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On the radiogenic heat production of metamorphic,igneous,and sedimentary rocks

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Geoscience Frontiers 2018年第6期9卷 1777-1794页

作者： d.Hasterok M.gard J.Webb department of Earth sciences University of AdelaideNorth TerraceSA5005Australia Centre for Tectonics Research and Exploration(TRaX) University of AdelaideNorth TerraceSA5005Australia Ramelius Resources Ltd. East PerthWA 6005Australia

sedimentary rocks cover-73% of the Earth's surface and metamorphic rocks account for approximately91% of the crust by volume. Understanding the average behavior and variability of heat production for these rock types are vitally important for developing accurate models of lithospheric temperature. We analyze the heat production of ～204,000 whole rock geochemical data to quantify how heat production of these rocks varies with respect to chemistry and their evolution during metamorphism. The heat production of metaigneous and metasedimentary rocks are similar to their respective protoliths. Igneous and metaigneous samples increase in heat production with increasing siO_2 and K_2 O, but decrease with increasing FeO, MgO and CaO. sedimentary and metasedimentary rocks increase in heat production with increasing Al_2 O_3, FeO, TiO_2, and K_2 O but decrease with increasing CaO. For both igneous and sedimentary rocks, the heat production variations are largely correlated with processes that affect K_2 O concentration and covary with other major oxides as a consequence. Among sedimentary rocks,aluminous shales are the highest heat producing(2.9 μW^(-3)) whereas more common iron shales are lower heat producing(1.7 μW m^(-3)). Pure quartzites and carbonates are the lowest heat producing sedimentary rocks. Globally, there is little definitive evidence for a decrease in heat production with increasing metamorphic grade. However, there remains the need for high resolution studies of heat production variations within individual protoliths that vary in metamorphic grade. These results improve estimates of heat production and natural variability of rocks that will allow for more accurate temperature models of the lithosphere.

关键词： Heat generation density Metamorphic rocks sedimentary rocks Igneous rocks Continental lithosphere

Nanoscale resetting of the Th/Pb system in an isotopically-closed monazite grain: A combined atom probe and transmission electron microscopy study

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Geoscience Frontiers 2019年第1期10卷 65-76页

作者： A.-M.seydoux-Guillaume d.Fougerouse A.T.Laurent E.gardés s.M.Reddy d.W.saxey Univ Lyon UJM-Saint-Etienne CNRS IRD CNRs Université Clermont Auvergne school of Earth and Planetary sciences Curtin University Geoscience Atom Probe Advanced Resource Characterisation Facility John de Laeter Centre Curtin University Centre de recherche sur les Ions les Matériaux et la Photonique (CIMAP) department of Physics and Astronomy Curtin University

Understanding the mechanisms of parent-daughter isotopic mobility at the nanoscale is key to rigorous interpretation of Ue The Pb data and associated dating. Until now, all nanoscale geochronological studies on geological samples have relied on either Transmission Electron Microscope(TEM) or Atom Probe Microscopy(APM) characterizations alone, thus suffering from the respective weaknesses of each technique. Here we focus on monazite crystals from a ~1 Ga, ultrahigh temperature granulite from Rogaland(Norway). This sample has recorded concordant UeP b dates(measured by LA-ICP-Ms) that range over 100 My, with the three domains yielding distinct isotopic Ue Pb ages of 1034 ± 6 Ma(d1; srich core), 1005 ± 7 Ma(d2), and 935 ± 7 Ma(d3), respectively. Combined APM and TEM characterization of these monazite crystals reveal phase separation that led to the isolation of two different radiogenic Pb(Pb*) reservoirs at the nanoscale. The s-rich core of these monazite crystals contains Cae srich clusters, 5 -10 nm in size, homogenously distributed within the monazite matrix with a mean interparticle distance of 40 -60 nm. The clusters acted as a sink for radiogenic Pb(Pb*) produced in the monazite matrix, which was reset at the nanoscale via Pb diffusion while the grain remained closed at the micro-scale. Compared to the concordant ages given by conventional micro-scale dating of the grain,the apparent nano-scale age of the monazite matrix in between clusters is about 100 Myr younger, which compares remarkably well to the duration of the metamorphic event. This study highlights the capabilities of combined APM-TEM nano-structural and nano-isotopic characterizations in dating and timing of geological events, allowing the detection of processes untraceable with conventional dating methods.

