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Host–Guest Molecular Recognition at Liquid–Liquid Interfaces

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Engineering 2021年第5期7卷 603-614页

作者： Beibei Wang Hao Chen Tan Liu Shaowei Shi thomas p.Russell Beijing Advanced Innovation Center for Soft Matter Science and Engineering College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Department of polymer Science and Engineering University of MassachusettsAmherstMA 01003USA Materials Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Host–guest molecular recognition at the liquid–liquid interface endows the interface with unique properties,including stimuli-responsiveness and self-regulation,due to the dynamic and reversible nature of non-covalent *** research efforts have been put into the preparation of supramolecular interfacial systems such as films and microcapsules by integrating functional components(e.g.,colloidal particles,polymers)at the interface,providing tremendous opportunities in the areas of encapsulation,delivery vehicles,and biphasic reaction *** this review,we summarize recent progress in supramolecular interfacial systems assembled by host–guest chemistry,and provide an overview of the fabrication process,functions,and promising applications of the resultant constructs.

关键词： Liquid-liquid interface Self-assembly Host-guest chemistry Microcapsules

Tungsten promoted Ni/Al_2O_3 Catalysts for Carbon Dioxide Reforming of Methane to Synthesis Gas

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Chemical Research in Chinese Universities 2004年第4期20卷 470-477页

作者： thomas Suhartanto Andrew p. E. York Malcolm L. H. Green Wolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of OxfordWolfson Catalysis Centre Inorganic Chemistry Laboratory University of Oxford South Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UKSouth Parks Road Oxford OX1 3QR UK

A series of tungsten promoted alumina supported nickel catalysts has been prepared for the carbon dioxide reforming of methane to synthesis gas. The catalysts have been characterized by means of XRD, TEM, and Laser Raman spectroscopy. It is shown that the addition of tungsten to the nickel catalyst can stabilize the catalyst and increase the resistance to carbon deposition. Adding a suitable amount of tungsten can also increase the catalyst activity to be close to that of supported noble metal catalysts. The carburisation of the tungsten modified nickel catalyst decreases the catalyst activity at lower reaction temperatures(performance at higher reaction temperatures. The alumina supported nickel catalyst modified by 0.67%(mass fraction) WO_3 has the equivalent equilibrium constant of the dry reforming reaction to that of alumina supported 5%(mass fraction) Ru at 873 K, and also has a lower activation energy for dry reforming than the latter.

关键词： Nickel catalyst Tungsten modifier CO_2 reforming Methane Syngas

Sensitivity of digital elevation models:The scenario from two tropical mountain river basins of the Western Ghats,India

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Geoscience Frontiers 2014年第6期5卷 893-909页

作者： Jobin thomas Sabu Joseph K.p.Thrivikramji K.S.Arunkumar Inter University Centre for Geospatial Information Science and Technology University of KeralaThiruvananthapuramKeralaIndia Department of Environmental Sciences University of KeralaThiruvananthapuramKeralaIndia Department of Geology University of KeralaThiruvananthapuramKeralaIndia Department of Geology MES CollegePonnaniMalappuramKeralaIndia

The paper evaluates sensitivity of various spaceborne digital elevation models （DEMs）, viz., Advanced Spaceborne Thermal Emission and Reflection Radiometer （ASTER）, Shuttle Radar Topography Mapping Mission （SRTM） and Global Multi-resolution Terrain Elevation Data 2010 （GMTED）, in comparison with the DEM （TOpO） derived from contour data of 20 m interval of Survey of India topographic sheets of 1 ： 50,000 scale. Several topographic attributes, such as elevation （above mean sea level）, relative relief, slope, aspect, curvature, slope-length and -steepness （LS） factor, terrain ruggedness index （TRI）, topo- graphic wetness index （TWI）, hypsometric integral （lhyp） and drainage network attributes （stream number and stream length） of two tropical mountain river basins, viz. Muthirapuzha River Basin and pambar River Basin are compared to evaluate the variations. Though the basins are comparable in extent, they differ in respect of terrain characteristics and climate. The result.,; suggest that ASTER and SRTM provide equally reliable representation of topography portrayed by TOp（） and the topographic attributes extracted from the spaceborne DEMs are in agreement with those derived from TOpO. Despite the coarser resolution, SRTM shows relatively higher vertical accuracy （RMSE -- 23 and 20 m respectively in MRB and pRB） compared to ASTER （RMSE - 33 and 24 m） and GMTED （RMSE - 59 and 48 m）. Vertical accuracy of all the spaceborne DEMs is influenced by relief of the terrain as well as type of vegetation. Further, GMTED shows significant deviation for most of the attributes, indicating its inability for mountain-river-basin-scale studies.

