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Morphology Structure Evolution and Combustion Reactivity of Bituminous Char at Around Ash Melting Temperature

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Journal of Thermal Science 2022年第6期31卷 2189-2202页

作者： ZHANG Yandi YANG Huan WANG Bo HMShahzaib KHAN DUAN Xiaoli liu yinhe State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi'an Jiaotong UniversityXi'an 710049China

In slag tapping furnaces, char particles undergo a series of complex structural evolution before and after being captured by the liquid slag layer. The evolution results affect the carbon conversion rate and are affected by temperature fluctuations, especially in the ash melting temperature zone. Experimental study on structure evolution of bituminous char prepared at around ash melting temperature was carried out on a fixed bed. The morphology, specific surface area and mineral chemical composition were measured at different temperatures. Experimental results show that the number density and the size of ash droplets exuded on the char surface increased significantly with the increasing temperature. The ash specific surface area from gasification was slightly greater than that from combustion. The residual content of chloride in the char become 1% and the contents of Fe, K, Mg and Na decrease significantly during the pyrolysis process across the ash melting temperature zone. The diffraction intensity of oldhamite increase which indicates the reaction of carbon substrate with minerals during the evolution;the diffraction intensity of quartz dramatically decreases for the reason of anorthite generation. The ignition and burnout temperatures of char were found to increase and the combustion stability decreased with the increasing pyrolysis temperature.

关键词： coal char structure evolution carbothermal reaction combustion

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电气化甲烷重整技术研究进展

低碳化学与化工 2024年第4期49卷 1-11页

作者：宋虎潮边浩林啸龙沈孟飞王舒曼刘银河西安交通大学能源与动力工程学院动力工程多相流国家重点实验室陕西西安710049

甲烷重整是强吸热反应,通过燃烧甲烷供热(约占甲烷总消耗的30%),不仅会导致排烟热损失,还会伴随CO_(2)排放,无法满足双碳目标下对清洁氢能的需求。电气化甲烷重整技术通过高效电热转化形式,将可再生电能引入甲烷重整反应器,可大幅减少... 详细信息

甲烷重整是强吸热反应,通过燃烧甲烷供热(约占甲烷总消耗的30%),不仅会导致排烟热损失,还会伴随CO_(2)排放,无法满足双碳目标下对清洁氢能的需求。电气化甲烷重整技术通过高效电热转化形式,将可再生电能引入甲烷重整反应器,可大幅减少甲烷重整过程的CO_(2)排放,消除传统甲烷重整过程的排烟热损失,提升甲烷和可再生电能制氢效率。综述了传统甲烷重整技术、电气化甲烷重整反应器(电阻加热、微波加热、电磁感应加热和等离子体加热)、电气化甲烷重整系统和电气化甲烷重整催化剂的研究进展。电加热不仅可以有效提升反应器功率密度、减小反应器规模,还可以通过与催化剂相互作用,实现催化活性和甲烷转化率的提升。电气化甲烷重整技术为我国能源绿色低碳转型提供了新的途径。

关键词：电气化甲烷重整清洁氢能反应器催化剂

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Paleo-Environment Reconstruction of the Middle Permian Lucaogou Formation,Southeastern Junggar Basin,NW China:Implications for the Mechanism of Organic Matter Enrichment in Ancient Lake

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Journal of Earth Science 2022年第4期33卷 963-976页

作者： Dawei Cheng Chuanmin Zhou Zhijie Zhang Xuanjun Yuan yinhe liu Xingyu Chen Research Institute of Petroleum Exploration and Development PetroChinaBeijing 100083China School of Earth and Space Sciences Peking UniversityBeijing 100871China

The Middle Permian Lucaogou Formation is the source rock and the main oil shale producing formation in the southeastern Junggar *** study focused on the Lucaogou Formation exposed in two outcrop sections on the northern flank of the Bogda Mountain,namely the Jingjingzigou and Dalongkou ***,we present integrated analysis of the sedimentology,major and trace elements,mineral components and total organic carbon *** paleo-environment was reconstructed including provenance,redox conditions,paleo-salinity,chemical weathering intensity and primary organic matter *** results showed that the upper and lower units were deposited in distinct depositional environments with different organic matter accumulation *** lower unit was characterized by low lake level,dry climate,fresh-brackish and well-oxygenated *** during the deposition of the upper unit the lake level rose,climate turned wetter and the bottom water became less oxidized and much *** mechanism of the organic matter accumulation is different for these two *** preserved organic matters were mainly controlled by the primary productivity in the lower unit and by the redox conditions in the upper unit.

