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81.
Comparative studies are provided for the properties of compacted and cast specimens of fine-grained ceramic concrete prepared
on the basis of a mixed HCBS and two varieties of refractory filler with different Al2O3content from bauxite and chamotte based on Arkalyk clay. For specimens containing a chamotte filler, after firing at above
1250°C there is typically significant linear growth (up to 2.5%), connected with secondary mullite formation and caused by
interphase reaction of SiO2 from filler grains and very fine Al2O3 of the matrix system. The correlation of matrix system properties and materials with a refractory filler is analyzed 相似文献
82.
This paper considers a generalized framework to study OSNR optimization-based end-to-end link level power control problems in optical networks. We combine favorable features of game-theoretical approach and central cost approach to allow different service groups within the network. We develop solutions concepts for both cases of empty and nonempty feasible sets. In addition, we derive and prove the convergence of a distributed iterative algorithm for different classes of users. In the end, we use numerical examples to illustrate the novel framework. 相似文献
83.
Tomáš Horák Jiří Čulík Vladimír Kellner Marie Jurková Pavel Čejka 《Journal of the Institute of Brewing》2009,115(3):214-219
Dominant trends in analytical chemistry include miniaturization in sample preparation techniques and faster run times to provide high‐throughput screening, fast process monitoring and fast method development. This study focused on the application of narrow bore gas chromatographic capillary columns, 0.18 mm internal diameter, for brewing analyses. On these capillary columns, faster analyses could be performed compared to conventional GC capillary columns using 0.32 to 0.53 mm internal diameters. The robustness of the state‐of‐the‐art faster capillary gas chromatography, without compromising resolution, has been demonstrated with the analyses of beer flavour compounds such as lower and higher alcohols, esters and other volatile compounds such as acetaldehyde and dimethyl sulphide in beer. These methods were able to reduce sample run times by 60%. 相似文献
84.
Mladen Brnčić Tomislav Bosiljkov Marko Ukrainczyk Branko Tripalo Suzana Rimac Brnčić Sven Karlović Damir Karlović Damir Ježek Dražen Vikić Topić 《Food and Bioprocess Technology》2011,4(7):1296-1306
Production of extrudates from cereals is an often-used technological process in today’s world food industry. Extrudates from
corn flour produced using the twin-screw extrusion process and enriched with whey protein concentrate represent high-quality
source of proteins and fats. Whey protein concentrate (WPC) as a valuable source of proteins and minerals is one of the highest-quality
components for possible extrudate enrichment. In this paper, the influence of various WPC addition and some extrusion process
parameters such as feed moisture content (
Q\textH\text2 \textO Q_{{{\text{H}}_{\text{2}} {\text{O}}}} ) on physicochemical properties of directly expanded corn flour extrudates manufactured in twin-screw co-rotating extruder
was investigated. Whey protein concentrate was added in the following ratios 7.5%, 15% and 22.5% and water in 10.08, 12.18
and 14.28 L/h. Final composition of products is determined with measuring of protein, fat and water shares, water absorption
index (WAI) and water solubility index (WSI). With added WPC and with increase of water volume flow, there was a significant
rise in total protein, fat and water content in final products, as well as lowering of WSI and rising of WAI indexes. The
statistical analysis of the obtained data shows that the lowest WSI and the highest WAI had samples with the largest share
of WPC (22.5%) and water volume flow of 14.28 L/h. Colour is measured for each sample, and results were represented with hue
angle (H), chroma (C) and lightness (L) values. Process parameters, WPC and
Q\textH\text2 \textO Q_{{{\text{H}}_{\text{2}} {\text{O}}}} influence the increase of saturation of C and lightness of L colour value, while H value stays unchanged. Mean value of H
was 90.14 ± 1.06, which corresponds to dominance of yellow colour of samples. 相似文献
85.
