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Ultrafast epitaxial growth of metre-sized single-crystal graphene on industrial Cu foil 被引量:46
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作者 Xiaozhi Xu Zhihong Zhang +20 位作者 Jichen Dong Ding Yi Jingjing Niu Muhong Wu Li Lin Rongkang Yin Mingqiang Li Jingyuan Zhou Shaoxin Wang Junliang Sun Xiaojie Duan Peng Gao Ying Jiang Xiaosong Wu Hailin Peng rodney S. Ruoff Zhongfan Liu Dapeng Yu Enge Wang Feng Ding Kaihui Liu 《Science Bulletin》 SCIE EI CAS CSCD 2017年第15期1074-1080,共7页
A foundation of the modern technology that uses single-crystal silicon has been the growth of highquality single-crystal Si ingots with diameters up to 12 inches or larger. For many applications of graphene, large-are... A foundation of the modern technology that uses single-crystal silicon has been the growth of highquality single-crystal Si ingots with diameters up to 12 inches or larger. For many applications of graphene, large-area high-quality(ideally of single-crystal) material will be enabling. Since the first growth on copper foil a decade ago, inch-sized single-crystal graphene has been achieved. We present here the growth, in 20 min, of a graphene film of(5 ×50) cm^2 dimension with >99% ultra-highly oriented grains.This growth was achieved by:(1) synthesis of metre-sized single-crystal Cu(1 1 1) foil as substrate;(2)epitaxial growth of graphene islands on the Cu(1 1 1) surface;(3) seamless merging of such graphene islands into a graphene film with high single crystallinity and(4) the ultrafast growth of graphene film.These achievements were realized by a temperature-gradient-driven annealing technique to produce single-crystal Cu(1 1 1) from industrial polycrystalline Cu foil and the marvellous effects of a continuous oxygen supply from an adjacent oxide. The as-synthesized graphene film, with very few misoriented grains(if any), has a mobility up to ~23,000 cm^2 V^(-1)s^(-1)at 4 K and room temperature sheet resistance of ~230 Ω/□. It is very likely that this approach can be scaled up to achieve exceptionally large and high-quality graphene films with single crystallinity, and thus realize various industrial-level applications at a low cost. 展开更多
关键词 Single-crystal Industrial Cu Graphene Ultrafast Epitaxial
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珠江三角洲沉积物的岩石磁学性质及其环境意义 被引量:22
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作者 杨小强 rodney Grapes +1 位作者 周厚云 阳杰 《中国科学(D辑)》 CSCD 北大核心 2007年第11期1493-1503,共11页
选取珠江三角洲区域位于广州番禺的PD钻孔进行沉积物岩石磁学和环境磁学记录的研究.岩石磁学实验表明钻孔大部分沉积物以低矫顽力的磁铁矿类矿物为主要控磁矿物,但仍存在少量铁硫化物.在有机质丰富的灰黑色黏土沉积中,铁硫化物含量增加... 选取珠江三角洲区域位于广州番禺的PD钻孔进行沉积物岩石磁学和环境磁学记录的研究.岩石磁学实验表明钻孔大部分沉积物以低矫顽力的磁铁矿类矿物为主要控磁矿物,但仍存在少量铁硫化物.在有机质丰富的灰黑色黏土沉积中,铁硫化物含量增加,成为影响沉积物磁性特征的主要矿物,标志着海退后富含有机质而缺氧的沼泽环境.以赤铁矿和针铁矿类矿物为主要控磁矿物的花斑黏土,表明了一个较长时期的暴露风化过程,代表着沉积间断.在以磁铁矿类矿物作为主要载磁矿物的沉积物中,磁铁矿浓度及粒度的变化主导磁化率(κ)、饱和等温剩磁(SIRM)等环境磁学参数的变化,SIRM/κ和χarm/SIRM的大小旋回响应于海平面的升-降过程,它们的高值反映了磁性矿物粒度变细、海平面上升.在沉积学分析的基础上,根据环境磁学参数截然不同的变化规律,结合微体古生物数据,将珠江三角洲沉积物代表的环境分为两次显著的海平面上升-下降旋回,晚更新世和全新世的海侵又包含若干个比较明显的次级海平面波动过程. 展开更多
关键词 珠江三角洲 岩石磁学 海平面变化 沉积物 环境意义
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项目管理理论及其架构 被引量:17
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作者 rodney Turner 杨伟 杨玉武 《项目管理技术》 2006年第10期16-22,共7页
