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燃料化学学报 2014年第3期42卷 350-356页

作者： Sameh M.K.Aboul-Fotouh Ain Shams University Faculty of EducationChemistry Department

The catalytic conversion of methanol to dimethylether(dme)was studied over CuO/Al2O3,ZnO/Al2O3and ZnOCuO/Al2O3nanocatalysts prepared in presence or absence of ultrasonic *** catalysts were characterized by X-ray diffraction(XRD),surface characterization method(BET),scanning electron microscope(SEM),H2-temperature programmed reduction(H2-TPR)and temperature programmed desorption of ammonia(NH3-TPD).The experimental results show that during catalytic dehydration of methanol to dimethylether,the activities of the CuO/Al2O3,ZnO/Al2O3and ZnO-CuO/Al2O3catalysts prepared using ultrasonic treatment are much higher than those prepared in absence of *** shows that the use of ultrasonication results in much smaller *** and XRD show that the ultrasonication increases the surface area and pore volume of the catalysts.H2-TPR profiles indicated that reducibility of the sonicated nanocatalysts is carried out at lower ***3-TPD shows that ultrasound irradiation has enhanced the acidity of the nanocatalyst and hence enhanced catalytic performance for dme formation.

关键词： dme 燃料化学氧化铜氧化锌

Laminar Flame Structure-Dependent Exergy Destruction Behavior at Auto-Ignition Time Scale:A Case Study of Dimethyl Ether(dme)

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Journal of Thermal Science 2024年第4期33卷 1257-1271页

作者： WU Honghuan HUANG Wenlin ZHAO Hao SUN Wuchuan HUANG Zuohua ZHANG Yingjia State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China

Hybrid deflagration/auto-ignition flame structures coexist in the combustion of advanced *** exergy destruction caused by different irreversible processes under varied flame regimes is thus important for understanding engine *** this study,the flame propagation modes for the premixed dme/air mixtures are numerically investigated under engine-relevant *** entropy generation and exergy destruction characteristics are compared under different flame *** reveal that as the typical premixed flame transition towards auto-ignition front,the exergy destruction from heat conduction and species mass diffusion gradually vanish and are dominated by chemical *** distributions of temperature and species mole fraction in the flame domain are analyzed to clarify the exergy destruction behaviors caused by heat conduction and mass ***,by dividing the dme oxidation process into four stages,the main reaction channels that contribute to the increase in exergy destruction from chemical reaction have been *** is found that the production and consumption of CH_(2)O and HO_(2) radical dominate the exergy destruction behavior during dme *** this basis,the kinetic mechanism of low-temperature chemistry causing greater exergy destruction is ***,low-temperature chemistry leads to significant exergy destruction due to(a)the large irreversibility of itself and(b)(mainly)the enhancement of H_(2)O_(2)loop reactions by low-temperature reaction *** the reduction of combustion irreversibility is promising to be achieved by reasonably regulating the fuel oxidation path.

关键词： exergy destruction flame structures entropy generation low-temperature chemistry dme

Numerical modeling of dimethyl ether (dme) bubble growth and breakup

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Chinese Science Bulletin 2009年第14期54卷 2457-2463页

作者： ZHANG Peng ZHANG YuSheng Faculty of Energy and Power Engineering Huazhong University of Science and Technology Wuhan 430074 China

A numerical program is written to simulate the process of vapor bubble growth with spherical symmetry from the thermodynamic critical radius in an initially uniformly superheated liquid. The program is validated by the experimental data of superheated water. The calculated results agree with those of experiments well. The program takes into account the variations of properties with temperature precisely to simulate the dme bubble growth under flash boiling conditions. Considering the influences of pressure, surface tension and viscous stress, the linear stability analysis method is adopted to deduce the dispersion equation to represent the disturbance development during the bubble growth, and a new criterion for bubble breakup is established. The results show the bubble becomes more unstable with the increase of bubble Weber number and void fraction, and that with the increase of bubble growth rate or the decrease of initial radius ration of droplet to bubble, the breakup time of bubble becomes shorter.

