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智慧城市试点政策如何影响区域协同创新

公共管理与政策评论 2024年第5期13卷 26-45页

作者：种照辉位晓琳覃成林汕头大学商学院江西财经大学经济学院暨南大学经济学院

区域协同创新是实现中国式现代化的重要支撑。本文基于中国2008-2018年276个城市的面板数据,以国家智慧城市试点政策为准自然实验,考察了智慧城市的协同创新效应及其影响机制。研究发现,智慧城市试点政策显著促进了城市间的协同创新,具... 详细信息

区域协同创新是实现中国式现代化的重要支撑。本文基于中国2008-2018年276个城市的面板数据,以国家智慧城市试点政策为准自然实验,考察了智慧城市的协同创新效应及其影响机制。研究发现,智慧城市试点政策显著促进了城市间的协同创新,具体而言,智慧城市试点政策使试点城市的城市间专利合作数(每万人)提高约0.479个。本地创新能力提升和高新技术产业发展是智慧城市促进区域协同创新的两个重要机制。进一步分析发现,智慧城市试点政策对区位条件好的城市影响更大,同时,这一影响也与城市规模的大小有关。本文为智慧城市试点政策在全国范围内进一步推广提供了重要参考,并为强化区域协同创新提供了新的思路。

关键词：智慧城市试点政策协同创新创新能力提升高新技术产业发展双重差分

基于FES技术的O_(2)/CO_(2)燃烧气氛下准东煤中不同类型碱金属盐的释放特性

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煤炭学报 2024年第7期49卷 3216-3224页

作者：赵京杨本超魏小林倪文翔乔瑜娄春中国科学院力学研究所高温气体动力学国家重点实验室北京100190 西安交通大学能源与动力工程学院陕西西安710049 华中科技大学煤燃烧国家重点实验室湖北武汉430074

O_(2)/CO_(2)燃烧技术被认为是一种清洁的燃煤发电技术,然而高碱准东煤燃烧过程中释放的大量碱金属通常是引起锅炉受热面积灰、结渣以及腐蚀的重要物质,严重危害了设备的安全稳定运行。因此,探讨O_(2)/CO_(2)燃烧气氛下准东煤中不同类... 详细信息

O_(2)/CO_(2)燃烧技术被认为是一种清洁的燃煤发电技术,然而高碱准东煤燃烧过程中释放的大量碱金属通常是引起锅炉受热面积灰、结渣以及腐蚀的重要物质,严重危害了设备的安全稳定运行。因此,探讨O_(2)/CO_(2)燃烧气氛下准东煤中不同类型碱金属盐的释放特性对于煤炭的清洁高效利用具有重要意义。基于火焰发射光谱技术(FES),在金属丝网反应器上研究了煤粉燃烧过程中不同类型碱金属盐在O_(2)/N_(2)和O_(2)/CO_(2)两种气氛下的释放特性。结果表明:在O_(2)/N_(2)气氛下,挥发分燃烧会产生明亮的火焰;与O_(2)/N_(2)气氛相比,O_(2)/CO_(2)气氛下煤粉燃烧强度降低,火焰温度下降,着火时间延迟,挥发分和焦炭的燃烧时间延长,使得煤粉中气相Na的释放过程受到抑制。对于NaAc、Na_(2)CO_(3)和Na_(2)SO_(4)来讲,O_(2)/CO_(2)气氛延迟了其释放过程中质量浓度降低的时间,使煤粉中气相Na从开始释放就进入稳定释放阶段,气相Na质量浓度变化率波动不大;但NaCl会在释放的4 s左右质量浓度变化率变为负值,导致释放的气相Na质量浓度一直降低。同时CO_(2)气氛还会使得NaAc、NaCl等类型盐转化形成更难释放的Na_(2)CO_(3),进一步抑制气相Na的释放过程。而Na_(2)CO_(3)的质量释放率在O_(2)/CO_(2)气氛下也降低的主要原因则是CO_(2)抑制了Na_(2)CO_(3)向Na_(2)O的分解过程。Na_(2)SO_(4)则由于其本身释放就比较困难,因此其质量释放率降低的主要原因是燃料燃烧温度和强度降低导致的。

关键词： O_(2)/CO_(2)燃烧碱金属火焰发射光谱技术金属丝网反应器释放特性

高压变频节能改造技术在煤矿主通风机中的应用

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中国高新科技 2024年第1期 70-72页

作者：位晓林山东能源集团枣庄矿业(集团)有限责任公司田陈煤矿山东枣庄277000

主通风机是煤矿的主要设备之一,部分煤矿在开采后期主通风机的运行功率远超出煤矿正常生产所需运行功率,能量损耗较为严重。基于此,文章针对煤矿主通风机高压变频节能改造需求,提出了煤矿主通风机高压变频节能改造方案。经实践分析,煤... 详细信息

