检索结果-内蒙古大学图书馆

Rough-surfaced bimetallic copper–palladium alloy multicubes as highly bifunctional electrocatalysts for formic acid oxidation and oxygen reduction

引用

Green Energy & Environment 2019年第3期4卷 254-263页

作者： Dong Chen Linlin Xu Hui Liu Jun Yang State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center for Mesoscience Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences No.19A Yuquan RoadBeijing 100049China Zhongke Langfang Institute of Process Engineering Fenghua Road No 1Langfang Economic&Technical Development ZoneHebei 065001China

engineering the morphology of nanomaterials and modifying their electronic structure are effective ways to improve their performance in electrocatalysis. Through combining the co-reduction of Pd2+ and Cu2+ precursors with a digestive ripening process in oleylamine, we report the synthesis of copper-palladium(Cu-Pd) alloy multicubes with rough surfaces. Benefiting from their alloy and unique rough-surfaced structure,which provides ample edge/corner and step atoms as well as the electronic coupling between Cu and Pd leading to the lower of d-band center, the rough-surfaced Cu-Pd alloy multicubes show much better electrocatalytic performance not only for formic acid oxidation but also for oxygen reduction in comparison with those of spherical Cu-Pd alloy nanoparticles and commercial Pd/C catalyst. In contrast, we confirm that the rough-surfaced Cu-Pd alloy multicubes only exhibit very low Faradaic efficiency(34.3%) for electrocatalytic conversion of carbon dioxide(CO2) to carbon monoxide(CO) due to the presence of strong competing hydrogen evolution reaction, which results in their very poor selectivity for the reduction of CO2 to CO. The findings in this study not only offer a promising strategy to produce highly effective electrocatalysts for direct formic acid fuel cells, but also enlighten the ideas to design efficient electrocatalysts for CO2 reduction.

关键词： Copper–palladium Multicube Formic acid oxidation Oxygen reduction CO2 reduction

来源：评论

学校读者我要写书评

暂无评论

Simulation of ultrasonic attenuation in theelastic mixing particle system

引用

Chinese Journal of Acoustics 2018年第1期37卷 99-109页

作者： LI Yunsi SU Mingxu YANG Huinan FAN Fengxian CAI Xiaoshu Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering University of Shanghai for Science and Technology

For the study of predicting ultrasonic attenuation of elastic, spherical mixing par- ticles in the liquid-solid two-phase system, the Monte Carlo method （MCM） is introduced, serving as a probability and statistics technique to evaluate the inside ultrasonic events during the ultrasound propagation. On the basis of ultrasonic scattering and aborption, the continuous ultrasonic waves are represented as discrete and independent phonons. By recording the scat- tering events, tracing the trajectory of a moving phonon and calculating the number of phonons that finally reach the receiving transducer, the ultrasonic attenuation coefficient is obtained to be a frequence-dependent spectrum. Numerical investigations have been carried out to predict and compare the ultrasonic attenuation for a solid-liquid two-phase system with a single type particle. After verifing its feasibility, such a method is then appalied into mixing particle sys- tern, where the mixing iron particles and glass beads with various ratios are set as examples for the purpose of predicting ultrasonic attenuation for the monodisperse and polydisperse mixing particle systems. The results of MCM, the ECAH model, the Lloyd ~z Berry （LB） model and the Waterman model match well when the particle volume concentration is lower than 10%, corresponding to iron particles and glass beads respectively. In the case of two-phase system with mixing particles, it is shown that as the particle volume concentration increases to 10%, the variation of the ultrasonic attenuation coefficient with mixing ratio yields a nonlinear tendency. The physical properties of particles can also influence ultrasonic attenuation significantly.

关键词： Simulation of ultrasonic attenuation in theelastic mixing particle system

来源：评论

学校读者我要写书评

暂无评论

Influence of carbon coating on the electrochemical performance of SiO@C/graphite composite anode materials

引用

Chinese Physics B 2019年第6期28卷 438-445页

作者： Hao Lu Junyang Wang Bonan Liu Geng Chu Ge Zhou Fei Luo Jieyun Zheng Xiqian Yu Hong Li Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of Sciences(CAS)Beijing 100049China CAS Research Group on High Energy Density Lithium Batteries for EV Institute of ChemistryChinese Academy of SciencesBeijing 100190China Key Laboratory of Green Process Engineering State Key Laboratory of Multiphase Complex SystemsInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Tianmulake Excellent Anode Materials Co. Ltd.Changzhou 213300China

Silicon monoxide(SiO) has been considered as one of the most promising anode materials for next generation highenergy-density Li-ion batteries(LiBs) thanks to its high theoretical capacity. However, the poor intrinsic electronic conductivity and large volume change during lithium intercalation/de-intercalation restrict its practical applications. Fabrication of SiO/C composites is an effective way to overcome these problems. Herein, a series of micro-sized SiO@C/graphite(Si0@C/G) composite anode materials, with designed capacity of 600 mAh·g-1, are successfully prepared through a pitch pyrolysis reaction method. The electrochemical performance of SiO@C/G composite anodes with different carbon coating contents of 5 wt%, 10 wt%, 15 wt%, and 35 wt% is investigated. The results show that the SiO@C/G composite with15-wt% carbon coating content exhibits the best cycle performance, with a high capacity retention of 90.7% at 25℃ and90.1% at 45 0 C after 100 cycles in full cells with LiNi0.5Co0.2Mn0.3O2 as cathodes. The scanning electron microscope(SEM) and electrochemistry impedance spectroscopy(EIS) results suggest that a moderate carbon coating layer can promote the formation of stable SEI film, which is favorable for maintaining good interfacial conductivity and thus enhancing the cycling stability of SiO electrode.

