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Linking gold mineralization to regional-scale drivers of mineral systems using in situ U-Pb geochronology and pyrite LA-ICP-MS element mapping

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Geoscience Frontiers 2019年第1期10卷 89-105页

作者： Imogen O.H.Fielding Simon P.Johnson Sebastien Meffre Jianwei Zi Stephen Sheppard ross r.large Birger rasmusseng Department of Applied Geology Curtin University Geological Survey of Western Australia CODES ArC Centre of Excellence in Ore Deposits University of Tasmania State Key Lab of Geological Processes and Mineral resources China University of GeosciencesWuhan John de Laeter Centre Curtin University Calidus resources Ltd School of Earth Sciences The University of Western Australia

Proterozoic orogens commonly host a range of hydrothermal ores that form in diverse tectonic settings at different times. However, the link between mineralization and the regional-scale tectonothermal evolution of orogens is usually not well understood, especially in areas subject to multiple hydrothermal ***-scale drivers for mineral systems vary between the different classes of hydrothermal ore, but all involve an energy source and a fluid pathway to focus mineralizing fluids into the upper crust. The Mount Olympus gold deposit in the Proterozoic Capricorn Orogen of Western Australia, was regarded as an orogenic gold deposit that formed at ca. 1738 Ma during the assembly of Proterozoic Australia. However,the trace element chemistry of the pyrite crystals closely resembles those of the Carlin deposits of Nevada,with rims that display solid solution gold accompanied by elevated As, Cu, Sb, Hg, and Tl, surrounding gold-poor cores. New SHrIMP UeP b dating of xenotime intergrown with auriferous pyrite and ore-stage alteration minerals provided a weighted mean^(207) Pb*/^(206) Pb* date of 1769 ± 5 Ma, interpreted as the age of gold mineralization. This was followed by two discrete episodes of hydrothermal alteration at 1727 ± 7 Ma and 1673 ± 8 Ma. The three ages are linked to multiple reactivation of the crustal-scale Nanjilgardy Fault during repeated episodes of intracratonic reworking. The regional-scale drivers for Carlin-like gold mineralization at Mount Olympus are related to a change in tectonic regime during the final stages of the intracratonic 1820 -1770 Ma Capricorn Orogeny. Our results suggest that substantial sized Carlin-like gold deposits can form in an intracratonic setting during regional-scale crustal reworking.

关键词： Geochronology Xenotime SHrIMP LA-ICP-MS Gold mineralization Capricorn orogen

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True polar wander in the Earth system

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Science China Earth Sciences 2023年第6期66卷 1165-1184页

作者： Chong WANG ross N.MITCHELL State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

True polar wander(TPW),or planetary reorientation,is the rotation of solid Earth(crust and mantle)about the liquid outer core in order to stabilize Earth’s rotation due to mass *** TPW is well-documented on Earth presently with satellites and for multiple planets and moons in the Solar System,the prevalence of TPW in Earth history remains *** a history of controversy,both the physical plausibility of TPW on Earth and an empirical basis for it are now *** resistance to the old idea likely stems from the fact that,like plate tectonics,TPW may influence much of the Earth system,thus acknowledging its existence requires rethinking how many different datasets are *** review summarizes the development of TPW as a concept and provides a framework for future research that no longer regards TPW like a ghost process that may or may not exist,but as an integral part of the Earth system that can relate shallow and deep processes that are otherwise only mysteriously ***,we focus on the temporal regularity of large TPW,and discuss its relationship with the supercontinent-megacontinent cycle based on previous *** suggest the assembly of megacontinents has a close linkage to large ***,supercontinent tenure and breakup have a close linkage to fast *** effects of TPW on sea level changes,paleoclimate,biological diversity,and other facets of the Earth system are presented and require interdisciplinary tests in the future.

