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Using fracture-based continuum modeling of coupled geomechanical-hydrological processes for numerical simulation of hydraulic fracturing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1582-1599页

作者： Goodluck i.Ofoegbu GNO Modeling Research llC. San AntonioTX78253USA

This paper describes numerical simulation of hydraulic fracturing using fracture-based continuum modeling(FBCM)of coupled geomechanical-hydrological processes to evaluate a technique for high-density fracturing and fracture *** simulations are innovative because of modeling discrete fractures explicitly in continuum analysis.A key advantage of FBCM is that fracture initiation and propagation are modeled explicitly without changing the domain grid(*** re-meshing).Further,multiple realizations of a preexisting fracture distribution can be analyzed using the same domain *** simulated hydraulic fracturing technique consists of pressurizing multiple wells simultaneously:initially without permeating fluids into the rock,to seed fractures uniformly and at high density in the wall rock of the wells;followed by fluid injection to propagate the seeded fracture density *** combines the ease of continuum modeling with the potential accuracy of modeling discrete fractures and fracturing *** are modeled as piecewise planar based on intersections with domain elements;fracture geometry stored as continuum properties is used to calculate parameters needed to model individual fractures;and rock behavior is modeled through tensorial aggregation of the behavior of discrete fractures and unfractured *** are presented for previously unfractured rock and for rock with preexisting fractures of horizontal,shallow-dipping,steeply dipping,or vertical *** of a single-well model are used to determine the pattern and spacing for a multiple-well *** results illustrate high-density fracturing and fracture caging through simultaneous fluid injection in multiple wells:for previously unfractured rock or rock with preexisting shallow-dipping or horizontal fractures,and in situ vertical compressive stress greater than *** preexisting fractures are steeply dipping or vertical,and considering the same in situ

关键词： Discrete fracture Fracture-based continuum modeling Fracture caging High-density fracturing Hydraulic fracturing Preexisting fracture

Metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The innovation 2024年第2期5卷 107-114页

作者： Johan Gustafsson Fariba Roshanzamir Anders Hagnestål Sagar M.Patel Oseeyi i.Daudu Donald F.Becker Jonathan l.Robinson Jens Nielsen Department of life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden Department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA Bioinnovation institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in ***-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell ***,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion *** addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human *** combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer *** identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was *** work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

Electro-Optical Model of Soiling Effects on Photovoltaic Panels and Performance implications

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Energy Engineering 2024年第2期121卷 243-258页

作者： A.Asbayou G.P.Smestad i.ismail A.Soussi A.Elfanaoui l.Bouhouch A.ihlal laboratory of Materials and Renewable Energies University Ibn ZohrAgadir80000Morocco Sol ideas Technology Development San José95150USA

in this paper,a detailed model of a photovoltaic(PV)panel is used to study the accumulation of dust on solar *** presence of dust diminishes the incident light intensity penetrating the panel’s cover glass,as it increases the reflection of light by *** phenomenon,commonly known as the“soiling effect”,presents a significant challenge to PV systems on a global *** basic models of the equivalent circuits of a solar cell can be found,namely the single-diode model and the two-diode *** limitation of efficiency data in manufacturers’datasheets has encouraged us to develop an equivalent electrical model that is efficient under dust conditions,integrated with optical transmittance considerations to investigate the soiling *** proposed approach is based on the use of experimental current-voltage(i-V)characteristics with simulated data using MATlAB/*** research outcomes underscores the feasibility of accurately quantifying the reduction in energy production resulting from soiling by assessing the optical transmittance of accumulated dust on the surface of PV glass.

关键词： Photovoltaics solar energy optical transmittance soiling dust PV performance

Effect of Ta_(2)O_(5)nanoparticles on bioactivity,composition,structure,in vitro and in vivo behavior of PEO coatings on Mg-alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2360-2379页

作者： D.V.Mashtalyar i.M.imshinetskiy V.V.Kashepa K.V.Nadaraia M.A.Piatkova A.i.Pleshkova K.A.Fomenko A.Yu.Ustinov S.l.Sinebryukhov S.V.Gnedenkov institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok690022Russia Far Eastern Federal University Vladivostok690950Russia Regional Clinical Dermatovenerological Dispensary Vladivostok690033Russia

