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缺氧深海沉积物中菱铁矿的形成——细菌协合过程在古地磁学中的重要意义

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海洋地质译丛 1989年第6期 31-34页

作者： brooks b.ellwood 童春雷

最近对石灰岩磁性的研究根据两个理由证明,菱铁矿矿物在古地磁学中可能是极为重要的。第一,无论在取样之前、取样期间、或取样之后产生的菱铁矿的氧化产物,次生(子体)磁性矿物(磁铁矿、磁赤铁矿、赤铁矿)能够完全改变石灰岩样品的磁性;... 详细信息

最近对石灰岩磁性的研究根据两个理由证明,菱铁矿矿物在古地磁学中可能是极为重要的。第一,无论在取样之前、取样期间、或取样之后产生的菱铁矿的氧化产物,次生(子体)磁性矿物(磁铁矿、磁赤铁矿、赤铁矿)能够完全改变石灰岩样品的磁性;不了解这一点,将是造成研究灰岩,尤其是古生代灰岩的古地磁失败的一个主要原因。第二,弱磁性岩石中的菱铁矿指示了古地磁研究有取得成功的可能。因为,菱铁矿的存在可以指出原生磁载体仍旧是完好的,采用合适的退磁方法能够取得成功的结果。因此,我们断言,在缺氧深海沉积物的微环境下可以由铁的细菌异价还原产生的铁(Ⅱ)形成菱铁矿。

关键词：深海沉积菱铁矿细菌古地磁学

磁化率各向异性:在沉积学、火成岩石学以及构造地质学中的应用

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世界地质 1989年第1期8卷 94-99页

作者： William D.MacDonald brooks b.ellwood 张志强

一、引言如Graham（1954）所注意到的,磁化率各向异性（A MS）在研究地质过程中有很多用途。这种各向异性反映岩石磁化中磁化强度的方向性变化,主要是其中铁的氧化物特别是磁铁矿和赤铁矿。A MS常用一个椭球体表示,其三个主轴从大到小... 详细信息

一、引言如Graham（1954）所注意到的,磁化率各向异性（A MS）在研究地质过程中有很多用途。这种各向异性反映岩石磁化中磁化强度的方向性变化,主要是其中铁的氧化物特别是磁铁矿和赤铁矿。A MS常用一个椭球体表示,其三个主轴从大到小依次为kb>1b>、kb>2b>和kb>3b>。

关键词：磁化率构造地质学沉积学研究地质过程椭球体破火山口面理大地构造生物扰动冰川沉积

MIOCENE TERRESTRIAL VERTEbRATE SITES OF LOUISIANA, CENTRAL SOUTHERN COAST OF NORTH AMERICA

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MIOCENE TERRESTRIAL VERTEBRATE SITES OF LOUISIANA, CENTRAL S...

第二届国际古生物学大会

作者： Judith A.SCHIEbOUT Wulf A.GOSE John H.WRENN Michael J.WILLIAMS Mark D.HAGGE Julie L.HILL brooks b.ellwood Grant S.bOARDMAN Museum of Natural Science Louisiana State University baton Rouge LA 70803 USA.Department of Geology and Geophysics Louisiana State University Baton Rouge LA 70803 USA Department of Geological Sciences The University of Texas at Austin 1 University Station C1100 Austin Texas 78712-0254 48091 Bayou Fountain Apt. 403 Baton RougeLA 70820USA Museum of Natural Science Louisiana State University baton Rouge LA 70803 USA. Department of Geology and Geophysics Louisiana State University Baton Rouge LA 70803 USA Department of Geological Sciences The University of Texas at Austin 1 University Station C1100 Austin Texas 78712-0254 48091 Bayou Fountain Apt. 403 Baton Rouge LA 70820 USA

Terrestrial vertebrate sites in the Fleming Formation, first discovered in 1993 on Fort Polk in western Louisiana, had been the only source of Miocene terrestrial vertebrates in the state until discoveries in southeastern Louisiana in the Pascagoula Formation in June of 2005. 6,359 catalogued specimens, mainly mammals, have been recovered from western Louisiana, including the rhinoceros Aphelops, a gomphothere, two species of merychippine horse, the protoceratid Prosynthetoceras francisi, a large camel, a small peccary, Miomustela, a hedgehog, bats, shrews, two small beavers, rodents Copemys & Texomys, heteromyids, and squirrels, as well as lower vertebrates including turtles, snakes, frogs, toads, salamanders, and fish. Heavy veg-

