalytic activity over a wide pH range of 3–9,and strong anti-interference to these typical and ubiquitous anions in wastewater and natural water bodies(i.e.,H_(2)PO_(4)^(-),NO_(3)^(-),Cl^(-) and HCO_(3)^(-)),in which a ^(1)O_(2)-dominated oxidation was identified and non-radical mechanisms were deduced.Additionally,ST-DDLGC-based coin-type symmetrical supercapacitors exhibited outstanding electrochemical performance,with specific capacitances of up to 328.1 F g^(-1)at 0.5 A g^(-1),and cycling stability of up to 98.6%after 10,000 cycles at a current density of 2 A g^(-1).The superior properties of ST-DDLGCs could be attributed to the unique porous tubular structure,which facilitated mass transfer and presented numerous active sites.The results highlight ST-DDLGCs as a potential candidate for constructing inexpensive and advanced environmentally functional materials and energy storage devices. 展开更多
关键词 Ganoderma lucidum residue Porous carbon nanotubes Self-template method Wastewater treatment Supercapacitor electrode
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High sensitivity detection of baicalein by N,S co⁃doped carbon dots and their application in biofluids
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作者 FAN Junmei LIU Wei +5 位作者 ZHU Ruitao QIN Chenxi LEI Xiaoling WANG Haotian WANG Jiao HAN Hongfei 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第10期2009-2020,共12页
In this work,p⁃phenylenediamine and L⁃cysteine were used as raw materials,and water⁃soluble N,S co⁃doped carbon dots(N,S⁃CDs)with excellent performance were prepared through a one⁃step solvothermal method.The morpholo... In this work,p⁃phenylenediamine and L⁃cysteine were used as raw materials,and water⁃soluble N,S co⁃doped carbon dots(N,S⁃CDs)with excellent performance were prepared through a one⁃step solvothermal method.The morphology and structure of N,S⁃CDs were characterized by transmission electron microscope,X⁃ray diffrac⁃tion,Fourier transform infrared spectroscopy,and X⁃ray photoelectron spectroscopy,and the basic photophysical properties were investigated via UV⁃Vis absorption spectra and fluorescence spectra.Meanwhile,the N,S⁃CDs have excellent luminescence stability with pH,ionic strength,radiation time,and storage time.Experimental results illus⁃trated the present sensor platform exhibited high sensitivity and selectivity in response to baicalein with a detection limit of 85 nmol·L-1.The quenching mechanism is proved to be the inner filter effect.In addition,this sensor can also detect baicalein in biofluids(serum and urine)with good accuracy and reproducibility. 展开更多
关键词 N S⁃carbon dots solvothermal method BAICALEIN fluorescent sensor
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Structural and microwave absorption properties of CoFe_(2)O_(4)/residual carbon composites
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作者 Yuanchun Zhang Shengtao Gao +3 位作者 Xingzhao Zhang Dacheng Ma Chuanlei Zhu Jun He 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期221-232,共12页
Electromagnetic interference,which necessitates the rapid advancement of substances with exceptional capabilities for bsorbing electromagnetic waves,is of urgent concern in contemporary society.In this work,CoFe_(2)O_... Electromagnetic interference,which necessitates the rapid advancement of substances with exceptional capabilities for bsorbing electromagnetic waves,is of urgent concern in contemporary society.In this work,CoFe_(2)O_(4)/residual carbon from coal gasification fine slag(CFO/RC)composites were created using a novel hydrothermal method.Various mechanisms for microwave absorption,including conductive loss,natural resonance,interfacial dipole polarization,and magnetic flux loss,are involved in these composites.Consequently,compared with pure residual carbon materials,this composite offers superior capabilities in microwave absorption.At 7.76GHz,the CFO/RC-2 composite achieves an impressive minimum reflection loss(RL_(min))of-43.99 dB with a thickness of 2.44 mm.Moreover,CFO/RC-3 demonstrates an effective absorption bandwidth(EAB)of up to 4.16 GHz,accompanied by a thickness of 1.18mm.This study revealed the remarkable capability of the composite to diminish electromagnetic waves,providing a new generation method for microwave absorbing materials of superior quality. 展开更多
关键词 coal gasification slag residual carbon hydrothermal method microwave absorption CoFe_(2)O_(4)
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Effect of preparation methods on the adsorption property of municipal solid waste-based carbon materials 被引量:1
