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Modelling the viscoplastic behaviour of Callovo-Oxfordian claystone with consideration of damage effect

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Journal of rock Mechanics and Geotechnical Engineering 2024年第1期16卷 303-316页

作者： Hao Wang Yu-Jun Cui Minh Ngoc Vu Jean Talandier Ecole des Ponts ParisTech Laboratoire Navier/CERMES6 et 8 avenue Blaise PascalMarne La Vallée cedex 277455France Andra R&D DepartmentChâtenay-Malabry92290France

In order to evaluate the performance of deep geological disposal of radioactive waste,an underground research laboratory(UrL)was constructed by Andra in the Callovo-Oxfordian(COx)claystone formation at the Meuse/Haute-Marne(MHM).The construction of UrL induced the excavation damage of host formations,and the ventilation in the galleries desaturated the host formation close to the gallery ***,it is expected that the mechanical behaviour of COx claystone is *** study presents a constitutive model developed to describe the viscoplastic behaviour of unsaturated and damaged COx *** this model,the unsaturation effect is considered by adopting the Bishop effective stress and the van Genuchten(VG)water retention *** terms of the viscoplastic behaviour,the nonstationary flow surface(NSFS)theory for unsaturated soils is used with consideration of the coupled effects of strain rate and suction on the yield stress.A progressive hardening law is ***,a non-associated flow rule is used,which is similar to that in Barcelona basic model(BBM).In addition,to describe the damage effect induced by suction change and viscoplastic loading,a damage function is defined based on the crack volume *** damage function contains two variables:unsaturated effective stress and viscoplastic volumetric strain,with the related parameters determined based on the mercury intrusion porosimetry(MIP)*** the model validation,different tests on COx claystone under different loading paths are *** between experimental and simulated results indicated that the present model is able to well describe the viscoplastic behaviour of damaged COx claystone,including swelling/shrinkage,triaxial extension and compression,and triaxial creep.

关键词： Callovo-Oxfordian(COx)claystone Excavation damage Time-dependent behaviour Suction Viscoplastic model

A Calculation Method of double Strength reduction for Layered Slope Based on the reduction of Water Content Intensity

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工程与科学中的计算机建模(英文) 2024年第1期138卷 221-243页

作者： Feng Shen Yang Zhao Bingyi Li Kai Wu School of Civil Engineering Suzhou University of Science and TechnologySuzhou215011China r&d department Suzhou Jcon Greenbuild Fabricated Co.Ltd.Suzhou215004China

The calculation of the factor of safety(FOS)is an important means of slope *** paper proposed an improved double strength reductionmethod(drM)to analyze the safety of layered *** physical properties of different soil layers of the slopes are different,so the single coefficient strength reduction method(SrM)is not enough to reflect the actual critical state of the *** that the water content of the soil in the natural state is the main factor for the strength of the soil,the attenuation law of shear strength of clayey soil changing with water content is *** paper also establishes the functional relationship between different reduction ***,a USdFLd subroutine is programmed using the secondary development function of finite element *** the relationship between field variables and calculation time realizes double strength reduction applicable to the layered ***,by comparing the calculation results of different examples,it is proved that the stress and displacement distribution of the critical slope state obtained by the improved method is more realistic,and the calculated safety factor is more *** newly proposedmethod considers the difference of intensity attenuation between different soil layers under natural conditions and avoids the disadvantage of the strength reduction method with uniform parameters,which provides a new idea and method for stability analysis of layered and complex slopes.

关键词： double strength reduction slopes stability water content factor of safety numerical methods

Improving lipid production by rhodotorula glutinis for renewable fuel production based on machine learning

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 23-35页

作者： Lihe Zhang Changwei Zhang Xi Zhao Changliu He Xu Zhang National Energy r&d Center for Biorefinery Beijing University of Chemical TechnologyBeijing 100029China Collage of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Bioprocess Beijing University of Chemical TechnologyBeijing 10029China

Microbial lipid fermentation encompasses intricate complex cell growth processes and heavily relies on expert experience for optimal *** modeling of the fermentation process assists researchers in making intelligent decisions,employing logical reasoning and strategic planning to optimize lipid *** this study,the effects of medium components and concen-trations on lipid fermentation were investigated,*** then,leveraging the collated data,a variety of machine learning algorithms were used to model and optimize the lipid fermentation *** models,based on artificial neural networks and support vector machines,achieved r?values all higher than 0.93,ensuring accurate predictions of the fermentation *** linear regression was used to evaluate the respective target parameter,which were affected by the medium components of lipid ***,single and multi-objective optimiza-tion were conducted for lipid fermentation using the genetic *** results demonstrated the maximum biomass of 50.3 g·L^(-1) and maximum lipid concentration of 14.1 g:L^(-1) with the error between the experimental and predicted values less than 5%.The results of the multi-objective optimization reveal the synergistic and competitive relationship between biomass,lipid concentration,and conversion rate,which lay a basis for in-depth optimization and amplification.

