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Structural geometry of orogenic gold deposits： Implications for exploration of world-class and giant deposits

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Geoscience Frontiers 2018年第4期9卷 1163-1177页

作者： David I.Groves M.Santosh Richard j.Goldfarb Liang Zhang Orebusters Pty Ltd Gwelup 6018 Western Australia Australia State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Centre for Tectonics Resources and Exploration Dept. of Earth Sciences University of Adelaide SA 5005 Australia Division of Interdisciplinary Science Faculty of Science Kochi University Kochi 780-8520 Japan

With very few exceptions, orogenic gold deposits formed in subduction-related tectonic settings in accretionary to collisional orogenic belts from Archean to Tertiary times. Their genesis, including metal and fluid source, fluid pathways, depositional mechanisms, and timing relative to regional structural and metamorphic events, continues to be controversial. However, there is now general agreement that these deposits formed from metamorphic fluids, either from metamorphism of intra-basinal rock sequences or de-volatilization of a subducted sediment wedge, during a change from a compressional to transpressional, less commonly transtensional, stress regime, prior to orogenic collapse. In the case of Archean and Paleoproterozoic deposits, the formation of orogenic gold deposits was one of the last events prior to cratonization. The late timing of orogenic gold deposits within the structural evolution of the host orogen implies that any earlier structures may be mineralized and that the current structural geometry of the gold deposits is equivalent to that at the time of their formation provided that there has been no significant post-gold orogenic overprint. Within the host volcano-sedimentary sequences at the province scale, world-class orogenic gold deposits are most commonly located in second-order structures adjacent to crustal scale faults and shear zones, representing the first-order ore-forming fluid pathways, and whose deep lithospheric connection is marked by lamprophyre intrusions which, however, have no direct genetic association with gold deposition. More specifically, the gold deposits are located adjacent to ～10°-25° district-scale jogs in these crustal-scale faults. These jogs are commonly the site of arrays of ～70° cross faults that accommodate the bending of the more rigid components, for example volcanic rocks and intrusive sills, of the host belts. Rotation of blocks between these accommodation faults causes failure of more competent units and/or re

关键词： Structural geometry Tectonic history Fluid pathways Orogenic gold deposits Exploration criteria

An underlying geometrical manifold for Hamiltonian mechanics

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Frontiers of physics 2017年第1期12卷 123-131页

作者： L. P. Horwitz A. Yahalom j. Levitan M. Lewkowicz School of Physics Tel Aviv University Ramat Aviv 69978 Israel Department of Physics Bar llan University Ramat Gan 52900 Israel Department of Physics Ariel University Ariel 40700 Israel Department of Electrical and Electronic Engineering Ariel University Ariel 40700 Israel

We show that there exists an underlying manifold with a conformal metric and compatible connection form, and a metric type Hamiltonian （which we call the geometrical picture）, that can be put into correspondence with the usual Hamilton-Lagrange mechanics. The requirement of dynamical equiva- lence of the two types of Hamiltonians, that the momenta generated by the two pictures be equal for all times, is sufficient to determine an expansion of the conformal factor, defined on the geometrical coordinate representation, in its domain of analyticity with coefficients to all orders determined by functions of the potential of the Hamiltonian-Lagrange picture, defined on the Hamilton-Lagrange coordinate representation, and its derivatives. Conversely, if the conformal function is known, the potential of a Hamilton-Lagrange picture can be determined in a similar way. We show that arbi- trary local variations of the orbits in the Hamilton-Lagrange picture can be generated by variations along geodesics in the geometrical picture and establish a correspondence which provides a basis for understanding how the instability in the geometrical picture is manifested in the instability of the the original Hamiltonian motion.

关键词： geometrical Hamiltonian stability analysis coordinate mapping Riemann-Euclidean Hamiltonian equivalence

Effect of Varying Carbon Content and Shot Peening upon Fatigue Performance of Prealloyed Sintered Steels

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journal of Materials Science & Technology 2009年第5期25卷 607-610页

作者： R.Bidulsky M.Actis-Grande M.Kabtov j.Bidulsk Politecnico Torino Alessandria CampusV.T.Michel5Alessandria 15000Italy Institute of Materials Research SASWatsonova 47Koice04011Slovakia Technical University of Koice Faculty of MetallurgyLetn9Koice 04200Slovakia

The aim of the work was to find out how the modification of surface treatment and microstructures affect the fatigue characteristics of the considered sintered materials. Two different systems were prepared： as-sintered and shot peened prealloyed sintered （Astaloy CrL based） steels with addition of 0.5% and 0.7% C. Sintering was carried out in laboratory tube furnace in an atmosphere of pure gases 75%N2＋25%H2. The sintering temperature was 1180℃ and sintering time was 60 min. Heating and cooling rates were 10℃/min. Fatigue tests were carried out in symmetric plane bending at stress ratio R=-1 with frequency of about 24 Hz. The presented experimental results showed that prealloyed water-atomised steels, with surface modification, exhibit positive effects on the fatigue failure resistance, and for that reason are suitable for high-performance applications.

