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Stem radial Co_2 conductance affects stem respiratory Co_2 fluxes in ash and birch trees

Journal of Forestry research 2019年第1期30卷 21-29页

作者： Xiuwei Wang Zijun Mao M.A.McGuire r.o.teskey School of Forestry Northeast Forestry University Key Laboratory of Forest Plant Ecology of Ministry of Education Northeast Forestry University Warnell School of Forestry and Natural resources University of Georgia

The Co_2 released from respiring cells in woody tissues of trees can contribute to one of three fluxes:efflux to the atmosphere(E_A),internal xylem sap transport flux(F_T),and storage flux(DS).Adding those fluxes together provides an estimate of actual stem respiration(r_S).We know that the relative proportion of Co_2 in those fluxes varies greatly among tree species,but we do not yet have a clear understanding of the causes for this *** possible explanation is that species differ in stem radial Co_2 conductance(g_c).A high g_c would favor the E_A pathway and a low g_cwould favor the F_***,g_chas only been measured once in situ and only in a single tree *** measured g_cusing two methods in stems of Fraxinus mandshurica rupr.(ash)and Betula platyphylla Suk.(birch)trees in situ,along with r_S,E_A,F_T and *** radial Co_2 conductance was substantially greater in ash trees than in birch *** to that finding,in ash trees over 24 h,E_Aconstituted the entire flux of respired Co_2 ,and F_Twas negative,indicating that additional Co_2 ,probably transported from the root system via the xylem,was also diffusing into the *** ash trees,F_T was negative over the entire 24 h,and this study represents the first time that has been *** addition of xylem-transported Co_2 to E_A caused E_Ato be 9% higher than the actual r_Sover the diel measurement *** trees,which had lower g_c,also had a more commonly seen pattern,with E_A accounting for about 80% of the Co_2 released from local cell respiration and F_T accounting for the *** inorganic carbon concentration in xylem sap was also lower in ash trees than in birch trees:2.7 versus 5.3 mmol L^(-1),*** results indicate that stem Co_2 conductance could be a very useful measurement to help explain differences among species in the proportion of respired Co_2 that remains in the xylem or diffuses into the atmosphere.

关键词： Stem Co2 conductance Stem respiration Stem Co2 efflux Transport flux Stem temperature Sap flow Sap flux density

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Fast prediction of rain erosion in wind turbine blades using a data-based computational tool

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Journal of Hydrodynamics 2024年第3期36卷 504-518页

作者： Juan M.Gimenez Sergio r.Idelsohn Eugenio oñate Centre Internacional de Mètodes Numèrics en Enginyeria(CIMNE) Edifici C1 Campus Nord UPC C/Gran CapitàS/NBarcelonaSpain

Wind turbines(WTs)face a high risk of failure due to environmental factors like erosion,particularly in high-precipitation areas and offshore *** this paper we introduce a novel computational tool for the fast prediction of rain erosion damage on WT blades that is useful in operation and maintenance decision making *** approach is as follows:Pseudo-Direct Numerical Simulation(P-DNS)simulations of the droplet-laden flow around the blade section profile are employed to build a high-fidelity data set of impact statistics for potential operating *** this database as training data,a machine learning-based surrogate model provides the feature of the impact pattern over the 2-D section for given wind and rain *** this information,a fatigue-based model estimates the remaining lifetime and erosion damage for both homogeneous and coating-substrate blade *** prediction is done by quantifying the accumulated droplet impact energy and evaluating operative conditions over time periods for which the weather at the installation site is *** this work,we describe the modules that compose the prediction method,namely the database creation,the training of the surrogate model and their coupling to build the prediction ***,the method is applied to predict the remaining lifetime and erosion damage to the blade sections of a reference *** evaluate the reliability of the tool,several site locations(offshore,coastal,and inland),the coating material and the coating thickness of the blade are *** few minutes we are able to estimate erosion after many years of *** results are in good agreement with field observations,showing the promise of the new rain erosion prediction approach.

关键词： Wind turbine blades leading edge erosion fatigue Pseudo-Direct Numerical Simulation(P-DNS) machine learning eblader

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Assimilation of GoES-r Geostationary Lightning Mapper Flash Extent Density Data in GSI 3DVar, EnKF, and Hybrid En3DVar for the Analysis and Short-Term Forecast of a Supercell Storm Case

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Advances in Atmospheric Sciences 2024年第2期41卷 263-277页

作者： rong KoNG Ming XUE Edward r.MANSELL Chengsi LIU Alexandre o.FIErro Center for Analysis and Prediction of Storms Norman Oklahoma 73072U.S.A University of oklahoma Norman Oklahoma 73072U.S.A NoAA/National Severe Storms Laboratory NormanOklahoma 73072U.S A.4Zentralanstalt für Meteorologie und Geodynamik Department of Forecasting Models-ZAMGVienna 1190Austria

