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Gas-solid Flow Characteristics in High-density CFB

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Journal of Thermal Science 2012年第4期21卷 354-358页

作者： Xue-yao Wang Bao-guo Fan Sheng-dian Wang Xiang Xu Yun-han Xiao Research Center for Clean Energy and Power Chinese Academy of SciencesKey Laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

The gas-solid flow characteristics in the riser of a high density CFB of square (0.27 m×0.27 m×10.4 m) or circu-lar (? 0.187m×10.4 m) cross section, using Geldart B particles (quartz sand), was investigated experimentally. The influence of riser structure on the hydrodynamic behaviors of a high-density circulating fluidized bed was investigated. The solid circulation rate was up to 321 kg/(m2s) with the circular cross-section under the operating conditions of the main bed air velocity 12.1 m/s and loosen wind and back-feed wind flow 25.1 m3/h. Different operating conditions on realizing high density circulation was analyzed, while both solids circulation rate and particle holdup depended highly on operating conditions. The circulating gas-solid flow was accompanied by an evidently-dense character in the riser's bottom zone and became fully developed in the middle and upper zones.

关键词： HDCFB gas-solid flow solids circulation rate

潮白河北京段着生藻类群落结构及其优势种生态位特征

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环境工程技术学报 2024年第1期14卷 52-59页

作者：盛祥锐罗遵兰孙光肖能文康玲玲李慧清韩静中国环境科学研究院兰州大学生态学院

为明确北京市潮白河流域浮游植物群落变化特征,于2021年5月和9月对潮白河17个样点的着生藻类进行调查。应用着生藻类种类数和细胞密度对群落结构进行分析,计算优势种的优势度指数(Y)、优势种更替率(R),运用生态位宽度(Bi)、生态位重叠指... 详细信息

为明确北京市潮白河流域浮游植物群落变化特征,于2021年5月和9月对潮白河17个样点的着生藻类进行调查。应用着生藻类种类数和细胞密度对群落结构进行分析,计算优势种的优势度指数(Y)、优势种更替率(R),运用生态位宽度(Bi)、生态位重叠指数(O_(ik))、总体相关性分析优势种的生态位特征。结果表明:2次调查共鉴定着生藻类109种,隶属4门41属,着生藻类优势种(Y>0.2)共8种,优势种的生态位宽度为0.1406~0.4209,优势种的生态位重叠指数为0.0551~0.8971,总体关联性测度结果均为显著正关联,优势种受季节更替的影响较大,优势种间对资源的利用共性较小,着生藻类群落结构趋于稳定,整体朝正向演替发展。研究表明,着生藻类作为一项生物指标对环境条件的变动能够进行较为敏感的响应,基于着生藻类优势种生态位特征,能够对着生藻类群落结构及其演替特征进行描述。

关键词：潮白河着生藻类群落结构生态位

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住宅运行阶段碳排放智能监测控制系统设计

智能建筑与智慧城市 2024年第1期 94-96页

作者：苗泽惠韩光伟吉林建筑大学

随着“双碳”目标的提出,住宅运行阶段的高能耗、高碳排放等问题亟待解决。文章构建了一种从外部环境端、供给端、输送端、需求端出发,以感知层、传输层、控制层和应用层为基础架构,面向住宅碳排放公共、私人区域特点与能源供需关系更... 详细信息

随着“双碳”目标的提出,住宅运行阶段的高能耗、高碳排放等问题亟待解决。文章构建了一种从外部环境端、供给端、输送端、需求端出发,以感知层、传输层、控制层和应用层为基础架构,面向住宅碳排放公共、私人区域特点与能源供需关系更为精细化的碳排放智能监测控制系统,解决了住宅在运行阶段能耗与碳排放的智能监测和控制问题。该系统综合考虑了运行过程中外部环境、供应端、内部传输端与需求端的动态变化,针对住宅的特点提出了分级差异化控制模式、相应的技术措施和系统架构,设计了合理的用能管理和碳排放优化控制策略,以实现低能耗、低碳排放且满足使用需求条件下住宅的正常运行,在提高管理效率与智能化水平的同时,降低住宅运行阶段的能耗与碳排放量。