关键词： Sintered steels Shot peening Fatigue strength S-N curves

Contribution to the Cladonia mycota of Greece,including Cladonia graeca ***

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菌物学报 2011年第6期30卷 877-880页

作者： Harrie j.M.SIPMAN Teuvo AHTI Botanischer Garten & Botanisches Museum Freie Universitaet BerlinKoenigin-Luise-Str.6-8Berlin D-14195Germany Botanical Museum Finnish Museum of Natural HistoryP.O.Box 7FI-00014 University of HelsinkiFinland

From mid-elevation pine forest on the Aegean Sea island of Thasos 8 additional Cladonia species for the lichen mycota of Greece are *** have a wide distribution in Europe and reach their southern limit in *** schistose rock in the same area and on Evvia a new species is described,Cladonia graeca,which is probably related to *** and *** but contains fumarprotocetraric acid instead of psoromic or perlatolic acid.

关键词： TLC 显微镜观察菌物学

Applications of differential algebra for computing Lie algebras of infinitesimal CR-automorphisms

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Science China Mathematics 2014年第9期57卷 1811-1834页

作者： SABZEVARI Masoud HASHEMI Amir M.-ALIZADEH Benyamin MERKER jel Department of Pure Mathematics University of Shahrekord School of Mathematics Institute for Research in Fundamental Sciences (IPM) Department of Mathematical Sciences Isfahan University of Technology School of Mathematics and Computer Sciences Damghan University Dpartment de Mathmatiques d'Orsay Batiment 425Facult des SciencesUniversit Paris XI-Orsay

We perform detailed computations of Lie algebras of infinitesimal CR-automorphisms associated to three specific model real analytic CR-generic submanifolds in C9by employing differential algebra computer tools—mostly within the Maple package DifferentialAlgebra—in order to automate the handling of the arising highly complex linear systems of PDE’*** treating these new examples which prolong previous works of Beloshapka,of Shananina and of Mamai,we provide general formulas for the explicitation of the concerned PDE systems that are valid in arbitrary codimension k 1 and in any CR dimension n ***,we show how Ritt’s reduction algorithm can be adapted to the case under interest,where the concerned PDE systems admit so-called complex conjugations.

关键词： differential algebra differential polynomial ring Ritt reduction algorithm Rosenfeld-Grbner algorithm CR-manifolds Lie algebras of infinitesimal CR-automorphisms

Predicting Nitrogen Status of Rice Using Multispectral Data at Canopy Scale

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Pedosphere 2006年第1期16卷 108-117页

作者： ZHANG jin-Heng WANG Ke j. S. BAILEY WANG Ren-Chao College of Material and Environmental Science Qingdao University of Science and Technology Qingdao 266042（China）. Institute of Agricultural Remote Sensing＆Information System Application Zhejiang University Hangzhou 310029（China） Department of Agriculture and Rural Development for Northern Ireland Agricultural and Environmental Science Division gewforge Lane Belfast BT9 5PX （UK）

Two field experiments were conducted in jiashan and Yuhang towns of Zhejiang Province, China, to study the feasibility of predicting N status of rice using canopy spectral reflectance. The canopy spectral reflectance of rice grown with different levels of N inputs was determined at several important growth stages. Statistical analyses showed that as a result of the different levels of N supply, there were significant differences in the N concentrations of canopy leaves at different growth stages. Since spectral reflectance measurements showed that the N status of rice was related to reflectance in the visible and NIR (near-infrared) ranges, observations for rice in 1 nm bandwidths were then converted to bandwidths in the visible and NIR spectral regions with IKONOS (space imaging) bandwidths and vegetation indices being used to predict the N status of rice. The results indicated that canopy reflectance measurements converted to ratio vegetation index (RVI) and normalized difference vegetation index (NDVI) for simulated IKONOS bands provided a better prediction of rice N status than the reflectance measurements in the simulated IKONOS bands themselves. The precision of the developed regression models using RVI and NDVI proved to be very high with R2 ranging from 0.82 to 0.94, and when validated with experimental data from a different site, the results were satisfactory with R2 ranging from 0.55 to 0.70. Thus, the results showed that theoretically it should be possible to monitor N status using remotely sensed data.

