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A unified electrical model based on experimental data to describe electrical transport in carbon nanotube-based materials

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Nano Research 2020年第6期13卷 1764-1779页

作者： Yoann Dini Jérôme Faure-Vincent jean Dijon Univ.Grenoble-Alpes CEALITENDTNMF-38000GrenobleFrance Univ.Grenoble-Alpes CEACNRSIRIGSyMMESF-38000GrenobleFrance

Understanding the electrical transport in carbon nanotube(CNT)materials is one key to reach very high electrical *** CNT material resistivity(ρ(T))as function of the temperature are fully apprehended by their reduced activation W(T)=dln(ρ)/dln(T)*** to now,no model accurately fits W(T)curves,thus preventing from precisely describing the CNT material electrical *** present a new electrical transport model that perfectly fits all W(T)curves found in the literature and in our own *** material resistivities are modeled byρ(T)=ρ0(T^−α+m(1+βTγT^2)).Our model has few enough parameters(α,m,β,γ)to relate them to the CNT *** 70 K,we experimentally show that CNT material resistivity follows the Luttinger Liquid theory justifying the T^−αterm in our *** 70 K,the polynomial part becomes dominant and depends on the two different CNT fabrication techniques which lead to two very different yarn *** yarns made from floating catalyst chemical vapor deposition CNTs,the polynomial is explained by the percolation of metallic CNT ***,the polynomial of yarns spun from CNT arrays is explained by the electrical transport in CNT bundles which are the basic building blocks of this type of yarns.

关键词： carbon nanotube carbon-based materials electrical conductivity electrical transport model Luttinger Liquid

Polysiloxane coatings on microspheres based on multiphase Flow with Interface Exchange-Discrete Element modelling

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Particuology 2022年第10期20卷 88-99页

作者： Sanjay Kumar Devendhar Singh jean-FranCois Dietiker Kathy Lu Department of materials Science and Engineering Virginia Polytechnic Institute and State UniversityBlacksburgVirginia 24061USA National Energy Technology Laboratory PittsburghPA 15236USA Leidos Research Support Team PittsburghPA 15236-0940USA

Polysiloxane coatings on yttria stabilized zirconia(YSZ)microspheres of 500μm were simulated in a spout fluidized bed coater using multiphase Flow with Interface Exchange-Discrete Element modelling(mFiX-DEm).Two different coater configurations were developed to study the influence of gas velocity and its distribution on particle *** presence of the Wurster tube not only enhances the dis-tribution but also increases the overall residence time of the *** were also carried out with different Wurster tube positions(normal,10%and 20%lowered from its initial position).Among these,20%lowered Wurster tube position demonstrated the most effective coating *** effects of gas inlet pressure on the average gas velocity and the distribution of particles were *** than 97%of the particles can be *** derived results,including average gas velocity,particle retention percentage,and distribution of particles with gas velocity,are being used to guide the experimental work in obtaining defect-free coatings for YSZ microspheres.

关键词： Spouted bed Wurster tube Coating Yttria stabilized zirconia(YSZ) mFiX

To forage or hide？ Threat-sensitive foraging behaviour in wild, non-reproductive passerine birds

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Current Zoology 2014年第6期60卷 719-728页

作者： Shaun TURNEY jean-Guy J. GODIN Department of Biology Carleton University Ottawa ON K1 S 5B6 Canada Department of Biology McGill University Montreal QC H3A 1B 1 Canada

Because antipredator behaviours are costly, the threat-sensitive predator avoidance hypothesis predicts that individual animals should express predator-avoidance behaviour proportionally to the perceived threat posed by the predator. Here, we experimentally tested this hypothesis by providing wild passerine birds supplemental food （on a raised feeding platform） at either 1 or 4 m from the edge of forest cover （potential refuge）, in either the presence or absence of a nearby simulated predation threat （a sharp-shinned hawk Accipiter striatus model）. Compared with the control treatment, we observed proportionally fewer bird visits to the food patch, and the birds took longer to re-emerge from forest refuge and return to feed at the food patch, after the hawk presentation than before it. The observed threat-sensitive latency-to-return response was stronger when the food patch was further away from the nearest refuge. Overall, our results are consistent with the predictions of the threat-sensitive predator avoidance hypothesis in that wild passerine birds （primarily black-capped chickadees Poecile atricapillus） exhibited more intense antipre- dator behavioural responses with increasing level of apparent threat. The birds were thus sensitive to their local perceived threat of predation and traded-off safety from predation （by refuging） and foraging gains in open habitat in a graded, threat-sensitive manner [Current Zoology 60 （6）： 719-728, 2014].

