Article
Chemistry, Physical
Clayton R. Mulvihill, Yuri Georgievskii, Stephen J. Klippenstein
Summary: This paper investigates the quantitative descriptions of non-adiabatic transition rates at intermediate temperatures, focusing on the interplay between quantum effects and anharmonicity in the seam potential. The findings highlight the importance of quantum effects and anharmonicity in non-adiabatic reactions at intermediate temperatures.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Geochemistry & Geophysics
Andrew C. Turner, Nicholas J. Pester, Markus Bill, Mark E. Conrad, Kevin G. Knauss
Summary: The hydrogen isotopic composition of methane can serve as an indicator of gas origins. This study presents experimental constraints on the kinetics of hydrogen isotope exchange between methane and supercritical water, showing that exchange rates vary with temperature and suggesting the influence of life activity and thermogenic natural gas systems. The findings have implications for understanding the signatures of methane and water on Earth and other planetary bodies.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Chemistry, Physical
Xudong Mao, Xiaojun Hu, Weiyu Cui, Hiroyuki Matsuura, Fumitaka Tsukihashi, Kuochih Chou
Summary: A novel isotope exchange method is developed for measuring the rate constant of hydrogen production from water and steelmaking slag. The apparent rate constant of the reaction increases with temperature and the probable rate controlling steps of reaction are biased towards interfacial chemical reaction.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Fei Wei, Aslan Kosakian, Jiafei Liu, James Kracher, Rafid Khan, Marc Secanell
Summary: Water balance in anion exchange membrane fuel cells is crucial for improving performance and durability. Accurate measurement of water transport properties is important for AEM design. This study used the liquid-vapor permeation method to determine water flux and analyzed the results using three numerical models. The findings suggest that interfacial transport is the limiting factor.
JOURNAL OF POWER SOURCES
(2023)
Article
Chemistry, Analytical
Guozhan Jiang, Rachel Fenwick, Jonathan Seville, Hameed B. Mahood, Rex B. Thorpe, Suchismita Bhattacharya, D. A. Sanchez Monsalve, Gary A. Leeke
Summary: The measurement of kinetic parameters in the pyrolysis of polyolefins requires the use of a lumped kinetic model. A non-isothermal method was established to predict the product distribution, and the measured parameters were validated using isothermal experimental data. The non-isothermal method proves to be a faster approach for measuring intrinsic rate constants at high temperatures.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2022)
Article
Chemistry, Multidisciplinary
Claudio M. Nunes, Jose P. L. Roque, Srinivas Doddipatla, Samuel A. Wood, Robert J. McMahon, Rui Fausto
Summary: This study presents a new example of chemical reactivity governed by quantum tunneling and highlights the limitations of classical theories. The different conformers of a 2-formylphenylnitrene underwent spontaneous rearrangement to different products, and the kinetics measurements provided evidence of concomitant tunneling reactions.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Physical
Yuri Bedjanian
Summary: The rate constant of the reaction F + CH4 → HF + CH3 was studied in the temperature range 220-960K using a discharge flow reactor combined with mass spectrometry. The kinetic data obtained were compared with previous measurements and theoretical calculations.
CHEMICAL PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Amit Kumar, Pradeep Kumar
Summary: This study investigates the OH + HCl reaction on the surface of ice using Born-Oppenheimer molecular dynamics (BOMD) simulation. The results show that the reaction rate on the ice surface is about 10 times faster than the bare reaction. The simulation also reveals that the Cl radical formed during the reaction can make hydrogen bonds with water molecules on the ice surface, which makes it difficult for the Cl radical to escape.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Multidisciplinary Sciences
Timothee Constantin, Bartosz Gorski, Michael J. Tilby, Saloua Chelli, Fabio Julia, Josep Llaveria, Kevin J. Gillen, Hendrik Zipse, Sami Lakhdar, Daniele Leonori
Summary: This work presents a distinct reactivity mode enabled by quantum mechanical tunneling using a cyclohexadiene derivative as the abstractor under mild photochemical conditions. Experimental and computational studies reveal a noncanonical pathway for activation of various organic compounds.
Article
Chemistry, Multidisciplinary
Pengfei Qian, Shilei Zhang, Fan Luo, Jiarui Wang, Xinyu Zhang, Xuejun Liu, Xiaodong Chen, Wei Wang, Xiaobei Chen
Summary: A co-catalyzed hydrogen-deuterium exchange method has been developed to selectively introduce deuterium at a specific position of enals. The protocol is mild and simple, allowing for high level deuterium incorporation in structurally diverse aromatic-derived enals and dienals.
