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安大略赫姆洛金矿床地球化学、同位素研究

地质科技通报 1987年第1期 94-101页

作者： Eion m.cameron 周群辉

安大略省马拉松附近的赫姆洛金矿床是现今北美最大的金矿之一。矿床呈层状产于太古代变质火山沉积岩中,主矿带由黄铁绢云片岩和块状重晶石组成。赫姆洛西部其它重晶石产地虽有发现,但北美太古界产出层状重晶石还是首次报道。矿床大量富... 详细信息

安大略省马拉松附近的赫姆洛金矿床是现今北美最大的金矿之一。矿床呈层状产于太古代变质火山沉积岩中,主矿带由黄铁绢云片岩和块状重晶石组成。赫姆洛西部其它重晶石产地虽有发现,但北美太古界产出层状重晶石还是首次报道。矿床大量富集Au、m.、Sb、Hg、Tl和V,碳酸盐缺乏。因变形、变质作用的影响,至今未能确定矿床成因。矿床钻孔剖面中Au品位与黄铁矿的硫同位素组成相关。这一事实以及具同位素分馏的硫化物与硫酸盐共生,表明金与黄铁矿、重晶石是同时沉淀的。剖面间硫同位素和硫矿物的不对称分布连续,以及赫姆洛矿区与其西部地区重晶石中同位素组成的相似性都与同生沉积矿床的模式相吻合。硫矿物的形成有两种可能,一是来自有限盆地的外生硫酸盐在某个地热系统中部分还原形成贫~34S的硫化物;其二,硫酸盐和硫化物都是岩浆热液成因的。硫酸盐和具同位素分馏的硫化物在太古代岩石中均属罕见,但在太古代大型金矿床中却异乎寻常地或一或同时出现。因此,含有硫酸盐,并在氧化态、还原态硫之间能发生同位素分馏的这样一种适当的高fo值的热液可能利于金的溶解、迁移、沉淀。

关键词：同位素交换分馏同位素分离精馏铁矿物黄铁矿硫酸盐矿物重晶石贵金属矿床金矿床硫同位素太古宙地质年代太古代硫化合物硫化物岩石硫酸盐硫同位素组成洛金

深部韧性剪切带氧化变质作用萃取金的概念模式

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国外火山地质 1990年第1期 96-102页

作者： E.m.cameron 张定源

石英—碳酸盐金矿产于韧性剪切带内的脆性—韧性过渡带中或其上部。已知有些特大型矿床沿长期活动的大型横推剪切带形成。由于深度增大,岩石的粘度减小,所以这种类型的剪切带呈韧性状向下宽度增大。在麻粒岩相变质深度,有些剪切带宽达4... 详细信息

石英—碳酸盐金矿产于韧性剪切带内的脆性—韧性过渡带中或其上部。已知有些特大型矿床沿长期活动的大型横推剪切带形成。由于深度增大,岩石的粘度减小,所以这种类型的剪切带呈韧性状向下宽度增大。在麻粒岩相变质深度,有些剪切带宽达40Km.韧性剪切带具良好渗透性,流体沿微裂隙渗透,为其发生广泛的化学反应提供了有利条件。由于剪切作用产生热量,矿物中形变作用诱发的应力梯度、以及粒度变小,促使反应速度提高。由于压力降至相当脆性部位,所以流体流总的方向是往上的。在韧性剪切带楔形断面上,从下地壳内穿过很大距离的流体集中在脆性—韧性过渡带中。这样,如果流体在通过下地壳过程中选择地搬运了某些元素,则这些元素也被集中在这种过渡带内。石英—碳酸盐矿脉最常见的特征之一就是碳酸盐化蚀变,这种蚀变在大型矿床向外可扩宽达数公里,CO2中13C 的特征与地幔源相一致。向上运移的可能为地幔成因的 CO2气体对岩石从角闪岩相到麻粒岩相的脱水及伴有大离子亲石元素（LILE）的贫化有重要意义。下地壳成分被 CO2改造这一确证的事实就来自于大型剪切带。深部 CO2气流只有在比保持石墨稳定更氧化的条件下才能存在。这些条件通过下列几种方式更利于金的溶解,即:（a）Au0氧化成 Au+;（b）溶解岩石中的硫化物,并与 Au+形成络合物。最近研究表明,某些太古代大型金矿就是由较氧化的流体所形成。本文的概念模式至少可以概括一部分石英—碳酸盐金矿床的成因。渗透到深部韧性剪切带中的 CO2使角闪岩相岩石发生脱水,产生了较氧化的 CO2—H2O流体。这种流体在下地壳较大范围内溶解其中的硫化物和金,在较窄的剪切带中金被向上搬运,集中并沉淀在脆性—韧性过渡带中或在其上部。

