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Pressure Drop in Cyclone Separator at High Pressure

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Journal of Thermal Science 2008年第3期17卷 275-280页

作者： Zhu Zhiping Na Yongjie Lu qinggang Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100190 Graduate University of Chinese Academy of Sciences Beijing 100190

For the design of pressurized circulating fluidized beds, experiments were conducted in a small cyclone with 120 mm in diameter and 300 mm in height at high pressures and at atmospheric temperatures. Influence of air leakage from the stand pipe into the cyclone was specially focused. A semi-empirical model was developed for the prediction of the pressure drop of the cyclone separator at different operate pressures with the effect of air leakage and inlet solid loading. The operate pressure, air leakage and inlet solid loading act as significant roles in cyclone pressure drop. The pressure drop increases with the increasing of pressure and decreases with the increasing of the flow rate of air leakage from the standpipe and with the increasing of the inlet solid loading.

关键词： cyclone separator pressure drop air leakage

Flow behavior and processing map for hot deformation of ATI425 titanium alloy

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Journal of Materials Science & Technology 2018年第4期34卷 679-688页

作者： qinggang Meng Chunguang Bai Dongsheng Xu Institute of Metal Research Chinese Academy of Sciences

Flow behavior and processing map play important roles in the hot deformation process of titanium alloys. In this research, compression Gleeble tests have been carried out to investigate the stress-strain relationship at temperatures ranging from 700 to 1000 ℃ and strain rates ranging from 0.001 to 1 s-1 for ATI 425 titanium alloy. Arrhenius type constitutive equation was obtained to describe the compressive flow behavior with modification of additional deformation dead zone, friction model, temperature model and strain rate. The introduction of novel calculation method for α value in Arrhenius equation gives more accurate fitting than traditional one. Processing maps were drawn based on the distribution of dissipator co-content, and optimized deformation temperature and strain rate range obtained. It is proven to be accurate and effective through the experimental results. The microstructure analysis shows that more dynamic recrystallization can be achieved in the area with larger ηvalue on the processing map.

关键词： Titanium alloy Flow stress Constitutive equation Processing map

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道路施工中生态环境保护措施优化策略分析

中国厨卫 2024年第8期23卷 243-245页

作者：陈勇升胡庆港浙江建设技师学院经济管理系杭州310022

道路施工过程会对生态环境产生一系列不良影响,因此需要采取相应措施,来保护生态环境。在道路施工过程中,现有的生态环境保护措施虽然在一定程度上能够缓解负面影响,但仍存在效果不足和实施困难等问题。基于此,文章提出了一系列优化策略... 详细信息

道路施工过程会对生态环境产生一系列不良影响,因此需要采取相应措施,来保护生态环境。在道路施工过程中,现有的生态环境保护措施虽然在一定程度上能够缓解负面影响,但仍存在效果不足和实施困难等问题。基于此,文章提出了一系列优化策略,包括技术创新、政策调整及公众参与机制的强化,以期提高道路施工项目的环境保护效果,为相关政策制定和环境管理实践提供参考。

关键词：道路施工生态环境保护措施优化策略环境影响评估

Numerical Simulation on Pulverized Coal Combustion and NO_x Emissions in High Temperature Air from Circulating Fluidized Bed

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Journal of Thermal Science 2013年第3期22卷 261-268页

作者： Jianguo Zhu Ziqu Ouyang qinggang Lu Institute of Engineering Thermophysics Chinese Academy of Sciences

High temperature air combustion is a prospecting technology in energy saving and pollutants reduction. Numerical simulation on pulverized coal combustion and NOx emissions in high temperature air from circulating fluidized bed was presented. The down-fired combustor, taken as the calculation domain, has the diameter of 220 mm and the height of 3000 mm. 2 cases with air staging combustion are simulated. Compared the simulation results with experimental data, there is a good agreement. It is found that the combustion model and NOx formation model are applicable to simulate the pulverized coal combustion and NOx emissions in high temperature air from circulating fluidized bed. The results show that there is a uniform temperature profile along the axis of the down-fired combustor. The NOx emissions are lower than those of ordinary pulverized coal combustion, and the NOx emissions are 390 mg/m3 and 352 mg/m3 in Case 1 and Case 2, respectively. At the range of 300-600 mm below the nozzle, the NO concentration decreases, mainly resulting from some homogeneous reactions and heterogeneous reaction. NO concentration has a little increase at the position of 800 mm below the nozzle as the tertiary air supplied to the combustor at the position of 600 mm below the nozzle.