Capabilities to assimilate Geostationary operational Environmental Satellite “r-series ”(GoES-r) Geostationary Lightning Mapper(GLM) flash extent density(FED) data within the operational Gridpoint Statistical Interpolation ensemble Kalman filter(GSI-EnKF) framework were previously developed and tested with a mesoscale convective system(MCS) case. In this study, such capabilities are further developed to assimilate GoES GLM FED data within the GSI ensemble-variational(EnVar) hybrid data assimilation(DA) framework. The results of assimilating the GLM FED data using 3DVar, and pure En3DVar(PEn3DVar, using 100% ensemble covariance and no static covariance) are compared with those of EnKF/DfEnKF for a supercell storm case. The focus of this study is to validate the correctness and evaluate the performance of the new implementation rather than comparing the performance of FED DA among different DA schemes. only the results of 3DVar and pEn3DVar are examined and compared with EnKF/DfEnKF. Assimilation of a single FED observation shows that the magnitude and horizontal extent of the analysis increments from PEn3DVar are generally larger than from EnKF, which is mainly caused by using different localization strategies in EnFK/DfEnKF and PEn3DVar as well as the integration limits of the graupel mass in the observation operator. overall, the forecast performance of PEn3DVar is comparable to EnKF/DfEnKF, suggesting correct implementation.

关键词： GoES-r lightning data assimilation EnKF EnVar

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Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

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Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina r.Gasilova Daria N.Poshina Aleksandra o.Sitnikova Natalia N.Saprykina Yury A.Skorik Institute of Macromolecular Compounds of the russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—oSo3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcoH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcoH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%ron microscopy and atomic force microscopy images of dried samples were discussed in relation to the light scattering results.

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan Light scattering

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Europium recovery process by means of polymeric nanoparticles functionalized with acrylic acid,curcumin and fumaramide

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Journal of rare Earths 2024年第10期42卷 1950-1959页

作者： P.A.Martínez-Montoya J.M del río A.de J.Morales-ramirez M.Corea Escuela Superior de Ingeniería Química e Industrias Extractivas ESIQIE-IPNDepartamento de Ingeniería Metalúrgica UPALM S/N Col.LindavistaGustao A.MaderoCDMXC.P.07738Mexico Escuela Superior de Ingenieria Química e Industrias Extractivas ESIQIE-IPNLaboratorio de Investigación en Polímeros y NanomaterialesUPALM S/N Col.LindavistaGustavoA.MaderoCDMXC.P.07738Mexico Centra de Investigación e Innovación Tecnológica CIITEC-IPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P.02250CDMXMexico

Polymeric nanoparticles of poly(methyl methacrylate)were obtained by emulsion polymerization techniques in a proce ss of two *** particles were functionalized with acrylic acid,curcumin,and fumaramide and three series of polymeric particles were *** incorporation of functional groups was confirmed by Fourier transform-infrared spectrosocopy(FT-Ir)and ultraviolet-visible(UV-Vis)*** spherical morphology of particles with an average diameter of 100 nm was observed by scartning electron microscopy(SEM).The polymeric materials were used for recovery of[Eu]from synthetic *** nanoparticles show excellent chelation capacity to trap rare-earth ions,because they recover more than 85%of[Eu]at pH of *** images of SEM after extraction process show arrays between particles with larger average particle sizes to 1.5 *** addition,the particles have a good stripping capacity,exceeding 50%of it,maintaining their homogeneity in morphology and good stability in dispersion for the recovery and stripping processes.A pseudo-second model order is obtained for the extraction and stripping processes while the best results of stripping process are obtained at pH of 6.

关键词： [Eu]recovery Chelating effect Extraction process Stripping process Emulsion polymerization rare earths

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optimizing building retrofit through data analytics:A study of multi-objective optimization and surrogate models derived from energy performance certificates

Energy and Built Environment

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Energy and Built Environment 2024年第6期5卷 889-899页

作者： G.r.Araújo ricardo Gomes Paulo Ferrão M.Glória Gomes IN+ DEMTécnico LisboaUniversidade de lisboaAv Rovisco PaisLisboa1049-001Portugal CErIS DECivilTécnico LisboaUniversidade de LisboaAv Rovisco PaisLisboa1049-001Portugal

