检索结果-南通市图书馆

Infiltration of Ce0.8Gd0.2O1.9 nanoparticles on Sr2Fe1.5Mo0.5O6-δ cathode for CO2 electroreduction in solid oxide electrolysis cell

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2019年第8期28卷 71-78,I0004页

作者： Houfu Lv Yingjie Zhou Xiaomin Zhang Yuefeng Song Qingxue Liu Guoxiong Wang Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian 116023 Liaoning China University of Chinese Academy of Sciences Beijing 100039 China

solid oxide electrolysis cell(SOEC) can electrochemically convert CO2 to CO at the gas-solid interface with a high current density and Faradaic efficiency, which has attracted increasing attentions in recent years.Exploring efficient catalyst for electrochemical CO2 reduction reaction(CO2 RR) at the cathode is a grand challenge for the research and development of SOEC. Sr2Fe1.5Mo0.5O6-δ(SFM) is one kind of promising cathode materials for SOEC, but suffers from insufficient activity for CO2 RR. Herein, Gd0.2Ce0.8O1.9(GDC)nanoparticles were infiltrated onto the SFM surface to construct a composite GDC-SFM cathode and improve the CO2 RR performance in SOEC. The current density over the GDC infiltrated SFM cathode with a GDC loading of 12.8 wt% reaches 0.446 A cm-2 at 1.6 V and 800 °C, which is much higher than that over the SFM cathode(0.283 A cm-2). Temperature-programmed desorption of CO2 measurements suggest that the infiltration of GDC nanoparticles significantly increases the density of surface active sites and three phase boundaries(TPBs), which are beneficial for CO2 adsorption and subsequent conversion. Electrochemical impedance spectroscopy results indicate that the polarization resistance of 12.8 wt% GDCSFM cathode was obviously decreased from 0.46 to 0.30 cm^2 after the infiltration of GDC nanoparticles.

关键词： Electrochemical carbon dioxide reduction reaction solid oxide electrolysis cell Double perovskite Infiltration

Cooperative effect of polyvinylpyrrolidone and HPMC E5 on dissolution and bioavailability of nimodipine solid dispersions and tablets

在线全文

学校读者我要写书评

暂无评论

Asian Journal of Pharmaceutical Sciences 2019年第6期14卷 668-676页

作者： Zhisu Sun Huicong Zhang Huiyang He Lingling Sun Xiaorui Zhang Qun Wang Kexin Li Zhonggui He Wuya College of Innovation Shenyang Pharmaceutical UniversityShenyang 110016China School of Pharmacy Shenyang Pharmaceutical UniversityShenyang 110016China Examination and Certification Center Liaoning InspectionShenyang 110036China

solid dispersion(SD)systems have been extensively used to increase the dissolution and bioavailability of poorly water-soluble drugs.To circumvent the limitations of polyvinylpyrrolidone(PVP)dispersions,HPMC E5 was applied in the formulation process and scaling-up techniques,simultaneously.In this study,SD of nimodipine(NMP)and corresponding tablets were prepared through solvent method and fluid bed granulating one step technique,respectively.Discriminatory dissolution media were used to obtain reliable dissolution results.Meanwhile,the stability study of SDs was investigated with storage under high temperature and humidity conditions.Moreover,the solubility of SDs was measured to explore the effect of carriers.The preparations were characterized by DSC,PXRD,and FTIR.Dramatical improvements in the dissolution rate of NMP were achieved by the ingenious combination of the two polymers.Binary NMP/PVP/HPMC-SDs released steadily,while the dissolution of single NMP/PVP-SDs decreased rapidly in water.The fluid-bed tablets(FB-T)possessed a similar dissolution behavior to the commercial Nimotop TM tablets.The characterization patterns implied that NMP existed in an amorphous state in our SDs.Furthermore,the results of stability tests suggested a better stability of the binary SDs.A special cooperative effect of PVP and HPMC was discovered on dissolution characteristics of NMP SDs and tablets,which could be extended to other drugs henceforth.Finally,the bioavailability of FB-T was evaluated in beagle dogs with Nimotop TM as the reference,and the results showed a higher AUC 0–12h value for FB-T.

