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In situ characterization of particle formation in spray flame synthesis using wide-angle light scattering

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Particuology 2024年第3期86卷 304-312页

作者： Simon Aβmann franz J.T.Huber Stefan Will Lehrstuhl für Technische Thermodynamik(LTT) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91058Germany Erlangen Graduate Schoolin Advanced Optical Technologies(SAOT) Friedrich-Alexander-Universitat Erlangen-Nurnberg(FAU)Erlangen91052Germany Competence Unit Engineering of Advanced Materials(EAM) Friedrich-Alexander-Universitat Erlangen-Nürnberg(FAU)Erlangen91052Germany

Wide-angle light scattering(WALS)was used for in situ measurements of droplet and nanoparticle size distributions during the synthesis of titania and iron oxide particles from liquid precursor solutions in the standardized SpraySyn burner for spray flame *** was synthesized from titanium tetraisopropoxide(TTIP)and iron oxide from iron(II)nitrate nonahydrate(INN)using ethanol(EtOH)as *** images were taken at heights up to 120 mm above the burner surface and classified into droplet and particle *** size distributions were derived from a sequential analysis of scattering data containing the oscillating Mie pattern,the lognormal size distribution parameters for spherical and fractal particle fractions from a multivariate approach on averaged particle scattering *** results show that the precursor addition leads to altered evaporation behavior and even droplet disruption probably induced by puffing or micro-explosions compared to pure *** the case of TTIP(a hygroscopic alkoxide),the synthesis of a large fraction of spheres was observed,while the nitrate INN leads to the formation of mostly fractal aggregates.

关键词： Spray flame synthesis Metal oxide particles Elastic light scattering Droplet size distribution Nanoparticle morphology Particle size distribution

Autonomous Vehicle Platoons In Urban Road Networks:A Joint Distributed Reinforcement Learning and Model Predictive Control Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 141-156页

作者： Luigi D’Alfonso Francesco Giannini Giuseppe franzè Giuseppe Fedele Francesco Pupo Giancarlo Fortino IEEE the Department of Computer Engineering ModelingElectronics and SystemsUniversitàdella CalabriaVia Pietro BucciCubo 42-CRende(CS)87036Italy the Department of Mechanical Engineering Energy Engineering and ManagementUniversitàdella CalabriaVia Pietro BucciCubo 42-CRende(CS)87036Italy

In this paper, platoons of autonomous vehicles operating in urban road networks are considered. From a methodological point of view, the problem of interest consists of formally characterizing vehicle state trajectory tubes by means of routing decisions complying with traffic congestion criteria. To this end, a novel distributed control architecture is conceived by taking advantage of two methodologies: deep reinforcement learning and model predictive control. On one hand, the routing decisions are obtained by using a distributed reinforcement learning algorithm that exploits available traffic data at each road junction. On the other hand, a bank of model predictive controllers is in charge of computing the more adequate control action for each involved vehicle. Such tasks are here combined into a single framework:the deep reinforcement learning output(action) is translated into a set-point to be tracked by the model predictive controller;conversely, the current vehicle position, resulting from the application of the control move, is exploited by the deep reinforcement learning unit for improving its reliability. The main novelty of the proposed solution lies in its hybrid nature: on one hand it fully exploits deep reinforcement learning capabilities for decisionmaking purposes;on the other hand, time-varying hard constraints are always satisfied during the dynamical platoon evolution imposed by the computed routing decisions. To efficiently evaluate the performance of the proposed control architecture, a co-design procedure, involving the SUMO and MATLAB platforms, is implemented so that complex operating environments can be used, and the information coming from road maps(links,junctions, obstacles, semaphores, etc.) and vehicle state trajectories can be shared and exchanged. Finally by considering as operating scenario a real entire city block and a platoon of eleven vehicles described by double-integrator models, several simulations have been performed with the a

关键词： Distributed model predictive control distributed reinforcement learning routing decisions urban road networks

Laser-induced plasma formation in water with up to 400 mJ double-pulse LIBS

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Plasma Science and Technology 2024年第1期26卷 93-100页

作者： Marion HENKEL Michelle SIEMENS Ralf METHLING Benjamin EMDE Jörg HERMSDORF Steffen FRANKE Diego GONZALEZ Leibniz Institute for Plasma Science and Technology(INP) Felix-Hausdorff-Straße 2Greifswald 17489Germany Laser Zentrum Hannover e.V.(LZH) Hollerithallee 8Hannover 30419Germany

Double-pulse LIBS is a promising technique for deep-sea *** measurements in shallow water with up to 400 mJ each pulse were done to select laser parameters which promote optimized spectral line emission from plasma even at elevated pressures,where line broadening until loss of most of the spectral information can *** emission spectroscopy,using a Czerny-Turner spectrometer,has been applied to investigate the dependence of the emitted radiation on laser parameters and hydrostatic *** has been found,that higher laser pulse energies,especially with short pulse delay as required in high water pressure,can also have an adverse effect on the measured spectrum.

