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Masses for free-floating planets and dwarf planets

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Research in Astronomy and Astrophysics 2021年第6期21卷 207-221页

作者： Andrew gould 臧伟呈毛淑德东苏勃 Max-Planck-Institute for Astronomy Konigstuhl 17D-69117 HeidelbergGermany department of Astronomy Ohio State University140 W.18th Ave.ColumbusOH 43210USA department of Astronomy Tsinghua UniversityBeijing 100084China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China

The mass and distance functions of free-floating planets(FFPs) would give major insights into the formation and evolution of planetary systems, including any systematic differences between those in the disk and bulge. We show that the only way to measure the mass and distance of individual FFPs over a broad range of distances is to observe them simultaneously from two observatories separated by d ~ O(0.01 au)(to measure their microlens parallax πE) and to focus on the finite-source point-lens(FSPL) events(which yield the Einstein radius θE). By combining the existing KMTNet 3-telescope observatory with a 0.3 m 4 deg2 telescope at L2, of order 130 such measurements could be made over four years, down to about M ~ 6 M⊕for bulge FFPs and M ~ 0.7 M⊕for disk FFPs. The same experiment would return masses and distances for many bound planetary systems. A more ambitious experiment, with two 0.5 m satellites(one at L2 and the other nearer Earth) and similar camera layout but in the infrared, could measure masses and distances of sub-Moon mass objects, and thereby probe(and distinguish between) genuine sub-Moon FFPs and sub-Moon "dwarf planets" in exo-Kuiper Belts and exo-Oort Clouds.

关键词： gravitational lensing:micro

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Soil Nutrients, Landscape Age, and <i>Sphagno-Eriophoretum vaginati</i>Plant Communities in Arctic Moist-Acidic Tundra Landscapes

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Open Journal of Soil Science 2014年第11期4卷 375-387页

作者： Joel A. Mercado-díaz William A. gould Grizelle González USdA Forest Service International Institute of Tropical Forestry Jardín Botánico Sur 1201 Calle Ceiba Río Piedras Puerto Rico

Most research exploring the relationship between soil chemistry and vegetation in Alaskan Arctic tundra landscapes has focused on describing differences in soil elemental concentrations (e.g. C, N and P) of areas with contrasting vegetation types or landscape age. In this work we assess the effect of landscape age on physico-chemical parameters in organic and mineral soils from two long-term research sites in northern Alaska, the Toolik Lake and Imnavait grids. These two sites have contrasting landscape age but similar vegetation composition. We also used correlation analysis to evaluate if differences in any of these parameters were linked with between-site variation in the abundance of growth forms. Our analysis was narrowed to soils in Sphagno-Eriophoretum vaginati plant communities. We found no significant differences between these sites for most parameters evaluated, except for total Ca which was significantly higher in organic soils from Imnavait vs. Toolik and total Na which was significantly higher in mineral horizons from Toolik compared to Imnavait. Moreover, the abundance of non-Sphagnum mosses was positively correlated with total Ca in organic soils, whereas the abundance of forbs, non-Sphagnum mosses and bryophytes was negatively correlated with total Na in mineral soils. We suggest that differences in the concentration of these two elements are most likely tied to landscape age differences between these sites. However, since observed dissimilarity in terms of total Ca in organic soils and total Na in mineral soils is concordant with correlation patterns observed between these elements and the aforementioned growth forms, it is likely that existing differences in vegetation composition between these sites are also influencing the concentration of these elements in soils, particularly that of Ca, since non-Sphagnum mosses are dominant above organic soils and are therefore expected to significantly influence biogeochemical processes at this horizon. Thus,

关键词： Arctic Alaska Soil Nutrients Moist-Acidic Tussock Tundra Vegetation

Embolization of ruptured iliac artery aneurysms

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介入放射学杂志 1995年第3期 183-184页

作者： d.A.gould R.d.Edwards S.P.Sinha department of Radiology,Broadgreen Hospital and Royal Liverpool University Hospital,Liverpool UK

Spontaneous rupture of iliac artery aneurysms is uncommon but is associatedwith a high surgical *** report two cases which were treated successfully by tran- scatheter embolization and review the literature.