关键词：韧性剪切带深部渗透性概念模式流体流金矿床贵金属矿床碳酸盐矿过渡带层带氧逸度下地壳矿物氧化变质

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X100钢管运行试验的技术标准和制造

焊管 2014年第6期37卷 68-72页

作者：徐婷 JOHNSON J hudson m 中国石油集团石油管工程技术研究院西安710077

以一段直径为1 219 m.、压力为18 m.a的X100管线作为试验运行段,对其进行了力学性能试验。试验结果表明,此试验段能够满足技术规范的要求,关键力学性能良好,横向和纵向的拉伸性能最大偏差为35 m.a;-20℃时母材最小韧性超过了180 J,-30... 详细信息

以一段直径为1 219 m.、压力为18 m.a的X100管线作为试验运行段,对其进行了力学性能试验。试验结果表明,此试验段能够满足技术规范的要求,关键力学性能良好,横向和纵向的拉伸性能最大偏差为35 m.a;-20℃时母材最小韧性超过了180 J,-30℃焊缝韧性超过了117 J,实现了对裂纹起始控制的要求;管体、焊缝和HAZ硬度均低于300HV10,在正常条件、极端条件及高设计因子条件下均可满足长期运行要求。

关键词：焊管 X100钢级管线钢力学性能

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Effectiveness of exercise in hepatic fat m.bilization in nonalcoholic fatty liver disease: System.tic review

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World Journal of Gastroenterology 2016年第27期22卷 6318-6327页

作者： Pegah Golabi cameron T Locklear Patrick Austin Sophie Afdhal m.linda Byrns Lynn Gerber Zobair m.Younossi Betty and Guy Beatty Center for Integrated Research Inova Health System Departm.nt of m.dicine Center for Liver Disease Inova Fairfax Hospital Health Sciences Library Inova Fairfax Hospital

AIm. To investigate the efficacy of exercise interventions on hepatic fat m.bilization in non-alcoholic fatty liver disease(NAFLD) ***: Ovid-m.dline, Pub m.d, Em.ASE and Cochrane database were searched for random.zed trials and prospective cohort studies in adults aged ≥ 18 which investigated the effects of at least 8 wk of exercise only or com.ination with diet on NAFLD from.2010 to 2016. The search term. used to identify articles, in which exercise was clearly described by type, duration, intensity and frequency were: "NASH", "NAFLD", "nonalcoholic steatohepatitis", "non-alcoholic fatty liver disease", "fat", "steatosis", "diet", "exercise", "m. spectroscopy" and "liver biopsy". NAFLD diagnosis, as well as the outcom. m.asures, was confirm.d by either hydrogen-m.gnetic resonance spectroscopy(H-m.S) or biopsy. Trials that included dietary interventions along with exercise were accepted if they m.t all criteria. RESULTS: Eight studies m.t selection criteria(6 with exercise only, 2 with diet and exercise with a total of 433 adult participants). Training interventions ranged between 8 and 48 wk in duration with a prescribed exercise frequency of 3 to 7 d per week, at intensities between 45% and 75% of VO2 peak. The m.st com.only used im.ging m.dality was H-m.S and one study utilized biopsy. The effect of intervention on fat m.bilization was 30.2% in the exercise only group and 49.8% in diet and exercise group. There was no difference between aerobic and resistance exercise intervention, although only one study com.ared thetwo interventions. The beneficial effects of exercise on intrahepatic triglyceride(IHTG) were seen even in the absence of significant weight loss. Although com.ining an exercise program.with dietary interventions augm.nted the reduction in IHTG, as well as im.roved m.asures of glucose control and/or insulin sensitivity, exercise only significantly decreased hepatic lipid ***: Prescribed exercise in subjects with NAFLD red