关键词： lithium-ion battery silicon monoxide carbon coating anode material

来源：评论

学校读者我要写书评

暂无评论

Meshfree simulation of multiphase flows with SPH family methods

arXiv

引用

arXiv 2020年

作者： Chen, Feiguo State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China Innovation Academy for Green Manufacture Chinese Academy of Sciences Beijing100190 China

With meshfree and fully Lagrangian features of particle methods, smoothed particle hydrodynamics (SPH) is suitable to achieve high-accurate simulations of multiphase flows with large interfacial deformations, discontinuities, and multi- physics. In this review, the basic concept of SPH is first briefly introduced. Then, various implementations of SPH in regard to multiphase flow simulations are summarized and discussed. Some problems associated with SPH simulations of multiphase flows are suggested as requiring attention. Copyright © 2020, The Authors. All rights reserved.

关键词： Hydrodynamics

来源：评论

学校读者我要写书评

暂无评论

Experimental Study on Deliquification with Atomizing Nozzle in Gas Well

引用

IOP Conference Series: Earth and Environmental Science 2020年第1期555卷

作者： Yutang Gao Xiaobai Li Peng Chang Lei Liu State Key Laboratory of Multiphase Flow in Power Engineering Xi'an 710049 Shaanxi P.R. China

Gas is a clean energy resource in comparison with oil and coal. Liquid-loading problem is frequently encountered in the process of gas production. It would directly cause the production of gas wells decreasing, even off production. A number of deliquification techniques have been suggested for solving this kind of problem, but the available techniques are not yet widely applicable. Based on the analysis, the method of deliquification with atomizing nozzle in gas wells was put forward. The test bench was designed for studying the atomization of nozzles and the liquid entrainment of gas flow. The size distribution of atomized droplets was measured by Malvern laser grain size analyzer. The Sauter mean diameters of atomized droplets were analysed under different two-phase flow conditions. The results indicate that the designed nozzles have good atomization performances and show potential application for reducing liquid loading in gas wells.

关键词：

来源：评论

学校读者我要写书评

暂无评论

-growth orientation dependence of Ga2O3 nanowires on Cu3As seeds via vapor-solid-solid mechanism

引用

Journal of Alloys and Compounds 2021年 864卷 158786-158786页

作者： Wang, Hang Wang, Anqi Wang, Ying Yang, Zaixing Yang, Jun Han, Ning Chen, Yunfa School of Metallurgical Engineering Xi'an University of Architecture and Technology Xi'an710055 China State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing100190 China Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen361021 China Department of Physics School of Science Beijing Jiaotong University Beijing100044 China Center of Nanoelectronics and School of Microelectronics Shandong University Jinan250100 China

To accurately control semiconductor nanowires’ (NW) physical characteristics defining electronic, optical and sensor applications, it is necessary to understand their potential growth mechanism. In this study, the Ga2O3 NW growth orientation is found to be dependent on their Cu3As catalyst structure via vapor-solid-solid (VSS) mechanism. The Ga2O3 NWs are synthesized by vapor transport method at 700 °C below the Cu3As alloy eutectic temperature, which forms a solid structure on top of the NWs. The NWs have relatively uniform diameter of 40–60 nm and prefer to grow alongdirection. Energy-dispersive X-ray spectroscopy (EDS) and high-resolution transmission electron microscope (HRTEM) data provide strong evidence that the harvested Ga2O3 NWs are epitaxially grown from Cu3As-based (cubic and hexagonal) catalyst seeds. And Ga2O3{110} |Cubic Cu3As {210}, Ga2O3{110} |Cubic Cu3As {110} and Ga2O3 {110} | hexagonal Cu3As {110} have relatively low mismatch compared to other interface lattice planes, providing a key insight into the growth process according to the VSS mechanism. The thermodynamics driven composition changes in the growth process are elaborated in detail. © 2021 Elsevier B.V.

