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Geoscience Frontiers 2019年第1期10卷 149-164页

作者： Raphael Quentin de Gromard Christopher L.Kirkland Heather m.Howard michael T.D.Wingate Fred Jourdan Brent I.A.mc Innes martin Danisik Noreen J.evans Bradley J.mcDonald R.Hugh Smithies Geological Survey of Western Australia Department of Mines Industry Regulation and Safety School of Earth and Planetary Science/John de Laeter Centre/TIGeR Curtin University

The post-mesoproterozoic tectonometamorphic history of the musgrave Province, central Australia, has previously been solely attributed to intracontinental compressional deformation during the 580 -520 ma Petermann Orogeny. However, our new structurally controlled multi-mineral geochronology results,from two north-trending transects, indicate protracted reactivation of the Australian continental interior over ca. 715 million years. The earliest events are identified in the hinterland of the orogen along the western transect. The first tectonothermal event, at ca. 715 ma, is indicated by40 Ar/39 Ar muscovite and U e Pb titanite ages. Another previously unrecognised tectonometamorphic event is dated at ca. 630 ma by Ue Pb analyses of metamorphic zircon rims. This event was followed by continuous cooling and exhumation of the hinterland and core of the orogen along numerous faults, including the Woodroffe Thrust,from ca. 625 ma to 565 ma as indicated by muscovite, biotite, and hornblende40 Ar/39 Ar cooling ages. We therefore propose that the Petermann Orogeny commenced as early as ca. 630 ma. Along the eastern transect,40 Ar/39 Ar muscovite and zircon(Ue Th)/He data indicate exhumation of the foreland fold and thrust system to shallow crustal levels between ca. 550 ma and 520 ma, while the core of the orogen was undergoing exhumation to mid-crustal levels and cooling below 600-660℃. Subsequent cooling to 150 -220℃ of the core of the orogen occurred between ca. 480 ma and 400 ma(zircon [Ue Th]/He data)during reactivation of the Woodroffe Thrust, coincident with the 450 -300 ma Alice Springs *** of the footwall of the Woodroffe Thrust to shallow depths occurred at ca. 200 ma. more recent tectonic activity is also evident as on the 21 may, 2016(Sydney date), a magnitude 6.1 earthquake occurred, and the resolved focal mechanism indicates that compressive stress and exhumation along the Woodroffe Thrust is continuing to the present day. Overall, these results

关键词： Intracontinental deformation Thermochronology Petermann orogen musgrave Province Plate tectonics Cratonization

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中子孔隙度测井井眼影响补偿的新方法

测井与射孔 2000年第3期3卷 59-63页

作者：陈雷 evans,m 胜利测井公司

中子孔隙度测井受到诸如井眼尺寸、形状及仪器状态等不利影响，为补偿这些影响，仪器采用两个探测器：一个位于离源较远的位置用于测量地层孔隙度，另一个位于离源较近的位置用于测量几何形状变化影响。用长短源距计数率相比来减小受到... 详细信息

中子孔隙度测井受到诸如井眼尺寸、形状及仪器状态等不利影响，为补偿这些影响，仪器采用两个探测器：一个位于离源较远的位置用于测量地层孔隙度，另一个位于离源较近的位置用于测量几何形状变化影响。用长短源距计数率相比来减小受到的几何影响，但这还不够，还必须对井眼尺寸、形状及仪器状态等进行校正。通过修改长短源距计数比率，确定长源距探测井计数率函数，使两个探测器在仪器附近有近似的径向响应，提高对几何改变的补偿。

关键词：中子孔隙度测井放射性测井井眼影响补偿

O2结构Li_y[mn_(1-x)m_x]O_2(m=Cr,mg)的合成及结构研究

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化学学报 2003年第6期61卷 858-862页

作者：路艳罗卫敏杨文胜 evans D.G. 段雪北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029