一种观点认为缺乏全面的理论是阻碍项目管理被认可为一门管理学科的因素,现存的被系统观点所统治的项目管理理论更多地被视做工程学的分支,而不是管理学。更进一步,现存的理论是建立在大量源自经验证据的假设基础上的,这使得最终产... 一种观点认为缺乏全面的理论是阻碍项目管理被认可为一门管理学科的因素,现存的被系统观点所统治的项目管理理论更多地被视做工程学的分支,而不是管理学。更进一步,现存的理论是建立在大量源自经验证据的假设基础上的,这使得最终产生的理论似乎仅仅是建立在假设基础上的经验证据。这些假设使用了复杂的需要进一步界定的概念,这又使得项目管理理论似乎仅仅是一些定义。在这篇文章中,作者提出一套建立在五个简单的、自然的前提之上的关于项目管理的理论。这些前提不需要假设,所使用的简单的、自然的概念也不需要进一步界定(或者,另外一种情况是概念是由前面的前提得出的)。 展开更多
关键词 项目管理理论 项目价值 项目治理 利益相关方
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^(18)F-FDG PET/CT显像在鼻咽癌分期与疗效监测中的临床应用价值 被引量:19
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作者 王国慧 Eddie W. F. Lau +4 位作者 Ramdave Shakher David S. Binns Annette Hogg Elizabeth Drummond rodney J. Hicks 《癌症》 SCIE CAS CSCD 北大核心 2007年第6期638-642,共5页
背景与目的:18F-脱氧葡萄糖(fluorine-18 fluorodeoxyglucose,18F-FDG)PET/CT显像可明显提高肺癌、食管癌等多种肿瘤的诊断、分期与疗效监测的准确性,有助于更准确地制定治疗方案。本研究探讨全身18F-FDG PET/CT显像在鼻咽癌首次分期、... 背景与目的:18F-脱氧葡萄糖(fluorine-18 fluorodeoxyglucose,18F-FDG)PET/CT显像可明显提高肺癌、食管癌等多种肿瘤的诊断、分期与疗效监测的准确性,有助于更准确地制定治疗方案。本研究探讨全身18F-FDG PET/CT显像在鼻咽癌首次分期、再分期及疗效监测中的临床应用价值。方法:回顾性分析澳大利亚Peter MacCallum肿瘤中心2002年2月至2005年12月43例鼻咽癌患者的18F-FDG PET/CT全身扫描报告,根据临床资料、病理结果及临床随访结果,计算18F-FDG PET/CT与传统影像学检查CT、MRI的准确性、特异性、灵敏度、阳性预测值与阴性预测值,并对结果进行比较和分析。结果:18F-FDG PET/CT诊断鼻咽癌总的准确率、敏感性、特异性、阳性预测值与阴性预测值分别为95.3%、100.0%、85.7%、93.8%、100.0%,传统影像学检查CT、MRI分别为65.5%、79.4%、64.7%、81.8%、57.9%。18F-FDGPET/CT诊断结果使2例首次分期、7例再分期患者治疗方案得到改变,并影响1例首次分期和3例再分期患者治疗方案的制定;在疗效监测组中,指导医生修改治疗方案共11例(其中5例为原则性的修改)。18F-FDG PET/CT检测到2例第二原发肿瘤,1例是甲状腺癌,1例是低度恶性胃癌。结论:18F-FDG PET/CT全身显像对鼻咽癌N、M分期与疗效监测的临床作用可能优于CT、MR检查。 展开更多
关键词 鼻咽肿瘤 肿瘤分期 体层摄影术 发射型计算机 体层摄影术 X线计算机 脱氧葡萄糖 诊断 疗效监测
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Newborn screening for Duchenne muscular dystrophy in China: follow-up diagnosis and subsequent treatment 被引量:17
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作者 Qing Ke Zheng-Yan Zhao +11 位作者 Robert Griggs Veronica Wiley Anne Connolly Jennifer Kwon Ming Qi Daniel Sheehan Emma Ciafaloni R rodney Howell Petra Furu Peter Sazani Arvind Narayana Michele Gatheridge 《World Journal of Pediatrics》 SCIE CAS CSCD 2017年第3期197-201,共5页
Background:Newborn screening for Duchenne muscular dystrophy (DMD) is currently being initiated in Zhejiang Province,China and is under consideration in other countries,including the United States.As China begins to i... Background:Newborn screening for Duchenne muscular dystrophy (DMD) is currently being initiated in Zhejiang Province,China and is under consideration in other countries,including the United States.As China begins to implement DMD newborn screening (DMD-NBS),there is ongoing discussion regarding the steps forward for follow up care of positively identified patients as well as false positive and false negative results.Data sources:Relevant papers related to DMD-NBS,and NBS in China were reviewed in PubMed.Results:The current state of DMD-NBS is discussed,along with the steps needed to effectively screen infants for this disease in China,recommendations for establishment of follow up care in patients with positive and negative screens,and measurement of patient outcomes.Conclusions:Zhejiang Province,China is ready to implement DMD-NBS.Future challenges that exist for this program,and other countries,include the ability to track patients,assist with access to care,and ensure adequate follow-up care according to evidence-based guidelines.In addition,China's large rural population,lack of specialty providers,and difficulty in educating patients regarding the benefits of treatment create challenges that will need to be addressed. 展开更多
