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Geochemistry, mineral paragenesis and geothermal conditions of oreforming fluids from the Ain El Bey Cu–Fe deposit: potential occurrence of native gold and precious metal traces (North African orogenic belt, Northern Tunisia)

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Acta Geochimica 2024年第2期43卷 366-384页

作者： Rania ben Aissa Wiem ben Aissa said Tlig Lassaad ben Aissa Abdessalem ben Haj Amara Faculty of science of Bizerte University of Carthage7021 ZarzounaBizerteTunisia Laboratoire de Recherche Ressources Materiaux et EcosystemesUniversity of Carthage7021 ZarzounaBizerteTunisia Department of Geology University Claude Bernard Lyon 169622 VilleurbanneFrance Faculty of science of Tunis University of Tunis-El ManarRommana1068 TunisTunisia

The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. scanning Electron Microscope--Energy Dispersive spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(s. such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.

关键词： Ore-formingﬂuids Mineral geochemistry Mineral geothermometers Native silver-gold Ain El Bey Ore deposit North Tunisia

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A multi-objective pigeon inspired optimization algorithm for fuzzy production scheduling problem considering mould maintenance

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science China(Information sciences) 2019年第7期62卷 15-32页

作者： Xiaoyue FU Felix T.s.CHAN ben NIU Nick s.H.CHUNG Ting QU Department of Industrial and systems Engineering The Hong Kong Polytechnic University College of Management Shenzhen University school of Electrical and Information Engineering Jinan University

The fuzzy production scheduling problem considering mould maintenance(FPsP-MM) is studied. The processing time and the maintenance time are represented by triangular fuzzy numbers. When tasks are executed based on the sequence provided by the fuzzy schedule, the real duration of each task needs to be known so the posteriori solution with deterministic processing times can be obtained. Therefore, the concept of the schedule robustness needs to be considered for the fuzzy problem. The robustness is considered as the optimization objective except for the fuzzy makespan in this research. To optimize these two objective functions, a multi-objective pigeon inspired optimization(MOPIO) algorithm is developed. To extend the pigeon inspired optimization(PIO) algorithm from the single-objective case to the multi-objective case, nondominated solutions are used as candidates for the leader pigeon designation and a special crowding distance is used to ensure a good distribution of solutions in both the objective space and the corresponding decision space. Furthermore, an index-based ring topology is used to manage the convergence speed. Numerical experiments on a variety of simulated scenarios show the excellent efficiency and effectiveness of the proposed MOPIO algorithm by comparing it with other algorithms.

关键词： fuzzy production scheduling mould maintenance pigeon inspired optimization multi-objective

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Zircon U-Pb dating and geochemical study of the Xianggou granite in the Ma'anqiao gold deposit and its relationship with gold mineralization

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science China Earth sciences 2010年第2期53卷 220-240页

作者： LEE ben state Key Laboratory of Continental Dynamics Department of GeologyNorthwest University

single zircon LA-ICP-Ms U-Pb dating and lithogeochemical studies have been performed on the Xianggou monzonitic granitic porphyry outcropped in the Ma’anqiao gold deposit.A weighted average U-Pb age of 242.0±0.8 Ma for Xianggou monzonitic porphyry has been *** corresponds with the conclusions of previous studies indicating a syn-orogenic age (242±21 Ma) of the Qinling Orogenic Belt,suggesting that the formation of the Xianggou granite should be associated with the collisional event of the North China Plate and the Yangtze Plate in the Indosinian *** Xianggou granite is characterized by the high silicon and alkali of high K calc-alkaline series *** is rich in Al (Al2O3=14.49%-15.61%) and sr (457.10-630.82 ppm),poor in Y (s high ratios of sr/Y (76.24-97.34) and (La/Yb)N (29.65-46.10),as well as strongly fractionated REE *** geochemical characteristics suggest the Xianggou granite can be classified as C-type adakitic *** initial sr isotope ratios for the Xianggou granite vary from 0.70642 to 0.70668,εNd(t) values from -4.54 to -3.98,and TDM values from 1152 Ma to 1220 *** low εNd(t) and Isr and high TDM values,as well as Na2O/K2O ratios of the Xianggou granite are close to 1 (Na2O/K2O=0.95-1.10),indicating that it is not an I-type adakite formed by partial melting of the subducting oceanic crust,nor adakitic rock formed by melting of the underplated basaltic lower crust,but the product of partial melting of the nonunderplated basaltic thickened lower *** from the Xianggou pluton have a homogeneous Hf isotopic composition with negative εHf(t) values (between -9.7 and -5.9,with an average of -6.9),indicating that the rock-forming materials were mostly extracted from the ancient crust,not from the depleted *** Xianggou monzonitic granitic porphyry is rich in LILE and LREE and depleted in HsFE,HREE and Y;the composition of trace element and REE are similar to those

