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991.
Xuefeng Fan Wenyu Sun Zhongkai Liu Yi Gao Jiuzhong Yang Bin Yang Chung K. Law 《Proceedings of the Combustion Institute》2021,38(1):321-328
Diisopropyl ether (DIPE) is considered as a promising gasoline additive due to the favorable blending Reid vapor pressure and the low water solubility. To get a good understanding of the DIPE oxidation chemistry, oxidation experiments of a stoichiometric mixture of DIPE/O2/Ar/Kr were performed in a jet-stirred reactor (JSR) at atmospheric pressure over the temperature range of 525–900 K in this work. About 30 intermediates and products were identified and quantified using a photoionization molecular-beam mass spectrometer (PI-MBMS). Furthermore, a detailed kinetic model was proposed for DIPE oxidation, which showed satisfactory performances in predicting the species concentration profiles in this work as well as those in literature. For DIPE oxidation, the fuel consumption was observed only above 750 K, even though DIPE has two tertiary hydrogen atoms that are easy to be abstracted so that low-temperature oxidation reactivity is expected. The low oxidation reactivity at low temperature is because the formed OOQOOH radical mostly dissociates back to QOOH+O2, instead of undergoing intramolecular isomerization which leads to the low-temperature chain-branching. At higher temperature, DIPE is mainly consumed by hydrogen abstraction reactions from the carbon atoms adjacent to the oxygen atom, producing dominantly the IC3H7OC(CH3)2 fuel radical, which then decomposes rapidly via CO bond β-scission instead of combining with O2. In contrast, the minor fuel radical IC3H7OCH(CH3)CH2 tends to go through the O2 addition reaction and the subsequent chain branching reactions, as confirmed by the detection of cyclic ether intermediates. Propylene and acetone are the most abundant intermediates in DIPE oxidation, both of which predominantly come from the initial fuel decomposition steps. Other intermediates are mainly formed via the consumption of these two species. 相似文献
992.
该文在M/M/c排队驱动系统中加入工作休假策略,研究了单重工作休假多服务台排队驱动的流体模型.利用拟生灭过程和矩阵几何解法得到驱动系统稳态队长分布.构建净输入率结构,导出流体模型的稳态联合分布函数满足的的矩阵微分方程组,进而利用Laplace-Stieltjes变换(LST)方法得到稳态下缓冲器库存量的空库概率及均值表达式.最后,给出模型在多信道无线Mesh网下的应用,通过数值例子展示参数变化对系统性能指标的影响. 相似文献
993.
李好好 《纯粹数学与应用数学》2021,37(2):243-252
提出并研究了一类非同类机的极小化最大完工时间的保密排序问题Rm||Cmax.该问题的模型参数分为若干组,每个组都由一个不愿意共享或公开自己数据的单位所拥有.基于随机矩阵变换构造了一个不泄露私有数据且与原问题等价的安全规划模型,求解该安全模型可以获得问题的最优解,而且各单位的隐私数据仍然保持不被泄露. 相似文献
994.
Acta Mathematica Sinica, English Series - In this paper, we give some sufficient conditions for extended neighborhood coronas to have Laplacian perfect state transfer. We also give some conditions... 相似文献
995.
Analysis Mathematica - In this paper, we investigate general Lp-mixed brightness integrals which were defined by Yan and Wang. We give their extremal values and establish Brunn-Minkowski type... 相似文献
996.
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998.
Ayub Khurram Shahzad Zaman Waqas Qamar Miran Waheed Ali Meesam Abbas Zain Mushtaq Umair Shahzad Asif Yang Ji 《Research on Chemical Intermediates》2022,48(10):4227-4248
Research on Chemical Intermediates - Volatile organic compounds (VOCs) represent a very important class of pollutants that causes serious health effects. There is an urgent requirement to establish... 相似文献
999.
Juanjuan Zhou Dr. Kai Huang Shaochen Lin Nan Zhang Xin Wang Dr. Yang Li Prof. Zhanjun Li Prof. Gang Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(26):e202104366
While concerns about improving recharged afterglow intensity in vivo still motivate further exploration, afterglow nanoparticles (AGNP) offer unique optical merit for autofluorescence-free biological imaging. Apart from efforts enhancing the afterglow emission properties of AGNP, improving afterglow excitation response to visible or near infrared light is important but has lacked success. Dye sensitization has been used to improve the optical response of photovoltaic nanomaterials and to enhance upconversion luminescence efficiency. This concept has recently been expanded and applied to AGNPs. As a new multifunctional nanoprobe, such dye-sensitized AGNP takes advantage of both high spatial resolution fluorescence imaging and sensitive afterglow imaging. This Concept introduces the background, the concept, mechanism, and related imaging application, as well as reviewing existing challenges and proposing future developmental directions for the dye-sensitized AGNPs. 相似文献
1000.
Hu Qiu-Fen Zhang Ling-Fang Liu Ming-Xin Cai Bing-Biao Li Yong Zhou Tao Li Man-Fei Wang Hua-Shun Xu Yong Kong Wei-Song Zhou Min Yang Guang-Yu Jiang Ju-Xing 《Chemistry of Natural Compounds》2022,58(3):511-515
Chemistry of Natural Compounds - Two new chromeno[3,2-c]pyridin derivatives, 8-acetyl-3-(hydroxymethyl)-7-methoxy-10H-chromeno[3,2-c]pyridin-10-one (1) and... 相似文献