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Water transport to the core–mantle boundary

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National Science Review 2021年第4期8卷 13-16页

作者： Michael j.Walter Earth and Planets Laboratory Carnegie Institution for Science

Water can have remarkable effects when exposed to rocks at high pressures and temperatures. It can form new minerals with unique properties and often profoundly affects the physical, transport and rheological properti...

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Gas exchange and water relations of young potted loquat *** under progressive drought conditions

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journal of Integrative Agriculture 2018年第6期17卷 1360-1368页

作者： A.Stellfeldt M.A.Maldonado j.j.Hueso j.Cuevas Department of Agronomy University of AlmeriaceiA3 Almeria 04120Spain Experimental Station of Cajamar Las Palmerillas ceiA3 Almeria 04710Spain

Relationships between plant water status and gas exchange parameters at increasing levels of water stress were determined in Algerie loquats which grown in 50 I pots. Changes in soil water content and stem water potential and their effects on stomatal conductance （Gs ） and net photosynthesis （Pn） rate were followed in control plants and in plants without irrigation until the latter reached near permanent wilting point and some leaf abscission took place. Then, the irrigation was restarted and the comparison repeated. Soil water content and stem water potential gradually diminished in response to drought reaching the minimum values of 0.9 mm and -5.0 MPa, respectively, 9 days after watering suspension. Compromised plant water status had drastic effects on Gs values that dropped by 97％ in the last day of the drought period. Pn was diminished by 80％ at the end of the drought period. The increasing levels of water stress did not cause a steady increase in leaf temperature in non-irrigated plants. Non-irrigated plants wilted and lost some leaves due to the severity of the water stress. However, all non-irrigated plants survived and reached similar Pn than control plants just a week after the irrigation was restarted, confirming drought tolerance of loquat and suggesting that photosynthesis machinery remained intact.

关键词： Eriobotrya japonica deficit irrigation stem water potential net photosynthetic rate stomatal conductance

Ferrofluid moving thin films for active flow control

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Chinese journal of Aeronautics 2021年第5期34卷 115-119页

作者： Francisco j.ARIAS Department of Fluid Mechanics Polytechnic University of CataloniaESEIAATC/Colom 1108222 BarcelonaSpain

Ferrofluid moving thin films and their possible significance with regard to active flow control for lift and attack angle enhancement are *** this strategy,a very thin film of ferrofluid is strongly attached at the wall of the wing by a normal magnetic field from below and pumped tangentially along the *** a simplified physical model and from the available experimental data on moving walls,the expected lift enhancement and effect on the attack angle were *** research and design is required in order to explore the possibilities in the use of ferrofluid moving thin films.

关键词： Active flow control Boundary layer separation Ferrofluid

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： David j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Review of current method to determine outburst threshold limits in Australian underground coal mines

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International journal of Mining Science and Technology 2019年第6期29卷 859-865页

作者： Dennis j.Black CoalGAS Department of Civil Mining and Environmental Engineering University of Wollongong

Desorption rate index(DRI)was presented to the Australian underground coal industry in 1995 as a means for determining outburst threshold limits for Australian coal *** is a measure of the gas volume released from a coal sample in the first 30 s of crushing during the Q3 stage of gas content testing,multiplied by the ratio between measured Q3 and *** were identified between QM and DRI for both CO2 and CH4 rich coal samples collected from the Bulli Seam at West Cliff Colliery and that identified relationship was referred to as the Bulli Seam *** outburst mining gas content threshold limit values specified for the Bulli Seam at that time,when applied to the QM-DRI Bulli Seam benchmark,was shown to closely align with a DRI value of 900(DRI900),for both CO2 and CH4 rich seam gas *** Australian coal industry adopted the DRI900 as the basis for determining outburst gas content TLV for Australian coal *** mining experience in Australia has shown that gas content is not the only significant factor that impacts outburst risk,as all significant outburst events have been associated with abnormal geological conditions,such as faults and ***,assessing the potential application of additional outburst risk factors,to accurately define outburst risk zones,set safe mining threshold levels,and determine appropriate mining controls,warrants further *** Australian coal mines have implemented mining procedures enabling mining to continue in areas with gas content greater than the TLV determined using the DRI900 approach,without inducing an *** is a broad lack of understanding among Australian coal mine operators as to the procedure and calculations used to determine ***,there has been growing concern regarding the accuracy and validity of the DRI900 method for determining outburst TLV.A comprehensive set of gas data has been collected from Australian coal seams,including the Bulli Seam,and t

关键词： Outburst Desorption rate DRI Threshold limit

Global weirding at mass extinction horizons

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National Science Review 2024年第1期11卷 10-12页

作者： Gregory j.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Why Marginal Pricing?

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journal of Modern Power Systems and Clean Energy 2023年第3期11卷 693-697页

作者： Antonio j.Conejo Department of Integrated Systems Engineering and the Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOhio 43210USA

Under perfect competition,marginal pricing results in short-term efficiency and the subsequent right short-term price ***,the main reason for the adoption of marginal pricing is not the above,but investment cost *** is,the fact that the profits obtained by infra-marginal technologies(technologies whose production cost is below the marginal price)allow them just to recover their investment *** the other hand,if the perfect competition assumption is removed,investment over-recovery or under-recovery generally occurs for infra-marginal technologies.

关键词： Electricity market marginal pricing investment cost recovery maximum social welfare right spatial and temporal price signals

Characterization of mudrocks:a practical application of advanced laboratory testing

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第1期12卷 1-14页

作者： Richard j.jARDINE Department of Civil and Environmental Engineering Imperial College London

An integrated approach to geomaterial characterization is advocated that combines geology, in-situ testing, fabric studies, routine index experiments and advanced laboratory testing. It is shown that advanced laboratory testing can explore features such as kinematic yielding and anisotropy in stiffness or shear strength that would otherwise be impossible to quantify. A detailed study performed in London clay at the new Heathrow Terminal 5 site is used to illustrate the arguments made. It is shown that the London clay has strong anisotropy in stiffness, is highly non-linear over the strain range of engineering interest, has markedly anisotropic shear strength characteristics and exhibits a pronounced degree of brittleness. These features can impact significantly on the practical design and analysis of civil engineering works including shallow and deep foundations, tunnels and excavations, and the stability of slopes.

关键词： Mudrock Fabric Anisotropy Hollow cylinder tests

Two distinct Paleozoic metamorphic events in the Tarim-North China Collage

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National Science Review 2023年第2期10卷 7-8页

作者： jérémie Soldner State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences CAS Center for Excellence in Deep Earth Science

The Central Asian Or ogenic Belt(CAOB) [1],which includes the Altaids in Central and Northern Asia [2],is the largest accretionary orogen formed during the subduction of the Paleo-Asian Ocean and the Panthalassa Ocean in the period of the Late Proterozoic to Late Paleozoic [3].Closure of the Paleo-Asian Ocean is attributed to the northward drift of the North China and Tarim cratons leading to the massive shortening and oroclinal buckling of the CAOB accretionary system in the Permian [4].

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