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Reaction behavior of MgO refractory with high-Mn and high-Al steel

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Journal of Iron and Steel Research International 2024年第6期31卷 1389-1398页

作者： Ling-zhong Kong Lin zu Jie Yang Xi-min Zang Xin Yang Ming Kang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina

To understand the mechanism of the interfacial reaction between high-Mn and high-Al steel and MgO refractory,a series of laboratory experiments as well as thermodynamic calculations were *** effects of Mn and Al contents in the steel and the reaction time on the interfacial reaction were *** was observed that the erosion of the MgO refractory is caused by the reaction of Al and Mn in the steel with MgO in the refractory,which would lead to the formation of(Mn,Mg)O·Al_(2)O_(3) spinel and(Mn,Mg)O solid *** formation mechanism of the spinel and solid solution is as *** Al in the steel firstly reacts with MgO in the refractory to generate MgO·Al_(2)O_(3) spinel,and then,the spinel reacts with Mn in the steel to form(Mn,Mg)O·Al_(2)O_(3) ***,the MnO in the spinel reacts with the MgO in the inner refractory to form(Mn,Mg)O solid *** addition,only(Mn,Mg)O·Al_(2)O_(3) spinel is present in the interfacial reaction layer of the refractory when the Al content in the steel is sufficient.

关键词： High-Mn high-Al steel MgO refractory Reaction behavior Spinel

A Review on Flow Boiling of the Fluid with Lower Boiling Point in Micro-Channels

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Journal of Thermal Science 2024年第1期33卷 1-17页

作者： ZHANG Zhiqiang JIA Li DANG chao Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

With the advancement of micro machining technology,the high-heat-flux removal from miniature electronic devices and components has become an attractive *** boiling in micro-channels is an optimal form of heat transfer and has been widely employed in high-heat-flux cooling *** comprehensively-reviewed article focused on the available recent literatures of experimental investigation regarding the flow boiling heat transfer and unstable behaviors of the fluid with lower boiling point in *** thermal-fluid characteristics and potential heat transfer mechanisms of low-boiling-point fluids flow boiling in different narrow passages were summarized and *** literatures regarding the pressure drop and occurrence of the unstable phenomena existing in two-phase flow boiling process were also *** emphasis was given to the heat transfer enhancement methods as well as instability elimination,and various methods such as modification of surface and channel flow geometries were *** future researches in the field of micro-scale flow boiling were suggested.

关键词： flow boiling lower boiling point fluids mini/micro-channels instabilities enhancement suppression

Edge and lithium concentration effects on intercalation kinetics for graphite anodes

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Journal of Energy Chemistry 2024年第3期90卷 337-347,I0009页

作者： Keming Zhu Denis Kramer chao Peng School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048ShanxiChina Faculty of Mechanical Engineering Helmut-Schmidt UniversityHamburg 22043Germany School of Engineering University of SouthamptonSouthampton SO171BJUK Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina

Graphite interfaces are an important part of the anode in lithium-ion batteries(LIBs),significantly influencing Li intercalation *** anodes adopt different stacking sequences depending on the concentration of the intercalated Li *** this work,we performed first-principles calculations to comprehensively address the energetics and dynamics of Li intercalation and Li vacancy diffusion near the no n-basal edges of graphite,namely the armchair and zigzag-edges,at high Li *** find that surface effects persist in stage-Ⅱ that bind Li strongly at the edge ***,the pronounced effect previously identified at the zigzag edge of pristine graphite is reduced in LiC_(12),penetrating only to the subsurface site,and eventually disappearing in LiC_(6).Consequently,the distinctive surface state at the zigzag edge significantly impacts and restrains the charging rate at the initial lithiation of graphite anodes,whilst diminishes with an increasing degree of *** diffusion time for Li hopping to the bulk site from either the zigzag edge or the armchair edge in LiC_(6) was observed during high state of charge due to charge *** controlling Li occupation and diffusion kinetics at this stage is also crucial for enhancing the charge rate.

关键词： Graphite anode Edge Interface Lithium-ion batteries Density functional theory

Synergistic Effects of Carbon Nanotube(CNT)and Reduced Graphene Oxide(RGO)on Mechanical and Thermal Properties of ZK61 Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 577-585页

作者： Fanjing Meng Wenbo du Ning Ding Jian Sun Xian du Ke Liu Shubo Li College of Materials Science and Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion *** with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinforced by RGO+CNT complex exhibited significant enhancements both in mechanical and thermal *** adjusting the proportion of RGO and CNT in ZK61 alloy,the obtained optimum ZK61/(0.06 wt%RGO+0.54 wt%CNT)composite exhibited increase of 25.4%in yield strength,26.5%in ultimate tensile strength,104%in failure strain and 30.4%in thermal conductivity,respectively,in comparison with ZK61 *** superior properties of the nano-hybrid composite are attributed to the synergetic effects of RGO and CNT,leading to a uniform dispersion and integrated structure as well as the enhanced interfacial bonding with *** strengthening ability of RGO and CNT was calculated to quantify their individual contribution to the improvement in mechanical and thermal properties of the ZK61 matrix *** RGO+CNT hybrids provide a promising way to develop Mg matrix composites with impressive performances.

