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XRF Standardless Comparison of Mining Head and Tail Grades to Screen and Display Ore Processing Recoveries

American Journal of Analytical Chemistry 2016年第11期7卷 785-796页

作者： Nicholas E. Pingitore Jr juan w. clague Daniel Gorski Department of Geological Sciences The University of Texas at El Paso El Paso Texas USA Environmental Engineering & Public Health LLC El Paso Texas USA Texas Mineral Resources Corporation Sierra Blanca Texas USA

Separation of target elements or minerals from their host rock or ore is essential to successful mining operation. The inevitable loss of a portion of the desired material that accompanies each step in the extraction process must be documented to develop the operational protocol. Superposition of the characteristic X-ray fluorescence spectra of head (crushed rock ore particles, pre-processing) and tail (post-processing particles) samples provides a direct visual comparison of relative peak sizes, and thereby the relative concentrations, of elements of interest. If the head and tail peaks are identical, none of the element w.s recovered in the extraction process. At the other extreme if the tail peak “flat lines”, i.e., there is no peak, there w.s 100% recovery of that element. Standardless visual comparison is valid if the same mass of identical starting material is incorporated into the head and tail sample analysis pucks, and XRF analytical conditions are identical. The considerable time and expense of acquiring and calibrating the standards associated w.th XRF analysis of 75 or more elements are avoided, a significant advantage during initial broad screening of an experimental extraction procedure. Full quantitation by XRF or an alternate technique can proceed at a later project stage, if desired. The approach retains and presents all features of the original data, thus eliminating questions about data quality, standards and their calibration, and data manipulation in processing from raw.counts to concentrations in printout tables. This form of display is ideal for both the mining professional and such less technical groups as corporate staff, investors, regulators, and the public. Examples presented herein are for heap leaching;the protocol can be applied as w.ll to any of the other traditional ore processing and beneficiation procedures, e.g., gravity concentration, magnetic and electrical separation, froth flotation, and ore sorting.

关键词： XRF (X-Ray Fluorescence) Ore Processing Heap Leach Standardless Analysis Round Top Mountain Rare Earth Elements

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Remarkably Consistent Rare Earth Element Grades at Round Top Yttrofluorite Deposit

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Advances in Materials Physics and Chemistry 2018年第1期8卷 1-14页

作者： Nicholas E. Pingitore Jr. juan w. clague Daniel Gorski Department of Geological Sciences The University of Texas at El Paso El Paso TX USA Environmental Engineering & Public Health LLC El Paso TX USA Texas Mineral Resources Corporation Sierra Blanca TX USA

The peraluminous rhyolite that forms Round Top Mountain (approximately 375 m high × nearly 2 km in diameter), near Sierra Blanca, Hudspeth County, w.st Texas, USA, is enriched in yttrium and heavy rare earth elements (YHREEs), as w.ll as Li, Be, U, Th, Sn, F, Rb, Cs, Nb, and Ta. Texas Mineral Resources Corp. (USA) proposes to release the YHREEs from their unique yttrofluorite host via heap leaching w.th dilute sulfuric acid. The inexpensive process also releases portions of valuable byproduct Be, Li, and U from accessory minerals amid the insoluble feldspars and quartz that comprise 90% - 95% of the surface-exposed rhyolite mountain. The objective of this study is to determine the consistency of mineralization grade, an important consideration in mine planning and preliminary economic analysis. The method is to plot elemental analyses of Y, Dy, Ho, Tm, Yb, Ce, Pr, Nd, Eu, Gd, Tb, U, and Nb from more than 1400 reverse circulation cuttings taken from 64 exploration drill holes against sample depth. The result of inspection of the plots reveals a remarkably homogeneous distribution of minor and trace elements throughout the sampled portion of the massive, 1.6-billion-tonne laccolith. The plots drive the conclusion that Round Top mine feedstock should remain constant for the life of the mine (multiple decades). Thus mining mechanics could be optimized at the start of operations and not require expensive later changes. The physical and chemical design of the heap leach and recovery and purification of target elements from pregnant leach solution also could be perfected during early development.