关键词： solid dispersion Nimodipine HPMC E5 Fluid-bed Bioavailability

Overview of Al-based nanoenergetic ingredients for solid rocket propulsion

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2018年第5期14卷 357-365页

作者： Luigi T.DeLuca Politecnico di Milano MilanItaly Nanjing University of Science and Technology NanjingChina

The introduction of nano-sized energetic ingredients first occurred in Russia about 60 years ago and arose great expectations in the rocket propulsion community, thanks to the higher energy densities and faster energy release rates exhibited with respect to conventional ingredients. But, despite intense worldwide research programs, still today mostly laboratory level applications are reported and often for scientific purposes only. A number of practical reasons prevent the applications at industrial level: inert native coating of the energetic particles, nonuniform dispersion, aging, excessive viscosity of the slurry propellant, possible limitations in mechanical properties, more demanding safety issues, cost, and so on.This paper describes the main features in terms of performance of solid rocket propellants loaded with nanometals and intends to emphasize the unique properties or operating conditions made possible by the addition of the nano-sized energetic ingredients. Steady and unsteady combustion regimes are examined.

关键词： Nanoaluminum solid rocket propellant Burning rate Combustion Propulsion Performance

Crystallography of low Z material at ultrahigh pressure:Case study on solid hydrogen

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2020年第3期5卷 40-54页

作者： Cheng Ji Bing Li Wenjun Liu Jesse S.Smith Alexander Bjoorling Arnab Majumdar Wei Luo Rajeev Ahuja Jinfu Shu Junyue Wang Stanislav Sinogeikin Yue Meng Vitali B.Prakapenka Eran Greenberg Ruqing Xu Xianrong Huang Yang Ding Alexander Soldatov Wenge Yang Guoyin Shen Wendy L.Mao Ho-Kwang Mao Center for High Pressure Science and Technology Advanced Research Beijing 100094China High Pressure Collaborative AccessTeam Geophysical LaboratoryCarnegie Institution of WashingtonArgonneIllinois 60439USA Center for the Study of Matter at Extreme Conditions and Department of Mechanical and Materials Engineering Florida International UniversityMiamiFlorida 33199USA Advanced Photon Source Argonne National LaboratoryLemontIllinois 60439USA HPCAT X-Ray Science DivisionArgonne National LaboratoryLemontIllinois 60439USA MAX IV Laboratory Lund University22100 LundSweden Condensed Matter Theory Group Materials Theory DivisionDepartment of Physics and AstronomyUppsala UniversityUppsala S-75120Sweden Center for Advanced Radiation Sources University of ChicagoChicagoIllinois 60637USA Department of Engineering Sciences and Mathematics Lule°a University of Technology97187 Lule°aSweden Department of Geological Sciences Stanford UniversityStanfordCalifornia 94305USA Stanford Institute for Materials and Energy Sciences SLAC National Accelerator LaboratoryMenlo ParkCalifornia 94025USA

Diamond anvil cell techniques have been improved to allow access to the multimegabar ultrahigh-pressure region for exploring novel phenomena in condensedmatter.However,the onlyway to determine crystal structures of materials above 100 GPa,namely,X-ray diffraction(XRD),especially for lowZ materials,remains nontrivial in the ultrahigh-pressure region,even with the availability of brilliant synchrotron X-ray sources.In thiswork,we performa systematic study,choosing hydrogen(the lowest X-ray scatterer)as the subject,to understand how to better perform XRD measurements of low Z materials at multimegabar pressures.The techniques that we have developed have been proved to be effective in measuring the crystal structure of solid hydrogen up to 254GPa at room temperature[C.Ji et al.,Nature 573,558–562(2019)].Wepresent our discoveries and experienceswith regard to several aspects of thiswork,namely,diamond anvil selection,sample configuration for ultrahigh-pressure XRDstudies,XRDdiagnostics for low Z materials,and related issues in data interpretation and pressure calibration.Webelieve that these methods can be readily extended to other low Z materials and can pave the way for studying the crystal structure of hydrogen at higher pressures,eventually testing structural models of metallic hydrogen.