关键词 Duchene MUSCULAR DYSTROPHY NEUROLOGY NEUROMUSCULAR disorders NEWBORN screening
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Facile,Noncovalent Decoration of Graphene Oxide Sheets with Nanocrystals 被引量:13
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作者 Ganhua Lu Shun Mao +2 位作者 Sungjin Park rodney S.Ruoff Junhong Chen 《Nano Research》 SCIE EI CSCD 2009年第3期192-200,共9页
Facile dry decoration of graphene oxide sheets with aerosol Ag nanocrystals synthesized from an arc plasma source has been demonstrated using an electrostatic force directed assembly technique at room temperature.The ... Facile dry decoration of graphene oxide sheets with aerosol Ag nanocrystals synthesized from an arc plasma source has been demonstrated using an electrostatic force directed assembly technique at room temperature.The Ag nanocrystal-graphene oxide hybrid structure was characterized by transmission electron microscopy(TEM)and selected area diffraction.The ripening of Ag nanocrystals on a graphene oxide sheet was studied by consecutive TEM imaging of the same region on a sample after heating in Ar at elevated temperatures of 100°C,200°C,and 300°C.The average size of Ag nanocrystals increased and the number density decreased after the annealing process.In particular,migration and coalescence of Ag nanocrystals were observed at a temperature as low as 100°C,suggesting a van der Waals interaction between the Ag nanocrystal and the graphene oxide sheet.The availability of affordable graphene-nanocrystal structures and their fundamental properties will open up new opportunities for nanoscience and nanotechnology and accelerate their applications. 展开更多
关键词 Graphene oxide silver nanocrystals hybrid nanostructures nanocrystal ripening
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Magnetic properties of sediments from the Pearl River Delta,South China:Paleoenvironmental implications 被引量:13
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作者 rodney GRAPES 《Science China Earth Sciences》 SCIE EI CAS 2008年第1期56-66,共11页
Magnetic parameters and their environmental implications of sediments in a core (PD) from the Pearl River Delta, South China, indicate that ferrimagnetic minerals with low coercivity, such as magnetite, dominate the m... Magnetic parameters and their environmental implications of sediments in a core (PD) from the Pearl River Delta, South China, indicate that ferrimagnetic minerals with low coercivity, such as magnetite, dominate the magnetic properties although small amounts of Fe-sulphides occur. The fraction of Fe-sulphides increases and becomes the dominant minerals determining the magnetic characteristics in grey-black organic-rich clay horizons, indicating an anoxic, sulphate-reducing swamp environment resulting from a marine regression. In the "Huaban clay" , hard magnetic minerals, such as hematite and goethite, largely control the magnetic properties of the sediments and imply a long period of exposure and weathering. Where magnetite is the main magnetic mineral, its fraction and grain size determine properties such as magnetic susceptibility (κ ) and saturation isothermal remanent magnetization (SIRM). Ratios of SIRM/κ and χarm/SIRM reflect changes in sea level with high SIRM/κ and χarm/SIRM correlating with a smaller magnetic mineral grain size and rising sea level. Based on downcore variations of these environmental magnetic parameters along with sediment characteristics and microfauna, the sedimentary environment of the Pearl River Delta area can be divided into two main cycles of transgression and regression during the late Pleistocene and Holocene with more sub-cycles of sea level fluctuation during each transgression. 展开更多