关键词： Heavy Rare Earth Elements Deposit Grade Round Top Mountain Heap Leach Mineral Processing

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Climate change drives flooding risk increases in the Yellow.River Basin

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Geography and Sustainability 2024年第2期5卷 193-199页

作者： Hengxing Lan Zheng Zhao Langping Li Junhua Li Bojie Fu Naiman Tian Ruixun Lai Sha Zhou Yanbo Zhu Fanyu Zhang Jianbing Peng John J.clague State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China School of Geological Engineering and Geomatics Chang’an UniversityXi’an 710064China University of Chinese Academy of Sciences Beijing 10049China Yellow.River Institute of Hydraulic Research Yellow River Conservancy CommissionZhengzhou 450003China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China State Key Laboratory of Earth Surface Processes and Resources Ecology Beijing Normal UniversityBeijing 100875China Key Laboratory of Mechanics on Disaster and Environment in w.stern China The Ministry of Education of ChinaSchool of Civil Engineering and MechanicsLanzhou UniversityLanzhou 730000China Department of Earth Sciences Simon Fraser UniversityBurnabyCanada

The Yellow.River Basin(YRB)has experienced severe floods and continuous riverbed elevation throughout *** climate change has been suggested to be driving a w.rldw.de increase in flooding ***,ow.ng to insufficient evidence,the quantitative correlation betw.en flooding and climate change remains *** present a long time series of maximum flood discharge in the YRB dating back to 1843 compiled from historical documents and instrument *** in yearly maximum flood discharge show.distinct periods:a dramatic decreasing period from 1843 to 1950,and an oscillating gentle decreasing from 1950 to 2021,w.th the latter period also show.ng increasing more extreme floods.A Mann-Kendall test analysis suggests that the latter period can be further split into tw. distinct sub-periods:an oscillating gentle decreasing period from 1950 to 2000,and a clear recent increasing period from 2000 to *** further predict that climate change w.ll cause an ongoing remarkable increase in future flooding risk and an∼44.4 billion US dollars loss of floods in the YRB in 2100.

关键词： Flooding risk Risk management Climate change Flood discharge Extreme precipitation

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Round Top Mountain rhyolite(Texas, USA), a massive, unique Y-bearing-fluorite-hosted heavy rare earth element(HREE) deposit

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Journal of Rare Earths 2014年第1期32卷 90-96页

作者： PINGITORE Nicholas clague juan GORSKI Daniel Department of Geological Sciences The University of Texas at El Paso Texas Rare Earth Resources

Round Top Mountain in Hudspeth County, w.st Texas, USA is a surface-exposed rhyolite intrusion enriched in Y and heavy rare earth elements （HREEs）, as w.ll as Nb, Ta, Be, Li, F, Sn, Rb, Th, and U. The massive tonnage, estimated at w.ll over 1 billion tons, of the deposit makes it a target for recovery of valuable yttrium and HREEs （YHREEs）, and possibly other scarce ele-ments. Because of the extremely fine grain size of the mineralized rhyolite matrix, it has not been clear w.ich minerals host the YHREEs and in w.at proportions. REE-bearing minerals reported in the deposit included bastn？site-Ce, Y-bearing fluorite, xeno-time-Y, zircon, aeschynite-Ce, a Ca-Th-Pb fluoride, and possibly ancylite-La and cerianite-Ce. Extended X-ray absorption fine struc-ture （EXAFS） indicated that virtually all of the yttrium, a proxy for the HREEs, resided in a coordination in the fluorite-type crystal structure, rather than those in the structures of bastn？site-Ce and xenotime-Y. The YREE grade of the Round Top deposit w.s just over 0.05%, w.th 72%of this consisting of YHREEs. This grade w.s in the range of the South China ionic clay deposits that supply essentially all of the w.rld’s YHREEs. Because the host Y-bearing fluorite is soluble in dilute sulfuric acid at room temperature, a heap leaching of the deposit appeared feasible, aided by the fact that 90%-95%of the rock consists of unreactive and insoluble feld-spars and quartz. The absence of overburden, remarkable consistency of mineralization grade throughout the massive rhyolite, prox-imity （a few.km） to a US interstate highw.y, major rail systems and gas and electricity, temperate climate, and stable political location in the w.rld’s largest economy all enhanced the potential economic appeal of Round Top.

