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

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

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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

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Theoretical study of defect impact on two-dimensional MoS_2

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Journal of Semiconductors 2015年第12期36卷 18-23页

作者： Anna V.Krivosheeva Victor L.Shaposhnikov Victor e.Borisenko jean-Louis Lazzari Chow Waileong Julia Gusakova Beng Kang Tay Belarusian State University of Informatics and Radioelectronics CNRS Aix-Marseille Université NOVITAS Nanoelectronics Centre of Excellence School of Electrical and Electronic Engineering Nanyang Technological University CINTRA CNRS NTUTHALES Nanyang Technological University

Our theoretical findings demonstrate for the first time a possibility of band-gap engineering of monolayer MoS2 crystals by oxygen and the presence of vacancies. Oxygen atoms are revealed to substitute sulfur ones, forming stable MoS2-xOx ternary compounds, or adsorb on top of the sulfur atoms. The substituting oxygen provides a decrease of the band gap from 1.86 to 1.64 eV and transforms the material from a direct-gap to an indirect-gap semiconductor. The surface adsorbed oxygen atoms decrease the band gap up to 0.98 eV depending on their location tending to the metallic character of the electron energy bands at a high concentration of the adsorbed atoms. Oxygen plasma processing is proposed as an effective technology for such band-gap modifications.

关键词： two-dimensional crystal molybdenum disulfide band gap vacancy oxygen

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Activity enhancement of MgCl2-supported Ziegler-Natta Catalysts by Lewis-acid Pre-treatment for ethylene Polymerization

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Chinese Journal of Polymer Science 2019年第10期37卷 1031-1038,I0006页

作者： Matthieu Humbert Sébastien Norsic jean Raynaud Vincent Monteil UMR 5265 Laboratoire de Chimie Catalyse Polymères et Procédés (C2P2) Université de Lyon

Ziegler-Natta precatalysts were synthetized from Lewis-base-modified-MgCl2 supports and treated by various Lewis acids,prior to activation by triethylaluminum, in order to increase their activity in ethylene polymerization. BCl3 provided the highest increase in activity. Interestingly, polymerization results showed no substantial modification of polymer properties, which is consistent with that Lewis acid only promotes the creation of new active sites, after activation by TeA, possessing very similar features to the original ones achievable with conventional precatalysts(i.e. without Lewis-acid treatment).

关键词： Ziegler-Natta catalysis ethylene polymerization Heterogeneous catalysis Lewis acids

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Update of Meat Standards Australia and the cuts based grading scheme for beef and sheepmeat

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Journal of Integrative Agriculture 2018年第7期17卷 1641-1654页

作者： Sarah P.F.Bonny Rachel A.O'Reilly David W.Pethick Graham e.Gardner jean-Francois Hocquette Liselotte Pannier School of Veterinary and Life Sciences Murdoch UniversityMurdochWA 6150Australia Clermont Université INRAVetAgro SupUMR1213Recherches sur les HerbivoresSaint-Genes Champanelle F-63122France

Changing markets and evolving consumer demand present new challenges for the beef and sheep industries. In response, the industry has been investing in innovations to deliver new products and management systems to consumers. One such innovation is the Meat Standards Australia（MSA） system. This system is a Total Quality Management System, aimed at delivering an eating quality guarantee to consumers, and through this adding value to the entire supply chain. At present, it is well developed for beef and still evolving for sheepmeat. MSA has identified Critical Control Points（CCPs） in the production, pre-slaughter, processing and value-adding aspects of the supply chain that impact on consumer palatability through the large-scale taste testing of meat by untrained consumers. These CCPs are used as either（1） mandatory criteria determining eligibility for grading, and（2） inputs in a model predicting the palatability of individual combinations of muscle and different cooking methods. Through the prediction of palatability, MSA increases consumer satisfaction and is used to provide assurance for branded products and new marketing innovations in Australia and internationally. This has added significant value to the Australian beef industry, with several retail examples demonstrating consumer willingness to pay more for premium quality beef and sheepmeat products based on the MSA grading scores. This price differential at retail allows the value of the carcass to be calculated based on the eating quality as well as the volume produced, thereby delivering a financial reward for farmers producing high quality carcasses. The continuous quality scale of MSA allows producers to realise the financial gain of incremental improvements in quality, as well as the precise economic weights associated with traits such as marbling, ossification score, or breed. The use of MSA in this fashion has underpinned a new and innovative supply chain where the pricing is transparent and allows produ

