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太古宙和元古宙时期的地壳演化──从地壳地震学获得的证据

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地质地球化学 1994年第1期22卷 26-28页

作者： R.J.durrheim w.d.mooney 吴伟成陈伟沈阳黄金学院

通过分析整个世界太古宇和元古宇地区的地震波速模型，发现太古宇地区地壳的厚度为35km左右（碰撞带边缘除外），而元古宇地壳的厚度则显然要大得多，大致为45km，并且在其基底有一较厚的高速层（＞7km/s）。我们认为有两种模式可以解... 详细信息

通过分析整个世界太古宇和元古宇地区的地震波速模型，发现太古宇地区地壳的厚度为35km左右（碰撞带边缘除外），而元古宇地壳的厚度则显然要大得多，大致为45km，并且在其基底有一较厚的高速层（＞7km/s）。我们认为有两种模式可以解释这些差异。第一种模式把这种差异归因于上地幔成分的改变。太古宇地幔中的温度较高，因而导致了科马提熔岩的喷发，结果使得岩石圈过分贫化而不能产生大量的玄武质熔体。元古宇地壳是在富地幔之上发育而成，经后的部分熔融作用造成质武玄岩浆的底侵和地壳膨胀。第二种模式认为，在太古宇高温地幔中的对流作用由于过分的紊乱而不能支撑稳定的长寿命俯冲带。到了元古宙时期，由于地幔已足够冷却，因而形成了大量的岛弧和陆弧，同时由于玄武岩浆的底侵作用而形成了上述的高速玄武岩基底层。

关键词：地壳演化地震学太古宙元古宙

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川滇地区地壳上地幔三维速度结构研究

地震学报 2002年第1期24卷 1-16页

作者：王椿镛 w.d.mooney 王溪莉吴建平楼海王飞中国地震局地球物理研究所中国北京100081 美国地质调查局美国门罗帕克ca94025

根据云南和四川地震台网 1 74个台站记录的 4 62 5个区域地震初至 P波和 S波走时资料 ,并结合其它深部地球物理资料 ,确定了川滇地区地壳上地幔三维速度结构 .在上地壳速度异常分布中 ,四川盆地为正异常 ,川西高原为负异常 ,龙门山断裂... 详细信息

根据云南和四川地震台网 1 74个台站记录的 4 62 5个区域地震初至 P波和 S波走时资料 ,并结合其它深部地球物理资料 ,确定了川滇地区地壳上地幔三维速度结构 .在上地壳速度异常分布中 ,四川盆地为正异常 ,川西高原为负异常 ,龙门山断裂带为正、负异常的边界 .龙门山断裂、鲜水河断裂以及红河断裂等 ,在下地壳和上地幔的速度异常中仍显示出构造分界特征 ,说明它们可能穿透了莫霍界面 .腾冲火山区和攀西构造带在 50 km深度上呈现负速度异常 ,与上地幔温度和物质组成的差异相联系 .川滇地区地壳结构的总体特征是 :地壳和上地幔的低平均速度 ,地壳厚度变化剧烈 ,地壳和 (或 )上地幔存在高导层、高热流值 .这些同印度板块与欧亚板块碰撞的构造背景有关 .川滇菱形块体在地壳内总体上为正常或正异常速度 ,而其边界的深大走滑断裂存在负速度异常 ,它有助于地壳块体沿断裂的侧向挤出 .在主要的地震带上 ,中下地壳的负速度异常与地震活动性相关 .多数强烈地震发生在具有正速度异常或正常速度分布的上中地壳深度上。

关键词：区域地震莫霍界面三维速度结构网格方法板块碰撞地震活动性川滇地区

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大陆地壳(一)

世界地震译丛 2004年第1期35卷 75-83页

作者： w.d.mooney 郑文俊天津市地震局

1.地壳研究的方法 2.大陆地壳的深部构造 3.全球地壳厚度 4.大陆断层带 5.地壳中的流体 6.大陆地壳的成分 7.大陆地壳的起源地质区:以相似的地质历史和演变过程为特征的大地壳区,例如造山带、台地、大陆弧、裂谷及扩展的地壳。

