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NHC-mediated photocatalytic para-selective C–H acylation of aryl alcohols: regioselectivity control via remote radical spiro cyclization

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Science China Chemistry 2025年

作者： Tinglei Zhang Lala Wang Xiaolin Peng Tianhui Liao Dongmei Chen Ting Tu Donghan Liu Ziye Cheng Shiqing Huang Shi-Chao ren Xinglong Zhang Yonggui robin Chi State Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Qiannan Medical College for Nationalities School of Chemistry Chemical Engineering and Biotechnology Nanyang Technological University Department of Chemistry The Chinese University of Hong Kong Institute of High Performance Computing Agency for Science Technology and Research

Friedel-Crafts reaction and transition-metal catalysis represent primary methodologies for arene acylation; however, suffer from certain limitations, such as electronic effect-dependent reactivity, regioselectivity issues, the necessity of directing group, and relatively exceptionally limited exploration in meta-and para-acylations. N-heterocyclic carbene(NHC) catalysis has recently emerged as a promising alternative strategy for arene acylation, offering distinct regioselectivity profiles that are challenging to achieve through known methods. Herein, an NHC-mediated photo-catalytic para-selective C–H acylation of aryl alcohols is disclosed. The reaction employs a remote radical-induced temporary spiro cyclization strategy, proceeding via tandem radical dearomatization, radical acylation, rearomatization processes. Combined experimental and computational mechanistic studies support the proposed reaction pathway and observe an exclusive para-selectivity regardless of the nature of the substituents on the substrates. Despite the less satisfactory yields, the current method exhibits non-electronic nature-based reactivity and regioselectivity, enabling quick access to acylated arenes that are difficult or impossible for reported methods.

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Optimal control of a hybrid microgrid for hydrogenbased heat supply using deep reinforcement learning

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Clean Energy 2023年第5期7卷 940-951页

作者： robin Heckmann Faculty of Computer Science University of Library Studies and Information Technologies119Tsarigradsko shosse Blvd1784SofiaBulgaria

Green hydrogen is considered one of the key technologies of the energy transition,as it can be used to store surpluses from renewable energies in times of high solar radiation or wind speed for use in dark *** paper examines the decarbonization potential of hydrogen for the heating ***,99%of hydrogen is produced from fossil fuels,because hydrogen derived from renew-able energy sources remains prohibitively expensive compared with its conventional ***,due to the expansion of renewable energy sources and the current energy crisis of conventional energy sources,hydrogen from renewable energy sources is becoming more and more *** optimize the efficiency of green hydrogen production and make it more price-competitive,the author simulates a hydrogen production plant consisting of a photovoltaic plant,a power grid,hydrogen storage,an electro-lyser,a natural gas purchase option,a district heating plant and *** the deep deterministic policy gradient algorithm from deep reinforcement learning,the plant is designed to optimize itself by simulating different production scenarios and deriving *** connected district heating plant is used to map how hydrogen can be optimally used for heat supply.A demonstrable outcome of this paper is that the utilization of deep deterministic policy gradient,over the course of a full year,can result in a com-petitive production of hydrogen derived from renewable or stored energy sources for the heating industry as a natural gas substitute.

关键词： hydrogen renewable energy hybrid microgrid deep reinforcement learning deep deterministic policy gradient

Color and behavior differently predict competitive outcomes for divergent stickleback color morphs

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Current Zoology 2018年第1期64卷 115-123页

作者： robin M. TINGHITELLA Whitley r. LEHTO V. Faith LIErHEIMEr Department of Biological Sciences University of Denver 2199 S. University Blvd Denver CO 80208 USA

Our knowledge of how male competition contributes to speciation is dominated by investigations of competition between within-species morphs or closely related species that differ in conspicuous traits expressed during the breeding season （e.g. color, song）. In such studies, it is important to consider the manner in which putatively sexually selected traits influence the outcome of competitive interactions within and between types because these traits can communicate information about competitor quality and may not be utilized by homotypic and heterotypic receivers in the same way. We studied the roles of breeding color and aggressive behaviors in competition within and between two divergent threes- pine stickleback Gasterosteus aculeatus color types. Our previous work in this system showed that the switch from red to black breeding coloration is associated with changes in male competition biases. Here, we find that red and black males also use different currencies in competition. Winners of both color types performed more aggressive behaviors than losers, regardless of whether the competitor was of the same or opposite color type. But breeding color differently predicted competitive outcomes for red and black males. Males who were redder at the start of competition were more likely to win when paired with homotypic competitors and less likely to win when paired with heterotypic competitors. In contrast, black color, though expressed in the breeding season and condition dependent, was unrelated to competitive outcomes. Placing questions about the role of male competition in speciation in a sexual signal evolution framework may provide insight into the ＂why and how＂ of aggression biases and asymmetries in competitive ability between closely related morphs and species.