关键词： Mg matrix composite Carbon nanotube Reduced graphene oxide Mechanical performance Thermal conductivity

The lithology and composition of lunar mantle modified by ilmenite bearing cumulate:A thermodynamic model

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Acta Geochimica 2024年第5期43卷 856-875页

作者： Wei Huang Wei du State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Comparative Planetology Chinese Academy of SciencesHefei 230026China

due to their high density,the ilmenite-bearing cumulates(IBC)(with or without KREEP)formed during the late-stage lunar magma ocean solidification are thought to sink into the underlying lunar mantle and trigger lunar mantle *** evidence implied that IBC may descend deep inside the Moon and remain as a partially molten layer at the core-mantle boundary(CMB).However,partial melting may have occurred on the mixed mantle cumulates during the sinking of IBC/KREEP and the silicate melt may be positively buoyant,thus preventing the IBC/KREEP layer from sinking to the ***,we perform thermodynamic simulation on the stability of lunar mantle cumulates at different depths mixed with different amounts of IBC/KREEP from an updated LMO *** modeling results suggest that the sinking of IBC/KREEP will cause at least 5 wt%partial melting in the shallow(~120 km)and a much larger degree of partial melting in the deep lunar mantle(~420 km).due to the density contrast with the surrounding mantle,IBC/KREEP-bearing melts could potentially decouple under certain *** modified lunar mantle by sinking of IBC/KREEP can better explain the formation of different kinds of lunar basaltic magma than the primary lunar mantle formed through differentiation of lunar magma *** of IBC/KREEP back into the lunar mantle may introduce plagioclase,clinopyroxene,garnet,and incompatible radioactive elements into the deep lunar mantle,which will further affect the thermal and chemical evolution of the lunar interior.

关键词： Ilmenite-bearing cumulate KREEP Partial melting Lunar mantle overturn pMELTS

Molecular solid solution of lanthanide-titanium-oxo clusters with enhanced photocatalytic hydrogen evolution

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Science China Chemistry 2024年第2期67卷 529-535页

作者： Rong Chen chao-Long Chen Hui Zhang Zi-Han Wang Fu-Li Sun Ming-Hao du Gui-Lin Zhuang Cheng Wang La-Sheng Long Lan-Sun Zheng Xiang-Jian Kong Collaborative Innovation Centre of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China College of Chemical Engineering Zhejiang University of TechnologyHangzhou310032China

Molecular solid solutions of metal clusters containing different metal centers with well-defined structures can accurately regulate the HOMO-LUMO gap,but are rarely ***,a series of colorless lanthanide-titanium-oxo clusters Ln_(2)Ti_4(μ_(2)-O)_(2)(μ_(3)-O)_4(Piv)_(10)(THF)_(2)(Ln_(2)Ti_4,Ln = Eu,Gd,Tb,and Ce,HPiv = pivalic acid) were synthesized by the reaction of pivalic acid with Ln(Ac)_(3) and titanium *** light yellow crystal of cluster solid solutions Eu_(2)Ti_(4-x)Cd_(x),containing a mixture of Eu_(2)Ti_4 and Eu_(2)Ti_(3)Cd,was obtained by in situ doping Cd^(2+) and S^(2–).Eu_(2)Ti_(3.92)Cd_(0.08) displays efficient photocatalytic hydrogen evolution activity without a co-catalyst,which is up to 2.6 times that of Eu_(2)Ti_*** time-resolved transient absorption spectroscopy and spin-polarized density functional calculations showed that the enhanced photocatalytic performance of Eu_(2)Ti_(4-x)Cd_(x) can be attributed to the narrower HOMO-LUMO gap and lower LUMO position than that of Eu_(2)Ti_*** studyprovides an in situ doping method to realize the simple preparation of cluster solid solution.