关键词：数值模拟汽泡生长二甲基醚 dme 分裂定性分析方法过热液体临界半径

Progress and Prospect of Single-step Synthesis of dme

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China Petroleum Processing & Petrochemical Technology 2010年第2期12卷 1-7页

作者： Guo Xiangbo Research Institute of Petroleum Processing SINOPEC Beijing 100083

Patents and previous research concerning the single-step synthesis of dme were reviewed. Rapid deactivation of the bifunctional catalyst is the main issue for the commercialization of the single-step synthesis process; in addition, the separation process and utilization of by-products have a larger impact on economic performance of the process. Recent progress involving the development of bifunctional catalysts and separation technology in the single-step process will most likely make the process commercially available in the near future.

关键词： single step dme synthesis

dme/O2/N2预混冷焰的着火与熄火研究

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工程热物理学报 2019年第7期40卷 1668-1673页

作者：张扬杨协和沈文锋张海王双峰清华大学能源与动力工程系热科学与动力工程教育部重点实验室北京100084 中国科学院力学研究所微重力国家重点实验室北京100190

本文通过数值模拟研究了dme/O2/N2预混冷焰的着火和熄火特性,并与其热焰的性质进行了对比。研究使用了全混流反应器(PSR)和对冲火焰两个模型。PSR研究结果表明与热焰相比冷焰着火和熄火对当量比的变化并不敏感。通过对冲预混冷焰的计算... 详细信息

本文通过数值模拟研究了dme/O2/N2预混冷焰的着火和熄火特性,并与其热焰的性质进行了对比。研究使用了全混流反应器(PSR)和对冲火焰两个模型。PSR研究结果表明与热焰相比冷焰着火和熄火对当量比的变化并不敏感。通过对冲预混冷焰的计算发现冷焰燃烧的温度为700~760 K,在当量比为0.6~1.4范围内,冷焰熄灭拉伸率和熄灭极限火焰温度都随着当量比单调增加,冷焰熄灭拉伸率变化率仅为-20%,远小于热焰熄灭拉伸率的变化率。

关键词： dme 预混冷焰着火熄火

INDO　Studies　on　the　Electronic　Structure　of(2,4-C₇H₁₁)₂Yb（dme）

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Chemical Research in Chinese Universities 1998年第1期14卷 59-64页

ＩＮＤＯＳｔｕｄｉｅｓｏｎｔｈｅＥｌｅｃｔｒｏｎｉｃｓＳｔｒｕｃｔｕｒｅｏｆ（２，４－Ｃ７Ｈ１１）２Ｙｂ（ＤＭＥ）ＦＥＮＧＪｉａｎ－ｎａｎ，ＷＡＮＧＺｈｉ－ｚｈｏｎｇ，ＺＨＡＮＧＳｏ－ｂｏ，ＬＩＵＪｕ－ｚｈｅｎｇ（Ｉ... 详细信息

ＩＮＤＯＳｔｕｄｉｅｓｏｎｔｈｅＥｌｅｃｔｒｏｎｉｃｓＳｔｒｕｃｔｕｒｅｏｆ（２，４－Ｃ７Ｈ１１）２Ｙｂ（ＤＭＥ）ＦＥＮＧＪｉａｎ－ｎａｎ，ＷＡＮＧＺｈｉ－ｚｈｏｎｇ，ＺＨＡＮＧＳｏ－ｂｏ，ＬＩＵＪｕ－ｚｈｅｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＴｈｅｏｒｅｔ...

关键词： INDO Studies Electronic the Structure dme C7H Yb

SYNTHESIS AND CRYSTAL STRUCTURE OF {C(η~5-C_5H_5)_4Nd_4(μ_4-O) (μ_2-Cl)_8)]·[Li(dme)_2THF]_2

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Chinese Journal of Structural Chemistry 1991年第1期10卷 60-66页

作者：李详高刘静芝等 ChangchunInstituteofAppliedChemistry AcademiaSinic ChangchunInstituteofAppliedCh

