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DMCP燃料机理及其在燃烧数值模拟中应用
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作者 董兆佳 王静波 《化学研究与应用》 CAS 北大核心 2023年第9期2191-2196,共6页
高能量密度燃料具有更高的体积热值,其机理研究对发动机燃烧过程模拟具有重要意义。针对火箭发动机使用的高能量密度燃料1,2-二环丙基-1-甲基环丙烷(DMCP),本文构建了其燃烧反应详细机理,并采用直接关系图法(DRG)以及基于DRG的敏感度分... 高能量密度燃料具有更高的体积热值,其机理研究对发动机燃烧过程模拟具有重要意义。针对火箭发动机使用的高能量密度燃料1,2-二环丙基-1-甲基环丙烷(DMCP),本文构建了其燃烧反应详细机理,并采用直接关系图法(DRG)以及基于DRG的敏感度分析方法(DRGASA),以燃料点火延迟时间为指标进行简化,得到了40物种133反应的简化机理。在当量比0.5-2.0,压力1.0-20.0 atm,温度900-1300 K的宽工况范围内,通过动力学模拟进行了简化机理的验证,点火延迟时间平均误差为12.59%,层流火焰速度平均误差为6.64%,表明简化机理的合理性。将该简化机理用于火箭发动机模型燃烧室的数值模拟,并与总包机理的数值模拟对比,结果表明高精度简化机理模拟的流场合理,而总包机理对温度的预测偏高,表明该简化机理可用于发动机燃烧模拟。 展开更多
关键词 高能量密度燃料 dmcp 反应机理 模型燃烧室 数值模拟
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Dependence of Decamethylcyclopentasiloxane (DMCPS) Dissociation on Ionized Energy by Using Quadrupole Mass Spectrum
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作者 张海燕 叶超 宁兆元 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第6期677-680,共4页
Dependence of decamethylcyclopentasiloxane (DMCPS) organosilicon dissociation on ionized energy in the energy range of 25 eV to 70 eV is investigated by using a quadrupole mass spectrometry. At the ionized energy be... Dependence of decamethylcyclopentasiloxane (DMCPS) organosilicon dissociation on ionized energy in the energy range of 25 eV to 70 eV is investigated by using a quadrupole mass spectrometry. At the ionized energy below 55 eV, the dissociation of DMCPS is dominant. As the ionized energy is above 55 eV, the DMCPS dissociation achieves the maximum cross section, while the fragments from the DMCPS dissociation can further dissociate, which leads to a different ingredient of fragments. At the lower ionized energy of 25 eV, the main fragments are SiOC2H+, SiCH+, Si+, O+ and CH+ ions, which shows an important effect on the SiCOH low-k film deposition. 展开更多
关键词 quadrupole mass spectrum DISSOCIATION ionized energy dmcpS organosilicon
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钨酸钠催化过氧化氢合成4,6-二甲氧基-2-甲磺酰基嘧啶 被引量:6
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作者 占昌朝 彭游 +1 位作者 陶春元 李继红 《中国钨业》 CAS 北大核心 2008年第4期38-41,共4页
以30%(质量分数)的双氧水为氧化剂,钨酸钠与含O的双齿有机配体(草酸)形成的络合物为催化剂,在无有机溶剂、无相转移剂的条件下,研究了4,6-二甲氧基-2-甲巯基嘧啶(d)催化氧化合成4,6-二甲氧基-2-甲磺酰基嘧啶(e)的反应。实验表明,用草酸... 以30%(质量分数)的双氧水为氧化剂,钨酸钠与含O的双齿有机配体(草酸)形成的络合物为催化剂,在无有机溶剂、无相转移剂的条件下,研究了4,6-二甲氧基-2-甲巯基嘧啶(d)催化氧化合成4,6-二甲氧基-2-甲磺酰基嘧啶(e)的反应。实验表明,用草酸为配体,当原料DMCP(d)用量为100mmol时,较佳反应条件为钨酸钠∶草酸∶4,6-二甲氧基-2-甲巯基嘧啶的物质的量比为3.0∶5.0∶100,30%(质量分数)双氧水的体积为35mL,在65~70℃下反应6h,可制得的4,6-二甲氧基-2-甲磺酰基嘧啶。并通过HPLC,IR和1H-NMR对目标产品进行了分析。以4,6-二甲氧基-2-甲巯基嘧啶计,氧化收率>88%,目标产品HPLC纯度大于99%。 展开更多
关键词 4 6-二甲氧基-2-甲磺酰基嘧啶 4 6-二甲氧基-2-甲巯基嘧啶 钨酸钠 催化氧化 合成
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粉喷桩加固软土岸坡抗滑性能现场实验研究
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作者 张芳 王伟 夏天 《水运工程》 北大核心 2008年第3期33-36,共4页
介绍了某软土岸坡粉喷桩加固水平抗滑实验实例。该岸坡分别进行了天然基础、单桩基础和四桩基础的抗滑实验。通过传感器量测了水平荷载施加过程中粉喷桩桩身应力分布及其变化。实验结果表明,水平荷载作用下:天然岸坡经过粉喷桩加固后,... 介绍了某软土岸坡粉喷桩加固水平抗滑实验实例。该岸坡分别进行了天然基础、单桩基础和四桩基础的抗滑实验。通过传感器量测了水平荷载施加过程中粉喷桩桩身应力分布及其变化。实验结果表明,水平荷载作用下:天然岸坡经过粉喷桩加固后,抗滑能力有明显改善;单桩基础和四桩基础的摩擦角、粘聚力对应相差不大,但桩身应力的发挥模式不同;6.0 m以下的水泥土桩桩身应力随水平荷载变化不明显。 展开更多
关键词 软土岸坡 抗滑性能 粉喷桩 现场实验
