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地球与环境 1986年第9期 34-41页

作者： k.j.fraser 徐步台浙江省地质科学研究所

一、引言最近五年,有些研究者已不采用两组分（地壳和亏损地幔）简单模式来解释幔源岩石中放射成因同位素的变化。大陆下地幔中捕虏体的 ∈;、∈;和Pb同位素比值变化很大,这种情况被认为是大陆岩石圈内古老地幔物质

关键词： Pb 西澳大利亚钾镁煌斑岩金云火山岩同位素金伯利岩角砾云母橄榄岩超基性岩 Nd Sr

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单分子结中的有机自由基

Science China Materials 2024年第3期67卷 709-728页

作者：张雅琦邱仁慧屈恺张成 j.fraser Stoddart 陈洪亮 Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310021China Zhejiang-Israel joint Laboratory of Self-Assembling Functional Materials ZJU-Hangzhou Global Scientific and Technological Innovation CentreZhejiang UniversityHangzhou 311215China Department of Chemistry and Innovation Center of Pesticide Research China Agricultural UniversityBeijing 100193China Department of Chemistry The University of Hong KongHong Kong SAR 999077China School of Chemistry University of New South WalesSydneyNSW 2052Australia Beijing National Laboratory for Molecular Sciences Beijing 100871China

空气稳定有机自由基的发现引起了人们对探究其在分子电子学和自旋电子学中应用的兴趣.这些自由基具有独特的开壳层电子结构,因而表现出特殊的电学特性.由于其较弱的旋轨耦合特性,也使得其成为自旋电子学的重要研究对象.此外,自由基还可... 详细信息

空气稳定有机自由基的发现引起了人们对探究其在分子电子学和自旋电子学中应用的兴趣.这些自由基具有独特的开壳层电子结构,因而表现出特殊的电学特性.由于其较弱的旋轨耦合特性,也使得其成为自旋电子学的重要研究对象.此外,自由基还可以通过二聚、分子识别和机械互锁等分子间相互作用来构筑超分子器件.本文综述了空气稳定有机自由基在电子学及自旋电子学中的应用,通过详述其卓越的电磁性能来拓展启发分子设计的多样性.本综述还概述了超分子自由基的制备方法和相关性质的研究进展,拓宽了单分子研究的范围.此外,自由基介导的单分子反应是一个新兴的研究方向,本文也对该领域的未来发展方向进行了展望.通过阐明空气稳定有机自由基的应用潜力,本文将有望对分子电子学和自旋电子学的研究产生一定的指导意义.

关键词： air-stable radicals molecular electronics spintronics supramolecular devices

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Mapping frontier molecular orbitals using photocurrents

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Science China Materials 2023年第9期66卷 3761-3762页

作者： Ping Zhou j.fraser Stoddart Hongliang Chen Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310027China ZjU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China Department of Chemistry Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA School of Chemistry University of New South WalesSydneyNSW 2052Australia

In the regime of coherent transport, the conductance of a molecular junction is governed(Fig. 1a) by the probability of electron transmission between the metal electrodes, a physica property which is affected significantly by the hybridization of frontier molecular orbitals(FMOs) with the continuous band of energy levels on the electrodes.

关键词： frontier molecular orbitals

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Mechanisms underlying feed intolerance in the critically ill: Implications for treatment

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World journal of Gastroenterology 2007年第29期13卷 3909-3917页

作者： Adam Deane Marianne j Chapman Robert j fraser Laura k Bryant Carly Burgstad Nam Q Nguyen Intensive Care Unit Royal Adelaide Hospital Adelaide South Australia Discipline of Medicine University of Adelaide and Investigation and Procedures Unit Repatriation General Hospital Adelaide South Australia Investigation and Procedures Unit Repatriation General Hospital Adelaide South Australia Department of Gastroenterology and Hepatology Royal Adelaide Hospital Adelaide South Australia

