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51.
Cover Picture: DNA Antenna Tile‐Associated Deoxyribozyme Sensor with Improved Sensitivity (ChemBioChem 21/2016) 下载免费PDF全文
52.
Studying of cellular interaction of hairpin‐like peptide EcAMP1 from barnyard grass (Echinochloa crusgalli L.) seeds with plant pathogenic fungus Fusarium solani using microscopy techniques 下载免费PDF全文
53.
Enhanced transport properties of Sn-substituted proton-conducting BaZr0.8Sc0.2O3–δ ceramic materials
Inna A. Zvonareva Anna V. Kasyanova Artem P. Tarutin Gennady K. Vdovin Julia G. Lyagaeva Dmitry A. Medvedev 《Journal of the American Ceramic Society》2022,105(3):2105-2115
High-temperature proton conductors based on acceptor-doped barium zirconate exhibit excellent chemical stability in atmospheres containing CO2 or H2O. However, due to their refractory nature, these conductors have a low grain growth rate, which negatively affects the overall electrical conductivity. A possible strategy for increasing the ionic conductivity of zirconates lies in the partial substitution of Zr-ions with other isovalent dopants. In this work, we carried out systematic studies of the crystal structure, microstructure, hydration capacity, transport, and thermal properties of BaZr0.8–xSnxSc0.2O3–δ (x = 0, 0.1, and 0.2). According to X-ray powder diffraction and scanning electron microscopy data, all studied ceramic samples have a cubic perovskite structure, whose average grain size decreases with tin doping. It is found that the composition with x = 0.1 exhibits the highest values in terms of total, ionic, grain, and grain-boundary conductivities. The complex analysis of the obtained data shows that a low-level substitution of Zr4+- with Sn4+-ions is a competent approach for designing new proton-conducting electrolytes attractive for high-temperature applications. 相似文献
54.
Kinetic modeling of hemicellulose hydrolysis in the presence of homogeneous and heterogeneous catalysts 下载免费PDF全文
Tapio Salmi Dmitry Yu. Murzin Päivi Mäki‐Arvela Bright Kusema Bjarne Holmbom Stefan Willför Johan Wärnå 《American Institute of Chemical Engineers》2014,60(3):1066-1077
Kinetic models were developed for the hydrolysis of O‐acetyl‐galactoglucomannan (GGM), a hemicellulose appearing in coniferous trees. Homogeneous and heterogeneous acid catalysts hydrolyze GGM at about 90°C to the monomeric sugars galactose, glucose, and mannose. In the presence of homogeneous catalysts, such as HCl, H2SO4, oxalic acid, and trifluoroacetic acid, the hydrolysis process shows a regular kinetic behavior, while a prominent autocatalytic effect was observed in the presence of heterogeneous cation‐exchange catalysts, Amberlyst 15 and Smopex 101. The kinetic models proposed were based on the reactivities of the nonhydrolyzed sugar units and the increase of the rate constant (for heterogeneous catalysts) as the reaction progresses and the degree of polymerization decreases. General kinetic models were derived and special cases of them were considered in detail, by deriving analytical solutions for product distributions. The kinetic parameters, describing the autocatalytic effect were determined by nonlinear regression analysis. The kinetic model described very well the overall kinetics, as well as the product distribution in the hydrolysis of water soluble GGM by homogeneous and heterogeneous catalysts. The modelling principles developed in the work can be in principle applied to hydrolysis of similar hemicelluloses as well as starch and cellulose. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1066–1077, 2014 相似文献
55.
Päivi Mäki-Arvela Mika Mikkola Jarl Hemming Kari Eränen Stefan Willför Dmitry Yu. Murzin 《Journal of the American Oil Chemists' Society》2014,91(6):1035-1046
Mixtures of fatty acids and rosin acids are industrially important products utilized as a raw material for several purposes. Their thermal properties, especially cold stability and crystallization behavior is also important. Several fatty acid and rosin acid mixtures both from industrial products and from commercially available fatty and rosin acids were prepared and treated for 30 min at 80 °C under an inert atmosphere. Thereafter, the mixture was cooled to the desired temperature. Determination of the cloud point, chemical analysis of liquid and solid phase, thermal analysis by differential scanning calorimetry as well as morphology analysis by scanning electron microscopy were performed. The results revealed that crystallization was more rapid when it occurred at 10 °C compared to 25 °C. The crystal sizes increased with decreasing the crystallization temperature. Furthermore, crystals were of irregular shape and agglomerated when rapid cooling of the mixture occurred. Chemical analysis revealed that liquid phase was enriched with stearic acid, whereas crystals contained large amounts of abietic, dehydroabietic and linoleic acids. The cloud point of the mixtures increased with increasing amount of stearic and rosin acids. Dehydroabietic acid addition improved the cold stability of the synthetic fatty acid–rosin acids mixture. 相似文献
56.