关键词： high

Screening Effects on van der Waals Interactions

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Screening Effects on van der Waals Interactions

第十三届全国量子化学会议

作者： Li M. Reimers JR gould T dobson J Shanghai University University of Technology Sydney Griffith University

Van der Waals interactions are ubiquitous in the world, and have been recognized as critical to most important properties of natural matters including proteins and dNA(deoxyribonucleic acid). In chemical and biochemical envi ronments,mode rn empirical app ro aches like Grimme ’s d3 method allow for fast evaluation of these forces in electronic-structure calculations. However, this and related methods are based on London’s approximation to the van der Waa ls force as arising from pairwise-additive atomic fluctuations and polarizations. Recently,the dobson classification was introduced to understand the shortcomings of such approaches, shortcomings particularly relevant for low-dimensional molecules and conductors such as graphene, C, large aromatic molecules, and nanotubes. An important experimental characterisation of non-additive effects was the recent demonstration the placing a graphene layer between a silica substrate and silica AFM tip switches off the van der Waals inter action between tip and substrate through a Faraday-cage screening effect. We develop computational models to understand this effect, comparing the pairwise-additive d3 method to the popular many-bond dispersion(MBd) method for treating screening, and a new method developed by gould to include and improve not only these contributions but also those from long-range fluctuations(related to the Casimir effect).

关键词： Van der Waals interaction Non-additive effect Long-range Fluctuation

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关于固体推进剂燃烧不稳定性研究

推进技术 1984年第2期 56-63页

作者： gould P.d. ,Penny.P.d. ,WellingsP.C ,马玉风

本文介绍了英国火箭推进研究院进行固体推进剂燃烧不稳定性研究的工作计划。文中讨论了数据采集和处理的技术,并例举了实用发动机燃烧的不稳定性。还描述了研究不稳定性的发动机和测量在振荡压力和速度条件下固体推进剂试样的燃烧速率... 详细信息

本文介绍了英国火箭推进研究院进行固体推进剂燃烧不稳定性研究的工作计划。文中讨论了数据采集和处理的技术,并例举了实用发动机燃烧的不稳定性。还描述了研究不稳定性的发动机和测量在振荡压力和速度条件下固体推进剂试样的燃烧速率系统。给出一些实测结果的例子。

关键词：固体推进剂发动机燃烧不稳定推进剂燃速推进剂燃烧速度不稳定性

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管理的数量概念

管理的数量概念

作者： G.d.·埃本(G.d. Eppen) F.J.·高尔德(F.J. gould)

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管理的数量概念

管理的数量概念

丛书名：现代管理译丛

1986年

作者：（美）埃本（Eppen G.d.）（美）高尔德（gould F.J.）赵国士译

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人体抗血友病因子Ⅸ的分子克隆

遗传工程 1983年第2期 22-24页

作者： K.H.Choo K.G.gould d.J.G.Rees G.Brownlee 陈珞京

因子Ⅸ的功能性缺陷能导致一种称为Chrstimas病或血友病B的出血失常症,这种因子Ⅸ是血液凝决中的凝集因子之一。血友病B和A(因子Ⅷ(C)缺陷)都是Ⅹ染色体连锁的,在男性中大约以一万分之一的频率而出现。血友病B中,因子Ⅸ的功能性改变的... 详细信息

因子Ⅸ的功能性缺陷能导致一种称为Chrstimas病或血友病B的出血失常症,这种因子Ⅸ是血液凝决中的凝集因子之一。血友病B和A(因子Ⅷ(C)缺陷)都是Ⅹ染色体连锁的,在男性中大约以一万分之一的频率而出现。血友病B中,因子Ⅸ的功能性改变的分子基础尚不太清楚。为了阐明这种病的分子基础,我们首先进行了因子Ⅸ基因的分子

关键词：分子克隆核昔酸序列分析 cdNA 血友病凝血障碍

髋关节保护器降低长期接受护理人群跌倒所致髋部骨折风险的效果(摘译)

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伤害医学（电子版） 2020年第2期9卷 60-63页

作者：陈晓东(译) 杨怿健(审校) 李丽萍(审校) Alexandra MB Korall Fabio Feldman Yijian Yang Ian d Cameron Pet-Ming Leung Joanie Sims-gould Stephen N Robinovitch 汕头大学医学院伤害预防研究中心汕头515041 香港中文大学体育运动科学系中国香港999077

跌倒是导致老年人髋部骨折的主要原因,而髋部骨折会增加死亡率及医疗负担。长期接受护理(long-term care,LTC)的老年人发生跌倒及髋部骨折是社区老年人的两倍,因此预防跌倒对接受长期接受护理的老年人来说是一个重大挑战。髋关节保护器... 详细信息

跌倒是导致老年人髋部骨折的主要原因,而髋部骨折会增加死亡率及医疗负担。长期接受护理(long-term care,LTC)的老年人发生跌倒及髋部骨折是社区老年人的两倍,因此预防跌倒对接受长期接受护理的老年人来说是一个重大挑战。髋关节保护器由固定在髋部股骨大转子附近的带软垫或硬穹顶的特殊服饰组成.

关键词：髋部骨折股骨大转子医疗负担预防跌倒社区老年人髋关节保护器护理人群

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