关键词：地壳厚度造山带大陆弧裂谷褶皱带构造带地震波速度地震波速世界地震译丛岩石层厚度地球化学地球科学莫霍面地壳结构地盾地台地震速度

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大陆地壳(二)

世界地震译丛 2004年第2期35卷 79-84页

作者： w.d.mooney 郑文俊楼海吕春来不详天津市地震局

全球地壳厚度等值线图(图6)显示了地壳厚度的双峰标度。海洋盆地的地壳厚度为6～7km(不包括4～5km的水层)，而大陆部分的平均厚度为39．7km。在海洋一大陆边缘的典型地壳厚度是30km，并向大陆内部逐渐增厚到40～45km。厚度超过50km的地... 详细信息

全球地壳厚度等值线图(图6)显示了地壳厚度的双峰标度。海洋盆地的地壳厚度为6～7km(不包括4～5km的水层)，而大陆部分的平均厚度为39．7km。在海洋一大陆边缘的典型地壳厚度是30km，并向大陆内部逐渐增厚到40～45km。厚度超过50km的地壳局限在几个地区。

关键词：大陆地壳地壳厚度海洋盆地大陆断层带

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.d.Küntz d.Koutroumpa w.R.dunn A.Foster F.S.Porter d.G.Sibeck B.walsh The Henry A.Rowland department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

while we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).with a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

BMPRⅡ^(+)neural precursor cells isolated and characterized from organotypic neurospheres:an in vitro model of human fetal spinal cord development

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Neural Regeneration Research 2024年第2期19卷 447-457页

作者： Michael w.weible II Michael d.Lovelace Hamish d.Mundell Tsz wai Rosita Pang Tailoi Chan-Ling Bosch Institute Discipline of Anatomy and Histology(F13)University of SydneySydneyNSWAustralia School of Environment and Science Griffith UniversityNathanQLDAustralia discipline of Medicine Nepean Clinical SchoolFaculty of Medicine and HealthUniversity of SydneyKingswoodNSWAustralia New South wales Brain Tissue Resource Centre School of Medical SciencesFaculty of Medicine and HealthUniversity of SydneyCharles Perkins Centre(D17)SydneyNSWAustralia

Roof plate secretion of bone morphogenetic proteins(BMPs)directs the cellular fate of sensory neurons during spinal cord development,including the formation of the ascending sensory columns,though their biology is not well ***-ⅡBMP receptor(BMPRⅡ),the cognate receptor,is expressed by neural precursor cells during embryogenesis;however,an in vitro method of enriching BMPRⅡ^(+)human neural precursor cells(hNPCs)from the fetal spinal cord is *** was undertaken on intact second-trimester human fetal spinal cord using antibodies to BMPRⅡand leukemia inhibitory factor(LIF).Regions of highest BMPRⅡ^(+)immunofluorescence localized to sensory *** and meningeal-associated BMPRⅡ^(+)vascular cells were identified in both intact fetal spinal cord and cortex by co-positivity with vascular lineage markers,Cd34/*** immunostaining identified a population of somas concentrated in dorsal and ventral horn interneurons,mirroring the expression of LIF receptor/Cd118.A combination of LIF supplementation and high-density culture maintained culture growth beyond 10 passages,while synergistically increasing the proportion of neurospheres with a stratified,*** neurospheres were characterized by BMPRⅡ^(+)/MAP2ab^(+/–)/βⅢ-tubulin^(+)/nestin^(–)/vimentin^(–)/GFAP^(–)/NeuN^(–)surface hNPCs surrounding a heterogeneous core ofβⅢ-tubulin^(+)/nestin^(+)/vimentin^(+)/GFAP^(+)/MAP2ab^(–)/NeuN^(–)multipotent *** cultures from tripotential neurospheres contained neuronal(βⅢ-tubulin^(+)),astrocytic(GFAP+),and oligodendrocytic(O4+)lineage ***-activated cell sorting-sorted BMPRⅡ^(+)hNPCs were MAP2ab^(+/–)/βⅢ-tubulin^(+)/GFAP^(–)/O4^(–)in *** is the first isolation of BMPRⅡ^(+)hNPCs identified and characterized in human fetal spinal *** data show that LIF combines synergistically with high-density reaggregate cultures to support the organotypic reorganization of neurospheres,characterize