关键词： eating quality consumer beef sheep Meat Standards Australia international cut

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Lanthanide mechanoluminescence

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Journal of Rare earths 2018年第1期36卷 1-41页

作者： jean-Claude G.Bünzli Ka-Leung Wong Institute of Chemical Sciences and engineering Swiss Federal Institute of Technology Lausanne (EPFL) CH-1015 Lausanne Switzerland Department of Chemistry Hong Kong Baptist University Kowloon Tong Hong Kong China

Mechanoluminescence （ML） is the emission of light consecutive to a mechanical force or stress imposed to a crystalline material. Many inorganic and organic compounds present this phenomenon that is known for over 400 years. Lanthanide and uranyl salts were among the first substances investigated for this property. Mechanoluminescence, also referred to as triboluminescence, is often considered as being a badly understood phenomenon. In fact it is because of two main reasons. Firstly, a variety of different mechanical stresses, from simple rubbing, to applied pressure, crushing, impact of a weight, ultrasound, laser-generated shock wave, crystallization, dissolution of crystals, or even wind can trigger it. Secondly, ML is very sensitive to the purity and morphology of the sample： in inorganic compounds, generation of traps by doping ＂impurities＂（e.g. lanthanide ions） is responsible for light emission so that the exact composition of the sample has to be known to a very detailed level; for chelates, the crystallization conditions are crucial since they often generate extended networks of weak interactions that are instrumental in triggering ML when they are broken. In fact mechanisms of ML are relatively well known and theories and models often reproduce very well the experiments. Additionally, practical applications are at hand, for example stress, crack, and impact sensors based on SrAI204：eu11 or et3NH[eu（dbm）4] are used to test structures and materials as diverse as road bridges, reinforced concrete elements, pressur- ized containers or airplane wings and to image the propagation of cracks or stress distribution. Military and security applications involve detecting the passage of vehicle or soldiers and producing counter- feiting inks while more joyful applications are luminous balls, wrapping papers and adhesive tapes. Not only bulk materials, but micro- and nanoparticles feature mechanoluminescent properties and single particle manipulation under an AFM allows

关键词： MechanoluminescenceRare earthsStress sensorsPressure sensorsImpact sensors

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An efficient Bio-inspired Oxygen Reduction Reaction Catalyst:MnO_(x)Nanosheets Incorporated Iron Phthalocyanine Functionalized Graphene

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能源与环境材料（英文） 2021年第3期4卷 474-480页

作者： Xing Wu Yi Cheng jean-Pierre Veder San Ping Jiang Department of environmental engineering School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083China National engineering Technology Research Center for Control and Treatment of Heavy-metal Pollution Changsha 410083China John de Laeter Centre Curtin UniversityPerth WA 6102Australia Fuels and energy Technology Institute Curtin UniversityPerth WA 6102Australia

Oxygen reduction reaction(ORR)catalysts play a critical role in energy storage and conversion devices and have been attracted enormous interests,and however,it remains challenging to develop highly active cheap catalysts in a simple and green *** by the heme-copper oxidases(HOCs),in which the ORR active center is originated from the incorporation of Fe-N_(4)with copper atom,we here developed a fine manganese oxide nanosheets(MnO_(x)NSs)integrated with iron phthalocyanine(FePc)anchored on highly conductive graphene(MnO_(x)/FePc-G)through a green route only involve ethanol as the *** bio-inspired catalyst MnO_(x)/Fe Pc-G demonstrated high ORR activity with a half-wave potential(e_(1/2))of 0.887 V,about 57 mV more positive than that of Pt/*** the current density(j)at 0.9 V is about 1.9 m A cm^(-2),which is three times of Pt/C and *** importantly,the bio-inspired systems show superior stability in comparison to commercial Pt/C,showing a potential of 0.863 V to deliver a j of 3 mA cm^(-2)after 18000 s polarization,about 80 mV higher than that of 0.783 V for Pt/*** high activity is contributed by the integration of the Fe Pc and MnO_(x)NSs that plays the role to assist the cleavage of the O_(2)*** approach provides a new evidence to develop highly efficient ORR catalysts through imitate the naturally involved systems through a simple route.