由高温焙烧法制备层状前驱体Na2 /3 [mn1-xmx]O2 (m =Cr,mg) ,再经离子交换反应得到层状O2结构产物Liy [mn1-xmx]O2 .XRD表明Liy[mn1-xmx]O2 属六方晶系 ,P3ml空间群 .Cr的添加量对前驱体的晶体结构有很大影响 :随着x值的增大 ,前驱体... 详细信息

由高温焙烧法制备层状前驱体Na2 /3 [mn1-xmx]O2 (m =Cr,mg) ,再经离子交换反应得到层状O2结构产物Liy [mn1-xmx]O2 .XRD表明Liy[mn1-xmx]O2 属六方晶系 ,P3ml空间群 .Cr的添加量对前驱体的晶体结构有很大影响 :随着x值的增大 ,前驱体逐渐由层状P2结构Na2 /3 [mn1-xCrx]O2 向正交结构Na4mn9O18转变 .由SEm可以看到样品Liy[mn1-xCrx] O2 (x≤ 0 .0 5 )具有六方层状结构 .XPS分析结果表明样品Liy[mn0 .95Cr0 .0 5]O2 表面上的mn和Cr分别以mn4+和Cr4+存在 ,并且表面中Cr相对含量高于体相 ,而样品Liy[mn0 .90 mg0 .10 ]O2 的表面mn和mg分别以mn4+和mg2 +存在。

关键词：层状材料晶体结构合成表面分析锂锰复合氧化物锂离子二次电池正极材料氧分子

Channel Evolution of Sandy Reservoir Sediments Following Low-Head Dam Removal, Ottawa River, Northwestern Ohio, U.S.A.

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Open Journal of modern Hydrology 2014年第2期4卷 44-56页

作者： Nathan Harris James E. evans Department of Geology Bowling Green State University Bowling Green USA Department of Geology Bowling Green State University Bowling Green USA Pennsylvania General Energy Company Warren USA

Dozens of low-head dams are removed annually for reasons of obsolescence, financial liability, public safety, or as part of aquatic ecosystem restoration. Prior to removing a dam, hydrologic and sedimentologic studies are used to predict channel changes that would occur after the proposed dam removal. One commonly used predictive approach is a channel evolution model (CEm). However, most CEms assume that the reservoir has trapped cohesive silts and muds. This study looks at the effects of low-head dam removal on a reservoir in filled with sand-rich sediment. The Secor Dam (2.5 m tall, 17 m wide) was constructed on the Ottawa River in northwestern Ohio (USA) during 1928 and was removed in 2007. High resolution channel cross-sections were measured at 17 locations prior to dam removal and re-measured every approximately 30 days for 6 months following the removal. Sediment sampling, sediment traps, substrate sampling, differential GPS tracking of channel bed forms and sediment coring were also used to characterize the channel sediment response to dam removal. Breaching of the dam produced a diffuse nickzone which was the width of the channel and about 10 m in length. One initial response was downstream migration of a sediment wave at rates up to 0.5 m/hr. The overall effect was erosion of the former reservoir to a distance of 150 m upstream of the former dam. Portions of the former reservoir were incised >1 m. Within the first 6 months after removal, approximately 800 m3 of sand had been mobilized from the former reservoir, transported downstream past the former dam, and had primarily in-filled pre-existing pools within a reach approximately 150 m downstream of the former dam. This behavior significantly differs from the predicted results of current CEms which anticipate a first flush of suspended sediment and minor deposition of bed load materials in the channel downstream of the former dam.

关键词： Dams Reservoir Sediment Dam Removals Channel Evolution model (CEm)

Subsurface Facies Analysis of the Late Cambrian mt. Simon Sandstone in Western Ohio (midcontinent North America)

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Open Journal of Geology 2012年第2期2卷 35-47页

作者： Aram Saeed James E. evans Department of Geology Bowling Green State University Bowling Green USA Exxonmobil Exploration Company Houston USA