Malnutrition is associated with poor outcomes in critically ill patients. Although nutritional support is yet to be proven to improve mortality in non-malnourished critically ill patients, early enteral feeding is considered best practice. However, enteral feeding is often limited by delayed gastric emptying. The best method to clinically identify delayed gastric emptying and feed intolerance is unclear. Gastric residual volume （GRV） measured at the bedside is widely used as a surrogate marker for gastric emptying, but the value of GRV measurement has recently been disputed. While the mechanisms underlying delayed gastric emptying require further investigation, recent research has given a better appreciation of the pathophysiology. A number of pharmacological strategies are available to improve the success of feeding. Recent data suggest a combination of intravenous metoclopramide and en/thromycin to be the most successful treatment, but novel drug therapies should be explored. Simpler methods to access the duodenum and more distal small bowel for feed delivery are also under investigation. This review summarises current understanding of the factors responsible for, and mechanisms underlying feed intolerance in critical illness, together with the evidence for current practices. Areas requiring further research are also highlighted.

关键词： Critical illness Enteral nutrition Gastric emptying Gastric motility Gastrointestinal hormones Metoclopramide Erythromycin Prokinetic therapy

Impact of bolus volume on small intestinal intra-luminal impedance in healthy subjects

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World journal of Gastroenterology 2010年第17期16卷 2151-2157页

作者： Nam Q Nguyen Laura k Bryant Carly M Burgstad Robert j fraser Daniel Sifrim Richard H Holloway Department of Gastroenterology & Hepatology Royal Adelaide HospitalAdelaide 5000Australia Investigation and Procedures Unit Repatriation General HospitalDaw Park 5041Australia Department of Medicine Centre for Gastroen-terological ResearchK.U.LeuvenLeuven 3000Belgium

AIM: To assess the impact of bolus volume on the characteristics of small intestinal (SI) impedance ***: Concurrent SI manometry-impedance measurements were performed on 12 healthy volunteers to assess the pattern of proximal jejunal fluid bolus movement over a 14 *** subject was given 34 boluses of normal saline (volume from 1 to 30 mL) via the feeding tube placed immediately above the proximal margin of the studied segment.A bolus-induced impedance event occurred if there was > 12% impedance drop from baseline,over ≥ 3 consecutive segments within 10 s of bolus injection.A minor or major imped-ance event was defined as a duration of impedance drop jor impedance events (≥ 10 mL boluses = 63%,3 mL boluses = 17%,and < 3 mL boluses = 0%,P = 0.02).CONCLUSION: Bolus volume had an impact on the type and length of propagation of SI impedance events and a threshold of 2 mL is required to produce an event.

关键词： Bolus volume Health Impedance Luminal flow Small intestine

Making chiral molecular knots and links stereospecifically

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National Science Review 2023年第3期10卷 58-59页

作者： Huang Wu Chun Tang Long Zhang j.fraser Stoddart Department of Chemistry Northwestern University School of Chemistry University of New South Wales Stoddart Institute of Molecular Science Department of Chemistry Zhejiang University ZjU-Hangzhou Global Scientific and Technological Innovation Center

Topological structures [1,2],i.e.,knots and links,grace the macroscopic world in the form of biomorphs and artificial tools,all the way down to the molecular scale,such as catenated DNA and *** inherently exists in structures in which mirror-image topologies cannot be superimposed upon themselves without disassembling the topological *** the chirality we are most familiar with is based on stereogenic centers,

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Reticular exploration of uranium-based metal-organic frameworks with hexacarboxylate building units

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Nano Research 2021年第2期14卷 376-380页

作者： Zhijie Chen Penghao Li Xuan Zhang Mohammad Rasel Mian Xingjie Wang Peng Li Zhichang Liu Michael O’keeffe j.fraser Stoddart Omar k.Farha Department of Chemistry and International Institute for Nanotechnology Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA School of Molecular Sciences Arizona State UniversityTempeArizona 85287USA Institute for Molecular Design and Synthesis Tianjin University92 Weijin RoadTianjin 300072China School of Chemistry University of New South WalesSydneyNSW 2052Australia Department of Chemical&Biological Engineering Northwestern UniversityEvanstonIllinois 60208USA