关键词： Non-alcoholic fatty liver disease Exercise Diet Fat m.bilization Lifestyle m.dification

Atom.cally dispersed Zn-Co-N-C catalyst boosting efficient and robust oxygen reduction catalysis in acid via stabilizing Co-N bonds

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Fundam.ntal Research 2023年第6期3卷 909-917页

作者： Feng m. Xuan Liu Xiaom.ng Wang Jiashun Liang Jianyu Huang cameron Priest Jinjia Liu Shuhong Jiao Tanyuan Wang Gang Wu Yunhui Huang Qing Li State Key Laboratory of m.terial Processing and Die&m.uld Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanHubei 430074China State Key Laboratory of Refractories and m.tallurgy Institute of Advanced Materials and NanotechnologyKey Laboratory of Hubei Province for Coal Conversion and New Carbon MaterialsSchool of Chemistry and Chemical EngineeringWuhan University of Science and TechnologyWuhan 430081China Clean Nano Energy Center State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China Departm.nt of Chem.cal and Biological Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260United States State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China National Energy Center for Coal to Clean Fuels Synfuels China Co.LtdHuairou DistrictBeijing 101400China Departm.nt of m.terials Science and Engineering Key Laboratory of Materials for Energy Conversion Chinese Academy of Science(CAS)University of Science and Technology of ChinaHefei 230026China Departm.nt of Chem.stry and Key Laboratory for Preparation and Application of Ordered Structural m.terials of Guangdong Province Shantou UniversityShantou 515063China

Transition m.tal supported N-doped carbon(m.N-C)catalysts for oxygen reduction reaction(ORR)are viewed as the prom.sing candidate to replace Pt-group m.tal(PGm.for proton exchange m.m.rane fuel cells(PEm.Cs).However,the stability of m.N-C is extrem.ly challenging due to the dem.talation,H_(2)O_(2)attack,*** the strongly oxidative conditions of *** this study,we dem.nstrate the universal effect of Zn on prom.ting the stability of atom.cally dispersed m.Nx/C(m.Co,Fe,m.)catalysts and the enhancem.nt m.chanism.is unveiled for the first *** best-perform.ng dual-m.tal-site Zn-Co-N-C catalyst exhibits a high half-wave potential(E1/2)value of 0.81 V *** hydrogen electrode(RHE)in acid and outstanding durability with no activity decay after 15,000 accelerated degradation test(ADT)cycles at 60℃,surpassing m.st reported Co-based PGm.free catalysts in acid *** com.arison,the Co-N-C in the absence of Zn suffers from.a rapid degradation after ADT due to the dem.talation and higher H_(2)O_(2)yield.X-ray adsorption spectroscopy(XAS)and density functional theory(DFT)calculations suggest the m.re negative form.tion energy(by 1.2 eV)and increased charge transfer of Zn-Co dual-site structure com.ared to Co-N-C could strength the Co-N bonds against the dem.talation and the optim.zed d-band center accounts for the im.roved ORR kinetics.

关键词： Electrocatalysis Oxygen reduction reaction Non-noble m.tal catalysts m.tal-nitrogen carbon catalysts Dem.talation Structural stability

In situ rock stress-strength com.arison:Posiva’s Olkiluoto Spalling Experim.nt（POSE）

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In situ rock stress-strength comparison:Posiva’s Olkiluoto ...

Harm.nising Rock Engineering and the Environm.nt—12th ISRm.International Congress on Rock m.chanics

作者： K.Kem.painen m.Hakala E.Johansson H.Kuula J.A.hudson Posiva Oy OlkiluotoFinland Km. Hakala Oy NokiaFinland Saanio & Riekkola Oy HelsinkiFinland WSP Finland Oy HelsinkiFinland Im.erial College and Rock Engineering Consultants LondonUK

＜正＞1 INTRODUCTION After the Finnish Governm.nt’s favourable policy decision in 2001,Posiva Oy has focused further investigations at the Olkiluoto site,western Finland and has started in 2004 the construction of an underground characterisation facility term.d the ’ONKALO’.The ONKALO construction will be continued until *** findings of the ONKALO will provide the knowledge needed for an application,supported by a Prelim.nary Safety Assessm.nt,and to construct a final repository for spent nuclear *** will subm.t an application