关键词 the PEARL River Delta rock MAGNETIC properties environmental MAGNETIC signatures SEDIMENTARY environment SEA-LEVEL change
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美国科学信息研究所对完善ISI数据库选刊标准中有关中国期刊文献收录方针的进展报告与建议 被引量:12
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作者 rodney Chonka 郑晓南 《中国科技期刊研究》 CSSCI 2000年第1期8-11,共4页
目前,美国科学信息研究所(ISI)数据库收录了60种中国期刊(不包括台湾省期刊)为刊源,其中13种被 SCI 收录;虽然中国期刊在 ISI 数据库中所占比例很小,但近两年其刊源数量有明显增长。科技期刊的研究质量是办刊之本,但各国研究者在检索本... 目前,美国科学信息研究所(ISI)数据库收录了60种中国期刊(不包括台湾省期刊)为刊源,其中13种被 SCI 收录;虽然中国期刊在 ISI 数据库中所占比例很小,但近两年其刊源数量有明显增长。科技期刊的研究质量是办刊之本,但各国研究者在检索本专业最新资料时,文献目录的信息也十分重要。ISI 数据库是唯一包括所有论文参考文献的文摘检索服务系统,它所摘引的参考文献给专业研究人员带来很大的帮助。ISI 为了给读者提供最完善可靠的文献目录信息,将期刊按国际规范编排,附上所有英文参考文献,不仅提高了文献检索率还标明了所引刊物,这在列举引文资料时非常重要。近年来,越来越多的中国文献也开始列出英文参考文献,这对于中国期刊的发展有重要意义,文献标准化是提供准确的期刊引文分析的关键。还有期刊的刊名必须清楚,中文刊名、英译名、汉语拼音名、拉丁文刊名、各种情况的英文版本名应有所区分,标注得当,目的是尽量给检索系统提供最清楚、准确的信息,以免与同类刊物混淆。本文介绍了 ISI 数据库收录期刊的方针并推荐一些收录期刊的可取经验,目的是为了使更多的中国学术期刊进入国际科技出版的主流并真正被世界科学家认同。 展开更多
关键词 科技期刊 ISI 数据库 选刊 标准 收录方针
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华南花岗岩暗色微粒包体成因研究 被引量:13
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作者 彭卓伦 rodney Grapes +1 位作者 庄文明 张献河 《地学前缘》 EI CAS CSCD 北大核心 2011年第1期82-88,共7页
通过对暗色微粒包体的空间分布和形态特征以及包体矿物学、显微结构和岩石化学组成等方面的研究成果,在花岗岩"原地重熔"成因模型的基础上,建立了包体演化与熔渣演化的关系模型,证实包体的前身是捕虏体,后者代表从盖层落入岩... 通过对暗色微粒包体的空间分布和形态特征以及包体矿物学、显微结构和岩石化学组成等方面的研究成果,在花岗岩"原地重熔"成因模型的基础上,建立了包体演化与熔渣演化的关系模型,证实包体的前身是捕虏体,后者代表从盖层落入岩浆中的岩块,包体则是岩块部分熔融后的残余物。不同类型、不同形态、不同基性度的包体,代表了岩石原地熔融过程中不同阶段的产物,富云包体反映了熔渣演化的最后阶段,在此基础上的进一步熔融即与寄主岩浆混成一体,完成了从岩石到岩浆的整个演化过程。 展开更多
关键词 花岗岩 原地重熔 暗色微粒包体 残余熔渣
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Ultrathin monolithic 3D printed optical coherence tomography endoscopy for preclinical and clinical use 被引量:12
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作者 Jiawen Li Simon Thiele +8 位作者 Bryden C.Quirk rodney W.Kirk Johan W.Verjans Emma Akers Christina A.Bursill Stephen J.Nicholls Alois M.Herkommer Harald Giessen Robert A.McLaughlin 《Light(Science & Applications)》 SCIE EI CAS CSCD 2020年第1期753-762,共10页
Preclinical and clinical diagnostics increasingly rely on techniques to visualize internal organs at high resolution via endoscopes.Miniaturized endoscopic probes are necessary for imaging small luminal or delicate or... Preclinical and clinical diagnostics increasingly rely on techniques to visualize internal organs at high resolution via endoscopes.Miniaturized endoscopic probes are necessary for imaging small luminal or delicate organs without causing trauma to tissue.However,current fabrication methods limit the imaging performance of highly miniaturized probes,restricting their widespread application.To overcome this limitation,we developed a novel ultrathin probe fabrication technique that utilizes 3D microprinting to reliably create side-facing freeform micro-optics(<130μm diameter)on single-mode fibers.Using this technique,we built a fully functional ultrathin aberration-corrected optical coherence tomography probe.This is the smallest freeform 3D imaging probe yet reported,with a diameter of 0.457 mm,including the catheter sheath.We demonstrated image quality and mechanical flexibility by imaging atherosclerotic human and mouse arteries.The ability to provide microstructural information with the smallest optical coherence tomography catheter opens a gateway for novel minimally invasive applications in disease. 展开更多