关键词： zircon U-Pb dating Xianggou monzonitic granitic porphyry Carlin type and Carlin-like type gold deposits petrologenic and metallogenic dynamic background

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spatial point-pattern analysis as a powerful tool in identifying pattern-process relationships in plant ecology: an updated review

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Ecological Processes 2021年第1期10卷 772-794页

作者： Mariem ben-said Applied Biology and Pathology Laboratory Department of BiologyFaculty of SciencesAbdelmalek Essaadi UniversityTetouanMorocco

Background:Ecological processes such as seedling establishment,biotic interactions,and mortality can leave footprints on species spatial structure that can be detectable through spatial point-pattern analysis(sPPA).Being widely used in plant ecology,sPPA is increasingly carried out to describe biotic interactions and interpret patternprocess ***,some aspects are still subjected to a non-negligible debate such as required sample size(in terms of the number of points and plot area),the link between the low number of points and frequently observed random(or independent)patterns,and relating patterns to *** this paper,an overview of sPPA is given based on rich and updated literature providing guidance for ecologists(especially beginners)on summary statistics,uni-/bi-/multivariate analysis,unmarked/marked analysis,types of marks,*** ambiguities in sPPA are also ***:sPPA has a long history in plant ecology and is based on a large set of summary statistics aiming to describe species spatial *** mechanisms known to be responsible for species spatial patterns are actually investigated in different biomes and for different *** processes,plant environmental conditions,and human intervention are interrelated and are key drivers of plant spatial *** spite of being not recommended,small sample sizes are more common in *** some areas,periodic forest inventories and permanent plots are scarce although they are key tools for spatial data availability and plant dynamic ***:The spatial position of plants is an interesting source of information that helps to make hypotheses about processes responsible for plant spatial *** the continuous progress of sPPA,some ambiguities require further clarifications.

关键词： spatial analysis Point-pattern summary statistics second-order characteristics spatial structure species interactions Competition Facilitation Positive association Negative association

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Early Cretaceous Tectonostratigraphic Evolution of the southern Tunisian Margin Based on Gravity,seismic and Potential Field Data:New Insights into a Geodynamic Evolution in a Tethyan and Mesogean Rifting Context

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Journal of Earth science 2023年第3期34卷 879-899页

作者： Mohamed ben Chelbi Faculty of sciences of Tunis Laboratory of GeodynamicGeonumeric and Geomaterials(L3G)LR18ES37University of Tunis El ManarTunisTunisia

Many geophysical and geological data have been used to interpret the tectonic evolution of the south-eastern part of the Tunisian margin and to analyze the dominant structures in the *** Menzel Habib Plain(MHP)and surroundings,targeted by this study,exhibits thick siliciclastic and carbonate formations attributed to the Early Cretaceous *** of seismic and gravimetric data coupled with analysis of the syndepositional faults affecting these formations prove that the Tunisian margin is dominated,during this period,by N-s to NE-sW extensional *** geodynamic evolution of the MHP is mainly due to the irregular normal movement of the N-s faults,which represents the southernmost branch of the N-s Axis(NsA)and of the NW-sE faults,which constitutes the sE segment of the south Atlasic fault corridor(sAFC).In addition,the NE-sW and E-W oriented faults contributed to this *** extensive periods,this network of faults determines horst and grabens basin geometry or tilted blocks inducing formation of several distinct areas with different subsidence ***,the normal activity of the major faults promotes the vertical mobilization of the Triassic salt resulting in the individualization of several diapiric bodies,some of which pierced their sedimentary *** dynamics reflect echoes of the sinistral drifting of Africa with respect to Europe,integrated in a long Tethyan rifting cycle,and the beginning of opening of the Mesogean sea,respectively.

