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科迪勒拉北部浸染型金矿床生物地球化学样品中金和砷含量的季节性变化

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黄金科技动态 1990年第7期 12-16页

作者： l.w.ashton 张书成

早在1950年就有关于用生物地球化学方法探查金矿成功先例的报道,认为浸染状金的示踪元素(Au、As、Hg、Sb、Ag、T1)中最主要的是Au和As(已知植物积聚)。科学家在俄勒冈Quartz山热泉型浸染状金矿床上进行了定向测量,提出了在本区勘探金矿... 详细信息

早在1950年就有关于用生物地球化学方法探查金矿成功先例的报道,认为浸染状金的示踪元素(Au、As、Hg、Sb、Ag、T1)中最主要的是Au和As(已知植物积聚)。科学家在俄勒冈Quartz山热泉型浸染状金矿床上进行了定向测量,提出了在本区勘探金矿的三个关键问题:基岩地质与树木及土壤中的痕量元素含量之间的关系;

关键词：金矿生物地救化学方法勘探

美国北科迪勒拉地区某浸染状金矿床生物地球化学样品中Au、As的季节性变化

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国外地质勘探技术 1990年第11期 39-41页

作者： l.w.ashton w.C.Riese 吴荣庆

石英山矿床为热泉型,矿化体产于浅部。矿区位于由一系列走向Nw—N的断块山脉构成的俄勒冈州中南部。分析与采样程序针叶和细枝在80℃温度下干燥一整夜,在隔火炉内于550℃时灰化,用上水煮解、蒸发至初干,最后配制成25ml25%HCl的溶液。其... 详细信息

石英山矿床为热泉型,矿化体产于浅部。矿区位于由一系列走向Nw—N的断块山脉构成的俄勒冈州中南部。分析与采样程序针叶和细枝在80℃温度下干燥一整夜,在隔火炉内于550℃时灰化,用上水煮解、蒸发至初干,最后配制成25ml25%HCl的溶液。其中10ml的样品用于Au,1ml用于As的分析。在做甲基异丁基甲酮(MIBK)萃取后用石墨炉/原子吸收分光光度计测定Au。

关键词：金矿生物地球化学样品金砷

Tribological interactions of 3D printed polyurethane and polyamide with water-responsive skin model

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Friction 2022年第1期10卷 159-166页

作者： Ashish K.KASAR ashton CHAN Victor SHAMANAEV Pradeep l.MENEZES Department of Mechanical Engineering University of NevadaReno NV 89557USA Department of Mechanical Engineering New York UniversityNew York 11201USA Department of Mechanical Engineering University of NevadaLas Vegas NV 89154USA

3D printing in the textile and fashion industry is a new emerging *** of 3D printing for designing clothes and other wearable accessories require tribological and biological understanding of 3D printing plastics against the complex human skin to mitigate skin-friction related ailments such as calluses and *** study provides tribological insight in search of an optimal 3D printable material that has minimal friction against the *** low friction 3D printable materials,thermoplastic polyurethane(TPU)and polyamide(TPA)were chosen and tribological testing was carried out against a water responsive skin *** skin model was synthesized using a gelatine based model made with cotton and crosslinked with *** testing of TPU/TPA against the skin model in dry and wet conditions were *** higher coefficient of friction(COF)was observed in the wet condition compared to the dry *** overcome the higher friction,TPA/TPU-sodium polyacrylate composites were prepared by heat pressing that significantly reduced COF of TPU and TPA by~40%and 75%,respectively,in wet conditions.

关键词： plastics friction polyurethane

Novel Technique for All-Optical Clock Extraction Using Fiber Bragg Gratings

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光学学报 2003年第S1期23卷 597-598页

作者： M. Attygalle B. ashton A. Nirmalathas l. Poladian w. Padden Australian Photonics Cooperative Research Centre Photonics Research Laboratory Department of Electrical and Electronic Engineering The University of Melbourne VIC 3010 Australia. Optical Fibre Technology Centre APCRC University of Sydney NSW 1430 Australia

we demonstrate a simple passive technique, using phase shifted fibre Bragg gratings, for extraction of optical clock signals from RZ optical data signals. The generation of an optical clock signal at 12.5 GHz from a 12.5 Gbs RZ optical data stream is experimentally demonstrated with simulation of optical clock extraction at 10 GHz from 40 Gbs OTDM data streams.

关键词： Fiber Bragg Gratings clock extraction data streams

Beginning from the end:the presynaptic terminal as a pathomechanism hub in frontotemporal dementia and amyotrophic lateral sclerosis

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Neural Regeneration Research 2025年第11期20卷 3217-3218页

作者： laura Huggon Emma l.Clayton UK Dementia Research Institute at King’s College london LondonUK Department of Basic and Clinical Neuroscience Institute of Psychiatry Psychology&NeuroscienceKing’s College LondonLondonUK

Frontotemporal dementia and amyotrophic lateral sclerosis:Frontotemporal dementia(F T D)and amyo t rophic lateral sclerosis(AlS)are neurodegenerative diseases with significant overlapping *** these neurodegenerative diseases affect different neuronal populations(with FTD affecting neurons of the frontal and temporal lobes,and AlS affecting upper and lower motor neurons),these two diseases are complexly *** and AlS exist on a disease spectrum,with shared genetic causes,clinical presentations,and pathologies.