关键词： molecular solid solution lanthanide-titanium-oxo clusters photocatalytic hydrogen evolution

A Real-Time Small Target Vehicle Detection Algorithm with an Improved YOLOv5m Network Model

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Computers, Materials & Continua 2024年第1期78卷 303-327页

作者： Yaoyao du Xiangkui Jiang School of Automation Xi’an University of Posts and TelecommunicationsXi’an710121China

To address the challenges of high complexity,poor real-time performance,and low detection rates for small target vehicles in existing vehicle object detection algorithms,this paper proposes a real-time lightweight architecture based on You Only Look Once(YOLO)***,a lightweight upsampling operator called Content-Aware Reassembly of Features(CARAFE)is introduced in the feature fusion layer of the network to maximize the extraction of deep-level features for small target vehicles,reducing the missed detection rate and false detection ***,a new prediction layer for tiny targets is added,and the feature fusion network is redesigned to enhance the detection capability for small ***,this paper applies L1 regularization to train the improved network,followed by pruning and fine-tuning operations to remove redundant channels,reducing computational and parameter complexity and enhancing the detection efficiency of the *** is conducted on the VisDrone2019-DET *** experimental results show that the proposed algorithmreduces parameters and computation by 63.8% and 65.8%,*** average detection accuracy improves by 5.15%,and the detection speed reaches 47 images per second,satisfying real-time *** with existing approaches,including YOLOv5m and classical vehicle detection algorithms,our method achieves higher accuracy and faster speed for real-time detection of small target vehicles in edge computing.

关键词： Vehicle detection YOLOv5m small target channel pruning CARAFE

Functional characterization,structural basis,and protein engineering of a rare flavonoid 2′-O-glycosyltransferase from Scutellaria baicalensis

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Acta Pharmaceutica Sinica B 2024年第8期14卷 3746-3759页

作者： Zilong Wang Xueqing du Guo Ye Haotian Wang Yizhan Liu Chenrui Liu Fudong Li HansÅgren Yang Zhou Junhao Li chao He De-An Guo Min Ye State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesPeking UniversityBeijing 100191China Anhui Key Laboratory of Modern Biomanufacturing and School of Life Sciences Anhui UniversityHefei 230601China National Science Center for Physical Sciences at Microscale Division of Molecular&Cell Biophysics and School of Life Sciences University of Science and Technology of ChinaHefei 230026China Department of Physics and Astronomy Uppsala UniversityUppsala SE-75120Sweden School of Pharmacy Jinan UniversityGuangzhou 510632China Shanghai Research Center for Modernization of Traditional Chinese Medicine Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China

Glycosylation is an important post-modification reaction in plant secondary metabolism,and contributes to structural diversity of bioactive natural *** plants,glycosylation is usually catalyzed by *** 2′-O-glycosides are rare ***,no UGTs have been reported,thus far,to specifically catalyze 2′-O-glycosylation of *** this work,UGT71AP2 was identified from the medicinal plant Scutellaria baicalensis as the first flavonoid 2′-*** could preferentially transfer a glycosyl moiety to 2′-hydroxy of at least nine flavonoids to yield six new *** of the 2′-O-glycosides showed noticeable inhibitory activities against cyclooxygenase *** crystal structure of UGT71AP2(2.15Å)was solved,and mechanisms of its regio-selectivity was interpreted by pKa calculations,molecular docking,MD simulation,MM/GBSA binding free energy,QM/MM,and hydrogen‒deuterium exchange mass spectrometry *** structure-guided rational design,we obtained the L138T/V179D/M180T mutant with remarkably enhanced regio-selectivity(the ratio of 7-O-glycosylation byproducts decreased from 48%to 4%)and catalytic efficiency of 2′-O-glycosylation(kcat/Km,0.23 L/(s·μmol),12-fold higher than the native).Moreover,UGT71AP2 also possesses moderate UDP-dependent de-glycosylation activity,and is a dual function *** work provides an efficient biocatalyst and sets a good example for protein engineering to optimize enzyme catalytic features through rational design.

关键词： Glycosyltransferase Regio-selectivity Crystal structure De-glycosylation Catalytic mechanisms

Application of transient Rayleigh wave in detection of tunnel lining void area

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Global Geology 2024年第1期27卷 56-62页

作者： ZHENG chao WANG Yanlong ZHANG Baohui du Lizhi College of Construction Engineering Jilin UniversityChangchun 130026China China Water Northeastern Investigation Design&Research Co.Ltd.Changchun 130021China Changchun Urban Investment Infrastructure Construction Project Management Consulting Co. LtdChangchun 130031China

Transient Rayleigh wave detection is a high-precision nondestructive detection *** present,it has been widely used in shallow exploration,but rarely used in tunnel lining quality *** the tunnel lining physical model experiment,the layout defects of the double-layer reinforcement lining area were detected and the Rayleigh wave velocity profile and dispersion curve were analyzed after data process-ing,which finally verified the feasibility and accuracy of Rayleigh wave method in detecting the tunnel lining void *** results show that the method is not affected by the reinforcement inside the lining,the shallow detection is less disturbed and the accuracy is higher,and the data will fluctuate slightly with the deepening of the detection *** the same time,this method responds quite accurately to the thickness of the concrete,allowing for the assessment of the tunnel lining’s lack of *** method has high efficiency,good reliability,and simple data processing,and is suitable for nondestructive detection of internal defects of tun-nel lining structure.

关键词： transient Rayleigh wave detection tunnel lining quality detection dispersion curve Rayleigh wave velocity profile