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Trilinear Hexahedra with Integral-Averaged Volumes for Nearly Incompressible Nonlinear Deformation

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Engineering（科研） 2015年第11期7卷 765-788页

作者： craig D. Foster Talisa Mohammad Nejad University of Illinois at Chicago Civil and Materials Engineering Chicago IL USA

Many materials such as biological tissues, polymers, and metals in plasticity can undergo large deformations with very little change in volume. Low-order finite elements are also preferred for certain applications, but are well known to behave poorly for such nearly incompressible materials. Of the several methods to relieve this volumetric locking, the method remains popular as no extra variables or nodes need to be added, making the implementation relatively straightforward and efficient. In the large deformation regime, the incompressibility is often treated by using a reduced order or averaged value of the volumetric part of the deformation gradient, and hence this technique is often termed an approach. However, there is little in the literature detailing the relationship between the choice of and the resulting and stiffness matrices. In this article, we develop a framework for relating the choice of to the resulting and stiffness matrices. We examine two volume-averaged choices for , one in the reference and one in the current configuration. Volume-averaged formulation has the advantage that no integration points are added. Therefore, there is a modest savings in memory and no integration point quantities needed to be interpolated between different sets of points. Numerical results show that the two formulations developed give similar results to existing methods.

关键词： Incompressibility Volumetric Locking Strain Projection b-bar F-bar Finite Element

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燕麦属细胞遗传学研究进展

热带亚热带植物学报 2017年第4期25卷 409-418页

作者：周湘英贺文琪 John Seymour HESLOP-harrison 刘青中国科学院植物资源保护与可持续利用重点实验室中国科学院华南植物园广州510650 中国科学院大学北京100049 吉首大学生物资源与环境科学学院湖南吉首416000 莱斯特大学遗传系

整理燕麦属(Avena L.)细胞遗传学研究文献,总结相关研究进展。燕麦属有7组29种植物,分属5个基因组类型(A、C、Ab、AC、ACD)。基于荧光原位杂交技术和种间杂交实验表明,A、C基因组染色体结构差异较大,A基因组二倍体物种具有等臂染色体,C... 详细信息

整理燕麦属(Avena L.)细胞遗传学研究文献,总结相关研究进展。燕麦属有7组29种植物,分属5个基因组类型(A、C、Ab、AC、ACD)。基于荧光原位杂交技术和种间杂交实验表明,A、C基因组染色体结构差异较大,A基因组二倍体物种具有等臂染色体,C基因组二倍体物种具有不等臂染色体。燕麦属植物D基因组和A基因组间分化程度较小,b基因组有可能是A基因组的变型——A′基因组。普遍观点认为A基因组二倍体物种可能是燕麦属六倍体物种母系亲本,砂燕麦(***)为该属多倍体物种A基因组祖先的假说备受争议,有学者认为加那利燕麦(***)可能是多倍体物种A或D基因组的供体。燕麦属多倍体物种基因组互换及染色体重排事件,增加燕麦属种间亲缘关系、多倍体物种基因组起源研究的困难。结合基因组学、分子细胞遗传学技术,有望为上述问题提供新证据。

关键词：基因组起源燕麦属细胞遗传学禾本科多倍体

爱尔兰海岸夏季空气颗粒物水溶性离子粒径分布研究

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海洋环境科学 2005年第4期24卷 41-44,47页

作者：黄卓尔 Roy M harrison 殷建新广州市环境监测中心站广东广州510030 Division of Environmental Health and Risk Management University of birmingham birmingham b152TTUK

研究了爱尔兰西海岸国际海洋大气研究站夏季(2002年8月12～22日)大西洋气团颗粒物中水溶性无机离子的含量与其粒径关系.海盐成分(Cl-、SO42-、Na+、Ca2+、Mg2+、K+)含量在粗颗粒物中随粒径呈双峰分布(0.8～30 μm),但Ca2+和K+受陆域源影... 详细信息

研究了爱尔兰西海岸国际海洋大气研究站夏季(2002年8月12～22日)大西洋气团颗粒物中水溶性无机离子的含量与其粒径关系.海盐成分(Cl-、SO42-、Na+、Ca2+、Mg2+、K+)含量在粗颗粒物中随粒径呈双峰分布(0.8～30 μm),但Ca2+和K+受陆域源影响,在亚微米颗粒区间出现另一分布峰(0.1～0.8 μm).二次颗粒物成分在所有颗粒物中均有检出;NO3-呈广域宽带分布,其中大部分出现在海盐主峰区(0.8～8 μm,存在Dp 1.4 μm和Dp 4.4 μm两种模态);nss-SO42-(非海盐硫酸根)和NH4+呈相关三峰分布(Dp 0.44 μm、Dp 1.4 μm和Dp 4.4 μm),CH3SO3-也呈相似三峰分布(Dp 0.44 μm、Dp 1.4 μm和Dp 8 μm),三者在亚微米颗粒区间同位出现主峰.二次颗粒物成分Dp 1.4 μm模态在海岸空气颗粒物研究文献中尚少见报道.讨论了亚微米区间二次颗粒物盐类的化学形态.TSP中nss-SO42-、NO3-、NH4+和CH3SO3-的日均浓度分别为0.279、0.171、0.158和0.041 μg/m3.