关键词： bio-inspired heme-copper oxidases iron phthalocyanine MnO_(x)nanosheets oxygen reduction reaction

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Mobile silencing in plants:what is the signal and what defines the target

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Frontiers in Biology 2011年第2期6卷 140-146页

作者： Dacheng LIANG e.jean FINNeGAN elizebeth S.DeNNIS Peter M.WATeRHOUSe Ming-Bo WANG CSIRO Plant Industry Clunies Ross StreetCanberraACT 2601Australia School of Molecular Bioscience University of SydneySydney NSW 2006Australia

RNA-mediated silencing in plants can spread from cell to cell and over a long distance,and such mobile silencing has been extensively studied in the past ***,major questions remain as to what is the exact nature of the mobile silencing signals,how the components of the RNA-directed DNA methylation pathway are involved,and why systemic spread of silencing has only been observed for transgenes but not endogenous *** this review,we provide an overview of the current knowledge on mobile gene silencing in plants and present a model where systemic silencing involves long nuclear RNA transcripts that serve as a template to amplify primary siRNA signals.

关键词： endogenous template fines

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A review of some methodological developments on full waveform inversion tackled in the SeISCOPe group

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石油物探 2017年第1期56卷 3-19页

作者： Romain BROSSIeR Ludovic MeTIVIeR jean VIRIeUX YANG Pengliang ZHOU Wei Univ.Grenoble Alpes ISTerre Grenoble France Univ. Grenoble Alpes CNRS LJK Grenoble France

Full waveform inversion(FWI)is a data-fitting inverse problem aiming to delineate high-resolution quantitative images of the *** its basic principle has been proposed in the eighties,the approach has been significantly developed and applied to2Dand 3Dproblems at various scales for the last fifteen *** these successes,FWI is still facing some issues for applications in complex geological setups because of some lack of robustness and automatic workflow,while being computationally *** this paper,after a short review of the basic FWI formulation and analysis of the FWI gradient,three recent methodological developments performed in the frame of the SeISCOPe project are ***,an algorithmic development is presented as a low-memory and computationally efficient approach for building the time-domain FWI gradient in 3Dviscous ***,a reformulation of FWI is performed to handle reflections in their tomography regime while still using the diving waves,leading to the joint full waveform inversion(JFWI)***,an optimal transport approach is proposed as an alternative to the classical difference-based misfit for mitigating the cycle-skipping issue.

关键词：全波形反演随机边界异构并行作业池速度反演

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Review of the development and uses of hard grade asphalts in France

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Journal of Road engineering 2021年第1期1卷 73-79页

作者： jean-Francois Corte Directorate of Transport Infrastructures Ministry of TransportLa Defense 92055France

Hard grade paving asphalts,i.e.,having a penetration at 25C lower than 25 mm/10,have experienced,in France,a significant development over the last forty years,linked to the development of high modulus asphalt concrete for rehabilitation then for new construction of road *** the first part,this paper provides a review of the evolution of asphalts in France over the past sixty years towards the use of harder penetration grades and a limitation of the evolution of the asphalt in the mixing plant to avoid early cracking of the *** recommendations in relation to climatic conditions are *** characteristics of different hard asphalts produced in France are presented including data on the effect of ageing tests rolling thin film oven test(RTFOT)and pressure ageing vessel(PAV).Hardening of hard asphalt after RTFOTþPAV is comparable to that of softer *** performance related to low temperature cracking is less which limits the use of plain hard asphalt in pavements subjected to severe winter conditions and requires polymer *** specifications for hard grade paving asphalts based on traditional empirical tests included in the european standard developed in the mid 2000s and the choices made in France are presented.A comparison of the specifications for hard grade paving asphalts in the european standards and of those proposed for China shows that the european specifications are more stringent as regards consistency and evolution after ageing tests.

关键词： Asphalt Hard grade Rheology Standard

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