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A density-functional-theory-based and machine-learning-accelerated hybrid method for intricate system catalysis 被引量:2
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作者 Xuhao Wan Zhaofu Zhang +1 位作者 Wei Yu Yuzheng Guo 《Materials Reports(Energy)》 2021年第3期81-90,共10页
Being progressively applied in the design of highly active catalysts for energy devices,machine learning(ML)technology has shown attractive ability of dramatically reducing the computational cost of the traditional de... Being progressively applied in the design of highly active catalysts for energy devices,machine learning(ML)technology has shown attractive ability of dramatically reducing the computational cost of the traditional density functional theory(DFT)method,showing a particular advantage for the simulation of intricate system catalysis.Starting with a basic description of the whole workflow of the novel DFT-based and ML-accelerated(DFT-ML)scheme,and the common algorithms useable for machine learning,we presented in this paper our work on the development and performance test of a DFT-based ML method for catalysis program(DMCP)to implement the DFT-ML scheme.DMCP is an efficient and user-friendly program with the flexibility to accommodate the needs of performing ML calculations based on the data generated by DFT calculations or from materials database.We also employed an example of transition metal phthalocyanine double-atom catalysts as electrocatalysts for carbon reduction reaction to exhibit the general workflow of the DFT-ML hybrid scheme and our DMCP program. 展开更多
关键词 dmcp program Machine learning Density functional theory DFT-ML hybrid Scheme CATALYSIS Double-atom catalysts
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Intermediate Gas Phase of CH_4/[Si(CH_3)_2O]_5 Plasma and Its Effect on Structure of SiCOH Film
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作者 杜杰 叶超 +1 位作者 宁兆元 张海燕 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第6期731-734,共4页
This paper investigated the radical behaviour of the plasma of a mixture of methane (CH4) and decamethylcyclopentasiloxane (DMCPS) by optical emission spectroscopy. The plasma was generated by electron cyclotron r... This paper investigated the radical behaviour of the plasma of a mixture of methane (CH4) and decamethylcyclopentasiloxane (DMCPS) by optical emission spectroscopy. The plasma was generated by electron cyclotron resonance (ECR) discharge and was used for depositing porous SiCOH low dielectric-constant film. In the ECR discharge plasma, CH, H, H2, C2, Si, O and SiO radicals were obtained. The CH, H and C2 radicals were from the dissociation of CH4, while the SiO. Si and O radicals from the dissociation of the Si-O chain. CHx radicals absorbed in the film were thermally unstable and could be removed by annealing. The dissociation of the Si-O chain led to an increase in a ratio of the Si-Ocage to Si-Onetwork. The removed of CHx radicals and the increased Si-Ocage to Si-Onetwork ratio were beneficial for reducing the film density and dielectric constant. 展开更多
关键词 optical emission spectroscopy CH4/dmcpS ECR plasma SiCOH film
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