检索结果-内蒙古大学图书馆

Core-shell Ag-Pt nanoparticles:A versatile platform for the synthesis of heterogeneous nanostructures towards catalyzing electrochemical reactions

引用

Chinese Chemical Letters 2021年第11期32卷 3288-3297页

作者： Danye Liu Niuwa Yang Qing Zeng Hui Liu Dong Chen Penglei Cui Lin Xu Chaoquan Hu Jun Yang State Key Laboratory of Multiphase Complex Systems and Center of Mesoscience Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Nanjing IPE Institute of Green Manufacturing Industiy Nanjing 211100China School of Chemistry and Materials Science Jiangsu Key Laboratoiy of New Power BatteriesNanjing Normal UniversityNanjing 210023China

Heterogeneous nanostructures that are defined as a hybrid structure consisting of two or more nanoscale domains with distinct chemical compositions or physical characteristics have attracted intense efforts in recent *** this review,we focus on the introduction of a number of heterogeneous nanostructures derived using core-shell Ag-Pt nanoparticles as starting materials,including hollow,dimeric and composite structures and also highlight their application in catalyzing electrochemical reactions,e.g.,methanol oxidation reaction and oxygen reduction *** review not only shows the capability of core-shell Ag-Pt nanoparticles in producing various heterogeneous nanostructures as starting templates,but also highlights the structural design or electronic interaction that endows the heterogeneous nanostructures with enhanced catalytic properties either in methanol oxidation or in oxygen ***,we also make some perspectives for more heterogeneous nanostructures that may be prepared by using core-shell Ag-Pt particles or their derivatives so as to offer the readers the opportunities and challenges in this field.

关键词： Heterogeneous nanostructures Core-shell Electrochemical reaction Methanol oxidation reaction Oxygen reduction reaction

来源：评论

学校读者我要写书评

暂无评论

Energy consumption characteristics and energy saving potential of thermal power plants under ultra-low power load ratio conditions

引用

Energy 2025年 330卷

作者： Zeyu Du Ming Liu Yang Wang Yu Zhou Yongliang Zhao Junjie Yan Xi'an Jiaotong University State Key Laboratory of Multiphase Flow in Power Engineering Xi’an 710049 China China Huaneng Group Co LTD Beijing 100032 China

The operational flexibility of thermal power plants should be enhanced to accommodate the high penetration of photovoltaic and wind power within the power grid. The energy efficiency deteriorates heavily when thermal power plants operate under ultra-low power load ratio conditions, which will increase the carbon emissions of the low-carbon power system. To achieve the energy saving under ultra-low power load ratio condition, the CFPP's (coal-fired power plant) off-design condition models were developed, and the thermal system regulation with additional losses of the CFPP operates under below 30 % power load ratio condition was simulated. Then, influences of the degradation factors on the energy consumption characteristics under ultra-low power load ratio condition were evaluated. Moreover, the carbon emission rate of power generation considering the renewable power accommodation was evaluated. Results show the degradations of turbines' internal efficiencies are the main source of internal losses, and the degradation of boiler's efficiency and the increase of the auxiliary power ratio are the main source of external losses. The total carbon emission rate of power generation decreases by 21.98 g/(kW h) with the power load ratio of CFPP decreasing from 30 % to 20 % due to the increased accommodation of renewable power. Finally, energy saving potential evaluations under ultra-low power load ratio conditions were conducted. The net coal consumption rate is 298.56 g/(kW h) and 522.39 g/(kW h) when the thermal power plant operates under 100 % and 20 % power load ratio conditions respectively. The maximal energy saving potential of b net under ultra-low power load condition are 87.25, 29.47, 25.05, 2.33 and 1.05 g/(kW h), for the degradation of isentropic efficiency of turbine, the degradation of boiler's efficiency, the increase of auxiliary power ratio, the additional drainage water of the boiler and the switching action of BFPT's supply steam, respectively.

关键词： Fossil fuel power plants

来源：评论

学校读者我要写书评

暂无评论

Numerical study of collision behavior of melt drops during fuelcoolant interaction

Numerical study of collision behavior of melt drops during f...