关键词：海岸空气颗粒物可溶性离子粒径分布

bioavailability Improvement of SLMs based Erythromycin Ethyl Succinate using Stearic Acid-Myrj-52-based SLM＇s

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Journal of Chemistry and Chemical Engineering 2017年第1期11卷 37-44页

作者： Uduma Eke Osonwa Stephen Olaribigbe Majekodunmi Emmanuella OnyechiN harrison Thaddeus Gugu Department of Pharmaceutics and Pharmaceutical Technology Faculty of Pharmaceutical Sciences Nnamdi Azikiwe UniversityAwka Anambra State Nigeria Department of Pharmaceutics and Pharmaceutical Technology Faculty of Pharmacy University of Uyo P.M.B 1017 UyoNigeria Department of Pharmaceutics and Pharmaceutical Microbiology and biotechnology Faculty of Pharmaceutical SciencesNnamdiAzikiwe University Awka Anambra State Nigeria

The Neighborhood Scale Variability of Airborne Particulates

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Journal of Environmental Protection 2015年第5期6卷 464-476页

作者： William A. harrison David Lary brian Nathan Alec G. Moore William b. Hanson Center for Space Sciences University of Texas at Dallas Richardson USA

Airborne particulates play a central role in both the earth’s radiation balance and as a trigger for a wide range of health impacts. Air quality monitors are placed in networks across many cities glob-ally. Typically these provide at best a few recording locations per city. However, large spatial var-iability occurs on the neighborhood scale. This study sets out to comprehensively characterize a full size distribution from 0.25 - 32 μm of airborne particulates on a fine spatial scale (meters). The data are gathered on a near daily basis over the month of May, 2014 in a 100 km2 area encompassing parts of Richardson, and Garland, TX. Wind direction was determined to be the dominant factor in classifying the data. The highest mean PM2.5 concentration was 14.1 ± 5.7 μg·m-3 corresponding to periods when the wind was out of the south. The lowest PM2.5 concentrations were observed after several consecutive days of rainfall. The rainfall was found to not only “cleanse” the air, leaving a mean PM2.5 concentration as low as 3.0 ± 0.5 μg·m-3, but also leave the region with a more uniform PM2.5 concentration. Variograms were used to determine an appropriate spatial scale for future sensor placement to provide measurements on a neighborhood scale and found that the spatial scales varied, depending on the synoptic weather pattern, from 0.8 km to 5.2 km, with a typical length scale of 1.6 km.

关键词： PM2.5 Variograms Neighborhood Scale Spatial Length

Study of CdZnTeSe Gamma-Ray Detector under Various bias Voltages

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Materials Sciences and Applications 2020年第8期11卷 553-559页

作者： Mebougna L. Drabo Stephen U. Egarievwe Utpal N. Roy benicia A. harrison Carmella A. Goree Emmanuel K. Savage Ralph b. James Department of Mechanical & Civil Engineering and Construction Management Alabama A&M University Huntsville AL USA Nuclear Engineering and Radiological Science Center Alabama A&M University Huntsville AL USA Department of Electrical Engineering and Computer Science Alabama A&M University Huntsville AL USA Department of Nonproliferation and National Security Brookhaven National Laboratory Upton NY USA Science and Technology Directorate Savannah River National Laboratory Aiken SC USA biological and Environmental Sciences Department Alabama A&M University Huntsville AL USA Department of Physics Chemistry and Mathematics Alabama A&M University Huntsville AL USA

Cadmium zinc telluride selenide (CdZnTeSe) is a new semiconductor material for gamma-ray detection and spectroscopy applications at room temperature. It has very high crystal quality compared to similar materials such as cadmium telluride and cadmium zinc telluride. The consistency of peak position in radiation detection devices is important to practical applications. In this paper, we have characterized a CdZnTeSe planar detector for bias voltages in the range of -20 V to -200 V and amplifier shaping time of 2, 3 and 6 μs. The peak position of the 59.6-keV gamma line of 241Am becomes more stable as the absolute value of the applied voltage increases. The best energy resolution of 8.5% was obtained for the 59.6-keV gamma peak at -160 V bias voltage and 3-μs shaping time. The energy resolution was relatively stable in the -120 V to -200 V range for a 6-μs shaping time. Future work will be focused on the study of the peak position and energy resolution over time.