关键词： microbial lipid machine learning artificial neural network support vector machine genetic algorithm

Progress in the application of graphene material in oilfield chemistry:A review

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Petroleum 2024年第2期10卷 175-190页

作者： Jinsheng Sun Yuanwei Sun Yong Lai Li Li Gang Yang Kaihe Lv Taifeng Zhang Xianfa Zhang Zonglun Wang Zhe Xu Zhiwen dai Jingping Liu School of Petroleum Engineering China University of Petroleum (East China) CNPC Engineering Technology r&d Company Limited Nanchong Vocational and Technical College Oil & Gas Technology research Institute of Changqing Oilfield Company CNPC Greatwall drilling Fluids Company

Graphene is a single atom thick crystal composed of carbon atoms. It is the lightest, thinnest, strongest material that conducts heat and electricity well heretofore. In terms of application, by introducing oxygen-containing groups, graphene can be well dispersed in solvents, can be chemically modified and functionalized, or connected with other electroactive substances through covalent bond or non-covalent bond to form composite materials, which is conducive to further processing and promotion. The application of graphene in oilfield chemistry started late, but developed rapidly. Graphene has played an active role in drilling fluid, cementing fluid, fracturing fluid, displacement fluid and other oilfield working fluids. It can enhance the temperature and salt resistance of working fluid and improve the effect of working fluid. In this paper, several directions of graphene applications in oilfield chemistry, such as modified graphene, graphene copolymers and graphene nanoparticles, are reviewed in detail from the synthesis methods, action mechanisms and effects of graphene and its derivatives, and the frontier cases at this stage are given. On the basis of the existing research, suggestions for the development direction of graphene materials in oilfield chemistry are given for a variety of graphene materials, aiming to provide guidance for the application of graphene in oilfield chemistry.

关键词： Oilfield chemistry Graphene Action mechanism Application Prospect

Heterovalent ion exclusion principle in atomically single site metal(hydr)oxide catalysts design

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Science Bulletin 2024年第13期69卷 2009-2012页

作者： daojin Zhou Fengmei Wang Yun Kuang Xiaoming Sun State Key Laboratory of Chemical resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Ocean Hydrogen Energy r&d Center Research Institute of Tsinghua University in ShenzhenShenzhen 518057China

Single-atom catalysts(SACs)are a series of catalysts in which all metal species are atomically dispersed on oxides,zeolites,sulfides,carbons,and so *** concept describing how atoms arrange with their nearest neighbors was proposed in 1969 by Van Hardeveld and co-workers[1],and researchers witness the growing popularity of SACs[2].However,the first long-standing issue in SACs is that the low concentration of active sites on the ***,weak chemical bonds between active sites with supports cannot sustain the functionalities of the SACs during long-term reactions,especially ones run at harsh conditions(high temperature or humidity,strong oxidative conditions).The loss or aggregation of active sites in SACs require substantial efforts to address the existing drawbacks in traditional SACs.

关键词： atomic bonds valent

超薄锡掺杂氧化镓结合高k栅介质:硅基兼容的4英寸功率场效应晶体管阵列

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Science Bulletin 2024年第12期69卷 1848-1851页

作者：刘子淳李佳诚杨惠霞杨涵黄元张逸韵黎沛涛马远骁王业亮 School of Integrated Circuits and Electronics and Yangtze delta region Academy Beijing Institute of TechnologyBeijing 100081China department of Electrical and Electronic Engineering The University of Hong KongHong Kong 999077China r&d Center for Solid-state Lighting Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

Gallium oxide(Ga_(2)O_(3)),a novel ultrawide-bandgap(UWBG)semiconductor,has attracted considerable attention owing to its large bandgap of up to 4.9 eV,a high breakdown electric field of 8 MV/cm,and a high Baliga's figure of merit exceeding 3000[1,2].These remarkable properties strongly support its potential applications in power electronics,extreme environmentresistance devices,and solar-blind detectors[1–3].