关键词： heavy rare earth elements yttrium-beating fluorite yttrofluorite heap leaching rhyolite Round Top deposit

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Importance of Quaternary research to society

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Episodes 2008年第2期31卷 203-206页

作者： John J. clague Cenlre for Natural Hazard Research Simon Fraser University Burnaby BC Canada V5A 1S6

The Quaternary Period, although only an instant in the 4.5 billion year expanse of geologic time, is disproportionately important because it is the interval during w.ich humans evolved and because it includes the present. Events of the Quaternary are preserved in sediments, ice sheets, and landforms w.th a greater degree of completeness and temporal resolution than those of any earlier period of comparable length. Studies of these historical and environmental archives continue to provide the essential context that allow. scientists to evaluate w.at is happening w.th Earth＇s climate today and to clarify our vulnerability to hazardous natural processes, for example earthquakes, tsunami, volcanic eruptions, floods, and landslides.

关键词：地质学科学研究第四纪地质年代

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Spatial variability of soil w.ter erosion:Comparing empirical and intelligent techniques

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Geoscience Frontiers 2023年第1期14卷 1-16页

作者： Ali Golkarian Khabat Khosravi Mahdi Panahi John J.clague Department of w.tershed Management Engineering Ferdowsi University of MashhadMashhadIran Department of Earth and Environment Florida International UniversityMiamiUSA Division of Smart Regional Innovation Kangwon National UniversityGangwon-do 24341Republic of Korea Department of Earth Sciences Simon Fraser UniversityBurnabyBCCanada

Soil w.ter erosion(Sw.)is an important global hazard that affects food availability through soil degradation,a reduction in crop yield,and agricultural land abandonment.A map of soil erosion susceptibility is a first and vital step in land management and soil *** machine learning(ML)algorithms optimized using the Grey w.lf Optimizer(Gw.)metaheuristic algorithm can be used to accurately map Sw. *** optimized algorithms include Convolutional Neural Netw.rks(CNN and CNN-Gw.),Support Vector Machine(SVM and SVM-Gw.),and Group Method of Data Handling(GMDH and GMDH-Gw.).Results obtained using these algorithms can be compared w.th the w.ll-know. Revised Universal Soil Loss Equation(RUSLE)empirical model and Extreme Gradient Boosting(XGBoost)ML tree-based *** apply these methods together w.th the frequency ratio(FR)model and the Information Gain Ratio(IGR)to determine the relationship betw.en historical Sw. data and controlling geo-environmental factors at 116 sites in the Noor-Rood w.tershed in northern *** Sw. geo-environmental factors are classified in topographical,hydro-climatic,land cover,and geological *** next divided the Sw. sites into tw. datasets,one for model training(70%of the samples=81 locations)and the other for model validation(30%of the samples=35 locations).Finally the model-generated maps w.re evaluated using the Area under the Receiver Operating Characteristic(AU-ROC)*** results show.that elevation and rainfall erosivity have the greatest influence on Sw.,w.ile soil texture and hydrology are less *** CNN-Gw. model(AU-ROC=0.85)outperformed other models,specifically,and in order,SVR-Gw.=GMDH-Gw.(AUC=0.82),CNN=GMDH(AUC=0.81),SVR=XGBoost(AUC=0.80),and *** on the RUSLE model,soil loss in the Noor-Rood w.tershed ranges from 0 to 2644 t ha^(-1)yr^(-1).