关键词： Tunisian margin Early Cretaceous extensive tectonics Tethyan and Mesogean rifting geodynamics

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solid-state photoinduced luminescence switch and its advanced optical applications

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science China Chemistry 2018年第4期61卷 377-378页

作者： ben Zhong Tang Department of Chemistry The Hong Kong University of Science & Technology

spiropyran（sP）and its derivatives were one of the earliest and most extensive systems in organic photochromic ***,the distinct absorption changes will occur during the structural isomerization from sP to merocyanine... 详细信息

关键词：光开关固态应用衍生物光反应异构化

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PCP-Ed: Parallel coordinate plots for ensemble data

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Visual Informatics 2023年第1期7卷 56-65页

作者： Elif E.Firat ben swallow Robert s.Laramee University of Nottingham UK University of Glasgow UK

The Parallel Coordinate Plot(PCP)is a complex visual design commonly used for the analysis of high-dimensional *** data size and complexity may make it challenging to decipher and uncover trends and outliers in a confined space.A dense PCP image resulting from overlapping edges may cause patterns to be *** develop techniques aimed at exploring the relationship between data dimensions to uncover trends in dense *** introduce correlation glyphs in the PCP view to reveal the strength of the correlation between adjacent axis pairs as well as an interactive glyph lens to uncover links between data dimensions by investigating dense areas of edge *** also present a subtraction operator to identify differences between two similar multivariate data sets and relationship-guided dimensionality reduction by collapsing axis *** finally present a case study of our techniques applied to ensemble data and provide feedback from a domain expert in epidemiology.

关键词： Parallel coordinates Overplotting Ensemble data

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FINDING THE TOPOLOGY OF IMPLICITLY DEFINED TWO ALGEBRAIC PLANE CURVEs

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Journal of systems science & Complexity 2012年第2期25卷 362-374页

作者： ben GAO Yufu CHEN school of Mathematical sciences Graduate University of Chinese Academy of Sciences

An algorithm is given for computing in a very efficient way the topology of two real algebraic plane curves defined *** authors preform a symbolic pre-processing that allows us later to execute all numerical computati... 详细信息

关键词： Algebraic curves cylindrical algebraic decomposition generic position subresultantssequence topology.

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A theoretical framework for improved fire suppression by linking management models with smart early fire detection and suppression technologies

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Journal of Forestry Research 2024年第5期35卷 1-13页

作者： Li Meng Jim O’Hehir Jing Gao stefan Peters Anthony hay University of south Australia AdelaideSAAustralia Esk spatial InvermayTASAustralia

Bushfires are devastating to forest managers,owners,residents,and the natural *** tech-nological advances indicate a potential for faster response times in terms of detecting and suppressing ***,to date,all these technologies have been applied in *** paper introduces the latest fire detection and sup-pression technologies from ground to *** operations research method was used to assemble these technologies into a theoretical framework for fire detection and *** framework harnesses the advantages of satellite-based,drone,sensor,and human reporting technologies as well as image processing and artificial intelligence machine *** study concludes that,if a system is designed to maximise the use of available technologies and carefully adopts them through complementary arrangements,a fire detection and resource suppression system can achieve the ultimate aim:to reduce the risk of fire hazards and the dam-age they may cause.

关键词： Forest fire Resource suppression smart fire detection and suppression system Forest fire management Holistic system

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Nutritional management of newborn infants:Practical guidelines

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World Journal of Gastroenterology 2008年第40期14卷 6133-6139页

作者： Xiao-Ming ben Department ofNeonatology NanjingChildren's Hospital of Nanjing Medical University Nanjing210008 Jiangsu Province China

The requirements of growth and organ development create a challenge in nutritional management of newborn infants,especially premature newborn and intestinal-failure *** their feeding may increase the risk of necrotizing enterocolitis,some high-risk infants receive a small volume of feeding or parenteral nutrition (PN) without enteral *** review summarizes the current research progress in the nutritional management of newborn *** of MEDLINE (1998-2007),Cochrane Central Register of Controlled Trials (The Cochrane Library,Issue 3,2007),abstracts and conference proceedings,references from relevant publications in the English language were performed,showing that breast milk is the preferred source of nutrients for enteral feeding of newborn *** number of nutrients found in human milk was recommended as a guideline in establishing the minimum and maximum levels in infant *** fear of necrotizing enterocolitis and feeding intolerance are the major factors limiting the use of the enteral route as the primary means of nourishing premature *** may help to meet many of the nutritional needs of these infants,but has significant detrimental side *** feedings (small volume of feeding given at the same rate for at least 5 d) during PN are a strategy to enhance the feeding tolerance and decrease the side effects of PN and the time to achieve full *** milk is a key component of any strategy for enteral nutrition of all ***,the amounts of calcium,phosphorus,zinc and other nutrients are inadequate to meet the needs of the very low birth weight (VLBW) infants during ***,safe and effective means to fortify human milk are essential to the care of VLBW infants.

关键词： Breast milk Infant formula Trophic feeding Parenteral nutrition

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