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Hydrogen generation from methanol reforming for fuel cell applications: A review

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Journal of Central South University 2020年第4期27卷 1074-1103页

作者： sun Zhao sun zhi-qiang School of Energy Science and Engineering Central South UniversityChangsha 410083China

Methanol is regarded as an important liquid fuel for hydrogen storage, transportation, and in-situ generation due to its convenient conveyance, high energy density, and low conversion temperature. In this work, an overview of state-of-the-art investigations on methanol reforming is critically summarized, including the detailed introduction of methanol conversion pathways from the perspective of fuel cell applications, various advanced materials design for catalytic methanol conversion, as well as the development of steam methanol reformers. For the section of utilization pathways, reactions such as steam reforming of methanol, partial oxidation of methanol, oxidative steam reforming of methanol, and sorption-enhanced steam methanol reforming were elaborated;For the catalyst section, the strategies to enhance the catalytic activity and other comprehensive performances were summarized;For the reactor section, the newly designed steam methanol reformers were thoroughly described. This review will benefit researchers from both fundamental research and fuel cell applications in the field of catalyzing methanol to hydrogen.

关键词： methanol reforming hydrogen generation fuel cell catalyst reformer

Characterization of Nanostructures in Acellular Cementum of Human Tooth Roots

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Chemical Research in Chinese Universities 2012年第5期28卷 916-920页

作者： GAO Yong-bo LIU Ming-xia sun zhi-qiang ZHANG Kai DONG Feng-xia sun Hong-chen YANG Bai Department of Oral Pathology School of StomatologyJilin UniversityChangchun 130041P.R.China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012P.R.China

Determining the microstructure in human cementum might help us design new kinds of replacement materials for the treatment of teeth injury and disease. The authors characterized the nanostructures in the cementum of health human teeth via scanning electronic microscopy（SEM）. It was found that the acellular cementum is mainly composed of two kinds of nanostructures―inorganic nanoparticles and organic nanofibers. And the inorganic nanoparticles show a tendency to arrange along the organic nanofibers. Based on the micro-molding in capillary strategy, the distribution of organic component in acellular cementum was copied with UV curable resin. After removing the inorganic nanoparticles by acid etching, many isolated spindle shape nanopores were left in polymer, which su- ggested that the inorganic nanoparticles should have been isolated by the organic component in cementum, and should be oval or nanosheet in shape. We hope the present work could provide reference for the biomimetic preparation of tissue engineering materials, and help us design new types of tooth implant.

关键词： Acellular cementum Nanostructure Root dentin

Blended coals for improved coal water slurries

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Journal of China University of Mining and Technology 2008年第1期18卷 50-54页

作者： GU Tian-ye WU Guo-guang LI Qi-hui sun zhi-qiang ZENG Fang WANG Guang-you MENG Xian-liang School of Chemical Engineering and Technology China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Three coal samples of different ranks were used to study the effect of coal blending on the preparation of Coal Water Slurry (CWS). The results show that by taking advantage of two kinds of coal, the coal concentration in slurry made from hard-to-pulp coal can be effectively improved and increased by 3%–5% generally. DLT coal (DaLiuTa coal mine) is very poor in slurryability and the stability and rheology of the resulting slurry are not very good. When the amount of easily slurried coal is more than 30%, all properties of the CWS improve and the CWS meets the requirements for use as fuel. Coalification, porosity, surface oxygenic functional groups, zeta potential and grindability have a great effect on the performance of blended coal CWS. This leads to some differences in performance between the slurry made from a single coal and slurry made from blended coal.

关键词： low rank coal coal water slurry coal blending slurryability zeta potential

Application of time–frequency entropy from wake oscillation to gas–liquid flow pattern identification

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Journal of Central South University 2018年第7期25卷 1690-1700页

作者： HUANG Si-shi sun zhi-qiang ZHOU Tian ZHOU Jie-min School of Energy Science and Engineering Central South UniversityChangsha 410083China

Gas–liquid two-phase flow abounds in industrial processes and facilities. Identification of its flow pattern plays an essential role in the field of multiphase flow measurement. A bluff body was introduced in this study to recognize gas–liquid flow patterns by inducing fluid oscillation that enlarged differences between each flow pattern. Experiments with air–water mixtures were carried out in horizontal pipelines at ambient temperature and atmospheric pressure. Differential pressure signals from the bluff-body wake were obtained in bubble, bubble/plug transitional, plug, slug, and annular flows. Utilizing the adaptive ensemble empirical mode decomposition method and the Hilbert transform, the time–frequency entropy S of the differential pressure signals was obtained. By combining S and other flow parameters, such as the volumetric void fraction β, the dryness x, the ratio of density φ and the modified fluid coefficient ψ, a new flow pattern map was constructed which adopted S（1–x）φ and （1–β）ψ as the vertical and horizontal coordinates, respectively. The overall rate of classification of the map was verified to be 92.9% by the experimental data. It provides an effective and simple solution to the gas–liquid flow pattern identification problems.

