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Co-aromatization of methane and hexane over Pt encapsulated in ZSM-5 zeolite and the electronic effect of K promoters

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Science China Chemistry 2024年第3期67卷 1017-1027页

作者： Bei liu fan Wang Xiaomeng Dou pengfei Li Hongwei xiang Yong Yang peng He State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Department of Chemistry Tsinghua UniversityBeijing 100084China National Energy R&D Center for Coal to Liquid Fuels Synfuels China Technology Co.Ltd.Beijing 101407China University of Chinese Academy of Sciences Beijing 101408China Leibniz-Institut für Katalyse e.V.an der Universitat Rostock Rostock 18059Germany

The co-aromatization of methane with higher hydrocarbons represents a promising route to valorize methane, an abundant but underexploited carbon resource. In this study, we elucidate a novel approach to enhance the catalytic co-aromatization of hexane and methane by confining Pt within zeolite catalysts and modulating its electron density. Our findings show that encapsulating Pt within MFI structure is pivotal for activating the feedstock and fostering the formation of aromatic products. Interaction between K atoms and the silanol nest forms siloxy groups which are critical for the stabilization of Pt species. Tuning the K content in PtSn@MFI catalysts adeptly alters the electronic configuration of Pt clusters. This modification is corroborated by infrared and X-ray photoelectron spectroscopy analysis, and density functional theory calculations. Remarkably, the catalyst with 0.8 wt% K exhibits an optimal Pt electron density, driving its superior efficacy in the co-aromatization reaction, converting 0.78 mol of methane for each mole of hexane processed. By employing ~(13)C isotopic labeling and solid-state NMR studies, we demonstrate the participation of methane in the adsorbed species inside the zeolite channel and its incorporation to the benzyl site of the substitute group and phenyl rings in aromatic compounds, underscoring the importance of Pt encapsulation.

关键词： Pt encapsulation MFI zeolite methane activation co-aromatization ^(13)C solid-state NMR

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Coupling of RANS and BEM Solvers for Simulation of Propeller Behind the Hull in Full Appended Model

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China Ocean Engineering 2024年第3期38卷 424-438页

作者： Saeed NAJAFI Mehdi POURMOSTAFA liu peng-fei Iranian National Institute for Oceanography and Atmospheric Science(INIOAS) Tehran 14155-4781Iran Department of Maritime Engineering Amir Kabir University of TechnologyTehran 15875-4413Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

To design a propeller for ship power plant,the interaction between ship hull and propeller must be taken into *** main concern is to apply the wake effect of ship stern on the propeller *** this paper,a coupled BEM(Boundary Element Method)/RANS(Renolds-Averaged Navier−Stokes)solver is used to simulate propeller behind the hull in the self-propulsion *** motivation of this work is to develop a practical tool to design marine propulsion system without suffering long computational *** unsteady boundary element method which is also known as panel method is chosen to estimate the propeller *** wakes are treated using a time marching wake alignment ***,a RANS code coupled with VoF equation is developed to consider the ship motions and wake field effects in the problem.A coupling algorithm is developed to interchange ship wake field to the potential flow solver and propeller thrust to the RANS *** on the difference between hull resistance and the propeller thrust,a PI controller is developed to compute the propeller RPM in every time *** of the solver is carried out using the towing tank test report of a 50 m oceanography research *** factor and trust deduction coefficient are estimated ***,the wake rollup pattern of the propeller in open water is compared with the propeller in real wake field.

关键词： RANS BEM coupled method ship propeller self-propulsion wake sheet pattern

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Fourth-order phase-field modeling for brittle fracture in piezoelectric materials

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 837-856页

作者： Yu TAN fan peng Chang liu Daiming peng xiangyu LI State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Science Chang'an UniversityXi'an 710064China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and Aerospace EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Failure analyses of piezoelectric structures and devices are of engineering and scientific *** this paper,a fourth-order phase-field fracture model for piezoelectric solids is developed based on the Hamilton *** typical electric boundary conditions are involved in the present model to characterize the fracture behaviors in various physical situations.A staggered algorithm is used to simulate the crack *** polynomial splines over hierarchical T-meshes(PHT-splines)are adopted as the basis function,which owns the *** numerical simulations are performed to study the influence of the electric boundary conditions and the applied electric field on the fracture behaviors of piezoelectric *** electric boundary conditions may influence crack paths and fracture loads *** present research may be helpful for the reliability evaluation of the piezoelectric structure in the future applications.