主通风机是煤矿的主要设备之一,部分煤矿在开采后期主通风机的运行功率远超出煤矿正常生产所需运行功率,能量损耗较为严重。基于此,文章针对煤矿主通风机高压变频节能改造需求,提出了煤矿主通风机高压变频节能改造方案。经实践分析,煤矿主通风机高压变频节能改造效果较好,实现了提质增效的目的。

关键词：高压变频节能技术主通风机

Experimental Investigation on Flame Characterization and Temperature Profile of Single/Multiple Pool Fire in Cross Wind

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Journal of Thermal Science 2021年第1期30卷 324-332页

作者： CHEN Zhen wei xiaolin LI Teng Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China State Key Laboratory of High Temperature Gas Dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

An experimental study was carried out to investigate the flame characterization and temperature profile for single and multiple pool fire with the influence of cross *** were 13 test cases in total,categorized into circle and rectangle fuel pans,with diameter(or equivalent diameter)ranged from 50 mm to 300 *** was used for the fuel of pool *** K-type thermocouples were arranged around the flame to monitor the flame temperature,while the flame tilt angle was measured based on the photograph of flame for different ***,it can be found that there are three phases,including preheating,steady burning and extinguishing phase,during the flame *** maximum temperature near the fuel surface is~1040 K,which is higher than that of flame plume(~600 K),in the steady burning phase of circle single pool fire(D=300 mm),while the average burning rate is~1.525 g/*** addition,the burning rates of all cases were measured and compared with the current predicted ***,the flame morphology of single/multiple pool fire at different cross wind speed(ranging from 0 to 3.5 m/s)was analyzed,and it is found that the results for single pool fire agree with Thomas model and AGA model well,which are not suitable for multiple pool ***,the temperature profile of different case was measured with various wind speed.

关键词： pool fire temperature profile flame characteristic kerosene cross wind

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基于以太网和PLC的轴监控系统设计

自动化与仪表 2024年第5期39卷 109-112,136页

作者：魏小林钱厚亮魏宇君江苏联合职业技术学院南京工程分院南京211135 南京工程学院工业中心南京211167 南京林业大学机械电子工程学院南京210037

为监控生产现场离散单机设备中各运动轴的运行情况,掌握设备运行时伺服轴的必要参数数据,实现对设备的高效及智能化管理与维护,设计构建了一种基于以太网及云平台的远程轴监控系统。系统由PLC和运动控制模块、工业交换机、触摸屏、上位... 详细信息

为监控生产现场离散单机设备中各运动轴的运行情况,掌握设备运行时伺服轴的必要参数数据,实现对设备的高效及智能化管理与维护,设计构建了一种基于以太网及云平台的远程轴监控系统。系统由PLC和运动控制模块、工业交换机、触摸屏、上位机、云平台等构成;通过Modbus TCP协议建立上位机与设备的以太网通道,实现上位机PC端与手机端对设备轴的远程监控;采用SQLite数据库将轴数据保存,实现数据的分析和再利用。经实验系统实现了对设备运行的远程实时监控,系统运行稳定,可应用在智能制造的自动化装备和生产中。

关键词：以太网 PLC 轴监控 SQLite数据库

含钨粉体改性三维间隔连体织物复合材料γ射线屏蔽性能研究

同方期刊数据库博看期刊评论

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复合材料科学与工程 2024年第8期 24-31页

作者：刘雨舜魏筱霖刘奔奔顾轶卓中国航空制造技术研究院复合材料技术中心北京101300 北京航空航天大学材料科学与工程学院北京100191 北京航空航天大学前沿科学技术创新研究院北京100191

核能会产生电离辐射,如X,γ射线,需采用屏蔽材料进行防护。传统的X射线和γ射线屏蔽材料存在重量大、易腐蚀、有毒和结构力学性能低等缺点,因此研制质轻、辐射性能优异、结构/功能一体化的新型复合材料是辐射防护技术发展的重要方向。... 详细信息

核能会产生电离辐射,如X,γ射线,需采用屏蔽材料进行防护。传统的X射线和γ射线屏蔽材料存在重量大、易腐蚀、有毒和结构力学性能低等缺点,因此研制质轻、辐射性能优异、结构/功能一体化的新型复合材料是辐射防护技术发展的重要方向。根据各类含钨粉体的质量衰减系数理论计算值及密度,优选了氧化钨作为γ射线屏蔽填料,采用含钨粉体改性环氧树脂,并与玻璃纤维三维间隔连体织物复合形成具有夹层结构的纤维增强复合材料。考察了不同含量氧化钨对复合材料屏蔽60Co和137Csγ射线的能力及平压性能的影响。实验结果表明:氧化钨粉对复合材料的辐射屏蔽性能有显著的提升,提升程度与理论计算值相近;相同屏蔽率下,复合材料重量明显低于铁的重量;此外氧化钨也提高了连体织物复合材料的平压强度和平压模量。