关键词： Foraging Predation risk Threat sensitivity Risk taking Distance-to-refuge Birds

Zircon U-Pb and Lu-Hf isotope constraints on Archean crustal evolution in Southeastern Guyana Shield

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Geoscience Frontiers 2019年第4期10卷 1477-1506页

作者： Joao marinho milhomem Neto jean-michel Lafon Programa de Pos-graduacao em Geologia e Geoquimica-PPGG Instituto de Geociencias-IGUniversidade Federal do Para-UFPA66075-110BelemParaBrazil Laboratório de Geologia Isotópica-Pará-Iso IG-UFPA66075-110BelémParáBrazil

The southeastern Guyana Shield,northeast Amazonian Craton,in the north of Brazil,is part of a widespread orogenic belt developed during the Transamazonian orogenic cycle(2.26-1.95 Ga)that includes a large Archean continental landmass strongly reworked during the Transamazonian orogeny,named Amapa *** consists mainly of a high-grade metamorphic granulitic-migmatitic-gneiss complex,of meso-to Neoarchean age and Rhyacian granitoids and supracrustal *** the first time,coupled U-Pb and Lu-Hf isotope data were obtained on zircon by LA-ICP-mS from five tectono-stratigraphic units of the Archean basement and one Paleoproterozoic intrusive rock,in order to investigate the main episodes of crustal growth and ***-rock Sm-Nd isotope data were compared to the zircon Lu-Hf *** main magmatic episodes were defined by U-Pb zircon dating,two in the mesoarchean(~3.19 Ga and 2.85 Ga)and one in the Neoarchean(~2.69-2.65 Ga).SubchondriticεHf(t)values obtained for almost all investigated units indicate that crustal reworking processes were predominant during the formation of rocks that today make up the Amapa ***-TDmC model ages,ranging from2.99 Ga to 3.97 Ga,indicate that at least two important periods of mantle extraction and continental crust formation occurred during the Archean in southeastern Guyana Shield,an older one in the Eoarchean(~4.0 Ga)and a younger one in the mesoarchean(~3.0-3.1 Ga).The latter is recognized as an important period of crustal accretion *** recognition of an Eoarchean episode to the southeastern most part of the Guyana Shield is unprecedented and was not recorded by whole-rock Sm-Nd data,which were restricted to the meso-Paleoarchean(2.83 Ga to 3.51 Ga).This finding reveals t hat continental crust generation in the Amazonian Craton began at least 500 ma earlier than previously suggested by the SmNd systematics.

关键词： U-Pb-Lu-Hf isotopes Zircon Archean crustal evolution Southeastern Guyana Shield Amazonian Craton

NiWO4 powders prepared via polymeric precursor method for application as ceramic luminescent pigments

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Journal of Advanced Ceramics 2020年第1期9卷 55-63页

作者： Naiara A.LImA Lorena D.S.ALENCAR máximo SIU-LI Carlos A.C.FEITOSA Alexandre mESQUITA jean-Claude m’PEKO maria I.B.BERNARDI Instituto de Física de Sao Carlos Universidade de Sao Paulo13560-970 Sao CarlosSPBrazil Instituto Federal de mato Grosso do Sul IFMS79200-000 AquidauanaMSBrazil Departamento de Física Centro de Ciências Exatas e TecnologiaUniversidade Federal do MaranhaoUFMA65080-805Sao LuisMABrazil Instituto de Geociências e Ciências Exatas Departamento de FísicaUniversidade Estadual Paulista13506-900Rio ClaroSPBrazil

Ni WO4 was prepared using the polymeric precursor method and studied in terms of physical and chemical properties to verify its stability for industrial applications as *** characterization was accomplished using thermal analyses,X-ray diffraction(XRD),scanning electron microscopy(SEm),photoluminescence(PL)and UV–Vis spectroscopies,colorimetric coordinates,and Raman *** the temperature,successive exothermic reactions were observed and they are related with thermal decomposition of the organic *** stability was reached at^700℃.The material is verified to become completely free of second phase at^800℃.The end Ni WO4 powders showed an intense charge transfer(CT)-related tail centered in the ultraviolet region,resulting in a yellow *** addition,the powders exhibited broad excitation band and broad deep blue–green emission band,which were enhanced with increasing powders’crystallinity.

关键词： nickel tungstate yellow pigment colorimetric coordinate optical property structural characterization

mechanical strength of soda-lime glass sandblasted by gravitation

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Friction 2015年第1期3卷 65-71页

作者： Fouad ROUmILI Saci BENBAHOUCHE jean-Christophe SANGLEBOEUF Laboratoire de mécanique de Précision Appliquée Institut d’Optique et Mécanique de PrécisionUniversitéFerhat AbbasSétif19000Algérie Institut de Physique de Rennes UMR CNRS 6251 Bât.10BCampus de Beaulieu35042 Rennes cedexFrance

Damage to a glass surface by sandblasting has a remarkable effect on its mechanical properties and *** this study,we analyze the superficial deterioration of soda-lime glass and its influence on the mechanical *** by gravitation from a fixed height causes damages by the free fall of different quantities of sand,which we performed for a selected grain size and at different angles of *** characterize the surface state,we used different roughness measures(the arithmetic mean value of the roughness Ra,the root mean square roughness Rq,and the maximum roughness Rmax)and measured the optical transmission(transmittance)at different points on the specimen surface using a *** determine the mechanical strength,we proceeded by two methods:first,by a shock ball(falling ball),and then by biaxial bending using circular *** effects of the surface damage on the optical transmission and the mechanical strength of the glass are graphically presented and discussed in this paper.