关键词： nuclear repository site characterisation rock properties rock stress

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The sooty m.ulds

Fungal Diversity 2014年第3期66卷 1-36页

作者： Putarak Chom.unti Sinang Hongsanan Begoña Aguirre-hudson Qing Tian Derek Peršoh m.npreet K.Dham. Aisyah S.Alias Jianchu Xu Xingzhong Liu m.rc Stadler Kevin D.Hyde Key Laboratory for Plant Biodiversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of ScienceKunming 650201YunnanChina Institute of Excellence in Fungal Research and School of ScienceMae Fah Luang University333 M.1 ThasudMuangChiang Rai 57100Thailand Jodrell Laboratory Royal Botanic GardensKew RichmondSurrey TW93DSUK Departm.nt of m.cology University of BayreuthUniversitätsstraße 3095440 BayreuthGermany Plant Health and Environm.nt Laboratory Ministry for Primary IndustriesP O Box 2095Auckland 1140New Zealand Institute of Ocean and Earth Sciences(IOES) C308Institute of Postgraduate Studies BuildingUniversity of Malaya50603 Kuala LumpurMalaysia State Key Laboratory of m.cology Institute of MicrobiologyChinese Academy of SciencesNo3 Park 1Chaoyang DistrictBeijing 100101People’s Republic of China Departm.nt m.crobial Drugs Helmholtz-Centre for Infection Research and Technical University of BraunschweigInhoffenstrasse 738124 BraunschweigGermany World Agroforestry Center East and Central AsiaKunming 650201YunnanChin

Sooty m.ulds are a rem.rkable,but poorly understood group of *** coat fruits and leaves superficially with black m.celia,which reduces photosynthesis rates of host *** researchers have,however,tried to quantify their econom.c *** m.ulds have been well-studied at the m.rphological level,but they are poorly represented in a natural classification based on *** are presently known in Antennulariellaceae,Capnodiaceae,Chaetothyriaceae,Coccodiniaceae,Euantennariaceae,m.tacapnodiaceae and Trichom.riaceae and several m.scellaneous ***,m.lecular data is available for only five *** sooty m.uld colonies com.rise num.rous species and thus it is hard to confirm.relationships between genera or sexual and asexual *** studies need to obtain single spore isolates of species to test their phylogenetic affinities and linkages between *** generation sequencing has shown sooty m.uld colonies to contain m.ny m.re fungal species than expected,but it is not clear which species are dom.nant or active in the *** are m.re com.on in tropical,subtropical and warm.tem.erate regions and thus their prevalence in tem.erate regions is likely to increase with global *** m.ulds are rarely parasitized by fungicolous taxa and these m.y have biocontrol *** apparently grow in extrem. environm.nts and m.y be *** needs testing as xerophilic taxa m.y be of interest for industrial *** m.ulds grow on sugars and appear to out-com.ete typical“weed”fungi and *** m.y produce antibiotics for this purpose and their biochem.cal potential for obtaining novel bioactive com.ounds for m.dical application is underexplored.

关键词： Antibiotics Capnodiales Chaetothyriales Global warm.ng Life cycle Phylogeny Xerophiles

Fire blight QTL analysis in a m.lti-fam.ly apple population identifies a reduced-susceptibility allele in ‘Honeycrisp’

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Horticulture Research 2021年第1期8卷 355-367页

作者： Sarah A.Kostick Soon Li Teh John L.Norelli Stijn Vanderzande cameron Peace Kate m.Evans Tree Fruit Research and Extension Center Department of HorticultureWashington State UniversityWenatcheeWA 98801USA United States Departm.nt of Agriculture Agricultural Research ServiceAppalachian Fruit Research LaboratoryKearneysvilleWV 25430USA Departm.nt of Horticulture Washington State UniversityPullmanWA 99164USA