Alena Sergeeva Natalia Feoktistova Vladimir Prokopovic Dmitry Gorin Dmitry Volodkin 《Advanced Materials Interfaces》2015,2(18)
Fabrication of porous alginate hydrogels with a well‐controlled architecture useful for tissue engineering is still a challenge. Here, CaCO3‐based templating is utilized to design stable alginate gels with controlled pore dimensions in the range of 5–50 μm. The mechanism of pore formation is studied considering two factors affecting the pore size: i) osmotic pressure generated during the dissolution of sacrificial CaCO3 templates and ii) alginate gel network density. Osmotic pressure can achieve an upper limit of 100 MPa but does not affect the gel porosity. Additional osmotic pressure (range of kPa) induced by dextrans pre‐encapsulated into CaCO3 vaterite is also insufficient for pore enlargement. Pore stability depends merely on the gel network density and on the number of crosslinking calcium ions provided locally per unit time; pores are collapsed when template dissolution is too slow or if there is insufficient alginate concentration (below 2%). Young's modulus indicates the soft nature of the prepared hydrogels (tens of kPa) applicable as soft porous scaffolds with a tuned internal structure. 相似文献
57.
Anna Fensel Slobodanka Tomic Vikash Kumar Milan Stefanovic Sergey V. Aleshin Dmitry O. Novikov 《Informatik-Spektrum》2013,36(1):46-57
As the urgent need for efficient and sustainable energy usage becomes ever more apparent, interest in Smart Homes is on the rise. The SESAME-S project (SEmantic SmArt Metering – Services for Energy Efficient Houses) uses semantically linked data to actively assist end-consumers in making well-informed decisions and controlling their energy consumption. By integrating smart metering and home automation functionality, SESAME-S works to effectively address the potential mass market of end-consumers with an easily customizable solution that can be widely implemented in domestic or business environments, with expected savings of over 20?% from the total energy bill. The developed system is a basis for conceptualizing, demonstrating, and evaluating a variety of innovative end-consumer services and their user interface paradigms. In this paper, we present the SESAME-S system as a whole and discuss the semantically enabled services, demonstrating that such systems may have broad acceptance in the future. The data obtained through such systems will be invaluable for future global energy-efficiency strategies and businesses. 相似文献
58.
59.
Tapio Salmi Henrik GrénmanJohan Wärnå Dmitry Yu. Murzin 《Chemical Engineering Research and Design》2013
Typical features of liquid–solid reactions were reviewed: reaction kinetics, mass transfer effects and particle morphology. It was concluded that classical liquid–solid models based on ideal, non-porous geometries (sphere, infinite cylinder, slab) cannot satisfactorily describe real reactive solid particles with various surface defects, such as cracks, craters and limited porosity. Typically a too low reaction order for the reactive solid is predicted by the classical models. The surface morphology can be revealed by electron microscopy, which gives inspiration to develop new mathematical models for reactive solids. 相似文献
60.
Ajay Kumar Shukla Ryabov Dmitry Olena Volkova Piotr R. Scheller Brahma Deo 《Metallurgical and Materials Transactions B》2011,42(1):224-235
The melting of steel scrap in high temperature liquid iron melt is investigated by conducting cold model experiments of the
melting of ice sample of different geometries and sizes in an argon-stirred vessel containing water. The melting process of
ice samples is observed using a high-speed camera. Design of experiments is based on similarity criteria. The relationships
between non-dimensional groups related to heat transfer (Nu, Re, Pr, and Gr) are derived for different experimental conditions.
The results are compared with those reported in the literature. The heat transfer coefficient is estimated as a function of
mixing power and is found to be in good agreement with the calculated values obtained by using reported relationships in literature. 相似文献