关键词： isogeometric analysis(IGA) brittle fracture fourth-order phase-field model piezoelectric solid

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Yolk free egg substitute improves the serum phospholipid profile of mice with metabolic syndrome based on lipidomic analysis

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Food Science and Human Wellness 2024年第1期13卷 482-493页

作者： Zhihui Yu Lingyu fan fei tai Lixin Zhang Xiaoyu Zhang Yisheng Chen College of Food Science and Engineering Shanxi Agricultural UniversityTaigu 030801China Insitute of Food Nutrition and Safety Shanxi Agricultural UniversityTaiyuan 030031China Shanxi Key Laboratory of Edible Fungi for Loess Plateau Taigu 030801China

In this study,the impacts of egg consumption on mice model of metabolic syndrome(Met S)were comparatively *** were divided into five groups(n=8):normal diet group(ND),high-fat diet group(HFD),HFD with whole egg group(WE),HFD with free-yolk egg substitute group(YFES),and HFD with lovastatin group(Lov).Main biochemical indexes and a non-targeted lipidomic analysis were employed to insight the lipid profile changes in *** was revealed that WE could significantly improve serum biochemical indexes by reducing body weight,low-density lipoprotein cholesterol(LDL-C)and total cholesterol(TC),while increasing high-density lipoprotein *** exhibited remarkably better performance in increasing phosphatidylglycerol and phosphatidic acids,while decreasing phosphatidylinositol than WE.A total of 50 differential lipids biomarkers tightly related to glycerophospholipids metabolism were screened *** C18:2 and C12:1,SM(d18:0/12:0),and SM(d18:1/14:1)were significantly upregulated in YFES compared to *** reduced expression of SREBP-1c and Cpt1a,while did not affect the expression of PPAR-α.Sphingomyelin biomarkers were positively related to the TC(|r|>0.6),while PPAR-αwas negatively correlated with triglyceride and LDL-C *** sum up,YFES attenuated HFD-induced Met S by improving the serum phospholipids,which account for its modulation of glycerophospholipid metabolism.

关键词： Metabolic syndrome Whole egg Yolk free egg substitute Serum Lipidomics

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Characterization and identification towards dynamic-based electrical modeling of lithium-ion batteries

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Journal of Energy Chemistry 2024年第5期92卷 738-758页

作者： Chuanxin fan Kailong liu Yaxing Ren Qiao peng School of Automation Nanjing Institute of TechnologyNanjing 211167JiangsuChina School of Control Science and Engineering Shandong UniversityJinan 250100ShandongChina School of Engineering University of LincolnLincoln LN67TSUK Information Technology Analytics&Operations GroupQueen’s University BelfastBelfast BT95EEUK

Lithium-ion batteries are widely recognized as a crucial enabling technology for the advancement of electric vehicles and energy storage systems in the *** design of battery state estimation and control algorithms in battery management systems is usually based on battery models,which interpret crucial battery dynamics through the utilization of mathematical ***,the investigation of battery dynamics with the purpose of battery system identification has garnered considerable attention in the realm of battery *** methods in terms of linear and nonlinear response of lithium-ion batteries have emerged as a prominent area of study in this *** review has undertaken an analysis and discussion of characterization methods,with a particular focus on the motivation of battery system ***,this work encompasses the incorporation of frequency domain nonlinear characterization methods and dynamics-based battery electrical *** aim of this study is to establish a connection between the characterization and identification of battery systems for researchers and engineers specialized in the field of batteries,with the intention of promoting the advancement of efficient battery technology for real-world applications.

关键词： Lithium-ion battery Battery dynamics Nonlinear characterization Nonlinear battery model

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Dynamic properties of micro-NPR material and its controlling effect on surrounding rock mass with impact disturbances

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Underground Space 2024年第2期15卷 331-352页

作者： Manchao He Jie Hu tai Cheng fei Deng Zhigang Tao Hongru Li Di peng Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining&TechnologyBeijing 100083China Luohe Vocational Technology College Henan 462002China

A novel meta steel with negative Poisson’s ratio effect(termed as micro-NPR steel)is developed for rock support in deep underground *** possesses high strength,high ductility,and high energy absorption *** this paper,static tension and modified dynamic drop hammer tests are performed on this novel material to investigate its mechanical properties *** based on this material,a new generation of micro-NPR anchor cable is developed and applied in field tests subjected to blasting dynamic *** results of laboratory tests reveal that the ultimate elongation of micro-NPR steel under dynamic impacts is more than 30%and it is over 1.5 times that of Q235;the plastic and total energy absorption of micro-NPR are both significantly higher than that of *** test indicates the fine controlling effect of micro-NPR anchor cable on surrounding rock mass under dynamic *** force confirms that micro-NPR cables can distribute and absorb the dynamic energy uniformly around the supported rock when subjected to dynamic disturbance,avoiding local failure induced by excessive stress *** excavation compensation principle and energy-absorbing characteristics are used to explain the support ***,micro-NPR material and anchor cable can control and prevent dynamic disasters in deep underground engineering effectively.

