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Organic Gases in Fluid Inclusions of Ore Minerals and Their Constraints on Ore Genesis:A Case Study of the Changkeng Au-Ag Deposit,Guangdong,China

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Acta Geologica Sinica(English Edition) 2003年第1期77卷 86-94页

作者： DavidI.norman Department of Earth & Environmental Sciences New Mexico Institute of Mining and Technology (NMT) Socorro NM87801 USA

The newly discovered Changkeng Au-Ag deposit is a new type of sediment-hostedprecious metal deposit. Most of the previous researchers believed that the deposit was formed bymeteoric water convection. By using a high vacuum quadrupole gas mass spectrometric system, ninelight hydrocarbons have been recognized in the fluid inclusions in ore minerals collected from theChangkeng deposit. The hydrocarbons are composed mainly of saturated alkanes C_(1-4) and unsaturatedalkenes C_(2-4) and aromatic hydrocarbons, in which the alkanes are predominant, while the contentsof alkenes and aromatic hydrocarbons are very low. The sum alka/sum alke ratio of most samples ishigher than 100, suggesting that those hydrocarbons are mainly generated by pyrolysis of kerogens insedimentary rocks caused by water-rock interactions at medium-low temperatures, and themetallogenic processes might have not been affected by magmatic activity. A thermodynamiccalculation shows that the light hydrocarbons have reached chemical equilibrium at temperatureshigher than 200 deg C, and they may have been generated in the deep part of sedimentary basins(e.g., the Sanzhou basin) and then be transported by ore-forming fluids to a shallow position of thebasin via a long distance. Most of the organic gases are generated by pyrolysis of the type IIkerogens (kukersite) in sedimentary host rocks, only a few by microorganism activity. Thecompositions and various parameters of light hydrocarbons in gold ores are quite similar to those insilver ores, suggesting that the gold and silver ores may have similar metallogenic *** on the compositions of organic gases in fluid inclusions, the authors infer that the Changkengdeposit may be of a tectonic setting of continental rift. The results of this study support fromone aspect the authors' opinion that the Changkeng deposit is not formed by meteoric waterconvection, and that its genesis has a close relationship with the evolution of the Sanzhou basin,so it belon

关键词： ore mineral fluid inclusion organic gas Changkeng Au-Ag deposit

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Towards social behavior in virtual-agent navigation

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Science China(Information Sciences) 2016年第11期59卷 16-32页

作者： Angelos KREMYZAS norman JAKLIN Roland GERAERTS Department of Information and Computing Sciences Utrecht University

we present Social Groups and Navigation(SGN), a method to simulate the walking behavior of small pedestrian groups in virtual environments. SGN is the first method to simulate group behavior on both global and local levels of an underlying planning hierarchy. we define quantitative metrics to measure the coherence and the sociality of a group based on existing empirical data of real crowds. SGN does not explicitly model coherent and social formations, but it lets such formations emerge from simple geometric rules. In addition to a previous version, SGN also handles group-splitting to smaller groups throughout navigation as well as social sub-group behavior whenever a group has to temporarily split up to re-establish its coherence. For groups of four, SGN generates between 13% and 53% more socially-friendly behavior than previous methods, measured over the lifetime of a group in the simulation. For groups of three, the gain is between 15% and 31%, and for groups of two, the gain is between 1% and 4%. SGN is designed in a flexible way, and it can be integrated into any crowd-simulation framework that handles global path planning and any path following as separate *** show that SGN enables the simulation of thousands of agents in real time.

关键词： virtual humans social-group behavior autonomous agent navigation crowd simulation

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Semiautomated 3D Root Segmentation and Evaluation Based on X-Ray CT Imagery

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Plant Phenomics 2021年第1期3卷 86-98页

作者： Stefan Gerth Joelle Claußen Anja Eggert Norbert wörlein Michael waininger Thomas wittenberg norman Uhlmann Development Center X-Ray Technology(EZRT) Fraunhofer Institute for Integrated Systems(IIS)Flugplatzstraße 7590768 FürthGermany Biomedical Engineering Department Fraunhofer Institute for Integrated Systems(IIS)Am Wolfsmantel 331191058 ErlangenGermany