关键词： Monazite Nanoscale resetting Nano-clusters APM TEM UHT metamorphism

Influence of Interface on the Behavior of Polypropylene Reinforced with short Glass Fibers

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Influence of Interface on the Behavior of Polypropylene Rein...

Experimental and numerical study of the fragmentation of expanding warhead casings by using different numerical codes and solution techniques

第十三届国际复合材料会议

作者： E.ségard s.Benmedakhene A.Laksimi d.Laǐ Université de Technologie de Compiègne Laboratoire Roberval UMR CNRS Polymères et composites BP 20529 60205 Compiègne France Université de Technologie de Compiègne Laboratoire Roberval UMR CNRS Polymères et composites BP 20529 60205 Compiègne France Université de Technologie de Compiègne Laboratoire Roberval UMR CNRS Polymères et composites BP 20529 60205 Compiègne France Université de Technologie de Compiègne Laboratoire Roberval UMR CNRS Polymères et composites BP 20529 60205 Compiègne France

＜正＞Tensile tests and tensile creep-recovery tests are realized on polypropylene with 40% in mass of short glass fibers. The quality of interface matrix-fibers influence the elastic, viscoelastic and viscoplastic behavior of materials （1）. Tensile Tests The study is realized on the polypropylene reinforced with 40% in mass of short glass fiber. We considered two types of fiber which are traeted and untreated short glass fiber. In the first time, monotonous uniaxial tensile tests until fracture with imposed displacement, were carried

关键词： polypropylene treated and untreated short glass fibers interface monotonous tensile tests creep tests creep-recovery tests damage acoustic emission

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defence Technology（防务技术） 2014年第2期10卷 161-176页

作者： John F.MOXNEs Anne K.PRYTZ Фyvind FRФYLANd siri KLOKKEHAUG stian sKRIUdALEN Eva FRIIs Jan A.TELANd Cato dФRUM gard Фd.gardsTUEN Land systems division.Norwegian defence Research Establishment P.O.Box 25 Nammo Raufoss As.P.O.Box 162

There has been increasing interest in numerical simulations of fragmentation of expanding warheads in *** there is a pressure on developers of leading commercial codes,such as *** and IMPETUs *** implement the reliable fracture models and the efficient solution *** applicability of the Johnson—Cook strength and fracture model is evaluated by comparing the fracture behaviour of an expanding steel casing of a warhead with *** numerical codes and different numerical solution techniques,such as Eulerian,*** particle hydrodynamics(sPH).and the corpuscular models recently implemented in IMPETUs Afea are *** the same solution techniques and material models we find that the codes give similar *** sPH technique and the corpuscular technique are superior to the Eulerian technique and the Lagrangian technique(with erosion) when it is applied to materials that have fluid like behaviour such as the explosive and the *** Eulerian technique gives much larger calculation time and both the Lagrangian and Eulerian techniques seem to give less agreement with our *** more correctly simulate the fracture behaviours of the expanding steel casing,we applied that ductility decreases with strain *** phenomena may be explained by the realization of adiabatic shear *** implemented node splitting algorithm in IMPETUs Afea seems very promising.

关键词：技术试验数字代码数值模拟弹头光滑粒子流体动力学 Ls-dYNA 外壳数值求解方法

A micromirror array with annular partitioning for high-speed random-access axial focusing

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Light(science & Applications) 2020年第1期9卷 241-255页

作者： Nathan Tessema Ersumo Cem Yalcin Nick Antipa Nicolas Pegard Laura Waller daniel Lopez Rikky Muller The University of California Berkeley and University of CaliforniaSan Francisco Graduate Program in BioengineeringBerkeleyCA 94720USA department of Electrical Engineering&Computer sciences University of CaliforniaBerkeleyCA 94720USA department of Applied Physical sciences University of North Carolina at Chapel HillChapel HillNC 27514USA Chan Zuckerberg Biohub San FranciscoCA 94158USA Physical Measurement Laboratory National Institute of Standards and TechnologyGaithersburgMD 20899USA