关键词： Micro-NPR steel Energy-absorbing Drop hammer test Anchor cable Field test

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Rapid lithium-ion insertion/extraction and migration behavior of Na_(2)WO_(4)-encapsulated lithium-rich layered oxide cathode

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Rare Metals 2024年第8期43卷 3647-3660页

作者： Yu-Shen Zhao fan-fan Wang Jian-Cang Wang peng-fei Wang Ting-Feng Yi Jun-Hong Zhang School of Materials Science and Engineering Northeastern UniversityShenyangShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology College of Chemistry and Chemical EngineeringLiaocheng UniversityLiaocheng 252059China

Due to the low cost,high working voltage and high storage capacity,Li-rich Mn-based layered compounds show promise as the cathode materials for lithiumion batteries(LIBs).However,the side reactions at the solid-liquid interface of the cathode will lead to rapid capacity decay and inferior rate ***,this article proposes a liquid-phase dispersion strategy to introduce a Na_(2)WO_(4)layer on the Li_(1.2)Ni_(0.13)-Co_(0.13)Mn_(0.54)O_(2) cathode,which can reduce the side effects between raw materials and electrolyte and promote the insertion/extraction rate of Li^(+),thus enhancing the material stability and rate *** a result,the capacity retention rate is 96.9%after 200 cycles under ***,the capacities are 177.5,149.5,111.1 and58.3 mAh·g^(-1)at 1C,2C,5C and 10C,implying a superior fast charging *** exceptional performance can be ascribed to both the increased conductivity and enhanced structural stability of the cathode ***'s more,based on the investigation of ion insertion/extraction behavior in electrode materials and the ion migration kinetics in the electrolyte,this study suggests that coating Li-rich Mn-based materials with Na_(2)WO_(4)can be a promising strategy to improve their performance in LIBs.

关键词： Li-ion battery Coating Rate performance Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2) Reaction kinetics

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Regional 3D geological modeling along metro lines based on stacking ensemble model

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Underground Space 2024年第5期18卷 65-82页

作者： Xia Bian Zhuyi fan Jiaxing liu Xiaozhao Li peng Zhao Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Yunlong Lake Laboratory of Deep Underground Science and Engineering Xuzhou 221000China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221000China

This paper presents a regional 3D geological modeling method based on the stacking ensemble technique to overcome the challenges of sparse borehole data in large-scale linear underground *** proposed method transforms the 3D geological modeling problem into a stratigraphic property classification problem within a subsurface space grid cell *** data is pre-processed and trained using stacking method with five different machine learning *** resulting modelled regional cells are then classified,forming a regional 3D grid geological model.A case study for an area of 324 km2 along Xuzhou metro lines is presented to demonstrate the effectiveness of the proposed *** study shows an overall prediction accuracy of 85.4%.However,the accuracy for key stratigraphy layers influencing the construction risk,such as karst carve strata,is only 4.3%due to the limited borehole *** address this issue,an oversampling technique based on the synthetic minority oversampling technique(SMOTE)algorithm is *** technique effectively increases the number of sparse stratigraphic samples and significantly improves the prediction accuracy for karst caves to 65.4%.Additionally,this study analyzes the impact of sampling distance on model *** is found that a lower sampling interval results in higher prediction accuracy,but also increases computational resources and time ***,in this study,an optimal sampling distance of 1 m is chosen to balance prediction accuracy and computation ***,the number of geological strata is found to have a negative effect on prediction *** mitigate this,it is recommended to merge less significant stratigraphy layers,reducing computation *** key strata layers,such as karst caves,which have a significant impact on construction risk,further onsite sampling or oversampling using the SMOTE technique is recommended.