关键词： double-pulse LIBS underwater plasma formation emission spectrosocpy

Graphene-calcium carbonate coating to improve the degradation resistance and mechanical integrity of a biodegradable implant

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Journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： Lokesh Choudhary Parama Chakraborty Banerjee R.K.Singh Raman Derrek E.Lobo Christopher D.Easton Mainak Majumder Frank Witte Jörg F.Löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering Laboratory(NSEL) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIRO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia Julius Wolff Institute and Berlin Brandenburg Center for Regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany Laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body *** necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical *** this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(rgO)-calcium carbonate(CaCO_(3))composite *** analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David I.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest Sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNIO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain Swiss Federal Institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CSIRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield Science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain IuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of Silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian State Institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. In this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic ***: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to *** methods and information theory were used to select the best ***: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their ***: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of th

关键词： Competition coefficient Competition reduction Interspecific competition Intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

Subpopulations of regulatory T cells are associated with subclinical atherosclerotic plaques,levels of LDL,and cardiorespiratory fitness in the elderly

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Journal of Sport and Health Science 2024年第3期13卷 288-296,I0002页

作者： Tim Böttrich Pascal Bauer Vincent Gröβer Magdalena Huber Hartmann Raifer Torsten Frech Svenja Nolte Theresa Dombrowski franz Cemic Natascha Sommer Robert Ringseis Klaus Eder Karsten Krüger Christopher Weyh Department of Exercise Physiology and Sports Therapy Institute of Sports ScienceJustus-Liebig-UniversityGiessen 35394Germany Department of Cardiology and Angiology Justus-Liebig-University GiessenGiessen 35392Germany Institute for Systems Immunology Center for Tumor und ImmunologyMarburg 35032Germany TH Mittelhessen Department of Computer ScienceUniversity of Applied Sciences GiessenGiessen 35390Germany Department of Internal Medicine Universities of Giessen and Marburg Lung Center(UGMLC)Member of the German Center for Lung Research(DZL)Giessen 35394Germany Excellence Cluster Cardio-Pulmonary Institute(CPI) Justus-Liebig UniversityGiessen 35394Germany Institute of Animal Nutrition and Nutrition Physiology Justus-Liebig-University GiessenGiessen 35390Germany

Background:Atherosclerosis forms the pathological basis for the development of cardiovascular *** pathological processes initially develop without clinically relevant symptoms,the identification of early markers in the subclinical stage plays an important role for initiating early *** is evidence that regulatory T cells(Tregs)are involved in the development of ***,the present study aimed to identify and investigate associations with Tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques(SAP).In addition,various lifestyle and risk factors,such as cardiorespiratory fitness,were investigated as associated ***:A cross-sectional study was performed in 79 participants(male:n=50;age=63.6±3.7 years;body mass index=24.9±3.1 kg/m2;mean±SD)who had no previous diagnosis of chronic disease and were not taking *** of the carotids to identify SAP,cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were ***,tests were conducted to assess blood lipids and determine glucose *** of Tregs and their subtypes(resting(rTregs)and effector/memory(mTregs))was performed by 8-chanel flow *** were categorized according to atherosclerotic plaque *** and logistic regression models were used to analyze associations between ***:SAP was detected in a total of 29 *** participants with plaque were older(64.8±3.6 years vs.62.9±3.5 years)and had higher peripheral systolic blood pressure(133.8±14.7 mmHg vs.125.8±10.9 mmHg).The participants with SAP were characterized by a lower percentage of rTregs(28.8%±10.7%vs.34.6%±10.7%)and a higher percentage of mTregs(40.3%±14.7%vs.30.0%±11.9%).Multiple logistic regression identified age(odds ratio(OR)=1.20(95%confidence interval(95%CI):1.011.42))and

关键词： Cardiorespiratory fitness Elderly Regulatory T cells Subclinical atherosclerosis

Customized molecular tools to strengthen metabolic engineering of cyanobacteria

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Green Carbon 2024年第2期2卷 149-163页