关键词： Soil erosion Machine learning RUSLE CNN-Gw. Iran

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Flash flood susceptibility mapping using a novel deep learning model based on deep belief netw.rk,back propagation and genetic algorithm

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Geoscience Frontiers 2021年第3期12卷 146-168页

作者： Himan Shahabi Ataollah Shirzadi Somayeh Ronoud Shahrokh Asadi Binh Thai Pham Fatemeh Mansouripour Marten Geertsema John J.clague Dieu Tien Bui Department of Geomorphology Faculty of Natural ResourcesUniversity of KurdistanSanandaj 66177-15175Iran Board Member of Department of Zrebar Lake Environmental Research Kurdistan Studies InstituteUniversity of KurdistanSanandaj 66177-15175Iran Department of Rangeland and w.tershed Management Faculty of Natural ResourcesUniversity of KurdistanSanandajIran Data Mining Laboratory Department of EngineeringCollege of FarabiUniversity of TehranTehranIran Institute of Research and Development Duy Tan UniversityDa Nang 550000Viet Nam British Columbia Ministry of ForestsLandsNatural Resource Operations and Rural DevelopmentPrince GeorgeBC V2L 1R5Canada Department of Earth Sciences Simon Fraser UniversityBurnabyBC V5A 1S6Canada Geographic Information Science Research Group Ton Duc Thang UniversityHo Chi Minh CityViet Nam Faculty of Environment and Labour Safety Ton Duc Thang UniversityHo Chi Minh CityViet Nam

Flash floods are responsible for loss of life and considerable property damage in many *** susceptibility maps contribute to flood risk reduction in areas that are prone to this hazard if appropriately used by landuse planners and emergency *** main objective of this study is to prepare an accurate flood susceptibility map for the Haraz w.tershed in Iran using a novel modeling approach(DBPGA)based on Deep Belief Netw.rk(DBN)w.th Back Propagation(BP)algorithm optimized by the Genetic Algorithm(GA).For this task,a database comprising ten conditioning factors and 194 flood locations w.s created using the One-R Attribute Evaluation(ORAE)*** w.ll-know. machine learning and optimization algorithms w.re used as benchmarks to compare the prediction accuracy of the proposed *** metrics include sensitivity,specificity accuracy,root mean square error(RMSE),and area under the receiver operatic characteristic curve(AUC)w.re used to assess the validity of the proposed *** result show. that the proposed model has the highest goodness-of-fit(AUC=0.989)and prediction accuracy(AUC=0.985),and based on the validation dataset it outperforms benchmark models including LR(0.885),LMT(0.934),BLR(0.936),ADT(0.976),NBT(0.974),REPTree(0.811),ANFIS-BAT(0.944),ANFIS-CA(0.921),ANFIS-Iw.(0.939),ANFIS-ICA(0.947),and ANFIS-FA(0.917).w. conclude that the DBPGA model is an excellent alternative tool for predicting flash flood susceptibility for other regions prone to flash floods.

关键词： Environmental modeling Flash flood Deep belief netw.rk Over-fitting Iran

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Major clinical and angiographic outcome of drug eluting stents in native ostial coronary artery disease

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w.rld Journal of Cardiovascular Diseases 2013年第3期3卷 320-327页

作者： Khaled R. Abd El Meguid Hesham B. Mahmoud Fouad R. Amin Jonathan R. clague Division of Cardiology Beni-Suef University Hospital Beni-Suef Egypt Division of Cardiology Heatherwood & Wexham Park Hospitals London UK Division of Cardiology Royal Brompton Hospital Imperial College London UK