关键词： ultrahigh solid eventually

Synthesis and microstructure characterization of tetragonal Zr1–xTixO2 （x = 0–1） solid solutions

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2019年第9期35卷 1966-1976页

作者： Linggen Kong Inna Karatchevtseva Hanliang Zhu Meng Jun Qin Zaynab Aly Nuclear Fuel Cycle Research Australian Nuclear Science and Technology Organisation

Oxide powders of Zr1_xTixO2(x=0-1)solid solutions with micron-sized particles were synthesized via a solution combustion method.The synthesis process and Zr/Ti molar ratio were optimized to produce powders with the tetragonal crystal structure.X-ray diffraction,Raman spectroscopy and transmission electron spectroscopy results confirm that a full crystallization microstructure with the single tetragonal phase is obtained after calcination at 600℃while maintaining the crystallite size67 mol%exhibit a tetragonal crystal structure and the embedding Ti in ZrO2 improves the structure stability.The nitrogen sorption results indicate that the powders possess mesoporous morphology with medium specific surface areas(~10-50 m^2/g).Chemical stability tests show that these powders are relatively stable with negligible removal of titanium and zirconium after elution by 0.5 mol/L HC1.Density functional theory was used to calculate the most stable structure with low energy for the selected composition.

关键词： Tetragonal Titanium zirconate solid solution Chemical synthesis

Physical and mechanical properties of municipal solid waste incineration residues with cement and coal fly ash using X-ray Computed Tomography scanners

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2019年第3期13卷 640-652页

作者： Toshifumi MUKUNOKI Ta Thi HOAI Daisuke FUKUSHIMA Teppei KOMIYA Takayuki SHIMAOKA Faculty of Advanced Science and Technology Graduate School of Kumamoto UniversityKumamoto city 860-8555Japan Graduate school of Science and Technology Kumamoto UniversityKumamoto city 860-8555Japan Faculty of Geology VNU University of ScienceVietnam National University Hanoi334 Nguyen TraiHanoiVietnam Water and Material Cycles System Faculty of EngineeringKyushu UniversityFukuoka city 819-0395Japan

A significant volume of Municipal solid Waste incineration bottom ash and fly ash (i.e.,incineration residues) are commonly disposed as landfill.Meanwhile,reclamation of landfill sites to create a new land space after their closure becomes an important goal in the current fewer and fewer land availability scenario in many narrow countries.The objective of this study is to reclaim incineration residue materials in the landfill site by using cement and coal fly ash as stabilizers aiming at performing quality check as new developed materials before future construction.Indeed,physical and mechanical properties of these new materials should be initially examined at the micro scale,which is the primary fundamental for construction at larger scale.This research examines quantitative influences of using the combination of cement and coal fly ash at different ratio on the internal structure and ability of strength enhancement of incineration residues when suffering from loading.Couple of industrial and micro-focus X-ray computed tomography (CT) scanners combined with an image analysis technique were utilized to characterize and visualize the behavior and internal structure of the incineration residues-cement-coal fly ash mixture under the series of unconfined compression test and curing period effect.Nine types of cement solidified incineration residues in term of different curing period (i.e.,7,14,28 days) and coal fly ash addition content (i.e.,0%,9%,18%) were scanned before and after unconfined compression tests.It was shown that incineration residues solidified by cement and coal fly ash showed an increase in compression strength and deformation modulus with curing time and coal fly ash content.Three-dimension computed tomography images observation and analysis confirmed that solidified incineration residues including incineration bottom and fly ash as well as cement and coal fly ash have the deliquescent materials.Then,it was studied that stabilized parts play a more important role than spatial void distribution in i

关键词： mechanical property municipal solid waste incineration residues coal fly ash unconfined compression test image analysis X-Ray Computed Tomography scanners

Influences of the inner diameter of the solid shielding tube on the characteristics of the radio-frequency cold atmospheric plasma jet

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2019年第9期21卷 82-90页

作者： Muhammad Ajmal KHAN 李静李和平 Department of Engineering Physics Tsinghua University