关键词： Pulverized coal combustion Numerical simulation High temperature air NOx

Agglomeration Characteristics of River Sand and Wheat Stalk Ash Mixture at High Temperatures

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Journal of Thermal Science 2013年第1期22卷 64-70页

作者： Shang Linlin Li Shiyuan Lu qinggang College of Mechanical and Transportation Engineering China University of Petroleum(Beijing Campus) Institute of Engineering Thermophysics Chinese Academy of Sciences

The agglomeration characteristics of river sand and wheat stalk ash mixture at various temperatures are investi- gated using a muffle furnace. The surface structural changes, as well as the elemental makeup of the surface and cross-section of the agglomerates, are analyzed by polarized light microscopy, scanning electron microscopy （SEM）, and energy dispersive X-ray （EDX）. Multi-phase equilibrium calculation is performed with FactSage in identifying the melting behavior of the river sand-wheat stalk ash mixture at high temperatures. No indication of agglomeration is detected below 850~C. At a temperature of 900-1000~C, however, obvious agglomeration is observed and the agglomerates solidify further as temperature increases. The presence of potassium and calcium enrichment causes the formation of a sticky sand surface that induces agglomeration. The main component of the agglomerate surface is KEO-42aO-SiO2, which melts at low temperatures. The formation of molten silicates causes particle cohesion. The main ingredient of the binding phase in the cross-section is K20-SiO2-Na20- Al2Oa--CaO; the agglomeration is not the result of the melting behavior of wheat stalk ash itself but the compre- hensive results of chemical reaction and the melting behavior at high temperatures. The multi-phase equilibrium calculations agree well with the experimental results.

关键词： Wheat stalk ash River sand Agglomeration Phase equilibria Microstructure

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一种无机复合聚苯板的制备与燃烧性能研究

消防科学与技术 2024年第3期43卷 412-418页

作者：王鹏宇司广旭梁庆刚周亮北京建筑材料检验研究院股份有限公司北京100041 北京雅达润邦建筑材料有限公司北京100176 北京科技大学土木与资源工程学院/大安全科学研究院北京100083

采用具有负热值特性的半水硫酸钙等无机材料为主要添加剂制备阻燃浆液,以低密度膨胀聚苯乙烯泡沫为基体,使用负压顺孔与负压吸附技术,制备了无机复合聚苯板;使用导热系数测试仪测试了该复合材料的保温性能,使用氧指数测试仪、热值测试... 详细信息

采用具有负热值特性的半水硫酸钙等无机材料为主要添加剂制备阻燃浆液,以低密度膨胀聚苯乙烯泡沫为基体,使用负压顺孔与负压吸附技术,制备了无机复合聚苯板;使用导热系数测试仪测试了该复合材料的保温性能,使用氧指数测试仪、热值测试仪、锥形量热仪、单体燃烧装置测试其燃烧性能。经检测,该无机复合聚苯板的导热系数为0.041 W/(m^(2).K),热值仅为2.91 MJ/kg,氧指数达到39.7%;锥形量热仪测试结果显示,该复合聚苯板在燃烧过程中未发生收缩熔融,且保持一定的形状,其热释放速率峰值、总热释放量、产烟速率峰值以及总产烟量相比聚苯乙烯泡沫基材大幅降低;单体燃烧测试结果显示,该无机复合聚苯板的燃烧性能等级达到A2级,产烟特性等级达到S1级;分析其阻燃机理,认为主要源于二水硫酸钙吸热的分解反应和惰性的分解产物。

关键词：无机复合聚苯板锥形量热仪单体燃烧装置燃烧性能阻燃机理

基于临界慢化理论的中医“未病”状态识别建模研究初探

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北京中医药大学学报 2024年第3期47卷 312-319页

作者：王诗尧石康乐雷聪杨方燕孟庆刚北京中医药大学北京100029 中国科学院大学黑龙江中医药大学

中医“未病”理论关注从健康到疾病动态、连续的演化特点,重视从健康到疾病复杂、渐变演化过程中的早期辨识和干预。从系统整体性、演化性角度来看,“未病”理论和复杂性科学具有相同本质的健康观和疾病观——将机体视为连续、动态变化... 详细信息

中医“未病”理论关注从健康到疾病动态、连续的演化特点,重视从健康到疾病复杂、渐变演化过程中的早期辨识和干预。从系统整体性、演化性角度来看,“未病”理论和复杂性科学具有相同本质的健康观和疾病观——将机体视为连续、动态变化的复杂系统,呈现“稳态-失稳态-相变-另一稳态”的非线性特点。本文从复杂性科学非线性动力学视角,运用临界慢化理论阐释中医未病-已病演化规律的科学内涵,并基于该理论及其发展产生的动态网络生物标志物方法,结合中医四诊合参的宏观体征及包含转录组学和微生物组学的微观特征,提出融合宏观、微观多层级信息,构建具有中医诊疗特点的“未病”临界状态识别模型,为复杂疾病早期预警提供新视角和新方法。