关键词： DEM ASTER SRTM GMTEDTropical mountain river basins Western Ghats

Temperature and mass scaling affect cutaneous and pulmonary respiratory performance in a diving frog

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Integrative Zoology 2021年第5期16卷 712-728页

作者： Ryan B.MCWHINNIE Jason p.SCKRABULIS thomas R.RAFFEL Department of Biological Sciences Oakland UniversityRochesterMichiganUSA

Global climate change is altering patterns of temperature variation,with unpredictable consequences for species and *** Metabolic Theory of Ecology(MTE)provides a powerful framework for predicting climate change impacts on ectotherm metabolic *** postulates that physiological and ecological processes are limited by organism metabolic rates,which scale predictably with body mass and *** purpose of this study was to determine if different metabolic proxies generate different empirical estimates of key MTE model parameters for the aquatic frog Xenopus laevis when allowed to exhibit normal diving *** used a novel methodological approach in combining a flow-through respirometry setup with the open-source Arduino platform to measure mass and temperature effects on 4 different proxies for whole-body metabolism(total O_(2) consumption,cutaneous O_(2) consumption,pulmonary O_(2) consumption,and ventilation frequency),following thermal acclimation to one of 3 temperatures(8℃,17℃,or 26℃).Different metabolic proxies generated different mass-scaling exponents(b)and activation energy(EA)estimates,highlighting the importance of metabolic proxy selection when parameterizing MTE-derived *** acclimated to 17℃ had higher O_(2) consumption across all temperatures,but thermal acclimation did not influence estimates of key MTE parameters EA and *** respiration generated lower MTE parameters than pulmonary respiration,consistent with temperature and mass constraints on dissolved oxygen availability,SA:V ratios,and diffusion distances across *** results show that the choice of metabolic proxy can have a big impact on empirical estimates for key MTE model parameters.

关键词： African clawed frog amphibian pneumotachography thermal biology

Weather or weathering?Growth of Nothofagus dombeyi on volcanic soils differing in nitrogen and phosphorus concentrations

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Journal of plant Ecology 2016年第5期9卷 596-607页

作者： Christoph Walter Cecilia A.pérez Frank M.thomas Faculty of Regional and Environmental Sciences GeobotanyUniversity of TrierBehringstraße 2154296 TrierGermany Departamento de Ecología de Ecosistemas Instituto de Ecología y Biodiversidad(IEB)Alameda 340SantiagoChile

Aims We tested whether—in addition to weather conditions—the concentrations of nitrogen and phosphorus in the substrate have an effect on the radial stem increment of Nothofagus dombeyi trees in old-growth forest stands on volcanic soil at the western slopes of the Andes in South-Central *** We took soil samples and tree increment cores from five proximate sites(1000-1300 m a.s.l.)that are located in the volcanic region of the Conguillío National park and differ in the age of the substrate(Miocene—3500 years B.p.)and in its concentrations of nitrogen(N)and phosphorus(p).The soil samples were also analysed on their concentrations of other plant mineral nutrients,carbon(C)and nitrogen isotope ratios(δ^(15)N).Tree-ring widths and the stem basal area increment(BAI)were related to climate *** selected tree rings,the stable isotope ratios of carbon(δ^(13)C)and oxygen(δ^(18)O)were determined and related to growth and climate *** FindingsConsistent with theory,the soils on the oldest substrate showed the highest(least negative)δ^(15)N values,but mineral N was the only nutrient whose concentration exhibited a straightforward(increasing)relationship with increasing substrate *** BAI was largest on the soil with the highest concentration of plant-available *** contrast to BAI,tree-ring chronologies did not differ among the study ***,tree-ring chronologies and BAI exhibited significantly positive correlations with summer precipitation,and negative correlations,with summer(December)temperature.A negative correlation was found betweenδ^(13)C and precipitation anomalies in the growing season(November-March).We interpret the negative correlations between growth and temperature,and betweenδ^(13)C andδ^(18)O in the tree rings,as an impairment of net carbon assimilation by anomalously warm weather conditions during the growing *** conclude that the growth of *** is mainly affected by high temperature and low precipitation

关键词： Andisol annual ring dendroecology temperate broadleaf forest weather anomalies

Iron-Catalysed C(sp^(2))-H Borylation with Expanded Functional Group Tolerance

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Chinese Journal of Chemistry 2022年第24期40卷 2875-2881页

作者： Luke Britton Jamie H.Docherty Gary S.Nichol Andrew p.Dominey Stephen p.thomas EaStCHEM School of Chemistry University of EdinburghEdinburghEH93FJ United Kingdom GSK Medicines Research Centre StevenageSG12NY United Kingdom

Arene C(sp^(2))-H bond borylation offers direct and efficient access to aryl boronic *** in situ catalyst activation and photoirradiation,the iron-catalysed C(sp^(2))-H borylation reaction of carboarenes,pyrroles,and indoles has been developed using only bench-stable pre-catalysts and *** functional group tolerance was observed including those not reported using previous methods(ArNH_(2),ArOH,ArSiR_(3),Arp(O)(O)_(2),ArC(O)NR_(2)).Mechanistic studies revealed iron-catalysed reductive deoxygenation,C—F protodefluorination,and a demethylation of aryl methyl ethers by C—O sigma bond hydroboration.