The present study investigates the physical and chemical characteristics,behavior in vitro and in vivo,and biocompatibility of coatings containing Ta_(2)O_(5),which are obtained by plasma electrolytic oxidation(PEO)on MA8 magnesium *** obtained coatings demonstrate in vivo biocompatibility and in vitro *** to the base PEO coating,the layers containing Ta_(2)O_(5)facilitate the development of apatite in simulated body fluid,suggesting that the inclusion of nanoparticles improves bioactivity of the *** was found that incorporation of Ta_(2)O_(5)nanoparticles increases roughness and porosity of the formed layers by increasing particle concentration in electrolytes for the PEO process contributing to sufficient soft tissue ingrowth in *** on in vivo studies,these coatings also provide favorable tissue response and minimal inflammatory reaction in comparison with the bare magnesium alloy due to protection of living tissues from deleterious corrosion events of magnesium implant such as local alkalization and intense hydrogen *** results obtained in the present study concluded biocompatibility,tissue integration of the PEO coatings containing Ta_(2)O_(5)nanoparticles making them a promising protective layer for biodegradable magnesium implants.

关键词： Plasma electrolytic oxidation Bioactive coatings Tantalum pentoxide Simulated body fluid(SBF) Apatite formation Histology

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Kinetics and mechanism of the low-energy b-a phase transition of the second kind in 2,4-dinitroanisole

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Defence Technology（防务技术） 2024年第10期40卷 210-224页

作者： Aleksandr V.Stankevich Nikolay A.Rasputin Anisa KhRudina Gennady l.Rusinov Vera i.Filyakova Valery N.Charushin y1.postovsky institute of organic synthesis ural branch of the russian academy of sciencesekaterinburg 620108russia russian federal nuclear center e zababakhin all-russia research institute of technical physics snezhinsk 456770russia kazan national research technological university kazan 420015russia

in this work,comprehensive studies of 2,4-dinitroanisole(2,4DNAN)were carried out using powder thermorentgenography of the internal *** time of the complete polymorphic transition in the solid phase b/a in 2,4DNAN under various combinations of conditions has been *** has been established that,regardless of the season of manufacture of the substance,when it is stored for 8e9 months,with a change in ambient temperature from minus 30℃ to plus 30℃,a complete polymorphic transition b/a *** stored in conditions below minus 5℃,polymorphic transition does not *** stored in conditions above plus 30℃ in a closed container,polymorphic transition occurs within 3 *** polymorphic transition is accompanied by a decrease in density by 1.3%e1.5%and an increase in melting temperature by 10-12℃,depending on the degree of purity of the starting *** activation energy of the molecular rearrangement was 68e70 kJ/mol(16.5±3 kcal/mol).The mechanism of polymorphic transition has been evaluated,which is presumably based on internal homodiffusion and energy transfer to the surface of the mass of powder particles and the *** average activation energy of the polymorphic transition process was 110±6.2 kJ/mol(26.2 kcal/mol).in an open container,reactions proceed by a homogeneous mechanism,and in a closed container by a heterogeneous mechanism involving the gas phase.

关键词： Energetic materials Melt-castable 2,4-Dinitroanisole Polymorphic transition Kinetics Mechanism Homodiffusion Sublimation

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A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications

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Bio-Design and Manufacturing 2024年第3期7卷 277-291页

作者： i.A.O.Beeren G.Dos Santos P.J.Dijkstra C.Mota J.Bauer H.Ferreira Rui l.Reis N.Neves S.Camarero-Espinosa M.B.Baker l.Moroni Department of Complex Tissue Regeneration MERLN Institute for Technology-Inspired Regenerative MedicineMaastricht University6229 ER MaastrichtThe Netherlands 3B’s Research Group I3Bs–Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal iCVS/3B’s-PT Government Associate laboratory 4806-909 Braga/GuimarãesPortugal POlYMAT University of the Basque Country UPV/EHU20018 Donostia/San SebastiánSpain iKERBASQUE Basque Foundation for Science48009 BilbaoSpain

Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering ***,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell *** of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface ***,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(PCl5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight PCl75k at different *** porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight PCl *** a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was *** two weeks of culturing in a basic medium,cells expressed higher levels of BMP receptor ii(BMPRii)on films with the conjugated *** addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface *** together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material ***,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(m

关键词： Additive manufacturing Blending Surface functionalization Surface density Click chemistry Human

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leading directions and effective distance of larch offspring dispersal at the upper treeline in the Northern and Polar Urals, Russia

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Forest Ecosystems 2024年第5期11卷 603-617页

作者： P.A.Moiseev V.l.Semerikov T.V.Semerikova D.S.Balakin i.B.Vorobiev S.O.Viuykhin institute of Plant and Animal Ecology Ural BranchRussian Academy of SciencesEkaterinburg620144Russia Center for Genetics and life Science Sirius University of Science and Technology354340SochiRussia

