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Vibration induced flow in hoppers:DEM 2D poly.on model

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Particuology 2008年第6期6卷 455-466页

作者： Feras y. Fraige Paul A. Langston Andrew j. Matchett j.hn Dodds Faculty.of Mining and Environmental Engineering Al-Hussein Bin Talal University Jordan Chemical and Environmental Engineering Nottingham University University Park Chemical Engineering University of Teesside Centre RAPSODEE Ecole Des Mines

A two-dimensional discrete element model （DEM） simulation of cohesive poly.onal particles has been developed to assess the benefit of point source vibration to induce flow in wedge-shaped hoppers. The particle-particle interaction model used is based on a multi-contact principle. The first part of the study.investigated particle discharge under gravity.without vibration to determine the critical orifice size （Bc） to j.st sustain flow as a function of particle shape. It is shown that poly.onal-shaped particles need a larger orifice than circular particles. It is also shown that Bc decreases as the number of particle vertices increases. Addition of circular particles promotes flow of poly.ons in a linear manner. The second part of the study.showed that vibration could enhance flow, effectively.reducing Bc. The model demonstrated the importance of vibrator location （height）, consistent with previous continuum model results, and vibration amplitude in enhancing flow.

关键词： Bulk solids Vibration DEM Hoppers Materials handling Poly.on

基于MRI的影像组学模型预测保乳术后乳腺癌病人手术切缘状态并推断肿瘤免疫微环境：一项多中心验证研究

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国际医学放射学杂志 2024年第3期 374-375页

作者： j.Ma K.Chen S.Li L.Zhu y.y. j.Li 梁媛

摘要目的术前准确评估保乳手术切缘阳性的风险，有助于制定手术计划。该项多中心验证研究开发了一种基于MRI的影像组学模型来预测手术切缘状态。方法回顾性

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Laser Assisted Fabrication for Controlled Single-Walled Carbon Nanotube Sy.thesis and Processing(Invited Paper)

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中国激光 2009年第12期36卷 3125-3132页

作者： W. Xiong y. Gao M. Mahj.uri-Samani y. S. Zhou M. Mitchell j. B. Park y. F. Lu Department of Electrical Engineering University of Nebraska-Lincoln

Although significant progress has been made in large scale and high quality.single-walled carbon nanotube(SWNT) sy.thesis,the fabrication of SWNT-based functional devices still faces many.challenges due to the lack of good methods to precisely.control over SWNTs growth location,orientation,alignment,and electronic ***,development of practical methods for well-controlled SWNT-based device fabrication has drawn great interests from both academics and *** to numerous advantages,laser-based techniques are applied in controlled fabrication of SWNT *** this paper,we first introduce the laser assisted chemical vapor deposition(LCVD) process,and then different aspects of controllability.in device fabrication are described in three sections: 1) location and orientation control of SWNT channels integration using optical near-field effects;2) alignment control of SWNTs array. using electrical biasing polarities;3) SWNTs electronic property.control using laser-induced breakdown *** experimental results show that well-organized individual SWNT channels or array. with location,orientation,alignment,and electronic property.control can be achieved through laser assisted fabrication process,which is a promising solution for the fabrication of future SWNT-based devices.

关键词：碳纳米管纳米材料光学技术生长位置

Ultrasonic solidification mechanism and optimized application performances of ternary.Mg_(71.5)Zn_(26.1)y.(2.4) alloy

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j.urnal of Magnesium and Alloy. 2023年第10期11卷 3829-3839页

作者： y.j.Hu j.y.Wang W.Zhai B.Wei School of Phy.ical Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

One dimensional(1D) and three dimensional(3D) ultrasound sources were applied to the solidification process of Mg_(71.5)Zn_(26.1)y.(2.4) *** acoustic spectra were in-situ measured, based on which the cavitation intensities and dy.amic solidification mechanism were further investigated. With the increase of ultrasonic dimension and amplitude, the primary.Mg_(3)Zn_(6)y.phase was significantly.refined from petals to nearly.pentagonal shape. The sound field measurements showed that the transient cavitation play.d a decisive role in generating a high local undercooling, which facilitated the formation of icosahedral clusters and promoted the nucleation of primary.Mg_(3)Zn_(6)y.phase. The morphological transition of(α-Mg+Mg_(3)Zn_(6)y. eutectic from lamellar to anomalous structure occurred under 3D ultrasonic condition. The stable cavitation took the main responsibility.because the high pressure excited by.nonlinearly.oscillating bubbles induced the preferential nucleation of α-Mg phase rather than Mg_(3)Zn_(6)y.phase. As compared with its static values, the tensile strength and compression plasticity.of this alloy.were increased by.the factors of 1.9 and 2.1, and its corrosion resistance was also improved with the corrosion current density.decreased by.one order of magnitude.