关键词 smallest utilize OVERCOME
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A six-year descriptive epidemiological study of human coronavirus infections in hospitalized patients in Hong Kong 被引量:11
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作者 Cyril C.Y.Yip Carol S.F.Lam +8 位作者 Hayes K.H.Luk Emily Y.M.Wong rodney A.Lee Lok-Yee So Kwok-Hung Chan Vincent C.C.Cheng Kwok-Yung Yuen Patrick C.Y.Woo Susanna K.P.Lau 《Virologica Sinica》 SCIE CAS CSCD 2016年第1期41-48,共8页
We conducted a six-year epidemiological study on human coronaviruses(HCoVs) circulating in Hong Kong, using 8275 nasopharyngeal samples from patients with acute respiratory tract infections. HCoVs were detected in 7... We conducted a six-year epidemiological study on human coronaviruses(HCoVs) circulating in Hong Kong, using 8275 nasopharyngeal samples from patients with acute respiratory tract infections. HCoVs were detected in 77(0.93%) of the samples by a pan-HCoV RT-PCR assay. The most frequently detected HCoV species was HCoV-OC43(0.58%), followed by HCoV-229E(0.15%),HCoV-HKU1(0.13%) and HCoV-NL63(0.07%). HCoVs were detected throughout the study period(September 2008–August 2014), with the highest detection rate from September 2010 to August2011(22/1500, 1.47%). Different seasonal patterns of each HCoV species in Hong Kong were noted.HCoV-OC43 was predominant in the fall and winter, whereas HCoV-HKU1 showed peak activity in winter, with a few cases occurred in spring and summer. HCoV-229 E mainly occurred in winter and spring, while HCoV-NL63 was predominant in summer and autumn. HCoVs most commonly infect the elderly and young children, with median age of 79.5 years(range, 22 days to 95 years).Intriguingly, the detection rate of HCoV-OC43 in the age group of &gt; 80 years(26/2380, 1.09%) was significantly higher than that in the age group of 0–10 years(12/2529, 0.47%)(P 〈 0.05). These data provides new insight into the epidemiology of coronaviruses. 展开更多
关键词 epidemiology human coronaviruses respiratory tract infections
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壳内熔融与大陆造山--中山大学地质学系成立90周年暨陈国达院士诞辰102周年纪念 被引量:9
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作者 陈国能 陈震 +12 位作者 陈雄 丁汝鑫 彭卓伦 rodney Grapes 张珂 王岳军 娄峰 沈文杰 郑义 张俊浩 邱惟 许清燕 王勇 《大地构造与成矿学》 EI CAS CSCD 北大核心 2015年第3期383-390,共8页
本文将造山作用分为地槽褶皱造山和地台(克拉通)活化造山两种类型,并认为两者均起因于板块的汇聚过程。地槽造山是洋壳向陆壳的转换过程,其标志是地槽沉积物初次熔融形成的、以TTG为主的"不成熟花岗岩"产生。板块俯冲过程的... 本文将造山作用分为地槽褶皱造山和地台(克拉通)活化造山两种类型,并认为两者均起因于板块的汇聚过程。地槽造山是洋壳向陆壳的转换过程,其标志是地槽沉积物初次熔融形成的、以TTG为主的"不成熟花岗岩"产生。板块俯冲过程的能量转换,导致大陆岩石圈内能升高,包括TTG在内的基底地槽构造层的再次熔融(重熔),产生再生或重熔岩浆形成活化造山期的"成熟花岗岩";壳内重熔岩浆层形成和增厚最终导致大陆克拉通发生大规模压缩变形(活化造山)。造山作用的多幕性和花岗岩活动多期性,以及上老下新的花岗岩"层序",被认为主要与板块俯冲过程的能量转换速度有关。 展开更多
关键词 褶皱造山 活化造山 壳内熔融 花岗岩 板块汇聚 熔融大地构造
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一种新的IPDiffServoverOBS网络体系结构及性能分析(英文) 被引量:9
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作者 隆克平 rodney S.Tucker 王重钢 《重庆邮电学院学报(自然科学版)》 2004年第2期1-6,66,共7页