关键词： True polar wander(TPW) Planetary reorientation Apparent polar wander(APW) Mantle convection Supercontinent cycle Megacontinent

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Achieving Better Educational Practices Through research Evidence:A Critical Analysis and Case Illustration of Benefits and Challenges

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ECNU review of Education 2021年第1期4卷 108-127页

作者： Steven M.ross Jennifer r.Morrison Johns Hopkins University

Purpose:We examine considerations regarding the positive contributions of evidence accountability and challenges that frustrate educators in gaining access to the needed product ***/Approach/Methods:We review the research literature on the multiple characteristics of evidence relative to consumer(practitioner)*** then examine,through a"case illustration"of an initiative in a large school district,a second challenge for evidence usage-conducting viable studies and interpreting outcomes from comprehensive interventions in complex educational ***:Despite attention being given to rigorous evidence,consumers report preferring peer recommendations and local pilot studies as *** our case illustration,we found that the availability of evidence from comprehensive formative evaluation studies was viewed by stakeholders as positively contributing to program implementation quality and sustainability over ***/Value:We use a real-world"case illustration"of a complex initiative in a large,diverse school district to illustrate how current policies and expectations regarding evidence support for educational programs is filtered through multiple agendas and personal needs of key ***,evaluators acquire nontraditional roles that go beyond routine execution of rigorous *** these factors,we offer recommendations for fostering more meaningful and objective interpretations and usage of evidence by local stakeholders.

关键词： Evidence of effectiveness program evaluation technology integration

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Microstructure and Mechanical Properties of Cold Metal Transfer Welding Similar and Dissimilar Aluminum Alloys

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Acta Metallurgica Sinica(English Letters) 2015年第6期28卷 715-724页

作者： Ahmed Elrefaey Nigel G.ross LKr Leichtmetallkompetenzzentrum ranshofen GmbH Austrian Institute of Technology

Integrating structures made from aluminum alloys in automotive industry requires a large amount of joining. As a consequence, the properties of the joints have a significant influence on the overall performance of the whole structure. robot cold metal transfer welding is a relatively new joining technique and has been used in this work to join 6082-T4 and 5182-O aluminum alloy sheets by using Er5356 and Er4043 filler metals. Microstructure characterization was performed by optical microscopy and energy dispersive X-ray spectroscopy, and the mechanical properties were measured by tensile and hardness tests. A correlation is made between welding variables, mechanical properties and the microstructure of welded joints. results indicate that robot cold metal transfer welding provides good joint efficiency with high welding speed, good tensile strength, and ductility. Owing to the low heat input of robot cold metal transfer welding process, the heat affected zone microstructure was quite similar to base metals, and weld metal microstructure was the controlling factor of joint efficiency. The best performing were the 5182/5182 joints welded with Er5356 and these had mechanical property coefficients of 100%, 98%, and 85% for yield strength, ultimate tensile strength, and elongation, respectively.

关键词： Aluminum CMT Welding Microstructure Tensile property

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CUBATUrES FOr MEDIUM-SIZED PLUS ENErGY BUILDINGS

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Journal of Green Building 2017年第2期12卷 28-37页

作者： Friedrich Sick Lioba ross HTW Berlin University of Applied Sciences Wilhelminenhofstr.75AD-12459 BerlinGermany tahl+Weiß Basler Str.55D-79100 FreiburgGermanyphone+***

INTrODUCTION On the basis of dynamic building simulations within a maximal realistic framework,it may be useful with respect to the overall energy balance to dispense with pursuing a minimal surface/volume ratio of buildings-thus minimizing heat losses across the building shell-in favor of solar energy *** specific use of the building(here:office or residential)plays a crucial *** the energy demand for heating and cooling and a possible photovoltaic yield,a surplus is possible in all cases under ***,low unobstructed buildings perform best due to large portions of roof area suitable for solar energy *** tall buildings with less roof area,parts of the facades may be used for solar applications which makes them also perform better than compact *** the total energy demand including auxiliary energy for HVAC and especially electricity for the office and residential usages,respectively,is considered,compact cubatures of the size considered here(about 3500 m^(2))are not capable of providing positive energy *** usage performs worse than office *** are performed for the climatic conditions of Berlin,Germany.