CHEMICAL COMMUNICATIONS
(2022)
Article
Engineering, Chemical
Xiao-Hui Wang, Xiao-Jie Xu, Jin Cai, Yi-Wei Wu, Yi-Xin Chen, Wei-Xin Pang, Chang-Yu Sun, Guang-Jin Chen
Summary: This work developed a new method to directly measure the intrinsic dissociation rate of gas hydrate and modified the driving force in the dissociation model. The results demonstrate that the new model can accurately describe the effect of temperature on the hydrate decomposition rate.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Environmental
Sarah Suhnholz, Frank-Dieter Kopinke, Katrin Mackenzie
Summary: Several studies have recently been published on sulfate radicals as strong oxidants and methods of their generation. A shift can be observed from homogeneous to heterogeneous methods for persulfate activation as a way to generate sulfate radicals. However, the influence of the surface on the radical chemistry has not been thoroughly examined. In this study, homogeneous persulfate activation methods are compared with heterogeneous activation by FeS. The selectivity patterns for the oxidation of chlorinated ethenes, ethanes, and benzenes differ depending on the persulfate activation method. The data suggests that sulfate radicals generated at the FeS surface have different selectivities than freely dissolved radicals. Furthermore, the kinetic isotope effects for the oxidation of methanol isotopologues with sulfate radicals differ significantly between the homogeneous and heterogeneous systems. This leads to the conclusion that sulfate radicals generated on the FeS surface react as surface-associated radicals with a different selectivity pattern.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Delu Gao, Dunyou Wang
Summary: The study on the F + C2H6 reaction using quantum reaction dynamics reveals that the stretching motion enhances reactivity the most and there is a slight hindrance from the stretching motion between CH2 and CH3. Energy shifting method was used to calculate rate constants and the results show agreement with experimental measurements.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Thermodynamics
Peter Simon, Tibor Dubaj, Zuzana Cibulkova
Summary: This paper reviews the frequent flaws, mistakes, and misconceptions encountered in manuscripts dealing with thermoanalytical kinetics, providing recommendations for their improvement and enhancing the quality of kinetic research.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2022)
Article
Thermodynamics
Shanshan Ruan, Jiuzheng Yin, Ying Shi, Chunlan Qin, Kangwei Xu, Chenliang He, Xixi Hu, Lidong Zhang
Summary: In this study, the low-temperature oxidation mechanism of carbon-neutral fuel diethoxymethane (DEM) was investigated. The reaction potential energy surfaces (PESs) of three different DEM radicals reacting with O2 were explored. The rate constants of the relevant reactions were calculated and the main reaction channels were discussed. The data obtained were incorporated into the DEM combustion model, showing good agreement with experimental data and providing support for further study.
COMBUSTION AND FLAME
(2023)
Article
Materials Science, Multidisciplinary
Jiantao Zhang, Xiaojun Hu, Kuochih Chou
Article
Metallurgy & Metallurgical Engineering
Yuewen Fan, Xiaojun Hu, Rong Zhu, Kuochih Chou
STEEL RESEARCH INTERNATIONAL
(2020)
Article
Materials Science, Multidisciplinary
Jiantao Zhang, Xiaojun Hu, Kuochih Chou
Summary: The addition of Ti can refine grains, improve pitting potential, and lower passive current densities, but an excessive amount can cause phase imbalance and precipitation of coarse particles. The increase in the ratio of Cr2O3 and Mo6+ in the passive film helps to form a stable film.
MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION
(2021)
Article
Geochemistry & Geophysics
Zhanwei He, Xiaojun Hu, Mo Lan, Jianxing Liu, Gongjin Cheng, Xiangxin Xue, Kouchih Chou
Summary: Different types of vanadia-titania magnetite (VTM) have varying reduction and softening-melting-dripping properties in a blast furnace, with an increase in TiO2 content negatively impacting performance. It is recommended to smelt high TiO2 VTM mixed with ordinary ores or with an increased pellet ratio in the burden structure to counteract the adverse effect on softening-melting-dripping properties.
Article
Materials Science, Multidisciplinary
Yuewen Fan, Xiaojun Hu, Rong Zhu, Kuochih Chou
Summary: The application of O2-CO2 mixture injection is an effective method for reducing emissions in steelmaking. Real-time analysis using online mass spectrometry and dual isotope gases provides insights into the non-equilibrium reaction mechanism during the decarburization process.
Article
Metallurgy & Metallurgical Engineering
Zhanwei He, Mo Lan, Xiaojun Hu, Xiangxin Xue, Kuo-Chih Chou
Summary: The formation of MgFe2O4 is closely related to oxidation temperature, oxidation time, and airflow rate. Within a certain range, with the increase in temperature, oxidation time, and airflow rate, the conversion rate and grade of MgFe2O4 can be enhanced, which is significant for improving the recovery efficiency of slag.