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作者 宋敏 唐心红 +1 位作者 唐美 卫月星 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期208-214,共7页
Three different preparation methods including steam physical activation, catalytic carbonation and KOH chemical activation methods were used to prepare municipal solid waste- based carbon materials. The methylene blue... Three different preparation methods including steam physical activation, catalytic carbonation and KOH chemical activation methods were used to prepare municipal solid waste- based carbon materials. The methylene blue (MB) adsorption value was applied to evaluate the adsorption capabilities of the prepared carbon materials. The effects of preparation methods on adsorption capability and yield of products were investigated. The yield of carbon materials with the catalytic carbonation method is the highest, and the KOH activation method is the second level. Considering the adsorption performance, the KOH activation method is much more favorable. Among the different components of municipal solid waste-based carbon materials, the adsorption properties of the single component of paperboard, the double components of tire and paperboard, the triple components of tire, paperboard and polyvinyl chloride (PVC), and the multi-component mixtures are better than those of other single-, double-, triple- and multi-component mixtures, respectively. 展开更多
关键词 PYROLYSIS preparation methods WASTE ADSORPTION activated carbon
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Principles and Methods for Construction of Lowcarbon Landscape Architecture
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作者 李芸 李静 张浪 《Journal of Landscape Research》 2011年第3期4-6,11,共4页
After illustrating history of low-carbon theory and concept of low-carbon economy,the paper had indentified connotation and principles of low-carbon landscape architecture,pointed out that construction of low-carbon l... After illustrating history of low-carbon theory and concept of low-carbon economy,the paper had indentified connotation and principles of low-carbon landscape architecture,pointed out that construction of low-carbon landscape architecture should follow principles of "site respect,natural power,landscape heterogeneity and nature manifestation".Furthermore,it discussed methods for construction of low-carbon landscape architecture,highlighting rainwater reserve utilization,green landscape structure,effluent purification circulation,architectural materials selection and carbon sink increase by plants.Low-carbon urban landscaping concept and technology provided a new way of thinking for landscaping construction and they were also the urgent needs for construction of low-carbon city. 展开更多
关键词 Low-carbon Low-carbon LANDSCAPE ARCHITECTURE PRINCIPLES and methodS
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A new method of formation evaluation for fractured and caved carbonate reservoirs:A case study from the Lundong area,Tarim Basin,China 被引量:7
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作者 Yang Haijun Sam Zandong Sun +4 位作者 Cai Lulu Xiao Youjun WangHaiyang Luo Chunshu Hu Hongru 《Petroleum Science》 SCIE CAS CSCD 2011年第4期446-454,共9页
The carbonate reservoirs in the Tarim Basin are characterized by low matrix-porosity,heterogeneity and anisotropy,which make it difficult to predict and evaluate these reservoirs.The reservoir formations in Lundong ar... The carbonate reservoirs in the Tarim Basin are characterized by low matrix-porosity,heterogeneity and anisotropy,which make it difficult to predict and evaluate these reservoirs.The reservoir formations in Lundong area experienced a series of diagenesis and tectonic evolution stages.And secondary storage spaces such as fractures and dissolution caves were developed while nearly all the primary pores have disappeared.Based on a summary of different types of storage spaces and their responses in conventional logs,FMI and full waveform sonic logs which are sensitive to different reservoirs,the comprehensive probability index (CPI) method is applied to evaluating the reservoirs and a standard of reservoir classification is established.By comparing the evaluation results with actual welllogging results,the method has proven to be practical for formation evaluation of carbonate reservoirs,especially for the fractured carbonate reservoirs.In reservoir fluid identification,the multivariate stepwise discriminant analysis (MSDA) method is introduced.Combining the CPI method and MSDA method,comprehensive formation evaluation has been performed for fractured and caved carbonate reservoirs in the Tarim Basin.Additionally,on the basis of secondary pore inversion results,another new method of formation evaluation is also proposed in the discussion part of this paper.Through detailed application result analysis,the method shows a promising capability for formation evaluation of complex carbonate reservoirs dominated by various secondary pores such as holes,caves,and cracks. 展开更多