dynamic axial focusing functionality has recently experienced widespread incorporation in microscopy,augmented/virtual reality(AR/VR),adaptive optics and material ***,the limitations of existing varifocal tools continue to beset the performance capabilities and operating overhead of the optical systems that mobilize such *** varifocal tools that are the least burdensome to operate(*** crystal,elastomeric or optofluidic lenses)suffer from low(≈100 Hz)refresh ***,the fastest devices sacrifice either critical capabilities such as their dwelling capacity(*** gradient lenses or monolithic micromechanical mirrors)or low operating overhead(*** mirrors).Here,we present a general-purpose random-access axial focusing device that bridges these previously conflicting features of high speed,dwelling capacity and lightweight drive by employing lowrigidity micromirrors that exploit the robustness of defocusing phase ***,the device consists of an 8.2mm diameter array of piston-motion and 48-μm-pitch micromirror pixels that provide 2πphase shifting for wavelengths shorter than 1100 nm with 10-90% settling in 64.8μs(i.e.,15.44 kHz refresh rate).The pixels are electrically partitioned into 32 rings for a driving scheme that enables phase-wrapped operation with circular symmetry and requiress demonstrated the array’s wide focusing range with a measured ability to target 29 distinct resolvable depth ***,the features of the proposed array offer the potential for compact,straightforward methods of tackling bottlenecked applications,including high-throughput single-cell targeting in neurobiology and the delivery of dense 3d visual information in AR/VR.

关键词： mirror axial random

放射医师何时表现最佳:筛查性乳腺片诊断的学习曲线

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国际医学放射学杂志 2010年第1期 77-78页

作者： d.L.Miglioretti C.C.gard P.A.Carney T.L.Onega d.s.Buist E.A.sickles 田凤娟 Group Health Research Institute Group Health Cooperative

目的研究有没有接受乳腺影像学专科资质培训获得临床经验的放射医师在筛查性乳腺片诊断中水平的差异。材料与方法本研究项目经伦理委员会同意,符合美国HIPAA法案。我们考察了从1996年—2005年间,在280个向乳腺癌监管联合会提供数据的机... 详细信息

目的研究有没有接受乳腺影像学专科资质培训获得临床经验的放射医师在筛查性乳腺片诊断中水平的差异。材料与方法本研究项目经伦理委员会同意,符合美国HIPAA法案。我们考察了从1996年—2005年间,在280个向乳腺癌监管联合会提供数据的机构中,参与诊断筛查性乳腺X线片的231名放射医师。这

关键词：放射医师资质临床经验乳腺乳房学习曲线筛查

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报告乳腺钼靶密度:屏片和数字采集

国际医学放射学杂志 2013年第3期 263-263页

作者： J.A.Harvey C.C.gard d.L.Miglioretti B.C.Yankaskas K.Kerlikowske d.s.Buist 田凤娟 department of Radiology University of Virginia

目的验证美国放射学院乳腺影像报告和数据系统(BI-RAds)乳腺密度分类中放射科医生所报告的使用数字钼靶所获得乳腺密度低于屏片(Fs)钼靶这一假设。材料与方法本研究经机构审查委员会批准并符合HIPAA。人口数据、风险因素与BI-RAds乳腺... 详细信息

目的验证美国放射学院乳腺影像报告和数据系统(BI-RAds)乳腺密度分类中放射科医生所报告的使用数字钼靶所获得乳腺密度低于屏片(Fs)钼靶这一假设。材料与方法本研究经机构审查委员会批准并符合HIPAA。人口数据、风险因素与BI-RAds乳腺密度分类从乳腺癌监控联盟中5个钼靶检查登记处获得。所有的参与者都获得主动、被动或放弃的知情同意权。入选的病例为年龄≥40岁的女性,在2000年1月1日—2009年12月31日间的36个月内至少接受2次钼靶检查。之前患乳腺癌、病灶增大或使用过已知影响乳腺密度药物的女性被排除在外。主要样本是89639名接受Fs和数字钼靶两种检查的妇女。对照组包括259046名接受两次Fs钼靶检查的妇女和87066名接受两次数字钼靶检查妇女。BI-RAds密度按照两种检查的次序及两次解释而制成交叉列表。结果无论何种采集方法,女性乳腺密度改变的百分比从一次阅片到下一次都是相似的。Fs在数字钼靶摄片之前的19.8%女性乳腺密度降低,而数字钼靶在Fs钼靶摄片前的17.1%女性乳腺密度降低。同样,无论何种采集方法,基于第二次钼靶检查所报告乳腺密度降低的百分比也类似,从15.8%到19.8%。无论何种钼靶检查类型配对,阅片密度一致性的百分比也类似,从67.3%到71.0%。结论研究结果显示根据采集方法所报告BI-RAds乳腺密度分类没有区别。所报告的BI-RAds密度分类可应用到Fs、数字或两种采集方式可用的乳腺癌风险模型中。

