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Journal of Thermal Science 2022年第2期31卷 541-551页

作者： jin kairu TIAN Zhenyu Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

In the past 30 years,the effect of thermal radiation and convection heat transfer,which are predominant at high temperature and can affect the measurement accuracy of thermocouple,were not fully considered in the field of laminar flame *** this work,the effect of thermal radiation heat transfer was newly calculated by determining the spectral irradiation heat flux from the whole space to thermocouple and the radiation heat loss from thermocouple junction to *** reveals that the thermocouple itself maintains at high temperature,resulting serious thermal radiation heat loss,which can be compensated via receiving energy from convection-transferred heat as well as thermal radiation emitted by flame and burner *** method was applied to correct the temperatures measured by thermocouple in rich nitromethane flame as *** results indicate that the radiation heat loss plays a dominant role,while the radiations emitted by flame and burner surface account for minor contribution with the percentage of 20.78%at the height above burner(HAB)of 0.4 mm,3.63%at HAB of 2.0 mm and even smaller at higher *** correction states that the maximum temperature error is 117.60 K,where the effect of thermal radiation emitted by flame and burner surface is less than 1.75 ***,it is provably reasonable and feasible to concentrate on the radiation heat loss and ignore the effect of thermal radiation emitted by flame and burner in real combustion processes.

关键词： thermal radiation heat transfer temperature error premixed laminar flame

Experimental and Modeling Study on C_(2)H_(2)Oxidation and Aromatics Formation at 1.2 MPa

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Journal of Thermal Science 2023年第2期32卷 866-880页

作者： TIAN Zhenyu TIAN Dongxu jin kairu CHNE jintao jin Zhihao LI Wang DU Lijun YANG Jiuzhong Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

Oxidation of acetylene(C_(2)H_(2))has been investigated in a high-pressure jet-stirred reactor(HP-JSR)with equivalence ratiosΦ=0.5,1.0,2.0 and 3.0 in the temperature range of 650 K-900 K at 1.2 MPa.18 products and intermediates were analyzed qualitatively and quantitatively by gas chromatography(GC)and gas chromatography-mass spectrometry(GC-MS).Generally,withΦincreasing,the production of intermediates increases ***_(4),C_(2)H_(4),C_(2)H_(6),C_(3)H_(6)and C_(3)H_(8)were important intermediates,which were formed abundantly atΦ=*** light hydrocarbon intermediates could be an important reason for significant formation of cyclopentadiene,benzene,toluene and styrene atΦ=3.0.A detailed kinetic mechanism consisting of 299 species and 2041 reactions has been developed with reasonable predictions against the present data and previous results obtained at 0.1 *** to flux and sensitivity analysis,H and OH radicals play important roles in the consumption of C_(2)H_(2).The combinations among light hydrocarbons and their free radicals are the main generation pathways of aromatics.C_(3)H_(3),IC_(4)H_(5)and AC_(3)H_(5)are important precursors for the formation of *** comparing the results of atmospheric pressure and high pressure,it can be found that increasing the pressure is conducive to fuel consumption and aromatics generation.

关键词： acetylene high pressure oxidation jet-stirred reactor aromatics mechanism flux analysis sensitivity analysis

Oxidation of norbornadiene:Theoretical investigation on H-atom abstraction and related radical decomposition reactions

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Propulsion and Power Research 2023年第1期12卷 104-113页

作者： jintao Chen Mingxia Liu Yuxiang Zhu kairu jin Zhenyu Tian Lijun Yang Chong-Wen Zhou School of Energy and Power Engineering Beihang UniversityBeijing 100191China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Astronautics Beihang UniversityBeijing 100191China Combustion Chemistry Centre School of Biological and Chemical SciencesUniversity of GalwayGalway H91TK33Ireland

The chemical kinetics of hydrogen atom(H-atom)abstraction reactions from norbornadiene(NBD)by five radicals(H,O(^(3)P),OH,CH_(3),and HO_(2)),and the unimolecular reactions of three NBD derived radicals,were studied through high-level ab-initio *** geometries optimization and vibrational frequencies calculation for all the reactants,transition states,and products were obtained at the M06-2X/6-311ttG(d,p)level of *** zeropoint energy(ZPE)corrected potential energy surfaces(PESs)were determined at the QCISD(T)/cc-pVDZ,TZ level of theory with basis set corrections from MP2/cc-pVDZ,TZ,QZ methods for single point energy *** transition state theory(TST)was used for the rate constants calculations of H-atom abstraction reactions by five radicals(H,O(^(3)P),OH,CH_(3),and HO_(2))at temperatures from 298.15 to 2000 K,while the a-site H-atom abstraction reaction rate constant of NBD by OH radical has been obtained through variational transition state theory(VTST).The results show that the H-atom abstraction reactions from the α-carbon atom of NBD are the most critical channels at low *** rate constants for H-atom abstraction reactions by OH radical are also the fastest among all of the reaction channels investigated at the temperature range from 298.15 to 2000 ***-Ramsperger-Kassel-Marcus/Master Equation(RRKM/ME)has been used to calculate the pressure-and temperature-dependent rate constants for the unimolecular reactions of three related C7H7 product radicals which generated from H-atom abstraction reaction within temperature ranges of 300-2000 K and pressures of 0.01-100 atm.A combination of composite methods has been used to calculate the temperature-dependent thermochemical properties of NBD and related *** the calculated kinetics and thermochemistry data can be utilized in the model development for NBD oxidation.