关键词： gas–liquid two-phase flow wake oscillation flow pattern map time–frequency entropy ensemble empirical mode decomposition Hilbert transform

Selection of organic Rankine cycle working fluid based on unit-heat-exchange-area net power

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Journal of Central South University 2015年第4期22卷 1548-1553页

作者：郭美茹朱启的孙志强周天周孑民 School of Energy Science and Engineering Central South University Hunan Key Laboratory of Energy Conservation in Process Industry (Central South University)

To improve energy conversion efficiency, optimization of the working fluids in organic Rankine cycles(ORCs) was explored in the range of low-temperature heat sources. The concept of unit-heat-exchange-area(UHEA) net power, embodying the cost/performance ratio of an ORC system, was proposed as a new indicator to judge the suitability of ORC working fluids on a given condition. The heat exchange area was computed by an improved evaporator model without fixing the minimum temperature difference between working fluid and hot fluid, and the flow pattern transition during heat exchange was also taken into account. The maximum UHEA net powers obtained show that dry organic fluids are more suitable for ORCs than wet organic fluids to recover low-temperature heat. The organic fluid 1-butene is recommended if the inlet temperature of hot fluid is 353.15-363.15 K or443.15-453.15 K, heptane is more suitable at 373.15-423.15 K, and R245 ca is a good option at 483.15-503.15 K.

关键词： organic Rankine cycle(ORC) working fluid selection net power heat exchange area

Flow characteristics at low Reynolds number around two in-line circular cylinders with slits

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Journal of Central South University 2019年第8期26卷 2021-2028页

作者： sun zhi-qiang ZHANG Yu-zhuo XING Peng-fei LI Sai-wei School of Energy Science and Engineering Central South University

This study investigated numerically the characteristics of laminar flow around two identical circular cylinders placed in tandem, with slits of the same width through their respective axis. The center to center distance between the cylinders and the slit orientation were varied to study their effects on the flow structure, lift and drag, and vortex shedding characteristics. It was found that three flow regimes could be distinguished, the transitions between which could be indicated by the sudden changes in drag and lift. Asymmetrically, configured slits destabilized the stagnant region between cylinders;whereas in-line slits connect the two cylinders to act as a single elongated bluff body, even at large cylinder separation, by stabilizing the stagnant region in between. These in turn strongly modified the transition between flow regimes. Vortex shedding was also strongly influenced by both slit configuration and cylinder separation.

关键词： two cylinders in tandem circular cylinder with slit vortex shedding laminar wake flow

大亚湾核电站蒸汽转换器系统给水泵滚动轴承车削拆卸方法探讨

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核科学与工程 2012年第A1期32卷 15-18,70页

作者：孙智强大亚湾核电运营管理有限责任公司维修部广东深圳518124

通过研制专用拉具进行装夹及对车削轴承用刀具、工艺方法等的分析与选择,成功完成了大亚湾核电站蒸汽转换器系统(STR)给水泵中滚动轴承的车削拆卸,可作为核电厂相关的重大、关键零部件加工的参考和借鉴。

关键词：专用拉具装夹给水泵轴承车削拆卸

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气液两相流水平绕流柱体的动态压降特性

高校化学工程学报 2008年第3期22卷 378-383页

作者：孙志强张宏建浙江大学控制科学与工程学系工业控制技术国家重点实验室

压降是气液两相流绕流柱体时包含丰富流动信息的重要参数,对于压降的研究密切关系到两相流动系统的设计和运行。以空气和水为实验介质在泡状流、塞状流、弹状流和环状流四种流型下,研究了气液两相流水平绕流梯形柱体的动态压降特性。结... 详细信息

压降是气液两相流绕流柱体时包含丰富流动信息的重要参数,对于压降的研究密切关系到两相流动系统的设计和运行。以空气和水为实验介质在泡状流、塞状流、弹状流和环状流四种流型下,研究了气液两相流水平绕流梯形柱体的动态压降特性。结果表明:泡状流和塞状流的动态压降有较稳定的波动,其时均值主要取决于液相流量;弹状流的动态压降变化剧烈,其时均值随两相雷诺数的分布比较均匀;环状流的动态压降变化比较平缓,其时均值随两相雷诺数的增加呈近似线性递增;在四种不同流型下,时均动态压降系数随两相雷诺数的增加都呈线性递减。这一结果为分析气液两相流绕流柱体的流动特性提供了有益的借鉴。

关键词：气液两相流柱体绕流压降动态特性

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禁止特设性假说:对一个方法论原则的考察

科学技术与辩证法 2005年第3期22卷 34-38页

作者：胡志强中国科学院研究生院社科系北京100049

对于假说演绎法、证伪主义和科学研究纲领方法论,禁止特设性假说都是一个重要的方法论原则。但对于什么是特设性假说的标准,特设性原则是否是一个独立的方法论原则,还存在相当多的争议。文章试图梳理几种重要的关于特设性假说的看法,用... 详细信息

对于假说演绎法、证伪主义和科学研究纲领方法论,禁止特设性假说都是一个重要的方法论原则。但对于什么是特设性假说的标准,特设性原则是否是一个独立的方法论原则,还存在相当多的争议。文章试图梳理几种重要的关于特设性假说的看法,用以表明对科学合理性认识中的复杂因素。

关键词：特设性假说评价方法论原则