关键词： BMPRⅡ bone morphogenetic protein histotypic human spinal cord development leukemia inhibitory factor neurosphere organotypic reaggregate sensory columns

SMILE soft X-ray Imager flight model CCd370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons d.J.Hall O.Hetherington T.w.Buggey T.Arnold M.w.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

Throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCd370s within the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCds have been characterised,the two flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show that there is a cluster of bright pixels in the flight spa re which increases in size with tempe *** at the nominal ope rating tempe rature(-120℃) it is within the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades with temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCd soft X-ray imager characterisation SMILE

determining minimum sample size for the conditioned Latin hypercube sampling algorithm

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Pedosphere 2024年第3期34卷 530-539页

作者： daniel d.SAURETTE Asim BISwAS Richard J.HECK Adam w.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(dSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental *** to adequately sample the predictors have been well documented,with the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the dSM *** advances in sampling design,a critical gap remains in determining the number of samples required for dSM *** propose a simple workflow and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-diaconis rule for determining optimal bin *** preprocessing was included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the *** on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and lower bounds of the QR were used as a scaling factor to determine minimum sample *** technique was applied to a field-scale set of environmental covariates for a well-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of *** results showed increasing minimum sample size with an increase in the QR *** sample size increased from 44 to 83 when the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%*** technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin width digital soil mapping normal distribution quantile range sampling design

Twisted fiber microfluidics:a cutting-edge approach to 3d spiral devices

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Microsystems & Nanoengineering 2024年第1期10卷 193-202页

作者： Shunsuke Kato daniel w.Carlson Amy Q.Shen Yuanyuan Guo department of Electrical Information and Physics EngineeringSchool of EngineeringTohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan Micro/Bio/Nanofluidics Unit Okinawa Institute of Science and TechnologyOnnaKunigami-gun 904-0495 OkinawaJapan Frontier Research Institute for Interdisciplinary Sciences(FRIS) Tohoku UniversityAoba-kuSendai 980-0845 MiyagiJapan Graduate School of Biomedical Engineering Tohoku UniversityAoba-kuSendai 980-8579 MiyagiJapan department of Physiology Graduate School of MedicineTohoku UniversityAoba-kuSendai 980-8575 MiyagiJapan

The development of 3d spiral microfluidics has opened new avenues for leveraging inertial focusing to analyze small fluid volumes,thereby advancing research across chemical,physical,and biological *** traditional straight microchannels rely solely on inertial lift forces,the novel spiral geometry generates dean drag forces,eliminating the necessity for external fields in fluid ***,fabricating 3d spiral microfluidics remains a labor-intensive and costly endeavor,hindering its widespread ***,conventional lithographic methods primarily yield 2d planar devices,thereby limiting the selection of materials and geometrical *** address these challenges,this work introduces a streamlined fabrication method for 3d spiral microfluidic devices,employing rotational force within a miniaturized thermal drawing process,termed as *** innovation allows for rapid prototyping of twisted fiber-based microfluidics featuring versatility in material selection and heightened geometric *** validate the performance of these devices,we combined computational modeling with microtomographic particle image velocimetry(uTPiM)to comprehensively characterize the 3d flow *** results corroborate the presence of a steady secondary flow,underscoring the effectiveness of our *** 3d spiral microfluidics platform paves the way for exploring intricate microflow dynamics,with promising applications in areas such as drug delivery,diagnostics,and lab-on-a-chip systems.

关键词： thereby straight twisted