关键词： sandblasting mechanical strength roughness soda lime glass

A Decision Support Framework for the Choice of Languages and methods for the Design of Real Time Embedded Systems

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Journal of Software Engineering and Applications 2016年第7期9卷 353-397页

作者： Valéry m. monthe Laurent Nana Georges E. Kouamou Claude Tangha Department of Computer Science University of Yaounde 1 Yaounde Cameroon Lab-STICC (UmR CNRS 6285) Department of Computer Science University of Brest Brest France Department of Computer Engineering National Advanced School of Engineering Yaounde Cameroon

The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems is to build a method, or to choose one among those existing, capable to cover the life cycle of a project, and particularly the development phases. This article contributes to answer the question, by proposing an approach based on a multi-criteria comparative study, of few languages and methods dedicated to the design of real time and embedded systems. The underlying objective of this work is to present to designers a wide range of approaches, and elements that can guide their choices. In order to reach this goal, we propose different comparison criteria. Each criterion is divided into sub-criteria, so that the designers can refine their choices according to the qualities they prefer and wish to have in the method or language. We also define a rating scale which is used to assess the retained languages and methods. The scores obtained from this assessment are presented in tables, one table per criterion, followed by a summ.ry table giving the overall scores. Graphics built from these tables are provided and intend to facilitate the judgement and thus the choice of the designers.

关键词： Design method modelling Language Real-Time System Embedded System Comparison Criteria

Intralesional steroid is beneficial in benign refractory esophageal strictures:A meta-analysis

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World Journal of Gastroenterology 2018年第21期24卷 2311-2319页

作者： László Szapáry Benedek Tinusz Nelli Farkas Katalin márta Lajos Szakó Agnes meczker Roland Hágendorn Judit Bajor Aron Vincze Zoltan Gyongyi Alexandra mikó Dezso Csupor Péter Hegyi Balint Eross Institute for Translational medicine Medical SchoolUniversity of PécsPécs 7624Hungary Institute of Bioanalysis Medical SchoolUniversity of PécsPécs 7624Hungary Department of Gastroenterology First Department of MedicineMedical SchoolUniversity of PécsPécs 7624Hungary Department of Public Health medicine Medical SchoolUniversity of PécsPécs 7624Hungary Department of Pharmacognosy Faculty of PharmacyUniversity of SzegedSzeged 6720Hungary

AIm To analyze the effect of intralesional steroid injections in addition to endoscopic dilation of benign refractory esophageal *** A comprehensive search was performed in three databases from inception to 10 April 2017 to identify trials, comparing the efficacy of endoscopic dilation to dilation combined with intralesional steroid injections. Following the data extraction, meta-analytical calculations were performed on measures of outcome by the randomeffects method of Der Simonian and Laird. Heterogeneity of the studies was tested by Cochrane's Q and I^2 statistics. Risk of quality and bias was assessed by the Newcastle Ottawa Scale and JADAD assessment *** Eleven articles were identified suitable for analyses, involving 343 patients, 235 cases and 229 controls in total. Four studies used crossover design with 121 subjects enrolled. The periodic dilation index(PDI) was comparable in 4 studies, where the pooled result showed a significant improvement of PDI in the steroid group(mD:-1.12 dilation/month, 95% CI:-1.99 to -0.25 P = 0.012; I^2 = 74.4%). The total number of repeat dilations(TNRD) was comparable in 5 studies and showed a non-significant decrease(mD:-1.17, 95%CI:-0.24-0.05, P = 0.057; I^2 = 0), while the dysphagia score(DS) was comparable in 5 studies and did not improve(SmD: 0.35, 95%CI:-0.38, 1.08, P = 0.351; I^2 = 83.98%) after intralesional steroid *** Intralesional steroid injection increases the time between endoscopic dilations of benign refractory esophageal strictures. However, its potential role needs further research.

关键词： Intralesional steroid meta-analysis Benign refractory esophageal stricture Dilation

Rational and Continuous measurement of Emotional-Fingerprint, Emotional-Quotient and Categorical vs Proportional Recognition of Facial Emotions with m.A.R.I.E., Second Half

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