关键词： 3D geological modeling Borehole data Stacking Machine learning

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Geophysical prediction of organic matter abundance in source rocks based on geochemical analysis:A case study of southwestern Bozhong Sag,Bohai Sea,China

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Petroleum Science 2024年第1期21卷 31-53页

作者： xiang Wang Guang-Di liu Xiao-Lin Wang Jin-Feng Ma Zhen-Liang Wang fei-Long Wang Ze-Zhang Song Chang-Yu fan State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Continental Dynamics Northwest UniversityXi'an710069ShaanxiChina Department of Geology Northwest UniversityXi'an710069ShaanxiChina CNOOC Tianjin Branch Company Tianjin300459China

The Bozhong Sag is the largest petroliferous sag in the Bohai Bay Basin,and the source rocks of Paleogene Dongying and Shahejie Formations were buried *** of the drillings were located at the structural high,and there were few wells that met good quality source rocks,so it is difficult to evaluate the source rocks in the study area precisely by geochemical analysis *** on the Rock-Eval pyrolysis,total organic carbon(TOC)testing,the organic matter(OM)abundance of Paleogene source rocks in the southwestern Bozhong Sag were evaluated,including the lower of second member of Dongying Formation(E_(3)d2L),the third member of Dongying Formation(E_(3)d_(3)),the first and second members of Shahejie Formation(E_(2)s_(1+2)),the third member of Shahejie Formation(E_(2)s_(3)).The results indicate that the E_(2)s_(1+2)and E_(2)s_(3)have better hydrocarbon generative potentials with the highest OM abundance,the E_(3)d_(3)are of the second good quality,and the E_(3)d2L have poor to fair hydrocarbon generative ***,the well logs were applied to predict TOC and residual hydrocarbon generation potential(S_(2))based on the sedimentary facies classification,usingΔlogR,generalizedΔlogR,logging multiple linear regression and BP neural network *** various methods were compared,and the BP neural network method have relatively better prediction *** on the pre-stack simultaneous inversion(P-wave impedance,P-wave velocity and density inversion results)and the post-stack seismic attributes,the three-dimensional(3D)seismic prediction of TOC and S_(2)was carried *** results show that the seismic near well prediction results of TOC and S_(2)based on seismic multi-attributes analysis correspond well with the results of well logging methods,and the plane prediction results are identical with the sedimentary facies map in the study *** TOC and S_(2)values of E_(2)s_(1+2)and E_(2)s_(3)are higher than those in E_(3)d_(3)and E_(3)d_(2)L,basicall

关键词： Total organic carbon(TOC) Residual hydrocarbon generation potential(S_(2)) Geophysical prediction Seismic attribute Bozhong Sag Bohai Bay Basin

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Peracetic acid catalytic activation using Co3O4 nanocluster decorated graphitic carbon nitride for cefapirin degradation in water

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Science China Technological Sciences 2024年第10期67卷 3103-3115页

作者： YIN ShiMei GAO YiXuan CHEN Long LI fan liu XiaoNa QI fei liu Wen Beijing Key Lab for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry University Key Laboratory of Water and Sediment Sciences (Ministry of Education) College of Environmental Sciences and EngineeringPeking University School of Environmental Science and Engineering Taiyuan University of Technology State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems Peking University Beijing National Laboratory for Molecular Sciences Peking University

This study innovated cobalt-based catalytic nanocomposites（CCNs） for the heterogeneous activation of peracetic acid（PAA）,a green and efficient advanced oxidation process for removing antibiotics from *** Co3O4catalysts exhibit limited activity due to stable electronic *** overcome this,CCNs were synthesized using a one-step condensation method,incorporating a size control strategy that anchors Co3O4nanoclusters within 4-5 nm onto six-fold cavity of g-C3N4,simultaneously modifying the coordination environment of *** alteration significantly enhances the adsorption energy of PAA and catalytic activity compared to commercial *** improved performance of CCN2,in particular,is attributed to a shift in the cobalt d band center towards the Fermi level,facilitating electron delocalization and transfer,enhancing Co-O bonding,and accelerating PAA ***2's superior activity,with a cefapirin（CFP） degradation kinetic rate constant(k1=0.760 min-1)～11 times that of PAA direct oxidation(k1=0.070 min-1) and～5 times that of commercial Co3O4/PAA system(k1=0.164 min-1),is due to its ability to generate dominant reactive species for antibiotic degradation,including alkoxy radicals(CH3C（=O）OO·),high valence metal(CoⅣ（=O）2+),and singlet oxygen（1O2）,with the latter two being crucial for the degradation *** degradation of CFP involved three mechanisms,including direct oxidation by PAA,decarboxylation,and open-ring reactions at nitrogen *** research provides insights into developing high-activity catalysts for efficient PAA activation and antibiotic removal,leveraging the strategy of shifting the transition metal d band center.

关键词： peracetic acid Co3O4 nanocluster high valence metal singlet oxygen cefapirin

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