关键词： Three dimensional ultrasounds Quasicry.talline Mg_(3)Zn_(6)y.phase Anomalous eutectic Mechanical performances Corrosion resistance

Impact of temporal modulations on laser-induced damage of fused silica at 351 nm

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High Power Laser Science and Engineering 2023年第2期11卷 1-9页

作者： C.Bouy.r R.Parreault N.Roquin j.-y.Natoli L.Lamaignère CEA CESTA Le BarpFrance Aix-Marseille Univ CNRSCentrale MarseilleInstitut FresnelMarseilleFrance

Laser-induced damage(LID)on high-power laser facilities is one of the limiting factors for the increase in power and *** confinement fusion(ICF)facilities such as Laser Mégaj.ule or the National Ignition Facility.use spectral broadening of the laser pulse that may.induce power modulations because of frequency.modulation to amplitude modulation *** this paper,we study.the impact of low and fast power modulations of laser pulses both experimentally.and *** MELBA experimental testbed was used to shape a wide variety.of laser pulses and to study.their impact on LID.A 1D Lagrangian hy.rody.amic code was used to understand the impact of different power profiles on LID.

关键词： fused silica high-power laser laser diagnostics laser-induced damage

A case of pseudomembranous colitis associated with rifampicin

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Chinese Medical j.urnal 1998年第1期111卷 90-91页

作者： L. y. Chan Francis K. L. Chan j.seph j. y. Sung Department of Medicine Prince of Wales Hospital The Chinese University of Hong Kong Hong Kong China

ＡｃａｓｅｏｆｐｓｅｕｄｏｍｅｍｂｒａｎｏｕｓｃｏｌｉｔｉｓａｓｏｃｉａｔｅｄｗｉｔｈｒｉｆａｍｐｉｃｉｎＬ．Ｙ．Ｃｈａｎ，ＦｒａｎｃｉｓＫ．Ｌ．ＣｈａｎａｎｄＪｏｓｅｐｈＪ．Ｙ．ＳｕｎｇＤｅｐａｒｔｍｅｎｔｏｆＭｅ... 详细信息

ＡｃａｓｅｏｆｐｓｅｕｄｏｍｅｍｂｒａｎｏｕｓｃｏｌｉｔｉｓａｓｏｃｉａｔｅｄｗｉｔｈｒｉｆａｍｐｉｃｉｎＬ．Ｙ．Ｃｈａｎ，ＦｒａｎｃｉｓＫ．Ｌ．ＣｈａｎａｎｄＪｏｓｅｐｈＪ．Ｙ．ＳｕｎｇＤｅｐａｒｔｍｅｎｔｏｆＭｅｄｉｃｉｎｅ，ＰｒｉｎｃｅｏｆＷａ...

关键词： case A case of pseudomembranous colitis associated with rifampicin

重症监护室护士限制治疗努力的能力:整合性综述

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International j.urnal of Nursing Sciences 2024年第1期11卷 143-154,I0003页

作者： Elvia R.Lopez-Panza Vanessa C.Pacheco-Roy. Kelly.j.Fernandez-Ahumada Diana C.Díaz-Mass María y.Exposito-Concepcion Elizabeth Villarreal-Cantillo Cesar I.Aviles Gonzalez Nursing Department Universidad del NorteBarranquillaColombia Nursing Program Faculty of Health SciencesUniversidad Popular del CesarValleduparColombia Clínica Valledupar ValleduparColombia Hospital Universidad del Norte SoledadColombia Department of Medical Sciences and Public Health University of CagliariCittadella Universitaria di MonserratoCagliariItaly

目的在重症监护病房(IntensiveCareUnit,ICU),护土难免会遇到需要限制治疗努力(limiting therapeutie efort,LTE)的患者,尽管多数护士还缺乏为这些临终患者及其家庭提供支持的准备。本综述旨在描述ICU护士在LTE中需要具备的能力。方法对... 详细信息

目的在重症监护病房(IntensiveCareUnit,ICU),护土难免会遇到需要限制治疗努力(limiting therapeutie efort,LTE)的患者,尽管多数护士还缺乏为这些临终患者及其家庭提供支持的准备。本综述旨在描述ICU护士在LTE中需要具备的能力。方法对2010年--2023年发表的文献进行综述。系统检索了5个数据库:Medline、Wiley.Online Library.SciELO、ScienceDirect和Web of Science。使用关键评估项目工具西班牙语版(Critical Appraisal Skills Programme in Spanish,CASPe)作为评判性阅读工具。使用牛津循证医学中心(Center for Evidence-Based Medicine.,CEBM)评估工具确定证据级别和推荐强度。结果共纳入25篇文献。ICU护士LTE护理的能力包括对患者的直接护理、以家庭为中心的护理以及护士在团队中的作用。该综述确定了3个类别的能力:作为患者、家庭与跨学科团队之间维护者的能力,在LTE方面的决策能力,在患者生命末期治疗和护理干预的能力。结论ICU护士在LTE方面需要具备相应的能力,这对患者的生活质量死亡尊严以及患者家庭应对悲伤的全面支持至关重要。