The rational reticular design of metal-organic frameworks(MOFs)from building units of known geometries is essential for enriching the diversity of MOF *** and intriguing structures,however,can also arise from subtle changes in the rigidity/length of organic linkers and/or synthetic ***,we report three uranium-based MOF structures—i.e.,NU-135X(X=0,1,2)—synthesized from trigonal planar uranyl nodes and triptycene-based hexacarboxylate ligands with variable arm lengths.A new chiral 3,6-connected nuc net was observed in NU-1350,while the extended versions of the ligand led to 3-fold catenated MOFs(NU-1351 and NU-1352)with rare 3,6-connected cml-c3 *** differences in the topology of NU-1350 and NU-1351/NU-1352 could be attributed to the slight distortions of the shorter linker in the former from the ideal trigonal prism geometry to an octahedral geometry when coordinated to the trigonal planar uranyl nodes.

关键词： reticular chemistry uranium-based m etal-organic frameworks(MOFs) hexacarboxylate 3 6-connected net catenation actinide

三轴形变核^(131)Ba中的奇异集体激发模式

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物理学报 2024年第11期73卷 89-100页

作者：韦锐周厚兵王思成丁兵强赟华贾晨旭陈红星郭松 C.M.Petrache D.Mengoni A.Astier E.Dupont 吕冰锋 D.Bazzacco A.Boso A.Goasduff F.Recchia D.Testov F.Galtarossa G.jaworski D.R.Napoli S.Riccetto M.Siciliano j.j.Valiente-Dobon C.Andreoiu F.H.Garcia k.Ortner k.Whitmore A.Ataç-Nyberg T.Bäck B.Cederwall E.A.Lawrie I.kuti D.Sohler T.Marchlewski j.Srebrny A.Tucholski 广西师范大学物理科学与技术学院桂林541004 广西核物理与核技术重点实验室桂林541004 中国科学院近代物理研究所兰州730000 中国科学院大学北京100049 巴黎萨克雷大学 CNRS/IN2P3IJCLab奥赛91405 帕多瓦大学物理和天文学系帕多瓦I-35131 意大利国家核物理研究所帕多瓦分部帕多瓦I-35131 意大利国家核物理研究所莱尼亚罗国家实验室莱尼亚罗(帕多瓦)I-35020 费拉拉大学理学与自然科学院费拉拉西蒙菲莎大学化学系本拿比BC V5A 1S6 皇家理工学院物理系斯德哥摩尔S-10691 国家研究基金会iThemba加速器科学实验室西萨默塞特7123 西开普大学物理与天文系贝尔维尔ZA-7535 HUN-REN原子核研究所德布勒森4001 华沙巴斯德拉大学重离子实验室华沙02-093

利用意大利Legnaro实验室串列静电加速器提供的65 MeV^(13)C束流与122Sn靶的熔合蒸发反应布居了^(131)Ba的高自旋态,并搭建了新的能级纲图.新的能级纲图由15条转动带组成,包括三对手征双重带,其中两对正宇称手征带为赝自旋-手征四重带.... 详细信息

利用意大利Legnaro实验室串列静电加速器提供的65 MeV^(13)C束流与122Sn靶的熔合蒸发反应布居了^(131)Ba的高自旋态,并搭建了新的能级纲图.新的能级纲图由15条转动带组成,包括三对手征双重带,其中两对正宇称手征带为赝自旋-手征四重带.正负宇称手征带通过一系列增强的E1跃迁连接,表明它们之间存在八极关联.在低自旋区域搭建了一条新的转动带,通过一系列γ跃迁向νh1_(1/2)晕带退激.这种能级结构与摇摆带相似,但基于现有的实验证据还难以将它确认为摇摆带,不能排除其他集体激发机制,如γ振动的影响.