关键词： male competition speciation sexual signal color threespine stickleback Gasterosteus aculeatus

Identification of fungal fossils and novel azaphilone pigments in ancient carbonised specimens of Hypoxylon fragiforme from forest soils of Chatillon-sur-Seine(Burgundy)

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Fungal Diversity 2018年第5期92卷 345-356页

作者： Frank Surup Abolfazl Narmani Lucile Wendt Sebastian Pfutze robin Kretz Kevin Becker Cle ment Menbrives Alain Giosa Michelle Elliott Christophe petit Manfred rohde Marc Stadler Dept.Microbial Drugs Helmholtz-Zentrum für Infektionsforschung GmbHInhoffenstrasse 738124 BraunschweigGermany German Centre for Infection research(DZIF) Partner Site Hannover-Braunschweig38124 BraunschweigGermany Department of Plant Protection Faculty of AgricultureUniversity of TabrizTabrizIran University of Paris 1 Panthéon-Sorbonne UMR 7041Archéologies EnvironnementalesParisFrance Helmholtz-Zentrum für Infektionsforschung GmbH Central Facility for MicroscopyInhoffenstrasse 738124 BraunschweigGermany

Fungal stromata were recently discovered in association with charcoal and burnt soil aggregates during an archaeological survey in the Chaˆtillon-sur-Seine forest *** wood and soil in the samples were dated to the medieval period(between 738 and 1411 AD).Light microscopy and scanning electron microscopy revealed that a few of the stromatal fragments still contained *** macromorphological characters were described and secondary metabolite profiles were generated using high performance liquid chromatography with diode array and mass spectrometric detection(HPLC–DAD/MS).The combination of these two data lines then allowed species *** of the fragments were assigned to Hypoxylon fragiforme,the type species of the Hypoxylaceae(Xylariales).Two further species whose stromata grew on the fossil charcoal could be tentatively identified as Jackrogersella cohaerens and(more tentatively)as Hypoxylon *** three species are still commonly encountered in the forests of Central Europe ***,the HPLC-HrMS data of *** suggested the presence of unknown azaphilone dimers and of further new *** archaeological compounds were compared to fresh stromata of *** collected in Germany and subjected to the same analytical *** the major components in both samples were identified as the known mitorubrin type azaphilones and orsellinic acid,the chemical structures of seven novel complex azaphilone pigments,for which we propose the trivial names rutilins C-D and fragirubrins A-E,were elucidated using spectral methods(NMr and CD spectroscopy,high resolution mass spectrometry).It appears that these pigments had indeed persisted for millennia in the fossil stromata.

关键词： Biodiversity Chemotaxonomy Phylogeny Sordariomycetes Xylariales Structure elucidation

THE VACUUM IN NONISENTrOPIC GAS DYNAMICS

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Acta Mathematica Scientia 2012年第1期32卷 339-351页

作者： Geng Chen robin Young Department of Mathematics Pennsylvania State University University Park PA 16802 USA Department of Mathematics University of Massachusetts Amherst MA 01003 USA

We investigate the vacuum in nonisentropic gas dynamics in one space vari- able, with the most general equation of states allowed by thermodynamics. We recall physical constraints on the equations of state and give explicit and easily checkable conditions under which vacuums occur in the solution of the riemann problem. We then present a class of models for which the riemann problem admits unique global solutions without vacuums.

关键词： nonisentropic gas dynamics conservation laws vacuum large data riemann problem

An Ontology Based Cyclone Tracks Classification Using SWrL reasoning and SVM

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Computer Systems Science & Engineering 2023年第3期44卷 2323-2336页

作者： N.Vanitha C.r.rene robin D.Doreen Hephzibah Miriam Sri Sai ram Engineering College Chennai600044TamilnaduIndia Director of Computational Intelligence research Foundation Chennai600023TamilnaduIndia

Tropical cyclones(TC)are often associated with severe weather conditions which cause great losses to lives and *** precise classification of cyclone tracks is significantly important in thefield of weather *** this paper we propose a novel hybrid model that integrates ontology and Support Vector Machine(SVM)to classify the tropical cyclone tracks into four types of classes namely straight,quasi-straight,curving and sinuous based on the track *** Cyclone Tracks Ontology(TCTrO)described in this paper is a knowledge base which comprises of classes,objects and data properties that represent the interaction among the TC characteristics.A set of SWrL(Semantic Web rule Language)rules are directly inserted to the TCTrO ontology for reasoning and inferring new knowledge from ***,we propose a learning algorithm which utilizes the inferred knowledge for optimizing the feature *** to experiments on the IBTrACS dataset,the proposed ontology based SVM classifier achieves an accuracy of 98.3%with reduced classification error rates.