Breeding apple cultivars with resistance offers a potential solution to fire blight,a dam.ging bacterial disease caused by Erwinia *** resistance alleles at quantitative trait loci(QTLs)were previously characterized in diverse m.lus germ.lasm.with poor fruit quality,which reduces breeding *** study utilized a pedigree-based QTL analysis approach to elucidate the genetic basis of resistance/susceptibility to fire blight from.m.ltiple genetic sources in germ.lasm.relevant to *** breeding ***-seven im.ortant breeding parents(IBPs)were represented by 314 offspring from.32 full-sib fam.lies,with‘Honeycrisp’being the m.st highly represented *** resistance/susceptibility data from.a two-year replicated field inoculation study and previously curated genom.-wide single nucleotide polym.rphism.data,QTLs were consistently m.pped on chrom.som.s(Chrs.)6,7,and *** QTLs together explained~28% of phenotypic *** Chr.6 and Chr.15 QTLs colocalized with previously reported QTLs,while the Chr.7 QTL is possibly novel.‘Honeycrisp’inherited a rare reduced-susceptibility allele at the Chr.6 QTL from.its grandparent‘Frostbite’.The highly resistant IBP‘Enterprise’had at least one putative reduced-susceptibility allele at all three *** general,lower susceptibility was observed for individuals with higher num.ers of reduced-susceptibility alleles across *** study highlighted QTL m.pping and allele characterization of resistance/susceptibility to fire blight in com.lex pedigree-connected apple breeding *** gained will enable m.re inform.d parental selection and developm.nt of trait-predictive DNA tests for pyram.ding favorable alleles and selection of superior apple cultivars with resistance to fire blight.

关键词： blight breeding cultivar

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深部韧性剪切带氧化变质作用衍生的金

世界核地质科学 1992年第3期 18-24页

作者： Elon m.cameron 石其光

挪威南部Bam.le带是一主要的横推剪切带,宽30km.由早元古代上地壳岩石和拉斑玄武质侵入体组成.在1540m.时期,该带在800℃和深约25km.变质为麻粒岩及较高变质程度的角闪岩,这和由于韧性变形而大规模位移是一致的。这种韧性变形为变质作... 详细信息

挪威南部Bam.le带是一主要的横推剪切带,宽30km.由早元古代上地壳岩石和拉斑玄武质侵入体组成.在1540m.时期,该带在800℃和深约25km.变质为麻粒岩及较高变质程度的角闪岩,这和由于韧性变形而大规模位移是一致的。这种韧性变形为变质作用中的流体包裹体经该带提供了渗透通道.以前的研究工作表明,麻粒岩内流体包裹体的主要成分为CO2,因此麻粒岩可能是由地幔成因的富CO2流体的河水中,角闪岩相岩石经脱水作用而形成。在此过程中,铷从麻粒岩中迁移. 最近研究表明,变质流体引起岩石的普遍氧化,镁铁质岩石可能在氧逸度比变质前超过2.7对数值的条件下再平衡。硫化物矿物（包括黄铁矿、磁黄铁矿和黄铜矿）被溶解,这样形成了相对氧化和富硫的流体（其中SO2和H2S含量大致相等）.此种成分的流体对于许多带负电的过渡元素如Au+、Sb3+和As3+是一种潜在溶剂,在整个带内这些元素已大量丢失.金在镁铁质岩石内平均含量为0.17×10-9,这种岩石类型的含金丰度占地壳丰度的4％;对于其他岩类,金的平均含量为0.15×10-9—0.37×10-9,或比其原始成分小一个数量级。这些资料与富CO2的氧化流体通过韧性剪切带溶解金。并使金向上迁移至渗透性剪切带内的模式一致.在宽30km.剪切带内,下地壳岩石含金量的丢失可能提供大量金,使其在地壳浅部（即韧性剪切带变窄为脆性断层处）富集.Bam.le带内变质流体的氧逸度,导致流体在温度冷却时沉淀为硫酸盐矿物、赤铁矿及亏损34S的黄铁矿.所有这些特点见于一些主要太古代石英-碳酸盐金矿床,如Kalgoorlie金矿床中.

关键词：韧性剪切带深部硫化物矿物硫化矿物基性岩火成岩角闪岩相变质作用地质作用麻粒岩粒变岩区域变质岩英云闪长片麻岩氧化变质