关键词： Norbornadiene Ab-initio calculations Rate constants Kinetic Thermochemistry

水稻黄绿叶调控基因YGL18的克隆与功能解析

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植物学报 2022年第3期57卷 276-287页

作者：杨凯如贾绮玮金佳怡叶涵斐王盛陈芊羽管易安潘晨阳辛德东方媛王跃星饶玉春浙江师范大学化学与生命科学学院金华321004 中国水稻研究所水稻生物学国家重点实验室杭州310006

叶色突变体往往伴随着叶绿素含量变化及叶绿体结构异常,是研究叶绿体发育与光合作用相关基因功能的重要材料。该研究通过甲基磺酸乙酯(EMS)诱变籼稻(***)品种华占(HZ)获得黄绿叶突变体,将其命名为ygl18(yellow-green leaf 18)。与野生... 详细信息

叶色突变体往往伴随着叶绿素含量变化及叶绿体结构异常,是研究叶绿体发育与光合作用相关基因功能的重要材料。该研究通过甲基磺酸乙酯(EMS)诱变籼稻(***)品种华占(HZ)获得黄绿叶突变体,将其命名为ygl18(yellow-green leaf 18)。与野生型相比,黄绿叶突变体ygl18自三叶期起叶片开始变黄且程度不断加深,同时伴随着光合速率与叶绿素含量下降,且结实率、千粒重及有效穗数均显著降低。透射电镜观察结果显示,ygl18的叶绿体结构紊乱,基质片层疏松,发育受到抑制,与叶片出现黄绿色表型一致。遗传分析表明,ygl18突变性状受1对隐性等位核基因控制,这对等位基因位于水稻第3号染色体长臂标记InDel2和InDel3之间115.2 kb范围内。进一步研究发现该突变体表型是编码铁氧还蛋白FdC2的基因LOC_Os03g48040的5’UTR发生突变所致。通过CRISPR转基因实验验证了该基因对表型的控制作用。研究结果揭示了叶色调控网络的遗传基础,可为今后选育高光效水稻品种提供新线索。

关键词：水稻叶色变异遗传分析图位克隆铁氧还蛋白

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百万吨级乙烯装置裂解炉先进控制系统设计与应用

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乙烯工业 2021年第1期33卷 56-61,I0002页

作者：李平许锦胡天生唐登银乔泰蔡宏斌李恺如辽宁科技大学电子与信息工程学院辽宁鞍山114051 恒力石化(大连)化工有限公司辽宁大连116318 沈阳工业大学电气工程学院辽宁沈阳110870

以恒力石化(大连)化工有限公司1500 kt/a乙烯装置裂解炉为例,详细描述裂解炉的工艺流程,分析常规控制方案存在的问题,进而重新设计控制系统,该系统包括平均COT控制、支路温度平衡控制、支路温度“高控”“低控”和总进料流量提/降量控... 详细信息

以恒力石化(大连)化工有限公司1500 kt/a乙烯装置裂解炉为例,详细描述裂解炉的工艺流程,分析常规控制方案存在的问题,进而重新设计控制系统,该系统包括平均COT控制、支路温度平衡控制、支路温度“高控”“低控”和总进料流量提/降量控制。并且还介绍控制系统的工程实施,其中包括先进控制系统硬软件平台、先进控制与常规控制的切换逻辑、先进控制系统操作界面等。本系统的投用提高了裂解炉控制的平稳度,延长了裂解炉的运行周期,带来了显著的经济效益。

关键词：裂解炉先进控制温度控制

多层螺旋CT及气道三维重建在阻塞性睡眠呼吸暂停综合征中的诊断价值

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重庆医学 2015年第32期44卷 4510-4511页

作者：傅江涛金凤桐黄庆琳林黎明叶叔文胡焱钟振波沈川林洪斌徐开睿叶再挺浙江省丽水市人民医院耳鼻咽喉头颈外科 323000 浙江省丽水市人民医院放射科 323000

目的分析应用多层螺旋CT及气道三维重建技术评价阻塞性睡眠呼吸暂停综合征患者咽壁软组织和上气道狭窄情况。方法选取该院92例阻塞性睡眠呼吸暂停综合征患者作为观察组,另取92例健康人作为对照组,对全部患者进行多层螺旋CT及气道三维重... 详细信息

目的分析应用多层螺旋CT及气道三维重建技术评价阻塞性睡眠呼吸暂停综合征患者咽壁软组织和上气道狭窄情况。方法选取该院92例阻塞性睡眠呼吸暂停综合征患者作为观察组,另取92例健康人作为对照组,对全部患者进行多层螺旋CT及气道三维重建技术检查,统计并比较观察组与对照组患者咽壁软组织和上气道狭窄情况。结果观察组患者的舌后区、腭后区及喉咽部的气道与对照组相比明显狭窄(P<0.05);观察组患者的咽壁软组织较厚,软腭的长度和宽度均大于对照组(P<0.05)。结论应用多层螺旋CT及气道三维重建技术可以有效地评估阻塞性睡眠呼吸暂停综合征患者的咽壁软组织和上气道狭窄情况。

关键词：体层摄影术,螺旋计算机气道三维重建技术阻塞性睡眠呼吸暂停综合症咽壁软组织上气道狭窄