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Gold Supported on Metal Oxides for Carbon Monoxide Oxidation

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Nano Research 2011年第2期4卷 180-193页

作者： Sonia A. C. Carabineiro Nina bogdanchikova Miguel Avalos-borja Alexey Pestryakov Pedro b. Tavares Jose L. Figueiredo Laboratário de Catálise e Materiais Associate Laboratory LSRE/LCM Departamento de Engenharia Química Faculdade de Engenharia Universidade do Porto 4200-465 Porto Portugal Universidad Nacional Autónoma de México Centro de Nanociencias y Nanotecnologia Carretera Tijuana-Ensenada 22800 Ensenada Baja California México Tomsk Polytechnic University 30 Lenin Avenue Tomsk 634050 Russia Universidade de Trás-os-Montes e Alto Douro Centro de Quimica-Vila Real Departamento de Química 5001-911 Vila Real Portugal

Au has been loaded （1% wt.） on different commercial oxide supports （CuO, La2O3, Y2O3, NiO） by three different methods： double impregnation （DIM）, liquid-phase reductive deposition （LPRD）, and ultrasonication （US）. Samples were characterised by N2 adsorption at -196℃, high-resolution transmission electron microscopy, selected area electron diffraction, energy dispersive X-ray spectrometry, high-angle annular dark-field imaging （Z-contrast）, X-ray diffraction, and temperature programmed reduction. CO oxidation was used as a test reaction to compare the catalytic activities. The best results were obtained with Au loaded by DIM on the NiO support, with an activity of 7.2 × 10^（-4） molco·gAu^（-1）·s^（-1） at room temperature. This is most likely related to the Au nanoparticle size being the smallest in this catalyst （average 4.8 nm）, since it is well known that gold particle size determines the catalytic activity. Other samples, having larger Au particle sizes （in the 2-12 nm range, with average sizes ranging from 4.8 to 6.8 nm）, showed lower activities. Nevertheless, all samples prepared by DIM had activities （from 1.1 × 10^（-4） to 7.2 × 10^（-4） molco·gAu^（-1）·S^（-1）, at room temperature） above those reported in the literature for gold on similar oxide supports. Therefore, this method gives better results than the most usual methods of deposition-precipitation or co-precipitation.

关键词： Gold heterogeneous catalysis oxidation electron diffraction X-ray diffraction

Ubiquitous Computing in the Library:Indiana State University Library's Experience

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现代图书情报技术 2002年第S1期 161-167页

作者： Ralph b.Gabbard judith Tribble Paul Asay Chris Hayes Indiana State University and Indiana University IndianaIndiana State UniversityIndianaIndiana State UniversityIndianaIndiana State UniversityIndiana

1 Introduction New technologies and other developments haye changedthe information seeking behaviors of the academic communityand the general *** is this more evident than inthe exponential growth of the World Wide Web and cellularphone *** to these user needs and newtechnologies,libraries are moving from being InformationWarehouses to becoming Information ***-text。

关键词：年刊连续出版物 Ubiquitous Computing in the Library 《现代图书情报技术》 Access PDA Card USb

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Unraveling molecular interactions in whey protein-kefiran composite films to understand their physicochemical and mechanical properties

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Food bioscience 2022年第6期50卷 345-354页

作者： Nina Gagliarini Cecilia b.Figoli judith Piermaria Alejandra bosch Analía G.Abraham Centro de Investigación y Desarrollo en Criotecnología de Alimentos- CIDCA (CCT-CONICET La Plata UNLPCIC-PBA)47 y 1161900La PlataArgentina Laboratorio de bioespectroscopía CINDEFI (CCT-CONICET La PlataUNLPCIC-PBA)50 y 1151900La PlataArgentina Área bioquímica y Control de Alimentos Facultad de Ciencias ExactasUNLP47 y 1151900La PlataArgentina