关键词：未病中医临界慢化复杂系统模型框架动态网络生物标志物

Effect of Pressure on Minimum Fluidization Velocity

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Journal of Thermal Science 2007年第3期16卷 264-269页

作者： Zhu Zhiping Na Yongjie Lu qinggang Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing 100080 Graduate School of the Chinese Academy of Science Beijing 100080

Minimum fluidization velocity of quartz sand and glass bead under different pressures of 0.5, 1.0, 1.5 and 2.0 MPa were investigated. The minimum fluidization velocity decreases with the increasing of pressure. The influence of pressure to the minimum fluidization velocities is stronger for larger particles than for smaller ones. Based on the test results and Ergun equation, an experience equation of minimum fluidization velocity is proposed and the calculation results are comparable to other researchers＇ results.

关键词： minimum fluidization velocity pressure Ergun equation

伴有PAX9突变非综合征型先天缺牙患者的牙颌面表型研究

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上海交通大学学报（医学版） 2024年第6期44卷 687-693页

作者：窦嘉琪高洁卞晓玲王凤代庆刚吴轶群上海交通大学医学院附属第九人民医院口腔第二门诊部上海交通大学口腔医学院国家口腔医学中心国家口腔疾病临床医学研究中心上海市口腔医学重点实验室上海市口腔医学研究所上海201999

目的·评估配对盒基因9(paired box gene 9,PAX9)突变非综合征型先天缺牙(non-syndromic tooth agenesis,NSTA)患者的牙颌面表型。方法·对2016年1月—2023年12月于上海交通大学医学院附属第九人民医院口腔第二门诊部就诊的NSTA患者进... 详细信息

目的·评估配对盒基因9(paired box gene 9,PAX9)突变非综合征型先天缺牙(non-syndromic tooth agenesis,NSTA)患者的牙颌面表型。方法·对2016年1月—2023年12月于上海交通大学医学院附属第九人民医院口腔第二门诊部就诊的NSTA患者进行全外显子组测序,筛查PAX9突变患者。对筛查到的患者采用曲面体层摄影片评估缺牙的位置和数目,采用X射线头影测量评估患者的牙颌面畸形情况。结果·7例PAX9突变的NSTA患者纳入研究,男性3例(42.9%),女性4例(57.1%)。患者首诊年龄7~31岁,平均(19.7±8.0)岁。7例患者均携带PAX9杂合突变,其中4例为错义突变,3例为移码突变。平均缺失恒牙(15.9±2.9)颗,上颌缺失数[(9.6±2.6)颗]略多于下颌[(6.3±2.4)颗](P=0.030)。上颌第二磨牙(100.0%)、上颌尖牙(85.7%)、下颌第二前磨牙(85.7%)为最常见的缺失位点,下颌侧切牙(14.3%)、下颌尖牙(14.3%)为最少缺失的位点。移码突变的患者缺牙数[(18.3±2.1)颗]多于错义突变[(14.0±1.8)颗](P=0.032)。X射线头影测量结果显示:PAX9突变成年患者上牙槽座角(angle sella-nasion-subspinale,SNA)、颌凸角(angle nasion-subspinale-subspinale-porion,NA-APo)和前颅底长度(sella-nasion,S-N)均明显小于正常参考范围,提示上颌后缩,前颅底矢状向发育不足;面角(frankfort horizontal plane-nasion-porion,FH-NPo)大于参考值、Y轴角(Y axis)小于参考值,提示下颌前伸;上/下牙槽座角(angle subspinale-nasion-supramental,ANB)小于参考值,提示骨性Ⅲ类错畸形;上中切牙角(angle upper central incisor-nasion-subspinale,angle U1-NA)大于参考值,提示上中切牙唇倾;下中切牙-下颌平面角(angle lower central incisor-mandibular plane,IMPA)、下中切牙凸度(lower central incisor-nasion-supramental,L1-NB)小于参考值,提示下中切牙舌倾,上下前牙反倾向。结论·较为全面地报道了PAX9突变NSTA患者的牙颌面表型,有利于进一步理解PAX9在人类颌面部发育中的作用。

关键词：配对盒基因9 牙颌面畸形 X射线头影测量非综合征型先天缺牙骨性Ⅲ类错畸形