IPDiffServ已经被IETF标准化,并由于其实现简单和易于扩展被作为IPQoS的一种好的解决办法。提出了一种新的光突发交换网络支持IPDiffServ的网络体系结构,称为DS-OBS,并给出了网络结构、边缘节点和核心节点的功能模型、控制包格式、入口... IPDiffServ已经被IETF标准化,并由于其实现简单和易于扩展被作为IPQoS的一种好的解决办法。提出了一种新的光突发交换网络支持IPDiffServ的网络体系结构,称为DS-OBS,并给出了网络结构、边缘节点和核心节点的功能模型、控制包格式、入口节点的会聚算法和核心节点的调度算法。与目前基于offsettime的OBSQoS结构不同,提出结构的基本思想是:在入口边缘路由器执行业务区分的突发会聚,在核心节点对不同类的控制包执行不同的每一跳行为(PHB)处理,从而实现业务区分。仿真结果表明:提出的结构能在端到端延迟、吞吐量和IP分组丢失等对EF类、AF类和BE类提供很好的业务区分。 展开更多
关键词 IP服务质量 区分服务 每一跳行为 光突发交换 突发会聚
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基于无人机多光谱植被指数的生菜全氮含量预测
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作者 连炳瑞 李雅豪 +6 位作者 张静 李长青 杨小冬 王激清 邹国元 Thompson rodney 杨俊刚 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第8期2318-2325,共8页
我国露地蔬菜种植规模庞大,生产方式高度集约化,但过量施肥等导致的水氮利用效率低下的问题较为严重。为实现露地蔬菜规模化种植中精准施肥、高效生产的目标,以露地生菜为研究对象,设无氮(N0)、低氮(N1)、高氮(N2)三个处理,通过无人机... 我国露地蔬菜种植规模庞大,生产方式高度集约化,但过量施肥等导致的水氮利用效率低下的问题较为严重。为实现露地蔬菜规模化种植中精准施肥、高效生产的目标,以露地生菜为研究对象,设无氮(N0)、低氮(N1)、高氮(N2)三个处理,通过无人机搭载多光谱相机,建立3种多光谱植被指数(NDVI、RVI和SAVI)与生菜叶绿素、生物量、吸氮量、全氮含量数据集,并构建单生育期和多生育期氮素诊断模型。结果表明:(1)在莲座期和结球期,生菜各处理NDVI、RVI和SAVI值表现出随施氮量的增加而增大,但在收获期,N1处理达到最大值。(2)在生菜结球期,NDVI与生菜的产量、吸氮量、叶绿素均存在显著相关性,其中生菜全氮含量与叶绿素在p≤0.01水平下显著相关,相关系数(R)为0.51;综合生菜多生育期,NDVI值与生菜的产量、叶绿素、吸氮量和全氮含量均在p≤0.001水平下达到极显著相关,相关系数分别为0.85、0.82、0.81和0.71。(3)通过相应数据集拟合出指数、线性、对数和幂函数4种模型关系,建立生菜多生育期植株全氮最佳预测模型:全氮=16.52ln(NDVI)+73.514;应用生菜全氮估层模型反演基地生产田块,其平均相对误差为3.22%、RMSE=0.5566、NRMSE=0.0108,说明模型估算效果均较好,通过无人机多光谱遥感对蔬菜氮素诊断具有一定的可行性。 展开更多
关键词 露地生菜 无人机多光谱 NDVI 全氮 预测模型
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华南花岗岩暗色微粒包体矿物组成及微结构研究 被引量:8
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作者 彭卓伦 rodney Grapes +1 位作者 庄文明 张献河 《地学前缘》 EI CAS CSCD 北大核心 2011年第1期63-73,共11页
对来自华南多个花岗岩体的暗色微粒包体样品进行了系统的矿物组成和微结构研究,发现包体中不管是造岩矿物还是副矿物,均存在新、老两个不同世代;包体的微结构大部分情况下也不是"火成结构",而是以熔融结构为主,并且常多种结... 对来自华南多个花岗岩体的暗色微粒包体样品进行了系统的矿物组成和微结构研究,发现包体中不管是造岩矿物还是副矿物,均存在新、老两个不同世代;包体的微结构大部分情况下也不是"火成结构",而是以熔融结构为主,并且常多种结构共存,揭示包体是岩石部分熔融的残余物而并非来自岩浆的结晶。不同包体或同一包体从中心到边缘的矿物组成与微结构的差异,反映原岩部分熔融程度的不同,揭示其处于不同的演化阶段。 展开更多
关键词 花岗岩 暗色微粒包体 矿物组成 微结构
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Effect of music on patients undergoing outpatient colonoscopy 被引量:8
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作者 Matthew L Bechtold rodney A Perez +1 位作者 Srinivas R Puli John B Marshall 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第45期7309-7312,共4页
AIM: To evaluate the effect of relaxing music during colonoscopy under low-dose conscious sedation, on patient satisfaction, scope insertion time and procedure duration, medication doses, and the perceived adequacy of... AIM: To evaluate the effect of relaxing music during colonoscopy under low-dose conscious sedation, on patient satisfaction, scope insertion time and procedure duration, medication doses, and the perceived adequacy of sedation and scope insertion difficulty on the part of the endoscopist. METHODS: One hundred and sixty-seven consecutive adult outpatients presenting for routine colonoscopy under low-dose conscious sedation were randomized to undergo their procedures either with music played during the procedure or no music played. RESULTS: There were no statistical differences between the two groups in terms of meperidine dose, midazolam dose, time to reach the cecum, total procedure time, endoscopist assessment of scope insertion difficulty, endoscopist assessment of adequacy of sedation, or the pain experience of the patients during their procedure. The music group did report significantly better overall procedure satisfaction as compared to the non music group on two of our three different scales. CONCLUSION: While music does not result in shortened procedure times, lower doses of sedative medications or perceived patient pain, the patients who have music playing during their procedures report modestly greater satisfaction with their procedures. 展开更多