关键词： North America Miocene Gulf Coast terrestrial mammals

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健康寿命概念变追捧初创公司争相入局

商业周刊（中文版） 2024年第12期 8-11页

作者： Mark ellwood 汪泽(译) 不详

疫情后,人们健康意识增强,关注这一领域商机的公司不断涌现。但“健康寿命”概念被一部分人质疑为敛财手段一切从寄来的一个深绿色的盒子开始,装着满满的测试装备。里面有盛放唾液和呼气样本的小瓶子,还有一个监测设备,在预约的面诊时... 详细信息

疫情后,人们健康意识增强,关注这一领域商机的公司不断涌现。但“健康寿命”概念被一部分人质疑为敛财手段一切从寄来的一个深绿色的盒子开始,装着满满的测试装备。里面有盛放唾液和呼气样本的小瓶子,还有一个监测设备,在预约的面诊时间之前需要佩戴几天。说明书指示我带上所有这些东西前往一处咨询室,它位于伦敦市中心一条树林掩映的街道上。这个地方靠近私立医院集中的哈利街,而这家公司的名称Viavi在一个亮闪闪的黄铜蜂鸣器上面,很不显眼。根据具体的项目不同,面诊可能需要两个工作日。

关键词：私立医院初创公司健康寿命伦敦市中心监测设备深绿色蜂鸣器咨询室

black hole shadows in Einstein-bel-Robinson gravity

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Chinese Physics C 2024年第5期48卷 272-283页

作者： b.Hamil b.C.Lütfüoğlu Laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-bel-Robinson (EbR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EbR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-bel-Robinson gravity plasma

Water Vapor Information from Satellite and Its Applications

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Advances in Atmospheric Sciences 2024年第1期41卷 188-189页

作者： b.J.SOHN School of Earth and Environmental Sciences Seoul National UniversitySeoul 08826Korea

Water vapor is a critical component of the hydrological cycle because it plays a vital role in transporting water from one part of the cycle to *** vapor evaporated from surfaces such as oceans,lakes,and rivers conden... 详细信息

关键词： motion oceans lakes

Soils in extraterrestrial space: Need for studies under microgravity

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Pedosphere 2024年第1期34卷 13-14页

作者： M.b.KIRKHAM Department of Agronomy Kansas State UniversityManhattan KS 66506USA

With the increased interest of plants in space, gravity cannot be ignored when studying soil-plant-water relations. Therefore, it is important to understand the water relations of soils under zero gravity in space or under reduced gravity on the Moon or Mars. This paper outlines the problems of moving water in soils under zero gravity or microgravity, as well as growing plants in these soils. It is suggested that microgravity experiments could be done on Earth using both soils and plants. Results from such experiments could be used to grow plants when mankind establishes bases on the Moon and Mars.

关键词： soils soil bases

CompactChain:an efficient stateless chain for UTXO-model blockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： b Swaroopa REDDY T Uday Kiran REDDY Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UTXO(Unspent Transaction Output)based blockchain systems into two RSA *** first accumulator is called Transaction Output(TXO)commitment which represents the TXO *** second one is called Spent Transaction Output(STXO)commitment which represents the STXO *** this work,we discuss three algorithms:(i)To update the TXO and STXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)To prove the transaction’s validity by providing a membership witness in TXO commitment and non-membership witness against STXO commitment for a coin being spent by a user;(iii)To update the witness for the coin that is not yet spent;The experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(Transactions per second(TPS)).

关键词： stateless blockchain RSA Accumulator STXO commitment TXO commitment UTXO Non-interactive Proof of Exponentiation(NI-PoE) Transactions per second(TPS)

Closing the Experiment-Modeling-Perturbation Loop in Whole-brain Neuroscience

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Neuroscience bulletin 2024年第8期40卷 1212-1214页

作者： Misha b.Ahrens Janelia Research Campus Howard Hughes Medical InstituteAshburnVAUSA

Understanding the mechanisms by which the central nervous system processes information,forms memories,makes decisions,and executes actions is a challenging *** is an interdisciplinary field in which cell biology,anatomy,network theory,and other scientific disciplines come together to jointly push our knowledge of brain function forward.

关键词： execute knowledge jointly