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Theory and classification of mass extinction causation

National science Review 2024年第1期11卷 16-36页

作者： Thomas j.Algeo jun shen state Key Laboratory of Biogeology and Environmental Geology China University of Geosciences—Wuhan state Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences—Wuhan Department of Geosciences University of Cincinnati

Theory regarding the causation of mass extinctions is in need of systematization, which is the focus of this contribution. Every mass extinction has both an ultimate cause, i.e. the trigger that leads to various climato-environmental changes, and one or more proximate cause(s), i.e. the specific climato-environmental changes that result in elevated biotic mortality. With regard to ultimate causes, strong cases can be made that bolide(i.e. meteor) impacts, large igneous province(LIP) eruptions and bioevolutionary events have each triggered one or more of the Phanerozoic Big Five mass extinctions, and that tectono-oceanic changes have triggered some second-order extinction events. Apart from bolide impacts, other astronomical triggers(*** flares, gamma bursts and supernova explosions) remain entirely in the realm of speculation. With regard to proximate mechanisms, most extinctions are related to either carbon-release or carbon-burial processes, the former being associated with climatic warming, ocean acidification, reduced marine productivity and lower carbonate δ13C values, and the latter with climatic cooling, increased marine productivity and higher carbonate δ13C values. Environmental parameters such as marine redox conditions and terrestrial weathering intensity do not show consistent relationships with carbon-cycle *** this context, mass extinction causation can be usefully classified using a matrix of ultimate and proximate factors. Among the Big Five mass extinctions, the end-Cretaceous biocrisis is an example of a bolide-triggered carbon-release event, the end-Permian and end-Triassic biocrises are examples of LIP-triggered carbon-release events, and the Late Ordovician and Late Devonian biocrises are examples of bioevolution-triggered carbon-burial events. Whereas the bolide-impact and LIP-eruption mechanisms appear to invariably cause carbon release, bioevolutionary triggers can result in variable carbon-cycle changes, e.g. carbon burial durin

关键词： biocrisis ultimate cause proximate cause bolide large igneous province bioevolutionary event

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Enabling Technologies for Autonomous Robotic systems in Manufacturing

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Transactions of Nanjing University of Aeronautics and Astronautics 2024年第4期41卷 403-431页

作者： ERDŐs Gábor ABAI Kristóf BEREGI Richárd CsEMPEsZ jános CsERTEG Tamás GODÓGábor HAj.s.Mátyás HÁY Borbála HORVÁTH Dániel HORVÁTH Gergely jUNIKIÁdám KEMÉNY Zsolt KOVÁCs András NACsA jános PANITI Imre PEDONE Gianfranco TAKÁCs Emma TIPARY Bence ZAHORÁN László VÁNCZA józsef Institute for Computer science and Control Hungarian Research Network(HUN-REN SZTAKI)BudapestHungary Department of Manufacturing science and Technology Budapest University of Technology and Economics(BME)BudapestHungary EPIC InnoLabs Nonprofit Ltd. BudapestHungary Eötvös Loránd University(ELTE) BudapestHungary

Research of autonomous manufacturing systems is motivated both by the new technical possibilities of cyber-physical systems and by the practical needs of the *** operation in semi-structured industrial environments can now be supported by advanced sensor technologies,digital twins,artificial intelligence and novel communication *** enable real-time monitoring of production processes,situation recognition and prediction,automated and adaptive(re)planning,teamwork and performance improvement by *** paper summarizes the main requirements towards autonomous industrial robotics and suggests a generic workflow for realizing such *** case studies will be presented from recent practice at HUN-REN sZTAKI in a broad range of domains such as assembly,welding,grinding,picking and placing,and *** various solutions have in common that they use a generic digital twin concept as their *** making general recommendations for realizing autonomous robotic solutions in the industry,open issues for future research will be discussed.

关键词： industrial robotics autonomy digital twin enabling technology

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Generalized Baumslag-solitar Graphs with soluble Fundamental Groups

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Algebra Colloquium 2014年第1期21卷 53-58页

作者： Alberto L. Delgado Derek j.s. Robinson Mathew Timm vDepartment of Mathematics illinois State University Normal IL 61790 USA Department of Mathematics University of Illinois at Urbana-Champaign Urbana IL 61801 USA Department of Mathematics Bradley University Peoria IL 61625 USA

It is shown that the generalized Baumslag-solitar graphs which have soluble fundamental groups can be constructed from four simple types of graph by a process of decoration. The method of proof is elementary and emplo... 详细信息