关键词 COLONOSCOPY Gastrointestinal endoscopy MUSIC Music therapy Relaxation music
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Synthesis of Isotopically-Labeled Graphite Films by Cold-Wall Chemical Vapor Deposition and Electronic Properties of Graphene Obtained from Such Films 被引量:7
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作者 Weiwei Cai Richard D.Piner +7 位作者 Yanwu Zhu Xuesong Li Zhenbing Tan Herman Carlo Floresca Changli Yang Li Lu M.J.Kim rodney S.Ruoff 《Nano Research》 SCIE EI CSCD 2009年第11期851-856,共6页
We report the synthesis of isotopically-labeled graphite films on nickel substrates by using cold-wall chemical vapor deposition(CVD).During the synthesis,carbon from^(12)C-and^(13)C-methane was deposited on,and disso... We report the synthesis of isotopically-labeled graphite films on nickel substrates by using cold-wall chemical vapor deposition(CVD).During the synthesis,carbon from^(12)C-and^(13)C-methane was deposited on,and dissolved in,a nickel foil at high temperature,and a uniform graphite film was segregated from the nickel surface by cooling the sample to room temperature.Scanning and transmission electron microscopy,micro-Raman spectroscopy,and X-ray diffraction prove the presence of a graphite film.Monolayer graphene films obtained from such isotopically-labeled graphite films by mechanical methods have electron mobility values greater than 5000 cm^(2)·V^(-1)·s^(-1)at low temperatures.Furthermore,such films exhibit the half-integer quantum Hall effect over a wide temperature range from 2 K to 200 K,implying that the graphite grown by this cold-wall CVD approach has a quality as high as highly oriented pyrolytic graphite(HOPG).The results from transport measurements indicate that^(13)C-labeling does not significantly affect the electrical transport properties of graphene. 展开更多
关键词 Chemical vapor deposition(CVD) isotopically-labeled graphite GRAPHENE
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The impact of the Rural Minimum Living Standard Guarantee(Rural Dibao)Program on child nutrition outcomes 被引量:1
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作者 Dian Chen Xiangming Fang +3 位作者 Yu Chen Xiaodong Zheng Zhuo Chen rodney B.W.Smith 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期444-456,共13页
The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycle... The Rural Minimum Living Standard Guarantee(Rural Dibao)is an important unconditional cash transfer program to alleviate poverty in rural China.Despite the importance of children’s nutrition in breaking poverty cycles,little is known about the impact of Rural Dibao on child nutrition outcomes.Using China Family Panel Studies(CFPS),this paper examines the effects of Rural Dibao on child nutrition outcomes and investigates potential pathways and heterogeneous effects.We exploit propensity score matching and difference-in-differences techniques to evaluate the effects of the Rural Dibao program on child nutrition outcomes.Our results suggest that Rural Dibao significantly impacts the nutrition outcomes of children up to 15 years of age.Specifically,our results suggest that Rural Dibao improves child height-to-age