关键词： trace element redox condition paleosalinity primary productivity chemical weathering

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碳基燃料燃烧的温室气体在线监测实验

实验室科学 2024年第1期27卷 45-48,53页

作者：张锦萍陈昊煊刘银河西安交通大学能源与动力工程学院陕西西安710049

为加深学生对“双碳”理念和碳基燃料清洁高效利用技术的理解,设计了半焦及烟煤两种燃料燃烧的温室气体在线监测实验。模拟燃煤锅炉工况,搭建燃烧反应系统,采用便携式傅里叶红外气体分析仪研究碳基燃料燃烧的温室气体释放特征。结果表明... 详细信息

为加深学生对“双碳”理念和碳基燃料清洁高效利用技术的理解,设计了半焦及烟煤两种燃料燃烧的温室气体在线监测实验。模拟燃煤锅炉工况,搭建燃烧反应系统,采用便携式傅里叶红外气体分析仪研究碳基燃料燃烧的温室气体释放特征。结果表明,CH_(4)与CO_(2)、N_(2)O的起始和终止释放时间不同,单位质量半焦和烟煤释放出的CO_(2)量均远高于CH_(4)和N_(2)O的释放量;燃烧温度升高,CO_(2)释放量均先升高后降低,CH_(4)和N_(2)O的释放量逐渐降低;1000℃以上燃烧时,半焦释放的CO_(2)较多,CH_(4)较少,两种燃料的N_(2)O释放量都接近0。该综合实验中,教师以学科前沿知识为基奠,引导学生自主实践,旨在于培养学生分析解决问题的能力,提升学生的工程实践综合素质。

关键词：碳基燃料燃烧温室气体在线监测综合实验

Multi-temporal urban semantic understanding based on GF-2 remote sensing imagery:from tri-temporal datasets to multi-task mapping

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International Journal of Digital Earth 2023年第1期16卷 3321-3347页

作者： Sunan Shi Yanfei Zhong yinhe liu Jue Wang Yuting Wan Ji Zhao Pengyuan Lv Liangpei Zhang Deren Li State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanPeople’s Republic of China Hubei Provincial Engineering Research Center of Natural Resources Remote Sensing Monitoring Wuhan UniversityWuhanPeople’s Republic of China College of Computer Science China University of GeosciencesWuhanPeople’s Republic of China School of Information Engineering Ningxia UniversityYinchuanPeople’s Republic of China

High resolution satellite images are becoming increasingly available for urban multi-temporal semantic ***,few datasets can be used for land-use/land-cover(LULC)classification,binary change detection(BCD)and semantic change detection(SCD)simultaneously because classification datasets always have one time phase and BCD datasets focus only on the changed location,ignoring the changed *** SCD datasets are rare but much *** solve the above problems,a tri-temporal SCD dataset made up of Gaofen-2(GF-2)remote sensing imagery(with 11 LULC classes and 60 change directions)was built in this study,namely,the Wuhan Urban Semantic Understanding(WUSU)*** deep learning based methods for LULC classification,BCD and SCD are tested to verify the reliability of WUSU.A Siamese-based multi-task joint framework with a multi-task joint loss(MJ loss)named ChangeMJ is proposed to restore the object boundaries and obtains the best results in LULC classification,BCD and SCD,compared to the state-of-the-art(SOTA)***,a large spatial-scale mapping for Wuhan central urban area is carried out to verify that the WUsU dataset and the ChangeMJ framework have good application values.

关键词： GF-2 remote sensing imagery multi-temporal satellite datasets urban LULC mapping binary and semantic change detection multi-task framework

Regioselective and asymmetric allylic alkylation of vinyl epoxides for the construction of allylic alcohols via synergistic catalysis

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Science China Chemistry 2024年第2期67卷 542-550页

作者： Min Chen Longqing Yang Yuzhen Li yinhe Qu Guihua Pan Xiaoming Feng Xiaohua liu Key Laboratory of Green Chemistry&Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengdu610064China

A highly efficient asymmetric allylic alkylation of cyclic and acyclic carbon nucleophiles with vinyl epoxides has been developed,which exhibits good functional group compatibility,high atomic and step *** protocol utilizes a strategy of synergistic catalysis with a chiral N,N'-dioxide/Ni~Ⅱ complex and an achiral Pd~0 catalyst,generating a series of multisubstituted allylic alcohols with a quaternary carbon stereocenter in high yield and excellent regio-,Z/E-and enantioselectivity under mild *** transformations of the product demonstrate the potential utility of this protocol in the synthesis of allyl alcohol derivatives and natural product *** studies revealed that the N,N′-dioxide/metal complexes play an important role in controlling the Z/E-and *** density functional theory(DFT) calculations further demonstrated that multiple C–H···π interactions between the aromatic rings of the two substrates and the amide moiety in the ligand stabilized the dominant transition state.