关键词： canopy spectral reflectance, multispectral data, nitrogen status rice vegetation indices

MECHANISM AND KINETICS OF TRANSFORMATION OF ALUMINA INCLUSIONS BY CALCIUM TREATMENT

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 1-8页

作者： Z.j. Han L. Liu M. Lind L. Holappa Central Iron and Steel Research Institute Beijing 100081 China Laboratory of Metallurgy Helsinki University of Technology P.O. Box 6200Espoo 02015 Finland

The basic mechanism and kinetics of the transformation process of alumina inclusions in steel was reported when calcium introduced into the steel by wire feeding orpowder injection. To clarify the mechanisms model, experiments were performed by studying reactions between AltOs and CaO in a laboratory furnace and by performing calcium treatments in an 8kg induction furnace for Al deoxidised melt. The phases formed during the reaction between Al2O3 and CaO were examined by SEM-EDS （scanning electron microscope-energy dispersive spectrometer）, and the reaction sequence of Al2O3=〉 CA6=〉 CA2 =〉 CA =〉 CAx（l） was discussed in term of the experimental observations. The kinetics of the reaction of calcium with alumina inclusions were simulated by immersing alumina plates in a Ca treated steel melt in the induction furnace. Results were compared with observations of real inclusion transformation. A kinetic model was proposed based on the results.

关键词： mechanism kinetics alumina inclusion transformation

Socio-economic factors influencing mopane worm(Imbrasia belina) harvesting in Limpopo Province, South Africa

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journal of Forestry Research 2016年第2期27卷 443-452页

作者： L.j.S.Baiyegunhi B.B.Oppong M.G.Senyolo SAEES-Discipline of Agricultural Economics University of KwaZulu-Natal Department of Crop Sciences Faculty of Science Twshane University of Technology

In South Africa, non-timber forest products, especially mopane worms （Imbrasia belina） have become an important source of food and cash income for rural people living in or near the mopane woodlands. However, the continued harvesting has implications for long term management of the mopane woodlands in the northern parts of South Africa. In order to keep a balance between mopane worm harvesting and biodiversity, an understand- ing of socio-economic factors influencing the harvest at household level is vital to reducing depletion and overex- ploitation of the mopane woodland resources. This study evaluated the socio-economic factors influencing mopane worm harvesting decisions in rural households in Limpopo Province, South Africa using a binary logistic regression model based on a household survey of 120 respondents. Age, gender, education, income from mopane worm sales, social capital （group affiliation）, household size, lack of institution/law to regulate use, distance to the nearest har- vesting site, and regional locations were statistically significant factors influencing household mopane worm harvest decisions. Implications for policy are discussed.

关键词： NTFPs Mopane worm Harvesting Livelihood Conservation South Africa

Anxiety disorders in patients with cardiopulmonary diseases:A brief review

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Sports Medicine and Health Science 2020年第2期2卷 72-79页

作者： Ashley Grace Swavely j.Larry Durstine Cardiac Diagnostic Unit-Clinic 2K Duke Clinic Duke University HospitalDurhamNCUSA Cardiopulmonary Rehabilitation New Hanover Regional Medical CenterWilmingtonNCUSA Department of Exercise Science University of South CarolinaNorman J.Arnold School of Public HealthColumbiaSCUSA

This manuscript reviews the current literature involving clinical anxiety and cardiopulmonary disease,considers the hypothesized physiological mechanisms for anxiety,and discusses the use of exercise as a treatment for both anxiety and cardiopulmonary *** literature summary consists of original investigations,meta-analysis,commentaries,and review publications in order to better understand the biological and psychological mechanisms for using exercise as treatment and to provide details specific to cardiopulmonary disease and anxiety management.A gap in the literature exists concerning the anxiolytic effects of exercise as a psychological and physical treatment in cardiopulmonary *** findings from this review support further investigation into the use of exercise to ameliorate the burden of anxiety in cardiopulmonary disease *** review evaluates the current literature surrounding cardiopulmonary disease and anxiety.A systematic literature search identified articles discussing the prevalence,association,and risk of anxiety in cardiopulmonary *** depression is often studied in this population,recent investigation supports a need for further research regarding anxiety in cardiopulmonary *** to manage patients’psychological profile can reduce exacerbations of known disease,reduce hospital readmission,and improve functional capacity,and overall quality of life.

关键词： Anxiety Cardiopulmonary disease CAD COPD Exercise