关键词： generalized Baumslag-solitar graph soluble fundamental group

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Optimizing oncolytic virus design:a“swiss army knife”approach to create a systemically delivered therapeutic

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signal Transduction and Targeted Therapy 2024年第5期9卷 1791-1792页

作者： Carolina s.Ilkow john Cameron Bell Ottawa Hospital Research Institute 501 Smyth RoadOttawaONK1H 8L6Canada

In a recent paper published in Nature Biotechnology,Chen et al.1 describe a multiplex oncolytic virus platform that coupled with adoptive T cell therapy could solve the problem of repeat,systemic delivery of virus based *** is widely accepted that multi-targeted therapeutic approaches attacking several facets of cancer biology are necessary to effectively deal with the tumor heterogeneity that exists within and between patients.

关键词： therapeutic al. targeted

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Evaluating reservoir suitability for large-scale hydrogen storage:A preliminary assessment considering reservoir properties

Energy Geoscience

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Energy Geoscience 2024年第4期5卷 198-211页

作者： Chinedu j.Okere james j.s.eng Chinedu Ejike Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityLubbockTX79409United States Mewbourne school of Petroleum and Geological Engineering University of OklahomaOK73019United States

With rising demand for clean energy,global focus turns to finding ideal sites for large-scale underground hydrogen storage(UHs)in depleted petroleum reservoirs.A thorough preliminary reservoir evaluation before hydrogen(H_(2))injection is crucial for UHs success and *** criteria for UHs often emphasize economics and chemistry,neglecting key reservoir *** study introduces a comprehensive framework for the reservoir-scale preliminary assessment,specifically tailored for long-term H_(2) storage within depleted gas *** evaluation criteria encompass critical components,including reservoir geometry,petrophysical properties,tectonics,and formation *** illustrate the practical application of this approach,we assess the Barnett shale play reservoir *** assessment unfolds through three key stages:(1)A systematic evaluation of the reservoir's properties against our comprehensive screening criteria determines its suitability for H_(2) storage.(2)Using both homogeneous and multilayered gas reservoir models,we explore the feasibility and efficiency of H_(2) *** phase involves an in-depth examination of reservoir behavior during the injection stage.(3)To enhance understanding of UHs performance,sensitivity analyses investigate the impact of varying reservoir dimensions and injection/production *** findings reveal the following:(a)Despite potential challenges associated with reservoir compaction and aquifer support,the reservoir exhibits substantial promise as an H_(2) storage site.(b)Notably,a pronounced increase in reservoir pressure manifests during the injection stage,particularly in homogeneous reservoirs.(c)Furthermore,optimizing injection-extraction cycle efficiency can be achieved by augmenting reservoir dimensions while maintaining a consistent *** ensure a smooth transition to implementation,further comprehensive investigations are advised,including experimental and numerical studies to address

关键词： site selection Underground hydrogen storage Preliminary evaluation Depleted petroleum reservoirs Reservoir assessment

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First Application of Optically Active trans-1,2-Bis(2- aminophenyl)cyclopentane for Asymmetric Reaction: Enantioselective N-Acetylation of secondary Alkyl Amines

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Chinese Chemical Letters 2001年第1期12卷 1-4页

作者： Yang j.s. Kondo K. Murakami Y. Dept. of Chem. of Med. Nat. Products School of Pharmacy W. China Univ. of Medical Sciences Chengdu 610041 China school of Pharmaceutical sciences Toho University Miyama 2-2-1 Funabashi Chiba 274 Japan

First application of optically active trans-1,2-Bis(2-aminophenyl)cyclopentane 2 for asymmetric reaction, enantioselective N-acetylation of secondary alkyl amines, is described. This acetylation with tetraacetylated 3... 详细信息

关键词： First Application of Optically Active trans-1,2-Bis Enantioselective N-Acetylation of secondary Alkyl Amines

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On the Geometry of the Anti-canonical Bundle of the Bott–samelson–Demazure–Hansen Varieties

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Acta Mathematica sinica,English series 2024年第8期40卷 1920-1940页

作者： Indranil BIsWAs s.senthamarai KANNAN Pinakinath sAHA school of Mathematics Tata Institute of Fundamental Research1 Homi Bhabha RoadMumbai 400005India Chennai Mathematical Institute Plot H1SIPCOT IT ParkSiruseriKelambakkam603103India

Let G be a semi-simple simply connected algebraic group over the field C of complex *** T be a maximal torus of G,and let W be the Weyl group of G with respect to *** Z(w,i)be the Bott–samelson–Demazure–Hansen variety corresponding to a tuple i associated to a reduced expression of an element w∈*** prove that for the tuple i associated to any reduced expression of a minuscule Weyl group element w,the anti-canonical line bundle on Z(w,i)is globally *** consequence,we prove that Z(w,i)is weak *** that G is a simple algebraic group whose type is different from *** s={α1,...,αn}be the set of simple *** w be such that support of w is equal to *** prove that Z(w,i)is Fano for the tuple i associated to any reduced expression of w if and only if w is a Coxeter element and w^(−1)(Σ_(t=1)^(n)α_(t))∈−s.