关键词： asymmetric allylic alkylation synergistic catalysis vinyl epoxides allyl alcohol multiple weak interactions

Effect of temperature on Lu’an bituminous char structure evolution in pyrolysis and combustion

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Frontiers in Energy 2021年第1期15卷 14-25页

作者： Yandi ZHANG yinhe liu Xiaoli DUAN Yao ZHOU Xiaoqian liu Shijin XU State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

In the process of pyrolysis and combustion of coal particles, coal structure evolution will be affected by the ash behavior, which will further affect the char reactivity, especially in the ash melting temperature zone. Lu’an bituminous char and ash samples were prepared at the N_(2) and air atmospheres respectively across ash melting temperature. A scanning electron microscope (SEM) was used to observe the morphology of char and ash. The specific surface area (SSA) analyzer and thermogravimetric analyzer were respectively adopted to obtain the pore structure characteristics of the coal chars and combustion parameters. Besides, an X-ray diffractometer (XRD) was applied to investigate the graphitization degree of coal chars prepared at different pyrolysis temperatures. The SEM results indicated that the number density and physical dimension of ash spheres exuded from the char particles both gradually increased with the increasing temperature, thus the coalescence of ash spheres could be observed obviously above 1100℃. Some flocculent materials appeared on the surface of the char particles at 1300℃, and it could be speculated that β-Si_(3)N_(4) was generated in the pyrolysis process under N_(2). The SSA of the chars decreased with the increasing pyrolysis temperature. Inside the char particles, the micropore area and its proportion in the SSA also declined as the pyrolysis temperature increased. Furthermore, the constantly increasing pyrolysis temperature also caused the reactivity of char decrease, which is consistent with the results obtained by XRD. The higher combustion temperature resulted in the lower porosity and more fragments of the ash.

关键词： bituminous char pyrolysis ash structure evolution reactivity

Application of Multifocusing Method for an Irregular Topography Imaging

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Journal of China University of Geosciences 2005年第3期16卷 256-261页

作者： Luo yinhe liu Jiangping Yao Yao Institute of Geophysics ＆ Geomatics China University of Geosciences Wuhan 430074 China

A stack of records becomes one of the main steps in modern seismic data processing. In the stack procedure, the crucial operation is time correction. Conventional methods, e.g. , normal moveout （NMO） and dip moveout （DMO） stacks require a sufficiently accurate macro-velocity model, whereas a multifocusing imaging method does not depend on a macro-velocity model. The multifocusing method proposed by Gelchinsky et al. belongs to a group of methods that can be characterized as macro-model-independent imaging methods. The multifocusing method represents a transformation of 2-D multicoverage reflection data into a simulated zero-offset stack profile. This transformation is based on a completely data-derived spatial stacking operator, and includes stacking large supergathers of seismic traces, each of which can span many CMP gathers. By extending the multifocusing moveout formula to explicitly account for non-zero elevations of the source and receiver, the multifocusing imaging method can yield appropriate results when seismic data are acquired over an irregular topography. In recent years, many applications of multifocusing imaging over an irregular topography have demonstrated its advantages in comparison with conventional CMP processing. This paper illustrates the corresponding formulas for a synthetic data example modeled by the wave equation finite difference method. The result of the synthetic example is very encouraging. By stacking large supergathers and applying multifocusing moveout correction, the reflectors are aligned very well and the S/N is greatly improved. We have also applied multifocusing imaging over an irregular topography to a real data example. The elevation of the data acquisition area varies considerably. Applying multifocusing imaging, a substantial improvement of the simulated section was achieved, compared with a conventional CMP stacked section.

关键词： time correction multifocusing imaging topography

Reconstruction of the adenosine system by bone marrow-derived mesenchymal stem cell transplantation

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Neural Regeneration Research 2012年第4期7卷 251-255页

作者： Huicong Kang Qi Hu Xiaoyan liu yinhe liu Feng Xu Xiang Li Suiqiang Zhu Department of Neurology Tongji Hospital of Tongji Medical University Huazhong University of Science and Technology Wuhan 430030 Hubei Province China Ministry of Water Resources of China Beijing 100000 China

In the present study, we transplanted bone marrow-derived mesenchymal stem cells into the CA3 area of the hippocampus of chronic epilepsy rats kindled by lithium chloride-pilocarpine, Immunofluorescence and western blotting revealed an increase in adenosine A1 receptor expression and a decrease in adenosine A2a receptor expression in the brain tissues of epileptic rats 3 months after transplantation. Moreover, the imbalance in the A1 adenosine receptor/A2a adenosine receptor ratio was improved. Electroencephalograms showed that frequency and amplitude of spikes in the hippocampus and frontal lobe were reduced. These results suggested that mesenchymal stem cell transplantation can reconstruct the normal function of the adenosine system in the brain and greatly improve epileptiform discharges.

关键词： bone marrow-derived mesenchymal stem cells chronic epilepsy cell transplantation reconstruction adenosine system electroencephalogram immunohistochemistry