关键词： diseases amyotrophic sclerosis

Multiple sclerosis is at a checkpoint: advancing the program

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Neural Regeneration Research 2025年第3期20卷 811-812页

作者： Brandon C.Smith Jessica l.williams Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Biological Geologicaland Environmental SciencesCleveland State UniversityClevelandOHUSA

Multiple sclerosis(MS) is a chronic inflammatory and demyelinating disease of the central nervous system(CNS). Patients with MS experience sensory and motor function loss due to myelin and/or axon damage perpetuated b... 详细信息

关键词： Hauser sclerosis damage

Generation of brain vascular heterogeneity:recent advances from the perspective of angiogenesis

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Neural Regeneration Research 2025年第7期20卷 2013-2014页

作者： Nathanael J.lee Ryota l.Matsuoka Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Molecular Medicine Cleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOHUSA

Heterogeneous proper t i es of vascular endothelial cells in the brain:The brain displays large energy dynamics and consumption,and this high level of metabolic demands is fulfilled by a continuous supply of glucose and oxygen through its vascular *** vasculature consists of highly divergent blood vessel branches,giving rise to a dense network of capillaries that supply blood to all cells across the *** elaborated vascular network is thought to develop via angiogenesis,a process in which new blood vessels grow from pre-existing *** capillaries exhibit organotypic features distinct from other tissues and are formed primarily by two major endothelial cell(EC)types:those that form the semi-permeable blood-brain barrier(BBB)and those that develop highly permeable pores known as fenestrae(Matsuoka et al.,2022).The structural and functional differences between BBB and fenestrated vascular ECs represent a fundamental feature of brain vasculature and form the foundation for both brain function and homeostasis.

关键词： angiogenesis homeostasis network

HARDENING OF l1_2-ORDERED Co_3Ti BY PRECIPITATION OF FCC-Co PHASE

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Acta Metallurgica Sinica(English letters) 1998年第1期11卷 33-38页

作者： w.H.Tian S.l.Hu M.Nemoto Univ of Science and Technology Beijing Beijing China

The Co3 Ti phase hardens appreciably by the fine precipitation of disordered fcc Co-rich phase upon aging after quenching from solution annealing temperature. Transmission electron microscope (TEM)observations revealed that the precipitates are platelet in shape, lying nearly parallel to the {100} planes of the l12-ordered matrix, and perfectly coherent with the matrix lattice at the beginning of aging. The high temperature strength increases appreciably with the fine precipitation of disondered Co-rich phase over the whole temperature range investigated. TEM observations of the deformed alloys after underaging revealed that saperdislocations are pinned by precipitates indicating an attractive interaction between dislocations and precipitates.

关键词： Co_3 Ti age-hardening precipitate deformation mechanism microstructure

Characterization of Gibberellin Receptor Mutants of Barley （Hordeum vulgare l.）

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Molecular Plant 2008年第2期1卷 285-294页

作者： Peter M. Chandler Carol A. Harding Anthony R. ashton Mark D. Mulcair Nicholas E. Dixonb lewis N. Manderb CSIRO Plant Industry GPO Box 1600 Canberra ACT 2601 Australia Research School of Chemistry Australian National University Canberra ACT 0200 Australia

The sequence of Gidl （a gene for a gibberellin （GA） receptor from rice） was used to identify a putative orthologue from barley. This was expressed in E. coil, and produced a protein that was able to bind GA in vitro with both structural specificity and saturability. Its potential role in GA responses was investigated using barley mutants with reduced GA sensitivity （gsel mutants）. Sixteen different gsel mutants each carried a unique nucleotide substitution in this sequence. In all but one case, these changes resulted in single amino acid substitutions, and, for the remaining mutant, a substitution in the 5＇ untranslated region of the mRNA is proposed to interfere with translation initiation. There was perfect linkage in segregating populations between new mutant alleles and the gsel phenotype, leading to the conclusion that the putative GID1 GA receptor sequence in barley corresponds to the Gsel locus. Determination of endogenous GA contents in one of the mutants revealed enhanced accumulation of bioactive GA1, and a deficit of C20 GA precursors. All of the gsel mutants had reduced sensitivity to exogenous GA3, and to AC94377 （a GA analogue） at concentrations that are normally ＇saturating＇, but, at much higher concentrations, there was often a considerable response. The comparison between barley and rice mutants reveals interesting differences between these two cereal species in GA hormonal physiology.

关键词： .Receptor Mutants Barley Hordeum GA receptor barley mutants different gse