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Carbon quantum dots modified TiO_(2) composites for hydrogen production and selective glucose photoreforming

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Journal of Energy Chemistry 2022年第1期31卷 201-208,I0006页

作者： Heng Zhao Xinti Yu Chao-Fan Li Wenbei Yu Aiguo Wang Zhi-Yi Hu steve larter Yu Li Md Golam Kibria Jinguang Hu Department of Chemical and Petroleum Engineering University of Calgary2500 University DriveNWCalgaryAlberta T2N 1N4Canada State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina Nanostructure Research Centre Wuhan University of Technology.Wuhan 430070Hubei.China Department of Geosciences University of Calgary2500 University DriveNWCalgaryAlberta T2N 1N4Canada

Lignocellulosic biomass photoreforming is a promising and alternative strategy for both sustainable H_(2) production and biomass valorization with infinite solar ***,harsh reaction conditions(high alkalinity or toxic organic solvents),with low biomass conversion and selectivity are often reported in *** this work,we report glucose photoreforming for coproduction of H_(2) and arabinose with improved selectivity under neutral condition using carbon quantum dots(CQDs)modified TiO_(2) *** show that the conventional CQDs fabricated by a facile one-step hydrothermal process could be endowed with novel color changing property,due to the particle aggregation under the regulation of incident *** as-fabricated CQDs/TiO_(2) composites with certain colored CQDs could greatly improve glucose to arabinose conversion selectivity(-75%)together with efficient hydrogen evolution(up to 2.43 mmolh^(-1)g^(-1))in *** arabinose is produced via the direct C1-C2 α-scissions mechanism with reactive oxygen species of·O_(2)^(-) and·OH,as evidenced by ^(13)C labeled glucose and the electron spin-resonance(ESR)studies,*** work not only sheds new lights on CQDs assisted photobiorefinery for biomass valorization and H_(2) coproduction,but also opens the door for rationale design of different colored CQDs and their potential applications for solar energy utilization in the noble-metal-free system.

关键词： CQDs Size regulation Hydrogen production Glucose photoreforming Arabinose

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次生生物气的形成及其地球化学特征

次生生物气的形成及其地球化学特征

Digital neuromorphic technology: current and future prospects

第十届全国有机地球化学学术会议

作者：黄海平 163.cpom) steve larter 中国地质大学(北京)能源学院 Department of Geology and Geophysics University of Calgary844 Campus Place NorthwestCalgaryAB T2N 1N4Canada

＜正＞原油生物降解主要是在厌氧条件下进行的.烃类被细菌氧化分解形成二氧化碳,而二氧化碳又被产甲烷菌还原形成甲烷,这一过程中形成的甲烷气称为次生生物气。本文通过对辽河盆地生物降解油田一组原油伴生气的化学组成和碳、氢同位素...

＜正＞原油生物降解主要是在厌氧条件下进行的.烃类被细菌氧化分解形成二氧化碳,而二氧化碳又被产甲烷菌还原形成甲烷,这一过程中形成的甲烷气称为次生生物气。本文通过对辽河盆地生物降解油田一组原油伴生气的化学组成和碳、氢同位素分析,结合相关原油的地质、地球化学特征,把天然气分为生物降解气和未降解气两类。生物降解气的特征表现为:干燥系数高

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National Science Review 2024年第5期11卷 10-11页

作者： steve Furber Department of Computer Science The University of Manchester

Neuromorphic technology has diversified considerably from its origins in the seminal work by Carver Mead and his group at Caltech in the 1980s [1]. That early work focussed on the analogy between the equations describing the flow of ions in biological neurons and the equations describing the flow of carriers in field-effect transistors operating in the subthreshold region.