关键词：钼靶检查 BI 女性 Fs 密度钼靶摄片

氩离子电凝术与多极电凝用于Barrett食管消融术的随机临床试验

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世界核心医学期刊文摘（胃肠病学分册） 2005年第8期1卷 28-29页

作者： dulai G.s Jensen d.M Cortina G 郝筱倩 VA Gtr. Los Angeles H lthcare. system CURE Digest. Dis.Research Center Bldg. 115 11301 Wilshire Blv d. Los Angeles CA 90073 United States.Dr

Background: Endoscopic ablation of Barrett’s esophagus has been described in which various thermocoagulation modalities are used in combination with a high d ose of a proton pump inhibitor. No randomized comparison of ablation strategies has been published. Methods: Referred patients were screened to identify those w ith Barrett’s es- ophagus 2 to 7 cmin length,without high-grade dysplasia or cancer. Included p atients received pantoprazole (40 mg twice a day), followed by randomization to treatment with argon plasma coagulation (APC) or multipolar electrocoagulation ( MPEC). The primary outcome measure was the number of treatment sessions required for endoscopic ablation. Results: Of 235 patients screened, 52 were randomized. The mean length of Barrett’s esophagus was 3.1 cm in the MPEC group vs. 4.0 cm in the APC group (p = 0.03). Otherwise,the treatment groups were similar with re gard to baseline characteristics. The mean number of treatment sessions required for endoscopic ablation was 2.9 for MPEC vs. 3.8 for APC (p = 0.04) in an inten tion-to-treat analysis (p = 0.249, after adjustment for the difference in leng th of Barrett’s esophagus).The proportion of patients in which ablationwas endo scopically achieved proximal to the gastroesophageal junction was 88%for the MP EC group vs. 81%for the APC group (p = 0.68) and histologically achieved in 81%for MPEC vs. 65%for APC (p= 0.21). The mean ti me required for the first treatment session was 6 minutes with MPEC vs. 10 minut es with APC (p =0.01) in per protocol analysis. There was no serious adverse eve nt, but transient moderate to severe upper-GI symptoms occurred after MPEC in 8 %vs. 13%after APC (p = 0.64).Conclusions: Although there were no statistically significant differences, ablation of Barrett’s esophagus with pantoprazole and MPEC required numerically fewer treatment sessions, and endoscopic and histolog ic ablation was achieved in a greater proportion of patients compared with treat ment with pantop

关键词： Barrett 电凝术氩离子随机临床试验潘托拉唑治疗次数治疗周期长度差异随机筛选异常增生

埃及2000年之前丙型肝炎感染相关死亡率预期增长

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世界核心医学期刊文摘（胃肠病学分册） 2006年第8期2卷 52-53页

作者： deuffic-Burban s. Mohamed M. K. Larouze B. 孟欣颖(译) 王顺涛(校) Cresge-Labores CNRSURA362 1 rue Norbert Ségard 59016 Lille France 不详

Background/Aims: Egypt has the highest prevalence of Hepatitis C Virus (HCV) in the world, aPPArently due to mass parenteral antischistosomal therapy. Estimating the future burden of HCV in Egypt is important to support health policies to combat the epidemic. Methods: A previous back calculation model was adapted to the situation in Egypt. It combines a model of the natural history of HCV infections with available epidemiological data to back calculate the past HCV incidence from observed 1980- 1999 hepatocellular carcinoma (HCC) mortality. In turn, the HCV-related mortality burden is projected in the future due to pre- 2000 infections. Results: Compared with the observed number of HCC deaths in 1999, the model predicts a 3.5- fold increase in this mortality in the next 20 years. Globally, the model predicts a 2.4- fold increase in theHCV-related mortality. These predictions do not take into account the new infections that may occur after 2000, which would still increase the estimated future mortality burden. Conclusions: HCV-related mortality is expected at least to double in the next 20 years. The use of antiviral therapies can lower these predictions. Efficient prevention policies are needed to avoid these predictions being exceeded.

关键词：丙型肝炎感染死亡率丙型肝炎病毒(HCV) 埃及 HCV感染抗病毒治疗预测模式肝细胞肝癌抗血吸虫静脉途径