引用

2020 International Conference on Nuclear engineering, ICONE 2020, collocated with the ASME 2020 power Conference

作者： Wen, Panpan Li, Gen Gao, Jinchen Li, Yupeng Yamaji, Akifumi Yan, Junjie State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China Cooperative Major in Nuclear Energy Waseda University Tokyo169-8555 Japan

ISBN: (纸本)9780791883785

The collision dynamics between two droplets plays an important role in various disciplines of nature and practical interests, such as fuel-coolant interaction (FCI), fuel combustion in engines, and various spraying process. FCI presents in nuclear reactor severe accident when the melt relocates into the coolant in the lower head with violent disturbance and vigorous heat transfer. The purpose of this study is to investigate the collision behavior of melt droplets during fuel-coolant interaction. The collision of two equal-sized droplets has been simulated in 3D by using the volume of fluid (VOF) and adaptive mesh refinement method. The numerical simulations of tetradecane droplet collision were carried out to validate the numerical methods. The results showed good agreement with the experiments. Furthermore, the simulations of uranium dioxide (UO2) droplets collision in coolant were carried out. The results showed that the contact area between droplets and coolant increased with time first and then decreased. With the increase of Weber number, the contact area of maximum in the droplet collision increased. Break happened in the later period and many child droplets formed. The number of child droplets increased with the increase of Weber number. In addition, the size distribution of little droplets was investigated. © 2020 American Society of Mechanical Engineers (ASME). All rights reserved.

关键词： Coolants

来源：评论

学校读者我要写书评

暂无评论

Suppressing Condensation Frosting Using Micropatterned Ice Walls

SSRN

引用

SSRN 2022年

作者： Zuo, Zichao Zhao, Yugang Li, Kang Zhang, Hua Yang, Chun Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering School of Energy and Power Engineering University of Shanghai for Science and Technology Shanghai200093 China Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development Center Sichuan Mianyang621000 China School of Mechanical and Aerospace Engineering Nanyang Technological University Singapore639798 Singapore

Condensation frosting is encountered ubiquitously in our daily life and numerous industrial applications, rooting many detrimental consequences in heat transfer and mechanical stabilities. In latest decades, both active de-frosting and passive anti-frosting methods have been developed. In this work, we adopt the concept of three-dimensional overlapping dry zones by patterning microscopic ice walls on a smooth substrate, engendering a sustainable frost coverage of less than 10%. Patterned ice walls prevent vapor deposition on the substrate base by absorbing all incoming moisture on upper sidewalls, leaving the substrate base free of contaminates from both frost and condensate. To ensure vapor preferentially depositing on upper sidewalls, a critical ice wall height exists, below which fine ice grains initiate in the adjacent of the substrate base and grow substantially faster, compromising the anti-frosting performance. The proposed surface shows reasonable durability when exposed to varying substrate supercooling, and frost coverage may increase due to covering and fracturing of the out-of-plane growth of feather-like ice clusters at large substrate supercooling. Our findings provide an effective anti-frosting surface design that doesn’t require any chemical or mechanical modifications on the targeted surfaces, showing great advantages compared to conventional icephobic surface designs. © 2022, The Authors. All rights reserved.

关键词： Ice

来源：评论

学校读者我要写书评

暂无评论

Strong Photo-Thermal Coupling Effect Boosts Co2 Reduction into Ch4 in a Concentrated Solar Reactor

SSRN

引用

SSRN 2023年

作者： Li, Naixu Xu, Lei Ren, Yuqi Liu, Maochang Zhu, Fengfan Cheng, Miao Zhou, Jiancheng Chen, Wenshuai Wang, Ke Wang, Nan School of Chemistry and Chemical Engineering Southeast University No.2 Dongnandaxue Road Jiangsu Nanjing211189 China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University No.28 Xianning West Road Shaanxi Xi'An710049 China Key Laboratory of Bio-Based Material Science and Technology Ministry of Education Northeast Forestry University No. 26 Hexing Road Harbin150040 China

This study is dedicated to solving the problems of low energy utilization and low yield in the conventional photocatalytic CO2 reduction process. In this work, a novel concentrated solar (light) reactor was established to improve solar energy utilization efficiency and CO2 conversion rate by concentrating light and heat (that is, by converting light into heat). The TF@TNT/0.4CoOx-0.1CuO monolithic photocatalyst based on titanium foam was designed and prepared. The results showed that the light intensity increased by ~10.6 times (from 400 mW/cm2 to 4266 mW/cm2) while the yield of CH4, the product of CO2 reduction driven by photo-thermal coupling effect, increased by ~220 times (from 0.53 µmol/cm2 to 116.4 µmol/cm2) in the concentrated solar (light) reactor. The results of CH4 yield, electrochemical measurement, and apparent activation energy calculation were investigated in the concentrator reactor under the conditions of concentrated and non-concentrated irradiation of simulated sunlight in different wavelength ranges. It can be found that the concentrated light and the induced photo-thermal coupling effect can significantly reduce the reaction barrier (from 41.62 to 31.51 kJ/mol) and improve the conversion efficiency of solar energy to chemical energy by ~15 times. This provides a potentially feasible method for efficient and green utilization of CO2 driven by solar energy. © 2023, The Authors. All rights reserved.