关键词： Bott-samelson-Demazure-Hansen variety Coxeter element anti-canonical line bundle Fano weak Fano

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surface Modification Aspects for Improving Biomedical Properties in Implants:A Review

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Acta Metallurgica sinica(English Letters) 2024年第2期37卷 213-241页

作者： j.s.arath Kumar Rakesh Kumar Rajeev Verma Industrial and Production Department Dr B R Ambedkar National Institute of Technology JalandharJalandharPunjab144008India

The primary focus during surgery is to ensure successful implantation by achieving long-term and stable fixation of *** surgery is now more focused on the development of novel biomaterials intended to improve implant *** obtain a better understanding of metal implants,this article investigated the causes of material failures in certain cases and analysed a few case *** interaction between the implant and bone tissue was a crucial aspect of successful implantation,and this study explored the factors influencing this interaction as well as ways to improve *** modern approaches used for modifying implant surfaces were systematically illustrated and briefly *** spray coatings were often favoured because of their wide range of coating materials,but other substantial surface modifications(such as friction stir processing and laser surface texturing)were also used for a selection of ***,implant surfaces with desirable features,such as biocompatibility,antibacterial properties,corrosion resistance,and wear resistance,were essential for optimising implant *** systematic review's main aim is to provide exhaustive reference information and a broad overview to advance the production and design of orthopaedic implants.

关键词： Biomaterials surface treatments Thermal spray coatings Antibacterial Biocompatibility Corrosion resistance Wear resistance

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Influence of Carrier Gas on Analysis of MgO Powders by Laser Ablation Inductively Coupled Plasma Mass spectrometry

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journal of Materials science & Technology 2009年第3期25卷 333-335页

作者： j.s. Lee Y.s. Lee C.j. Park H.s. Lee D.s. Lee Department of Chemistry Yonsei University Material Analysis Team Korea Testing Laboratory Korea Research Institute of standards and science school of Material science and Engineering Pusan National Univirsity

Laser ablation inductively coupled plasma mass spectrometry （LA-ICP-Ms） has been widely adopted for the direct multi-elemental analysis with high sensitivity. Especially analysis of fine ceramics by LA-ICP-Ms without time-consuming sample decomposition process has been one of the most expecting application field. small additive elements in MgO powders were analyzed by LA-ICP-Ms. For precise and accurate analysis influence of carrier gas （Ar or He） was presented by the signal intensities of ICP-Ms, relative standard deviation of signal intensities and ablated particle size distribution. Ablated particles were collected and analyzed by scanning electron microscopy （sEM） to investigate the particle size distribution, and the ablated sample surface was examined by camscope. In He gas atmosphere, the signal was more stable than in Ar gas atmosphere. The signal intensity was higher in Ar than in He. Examination of ablated particles and sample surface reveals that more particles were generated in Ar atmosphere and the distribution of particle size was larger.

关键词： Laser ablation MgO powders Carrier gas ICP-Ms

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Accuracy details in realistic CFD modeling of an industrial centrifugal pump in direct and reverse modes

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journal of Thermal science 2010年第6期19卷 491-499页

作者： j.C. Páscoa F. j. silva j.s. Pinheiro D.j. Martins Department of Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior EFAFLU Bombas e Ventiladores s.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of the flowfield inside a pump is herein used as a numerical laboratory, subject to the limitations of modeling assumptions and to experimental verification. A numerical computation of the flow inside a real industrial centrifugal pump is performed that includes a very sophisticated geometry. Conversely to other computations, in this test case no simplification of the geometry was introduced. Numerical computations are obtained using spalart-Allmaras turbulence model. A detailed analysis of the turbulent flowstructure is performed for the design point and two off design conditions. Additional computations were performed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. Further computations are presented for the pump working in reverse turbine mode (PAT). Detailed analyses of the flow allow a comparison of the internal flow losses when the pump is operating in direct and reverse mode. This is also useful to help in the selection of an adequate pump geometry that can work in both modes with best efficiency.

关键词： centrifugal pump impeller turbulence modeling spalart-Allmaras PAT

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