关键词：重症监护家庭支持重症监护病房护士的作用安宁疗护专业能力

云微物理参数化的改进及其对川藏铁路沿线降水的模拟优势

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中国科学：地球科学 2024年第3期54卷 874-891页

作者：徐晓齐衡志炜李跃清王顺久李建王元陈景华张佩文陆春松南京气象科技创新研究院中国气象局交通气象重点开放实验室南京210041 中国气象局成都高原气象研究所高原与盆地暴雨旱涝灾害四川省重点实验室成都610072 中国气象科学研究院灾害天气国家重点实验室北京100081 兰州大学西部生态安全省部共建协同创新中心兰州730000 南京信息工程大学中国气象局气溶胶与云降水重点开放实验室/气象灾害预报预警与评估协同创新中心南京210044

川藏铁路是我国铁路网的重要组成部分,该区域山洪、滑坡等地质灾害多发,而降水是诱发这些灾害的重要原因,因此该区域降水的准确模拟是至关重要的.本文改进了西南区域业务预报模式云微物理方案中不确定性较大的物理过程,包括云滴活化、... 详细信息

川藏铁路是我国铁路网的重要组成部分,该区域山洪、滑坡等地质灾害多发,而降水是诱发这些灾害的重要原因,因此该区域降水的准确模拟是至关重要的.本文改进了西南区域业务预报模式云微物理方案中不确定性较大的物理过程,包括云滴活化、云水自动转化、云雨碰并和混合蒸发过程.原方案中,不同大小的云水含量对应着相同的云滴浓度,与实际不符,造成云滴尺度过大,相关物理过程速率(比如云水自动转化率)过快,导致降水高估.新方案克服了云滴尺度过大的问题,云水自动转化和云雨碰并过程均与随机收集方程更为接近,云滴蒸发机制更符合云中实际物理过程.基于新旧方案,模拟了川藏铁路沿线2021年汛期的多次降水过程,利用地面观测和卫星反演资料,评估了模拟结果.新方案对云物理量的模拟变得更为合理,使原方案对液水路径和液滴半径的模拟偏差从2倍减少到1倍以内,并显著缓解了原方案对降水强度和范围的高估情况,降水的平均均方根误差减小22%.本文所得结果能够为提高模式在该区域预报降水和灾害防控能力提供科学参考.

关键词：川藏铁路云微物理降水模式改进

青藏高原及其周边泥盆纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 1058-1090页

作者：郄文昆梁昆郭文高彪宋俊俊陈波黄璞乔丽徐洪河陈吉涛孙语聪张以春中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学南京学院南京211135

青藏高原及其周边泥盆系分布广泛、类型多样、化石丰富,记录着北半球古亚洲洋的持续消减和南半球原特提斯洋向古特提斯洋转变的关键过程,对阐明这一时期的全球古地理格局、板块运动和生物多样性变化具有重要意义.南天山(洋)缝合带和龙木... 详细信息

青藏高原及其周边泥盆系分布广泛、类型多样、化石丰富,记录着北半球古亚洲洋的持续消减和南半球原特提斯洋向古特提斯洋转变的关键过程,对阐明这一时期的全球古地理格局、板块运动和生物多样性变化具有重要意义.南天山(洋)缝合带和龙木错-双湖-昌宁-孟连(洋)缝合带两侧的地块分属不同沉积体系和生物古地理区系,指示该洋盆具有显著的构造古地理分隔意义,分别代表了古亚洲洋和古特提斯洋的主支洋盆,以此为界泥盆系可以划分为天山型、特提斯型和冈瓦纳型三种类型.本文主要基于近年来青藏高原及其邻区泥盆纪地层古生物的研究进展,分别提供最新的综合地层格架,并结合沉积物源分析和生物群特征对比进行古地理重建,为探讨青藏高原及其邻区各个块体的早期地质演化及其动力学机制奠定基础.基于碎屑锆石物源分析和生物古地理研究,特提斯喜马拉雅带、保山地块、南羌塘地块、北羌塘地块、思茅地块、腾冲地块和华南板块沉积物源与印度板块具有亲缘性,而拉萨地块与澳大利亚板块具有亲缘性,且可能位于华南板块与澳大利亚板块之间.早泥盆世埃姆斯期,华南板块可能已经从冈瓦纳大陆北缘裂解出来,代表着金沙江-哀牢山洋的打开.中泥盆世,古特提斯洋洋中脊快速扩张,对应着全球海平面上升、碳酸盐岩台地的广泛分布和泥盆纪海水锶同位素的最低值.晚泥盆世古特提斯洋已达到相当规模,最终导致古特提斯缝合带中晚泥盆世放射虫硅质岩大量产出.

关键词：泥盆系古特提斯洋综合地层生物群物源分析古地理