关键词：住宅运行阶段碳排放控制

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基于响应面法的钒钛铁尾矿基地聚物配比优化

金属矿山 2024年第9期 275-282页

作者：聂少君韩秀丽刘磊孟广安邹玄王玲华北理工大学矿业工程学院河北唐山063210 矿产资源绿色开发与生态修复协同创新中心河北唐山063210 河北省矿业开发与安全技术实验室河北唐山063210 河北省地质矿产研究中心河北石家庄050051 河钢集团国际物流有限公司矿业分公司河北石家庄050051

为促进钒钛铁尾矿高质量、规模化地有效利用,以钒钛铁尾矿为主要原料制备地聚物胶凝材料,采用响应面法Central Composite Design设计,研究n(SiO_(2))/n(Al_(2)O_(3))、Na_(2)CO_(3)掺量和液固比对地聚物抗压强度的影响并揭示强度形成机... 详细信息

为促进钒钛铁尾矿高质量、规模化地有效利用,以钒钛铁尾矿为主要原料制备地聚物胶凝材料,采用响应面法Central Composite Design设计,研究n(SiO_(2))/n(Al_(2)O_(3))、Na_(2)CO_(3)掺量和液固比对地聚物抗压强度的影响并揭示强度形成机理,通过构建回归模型探究各因素对抗压强度的影响程度,以获得性能最佳配比。结果表明,n(SiO_(2))/n(Al_(2)O_(3))对地聚物抗压强度影响最大,液固比影响最小,且三者之间存在一定交互作用。钒钛铁尾矿与偏高岭土在碳酸钠激发作用下发生了聚合反应与水化反应,生成N—A—S—H凝胶与C—S—H凝胶等,同时钒钛铁尾矿的微集料效应对地聚物抗压强度也有一定贡献,故地聚物强度形成主要来自胶凝体与集料间紧密交织组成的致密结构。当n(SiO_(2))/n(Al_(2)O_(3))=2.7,Na_(2)CO_(3)掺量55%,液固比0.25m L/g时,地聚物抗压强度预测值为51.769MPa,试验值为50.320MPa,相对误差在合理范围内,证实了响应面法能有效优化配比并具有较好的预测能力。

关键词：钒钛铁尾矿地聚物响应面法配比交互作用

室外广域环境下移动机器人地形障碍检测及分析方法

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科学技术与工程 2024年第19期24卷 8150-8157页

作者：韩广涛张明路高春艳吕晓玲河北工业大学机械工程学院天津300401

近年来,移动机器人已广泛应用于应急救援、公共安防、巡检探测等多个领域。在机器人移动过程中,环境感知能力尤为重要,尤其在包含动态、未知以及复杂因素干扰的室外广域工作场景中,障碍物检测极大影响机器人的功能及效率。针对地面移动... 详细信息

近年来,移动机器人已广泛应用于应急救援、公共安防、巡检探测等多个领域。在机器人移动过程中,环境感知能力尤为重要,尤其在包含动态、未知以及复杂因素干扰的室外广域工作场景中,障碍物检测极大影响机器人的功能及效率。针对地面移动机器人在此类场景下对障碍物检测的研究进展进行了对比,并根据障碍物的特征对正、负障碍检测方法进行了分析;进而概述了信息融合和深度学习在当前领域的应用现状;最后,总结了障碍物检测领域的研究现状,并指出相关技术的探索方向。

关键词：移动机器人非结构化场景障碍物检测信息融合深度学习

Crystallization Temperature and Crystallization Ratio of Mold Flux

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Journal of Iron and Steel Research International 2005年第6期12卷 23-26页

作者： ZHU Chuan-yun han Wen-dian LIU Cheng-jun JIANG Mao-fa Northeastern University Shenyang 110004 China Central Iron and Steel Research Institute Beijing 100081 China

The factors influencing the crystallization ratio of mold flux were researched by rapid cooling technolo gy, and the factors affecting crystallization temperature were studied by single thermocouple technique. The results showed that the crystallization ratio of mold flux increases with the basicity and the content of Na2O, CaF2, Li2O and NaF, and decreases with the increase of the content of Al2O3, MgO, BaO, MnO and B2O3. However, the crystallization temperature of mold flux rises with the basicity and the content of NaF, Na2O and CaF2, and reduces with the increase of the content of Al2O3, MgO, BaO, MnO and B2O3. But for Li2O, crystallization temperature decreases firstly to a minimum value at 2%, and then increases gradually with the increase of Li2O.