Iva Blazkova Hoai Viet Nguyen Simona Dostalova Pavel Kopel Maja Stanisavljevic Marketa Vaculovicova Marie Stiborova Tomas Eckschlager Rene Kizek Vojtech Adam 《International journal of molecular sciences》2013,14(7):13391-13402
Magnetic particle mediated transport in combination with nanomaterial based drug carrier has a great potential for targeted cancer therapy. In this study, doxorubicin encapsulation into the apoferritin and its conjugation with magnetic particles was investigated by capillary electrophoresis with laser-induced fluorescence detection (CE-LIF). The quantification of encapsulated doxorubicin was performed by fluorescence spectroscopy and compared to CE-LIF. Moreover, the significant enhancement of the doxorubicin signal was observed by addition of methanol into the sample solution. 相似文献
86.
Roland Steim Tayebeh Ameri Pavel SchilinskyChristoph Waldauf Gilles DennlerMarkus Scharber Christoph J. Brabec 《Solar Energy Materials & Solar Cells》2011,95(12):3256-3261
Here we report on organic photovoltaic's (OPV) suitable for low light applications. In this paper, we illustrate the impact of Rs and Rp for indoor and outdoor applications. In addition, we propose a simple physics approach to predict the behavior of organic solar cells under various illumination intensities through electrical modeling. The combination of simulation and modeling allows to define a set of design rules for OPVs under low light illumination. The performance of various organic solar cells under low light intensity is compared with our predictions and excellent correlation is found. OPV shows high performance under low light conditions. 相似文献
87.
88.
Muha Abdullah Al Pavel Masud Abdullah Chowdhury 《The International journal of environmental studies》2013,70(3):261-269
This paper offers an economic evaluation of the floating garden as a means of adapting to climate change in Bangladesh. The study showed that the monthly income of some farmers using such gardens increased from US$12.02 to US$48.08. These folk farmers lacked alternative work especially during the monsoon period. The floating garden uses available natural resources, adjusts to wet conditions and helps the flood-prone people to earn a living, and can be an adaptive response to frequent disaster events in Bangladesh. 相似文献
89.
Pavel Ctibor Helene Ageorges Josef Sedlacek Radim Ctvrtlik 《Ceramics International》2010,36(7):2155-2162
Plasma spraying enables to create layers with thickness in a millimeter range adhering on various substrates. This paper provides a study of electric and mechanical properties of BaTiO3 coatings prepared by atmospheric plasma spraying. The spraying was carried out by a direct current gas-stabilized plasma gun. BaTiO3 was fed into the plasma jet as a feedstock powder prepared by a reactive sintering of micrometer-sized powders of BaCO3 and TiO2. Microstructure and phase composition are reported and discussed in connection with electric and mechanical properties. The ability of the used techniques to detect precisely the phase transformation temperatures of BaTiO3 plasma sprayed coatings is discussed as well. A depth-sensing indentation measurement was done between 290 and 520 K to provide local mechanical characterization. The elastic modulus has shown slightly higher values than that reported typically in papers focused on BaTiO3 ferroelectric thin films. The average Vickers microhardness is tested to characterize the samples in larger scale. A wear resistance in a slurry environment is reported as well. Dielectric properties are reported for the temperature window of existence of the tetragonal ferroelectric phase. Relative permittivity and loss factor are studied at frequency from 50 Hz to 1 MHz and temperature from 260 to 400 K. 相似文献
90.
A surface of epoxy-impregnated hardened cement paste was investigated using a novel atomic force microscopy (AFM) imaging mode that allows for the quantitative mapping of the local elastic modulus. The analyzed surface was previously prepared using focussed ion beam milling. The same surface was also characterized by electron microscopy and energy-dispersive X-ray spectroscopy.We demonstrate the capability of this quantitative nanomechanical mapping to provide information on the local distribution of the elastic modulus (from about 1 to about 100 GPa) with a spatial resolution in the range of decananometers, that corresponds to that of low-keV back-scattered electron imaging. Despite some surface roughness which affects the measured nanomechanical properties it is shown that topography, adhesion and Young's modulus can be clearly distinguished.The quantitative mapping of the local elastic modulus is able to discriminate between phases in the cement paste microstructure that cannot be distinguished from the corresponding back-scattered electron images. 相似文献