The reaction of （η5-C5H5）3Nd·THF and NdCl3·2LiCl·nTHF in solution at room temperature gave rise to[（η5-C5H5）4Nd4（μ4-O）(μ2-Cl)8][Li（dme）2THF]2 （Mr = 1654.44）. Crystals of the compound were obtained at about - 10℃. The intensity data were collected under nitrogen atmosphere at-60℃. The crystal belongs to the rhombic system with space group Pna21 and the unit cell parameters : a=19. 010（7）,b = 23. 231（6） ,c= 14. 180（4） A ;V = 6261. 91 （A3） , DC= 1. 67 （g/cm3）, λ（MoKa） = 0. 71069A,F（000） = 3240,μ（mm-1） = 3. 660;Z = 4. Least-squares refinement with anisotropic temperature factors for all non-hydrogen atoms led to the final R=0. 054, Rw = 0. 056. The molecule is made up of the anion group and the cation. The oxygen atom links four Nd3+together as μ4-bridge. The eight chlorine atoms form the eight chlorine-bridge bonds among four Nd3+ions. The average bond length is : Nd-O=2. 374,Nd-Cl = 2. 811,Nd-C=2. 777,Nd（a）- Nd（b） = 3. *** bond angles of Nd（a） -Nd （b）-Nd（c） fall in the range of 623°,th

关键词： Nd dme SYNTHESIS AND CRYSTAL STRUCTURE OF C5H5 Li THF Cl

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dme发动机着火与燃烧过程的数值模拟研究

华中科技大学学报（自然科学版） 2002年第7期30卷 23-26页

作者：陆艺红张煜盛刘镇华中科技大学能源与动力工程学院海军工程大学动力工程学院

从含氧清洁燃料二甲醚 (dme)低温着火的化学反应机理入手 ,开展了dme自燃着火过程的数值模拟研究 ,进而建立了不同温度、压力和燃空当量比条件下dme着火滞燃期的数据库 ,通过将该数据库与发动机工作过程的模拟模型相耦合 ,对dme发动机... 详细信息

从含氧清洁燃料二甲醚 (dme)低温着火的化学反应机理入手 ,开展了dme自燃着火过程的数值模拟研究 ,进而建立了不同温度、压力和燃空当量比条件下dme着火滞燃期的数据库 ,通过将该数据库与发动机工作过程的模拟模型相耦合 ,对dme发动机的运转性能进行了变参数预测分析。

关键词： dme 发动机燃烧过程数值模拟柴油机二甲醚燃烧数学模型自然着火过程含氧清洁燃料

dme、dme/R125与润滑油互溶性实验研究

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工程热物理学报 2012年第11期33卷 1836-1838页

作者：毕胜山韦俊刘志刚吴江涛西安交通大学热流科学与工程教育部重点实验室能源与动力工程学院陕西西安710049

利用新搭建的测量制冷剂/润滑油混合物互溶性的实验系统,实验测量了dme/矿物油、dme/酯类油和三种配比的混合制冷剂dme/R125与矿物油的临界互溶温度。结果表明:dme作为制冷剂与各类润滑油都具有良好的互溶性;dme/R125与矿物油的互溶性,... 详细信息

利用新搭建的测量制冷剂/润滑油混合物互溶性的实验系统,实验测量了dme/矿物油、dme/酯类油和三种配比的混合制冷剂dme/R125与矿物油的临界互溶温度。结果表明:dme作为制冷剂与各类润滑油都具有良好的互溶性;dme/R125与矿物油的互溶性,随混合制冷剂中dme比例的增加,临界互溶温度降低。

关键词： dme dme/R125 互溶性

含CO_2、dme和CH_3OH等物质体系的汽液相平衡模型及相图

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工程热物理学报 2004年第6期25卷 901-904页

作者：王宁郑丹星北京化工大学化学工程学院 100信箱北京100029

针对二甲醚生产过程中的汽液相平衡问题,本文提出了适于描述含CO2、dme和CH3OH体系的NRTL-PR模型组合,并以此模型计算了大量关于CO2-dme-CH3OH体系的三元VLE数据,绘制出几组等温、等压三元相图。可以认为,此模型得到的数据和相图能准确... 详细信息

针对二甲醚生产过程中的汽液相平衡问题,本文提出了适于描述含CO2、dme和CH3OH体系的NRTL-PR模型组合,并以此模型计算了大量关于CO2-dme-CH3OH体系的三元VLE数据,绘制出几组等温、等压三元相图。可以认为,此模型得到的数据和相图能准确地反映含二甲醚体系的VLE关系,是实际生产工艺的研究与开发的重要基础。

关键词：清洁燃料 dme 二甲醚 NRTL-PR模型组合相图