The Cambrian mt. Simon Sandstone (mSS) is a possible unconventional gas reservoir in the Illinois, michigan, and Appalachian Basins, but comparatively little is known about the unit. This study used core and well logs from two deep exploratory wells to interpret the depositional environment of the mSS under western Ohio, where the mSS is about 120 m thick and found 1060 m below ground surface. In western Ohio, the mSS unconformably overlies the Precambrian middle Run Formation, is conformably overlain by the Cambrian Eau Claire Formation, and has a distinctive gamma-ray log-signature. In well DGS-2627, the mSS consists of tan, friable, moderately sorted, rounded, coarse- to very coarse-grained siliceous quartz arenite with minor heterolithic sandstone-mudstone couplets (rhythmites) and quartz granule conglomerate. Features indicative of tidally-influenced, shallow marine settings include tidal rhythmites, lenticular-, flaser-, and wavy-bedding, herringbone cross-bedding, mud-drapes, tidal bundles, reactivation surfaces, intraclasts, and bioturbation. The unit generally coarsens- and thickens-upward, and is interpreted as migration of a tidally-influenced transgressive barrier sequence. A subsurface facies model for the mSS is developed by interpreting geophysical logs and cores from DGS-2627l, and this model is semi-quantitatively tested by first interpreting well BP-4 using geophysical logs alone, then confirming the results using core.

关键词： mt. Simon Sandstone Cambrian Ohio Depositional Environment Subsurface Facies Analysis Natural Gas Petroleum midcontinent North America

Weight loss increases skeletal muscle mitochondrial energy efficiency in obese mice

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Life metabolism 2023年第2期2卷 23-34页

作者： Patrick J.Ferrara marisa J.Lang Jordan m.Johnson Shinya Watanabe kelsey L.mcLaughlin John Alan maschek Anthony R.P.Verkerke Piyarat Siripoksup Amandine Chaix James E.Cox kelsey H.Fisher-Wellman Katsuhiko Funai Diabetes&metabolism Research Center University of UtahSalt Lake CityUtah 84112United States Department of Nutrition&Integrative Physiology University of UtahSalt Lake CityUtah 84112United States East Carolina Diabetes&Obesity Institute East Carolina UniversityGreenvilleNorth Carolina 27834United States Department of Physiology East Carolina UniversityGreenvilleNorth Carolina 27834United States metabolomics Core Research Facility University of UtahSalt Lake CityUtah 84112United States molecular medicine Program University of UtahSalt Lake CityUtah 84112United States Department of Biochemistry University of UtahSalt Lake CityUtah 84112United States

Weight loss from an overweight state is associated with a disproportionate decrease in whole-body energy expenditure that may contribute to the heightened risk for weight *** suggests that this energetic mismatch originates from lean *** this phenomenon is well documented,the mechanisms have remained *** hypothesized that increased mitochondrial energy efficiency in skeletal muscle is associated with reduced expenditure under weight ***(WT)male C57BL6/N mice were fed with high-fat diet for 10 weeks,followed by a subset of mice that were maintained on the obesogenic diet(OB)or switched to standard chow to promote weight loss(WL)for additional 6 *** energy efficiency was evaluated using high-resolution respirometry and *** spectrometric analyses were employed to describe the mitochondrial proteome and *** loss promoted~50%increase in the efficiency of oxidative phosphorylation(ATP produced per O_(2) consumed,or P/O)in skeletal ***,Weight loss did not appear to induce significant changes in mitochondrial proteome,nor any changes in respiratory supercomplex ***,it accelerated the remodeling of mitochondrial cardiolipin(CL)acyl-chains to increase tetralinoleoyl CL(TLCL)content,a species of lipids thought to be functionally critical for the respiratory *** further show that lowering TLCL by deleting the CL transacylase tafazzin was sufficient to reduce skeletal muscle P/O and protect mice from diet-induced weight *** findings implicate skeletal muscle mitochondrial efficiency as a novel mechanism by which weight loss reduces energy expenditure in obesity.

