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Glucose-derived carbon sphere supported cop as efficient and stable electrocatalysts for hydrogen evolution reaction

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Journal of Energy Chemistry 2017年第6期26卷 1147-1152页

作者： Bangde Luo Ting Huang Ye Zhu Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education Hubei Key Laboratory of Material Chemistry and Service Failure School of Chemistry and Chemical Engineering Huazhong University of Science and Technology Department of Applied Physics The Hong Kong Polytechnic University

Glucose-derived carbon sphere supported cobalt phosphide nanoparticles（Co P/C） were synthesized via a concise two-step method. The electrochemical measurement results indicate that the Co P/C prepared at 900 ℃ presents excellent electrocatalytic performance for hydrogen evolution reaction（HER）. The overpotential at a current density of 10 m A cmis 108 and 163 mV in 0.5 M HSOand 1 M KOH, respectively, and maintains its electrocatalytic durability for at least 10 h. This work supplies a new field to challenge the construction of electrocatalysts for HER through using cost-effective carbon supported transition metal phosphides.

关键词： cop Hydrogen evolution reaction Non-noble electrocatalysts Carbon sphere

集成引射器与机械过冷的CO_(2)冷热联供系统性能分析

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制冷学报 2023年第6期44卷 69-76,109页

作者：代宝民赵瑞瑞刘圣春钱家宝徐田雅慧刘晨杨佩芳天津商业大学天津市制冷技术重点实验室天津300134

为提高CO_(2)系统用于建筑全年空间供热供冷的性能,本文提出集成引射器与机械过冷的跨临界CO_(2)冷热联供系统(EJ-DMS)。通过构建系统的热力学模型,以性能系数(cop)为目标函数,采用遗传算法对排气压力和过冷度进行优化,并对系统应用于5... 详细信息

为提高CO_(2)系统用于建筑全年空间供热供冷的性能,本文提出集成引射器与机械过冷的跨临界CO_(2)冷热联供系统(EJ-DMS)。通过构建系统的热力学模型,以性能系数(cop)为目标函数,采用遗传算法对排气压力和过冷度进行优化,并对系统应用于5个典型城市的能耗、全年性能系数(cop_(ann))进行场景分析。结果表明:EJ-DMS相比常规机械过冷系统、常规引射系统,cop在制热和制冷模式下分别提高10.90%、5.58%和8.99%、18.12%,cop_(ann)分别提高7.95%和5.98%。EJ-DMS相比常规引射系统在制热和制冷模式下排气压力分别降低0.47 MPa和0.77 MPa。此外,EJ-DMS系统在广州和哈尔滨运行时的cop_(ann)提升率最大,表明其更适合环境温度较高或较低的地区,如夏热冬暖和严寒地区。本文可为CO_(2)冷热联供系统的构建和优化提供理论参考。

关键词：自然工质CO_(2) 冷热联供引射器机械过冷 cop

Exploring heating performance of gas engine heat pump with heat recovery

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Journal of Central South University 2016年第8期23卷 1931-1936页

作者：董付江刘凤国李先庭尤学一赵冬芳 School of Energy and Safety Engineering Tianjin Chengjian University School of Architecture Tsinghua University School of Environmental Science and Engineering Tianjin University

In order to evaluate the heating performance of gas engine heat pump(GEHP) for air-conditioning and hot water supply, a test facility was developed and experiments were performed over a wide range of engine speed(1400-2600 r/min), ambient air temperature(2.4-17.8 °C) and condenser water inlet temperature(30-50 °C). The results show that as engine speed increases from 1400 r/min to 2600 r/min, the total heating capacity and energy consumption increase by about 30% and 89%, respectively; while the heat pump coefficient of performance(cop) and system primary energy ratio(PER) decrease by 44% and 31%, respectively. With the increase of ambient air temperature from 2.4 °C to 17.8 °C, the heat pump cop and system PER increase by 32% and 19%, respectively. Moreover, the heat pump cop and system PER decrease by 27% and 15%, respectively, when the condenser water inlet temperature changes from 30 °C to 50 °C. So, it is obvious that the effect of engine speed on the performance is more significant than the effects of ambient air temperature and condenser water inlet temperature.