Climate has changed sufficiently over the last 150 years and forced out upper treeline advance at the most studied sites around the *** rate of advance has been extremely variable–from tens to hundreds meters in *** is because the degree at which tree frontal populations respond to climate change depends on the complex interaction of biological and physical *** resulting stand pattern is the consequence of the interaction between dispersal and survival functions.A few publications have addressed the question of how this pattern is *** order to understand how the spatial structure of tree stands was formed at the upper limit of their distribution in the Ural Mountains,we assessed the distance and direction of dispersal of offspring from maternal *** found that in frontal larix sibirica ***,‘effective’dispersal of offspring ranges from 3 to 758 m(with a median of 20–33 m in open forest and 219 m in single-tree tundra in the Polar Urals and 107 m in open forest in the Northern Urals).We revealed that most of the offspring effectively dispersed not only in the direction of the prevailing winds,but also in the opposite direction up the slope,and the distance can reach 500–760 *** data obtained can be used to develop an individual-based model which is capable of simulating in detail the dynamics of tree stands at the upper limit of their growth and reliably predicting the future position and pattern of treeline ecotone as growth conditions continue to improve in the face of observed climate change.

关键词： Effective dispersal distance Upper treeline Parentage analysis Age estimation Terrestrial laser scanning larix sibirica Ural mountains

Measuring impact of lean Manufacturing Tools for Continuous improvement on Economic Sustainability

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Journal of Systems Science and Systems Engineering 2024年第4期33卷 452-474页

作者： luis Javier Márquez Figueroa Jorge luis García-Alcaraz Ahmed i.Osman Alfonso Jesús Gil lópez Yashar Aryanfar Mika Sillanpää Mamdouh El Haj Assad Department of Electrical Engineering and Computer Science Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico Department of industrial Engineering and Manufacturing Universidad Autónoma de Ciudad JuárezCiudad JuárezChihuahuaMéxico School of Chemistry and Chemical Engineering Queens UniversityBelfastNorthern IrelandUK Department of Economic and Managerial Sciences University of La RiojaLa RiojaSpain Department of Chemical Engineering University of JohannesburgJohannesburgSouth Africa Department of Sustainable and Renewable Energy Engineering University of SharjahSharjahUAE

Using lean Manufacturing(lM)tools in production processes is crucial for companies’economic,environmental,and social sustainability *** study shows a structural equation model(SEM)that shows the relationship between lM Tools like Kaizen(KAi),Gemba(GEM),Value Stream Mapping(VSM)and Key Performance indicator(KPi)with Economic Sustainability(ECS).Seven hypotheses were evaluated with data from 179 responses to a questionnaire about the Mexican maquiladora industry,showing that these variables are *** a 95%confidence level,the model was evaluated using the partial least squares *** findings indicate that the relationships between KAi and GEM and KAi and VSM have the strongest relationship,followed by VSM and ECS;however,VSM has the strongest effect on *** on these findings,it is recommended that managers adopt a continuous improvement(KAi)approach based on working directly on the shop floor(GEM and VSM)to support their decisions regarding economic growth(ECS).

关键词： lean manufacturing economic sustainability structural equation model quality improvement

Taxonomy,distribution,and contemporary exposure of terrestrial mammals to floods and human pressure across different areas for biodiversity conservation in China

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integrative Zoology 2024年第3期19卷 458-467页

作者： Roman SHARNUUD Eric i.AMECA MOE Key laboratory for Biodiversity Science&Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijingChina Climate Change Specialist Group Species Survival CommissionInternational Union for Conservation of NatureGlandSwitzerland

A significant research focus is placed on identifying animal species and areas at future risk to human-induced alterations of the environment and long-term changes in climatic ***,the extent to which exposure to extreme climatic events and intense human pressure can increase the risk of harmful impacts on species remains poorly *** on terrestrial mammals in China,one of the world’s megadiverse countries,we investigated patterns of contemporary exposure to floods and human pressures and determined their taxonomic representation and distribution across three major area-based conservation schemes,namely,national nature reserves(NNRs),priority areas for biodiversity conservation(PABCs),and key biodiversity areas(KBAs).Among the 440 species assessed with moderate or high exposure to floods,327(∼75%)also qualified as moderate or high in exposure to intense human *** species mainly belong to the orders Chiroptera,Eulipotyphla,and ***,there were 305,311,and 311 species with moderate or high exposure to flood and intense human pressure represented across NNRs,PABCs,and KBAs,*** findings support the prioritization of KBAs for expansion of site-based protection efforts such as NNRs in China,considering threats to species from exposure to adverse effects from both extreme climate and human pressure.

关键词： conservation floods human pressure mammals taxonomy