关键词： Nanowires

来源：评论

学校读者我要写书评

暂无评论

Photocatalytic water oxidation over BiVO_4 with interface energetics engineered by Co and Ni-metallated dicyanamides

引用

Chinese Journal of Catalysis 2018年第3期39卷 502-509页

作者： Yi Shang Fujun Niu Shaohua Shen International Research Centre for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710049 Shaanxi China

Photocatalytic water oxidation based on semiconductors usually suffers from poor charge transfer from the bulk to the interface,which is necessary for oxygen ***,we construct a hybrid artificial photosynthesis system for photocatalytic water *** system consists of BiVO4as the light harvester,a transitional metal complex(M(dca)2,M=Co,Ni,dca:dicyanamide)as the water oxidation catalyst,and S2O82?as a sacrificial electron *** system exhibits enhanced oxygen evolution activity when M(dca)2is *** BiVO4/Co(dca)2and Bi‐VO4/Ni(dca)2systems exhibit excellent oxygen evolution rates of508.1and297.7μmol/(h·g)compared to the pure BiVO4which shows a photocatalytic oxygen evolution rate of252.2μmol/(h·g)during6h of photocatalytic ***(dca)2is found to be more effective than Ni(dca)2as a water oxidation *** enhanced photocatalytic performance is ascribed to the M(dca)2‐engineered BiVO4/electrolyte interface energetics,and to the M(dca)2‐catalyzed surface water *** two factors lead to a decrease in the energy barrier for hole transfer from the bulk to the surface of BiVO4,which promotes the water oxidation kinetics.

关键词： Metal complex BiVO4 Water oxidation Photocatalysis Interfacial kinetics

来源：评论

学校读者我要写书评

暂无评论

Catalytic activity of flame-synthesized Pd/TiO2 for the methane oxidation following hydrogen pretreatments

引用

Particuology 2018年第6期16卷 58-64页

作者： Nafeng Wang Fang Niu Shuhao Wang Yun Huang State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy ofSdencesBeijing 100190China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China

A nanocatalyst composed of 10wt% Pd supported on TiO2 was synthesized using one-step flame spray pyrolysis with a highly-quenched premixed stagnation *** as-prepared nanoparticles,having a mean diameter of approximately 10nm,were then subjected to isothermal oxidation and reduction in a fixed bed *** potential roles of Pd and PdO as well as possible synergistic effects between these two active species were explored during methane *** lowest light-off temperature T20 was obtained at a Pd ratio of 53% and this result can be reasonably explained based on a surface Pd-PdO site pair ***,differences in the hysteresis behavior during methane oxidation were noted throughout a heating-cooling cycle over the temperature range of 200-600℃,such that the degree of hysteresis was strongly correlated with the Pd ratio.

关键词： Catalytic oxidation Palladium-based catalysts Flame-assisted spray pyrolysis Nanoparticles

来源：评论

学校读者我要写书评

暂无评论

GPU-based discrete element simulation on flow stability of flat-bottomed hopper

引用

Chinese Journal of Chemical engineering 2018年第1期26卷 43-52页

作者： Li Peng Zheng Zou Libo Zhang Qingshan Zhu Hongzhong Li State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChineseAcademy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

In this study, the flow stability of the flat-bottomed hopper was investigated via GPU-based discrete element method(DEM) simulation. With the material height inside the hopper reducing, the fluctuation of the flow rate indicates an unstable discharge. The flow regions of the unstable discharge were compared with that of the stable discharge, a key transformation zone, where the voidage showed the largest difference between unstable and stable discharge, was revealed. To identify the relevance of the key transformation zone and the hopper flow stability, the voidage variation of the key transformation zone with material height reducing was studied.A sharp increase in the voidage in the key transformation zone was considered to be the standard for judging the unstable hopper flow, and the ‘Top–Bottom effect' of the hopper was defined, which indicated the hopper flow was unstable when the hopper only had the top area and the bottom area, because the voidage of particles in the top area and the bottom area were both variables.

关键词： Stability Discrete element method（DEM） Granular flow Top-Bottom effect flow regions

来源：评论

学校读者我要写书评

暂无评论

Synthesis of AgI/Bi2MoO6 nano-heterostructure with enhanced visible-light photocatalytic property

引用

Progress in Natural Science:Materials International 2018年第2期28卷 235-241页

作者： Li Zhang Hongcheng Teng Jiancheng Zhou Yueming Sun Naixu Li Maochang Liu Dengwei Jing School of Chemistry and Chemical Engineering Southeast University Department of Chemical and Pharmaceutical Engineering Southeast University Chengxian College Jiangsu Province Hi-Tech Key Laboratory for Bio-medical Research Southeast University International Research Center for Renewable Energy & State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Suzhou Academy of Xi'an Jiaotong University

A novel nano-heterostructure of Ag I/Bi2MoO6photocatalyst was successfully synthesized via a facile depositionprecipitation method. The samples were systematically characterized by X-ray diffraction, scanning and transmission electron microscopy, X-ray photoemission spectroscopy, UV–Vis absorption spectroscopy, and photoluminescence spectra. While sole Bi2MoO6or Ag I showed poor activity toward photocatalytic rhodamine B degradation, the nano-heterostructure was found with superior performance. The AgI/Bi2MoO6composite with an optimal content of 20 wt% Ag I exhibited the highest photocatalytic degradation rate. Rhodamine B was totally degraded within 75 min visible-light irradiation. Moreover, the hybrid photocatalyst also showed a fairly good stability for several-cycle reuse. This study indicates that the AgI/Bi2MoO6nano-heterostructure can be used as an effective candidate for photocatalytic degradation of organic pollutants.

关键词： Heterostructure Photocatalyst RhB-degradation

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：