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101.
杨哲  闫瑾  梁德东  成巍  李卉  李乙 《化学教育》2022,43(14):131-133
研究生课程思政的建设影响着研究生的培养质量,关乎着能否实现立德树人这一人才培养的根本任务。介绍了吉林大学化学学院立足学科特点,在研究生课程思政建设方面取得成功的经验,并对未来的课程思政建设方向进行了探讨。  相似文献   
102.
Jin  Sen  Wang  Hui  Li  Lei  Luo  Xiao  Sun  Xianshun  Zuo  Ming  Tian  Jie  Zhang  Xiaodong  Xie  Yi 《中国科学:化学(英文版)》2021,64(11):1964-1969
Science China Chemistry - Extracting photogenerated species from bulk to surface is an essential process for gaining efficient semiconductor-based photocatalysis. However, compared with charged...  相似文献   
103.
Wei  Runzhe  Lu  Yi  Xu  Yang 《中国科学:化学(英文版)》2021,64(11):1826-1853
Science China Chemistry - Rechargeable ion batteries are one of the most reliable energy storage technologies for the applications ranging from small portable devices and electric vehicles to...  相似文献   
104.
This work investigates the oxidation of hydrogen near its second explosion limit in a turbulent flow reactor at pressures of 1 to 8 bar, temperatures of 950 K and an equivalence ratio of 0.035. The concentrations of H2, O2 and H2O are measured along the reactor and simulated using several kinetic models from the literature. These experiments demonstrate evident negative pressure dependence from roughly 1 to 4 bar, with further increases in pressure resuming its positive impact on reaction rates. The simulated and measured species concentrations along the reactor generally agree within a factor of 2.Further investigation is then conducted to measure the rate coefficient of reaction H + O2 (+ M) = HO2 (+M) (R2), which is one of the most sensitive reactions in hydrogen's oxidation chemistry at these conditions. This investigation is conducted by using nitric oxide (NO) as a dopant and measuring the resulting, quasi-steady-state concentrations of NO2. The rate coefficients are obtained at 950 – 1010 K. Combined with literature results, an Arrhenius expression is proposed, k2,0N2 = 4.50 × 1020 (T/K)?1.73 [cm6 mole?2 s?1], for the reaction rate at the low-pressure limit over 500 K – 2000 K with N2 as the bath gas. Simulations using the models from the literature with the proposed Arrhenius expression for this reaction then demonstrate improved agreement with the experiments.  相似文献   
105.
We investigated the influence of an inserted bar on the hopper flow experimentally.Three geometrical parameters,size of upper outlet D1,size of lower outlet D0,and the height of bar H,are variables here.With varying H we found three regimes:one transition from clogging to a surface flow and another transition from a surface flow to a dense flow.For the dense flow,the flow rate follows Beverloo’s law and there is a saturation of inclination of free surfaceθ.We plotted the velocity field and there is a uniform linear relation between the particle velocity and depth from the free surface.We also found that the required value of D1 to guarantee the connectivity of flow is little smaller than D0.For the transition from a surface flow to a dense flow,there is a jump of flow rate and the minimumθfor flowing is two degrees larger than the repose angle.  相似文献   
106.
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   
107.
Li  Yi Peng  Liu  Xiao Gang  Zhang  Sheng Gui 《数学学报(英文版)》2021,37(12):1921-1932
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   
108.
Yu  Shimo  Zhao  Xinfu  Zhang  Jing  Liu  Sijia  Yuan  Zhipeng  Liu  Xiaochan  Liu  Benxue  Yi  Xibin 《Cellulose (London, England)》2022,29(12):6783-6796
Cellulose - High CO2 concentration in atmosphere causes serious environmental issues, and carbon capture and storage technologies have attracted attention as a means to reduce the atmospheric CO2...  相似文献   
109.
Han  Peng-Fei  Zhang  Yi 《Nonlinear dynamics》2022,109(2):1019-1032
Nonlinear Dynamics - Active researches on the water waves have been done, and water waves are essentially complex waves controlled by gravity field and surface tension. Using the Hirota bilinear...  相似文献   
110.
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