关键词：高自旋态手征带赝自旋八极关联摇摆运动

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Hydrogen-Bonded Organic Frameworks:A Rising Class of Porous Molecular Materials

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Accounts of Materials Research 2020年第1期1卷 77-87页

作者： Penghao Li Matthew R.Ryder j.fraser Stoddart Department of Chemistry Northwestern UniversityEvanstonIllinois 60208United States Neutron Scattering Division Oak Ridge National LaboratoryOak RidgeTennessee 37831United States Institute for Molecular Design and Synthesis Tianjin UniversityTianjin 300072China School of Chemistry University of New South WalesSydneyNSW 2052Australia

CONSPECTUS:Hydrogen-bonded organic frameworks(HOFs)are a class of porous molecular materials that rely on the assembly of organic building blocks by means of hydrogen-bonding interactions to form two-dimensional(2D)and three-dimensional(3D)crystalline *** reversible nature of the hydrogenbond formation endows HOFs with the attributes of solution processability and simple ***-quality single crystals of HOFs can be grown easily for unambiguous superstructure determination by single-crystal X-ray diffraction,which is crucial for the elucidation of superstructure−property *** the past decade,considerable progress has been achieved in realizing stable HOFs with permanent porosities by focusing on the design of molecular building blocks in order to introduce rigidity,auxiliary[π···π]interactions,and interpenetration of their frameworks to sustain the extended *** applications of HOFs are far-reaching,spanning catalysis,energy,and biomedical products as well as the storage and separation of fine *** this Account,we,first of all,provide an overview of the chronological development of HOFs,starting from the seminal work by Marsh and Duchamp in 1969 on the crystal superstructure of the hydrogen-bonded networks of trimesic *** identify the development of novel hydrogen-bonding motifs such as diaminotriazine(DTA),the introduction of the concept of molecular tectonics,and the establishment of permanent porosity in HOFs as being some of the milestones,which incentivized the current burgeoning research endeavors on developing HOFs as multifunctional *** Account is focused primarily on surveying the strategies for constructing porous 3D HOFs based on organic building blocks with peripheral carboxyl *** strategies are presented in the following categories:(1)the polycatenation of 2D networks by trigonal building blocks to form global 3D frameworks,(2)the utilization of building blocks with 3D geometrie

关键词： properties. bonding bonded

Eight decades of compositional change in a managed northern hardwood landscape

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Forest Ecosystems 2023年第3期10卷 398-410页

作者： Mark j.Ducey Olivia L.fraser Mariko Yamasaki Ethan P.Belair William B.Leak University of New Hampshire Department of Natural Resources and the Environment114 James HallDurhamNH03824USA U.S.D.A.Forest Service White Mountain National Forest71 White Mountain DriveCamptonNH03223USA U.S.D.A.Forest Service Northern Research Station271 Mast RoadDurhamNH03824USA The Nature Conservancy Natural Climate SolutionsAfrica Regional Portland Office45 Exchange StSuite 303PortlandME04101USA

We analyzed over 8 decades of change in forest composition(represented by species proportion of basal area)and size class from more than 400 permanent plots located on the Bartlett Experimental Forest in the White Mountains of New *** data represent one of the longest-term landscape-scale records of forest change based on permanent plots in North *** analyzed the plots based on elevation class,land type indicating assumed successional direction(grouped into coniferous and deciduous),and inventory period within managed and unmanaged portions of the *** ongoing shift from small-to large-diameter stems is clear across all species,in response to the overall aging of the forest following exploitative harvesting in the 19th *** compositional changes include a continuing decline in shade-intolerant species(paper birch and aspen),along with the mid-tolerant yellow *** increase in red maple abundance through the early 1990s has leveled off or *** shade-tolerant species,increases in beech and red spruce were largely consistent with assumed land type on unmanaged plots,but heavy marking against diseased beech on managed plots restricted increase of that *** maple declined in abundance except where silvicultural intervention helped maintain *** contrast,eastern hemlock showed a continuing expansion at all elevations below 600 *** data continue to show little or no evidence of upward migration of species,despite evidence of recent regional change in ***,the BEF is poised for substantial changes when emerald ash borer and hemlock woolly adelgid,both of which are known to infest nearby areas,do arrive.

关键词： Northern hardwoods Succession Stand dynamics Silviculture

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