The building stock is responsible for a large share of global energy consumption and greenhouse gas emissions,therefore,it is critical to promote building retrofit to achieve the proposed carbon and energy neutrality *** of the policies implemented in recent years was the Energy Performance Certificate(EPC)policy,which proposes building stock benchmarking to identify buildings that require ***,research shows that these mechanisms fail to engage stakeholders in the retrofit process because it is widely seen as a mandatory and complex *** study makes use of an EPC database to integrate machine learning techniques with multi-objective optimization and develop an interface capable of(1)predicting a building’s,or household’s,energy needs;and(2)providing the user with optimum retrofit solutions,costs,and return on *** goal is to provide an open-source,easy-to-use interface that guides the user in the building retrofit *** energy and EPC prediction models show a coefficient of determination(r2)of 0.84 and 0.79,and the optimization results for one case study EPC with a 2000€budget limit inÉvora,Portugal,show decreases of up to 60%in energy needs and return on investments of up to 7 in 3 years.

关键词： Building energy performance Building optimization Multi-objective surrogate models Building retrofitting

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Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry o El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula

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Sensing nanoscale electromagnetic forces when the heat is on

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National Science review 2024年第7期11卷 64-65页

作者： Eric o.Potma Department of Chemistry University of California

In scanning probe microscopy(SPM),a sharp tip scans across a sample to produce an image with nanometer-scale resolution or better. SPM contrast is derived from the physical interplay between the tip and the sample. A special class of SPM techniques measures forces when the tip–sample junction is illuminated by an external light source. Photo-induced forces can be sensitive to the optical properties of the sample, thus enabling nanoscale imaging with spectroscopic,material-specific contrast.

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A 3D In-vitro model of the human dentine interface shows long-range osteoinduction from the dentine surface

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International Journal of oral Science 2024年第2期16卷 225-237页

作者： William Macalester Asme Boussahel rafael o.Moreno-Tortolero Mark r.Shannon Nicola West Darryl Hill Adam Perriman School of Cellular and Molecular Medicine Biomedical Sciences BuildingUniversity of BristolUniversity WalkBristolUnited Kingdom Bristol Centre for Functional Nanomaterials HH Wills Physics LaboratoryUniversity of BristolTyndall AvenueBristolUnited Kingdom Centre for Protolife research School of ChemistryUniversity of BristolCantocks CloseBristolUnited Kingdom Max Planck-Bristol Centre for Minimal Biology School of ChemistryUniversity of BristolBristolUnited Kingdom Periodontology Bristol Dental SchoolUniversity of BristolLower Maudlin StreetBristolUnited Kingdom

Emerging regenerative cell therapies for alveolar bone loss have begun to explore the use of cell laden hydrogels for minimally invasive surgery to treat small and spatially complex maxilla-oral ***,the oral cavity presents a unique and challenging environment for in vivo bone tissue engineering,exhibiting both hard and soft periodontal tissue as well as acting as key biocenosis for many distinct microbial communities that interact with both the external environment and internal body systems,which will impact on cell fate and subsequent treatment ***,we design and bioprint a facile 3D in vitro model of a human dentine interface to probe the effect of the dentine surface on human mesenchymal stem cells(hMSCs)encapsulated in a microporous hydrogel *** demonstrate that the dentine substrate induces osteogenic differentiation of encapsulated hMSCs,and that both dentine andβ-tricalcium phosphate substrates stimulate extracellular matrix production and maturation at the gel-media interface,which is distal to the gel-substrate *** findings demonstrate the potential for long-range effects on stem cells by mineralized surfaces during bone tissue engineering and provide a framework for the rapid development of 3D dentine-bone interface models.

关键词： interface den surface

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Generation of lossy mode resonances(LMr)using perovskite nanofilms

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opto-Electronic Advances 2024年第2期7卷 33-40页

作者： Dayron Armas Ignacio r.Matias M.Carmen Lopez-Gonzalez Carlos ruiz Zamarreño Pablo Zubiate Ignacio del Villar Beatriz romero Electrical Electronic and Communications Engineering DepartmentPublic University of NavarraPamplona 31006Spain Institute of Smart Cities(ISC) Public University of NavarraPamplona 31006Spain Experimental Science and Technology School Rey Juan Carlos UniversityMostoles 28933Spain

The results presented here show for the first time the experimental demonstration of the fabrication of lossy mode resonance(LMr) devices based on perovskite coatings deposited on planar waveguides. Perovskite thin films have been obtained by means of the spin coating technique and their presence was confirmed by ellipsometry, scanning electron microscopy, and X-ray diffraction testing. The LMrs can be generated in a wide wavelength range and the experimental results agree with the theoretical simulations. overall, this study highlights the potential of perovskite thin films for the development of novel LMr-based devices that can be used for environmental monitoring, industrial sensing, and gas detection, among other applications.

关键词： perovskite thin films slab waveguide lossy mode resonance

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