关键词： technology current future digital neuromorphic prospects

Modern Black Sea oceanography applied to the end-Permian extinction event

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Journal of Palaeogeography 2015年第1期4卷 52-62页

作者： steve Kershaw Institute for the Environment Health and Societies Brunel UniversityKingston LaneUxbridge Middlesex UB8 3PH UK

The modern Black Sea has a mixed upper layer in the top 150-200 m of the water column, below which the water is anoxic, separated from the mixed layer by a redox boundary. There is limited vertical movement of water. Pyrite framboids form in the water column of the anoxic zone, then have been traditionally interpreted to sink immediately and accumulate in the sediments of the Black Sea. Thus the occurrence of framboids in sediments in the rock record is widely interpreted to indicate poorly oxygenated to anoxic conditions in ancient environments. However, in the Permian-Triassic boundary （PTB） microbialites of South China, which formed in shallow marine conditions in contact with the atmosphere, the published occurrence of framboids is inconsistent with abundant gastropod and ostracod shells in the microbialite. Furthermore, in the modern Black Sea, （a） framboids may be suspended, attached to organic matter in the water column, thus not settle to the sea floor immediately after formation; and （b） the redox zone is an unstable complex area subject to rapid vertical water movement including occasional upwelling. The model presented here supposes that upwelling through the redox zone can lead to upward transport of suspended pyrite framboids into the mixed layer. Advective circulation could then draw suspended framboids onto the shelf to be deposited in oxygenated sediments. In the Permian-Triassic transition, if framboids were upwelled from below the redox boundary and mixed with oxygenated waters, sediment deposited in these conditions could provide a mixed signal for potentially misleading interpretations of low oxygen conditions. However, stratigraphic sampling resolution of post-extinction microbialites is currently insufficient to demonstrate possible separation of framboid-bearing layers from those where framboids are absent. Profound differences between microbialite constructors and sequences between the western and eastern Tethys demonstrate barriers to migra

关键词： mass extinction Permian-Triassic boundary microbialite ostracods gastro-pods anoxia Black Sea

Improving reflectance estimation by BRDF-consistent region clustering

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Progress in Natural Science:Materials International 2006年第3期16卷 313-320页

作者： LIN steve Beijing 100080 China Visual Computing Group Microsoft Research Asia

Previous studies in reflectance estimation generally require prior segmentation of an image into regions of uniform reflectance. Due to the measurement noise and limited sampling of the BRDF (bi-directional reflectance function) directions, such estimated results of reflectance are not accurate. In this paper, we propose a novel method for reducing uncertainty in reflectance estimates by merging image regions which have consistent reflectance observations. Each image region acts as a reflectance subspace, so merging of the image regions can result in subspace reduction. We propose a Bayesian segmentation framework to decrease the reflectance uncertainty by using novel merging criteria. Finally, a maximum likelihood reflectance estimation is made for each resulting image region. Experimental results verify the feasibility and superiority of this reflectance-oriented region merging method.

关键词： texture shading grouping and segmentation reflectance estimation BRDF uncertainty.

Quantitative Absolute Continuity of Harmonic Measure and the Dirichlet Problem: A Survey of Recent Progress

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Acta Mathematica Sinica,English Series 2019年第6期35卷 1011-1026页

作者： steve HOFMANN Department of Mathematics University of Missouri

It is a well-known folklore result that quantitative, scale invariant absolute continuity(more precisely, the weak-A∞ property) of harmonic measure with respect to surface measure, on the boundary of an open set Ω ? R^(n+1) with Ahlfors–David regular boundary, is equivalent to the solvability of the Dirichlet problem in Ω, with data in L^p (?Ω) for some p < ∞. Drawing an analogy to the famous Wiener criterion, which characterizes the domains in which the classical Dirichlet problem, with continuous boundary data, can be solved, one may seek to characterize the open sets for which L^psolvability holds, thus allowing for singular boundary *** has been known for some time that absolute continuity of harmonic measure is closely tied to rectifiability properties of ?Ω, but also that rectifiability alone is not sufficient to guarantee absolute continuity. In this note, we survey recent progress in this area, culminating in a geometric characterization of the weak-A∞ property, and hence of solvability of the L^p Dirichlet problem for some finite p. This characterization, obtained under rather optimal background hypotheses, follows from a combination of the present author's joint work with Martell, and the work of Azzam, Mourgoglou and Tolsa.