关键词 carbonate reservoir formation evaluation comprehensive probability index method discriminant analysis Tarim Basin
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A review of development methods and EOR technologies for carbonate reservoirs 被引量:14
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作者 Zheng-Xiao Xu Song-Yan Li +3 位作者 Bin-Fei Li Dan-Qi Chen Zhong-Yun Liu Zhao-Min Li 《Petroleum Science》 SCIE CAS CSCD 2020年第4期990-1013,共24页
Carbonate reservoirs worldwide are complex in structure,diverse in form,and highly heterogeneous.Based on these characteristics,the reservoir stimulation technologies and fluid flow characteristics of carbonate reserv... Carbonate reservoirs worldwide are complex in structure,diverse in form,and highly heterogeneous.Based on these characteristics,the reservoir stimulation technologies and fluid flow characteristics of carbonate reservoirs are briefly described in this study.The development methods and EOR technologies of carbonate reservoirs are systematically summarized,the relevant mechanisms are analyzed,and the application status of oil fields is catalogued.The challenges in the development of carbonate reservoirs are discussed,and future research directions are explored.In the current development processes of carbonate reservoirs,water flooding and gas flooding remain the primary means but are often prone to channeling problems.Chemical flooding is an effective method of tertiary oil recovery,but the harsh formation conditions require high-performance chemical agents.The application of emerging technologies can enhance the oil recovery efficiency and environmental friendliness to a certain extent,which is welcome in hard-to-recover areas such as heavy oil reservoirs,but the economic cost is often high.In future research on EOR technologies,flow field control and flow channel plugging will be the potential directions of traditional development methods,and the application of nanoparticles will revolutionize the chemical EOR methods.On the basis of diversified reservoir stimulation,combined with a variety of modern data processing schemes,multichannel EOR technologies are being developed to realize the systematic,intelligent,and cost-effective development of carbonate reservoirs. 展开更多
关键词 carbonate reservoir Reservoir stimulation Flow characteristic Development method EOR technology
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Direct Synthesis of Diphenyl Carbonate with Heterogeneous Catalyst and Optimal Synthesis Conditions of the Support Prepared by Sol-gel Method 被引量:10
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作者 郭红霞 陈红萍 +3 位作者 梁英华 芮玉兰 吕敬德 付占达 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第2期223-227,共5页
The support of catalyst for the direct synthesis of diphenyl carbonate (DPC) by heterogeneous catalytic reaction was prepared by the sol-gel method. Compared with activated charcoal, molecular sieve, porous ceramics... The support of catalyst for the direct synthesis of diphenyl carbonate (DPC) by heterogeneous catalytic reaction was prepared by the sol-gel method. Compared with activated charcoal, molecular sieve, porous ceramics, hopcalite, the support prepared by the sol-gel method has higher activity. The characterization of the support by X-ray diffraction (XRD) and transmission electron microscope (TEM) show that the mare crystal phase is Co2MnO4 and the average particle diameter is about 40 nm. The optimum conditions for synthesis of the support were determined by orthogonal experiments, which indicate that the proportion of Cu, Mn, and Co is the first important factor influencing the yield and selectivity of DPC. Temperature of calcination is the second one. The optimum conditions are: molar proportion of Cu, Mn, and Co being 1 : 1 : 1, temperature of calcination 700℃, drying at 100~C, temperature of water bath 85~C. The yield and selectivity of DPC in the process can reach 38% and 99% in the batch operation, respectively. The copper cobalt manganese mixed oxides chosen as the support contribute more to the high catalytic activity than the sol-gel method. 展开更多
关键词 diphenyl carbonate heterogeneous catalyst sol-gel method optimum condition
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Thermodynamic analysis of combined reforming process using Gibbs energy minimization method: In view of solid carbon formation 被引量:5
