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3D CFD Simulation of Pulsatile Blood Flow in the Human Aorta

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Chinese Journal of Biomedical Engineering(English Edition) 2003年第4期12卷 174-183页

作者： Herbert Oertel jr. Lukas Zürcher Torsten Schenkel Institute of Fluid Mechanics University of KarlsruheInstitute of Fluid MechanicsUniversity of KarlsruheInstitute of Fluid MechanicsUniversity of Karlsruhe karlsruhe D-76128Germanykarlsruhe D-76128Germanykarlsruhe D-76128Germany

A three-dimensional computational fluid dynamics (CFD) simulation of the physiological pulsatile blood flow in the human aortic arch and its three branches has been conducted by using commercial software StarCD. The blood flow, of a peak Reynolds number of 3289 and a Womersley parameter of 16.44, was simulated in a rigid aorta geometry that was built by computer aided design (CAD) reconstruction method based on autopsy data of a female adult. The purpose of this work is to further the understanding of the complex nature of aorta flow, therefore it mainly focuses on analysis of the spatial and temporal distributions of velocities and wall shear stresses. The results, illustrated by 3D visualization pictures and 2D graphs of the primary velocity profiles, wall shear stress and pressure distributions, as well as the secondary flow patterns, are in good agreement with those of other experimental and computational works. The distributions of pressure and wall shear stress support the correlation between high and low shear stresses and pressures and the atherosclerotic lesions.

关键词： Hemodynamics Computational fluid dynamics The human aorta Pulsatile blood flow Simulation of flow field

Climate bonds toward achieving net zero emissions and carbon neutrality:Evidence from machine learning technique

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Journal of Management Science and Engineering 2024年第1期9卷 1-15页

作者： Hermas Abudu Presley K.Wesseh jr. Boqiang Lin College of Overseas Education Chengdu UniversityChengdu610106SichuanChina School of Management China Institute for Studies in Energy PolicyCollaborative Innovation Center for Energy Economics and Energy PolicyXiamen UniversityFujian361005China Center for African Development Strategy(CFADS) MonroviaLiberia

The Conference of the Parties(COP26 and 27)placed significant emphasis on climate financing policies with the objective of achieving net zero emissions and carbon ***,studies on the implementation of this policy proposition are *** address this gap in the literature,this study employs machine learning techniques,specifically natural language processing(NLP),to examine 77 climate bond(CB)policies from 32 countries within the context of climate *** findings indicate that“sustainability”and“carbon emissions control”are the most outlined policy objectives in these CB ***,the study highlights that most CB funds are invested toward energy projects(i.e.,renewable,clean,and efficient initiatives).However,there has been a notable shift in the allocation of CB funds from climate-friendly energy projects to the construction sector between 2015 and *** shift raises concerns about the potential redirection of funds from climate-focused investments to the real estate industry,potentially leading to the greenwashing of climate ***,policy sentiment analysis revealed that a minority of policies hold skeptical views on climate change,which may negatively influence climate ***,the findings highlight that the effective implementation of CB policies depends on policy goals,objectives,and ***,this study contributes to the literature by employing NLP techniques to understand policy sentiments in climate financing.

关键词： Climate bonds funds utilization Climate bonds policy text mining Machine learning technique Net zero emissions Policy sentiment analysis

C-H…X-C bonds in alkyl halides drive reverse selectivities in confined spaces

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Chinese Chemical Letters 2023年第5期34卷 237-240页

作者： Manuel Petroselli yong-Qing Chen Ming-Kai Zhao Julius Rebek jr. yang yu Center for Supramolecular Chemistry and Catalysis and Department of Chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research InstituteLa JollaCA 92037United States

Binding of non-activated alkyl halides(2-20)in water-soluble cavitand(1)through supramolecular forces is here reported,with emphasis on the role of size and polarizability of the halogen atom in the formation of intramolecular C-H hydrogen bonds in confined *** reverse affinity in water(RIy observed for the more water-soluble short alkyl halides in dynamic open-ended *** bindings and theoretical calculations confirm the unusual selectivity and the presence of C-H hydrogen bonds in non-activated systems for the first time,pointing out the importance and effect of subtle forces on molecular recognition in confined spaces.