z-scores by 1.05 standard deviations and lowers the probability of stunting by 11.9 percentage points.Additional analyses suggest that increased protein intake is the main pathway through which Rural Dibao participation contributes to better nutrition outcomes.We also find that the effect of the program is more pronounced among girls,children who are non-left-behind or live with highly educated mothers,and those from low-income families and poor areas.Our findings suggest that Rural Dibao participation helps improve child nutrition outcomes through improving diet quality. 展开更多
关键词 Rural Minimum Living Standard Guarantee NUTRITION height-to-age z-scores STUNTING rural China
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基于MRI和血流动力学仿真的主动脉缩窄计算机辅助诊断系统
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作者 史宇兵 Israel Valverde +1 位作者 Patricia V.Lawford D.rodney Hose 《中国医学物理学杂志》 CSCD 2023年第1期126-132,共7页
目前用于心脑血管系统疾病的计算机辅助诊断系统比较少,本研究基于参加欧盟FP7 euHeart项目所做的工作,以对主动脉缩窄的处理为例,介绍一个基于核磁共振成像(MRI)和血流动力学计算的心脑血管疾病计算机辅助诊断系统,对系统的结构、功能... 目前用于心脑血管系统疾病的计算机辅助诊断系统比较少,本研究基于参加欧盟FP7 euHeart项目所做的工作,以对主动脉缩窄的处理为例,介绍一个基于核磁共振成像(MRI)和血流动力学计算的心脑血管疾病计算机辅助诊断系统,对系统的结构、功能和工作流程进行详细描述。该系统以患者病变血管的MRI图像和在颈动脉和股动脉处测得的血压波形为输入信息,通过图像处理模块、生理数据处理模块、计算网格生成模块以及流体动力学计算模块对这些数据进行分析处理,输出跨缩窄段的压差以辅助评估对患者进行干预手术的必要性,并输出病变血管段的流速分布、剪切应力分布等血流状态信息用于估算血流异常对血管内皮以及血细胞造成潜在机械损伤的程度。以一个典型病例的处理结果为例,对所开发的系统进行初步测试,结果表明所开发的系统运行结果准确可靠。本系统对于开发其他心脑血管疾病计算机辅助诊断系统具有借鉴意义。 展开更多
关键词 心脑血管疾病 计算机辅助诊断系统 核磁共振成像 血流动力学计算 计算机仿真
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Utility Impact below Bridge or Culvert Soffit on Open Channel Flow
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作者 rodney McDermott Sarah Quinn 《Open Journal of Modern Hydrology》 2023年第4期193-210,共18页
The background to this research was a flooding incident that occurred in Bridgend, Co. Donegal, Ireland in August 2017. While several properties were flooded, a flooding case study of a single dwelling house adjacent ... The background to this research was a flooding incident that occurred in Bridgend, Co. Donegal, Ireland in August 2017. While several properties were flooded, a flooding case study of a single dwelling house adjacent to the Bridgend River at Riverdale, Bunamayne, Co. Donegal, Ireland is used herein. For this study the flooded site shall be referred to as the “Hegarty property”. A structure in the form of a stone arched culvert is located directly adjacent to the two-storey detached dwelling house on the Hegarty Property. While the culvert is referred to locally as a bridge, within this research the word culvert will be used in connection with the structure. The culvert has a concrete surrounded utility (watermain) crossing at a gradient below the culvert soffit on the upstream face of the structure. The utility obstructed flow through the culvert and contributed to the flooding event. Given the implication of climate change and the increased probability of more extreme flooding events, it was decided to explore the case study to ascertain the factors that contribute to flooding events when utilities are positioned at culvert or bridge structures. This work was completed to assist undergraduate students, researchers, and local authorities in a relatively unknown area of flood causation. 展开更多
关键词 UTILITY BRIDGE CULVERT Hydraulics FLOODING Climate Change & Open Channel Flow
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