关键词： mold flux crystallization temperature crystallization ratio viscosity solidification temperature

Influence of Solution Treatment on Microstructure of AEREX350 Alloy

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Journal of Iron and Steel Research International 2010年第3期17卷 67-71页

作者： WAN Wen-juan han guang-wei DENG Bo Department of High Temperature Materials Research Central Iron and Steel Research Institute Beijing 100081 China

The microstructure of hot rolled AEREX350 alloy under various solution treatments was investigated by scanning electron microscope （SEM） and transmission electron microscope （TEM）. It was found that with increasing solution temperature, η phase precipitated firstly at grain boundaries in parallel at 800 ℃ and then within grains at about 980 ℃. The η phase precipitated at grain boundaries played a role in preventing the migration of grain boundaries, and the η phase precipitated within grains would form Widmannstatten structure with further increasing solution temperature. η phase precipitated at grain boundaries was dissolved at temperature ranging from 1080 ℃ to 1095 ℃, resulting in grain growth promptly owing to release of the pinning effect on grain boundaries. γ phase precipitated during the process of air cooling after hot rolling and dissolved at temperature ranging between 1010 ℃ and 1020 ℃.

关键词： solution treatment microstructure precipitate AEREX350

Experimental study on jet pulse assembly design and numerical simulation

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Petroleum Science 2020年第1期17卷 222-231页

作者： Liang Xue Hu han dian Wang Xian-Bo Liu He Liu Zhi-Qiang Yu China University of Petroleum–Beijing Beijing 102249China Bohai Drilling Engineering Technology Research Institute Tianjin 300280China

Jet pulse assembly is one of the main components of jet hydraulic *** pressure wave characteristics produced by jet pulse assembly have an important influence on the performance of the *** this paper,the structure and working principle of jet pulse assembly are studied,the mechanical analysis model of piston rod is established,the dynamic resistance ratio formula of jet pulse assembly is deduced,and the numerical simulation test of 89-mm jet pulse assembly structure parameters is carried *** results show that the piston rod downward stroke is driven by both the jet element driving force and the throttle plate load driving force,and can stably *** driving force of the piston rod upward stroke jet element is opposite to the load acting force of the throttle disc,and the jet driving force needs to be greater than the load resistance of the throttle disc to stably *** dynamic resistance ratio formula is *** the area of the end of the piston rod is reduced,the resistance of the throttle disc is reduced and the jet power is increased,thus solving the problem of insufficient power of the piston rod in the upstroke and ensuring the normal operation of the *** groups of numerical simulation tests were carried out,and it was found that the pressure amplitude and pressure drop of the tool decreased significantly with the increase of the tool size,and the error between the numerical simulation value and the theoretical calculation value was less than 9%,which verified the correctness of the *** is suggested to select tools on site according to the drilling construction situation to ensure the drilling effect.

关键词： Friction reduction and torsion Jet pulse assembly Dynamic resistance ratio formula Pressure amplitude Numerical simulation

Multiscale description of molecular packing and electronic processes in small-molecule organic solar cells

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Chinese Chemical Letters 2016年第8期27卷 1453-1463,1471页

作者： Xing-Xing Shen guang-Chao han Yuan-Ping Yi Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

This paper summarizes our recent works on theoretical modelling of molecular packing and electronic processes in small-molecule organic solar ***,we used quantum-chemical calculations to illustrate exciton-dissociation and charge-recombination processes at the DTDCTB/C_（60） interface and particularly emphasized the major role of hot charge-transfer states in the exciton-dissociation ***,we systematically analyzed the influence of DTDCTB surfaces with different features on the vacuum vapor deposition growth and packing morphologies of C_（60） via atomistic molecular dynamics simulations,and found that the formation of crystalline fullerene is the result of an integrated impact of stability,landscape,and molecular orientation of the substrate ***,we investigated the impact of different film-processing conditions,such as solvent evaporation rates and thermal annealing,on molecular packing configurations in a neat small-molecule donor material,DPP（TBFu）_2,and discussed the correlation between charge mobility and molecular packing via atomistic simulations in combination with electronic-structure calculations and kinetic Monte Carlo simulations.

关键词： Molecular packing Molecular self-assembly Photo-induced charge transfer Hot charge transfer state Charge transport Organic photovoltaics