Active control of the local environment of the cold atmospheric plasma(CAP) jet is of great importance in actual applications since the CAP operates in an open atmosphere with the inevitable entrainment of the surrounding cold air. In this paper, the solid shielding effects of the cylindrical quartz tubes with different inner diameters on the characteristics of the CAP jets driven by a radio-frequency(RF) power supply are studied experimentally. The experimental results show that the total length of the shielded plasma jet can be increased significantly by an appropriate combination of the quartz tube inner diameter and that of the plasma generator nozzle exit with other parameters being unchanged. This phenomenon may be qualitatively attributed to the loss of diffusion of the charged particles in the radial direction under different inner diameters of the quartz tubes. Compared with the plasma free jet, the plasma shielding jet is produced with optimized parameters including longer plasma jet length, higher concentrations of chemically reactive species, higher rotational, vibrational, and electron excitation temperatures when the inner diameters of the solid shielding tube and the generator nozzle exit are the same. A maximum plasma jet length of 52.0 cm is obtained in contrast to that of 5.0 cm of the plasma free jet in this study. The experimental results indicate that the solid shielding effect provides a new method for the active control of the local environment of the RF-CAP jet operating in an open atmosphere.

关键词： cold atmospheric plasma jet radio-frequency glow discharge solid shielding effect effect of the tube inner diameter active control of plasma jet characteristics

Thermodynamic data calculation for iron phases in sulfoaluminate cementitious materials prepared using solid wastes

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2019年第12期27卷 2989-2993页

作者： WenlongWang Guolin Li Lizhi Zhou Changzai Ren National Engineering Laboratory of Coal-fired Pollutants Emission Reduction Shandong Provincial Key Lab of Energy Carbon Reduction and Resource UtilizationShandong UniversityJinan 250061China

The preparation of sulfoaluminate cementitious materials(SCM)is a promising way to massively utilize solid wastes.Iron phases are significant in SCM system but the thermodynamic data of some key minerals,such as6 CaO·Al2 O3·2 Fe2 O3(C6 AF2)and 6 CaO·2 Al2 O3·Fe2 O3(C6 A2 F),are missing,which greatly hinders the SCM optimization in a theoretical way.This work,for the first time,calculated the standard formation enthalpy,Gibbs free energy of formation,entropy and molar heat capacity for C6 AF2 and C6 A2 F and lowered the errors to the least with the reference of C4 AF data in the literature.By building the function diagram of Gibbs free energy changes with temperature for the basic iron phase formation reactions with the obtained thermodynamic data,it is proved that the formation likeliness of C6 AF2 is higher than that of C6 A2 F,as is accordant to the literatures and verifies the correctness of obtained data.This work provides a good theoretical foundation to optimize SCM mineral system and to study relevant mechanism deeply.

关键词： Sulfoaluminate cement Iron phase Thermodynamic data Gibbs free energy solid waste utilization

Simulation analysis of municipal solid waste pyrolysis and gasification based on Aspen plus

在线全文

学校读者我要写书评

暂无评论

Frontiers in Energy 2019年第1期13卷 64-70页

作者： Na DENG Dongyan LI Qiang ZHANG Awen ZHANG Rongchang CAI Biting ZHANG School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China MOE Key Laboratory of Efficient Utilization of Low and Medium Grade Energy Tianjin 300350China Tianjin University Research Institute of Architectural Design&Urban Planning Tianjin 300072China

To predict and analyze the municipal solid waste(MSW)pyrolysis and gasification process in an updraft fixed bed more veritably and appropriately,numerical modeling based on Gibbs energy minimization was executed using the Aspen plus software.The RYield module was combined with the RGibbs module to describe the pyrolysis section,while the RGibbs module was used for the gasification section individually.The proposed model was used to forecast and analyze the target performance parameters including syngas composition,lower heating value(LHV)and carbon conversion rate under different conditions of the gasification temperatures,and ratios and types of gasifying agents.The results indicate that there is a good agreement between the experimental data and the simulated data obtained using this model.The predicted optimum gasification temperature is approximately 750°C,and the best ratio of water vapor as gasifying agent is around 0.4.The mixture of flue gas and water vapor has an economical and recycled prospect among four commonly used gasifying agents.

关键词： municipal solid waste(MSW) pyrolysis gasification Aspen plus simulation