关键词： Solar energy

来源：评论

学校读者我要写书评

暂无评论

Experimental study on safe operation state of W-shaped flame boiler 7

Experimental study on safe operation state of W-shaped flame...

引用

7th International Conference on power engineering, ICOPE 2019

作者： Wen, Du Yao, Yashu Li, Lian Zhou, Qulan Li, Na Deguchi, Yoshihiro State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China Graduate School of Advanced Technology and Science Tokushima University Tokushima770-8501 Japan

To get more acknowledges about W-shaped flame boiler, scaled down experiment system was set up to collect the basic data about temperature, strain, stress, shear and heat flux distribution of W-shaped flame boiler. The results showed that temperature distribution is mainly decided by the distance of the flame. Area which is washed against by flame shows high temperature. The temperature on the front wall is higher than rear wall, especially on the connection zone between furnace chamber and upper ash hopper. Heat flux distribution is dominated by both radiation and convective heat transfer. High heat flux zone is surrounding the burners and it is decided by temperature in furnace chamber. Medium heat flux zone is along the route of the gas fume and it is decided by gas fume's convective heat transfer. Strain distribution is well matched with temperature distribution especially in high strain zone. And the magnitude of stress depends on temperature gap, but the direction depends on both temperature gap and external constraints. In this experiment, we find that front wall is more vulnerable than other walls especially on the connection zone between furnace chamber and upper ash hopper. It is of high value on boiler safety operating and on optimization of the furnace chamber's structure. © ICOPE 2019 - 7th International Conference on power engineering, Proceedings. All rights reserved.

关键词： Temperature distribution

来源：评论

学校读者我要写书评

暂无评论

A novel coal-fired chp system integrated with steam ejectors to realize heat-power decoupling and energy saving

A novel coal-fired chp system integrated with steam ejectors...

引用

2019 Canadian Society for Civil engineering Annual Conference, CSCE 2019

作者： Liu, Miaomiao Liu, Ming Zhao, Shuran Song, Gege Yan, Junjie State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an710049 China Key Laboratory of Heat Transfer enhancement and Process Energy Conservation Technology Ministry of education Beijing University Beijing100025 China

ISBN: (纸本)9780791883747

Traditional combined heat and power (CHP) units should run in the heat-controlled mode. The adjustable range of power load is restricted by the heat load, and the minimum power load increases with the heat load. Because of high penetration of intermittent renewable power, operational flexibility of CHP units is highly required. It is necessary to adopt some technical solutions to realize heat-power decoupling for CHP units. To find a heat-power decoupling method with low investment and high energy efficiency, the steam ejectors, simple in structure and low in cost, are applied to design a novel heat-power decoupling system in this study. Steam ejectors can recover the waste heat of exhaust steam of steam turbines. Therefore, the integration of steam ejector may realize heat-power decoupling and energy saving simultaneously. Three heat-power decoupling systems with steam ejectors are designed. The heat-power decoupling performance and energy consumption characteristics of these systems are investigated with a reference 330 MW coal-fired CHP unit. Results show that all three modified systems can realize heat-power decoupling. The heat-power decoupling performance of improved system III is the best, and improved system I has the least coal consumption rate for power generation. Copyright © 2020 ASME.

关键词： Thermal load

来源：评论

学校读者我要写书评

暂无评论

Novel Design of In-Situ Hydrogen Sorption/Storage Integrated Enhanced Hydrogen Production in Supercritical Co2 Gasification, Air Gasification, and Steam Gasification from Biomass

SSRN

引用

SSRN 2023年

作者： Yang, Tiebing Tie Dou, Binlin Zhang, Hua Wu, Kai Ning, Luo Chen, Haisheng Xu, Yujie Li, Wei Wu, Chunfei School of Energy and Power Engineering Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering University of Shanghai for Science and Technology Shanghai200093 China Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing100190 China Department of Energy Engineering Zhejiang University Hangzhou310027 China School of Chemistry and Chemical Engineering Queen's University Belfast BelfastBT7 1NN United Kingdom