作者： Stephan Klähn franz Opel Wolfgang R.Hess Department of Solar Materials Biotechnology Helmholtz Centre for Environmental Research–UFZLeipzig 04318Germany Genetics and Experimental Bioinformatics Albert-Ludwig University FreiburgFreiburg im Breisgau 79104Germany

Cyanobacteria are promising oxygenic phototrophs for the production of various *** their(photo)biotechnological exploitation,molecular tools are required,such as,for the introduction and expression of heterologous genes,or the modulation of enzyme activities or entire *** and strategies for the development of photosynthetic biomanufacturing technologies based on cyanobacteria have been extensively reviewed,as well as certain specialized aspects of their genetic ***,options for metabolic engineering of specific cyanobacterial cells are still less developed than those for other bacteria of biotechnological *** addition to the standard genetic toolbox for“classical”metabolic engineering,we emphasize certain aspects,including recently developed vector systems for the extrachromosomal maintenance of genes and approaches based on clustered regularly interspaced short palindromic repeats(CRISPR)*** highlight the development of custom molecular tools for specific strains or products,discuss the emerging use of small regulatory proteins that appear promising for advanced metabolic engineering approaches to promote specific product formation,and provide an overview of suitable online ***,we discuss the current trends in this field and indicate their potential,such as using suitable product sensors that enable systematic screening,and optimization approaches.

关键词： Metabolic engineering Cyanobacteria Synthetic plasmids Regulatory proteins Sensors

Towards greener polymers:Trends in the German chemical industry

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Green Carbon 2024年第1期2卷 33-44页

作者： Adam W.franz Stefan Buchholz Rolf W.Albach Rolf Schmid BASF SE Ludwigshafen 67056Germany Evonik Operations GmbH Hanau 63457Germany Association for Chemistry and Economics German Chemical SocietyFrankfurt am Main 60444Germany Stuttgart University and Bio4Business Stuttgart 70569Germany

Global plastics production is expected to exceed 400 million tons and reach 600 million tons by *** synthesis currently accounts for approximately 3%of global greenhouse gas *** 60%of all polymers are produced for *** include shopping bags,packaging materials,mulch films,and soluble polymers for cosmetics and other ***,only a portion of single-use plastic is recycled or disposed of in incinerators or *** estimated 20%is not disposed of properly and pollutes the global environment,especially the *** response to these challenges,the United Nations,European Union,and many nation-states are developing regulatory frameworks that encourage the chemical industry to produce plastics with a smaller environmental footprint and often support this through research *** solutions include:(1)the use of green energy,green hydrogen,bio-based feedstocks,or CO_(2) in synthesis;(2)the reuse or recycling of plastics through conversion or pyrolysis;and(3)the production of biodegradable *** German chemical industry contributes approximately one-third of polymer production in the *** is embedded in the EU regulatory and research landscape and anchored in the European Green Deal,which aims for carbon neutrality by *** this paper,we describe how BASF and Evonik,two leading German chemical companies with strong but different polymer portfolios,respond to the call for greener polymers and how technologies are being developed to make polyurethanes,a particularly important and difficult-to-recycle family of elastomers and duromers,renewable and *** the environmental footprint of plastics requires not only innovative materials but also proper governance,regulatory and collection systems,and public willingness to *** an international comparison of these competencies,expressed by the"polymer management index"(PMI),Germany achieved a top position.

关键词： Plastics recycling Biobased plastics Biodegradable plastics Polymer management index European Green Deal

General Solutions of First-Order Algebraic ODEs in Simple Constant Extensions

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系统科学与复杂性学报:英文版 2023年第4期36卷 1769-1788页

作者： MITTERAMSKOGLER Johann Josef WINKLER franz Research Institute for Symbolic Computation(RISC) Johannes Kepler Universität LinzA-4040 LinzAustria

If a first-order algebraic ODE is defined over a certain differential field,then the most elementary solution class,in which one can hope to find a general solution,is given by the adjunction of a single arbitrary constant to this *** of this type give rise to a particular kind of generic point—a rational parametrization—of an algebraic curve which is associated in a natural way to the ODE’s defining *** for the opposite direction,we show that a suitable rational parametrization of the associated curve can be extended to a general solution of the ODE if and only if one can find a certain automorphism of the solution *** automorphisms are determined by linear rational functions,i.e.,Möbius *** properties of rational parametrizations,in combination with the particular shape of such automorphisms,lead to a number of necessary conditions on the existence of general solutions in this solution ***,the desired linear rational function can be determined by solving a comparatively simple differential system over the ODE’s field of *** results hold for arbitrary differential fields of characteristic zero.

关键词： Algebraic curve algebraic differential equation general solution Möbius transformation rational parametrization