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作者 Behzad Nematollahi Mehran Rezaei +1 位作者 Ebrahim Nemati Lay Majid Khajenoori 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第6期694-702,共9页
Thermodynamic analysis was applied to study combined partial oxidation and carbon dioxide reforming of methane in view of carbon formation. The equilibrium calculations employing the Gibbs energy minimization were per... Thermodynamic analysis was applied to study combined partial oxidation and carbon dioxide reforming of methane in view of carbon formation. The equilibrium calculations employing the Gibbs energy minimization were performed upon wide ranges of pressure (1-25 atm), temperature (600-1300 K), carbon dioxide to methane ratio (0-2) and oxygen to methane ratio (0-1). The thermodynamic results were compared with the results obtained over a Ru supported catalyst. The results revealed that by increasing the reaction pressure methane conversion decreased. Also it was found that the atmospheric pressure is the preferable pressure for both dry reforming and partial oxidation of methane and increasing the temperature caused increases in both activity of carbon and conversion of methane. The results clearly showed that the addition of O2 to the feed mixture could lead to a reduction of carbon deposition. 展开更多
关键词 combined reforming carbon deposition chemical equilibrium Gibbs energy minimization method thermodynamic analysis
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Carbon matrix effects on the micro-structure and performance of Pt nanowire cathode prepared by decal transfer method 被引量:4
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作者 Zhaoxu Wei An He +1 位作者 Kaihua Su Sheng Sui 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第2期213-218,共6页
High performance cathode for polymer electrolyte membrane fuel cell was prepared by depositing Pt nanowires in a carbon matrix coated on a substrate, and using decal transfer method to fabricate the membrane electrode... High performance cathode for polymer electrolyte membrane fuel cell was prepared by depositing Pt nanowires in a carbon matrix coated on a substrate, and using decal transfer method to fabricate the membrane electrode assembly. The effects of carbon and ionomer contents on the electrode micro-structure and fuel cell performance are investigated by physical characterization and single cell testing. The Pt nanowires are gradient distributed across the cathode thickness, and more Pt exists near the membrane. Both the carbon and ionomer contents can affect the Pt nanowires distribution and aggregation. In addition, the carbon loading dominates the transport distance of gas and proton, and the ionomer content affects the triple phase boundaries and porosity in the cathode. The optimal structure of Pt nanowire cathode is obtained at 0.10 mg·cm^-2 carbon loading and 10 wt% ionomer. 展开更多
关键词 Pt nanowire carbon matrix IONOMER decal transfer method polymer electrolyte membrane fuel cell
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Preparation and CO conversion activity of ceria nanotubes by carbon nanotubes templating method 被引量:3
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作者 方建慧 曹志源 +3 位作者 张登松 沈霞 丁伟中 施利毅 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期153-157,共5页
Ceria nanotubes with high CO conversion activity by means of carbon nanotubes as removable templates in the simple liquid phase process were fabricated under moderate conditions. The pristine CNTs were first pretreate... Ceria nanotubes with high CO conversion activity by means of carbon nanotubes as removable templates in the simple liquid phase process were fabricated under moderate conditions. The pristine CNTs were first pretreated by refluxing in a 30% nitric acid solution at 140 ℃ for 24 h, then dispersed in an ethanolic Ce(NO3)3.6H2O solution with ultrasonic radiation at room temperature for 1 h. Under vigorous stirring, NaOH solution was added drop by drop into the above ethanolic solution until the pH value was 10. The product was collected and repeatedly washed with ethanol and on drying at 60 ℃, the CeO2/CNT composites were obtained. Then, the as-prepared composites were heated at 450 ℃ in an air atmosphere for 30 min to remove CNTs. The ceria nanotubes were characterized by X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM), and X-Ray Photoelectron Spectrum (XPS). The results showed that the ceria nanotubes were polycrystalline face-centered cubic phase and were composed of lots of dense cefia nanoparficles. The diameter of cefia nanotubes was about 40-50 nm. Catalytic activity of the product for CO oxidation was carded out at the region of 30-300 ℃ in a U-shaped quartz reactor with feeding about 0.15 g of the catalyst, which was loaded on Al2O3 carder. The inlet gas composition was 1.0% CO and 28% O2 with N2 as balance, and the rate of flow was kept at 40 ml/min. The catalytic products were analyzed by gas chromatography. The as-repared CeO2 nanotubes showed higher CO oxidation activity, which indicated that the morphology of ceria products affected the catalytic performance. The ceria nanotubes supported on Al2O3 demonstrated that conversion temperature for CO oxidation to CO2 was lower than that for bulk catalysts. 展开更多