关键词：燃气机热泵制热性能冷凝器进水温度热回收发动机转速空气温度 cop 热水供应

cop/g-CN复合材料的制备及其光催化还原CO性能

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化工环保 2023年

作者：郑国宏张春雷陈旻澍蔡炜新疆维吾尔自治区气象技术装备保障中心新疆维吾尔自治区气象服务中心南京信息工程大学环境科学与工程学院

采用水热法制备了cop/g-C3N4复合材料，将其用于光催化还原CO2，结合XRD、SEM-EDS、TEM、XPS、UV-Vis DRS、PL、电化学测试和原位DRIFTS技术建立了复合光催化剂的构效关系，并探究了其光催化还原CO2的机理。实验结果表明，相比于纯g-C3N... 详细信息

采用水热法制备了cop/g-C3N4复合材料，将其用于光催化还原CO2，结合XRD、SEM-EDS、TEM、XPS、UV-Vis DRS、PL、电化学测试和原位DRIFTS技术建立了复合光催化剂的构效关系，并探究了其光催化还原CO2的机理。实验结果表明，相比于纯g-C3N4，cop的引入使甲烷的产率提升了近2倍，同时产生了新的还原产物甲醇，甲烷和甲醇的产率分别为104.23 μmol/(g·h)和63.83 μmol/(g·h)。表征结果显示，偏向金属特性的cop颗粒均匀分布在g-C3N4片状结构上，二者通过电子相互作用形成紧密接触的异质结结构，一方面可显著抑制光生载流子的复合，另一方面可有效建立内建电场，加速光生载流子从体相到催化剂表面的迁移，从而提升催化剂的光催化还原CO2性能。

关键词： CO 还原光催化 cop g-C N 构效关系

On the Use of Nanofluids in Solar Energy Applications

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Journal of Thermal Science 2020年第3期29卷 513-534页

作者： CUCE Erdem CUCE Pinar Mert GUCLU Tamer BESIR Ahmet Burhaneddin Department of Mechanical Engineering Faculty of EngineeringRecep Tayyip Erdogan UniversityZihni Derin Campus53100 RizeTurkey Low/Zero Carbon Energy Technologies Laboratory Faculty of EngineeringRecep Tayyip Erdogan UniversityZihni Derin Campus53100 RizeTurkey Department of Energy Systems Engineering Faculty of EngineeringRecep Tayyip Erdogan UniversityZihni Derin Campus53100 RizeTurkey

Renewable energy technologies are in the centre of interest to narrow the gap between fossil fuels and clean energy systems.The dominant role of solar energy systems among the alternatives is beyond question owing to being associated with an infinite energy source,well-documented theory,simplicity,eco-friendly structure and notably higher energy and exergy efficiency range compared to other renewables.However,in solar energy systems,conventional working fluids with poor thermophysical properties are still utilised.In other words,further improvements are still available in the said systems by the use of unique nanoparticles with superior thermal,electrical,optical and mechanical properties.Within the scope of this research,the applications of nanofluids in various solar energy systems such as tracking and non-tracking solar collectors,photovoltaic/thermal systems,solar thermoelectric devices,solar stills,solar thermal energy storage systems,solar greenhouses and solar ponds are comprehensively analysed.Relevant comparisons and discussions are proposed for the potential impacts of various nanofluids on coefficient of performance(cop)and thermodynamic performance figures of solar energy systems such as energy and exergy efficiency,effectiveness and productivity.Some challenges of nanofluids are also addressed which need to be resolved in further works.

关键词： nanofluids solar energy applications thermal and electrical performance cop cost

Performance Analysis of Thermoacoustic Refrigerator of 10 W Cooling Power Made up of Poly-Vinyl-Chloride for Different Parallel Plate Stacks by Using Helium as a Working Fluid

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Journal of Thermal Science 2021年第6期30卷 2037-2055页

作者： N V Shivakumara BHEEMSHA Arya Department of Mechanical Engineering BMS College of EngineeringBengaluru 560019India Department of Mechanical Engineering Government PolytechnicChannasandraBengaluru 560067India

Refrigerants are usually provided in the conventional refrigeration system although the refrigerants produce Chlorofluorocarbons(CFCs)and Hydro-chlorofluorocarbons(HCFCs),which are hazardous to the environment.However,these disadvantages can be overcome by using air or inert gas in the thermoacoustic refrigeration system.In the present experimental work,helium is used as a working gas with an operating pressure range of 0.2 MPa to 1.0 MPa in order to study the performance of thermoacoustic refrigerator(TAR)which is fabricated using Poly-Vinyl-Chloride(PVC).The parallel plate stacks with different porosity ratios have been considered to study the performance of TAR.The temperature difference between the hot and cold heat exchanger and acoustic dynamic pressure were recorded by using Bruel and Kjaer data acquisition system under different operating conditions.The effect of different operating parameters such as operating frequency(200 Hz to 600 Hz),cooling load(2 W to 10 W)and drive ratio(0.6%to 1.6%)have also been considered to study the performance of TAR.The TAR also modeled in DeltaEC software and the results are compared with the experimental outcomes and found to be in good agreement.The experimental results show that-2.1℃is the lowest temperature measured at cold heat exchanger by achieving the highest temperature difference of about 32.9℃.An improvement is around 36%as compared to that of previous experiments that used aluminium TAR.The highest Coefficient of Performance(cop)and the Relative Coefficient of Performance(copR)are found to be 2.024 and 0.217,respectively.