关键词： CdZnTeSe Energy Resolution Energy-Peak Stability Gamma-Ray Spectroscopy Nuclear Detectors

Call Me, Maybe： Examining the Compliance Rates and Cost-effectiveness of a Participant-initiated Automated Telephone System with Children

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Journal of Sports Science 2015年第2期3卷 67-78页

作者： Krista Munroe-Chandler craig Hall Michelle Guerrero Danielle Tobin Department of Kinesiology University of Windsor Windsor Ontario N9B 3P4 Canada School of Kinesiology Western University London Ontario N6A 3K7 Canada

Telephone-delivered physical activity interventions have proven to be effective with adults, yet there is no research using this strategy with children. The purpose of the current study was to examine the feasibility of implementing a participant-initiated automated telephone imagery intervention with children. The outcomes of interest were compliance rates to and cost-analysis of the telephone system. Fifty-nine Grade 5 and 6 students (Mage = 10.24, SD = 0.80; 36 females) from two schools were randomized into either an imagery group or a short story group, and some individuals in both of these groups received an individual incentive and some received a class incentive. All participants were asked to call the automated system from home 3x/week for the duration of the study. The high compliance rate, the minimal cost of implementing such a system, and the ability to reach more children than a face-to-face intervention makes the telephone an attractive modality for behavior change researchers.

关键词：运动科学体育运动体育锻炼科学方法

Traumatic injury is associated with reduced deoxyribonuclease activity and dysregulation of the actin scavenging system

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burns & Trauma 2021年第1期9卷 558-572页

作者： Jon Hazeldine Robert J.Dinsdale David N.Naumann Animesh Acharjee Jonathan R.b.bishop Janet M.Lord Paul harrison Institute of Inflammation and Ageing University of BirminghamEdgbastonBirminghamWest MidlandsB152TTUnited Kingdom National Institute for Health Research Surgical Reconstruction and Microbiology Research Centre Heritage BuildingQueen Elizabeth Hospital BirminghamMindelsohnWayEdgbastonBirminghamWest MidlandsB152THUnited Kingdom Scar Free Foundation birmingham Centre for burns Research University Hospital Birmingham Foundation TrustQueen Elizabeth Hospital BirminghamMindelsohnWayEdgbastonBirminghamWest MidlandsB152THUnited Kingdom Academic Department of Military Surgery and Trauma Royal Centre for Defence MedicineQueen Elizabeth Hospital BirminghamMindelsohnWayEdgbastonBirminghamWest MidlandsB152THUnited Kingdom Institute of Cancer and Genomic Sciences Centre for Computational BiologyUniversity of BirminghamEdgbastonBirminghamWest MidlandsB152TTUnited Kingdom

background:Traumatic injury is associated with increased concentrations of cell-free DNA(cfDNA)in the circulation,which contribute to post-injury *** endonuclease deoxyribonuclease 1(DNase-1)is responsible for removing 90%of circulating ***,DNase activity was reported to be significantly reduced following major non-traumatic brain injury(TbI),but the processes responsible were not ***,it is not known how quickly following injury DNase activity is reduced and whether this also occurs after ***:At 3 post-injury time points(≤1,4–12 and 48–72 hours),blood samples were obtained from 155 adult trauma patients that had sustained an isolated TbI(n=21),TbI with accompanying extracranial injury(TbI^(+))(n=53)or an extracranial injury only(ECI)(n=81).In addition to measuring cfDNA levels and the activity and expression of DNase,circulating concentrations of monomeric globular action(G-actin),an inhibitor of DNase-1,and the actin scavenging proteins gelsolin(GSN)and vitamin D binding protein(VDbP)were determined and values compared to a cohort of healthy ***:Significantly elevated concentrations of plasma cfDNA were seen in TbI,TbI^(+)and ECI patients at all study time points when compared to healthy *** levels were significantly higher at≤1 hour post-injury in ECI patients who subsequently developed multiple organ dysfunction syndrome when compared to those who did *** DNase-1 protein was significantly elevated in all patient groups at all sampling time *** contrast,DNase enzyme activity was significantly reduced,with this impaired function evident in TbI^(+)patients within minutes of *** concentrations of G-actin were elevated in all patient cohorts in the immediate aftermath of injury and this was accompanied by a significant reduction in the levels of GSN and ***:The post-traumatic increase in circulating cfDNA that occurs following extracranial trauma and TbI

关键词： Cell-free DNA Deoxyribonuclease Extracellular actin scavenging system Pre-hospital Trauma

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石墨表面研究:浸渍动力学

炭素 1979年第3期 19-25页

作者： S·S·bARTON ,b·H·harrison ,吴守谦

在水、甲酸和苯中测定经过直到1000℃排气处理的石墨的浸渍热。在浸渍所允许的与解吸种类有关的变化下,排气期间,氧的复合物的脱除可用质谱仪系统定量监测。

关键词：石墨表面表面积氧化物表面排气温度石英管球管动力学