To enhance health promoting properties of edible whey protein films,the inclusion of kefiran to develop composite films was *** and mechanical properties of films prepared with different wpi:kefiran ratios,different percentage of plasticizer and subjected or not to a heat treatment were *** inter-and intra-molecular interactions produced by the incorporation of kefiran into whey-protein films were studied to understand the effect exerted by kefiran on the protein network that may affect the properties of the ***-scanning-calorimetry and Fourier-transform–infrared-spectroscopy studies revealed that kefiran does not affect proteins denaturation,but rather modifies protein-protein interactions in the films,exhibiting a change in wpi secondary structure and a drop in films'melting *** wpi:kefiran films had higher opacity,lower water content and lower water activity compared to single wpi *** of kefiran into the films decreases tensile strength and elastic modulus and produces an increment in the elongation at break *** was confirmed that the addition of a whey-protein denaturation step produces an improvement in the protein network that is crucial for the mechanical behavior of the *** the molecular interactions within composite films greatly aids in obtaining novel formulations with tailor-made physicochemical properties.

关键词： Edible films Kefiran Whey-proteins Interactions biomaterials

Ferroelectricity Induced by Oxygen Vacancies in Rhombohedral ZrO_(2) Thin Films

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Energy & Environmental Materials 2024年第1期7卷 229-237页

作者： Veniero Lenzi José P.b.Silva břetislav Šmíd Vladimir Matoín Cosmin M.Istrate Corneliu Ghica judith L.MacManus-Driscoll Luís Marques Physics Center of Minho and Porto Universities(CF-UM-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal Laboratory of Physics for Materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic National Institute of Materials Physics 105 bis Atomistilor 077125Magurele Romania Department of Materials Science and Metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhombohedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achieving robust ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhombic ***,a large spontaneous polarization observed in rhombohedral films is not fully understood,and there are also large discrepancies between experimental and theoretical *** this work,in rhombohedral ZrO_(2)thin films,we show that oxygen vacancies are not only a key factor for stabilizing the phase,but they are also a source of ferroelectric polarization in the *** is shown experimentally through the investigation of the structural properties,chemical composition and the ferroelectric properties of the films before and after an annealing at moderate temperature(400℃)in an oxygen environment to reduce the V_(o)concentration *** experimental work is supported by density functional theory(DFT)calculations which show that the rhombohedral phase is the most stable one in highly oxygen defective ZrO_(2)*** DFT calculations also show that V_(o)contribute to the ferroelectric *** findings reveal the importance of V_(o)for stabilizing rhombohedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhombohedral phase stability zirconia

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Single droplet drying of detergents:Experimentation and modelling

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Particuology 2021年第5期19卷 35-47页

作者： borja Hernandez Rosa Mondragon Mark A.Pintoa Leonor Hernandez J.Enrique Julia Juan Carlos Jarque Sergio Chiva Mariano Martin Newcastle Innovation Centre Procter&Gamble R&DNewcastle upon TyneUK Departamento de Ingenieria Quimica y Textil.Universidad de Salamanca SalamancaSpain Departamento de Ingenieria Mecanica y Construccion Universitat Jaume ICastellon de la PlanaSpain Instituto de Tecnologia Ceramica Universitat Jaume ICastellon de la PlanaSpain

This study evaluates the single droplet drying(SDD)of *** data are used to validate a theoretical multistage *** experiments are carried out in an acoustic levitator analysing six different detergent formulations at 393 *** work is completed by developing a model based on conservation *** model is composed of the three stages observed in the drying *** the first stage,an external surface drying stage occurs until the surface is saturated and the crust is *** the next stage,the drying rate is governed by diffusion through the *** the same time,the particle heats up until boiling conditions are achieved in the core of the *** this point,the third stage *** the final stage,the droplet core is in boiling conditions which are governed by the pressure drop through the crust and the concentration of *** model has been evaluated for the different formulations being flexible to predict the drying of different mixtures with good accuracy.