*** X-ray tomography(CTX)is a high-end nondestructive approach for the visual assessment of root architecture in ***,in order to evaluate high-resolution CTX data of root architectures,manual segmentation of the depicted root systems from large-scale volume data is currently necessary,which is both time consuming and error *** duration of such a segmentation is of importance,especially for time-resolved growth analysis,where several instances of a plant need to be segmented and ***,in our application,the contrast between soil and root data varies due to different growth stages and watering situations at the time of ***,the root system itself is expanding in length and in the diameter of individual *** semiautomated and robust root system segmentation from CTX data,we propose the RootForce approach,which is an extension of Frangi’s“multi-scale vesselness”method and integrates a 3D local *** allows a precise delineation of roots with diameters down to severalμm in pots with varying ***,RootForce is not limited to the segmentation of small below-ground organs,but is also able to handle storage roots with a diameter larger than 40 *** CTX volume data of full-grown bean plants as well as time-resolved(3D+time)growth studies of cassava plants,RootForce produces similar(and much faster)results compared to manual segmentation of the regarded root ***,RootForce enables the user to obtain traits not possible to be calculated before,such as total root volume(Vroot),total root length(Lroot),root volume over depth,root growth angles(θmin,θmean,andθmax),root surrounding soil density Dsoil,or form fraction *** proposed RootForce tool can provide a higher efficiency for the semiautomatic high-throughput assessment of the root architectures of different types of plants from large-scale ***,for all datasets

关键词： automated handle Root

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Inelastic Cotunneling Current and Shot Noise of an Interacting Quantum Dot with Ferromagnetic Correlations

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Communications in Theoretical Physics 2007年第12期48卷 1099-1106页

作者： norman J.M.Horing Department of Physics and Engineering Physics Stevens Institute of TechnologyHobokenNew Jersey 07030USA

we explore inelastic cotunneling through a strongly Coulomb-blockaded quantum dot attached to twoferromagnetic leads in the weak coupling limit using a generic quantum Langevin equation *** first developa B1och-type equation microscopically to describe the cotunneling-induced spin relaxation dynamics,and then developexplicit analytical expressions for the local magnetization,current,and its *** this basis,we predict a novelzero-bias anomaly of the differential conductance in the absence of a magnetic field for the anti-parallel configuration,and asymmetric peak splitting in a magnetic ***,for the same system with large polarization,we find a negativezero-frequency differential shot noise in the low positive bias-voltage region. All these effects are ascribed to rapidspin-reversal due to underlying spin-flip cotunneling.

关键词： quantum dot spin polarized tunneling cotunneling

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Femtosecond laser irradiation induced heterojunctions between carbon nanofibers and silver nanowires for a flexible strain sensor

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Journal of Materials Science & Technology 2021年第25期84卷 139-146页

作者： Jiayun Feng Yanhong Tian Sumei wang Ming Xiao Zhuang Hui Chunjin Hang walter w.Duley Y.norman Zhou State Key Laboratory of Advanced welding and Joining Harbin Institute of TechnologyHarbin150001China Centre for Advanced Materials Joining University of WaterlooWaterlooOntarioN2L 3G1Canada Laser Micro/Nano-Fabrication Laboratory School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid wastes National Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of GeosciencesBeijing100083China Department of Physics and Astronomy University of WaterlooWaterlooOntarioN2L 3G1Canada

we report the direct joining of carbon nanofibers(CNFs)to silver nanowire(Ag Nws)by controlled irradiation with femtosecond(fs)laser *** separate types of nano-junction dependent on joint geometry,laser fluence and irradiation time are identified in irradiated *** one type of junction,the tip of an Ag Nw is melted and flows to form a bond with an adjacent *** second type of junction occurs without significant heating of the Ag Nw and involves the softening and flow of carbon in the CNF in response to the transfer of plasmonic energy from the Ag Nw into the *** in a T-type joint configuration can be of either kind depending on the relative orientation of the incident optical field and the long axis of the Ag *** simulations were used to explore this effect for different joint geometries and laser *** electrical properties of a heterojunction involving a single Ag Nw-CNF structure have been measured,and it is found that the junction resistance can be reduced by six orders of magnitude after laser ***,we have investigated the properties of a strain sensor based on an Ag Nw-CNF hybrid nanowire network and find that this device can exhibit high *** sensitivity occurs as nano-junctions induced by fs laser irradiation greatly reduces the initial *** laser-based technique for direct nanojoining of CNF and Ag Nws may enable the design of robust nanowire structures for application in a variety of new devices.