关键词： building surfaces power generation potential building shape and energy demand photovoltaic facades solar energy dynamic building simulations

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A field study of a roof bolter canopy air curtain(2nd generation)for respirable coal mine dust control

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International Journal of Mining Science and Technology 2019年第5期29卷 711-720页

作者： W.r.reed S.Klima M.Shahan G.J.H.ross K.Singh r.Cross T.Grounds CDC NIOSH Pittsburgh Mining Research DivisionPittsburghPA 15236USA Fletcher&Co. HuntingtonWV 25705USA Prairie State Generating Company LLC Lively GroveIL 62257USA

A 2nd generation roof bolter canopy air curtain(CAC)design was tested by National Institute for Occupational Safety and Health(NIOSH)at a Midwestern underground coal *** the study,the roof bolter never operated downwind of the continuous *** a combination of personal Data rams(pDr)and gravimetric samplers,the dust control efficiency of the roof bolter CAC was *** evaluation was determined using three methods:(1)comparing roof bolter operator concentrations underneath the CAC to roof bolter concentrations outside the CAC,(2)comparing roof bolter operator concentrations underneath the CAC to the concentrations at the rear of the bolter,and finally,(3)using the gravimetric data directly underneath the CAC to correct roof bolter operator concentrations underneath the CAC and comparing them to the concentrations at the rear of the *** 1 dust control efficiencies ranged from 53.9%to 60.4%.Method 2 efficiencies ranged from 150.5%to 52.2%,and Method 3 efficiencies ranged from 40.7%to 91%.reasons for negative and low dust control efficiencies are provided in this paper and include:incorrect sampling locations,large distance between CAC and operator,and contamination of intake air from line *** dust concentrations encountered during the testing made it difficult to discern whether differences in concentrations were due to the CAC or due to variances inherent in experimental dust ***,the analyses,especially the Method 3 analysis,show that the CAC can be an effective dust control device.

关键词： Coal roof bolter respirable dust Underground mining

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China's role in Global Climate Change Mitigation

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China & World Economy 2014年第5期22卷 2-18页

作者： ross Garnaut University of Melbourne Chinese Academy of Social Sciences

China contributed a majority of the growth in global greenhouse gas emissions in the first 11 years of this century The trajectory of emissions has changed radically since then, as China has irrplemented its Cancun 2010 commitment to reduce the 2005 emissions intensity of economic activity by 40-45percent by 2020. The change in trajectory has been reinforced by China＇s new model of economic growth, with its greater emphasis on equity in income distribution, consumption and services. The large-scale deployment of low emissions technology in China is lowering the cost of transition to a low carbon economy all over the world. China ＇ s new emissions trajectory improves the opportunity For the international community to meet the 2℃ climate target. It is essential that the changes in China are brought to account in shaping global mitigation ambition.

关键词： climate change policy energy low carbon economy renewable energy

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Examining the intrinsic foot muscles'capacity to modulate plantar flexor gearing and ankle joint contributions to propulsion in vertical jumping

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Journal of Sport and Health Science 2023年第5期12卷 639-647,F0003页

作者： ross Smith Glen Lichtwark Dominic Farris Luke Kelly School of Human Movement and Nutrition Sciences The University of QueenslandBrisbaneQLD 4072Australia Sport and Health Sciences College of Life and Environmental SciencesThe University of ExeterExeterEX12LUUnited Kingdom