关键词： energy efficiency energy expenditure mitochondria oxidative phosphorylation phospholipids weight loss

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层状前体镁铁水滑石及磁性材料的制备及表征

无机化学学报 2002年第8期18卷 777-781页

作者：周彤战可涛李峰 evans D.G. 段雪张密林北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029 哈尔滨工程大学哈尔滨150001

本文提出了利用镁铁水滑石作为磁性材料前体再经高温焙烧制备尖晶石型铁氧体的思路,深入研究了水滑石的制备工艺及结构性能并初步探讨了其焙烧后的磁学性能。由共沉淀法合成了mg/Fe摩尔比为2,3,4,6的镁铁水滑石,XRD结果表明随镁铁比增... 详细信息

本文提出了利用镁铁水滑石作为磁性材料前体再经高温焙烧制备尖晶石型铁氧体的思路,深入研究了水滑石的制备工艺及结构性能并初步探讨了其焙烧后的磁学性能。由共沉淀法合成了mg/Fe摩尔比为2,3,4,6的镁铁水滑石,XRD结果表明随镁铁比增大、晶化温度的升高及晶化时间的延长,水滑石的晶体结构规整性增强;热重-差热结果显示镁铁水滑石的分解有两个过程,随着镁铁比增大,水滑石的热稳定性提高。高温焙烧后的镁铁水滑石具有较好的磁学性能。

关键词：层状前体磁性材料制备表征镁铁水滑石共沉淀热分解磁性铁氧体

Carotid Intima-media Thickness measurements： Relations with Atherosclerosis, Risk of Cardiovascular Disease and Application in Randomized Controlled Trials

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Chinese medical Journal 2016年第2期129卷 215-226页

作者： michiel L Bots Gregory W evans Charles H Tegeler Rudy meijer Julius Center for Health Sciences and Primary Care University Medical Center Utrecht Utrecht The Netherlands Department of Biostatistical Sciences and Neurology Wake Forest School of Medicine Winston-Salem NC USA Department of Neuiology Ward A Riley Ultrasound Center Wake Forest School of Medicine Medical Center Boulevard Winston-Salem NC USA

Cardiovascular disease （CVD） is the leading cause of death worldwide and contributes considerably to morbidity The underlying cause is atherosclerosisThe development of new preventive therapies is one of the steps to control the CVD epidemic. It is increasingly demanded that promising therapies be evaluated in trials using cardiovascular （CV） morbidity and mortality （m and m） as a primary outcome.

关键词： Atherosclerosis Cardiovascular Disease Prevention Trials

Isolative Synthesis and Characterization of Cellulose and Cellulose Nanocrystals from Typha angustifolia

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Open Journal of Applied Sciences 2024年第9期14卷 2443-2459页

作者： Lynda S. mesoppirr evans K. Suter Wesley N. Omwoyo Nathan m. Oyaro Simphiwe m. Nelana Department of mathematics and Physical Science Maasai Mara University Narok Kenya Biotechnology and Chemistry Department Vaal University of Technology Vanderbijlpark South Africa

The application potential of cellulosic materials in natural composites and other fields needs to be explored to develop innovative, sustainable, lightweight, functional biomass materials that are also environmentally friendly. This study investigated Typha angustifolia (Typha sp.) as a potential new raw material for extracting cellulose nanocrystals (CNCs) for application in wastewater treatment composites. Alkaline treatments and bleaching were used to remove cellulose from the stem fibres. The CNCs were then isolated from the recovered cellulose using acid hydrolysis. The study showed a few distinct functional groups (O-H, -C-H, =C-H and C-O, and C-O-C) in the Fourier Transform Infrared (FTIR) spectra. A scanning electron microscope (SEm) revealed the smooth surface of CPC and CNCs, which resulted from removing lignin and hemicellulose from powdered Typha angustifolia. Based on the crystalline index, the powdered Typha angustifolia, CPC, and CNCs were 42.86%, 66.94% and 77.41%. The loss of the amorphous section of the Typha sp. fibre resulted in a decrease in particle size. It may be inferred from the features of a Typha sp. CNC that CNCs may be employed as reinforcement in composites for wastewater treatment.

关键词： Typha angustifolia Cellulose Acid Hydrolysis Chemically Purified Cellulose Cellulose Nanocrystals