关键词： Iron Earth-abundant C-H borylation Boron photochemistry

Estimation of citrus canker lesion size using hyperspectral reflectance imaging

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International Journal of Agricultural and Biological Engineering 2013年第3期6卷 41-51页

作者： Nikhil p.Niphadkar thomas F.Burks Jianwei Qin Mark A.Ritenour ATW Automation Inc. DaytonOH 45402USA Department of Agricultural and Biological Engineering University of FloridaGainesvilleFL 32611USA U.S.Department of Agriculture BeltsvilleMD 20705USA Department of Horticultural Sciences University of FloridaGainesvilleFL 34945USA

The Citrus industry has need for effective approaches to remove fruit with canker before they are shipped to selective international market such as the European *** research aims to determine the detectable size limit for cankerous lesions using hyperspectral imaging *** developed multispectral algorithms using visible to near-infrared wavelengths,were used to segregate cankerous citrus fruits from other peel conditions(normal,greasy spot,insect damage,melanose,scab and wind scar).However,this previous work did not consider lesion size.A two-band ratio method with a simple threshold based classifier(ratio of reflectance at wavelengths 834 nm and 729 nm),which gave maximum overall classification accuracy of 95.7%,was selected for lesion size estimation in this *** smallest size of cankerous lesion detected in terms of equivalent diameter was 1.66 *** effect of variation of threshold values and number of erosion cycles(applying morphological erosion multiple times to the image)on estimation of smallest detectable lesion was *** was found that small threshold values gave better canker classification accuracies,while exhibiting a lower overall classification ***,higher threshold values portrayed the opposite *** threshold value of 1.275 gave the optimum tradeoff between canker classification accuracy,overall classification accuracy and minimal lesion size *** the number of erosion cycles reduced detection rates of smaller canker lesions,leading to the conclusion that a single erosion cycle gave the best size estimation *** erosion kernel of the size 3 mm×3 mm was used during the exploration.

关键词： citrus canker lesion size disease detection hyperspectral reflectance imaging image classification multispectral algorithm size detection limit

Using statistical learning to predict interactions between single metal atoms and modified MgO(100) supports

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npj Computational Materials 2020年第1期6卷 811-823页

作者： Chun-Yen Liu Shijia Zhang Daniel Martinez Meng Li thomas p.Senftle Department of Chemical and Biomolecular Engineering Rice UniversityHoustonTX 77005USA Department of Computer Science and Engineering School of Electrical Engineering and Computer SciencePennsylvania State UniversityUniversity ParkPA 16802USA Department of Statistics Rice UniversityHoustonTX 77005USA

Metal/oxide interactions mediated by charge transfer influence reactivity and stability in numerous heterogeneous *** this work,we use density functional theory(DFT)and statistical learning(SL)to derive models for predicting how the adsorption strength of metal atoms on MgO(100)surfaces can be enhanced by modifications of the ***(100)in its pristine form is relatively unreactive,and thus is ideal for examining ways in which its electronic interactions with metals can be enhanced,tuned,and controlled.

关键词： reactivity adsorption stability

A review on the best practices in concrete pavement design and materials in wet-freeze climates similar to Michigan

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第3期6卷 245-255页

作者： Naser p. Sharifi Siyu Chen Zhanping You thomas Van Dam Christopher Gilbertson Department of Civil and Environmental Engineering Michigan Technological University Houghton MI 49931 USA Nichols Consulting Engineers Chtd. Reno NV 89509 USA

The research presented in this paper aims to identify best practices of design and materials for concrete pavements in wet-freeze climates similar to the Michigan State. For the purposes of this paper, a best practice is a procedure that has been shown by field-validated research or experience to produce improved results and that is established or proposed as a standard suitable for widespread implementation. The local wet-freeze climate makes the requirements for Michigan's pavement system different from many other regions. Wetfreeze climates can result in various concrete pavement distress mechanisms such as thermally-induced cracking, freeze-thaw deterioration, accelerated cracking due to loss of support, frost heave, and material degradation. Therefore, appropriate procedures for design and material selection need to be selected to withstand high precipitation and freezing winter temperatures. Failure to take into account the climatic conditions may lead to inadequate or reduced pavement performance. However, utilizing appropriate techniques and materials could potentially improve the quality and increase the service life of the concrete pavement. Three design methods and five materials have been identified, and examples of their successful performance in wet-freeze climates are provided. In addition, the reasons that give them the superior performance in wet-freeze climates are discussed in detail.

关键词： Concrete pavements pavement design pavement materials Best practice Wet-freeze climate