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Beyond catalytic materials:Controlling local gas/liquid environment in the catalyst layer for CO_(2)electrolysis

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Journal of Energy Chemistry 2022年第3期31卷 45-51,I0003页

作者： Zhuo xing Kaige Shi Xun hu Xiaofeng Feng School of Material Science and Engineering University of JinanJinan 250022ShandongChina Department of Physics University of Central FloridaOrlandoFL 32816United States Renewable Energy and Chemical Transformations(REACT)Cluster University of Central FloridaOrlandoFL 32816United States

Electrochemical reduction of CO_(2)to value-added chemicals using renewable electricity provides a promising strategy to achieve sustainable fuel production and carbon *** with the development of electrocatalysts,fow cells with gas-diffusion electrodes(GDEs)have been used to reach commercially viable current densities for CO_(2)electrolysis,while the local environment and CO_(2)mass transport in the electrodes remain to be *** this review article,we highlight some insights into the microenvironment in the catalyst layer for CO_(2)electrolysis,including typical mass transport models for CO_(2)reduction in H-type cells and GDE fow cells,the effect of a hydrophobic microenvironment on CO_(2)mass transport and catalytic performance,and the formation of a gas/liquid balance and solid–liquid–gas interfaces for CO_(2)*** insights and discussions in this article can provide important guidelines on the design of catalysts,electrodes,and electrolyzers for CO_(2)electrolysis,as well as other gas-involving electrocatalytic reactions.

关键词： Electrocatalysis CO_(2)reduction Gas-diffusion electrode Microenvironment Activity

Effect of Grain Size on the Precipitation Behaviour in Super-Ferritic Stainless Steels During a Long-Term Ageing

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Acta Metallurgica Sinica(English Letters) 2021年第9期34卷 1285-1295页

作者： hui-hu Lu xing-Quan Shen Wei Liang School of Mechanical Engineering North University of ChinaTaiyuan 030051China College of Materials Science and Engineering Taiyuan University of Technology3 Xueyuan RoadTaiyuan 030024China

A 27.6Cr-3.6Mo-2Ni alloy was solution treated and then aged for a long time to study the effect of grain size on precipitation behaviour by using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The experimental results demonstrated that the average grain size increased from 46.3 ± 6.2 to 101.8 ± 13.5 μm and the grain boundary length per unit area decreased from 3.3 × 10^(4) to 1.7 × 10^(4) m/m^(2) with an increasing annealing temperature from 1100 to 1200 ℃. After ageing at 800 ℃, the σ-phase,χ-phase and Laves phase were observed. As the ageing time increased, the σ-phase notably increased, while the χ-phase and Laves phase gradually decreased before finally vanishing after ageing for 400 h. The σ-phase precipitation kinetics curves consisted of two parts, and the grain size had a significant effect on the first stage of the precipitation curves due to the abundance of nucleation sites in the specimens with finer grains. The Laves phase was transformed from Nb(C,N) particles by Nb diffusion. As the ageing time increased, the ferrite phase decreased due to the transformation of the ferrite phase to the σ-phase, and then C was expelled into the untransformed ferrite grains. Moreover, new Nb(C,N) particles were formed by Nb diffusion from the Laves phase, resulting in the absence of the Laves phase.

关键词： Ferritic stainless steel Grain size Ageing treatment σ-phase precipitation kinetics Laves phase transformation

Modelling the dead fuel moisture content in a grassland of Ergun City,China

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Journal of Arid Land 2023年第6期15卷 710-723页

作者： chang chang chang Yu GUO Meng hu Yuanman CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China School of Geographical Sciences Northeast Normal UniversityChangchun 130024China E'erguna Wetland Ecosystem National Research Station Hulunbuir 022250China