关键词：树脂基复合材料氧化钨粉三维间隔连体织物 γ射线辐射屏蔽

Experimental Investigation on the Performance of[APMIm][NTf_(2)]for Capturing CO_(2)from Flue Gas of the Cement Kiln Tail

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Journal of Thermal Science 2021年第5期30卷 1780-1788页

作者： PAN Lisheng SHI weixiu LI Bing wei xiaolin State Key Laboratory of High-temperature Gas Dynamics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Environment and Energy Engineering Beijing University of Civil Engineering and ArchitectureBeijing100044China School of Engineering Sciences University of Chinese Academy of SciencesBeijing100049China

Facing the global warming trend,humanity has been paying more and more attention to the Carbon Capture,Utilization and *** amounts of CO_(2)is emitted with burning fossil fuel as well as by some special industrial processes like the decomposition of calcium carbonate in a cement *** cement industry contributes about 7%of the total worldwide CO_(2)emissions and the CO_(2)concentration of flue gas of the cement kiln tail even exceeds 30%.Ionic liquid is considered to be an effective and potential material to capture CO_(2).In order to investigate the performance of ionic liquids for capturing CO_(2)from flue gas of the cement kiln tail,an experiment system was established and an ionic liquid,[APMIm][NTf_(2)](1-aminopropyl-3-imidazolium bis(trifluoromethylsulfonyl)imine),was tested using pure CO_(2)and simulated *** results showed that both physical and chemical absorption play roles while physical absorption dominates in the absorption *** the absorption capacity and rate decrease with raising the operating *** the experiment with pure CO_(2),the absorption capacity is 0.296molCO_(2)⋅molIL−1 at 30℃ and 0.067molCO_(2)⋅molIL−1 at 70℃.Meanwhile,the ionic liquid can be regenerated for recycling without obvious changes of the absorption *** the ionic liquid is used for flue gas of the cement kiln tail rather than pure CO_(2),a sharp decrease of the absorption capacity and rate was observed *** absorption capacity at 30℃ dropped even to 0.038molCO_(2)⋅mol_(IL)^(−1),12.8%of that for pure CO_(2).Additionally,a natural desorption of CO_(2)from the ionic liquid was observed and affected the experimental results of the absorption capacity and the absorption-desorption rate to some extent.

关键词： ionic liquid CO_(2)absorption Carbon Capture Utilization and Storage(CCUS) flue gas of the cement kiln tail

Modeling De-No_(x) by Injection Ammonia in High Temperature Zone of Cement Precalciner

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Journal of Thermal Science 2021年第2期30卷 636-643页

作者： ZHANG Leyu wei xiaolin ZHANG Zhongxiao LI Sen Institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100190China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai 200093China

The quantity of NO_(x) emission from cement production is second only to thermal power generation and vehicle *** this paper,a phenomenon found by Taniguchi is used to achieve NO_(x) reduction in the cement *** on his results,it is proposed to reduce NO_(x) that ammonia is injected in the high-temperature and lean-oxygen zone(HT-DeNO_(x))during pulverized coal *** a large cement precalciner(3200 t/d),numerical simulation is used to evaluate the technology of HT-DeNO_(x) combined with the traditional selective non-catalytic reduction(SNCR)*** results indicate that NH3 and HCN in HT-DeNO_(x) can reduce NO during the reaction *** very little ammonia injection(normalized stoichiometric ratio NSR=0.1,the normalized stoichiometric ratio),the efficiency of NO reduction by HT-DeNO_(x) is 27.72%.Combining SNCR(NSR=1.1)and HT-DeNO_(x)(NSR=0.1),the reduction efficiency will be improved to 60.05%,compared with 50.83%efficiency when using only SNCR at NSR=1.2.

关键词： cement precalciner coal combustion CaCO_(3) decomposition high temperature zone SNCR

Prediction of remnant volatile matter in the semicokes from coal partial gasification

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Science China(Technological Sciences) 2011年第11期54卷 3017-3021页

作者： LIU DianFu wei xiaolin SHENG HongZhi Department of Thermal Engineering Anhui University of Technology Ma＇anshan 243002 China Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The semicokes from different coals were prepared under various temperatures by partial gasification method in a fixed bed. According to the analysis of the Vaaf in the coals and semicokes, a new method is presented to predict the content of remnant volatile matter in the semicokes from coal partial gasification. The two fuel character indexes FV and FC were introduced to symbolize the second volatilized temperature and the fully volatilized temperature respectively. Then according to the proximate and ultimate analysis data of raw coal, the content of Vdaf in the semicokes prepared under various temperatures can be predicted.

关键词： partial gasification semicokes content of volatile matter