Background:During human locomotion,a sufficiently stiff foot allows the ankle plantar flexors to generate large propulsive *** foot stiffness(e.g.,via a carbon plate)increases the ankle’s external moment arm in relation to the internal moment arm(i.e.,increasing gear ratio),reduces plantar flexor muscles’shortening velocity,and enhances muscle force *** contrast,when activation of the foot’s intrinsic muscles is impaired,there is a reduction in foot and ankle work and metatarsophalangeal joint *** speculated that the reduced capacity to actively control metatarsophalangeal joint stiffness may impair the gearing function of the foot at the ***:We used a tibial nerve block to examine the direct effects of the intrinsic foot muscles on ankle joint kinetics,in vivo medial gastrocnemius’musculotendinous dynamics,and ankle gear ratio on 14 participants during maximal vertical ***:Under the nerve block,the internal ankle plantar flexion moment decreased(p=0.004)alongside a reduction in external moment arm length(p=0.021)and ankle joint gear ratio(p=0.049)when compared to the non-blocked *** medial gastrocnemius muscle-tendon unit and fascicle velocity were not different between conditions,the Achilles tendon was shorter during propulsion in the nerve block condition(pr known role of regulating the energetic function of the foot,our data indicate that the intrinsic foot muscles also act to optimize ankle joint torque production and leverage during the propulsion phase of vertical jumping.

关键词： Ankle biomechanics Ankle gearing Foot biomechanicsTagedEnd

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A visual analytics system for optimizing the performance of large-scale networks in supercomputing systems

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Visual Informatics 2018年第1期2卷 98-110页

作者： Takanori Fujiwara Jianping Kelvin Li Misbah Mubarak Caitlin ross Christopher D.Carothers robert B.ross Kwan-Liu Ma University of California DavisUnited States Argonne National Laboratory United States rensselaer Polytechnic Institute United States

The overall efficiency of an extreme-scale supercomputer.largely relies on the performance of its network *** of the state of the art supercomputers use networks based on the increasingly popular Dragonfly *** is crucial to study the behavior and performance of different parallel applications running on Dragonfly networks in order to make optimal system configurations and design choices,such as job scheduling and routing ***,in order to study these temporal network behavior,we would need a tool to analyze and correlate numerous sets of multivariate time-series data collected from the Dragonfly's multi-level *** paper presents such a tool-a visual analytics system-that uses the Dragonfly network to investigate the temporal behavior and optimize the communication performance of a *** coupled interactive visualization with time-series analysis methods to help reveal hidden patterns in the network behavior with respect to different parallel applications and system *** system also provides multiple coordinated views for connecting behaviors observed at different levels of the network hierarchies,which effectively helps visual analysis *** demonstrate the effectiveness of the system with a set of case *** system and findings can not only help improve the communication performance of supercomputing applications,but also the network performance of next-generation supercomputers.

关键词： Supercomputing Parallel communication network Dragonfly networks Time-series data Performance analysis Visual analytics

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Nutritional epidemiology methods and related statistical challenges and opportunities

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Statistical Theory and related Fields 2018年第1期2卷 2-10页

作者： ross L.Prentice Ying Huang Fred Hutchinson Cancer research Center and University of Washington SeattleWAUSA

The public health importance of nutritional epidemiology research is discussed,along withmethodological challenges to obtaining reliable information on dietary approaches to chronicdisease *** issues in assessing dietary intake need to be addressed toobtain reliable disease association ***-reported dietary data typically incorporatemajor random and systematic *** biomarkers offer potential for more reliable analyses,but biomarkers have been established only for a few dietary variables,and these may be tooexpensive to apply to all participants in large epidemiologic cohorts.A possible way forwardinvolves additional nutritional biomarker development using high-dimensional metabolomicprofiling,using blood and urine specimens,in conjunction withfurther development of statisticalapproaches for accommodating measurement error with failure time response *** the opportunity to contribute greatly to worldwide public health through the development of statistical methods to address these nutritional epidemiology research challenges,asis elaborated in this contribution.

关键词： Chronic disease epidemiology failure time data hazard ratio measurement error metabolomics nutritional biomarker regression calibration

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