关键词：功率场效应晶体管高k栅介质氧化镓

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rational manipulation of electrolyte to induce homogeneous SEI on hard carbon anode for sodium-ion battery

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Journal of Energy Chemistry 2024年第7期94卷 414-429页

作者： Lu Liu Lingling Xiao Zhi Sun Shahid Bashir ramesh Kasi Yonghong Gu ramesh Subramaniam research Center for Clean Utilization Technology Phosphorous resources Hubei Three Gorges PolytechnicYichang 443000HubeiChina department of Physics Faculty of ScienceUniversiti MalayaKuala Lumpur 50603Malaysia UM Power Energy dedicated Advanced centre(UMPEdAC) Level 4Wisma R&DUniversiti MalayaKuala Lumpur 59990Malaysia department of Chemistry Saveetha School of EngineeringInstitute of Medical and Technical ScienceSaveetha UniversityChennai 602105TamilnaduIndia

Sodium-ion batteries (SIBs) have great potential to be the next major energy storage devices due to their obvious advantages and developing advanced electrodes and electrolytes is urgently necessary to promote its future ***,hard carbon as a state-of-the-art anode of SIBs still suffers from the low initial Coulomb efficiency and unsatisfactory rate capability,which could be improved by forming desirable solid electrolyte interphases (SEI) to some ***,the chemistry and morphology of these interfacial layers are fundamental parameters affecting the overall battery operation,and optimizing the electrolyte to dictate the quality of SEI on hard carbon is a key ***,this review summarizes the recent research on SEI design by electrolyte manipulation from solvents,salts,and *** also presents some potential mechanisms of SEI formation in various electrolyte ***,the current advanced characterization techniques for electrolyte and SEI structure analyses have been comprehensively ***,current challenges and future perspectives of SEI formation on hard carbon anode for SIBs are provided from the viewpoints of its compositions,evolution processes,structures,and characterization techniques,which will promote SEI efficient manipulation and improve the performance of hard carbon,and further contribute to the development of SIBs.

关键词： SEI Electrolyte optimization Hard carbon Electrochemical performance Sodium-ion batteries

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A rapid field crop data collection method for complexity cropping patterns using UAV and YOLOv3

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Frontiers of Earth Science 2024年第1期18卷 242-255页

作者： Huifang ZHANG Binyao WANG Zhonggang TANG Jiahui XUE ruihang CHEN Hongcheng KAN Shumiao LU Lina FENG Ye HE Shuhua YI Institute of Fragile Eco-environment Nantong UniversityNantong 226019China School of Geographic Science Nantong UniversityNantong 226019China Nantong Key Laboratory of Spatial Information Technology r&d and Application School of Geographic ScienceNantong UniversityNantong 226019China

Crop type mapping using remote sensing is critical for global agricultural monitoring and food ***,the complexity of crop planting patternsand spatial heterogeneity pose significant challenges to field data collection,thereby limiting the accuracy of remotely sensed crop *** study proposed a new approach for rapidly collecting field crop data by integrating unmanned aerial vehicle(UAV)images with the YOLOv3(You Only Look Once version 3)*** impacts of UAV flight altitude and the number of training samples on the accuracy of crop identification models were investigated using peanut,soybean,and maize as *** results showed that the average Fl-score for crop type detection accuracy reached 0.91 when utilizing UAV images captured at an altitude of 20 *** addition,a positive correlation was observed between identification accuracy and the number of training *** model developed in this study can rapidly and automatically identify crop types from UAV images,which significantly improves the survey efficiency and provides an innovative solution for acquiring field crop data in large areas.

关键词： deep learning flight altitude crop survey peanut soybean maize

MoS_(2) nanoflowers and PEdOT:PSS nanocomposite enabling wearable dual-mode pressure sensors

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Science China(Technological Sciences) 2024年第6期67卷 1737-1747页

作者： WANG FengMing YANG WeiJia MA Ke SHEN GengZhe SU daoJian LI BaiJun WANG ShuangPeng QIN BoLong ZHANG Chi XIN Yue CAO XiaoBing HE Xin School of Applied Physics and Materials Wuyi UniversityJiangmen529020China Biomaterials r&d Center Zhuhai Institute of Advanced TechnologyChinese Academy of SciencesZhuhai519003China Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoMacao999078China

A versatile sensing platform employing inorganic MoS_(2) nanoflowers and organic poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate)(PEdOT:PSS)has been investigated to develop the resistive and capacitive force-sensitive *** microstructure of the sensing layer heightens the sensitivity and response time of the dual-mode pressure sensors by augmenting electron pathways and inner stress in response to mechanical ***,the capacitive and resistive sensors exhibit sensitivities of 0.37 and 0.12 kPa^(-1),respectively,while demonstrating a remarkable response time of approximately 100 ***,it is noteworthy that the PEdOT:PSS layer exhibits excellent adhesion to polydimethylsiloxane(PdMS)substrates,which contributes to the development of highly robust force-sensitive sensors capable of enduring more than 10000loading/unloading *** combination of MoS_(2)/PEdOT:PSS layers in these dual-mode sensors has shown promising results in detecting human joint movements and subtle physiological ***,the sensors have achieved a remarkable precision rate of 98%in identifying target *** outcomes underscore the significant potential of these sensors for integration into applications such as electronic skin and human-machine interaction.

关键词： MoS_(2)/PEdOT:PSS nanocomposite force-sensitive sensor multi-scaled microstructure physiological signals monitoring object grasping recognition

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