STEEL RESEARCH INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Zhanwei He, Xiaojun Hu, Wan Han, Xudong Mao, Kuo-Chih Chou
Summary: The erosion mechanism and kinetics of Al-Li melt on 316L stainless steel were studied through erosion experiments. The microstructure and composition of the Al-Li/316L liquid-solid interface were analyzed, and the phase transformation and structure evolution during the erosion process were investigated. The results provided theoretical guidance for the smelting and casting of Al-Li alloy.
Article
Materials Science, Multidisciplinary
Jiawei Ma, Baicheng Zhang, Yu Fu, Xiaojun Hu, Xinfeng Cao, Zhimin Pan, Ya Wei, Hong Luo, Xiaogang Li
Summary: This study investigated the influence of cold deformation on the microstructure evolution and corrosion behavior of SLMed 316L stainless steel in a simulated cathode environment for PEMFCs. The results showed that the corrosion resistance improved with increasing deformation levels, but decreased at 70% deformation due to decreased stability of the passive film.
Article
Materials Science, Multidisciplinary
Pritesh Garg, Xiaojun Hu, Yuan Li, Kejiang Li, Samik Nag, Jianliang Zhang
Summary: The reduction of iron oxide using hydrogen in different H2/H2O mix gas was studied in this research, showing that the kinetics of the reduction reaction was influenced by the mole fraction of H2O in the mix gas. Higher H2O content in the gas mixture led to a diffusion-controlled reaction process, affecting the activation energy and hindering further reaction at high temperatures.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Mo Lan, Zhanwei He, Xiaojun Hu
Summary: In this study, BOF slag was taken as the research object, and oxidation reconstruction and alcohol wet magnetic separation were carried out to efficiently recover and utilize the slag. The experimental results showed that the iron recovery rate could be increased with appropriate reconstruction temperature and magnetic field intensity, but the iron grade would decrease.
Article
Green & Sustainable Science & Technology
Yuewen Fan, Xiaojun Hu, Yuanhang Zheng, Rong Zhu, Hiroyuki Matsuura, Kuochih Chou
Summary: This study investigates the application of O2-CO2 mixed injection pattern in the steelmaking process and determines the optimal mixing ratio and injection stages through thermodynamic analysis and mass spectrometry monitoring experiment. It aims to save oxygen and improve furnace gas quality.
JOURNAL OF SUSTAINABLE METALLURGY
(2022)
Article
Materials Science, Multidisciplinary
Xinfeng Cao, Xiaojun Hu
Summary: This study analyzes the micro-galvanic corrosion of SAF 2205 duplex stainless steel (DSS) annealed at different temperatures with different phase ratios in a 1M H2SO4 + 1 M NaCl solution. The results of numerical simulation model are consistent with the immersion test results, indicating that the micro-galvanic corrosion depth initially decreases and then increases with the increase in phase ratios. The best micro-galvanic corrosion resistance is obtained at an annealing temperature of 1100 degrees C.
MATERIALS AND CORROSION-WERKSTOFFE UND KORROSION
(2022)
Article
Materials Science, Multidisciplinary
Xinfeng Cao, Xiaojun Hu
Summary: The electrochemical properties of the constitute phases of DSS are studied using single-phase samples prepared by selective dissolution. A numerical simulation model is established in COMSOL Multiphysics software to study the micro-galvanic corrosion of DSS in 1 M H2SO4 + 1 M NaCl solution. Immersion experiments are performed and 3D morphologies of DSS are measured to validate the simulation model. The relationship between galvanic corrosion depth and time is calculated mathematically, which agrees well with the modeling and experiment results.
Article
Materials Science, Multidisciplinary
Xudong Mao, Pritesh Garg, Xiaojun Hu, Yuan Li, Samik Nag, Saurabh Kundu, Jianliang Zhang
Summary: Isothermal reduction of iron ore powder with hydrogen/carbon monoxide gas mixture can be divided into two series of steps. The reduction rate is influenced by hydrogen partial pressure and is higher with pure hydrogen compared to pure carbon monoxide. Hydrogen promotes carbon deposition and increases the apparent activation energy with increasing hydrogen content.
INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS
(2022)
Article
Engineering, Environmental
Zhanwei He, Xiaojun Hu, Kuo-Chih Chou
Summary: With the continuous exploitation of primary high-quality mineral resources, it is important to recover iron-rich BOF slag as secondary mineral resources. This study proposed a method of synergetic modification of copper slag and BOF slag, and investigated the effects of oxidation temperature and addition amount of copper slag on the modification process. The addition of copper slag effectively promoted the transformation of iron oxides to MgFe2O4, and the best results were obtained when the basicity of the mixed slag was 2. Increasing the oxidation temperature was beneficial to the formation and development of MgFe2O4, but excessively high temperature reduced the magnetism of MgFe2O4 and hindered magnetic separation. The modified mixed slag at 1200 degrees C showed potential for sintering or ironmaking.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2022)