关键词： Nanojoining Carbon nanofiber Silver nanowire Femtosecond laser Strain sensor

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Small-scale convection beneath oceans and continents

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Science Bulletin 2011年第13期56卷 1292-1320页

作者： SLEEP norman H. Department of Geophysics Stanford University

Small-scale convection supplies heat flow of ～17 mw m-2 to the base of stable continents where xenolith studies resolve the ***,effects of small-scale convection are difficult to resolve in ocean *** first pass,most seafloor appears to subside to an asymptote compatible with ～40 mw m-2 convective heat *** common regions are tracked by hotspots so uplift associated with ponded mantle material is an attractive *** seafloor in the North and South Atlantic continues to subside with the square root of age as expected from pure *** theory of stagnant-lid convection provides good scaling relationships for heat *** linear viscosity,heat flow is proportional to the underlying "half-space" viscosity to the 1/3 power and the temperature to change viscosity by a factor of e to the 4/3 *** formalism is easily modified to represent convection beneath a lid of highly viscous and buoyant cratonal lithosphere and to represent transient convection beneath thickening oceanic *** mantle with linear,strongly temperature-dependent,and weakly depth-dependent viscosity is compatible with both oceanic and continental *** complicated rheology may allow vigorous small-scale convection under most but not all old ocean *** viable hypotheses require poorly understood global features,including lateral variations of asthenospheric *** studies have the potential to resolve the lithosphere-asthenosphere boundary,including local variations of its depth associated with small-scale convection.

关键词： lithosphere asthenosphere ocean depth-age small-scale convection craton mantle plume

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Artificial Intelligence & Machine Learning in the Earth Sciences

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 48-51页

作者： norman MacLEOD The Natural History Museum Cromwell RoadLondonSW75BDUK School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China

1 Introduction In the same way mathematics is regarded by many mathematicians as the study of patterns in numbers(Hardy,1940),the earth sciences can be thought of usefully as the study of patterns in the physical,chem... 详细信息

关键词： pattern recognition artificial intelligence machine learning backpropagation convolution neural network

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A Nation of Hypochondriacs

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中国翻译 1995年第1期 62-63页

作者： norman Cousins

The main impression growing out oftwelve years on the faculty of a medicalschool is that the No. 1 health problem in theU. S. today, even more than AIDS orcancer, is that Americans don’t know how

关键词： A Nation of Hypochondriacs

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“He Did Not Call Himself an Artist”:Revisiting Ronald Johnson’s Outsider Aesthetic

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Journal of Foreign Languages and Cultures 2019年第1期3卷 30-38页

作者： norman Finkelstein Xavier University

Ronald Johnson’s relationship to outsider art has long been recognized as crucial to our understanding of his *** interviews and other statements,the poet often affirms his connections with the self-taught makers of fantastic,visionary sculptural *** works of such figures as Simon Rodia,le Facteur Cheval,Raymond Isidore,and James Hampton serve as formal and thematic models for the enormous verbal construction that is *** this essay,I argue that although Johnson is by no means an outsider artist-he is a formally schooled,sophisticated late modernist poet-his fascination with these figures betrays a powerful longing to achieve a state of original innocence which he perceives in their work,but which he knows that he cannot *** gates of Eden,as it were,are closed to the *** examining a number of passages in ARK,I determine that the great poem which Johnson composes serves as the gorgeous compensation for the loss of belief that artists such as Rodia and Hampton still *** language as bricolage,in much the same way some of these artists gather the basic material for their work through oddments and cast offs,Johnson transforms his poem into“scrapture”-a text made of scraps that form a scripture leading poet and reader to a state of rapture.

关键词： Ronald Johnson ARK outsider art James Hampton bricolage

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Chemical pre-treatments improve seed germination and seedling growth in Semecarpus kurzii:an ethnomedicinally important plant

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Journal of Forestry Research 2018年第5期29卷 1283-1289页

作者： Ajit Arun waman Pooja Bohra Avinash norman Division of Horticulture and Forestry ICAR-Central Island Agricultural Research Institute

Semecarpus kurzii *** an important ethnomedicinal plant used for curing tumours,inflammation,fever and pain,and is also a source of iso ricinoleic *** the present investigation,effect of chemical pretreatments on germination and seedling growth revealed significant *** pre-treatments could improve germination and treatment with KNO_3 （9.9 mM）was significantly superior（94%） to the untreated control（76%）.Mean daily germination varied among the treatments（0.90–4.14 seeds per day）,when compared with 2.27 seeds per day in *** germination time was significantly reduced from 22.14 days（control） to 16.40 days（19.8 mM KNO_3） and 17.16 days（1.45 mM GA_3）.Treatment with KNO_3（19.8 mM） and GA_3（1.45 and 2.90 mM）significantly reduced the time for 50% *** with higher concentrations of GA_3 and KNO_3 exhibited significantly faster germination initiation（11.0 and 12.0 days,respectively） over the control（17.0 days）.Seedling vigour index was not improved by *** treatments did not improve shoot growth,collar thickness,or number of seedling leaves; however,root growth was significantly improved over *** with GA_3（2.90 mM） promoted leaf elongation but reduced leaf width *** with KNO_3 and GA_3 could be recommended to obtain healthy seedlings for establishing new plantations of this important medicinal plant species.

关键词： Conservation Indian system of medicines Tribal healthcare wild cashew

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