Novel process on in-situ hydrogen sorption/storage during water gas shift (WGS) was proposed and the enhanced hydrogen production in supercritical CO2 gasification (CG), air gasification (AG), and steam gasification (SG) from biomass was integrated. The effects of temperature, pressure, steam-to-carbon (S/C) ratio, and adsorbent content for in-situ hydrogen sorption/storage on the enhanced hydrogen production were determined. The energy and exergy analysises under different thermodynamic conditions were calculated and compared. The results show that as the temperature increases, the hydrogen conversion and yield from water gas shift (WGS) reaction with in-situ hydrogen sorption/storage based on Mg-based sorbent were greatly increased, in which SG has the highest hydrogen yield and AG has the highest hydrogen conversion. The steam-to-carbon (S/C) ratio has a positive effect on the hydrogen production for all the processes, and also presents an effect on in-situ hydrogen sorption/storage during WGS. The methanation reaction was greatly inhibited by AG. The energy requirement order was SG> CG >AG, and the system energy can be supplied by in-situ hydrogen sorption/storage. © 2023, The Authors. All rights reserved.

关键词： Biomass

来源：评论

学校读者我要写书评

暂无评论

聚丙烯酸酯修饰铜电极用于电化学二氧化碳还原选择性生成多碳产物（英文）

引用

Science Bulletin 2024年第15期 2395-2404页

作者：石玉川张凯妮董崇礼 Ta Thi Thuy Nga 汪淼魏代星王佳琳王亦清沈少华 International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Department of Physics Tamkang University

Highly selective production of value-added multicarbon(C2+) products via electrochemical CO2reduction reaction（eCO2RR） on polycrystalline copper（Cu） remains ***,the facile surface modification using poly（α-ethyl cyanoacrylate）(PECA) is presented to greatly enhance the C2+selectivity for eCO2RR over polycrystalline Cu,with Faradaic efficiency（FE） towards C2+products increased from30.1% for the Cu electrode to 72.6% for the obtained Cu-PECA electrode at -1.1 V *** hydrogen electrode（RHE）.Given the well-determined FEs towards C2+products,the partial current densities for C2+production could be estimated to be-145.4 mA cm-2for the Cu-PECA electrode at -0.9 V *** in a homemade flow ***-situ spectral characterizations and theoretical calculations reveal that PECA featured with electron-accepting-C≡N and-COOR groups decorated onto the Cu electrode could inhibit the adsorption of *H intermediates and stabilize the *CO intermediates,given the redistributed interfacial electron density and the raised energy level of d-band center（Ed） of Cu active sites,thus facilitating the C-C coupling and then the C2+selective *** study is believed to be guidable to the modification of electrocatalysts and electrodes with polymers to steer the surface adsorption behaviors of reaction intermediates to realize practical eCO2RR towards value-added C2+products with high activity and selectivity.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Thermal Stress in a Circular Nano-Inhomogeneity

SSRN

引用

SSRN 2022年

作者： Huang, Haojie Xing, Shichao Song, Kun School of Energy and Power Engineering University of Shanghai for Science and Technology Shanghai China School of Energy and Power Engineering Shanghai Key Laboratory of Power Enegy in Multiphase Flow and Heat Transfer Shanghai China Key Laboratory of Construction Hydraulic Robots of Anhui Higher Education Institutes Tongling University Tongling244061 China School of Mechanical and Power Engineering Nanjing Tech University 30 Puzhu South Road Jiangsu Nanjing China

The thermal stress of nanocomposites is worth studying in that the extreme stress affects its reliability. In this paper, we propose a set of interfacial conditions to simulate the interfacial phonon scattering and interfacial elasticity in the nanocomposite, and obtain closed-form solutions for the thermal-elastic fields around the circular nano-inhomogeneity. The results show that the interfacial thermal stress within matrix is more sensitive to interfacial phonon scattering than that in the nano-inhomogeneity, while the size change of inhomogeneity has greater impact on the stress of the nano-inhomogeneity than that of the matrix. In view of the significant effects of thermal conductivities and thermal expansion coefficients on the thermal stress around inhomogeneity, the maximum von Mises stress is reduced up to three orders of magnitude by adjusting these parameters. More importantly, the thermal stresses within matrix and inhomogeneity can be respectively designed as "zero" even though the nanocomposite is subjected to a large thermal loading, which is viewed as an update mechanism of "neutral inhomogeneity". Our work provides guidance for the design of nanocomposites and has important potential applications. © 2022, The Authors. All rights reserved.

关键词： Thermal stress

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：