关键词： Water-soluble cavitand Host-guest complex Molecular recognition C-H hydrogen bond Alkyl halides

pH-mediated synthesis of monodisperse gold nanorods with quantitative yield and molecular level insight

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Nano Research 2021年第4期14卷 1167-1174页

作者： Reese Gallagher Xing Zhang Anthony Altomare David Lawrence jr. Nicholas Shawver Ninh Tran Melanie Beazley Gang Chen Department of Chemistry University of Central FloridaOrlando32816USA

Although gold nanorods(GNRs)have been produced with different dimensions and aspect ratios,the current synthesis methods through seed-mediated growth are far from ideal,for instance,the quality(rod yield)and the quantity(gold conversion)cannot be simultaneously *** critically,there is no molecular level understanding of the growth ***,we solved the problem by employing the stoichiometric ratio of reactants and tuning the reactivity of the reductant through adjusting the initial pH value of the growth solution to achieve both good quality and high quantity *** also extended our strategy to other enols besides ascorbic acid,such as phenolic compounds,and found that the optimal pH for GNRs synthesis depends on the structure of the individual *** mechanistic insight greatly enriches the toolbox of reductants for GNRs growth and makes it possible to synthesize GNRs at both acidic and basic *** interesting phenomenon is that for most of the phenolic compounds we tested,the morphology of the final products follows the same sphere-rod-sphere trend as the initial pH value of the reaction increases,whether it is under acidic or basic conditions,which cannot be explained by any previously proposed *** effect of pH is mainly attributed to the regulation of the reduction potential of the reductants,and thus the reaction rate.A model has been proposed to explain the dependence of anisotropic growth of GNRs on the concentration gradient of reactants around the seeds,which is decided by both the reaction rate and diffusion rate.

关键词： gold nanorods gold conversion yield shape homogeneity pH value reduction potential concentration gradient

Cenozoic reactivation along the Late Triassic Ganzi-Litang suture,eastern Tibetan Plateau

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Geoscience Frontiers 2020年第3期11卷 1069-1080页

作者： W.T.Jackson jr. D.M.Robinson A.L.Weislogel X.Jian Department of Earth Sciences University of South AlabamaMobileAL36688USA Department of Geological Sciences and Center for Sedimentary Basin Studies The University of AlabamaTuscaloosaAL35487USA Department of Geography and Geology West Virginia UniversityMorgantownWV26506USA State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China

The spatial-temporal development of Cenozoic reactivation along Mesozoic suture zones in the Tibetan Plateau are first-order parameters needed for assessing models of plateau *** Ganzi-Litang suture,in the eastern Tibetan Plateau,developed in the Late Triassic because of subduction and closure along the eastern branch of the Paleo-Tethys *** the city of Litang,the Ganzi-Litang suture is defined by a melange sequence with faultbound,synorogenic nonmarine strata along the western and eastern flanks,suggesting post-Triassic structural *** present detrital zircon U-Pb geochronology and field data to determine the timing and style of reactivation along the Ganzi-Litang suture,as well as sedimentary provenance of nonmarine strata.A reverse fault placing melange rock on top of nonmarine strata along the eastern flank of the Ganzi-Litang suture indicates a contractional deformational regime during *** clast counts indicate a local sediment source of recycled Ganzi-Litang suture and yidun terrane *** zircons indicate a localized provenance consisting of recycled material from Triassic yidun Arc plutons and Triassic yidun Group turbidite rock.A weighted mean average of Cenozoic zircon grains(n=10) establishes a maximum depositional age of41.5 ± 1.2 Ma for nonmarine strata in the Ganzi-Litang *** interpret the maximum depositional age of the nonmarine strata to represent the upper-limit for structural reactivation along the Ganzi-Litang suture while undeformed Neogene strata in the suture zone represent the lower-limit;thereby bracketing structural reactivation from ca.42-25 *** results provide enhanced spatial-temporal resolution for Cenozoic deformation in the eastern Tibetan Plateau.

关键词： Nonmarine strata yidun terrane Tibetan plateau Zircon Suture zone Reactivation

SnRK1a1, a new player in the sucrose-Opaque2 network during endosperm filling

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Molecular Plant 2024年第8期17卷 1172-1174页

作者： Kelly Mayrink Balmant Marcio F.R.Resende jr. Horticultural Sciences Department University of FloridaGainesvilleFLUSA

Maize(Zea mays)endosperm is an important food source for humans and *** addition,it is considered an excellent model for research on seed development because of its relatively large size for both embryo and endosperm compared to those of other crop species,such as rice(Oryza sativa)and wheat(Triticum aestivum).After double fertilization,early maize endosperm development includes three stages:(i)a multinucleate coenocyte stage;(i)a cellularization stage,in which the cellular endosperm is formed;and(ii)a stage of differentiation into distinct *** early differentiation,four major cell types with specific functions differentiate within the endosperm:starchy endosperm,aleurone layer,basal endosperm transfer layer(BETL),and embryo surrounding *** subaleurone,conducting zone,basal intermediate zone,and endosperm adjacent to scutellum arise in late differentiation(Sabelli and Larkins 2009).After the main cell types are established,maize endosperm undergoes intensive cell proliferation,which marks the transition to the endosperm-filling *** the endosperm-flling stage,the maternal sucrose products are transported to seeds through the BETL region,where they will act as the main carbon substrate for storage products such as starch and proteins(Chen et al.,2023).In fact,the endosperm of maize seeds accounts for approximately 90%of the total grain weight,serving as an important nutrient reservoir(Flint-Garcia et al.,2009).