The dead fuel moisture content(DFMC)is the key driver leading to fire *** estimating the DFMC could help identify locations facing fire risks,prioritise areas for fire monitoring,and facilitate timely deployment of fire-suppression *** this study,the DFMC and environmental variables,including air temperature,relative humidity,wind speed,solar radiation,rainfall,atmospheric pressure,soil temperature,and soil humidity,were simultaneously measured in a grassland of Ergun City,Inner Mongolia Autonomous Region of China in *** chose three regression models,i.e.,random forest(RF)model,extreme gradient boosting(XGB)model,and boosted regression tree(BRT)model,to model the seasonal DFMC according to the data *** ensure accuracy,we added time-lag variables of 3 d to the *** results showed that the RF model had the best fitting effect with an R2value of 0.847 and a prediction accuracy with a mean absolute error score of 4.764%among the three *** accuracies of the models in spring and autumn were higher than those in the other two *** addition,different seasons had different key influencing factors,and the degree of influence of these factors on the DFMC changed with time ***,time-lag variables within 44 h clearly improved the fitting effect and prediction accuracy,indicating that environmental conditions within approximately 48 h greatly influence the *** study highlights the importance of considering 48 h time-lagged variables when predicting the DFMC of grassland fuels and mapping grassland fire risks based on the DFMC to help locate high-priority areas for grassland fire monitoring and prevention.

关键词： dead fuel moisture content(DFMC) random forest(RF)model extreme gradient boosting(XGB)model boosted regression tree(BRT)model grassland Ergun City

High-performance position-sensitive detector based on the lateral photoelectrical effect of two-dimensional materials

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Light(Science & Applications) 2020年第1期9卷 1170-1178页

作者： chang hu Xianjie Wang Bo Song Department of Physics Harbin Institute of Technology150001 HarbinChina National Key Laboratory of Science and Technology on Advanced Composites in Special Environments Harbin Institute of Technology150001 HarbinChina

Two-dimensional(2D)materials such as graphene and transition-metal chalcogenides have been extensively studied because of their superior electronic and optical ***,2D materials have shown great practical application in position-sensitive detectors(PSDs),originating from the lateral photoelectrical effect of the materials or *** high position sensitivity and ultrafast photoresponse of PSDs based on 2D materials,especially compatibility with Si technology,may enable diverse optoelectronic *** this review,recent studies of PSDs based on 2D materials are summarized,providing a promising route for high-performance PSDs.

关键词： optoelectronic performance effect

Near-perfect replication on amorphous alloys through active force modulation based on machine learning/neural network parameter prediction

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 181-191页

作者： Senkuan Meng Zheng Wang Ruisong Zhu Ruijie Liu Jiang Ma Lina hu Weihua Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) School of Materials Science and Engineering Shandong University College of Mechatronics and Control Engineering Shenzhen University Songshan Lake Materials Laboratory Institute of Physics Chinese Academy of Sciences

As a microforming technique, micro/nano-structural replication possesses advantages of high precision and efficiency. With the remarkable superplasticity in the supercooled liquid region, amorphous alloys or metallic glasses(MGs) are regarded as ideal materials for miniature fabrication. However, due to the intrinsic metastable nature of supercooled liquids, the design of imprinting processes for MGs poses a challenge. In the past, process parameters have largely relied on trial-and-error *** this work, a low-frequency active force modulation system is employed to apply a stable, precise, and real-time feedback stress field for imprinting of MG samples. Low-frequency vibrations can facilitate the filling of microstructures on the template surface by reducing the effective viscosity of the supercooled liquid. With the dataset composed of orthogonal experiments, a machine learning strategy based on back-propagation(BP) neural networks was utilized to construct a 3D parameter space for temperature, stress, and time, and to predict the corresponding filling ratio. Furthermore, the optimal combination of imprinting process parameters was identified, and its filling ratio was experimentally validated to reach as high as 0.94. The near-perfect replication of microstructures confirms the superiority of the active force modulation system and the data-driven strategy of machine learning-assisted parameter design. At the same time, this one-step microforming process provides a new approach to addressing the accuracy-cost trade-off dilemma in precision manufacturing.