关键词： Tropical cyclones classification support vector machine ontology SWrL reasoning SVM classification

LINEAr WAVES THAT EXPrESS THE SIMPLEST POSSIBLE PErIODIC STrUCTUrE OF THE COMPrESSIBLE EULEr EQUATIONS

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Acta Mathematica Scientia 2009年第6期29卷 1749-1766页

作者： Blake Temple robin Young Department of Mathematics University of California Davis CA 95616 USA Department of Mathematics and Statistics University of Massachusetts Amherst MA 01003 USA

In this paper we show how the simplest wave structure that balances compression and rarefaction in the nonlinear compressible Euler equations can be represented in a solution of the linearized compressible Euler equations. Such waves are exact solutions of the equations obtained by linearizing the compressible Euler equations about the periodic extension of two constant states separated by entropy jumps. Conditions on the states and the periods are derived which allow for the existence of solutions in the Fourier 1-mode. In [3, 4, 5] it is shown that these are the simplest linearized waves such that, for almost every period, they are isolated in the kernel of the linearized operator that imposes periodicity, and such that they perturb to nearby nonlinear solutions of the compressible Euler equations that balance compression and rarefaction along characteristics in the formal sense described in [3]. Their fundamental nature thus makes them of interest in their own right.

关键词： compressible Euler periodic solutions conservation laws

Mapping urban building stocks for vulnerability assessment preliminary results

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International Journal of Digital Earth 2011年第S1期4卷 117-130页

作者： Keiko Saito robin Spence Department of Architecture University of CambridgeCambridgeUK Cambridge Architectural research Ltd CambridgeUK Willis research Fellow Willis Research Network

This paper discusses a methodology to collect building inventory data by combining image processing techniques,field work or tools such as Google Street View and applying statistical *** the methodology outlined in Marinescu(2002),a family of Gabor filters are first constructed,which are then applied to an optical high-resolution *** output from the processed image is segmented using Self-Organising *** paper examines the relationship between the segmented areas in the image and the building type distribution within each segmented area,by deriving the distribution from field *** relationship between the average number of buildings in these cells against the number of grid cells allocated to each segmentation cluster is also ***,using these results,the overall building inventory distribution for the whole of the case study site of Pylos is presented.

关键词： building inventory data collection remote sensing high-resolution optical satellite images Gabor filters Self-Organising Maps field data

Pathophysiology of cerebral oedema in acute liver failure

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World Journal of Gastroenterology 2013年第48期19卷 9240-9255页

作者： Teresa r Scott Victoria T Kronsten robin D Hughes Debbie L Shawcross Institute of Liver Studies King’s College London School of Medicine at King’s College Hospital King’s College Hospital London SE5 9RS United Kingdom

Cerebral oedema is a devastating consequence of acute liver failure(ALF)and may be associated with the development of intracranial hypertension and *** ALF,some patients may develop cerebral oedema and increased intracranial pressure but progression to lifethreatening intracranial hypertension is less frequent than previously described,complicating less than one third of cases who have proceeded to coma since the advent of improved clinical *** rapid onset of encephalopathy may be dramatic with the development of asterixis,delirium,seizures and *** and vasogenic oedema mechanisms have been implicated with a preponderance of experimental data favouring a cytotoxic *** swelling is the most consistent neuropathological finding in humans with ALF and ammonia plays a definitive role in the development of cytotoxic brain *** mechanism(s)by which ammonia induces astrocyte swelling remains unclear but glutamine accumulation within astrocytes has led to the osmolyte *** evidence also supports an alternate‘Trojan horse’hypothesis,with glutamine as a carrier of ammonia into mitochondria,where its accumulation results in oxidative stress,energy failure and ultimately astrocyte *** a complete breakdown of the blood-brain barrier is not evident in human ALF,increased permeation to water and other small molecules such as ammonia has been demonstrated resulting from subtle alterations in the protein composition of paracellular tight *** present,there is no fully efficacious therapy for cerebral oedema other than liver transplantation and this reflects our incomplete knowledge of the precise mechanisms underlying this process which remain largely unknown.

关键词： Cerebral oedema Acute liver failure Ammonia Hepatic encephalopathy Intracranial pressure Intracranial hypertension Cerebral blood flow