关键词 ceria nanotube CO oxidation carbon nanotube templating method rare earths
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COMPARISON OF HTC METHOD AND UV/PERSULPHATE METHOD TO DETERMINE COLLOIDAL ORGANIC CARBON IN SEAWATER 被引量:2
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作者 王江涛 赵卫红 +1 位作者 谭丽菊 张正斌 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2000年第1期80-84,共5页
The application of cross flow ultrafiltration(CFF) techniques to separate colloidal organic carbon(COC) from truly dissolved organic carbon(TDOC) was investigated; COC and TDOC were determined by the high temperature ... The application of cross flow ultrafiltration(CFF) techniques to separate colloidal organic carbon(COC) from truly dissolved organic carbon(TDOC) was investigated; COC and TDOC were determined by the high temperature combustion method(HTC) and UV/persulphate method. It was found that CFF can quantitatively separate COC from seawater. The determination results by the HTC and UV/persulphate method for COC and TDOC showed little difference, which suggested that the oxidation efficiency of the two methods are identical. Colloidal particles have no remarkable influence on the oxidation efficiency of the UV/persulphate method. 展开更多
关键词 cross flow ULTRAFILTRATION COLLOIDAL organic carbon high temperature combustion method UV/persulphate method
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Effect of Different Irrigation Methods on Dissolved Organic Carbon and Microbial Biomass Carbon in the Greenhouse Soil 被引量:3
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作者 HAN Lin,ZHANG Yu-long,JIN Shuo,WANG Jiao,WEI Yan-yan,CUI Ning and WEI Wei College of Land and Environmental Sciences,Shenyang Agricultural University/Liaoning Key Laboratory of Agricultural Resources and Environment,Shenyang 110161,P.R.China 《Agricultural Sciences in China》 CSCD 2010年第8期1175-1182,共8页
The objective of this study was to investigate the contents and distribution of dissolved organic carbon (DOC) and microbial biomass carbon (MBC) at 0-100 cm soil depth under three irrigation treatments, viz., sub... The objective of this study was to investigate the contents and distribution of dissolved organic carbon (DOC) and microbial biomass carbon (MBC) at 0-100 cm soil depth under three irrigation treatments, viz., subsurface, drip and furrow irrigation in the greenhouse soil. The soil samples were collected at different depths (0-100 cm), and the contents of soil total organic carbon (TOC), DOC and MBC were analysed. The experiment was conducted for 10 yr, during which period the application of fertilizers and crop management practices were kept identical. The results showed that the contents of TOC, DOC and MBC were significantly affected by different irrigation regimes, decreased with the increase of soil depth. TOC at 0-10 and 80-100 cm soil depths followed the order of furrow irrigation 〉 subsurface irrigation 〉 drip irrigation, whereas at the depth of 10-80 cm followed the order of subsurface irrigation 〉 furrow irrigation 〉 drip irrigation. DOC and MBC contents at 0-100 cm soil depths followed the order of furrow irrigation 〉 drip irrigation 〉 subsurface irrigation, and drip irrigation 〉 furrow irrigation 〉 subsurface irrigation, respectively. The ratios of DOC and MBC to TOC accounted for 4.98-12.87% and 1.48-2.82%, respectively, which were the highest in the drip irrigation treatment, followed were in the furrow irrigation treatment, and the lowest in subsurface irrigation treatment. There were significant positive correlations among the contents of DOC, MBC and TOC in all irrigation treatments. The furrow irrigation facilitated the accumulation of TOC and DOC, while drip irrigation increased the MBC. The content of TOC and the ratios of DOC to TOC were the lowest in subsurface irrigation treatment. 展开更多
关键词 GREENHOUSE irrigation methods total organic carbon dissolved organic carbon microbial biomass carbon
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