关键词： Drying Single droplet Acoustic levitator Detergents

Diabetes pathogenesis and management:the endothelium comes of age

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Journal of Molecular Cell biology 2021年第7期13卷 500-512页

作者： Kaitlin M.Love Eugene J.barrett Steven K.Malin Jane E.b.Reusch judith G.Regensteiner Zhenqi Liu Division of Endocrinology and Metabolism Department of MedicineUniversity of Virginia Health SystemCharlottesvilleVA 22908USA Department of Kinesiology and Health Rutgers UniversityNew BrunswickNJUSA Division of Endocrinology Metabolism and NutritionRutgers UniversityNew BrunswickNJUSA New Jersey Institute for Food Nutrition and HealthRutgers UniversityNew BrunswickNJUSA Institute of Translational Medicine and Research Rutgers UniversityNew BrunswickNJUSA Center for Women’s Health Research University of Colorado School of MedicineAuroraCOUSA Department of Medicine University of ColoradoAnschutz Medical CampusAuroraCOUSA Rocky Mountain Regional Veterans Affairs Medical Center AuroraCOUSA

Endothelium,acting as a barrier,protects tissues against factors that provoke insulin resistance and type 2 diabetes and itself responds to the insult of insulin resistance inducers with altered *** insulin resistance and vascular dysfunction occur early in the evolution of insulin resistance-related disease,can co-exist with and even contribute to the development of metabolic insulin resistance,and promote vascular complications in those *** impact of endothelial insulin resistance and vascular dysfunction varies depending on the blood vessel size and location,resulting in decreased arterial plasticity,increased atherosclerosis and vascular resistance,and decreased tissue *** with insulin resistance and diabetes are disproportionately impacted by cardiovascular disease,likely related to differential sex-hormone endothelium ***,reducing endothelial insulin resistance and improving endothelial function in the conduit arteries may reduce atherosclerotic complications,in the resistance arteries lead to better blood pressure control,and in the microvasculature lead to less microvascular complications and more effective tissue *** diabetes therapeutic modalities,including medications and exercise training,improve endothelial insulin action and vascular *** action may delay the onset of type 2 diabetes and/or its complications,making the vascular endothelium an attractive therapeutic target for type 2 diabetes and potentially type 1 diabetes.

关键词： diabetes insulin resistance endothelium vascular function

Large ferro-pyro-phototronic effect in 0.5ba(Zr_(0.2)Ti_(0.8))O_(3)-0.5(ba_(0.7)Ca_(0.3))TiO_(3)thin films integrated on silicon for photodetection

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Carbon Energy 2023年第6期5卷 1-10页

作者： JoséP.b.Silva Katarzyna Gwozdz Luís S.Marques Mario Pereira Maria J.M.Gomes judith L.MacManus‐Driscoll Robert L.Z.Hoye Centre of Physics of Universities of Minho and Porto(CF‐UM‐UP) University of MinhoBragaPortugal Laboratory of Physics for Materials and Emergent Technologies LapMETUniversity of MinhoBragaPortugal Department of Quantum Technologies Faculty of Fundamental Problems of TechnologyWroclaw University of Science and TechnologyWroclawPoland Department of Materials Science and Metallurgy CambridgeUK Inorganic Chemistry Laboratory Department of ChemistryUniversity of OxfordOxfordUK Department of Materials Imperial College LondonLondonUK

Coupling together the ferroelectric,pyroelectric,and photovoltaic characteristics within a single material is a novel way to improve the performance of *** this work,we take advantage of the triple multifunctionality shown by 0.5ba(Zr_(0.2)Ti_(0.8))O_(3)-0.5(ba_(0.7)Ca_(0.3))TiO_(3)(bCZT),as demonstrated in an Al/Si/SiOx/bCZT/ITO thin-film *** Si/SiOx acts as an n-type layer to form a metal-ferroelectric-insulator-semiconductor heterostructure with the bCZT,and with Al and ITO as *** photo-response of the device,with excitation from a violet laser(405 nm wavelength),is carefully investigated,and it is shown that the photodetector performance is invariant with the chopper frequency owing to the pyro-phototronic effect,which corresponds to the coupling together of the pyroelectric and photovoltaic ***,the photodetector performance was significantly better than that of the devices operating based only on the pyro-phototronic effect by a factor of 4,due to the presence of ferroelectricity in the ***,after a poling voltage of−15 V,for a laser power density of 230mW/cm^(2)and at a chopper frequency of 400Hz,optimized responsivity,detectivity,and sensitivity values of 13.1mA/W,1.7×10^(10)Jones,and 26.9,respectively,are ***,ultrafast rise and fall times of 2.4 and 1.5μs,respectively,are obtained,which are 35,000 and 36,000 times faster rise and fall responses,respectively,than previous reports of devices with the ferro-pyro-phototronic *** is understood based on the much faster ferroelectric switching in ferroelectric thin films owing to the predominant 180°domains in a single direction out of plane.