关键词： thermoacoustic refrigerator parallel plate stack porosity ratio temperature difference cop copR

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离心式冷水机组性能仿真研究

制冷学报 2023年第3期44卷 74-80页

作者：罗毅章立标杭炳炳龚程程浙江国祥股份有限公司上虞312300

针对离心式冷水机组的性能特点,本文提出在通过最大电流判断的最大能力和通过喘振判断的最小能力范围内,采用压缩机功率和冷凝器传热计算迭代出较为精确的机组性能仿真算法。在此基础上,开发了集壳管式换热器传热计算,离心压缩机性能、... 详细信息

针对离心式冷水机组的性能特点,本文提出在通过最大电流判断的最大能力和通过喘振判断的最小能力范围内,采用压缩机功率和冷凝器传热计算迭代出较为精确的机组性能仿真算法。在此基础上,开发了集壳管式换热器传热计算,离心压缩机性能、喘振预测等模型为一体的离心式冷水机组性能仿真软件,并通过样机测试验证了软件的仿真精度。结果表明:全负荷范围内cop、冷冻水压降、冷却水压降、功率、蒸发温度、冷凝温度的最大误差分别为6.43%、7.28%、4.45%、6.87%、3.83%、1.24%,实现了离心式冷水机组在不同负荷下的冷冻水温度、冷却水温度、流量等多元参数的性能仿真计算。

关键词：离心式冷水机组软件研发仿真计算 cop

送风温度对车用跨临界CO_(2)制冷系统影响的仿真研究

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制冷学报 2022年第4期43卷 96-102页

作者：乔义友方健珉殷翔孙西峰曹锋西安交通大学能源与动力工程学院西安710049 东风汽车有限公司技术中心武汉430056

为研究送风温度对实际车用跨临界CO_(2)制冷系统综合性能的影响,借助GT-Suite仿真软件,建立了单级跨临界CO_(2)制冷系统的仿真模型。基于设计的三种工况,在风量设置上限的情况下对比了不同送风温度下系统的性能,提出了有效cop_(eff)的... 详细信息

为研究送风温度对实际车用跨临界CO_(2)制冷系统综合性能的影响,借助GT-Suite仿真软件,建立了单级跨临界CO_(2)制冷系统的仿真模型。基于设计的三种工况,在风量设置上限的情况下对比了不同送风温度下系统的性能,提出了有效cop_(eff)的概念并对此进行研究。结果表明:在其他工况相同的条件下,提高送风温度可以提高系统的cop、有效cop_(eff)以及带风机功耗的有效cop_(eff,b);在低冷负荷工况下,考虑系统风机功耗后的综合性能cop_(b)存在最优值为3.819,即系统存在对应的最优送风温度,但当负荷增大至一定水平时,最优送风温度不再存在。

关键词：跨临界CO_(2)制冷系统送风温度 cop 系统性能

不同进口结构对热泵热水器释能过程性能实验研究

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制冷学报 2022年第3期43卷 115-120,141页

作者：秦露雯杜明浩沈立第李舒宏东南大学能源与环境学院南京210096

为提高空气源热泵热水器释能过程热水输出率与能效比,本文设计了一种弧形挡板型进口结构,搭建了热泵热水器实验台,以热水输出率和系统cop为评价指标,对比实验了含新型挡板进口结构的热泵热水器与直接型和侧进型进口结构热泵热水器的性能... 详细信息

为提高空气源热泵热水器释能过程热水输出率与能效比,本文设计了一种弧形挡板型进口结构,搭建了热泵热水器实验台,以热水输出率和系统cop为评价指标,对比实验了含新型挡板进口结构的热泵热水器与直接型和侧进型进口结构热泵热水器的性能,获得弧形挡板进口对热泵热水器释能过程运行性能的影响特性。结果表明:弧形挡板型进口结构能显著改善水箱沿高度方向的热分层现象;当进口流量在5~10 L/min之间变化时,弧形挡板型进口结构比直接型进口结构热水输出率提升52.87%~96.60%,系统cop提升7.14%~7.40%;比侧进型进口结构热水输出率提升38.37%~76.99%,系统cop提升3.22%~5.53%。随着进口流量的增加,性能提升越显著。弧形挡板型进口结构在给定的三种进口流量下始终优于另外两种进口结构,可实现热水输出率和系统cop双高效的运行效果。

关键词：进口结构弧形挡板热水输出率 cop 双高效