关键词： Harmonic measure Poisson kernel uniform rectifiability weak local John condition big pieces of chord-arc domains Carleson measures

Underground mine stream crossing assessment:A multi-disciplinary approach

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International Journal of Mining Science and Technology 2021年第1期31卷 59-65页

作者： Kevin Andrews steve Keim Marshall Miller&Associates BluefieldVA 24605USA

Underground mine designs typically try to avoid extraction beneath streams and rivers of any significant size,especially when the overburden rock thickness between the stream bed and the mine is *** issues with mining beneath streams include excessive groundwater inflow to the mine,weak ground(roof,floor,and pillar)conditions,horizontal stress effects,as well as stream loss and other potential adverse environmental ***,there are times when crossing beneath a stream or river is necessary to move into a new area of mineral reserve without creating additional mine access points from the ground ***,stream crossings are completed without thorough assessment,potentially resulting in increased costs,decreased safety,and,in some cases,failure to advance the *** of the most favorable location(s)to cross the stream must account for numerous factors and the associated assessment often requires a multi-disciplinary *** crossing investigations often require geological,hydrogeological,geotechnical,and geophysical *** of stream crossing investigations include desktop evaluation of maps and aerial photography,stream bed observations,drilling,detailed rock core logging,downhole geophysical surveying,hydraulic conductivity testing(packer testing),geotechnical laboratory testing,assessment,and *** deliverables from a stream crossing assessment typically include geological,geotechnical,and hydrogeological characterization of potential stream crossing locations,classification of favorable and unfavorable crossing locations,recommendations for entry design and pillar sizing,and recommendations for if,and how,to conduct pre-grouting *** of technical aspects of data collection and assessment are provided based on decades of industry experience conducting stream crossing assessments in various underground mining scenarios.

关键词： Underground mining Geotechnical Stream-crossing Hydrogeology Characterization

Green spermatozoa illuminate a 30-year-old model： sperm-egg adhesion involves intra-acrosomal proteins

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Asian Journal of Andrology 2011年第5期13卷 665-666页

作者： steve Tardif Reproductive and Developmental Biology Group Centrefor Oncology and Molecular Medicine Division ofMedical Sciences Ninewells Hospital University ofDundee Dundee Scotland DD1 9SY UK

Fertilisation in mammals involves many synchronized steps including spermegg adhesion. Prior to sperm-oolemma fusion, spermatozoa need to undergo the acrosome reaction （AR） or exocytosis. The universal belief, for many years, has been that the AR was initiated upon binding to the zona pellucida （ZP）. As such acrosomal proteins were not thought to be involved in the primary contact with the ZP. These proteins were only suggested to be biologically relevant once the sperm were attached to the ZP and during subsequent events. However,

关键词： Green reexamination

A Subjective Risk Analysis Approach of Container Supply Chains

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International Journal of Automation and computing 2005年第1期2卷 85-92页

作者： steve Bonsall School of Engineering Liverpool John Moores University Liverpool L3 3AF UK

After the 9/11 terrorism attacks, the lock-out of the American West Ports in 2002 and the breakout of SARS disease in 2003 have further focused mind of both the public and industrialists to take effective and timely measures for assessing and controlling the risks related to container supply chains (CSCs). However, due to the complexity of the risks in the chains, conventional quantitative risk assessment (QRA) methods may not be capable of providing sufficient safety management information, as achieving such a functionality requires enabling the possibility of conducting risk analysis in view of the challenges and uncertainties posed by the unavailability and incompleteness of historical failure data. Combing the fuzzy set theory (FST) and an evidential reasoning (ER) approach, the paper presents a subjective method to deal with the vulnerability-based risks, which are more ubiquitous and uncertain than the traditional hazard-based ones in the chains.

关键词： Container supply chains risk assessment evidential reasoning fuzzy sets vulnerability