关键词： ferroelectric ferro-pyro-phototronic effect photodetector polarization-controlled response

Phylogenetic relationships of native and introduced bemisia tabaci (Homoptera:Aleyrodidae) from China and India based on mtCOI DNA sequencing and host plant comparisons

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Progress in Natural Science:Materials International 2007年第6期17卷 645-654页

作者： Susan A.Coats Ali M.Idris judith K.brown Department of Plant Sciences The University of ArizonaTucsonAZ 85721USA

Phylogenetic relationships for bemisia tabaci were reconstructed by analysis of a ～780 bp fragment of the mitochondrial cytochrome oxidase I (mtCOI) gene with an emphasis on geographic range and distribution among eight eudicot plant families that are common hosts of b. tabaci worldwide to elucidate key phylogeographic linkages between populations extant in China (n=31) and India (n=34). bootstrap values for the Maximum Parsimony tree were highly robust for all major nodes involving the major Asian clade, subgroups, and sister groups within, at 92%—100%. between-clade distances for the Southeast Asia and three other major clades, e.g. from sub-Sahara Africa, North Africa-Mediterranean, and the Americas, were approximately >16% divergent. Two major Asian subgroups (I, II) were resolved, which represented populations indigenous to the region, comprising two (I a, I b) and five (II a—e) sister groups, respectively, which diverged by 11%. Two distinct populations from sunflower in Hyderabad grouped separately within the two Asian subgroups. All other populations grouped uniquely within Asian subgroup II or I. The "b" biotype was identified in 23 collections from China at 97.3%—99.5% nucleotide identity with "b" biotype reference sequences; it was not identified in collections from India. The majority of haplotypes were associated with 3—4 plant families, with one exception that for sister group IId (sesame, India), it might be monophagous. Thus, b. tabaci from the southeastern and near eastern regions of the Asian continent comprise of a large number of ancestral, richly divergent, mostly polyphagous populations. This region is therefore hypothesized to constitute an important Old World center of diversification for the b. tabaci complex, together with sub-Saharan Africa.

关键词： bemisia tabaci complex cytochrome oxidase I host range phylogenetic relationship

Wind Power Uncertainty and Power System Performance

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Engineering（科研） 2013年第10期5卷 41-51页

作者： C. Lindsay Anderson judith b. Cardell Departmentof biological and Environmental Engineering Cornell University Ithaca USA Picker Engineering Program and Department of Computer Science Smith College Northampton USA

The penetration of wind power into global electric power systems is steadily increasing, with the possibility of 30% to 80% of electrical energy coming from wind within the coming decades. At penetrations below 10% of electricity from wind, the impact of this variable resource on power system operations is manageable with historical operating strategies. As this penetration increases, new methods for operating the power system and electricity markets need to be developed. As part of this process, the expected impact of increased wind penetration needs to be better understood and quantified. This paper presents a comprehensive modeling framework, combining optimal power flow with Monte Carlo simulations used to quantify the impact of high levels of wind power generation in the power system. The impact on power system performance is analyzed in terms of generator dispatch patterns, electricity price and its standard deviation, CO2 emissions and amount of wind power spilled. Simulations with 10%, 20% and 30% wind penetration are analyzed for the IEEE 39 bus test system, with input data representing the New England region. Results show that wind power predominantly displaces natural gas fired generation across all scenarios. The inclusion of increasing amounts of wind can result in price spike events, as the system is required to dispatch down expensive demand in order to maintain the energy balance. These events are shown to be mitigated by the inclusion of demand response resources. benefits include significant reductions in CO2 emissions, up to 75% reductions at 30% wind penetration, as compared to emissions with no wind integration.

关键词： Wind Power Power System Operations Variable Energy Resources Demand Response