关键词： metallic glass amorphous alloy microforming imprinting machine learning

Mapping out the reaction network of humin formation at the initial stage of fructose dehydration in water

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Green Energy & Environment 2024年第6期9卷 1016-1026页

作者： xing Fu Yexin hu Ping hu hui Li Shuguang Xu Liangfang Zhu changwei hu Key Laboratory of Green Chemistry and Technology Ministry of EducationCollege of ChemistrySichuan UniversityChengduSichuan610064China State Key Laboratory of Southwestern Chinese Medicine Resources Innovative Institute of Chinese Medicine and PharmacyChengdu University of Traditional Chinese MedicineChengduSichuan611137China

The formation of humins hampers the large-scale production of 5-hydroxymethylfurfural(HMF)in ***,a detailed reaction network of humin formation at the initial stage of fructose-to-HMF dehydration in water is delineated by combined experimental,spectroscopic,and theoretical *** bimolecular reaction pathways to build up soluble humins are *** is,the intermolecular etherification of β-furanose at room temperature initiates the C12 path,whereas the C-C cleavage of a-furanose at 130-150℃ leads to C11 path,and that of open-chain fructose at 180℃ to C11' *** successive intramolecular dehydrations and condensations of the as-formed bimolecular intermediates lead to three types of soluble *** show that the C12 path could be restrained by using HCl or AlCl_(3) catalyst,and both the C12 and C110 paths could be effectively inhibited by adding THF as a co-solvent or accelerating heating rate via microwave heating.

关键词： Carbohydrates 5-hydroxymethylfurfural Reaction network Soluble humins Tautomer

Gorenstein FP∞-Injective Modules and w-Noetherian Ring

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Algebra Colloquium 2022年第4期29卷 687-712页

作者： Shiqi xing Xiaoqiang Luo Kui hu College of Applied Mathematics Chengdu University of Information Technology Chengdu 610225China Departments of Mathematics Sichuan University of Arts and Science DazhouSichuan 635000China College of Science Southwest University of Science and Technology MianyangSichuan 621010China

We study some homological properties of Gorenstein FP∞-injective modules,and we prove(1)a ring R is not necessarily coherent if every Gorenstein FP∞-injective R-module is injective,and(2)a ring R is not necessarily coherent if every Gorenstein injective R-module is *** addition,we characterize w-Noetherian rings in terms of Gorenstein FP∞-injective modules,and we prove that a ring R is w-Noetherian if and only if every GV-torsion-free FP∞-injective R-module is Gorenstein FP∞-injective,if and only if any direct sum of GV-torsion-free FP∞-injective R-modules is Gorenstein FP∞-injective.

关键词： Gorenstein FP∞-injective module Gorenstein FP∞-dimension FP-module w-Noetherian ring

Risk-based Optimal Investment and Proportional Reinsurance of an Insurer with Hidden Regime Switching

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Acta Mathematicae Applicatae Sinica 2016年第3期32卷 755-770页

作者： xing-chun PENG Yi-jun hu School of Science Wuhan University of Technology School of Mathematics and Statistics Wuhan University

In this paper, we study the optimal investment and proportional reinsurance strategy for an insurer in a hidden Markov regime-switching environment. A risk-based approach is considered, where the insurer aims at selecting an optimal strategy with a view to minimizing the risk described by a convex risk measure of its terminal wealth. We solve the problem in two steps. First, we employ the filtering theory to turn the optimization problem with partial observations into one with complete observations. Second, by using BSDEs with jumps, we solve the problem with complete observations.

关键词： investment reinsurance hidden Markov chain convex risk measure backward stochastic differential equation

Alkylamine-mediated synthesis and photocatalytic properties of ZnO

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Frontiers of Materials Science 2019年第1期13卷 33-42页

作者： Cuicui hu huanhuan ZHANG Yanjun xing Key Laboratory of Science and Technology of Eco-Textiles(Ministry of Education) College of ChemistryChemical Engineering and BiotechnologyDonghua UniversityShanghai 201620China Shanghai Institute of Quality Inspection and Technical Research Shanghai 200233China

A simple approach to synthesize ZnO microstructures was reported using dodecylamine,hexadecylamine and oleylamine as template *** synthesized ZnO was characterized by XRD,FESEM,TEM,EDS mapping,FTIR,UV-vis DRS,Raman spectroscopy and BET *** oriented ZnO microstructures were *** photocatalytic performance of ZnO prepared with different types of alkylamines was evaluated by the degradation of methylene blue(MB)and methyl orange(MO).The results suggested that alkylamine control the nucleation,growth and morphology of *** photocatalytic properties of ZnO on the degradation of MB and MO decreased with increasing the alkyl chain length in alkylamine.

关键词： ZnO controlled preparation alkylamine photocatalytic property