关键词： endosperm reservoir Flint

ADVANCES IN LIQUID CRySTALLINE POLyESTERS

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Chinese Journal of Polymer Science 1992年第3期10卷 195-202页

作者： W. J. Jackson jr. Research Laboratories Eastman Chemical Company Eastman Kodak Company Kingsport Tennessee U.S.A.Research Laboratories Eastman Chemical Company Eastman Kodak Company Kingsport Tennessee U.S.A.

Advances have been made in understanding the interactions of composition, molecular weight, liquid crystallinity,orientation, and three-dimensional crystallinity on the properties of injection-molded and melt-spun liquid crystalline polyesters (LCP's). Two classes of potentially low-cost LCP's were compared:(1) semiflexible LCP's prepared from 1,6-hexanediol and the dimethyl ester of either trans-4, 4'stilbenedicarboxylic acid or 4.4 ' biphenyldicarboxylic acid and (2) all-aromatic LCP's prepared from terephthalic acid, 2, 6-naphthalenedicarboxylic acid, the diacetate of hydroquinone, and the acetate of p-hydroxybenzoic acid. The effects of composition on the plastic properties of the 4-component all-aromatic LCP's were determined with the aid of a 3 x 3 factorial statistically designed experiment, the generation of equations with a computer program, and the plotting of three-dimensional figures and contour diagrams. The effects of absolute molecular weight (M_w) on the tensile strengths of the semiflexible LCP's and one of the all-aromatic LCP's having an excellent balance of plastic properties were also compared, and it was observed that the semiflexible LCP's required M_w's about 4 times higher than the all-aromatic LCP to attain a given strength. Persistence lengths and molecular modeling were used to explain these differences.

关键词： Liquid crystal thermotropic polyester plastic properties

Self-assembled hexameric capsule:A highlyβ-selective O-glycosylation reaction enabled via proton wire mechanism

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Green Synthesis and Catalysis 2023年第1期4卷 7-9页

作者： Kuppusamy Kanagaraj Julius Rebek jr. yang yu Center for Supramolecular Chemistry&Catalysis and Department of Chemistry College of ScienceShanghai UniversityShanghai200444China The Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research InstituteLa JollaCA 92037United States

A simple methodology has been developed for the synthesis of highlyβ-selective O-glycosylation scaffolds of wider substrate scope under mild conditions using a self-assembled hexameric *** reaction conditions are compatible with a wide range of functional *** control experiments and theoretical studies established that the reaction takes place inside the capsule *** substrates are activated via a proton wire as seen in some enzymes,and the reactions follow an SN2 pathway through a loose transition *** advantages of this methodology are selectivity,high yields and scalability;the catalyst is readily recovered and *** methodology was adapted to the synthesis of mesomorphic glycosides and anti-tumour agents in short synthetic routes.

关键词： Capsule Self-assembly β-Selective glycosylation Synthetic receptor Proton wire mechanism

Synthesis of Benzothiazonine by Rhodium-catalyzed Denitrogenative Transannulation of 1-sulfonyl-1,2,3-triazole and Thiochromone

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Synthesis of Benzothiazonine by Rhodium-catalyzed Denitrogen...

作者： Jablasone jr. Saygbechi T. 浙江理工大学

学位级别：硕士

1-Sulfonyl-1,2,3-triazoles have emerged as an efficient source for the synthesis of nitrogen containing compounds through in situ generation ofα-*** document focuses on the construction of medium-size N,S-heterocycles which has an important role in pharmaceutics and drug *** procedure involving ring expansion can be made possible through a[6+3]cyclization reaction of 1,2,3-triazole with thiochromone to afford some medium N,S-heterocycles including benzothiazonine *** the basis of various experiments and investigations,it was found that when 1-Sulfonyl-1,2,3-triazole was treated with 5 mol%Rh（OAc） as catalyst under a nitrogen atmosphere and temperature of90 ~oC with toluene as solvent afforded the product at an almost quantitative *** development of synthetic methods for such a novel compound is of great significance in the field of synthetic organic chemistry and drugs discovery,owing to the fact that it involves the construction of a more challenging 9-membered ring containing sulfur and nitrogen *** the standard conditions,we successfully achieved the reaction of1-sulfonyl-1,2,3-triazole with Thiochromone through intermolecular sulfur ylide formation followed by ring expansion to enable the construction of renaissance 9-membered N,*** products could also be converted to some other derivatives containing medium-size N,S-heterocycles,illustrating the potential of this protocol in organic synthesis.

关键词： 1-Sulfonyl-1, 2,3-Triazole Carbene Benzothiazonine, [6+3] Cyclization