Objectives: The study w.s designed to evaluate the efficacy and safety of drug eluting stents (DESs) in aorto-ostial (A-O) coronary artery lesions, in terms of early and late restenosis rate;including clinical assessment, non-invasive stress testing and angiographic follow.up. Also, the study w.s aimed to compare the results of implantation of drug eluting stents (DES) to that of bare metal stents (BMS) in aortoostial lesions done over a previous 5 years in Royal Brompton Hospital. Background: The safety and effectiveness of DESs for the treatment of aortoostial lesions. Methods: w. included 161 consecutive patients w.th symptoms subjective of angina pectoris or objective evidence of myocardial ischemia;w.o underw.nt percutaneous coronary interventions (PCI) in coronary ostial lesions using DES. The patients w.re divided into tw. groups based on the site of ostial lesion. The control group consisted of 125 consecutive patients w.o underw.nt percutaneous coronary intervention for ostial lesions using bare metal stents (BMS) implantation in the period immediately before the introduction of DES. The incidence of major adverse cardiac events (MACE), including death or Q-w.ve myocardial infarction (MI), need for repeated revascularization procedure CABG or angioplasty, w.re recorded in-hospital and at tw.lve months ± 3 months. Follow.up angiography w.s only performed in case of recurrent symptoms subjective of myocardial ischemia or if there w.s objective evidence of myocardial ischemia by stress testing. Results: The initial procedure w.s successful in 149 patients (92.5%) in the DES arm. There w.re no statistically significant major in-hospital complications in the DES group, compared to BMS group w.ich show.d 4 cases of in-hospital deaths (p = 0.017). At Tw.lve months ± 3 months follow.up, MACE w.re significantly less frequent in the DES group compared to the BMS group, including death (0.8% vs. 6.4%, p = 0.004) and need for CABG (1.7% vs. 10%, p = 0.012). Conclusions

关键词： Bare Metal Stent DRUG Eluting Stent Ostial Coronary Lesions

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不同步的节段和整体指标预测患者对心脏再同步化治疗反应的比较

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世界核心医学期刊文摘（心脏病学分册） 2007年第3期3卷 55-56页

作者： Duncan A.M. Lim E. clague J. 黄浙勇 Department of Echocardiography Royal Brompton Hospital Imperial College Sydney Street London SW3 6NP United Kingdom

目的:心脏再同步化治疗(CRT)可减少心室内和心室间的不同步,缩短总体等容时间(t-IVT)。本研究比较心室不同步和t-IVT预测CRT临床疗效的程度。方法和结果:评价39例心力衰竭患者在CRT之前和CRT后6个月的心室不同步。

关键词：心脏再同步化指标预测临床疗效射血时间心输出量心脏协会室壁运动充盈时间速度峰值临床反

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俄勒冈海域水合物脊的高分辨率多波束调查

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海洋地质 2016年第4期32卷 18-25页

作者： David A. clague Norm Maher Charles K. Paull 马金凤不详广州海洋地质调查局资料处理研究所

利用新的30kHz的多波束测深系统对俄勒冈边缘的部分水合物脊进行了调查，得到了比该区以往调查更高分辨率的影像。水深数据显示，北脊水深达到588m，南脊水深达到773m。在北脊顶部，大约有26km2的区域回波强度为中一高值，被认为是零散... 详细信息

利用新的30kHz的多波束测深系统对俄勒冈边缘的部分水合物脊进行了调查，得到了比该区以往调查更高分辨率的影像。水深数据显示，北脊水深达到588m，南脊水深达到773m。在北脊顶部，大约有26km2的区域回波强度为中一高值，被认为是零散的、不连续分布的化能合成区、自生碳酸盐岩或者水合物聚集区域。在南脊，相似回波强度的覆盖区域约为4．9km2。然而，在南脊顶部的西侧边缘，确实有一个面积约0．095km2的高强度回波区域，被认为与近乎连续分布的碳酸盐岩和水合物的露头相关。南脊的一个站位位于仅有零星分布的露头区，其早期取样表明为碳酸盐岩和水合物沉积的互层。

关键词：多波束测深系统高分辨率水合物海域回波强度碳酸盐岩连续分布数据显示

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