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11.
In this study, the gel strength and visible microstructure of fat containing β-lactoglobulin-κ-carrageenan gels were investigated using puncture testing and confocal scanning laser microscopy, respectively. The gel strength was closely linked to the visible microstructure of the whey protein network as stained with Rhodamine B. Covalent labelling of κ-carrageenan with FITC prior to gel formation enabled localisation of the hydrocolloid phase, but caused a significant drop in the gel strength. This effect coincided with the observed reduction of the κ-carrageenan intrinsic viscosity, which was found to be a result of the labelling process. The use of a novel dye, V03-01136, for the staining of fat allowed for the specific and concurrent visualisation of the protein, hydrocolloid and fat phases under the conditions applied in the study. 相似文献
12.
Akif Soltan Matthew S. Dargusch Zhiming Shi Darren Gerrard Sulaiman Al Shabibi Yu-Chieh Kuo Andrej Atrens 《工业材料与腐蚀》2020,71(6):956-979
This study studied corrosion in 0.1 M Na2SO4, 0.1 M NaCl, and 0.6 M NaCl, all saturated with Mg(OH)2, using weight loss, hydrogen evolution, and electrochemical measurements. Corrosion was similar in all cases. Nevertheless, the corrosion rates were alloy-dependent, were somewhat lower in 0.1 M Na2SO4 than in 0.1 M NaCl, and increased with NaCl concentration. The corrosion damage morphology was similar for all solutions; the extent correlated with the corrosion rate. The corrosion rates evaluated by the electrochemical methods were lower than those evaluated from hydrogen evolution, consistent with the Mg corrosion mechanism involving the unipositive Mg+ ion. 相似文献
13.
A high abundance of methane and its relatively low price make it an attractive raw feedstock for the production of ethylene, which is in the consumer demand in recent years. Direct catalytic nonoxidative conversion is interesting, because it could be utilized on natural gas well sites. Monometallic and bimetallic Fe and Mo catalysts were prepared for the purpose of the coupling to ethane and ethene. Three supported materials were synthesized with the following loading of metal: 2.5‐wt% Fe, 5.0‐wt% Fe, and 2.5‐wt% Mo on HZSM‐5. Process' chemical reactions were also catalyzed with a constant 2.5‐wt% Mo/HZSM‐5, which had different amounts of Fe, namely, 0.5, 1.0, and 2.5 wt%. Fourier transform infrared (FTIR), N2 adsorption/desorption, NH3 temperature‐programmed desorption (TPD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X‐ray diffraction (XRD) were applied for characterization. Coke, accumulated on spent solids, was determined by thermogravimetric analysis (TGA). Activity was evaluated in quartz‐packed bed reactor. All surfaces suffered from deactivation due to carbon formation. The addition of Fe to Mo increased CH4 reacted. The highest selectivity for alkenes was achieved over 1.0‐wt% Fe to 2.5‐wt% Mo/HZSM‐5. At the peak of performance, the C‐based reactivity was 52% for olefins and 2% for alkanes. Stability was accomplished over 2.5‐wt% Fe/HZSM‐5, where the rate of C2 synthesis was comparatively stable for 20 hours of the time on stream. The selective C‐basis yield for C2H4 and C2H6 was 36% and 23%, respectively. The lowest measured quantity of (carbonaceous) by‐products was deposited on 2.5‐wt% Fe/HZSM‐5 after 26 hours. Propylene was detected very limitedly. 相似文献
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15.
Andrej Paul Bertram Schwind Christian Weinberger Michael Tiemann Thorsten Wagner 《Advanced functional materials》2019,29(43)
A nanocomposite material based on copper(II) oxide (CuO) and its utilization as a highly selective and stable gas‐responsive electrical switch for hydrogen sulphide (H2S) detection is presented. The material can be applied as a sensitive layer for H2S monitoring, e.g., in biogas gas plants. CuO nanoparticles are embedded in a rigid, nanoporous silica (SiO2) matrix to form an electrical percolating network of low conducting CuO and, upon exposure to H2S, highly conducting copper(II) sulphide (CuS) particles. By steric hindrance due to the silica pore walls, the structure of the network is maintained even though the reversible reaction of CuO to CuS is accompanied by significant volume expansion. The conducting state of the percolating network can be controlled by a variety of parameters, such as temperature, electrode layout, and network topology of the porous silica matrix. The latter means that this new type of sensing material has a structure‐encoded detection limit for H2S, which offers new application opportunities. The fabrication process of the mesoporous CuO@SiO2 composite as well as the sensor design and characteristics are described in detail. In addition, theoretical modeling of the percolation effect by Monte‐Carlo simulations yields deeper insight into the underlying percolation mechanism and the observed response characteristics. 相似文献
16.
Monica Popa Jose Maria Calderon Moreno Cora Vasilescu Silviu Iulian Drob Elena Ionela Neacsu Andrej Coer Julija Hmeljak Gregor Zerjav Ingrid Milošev 《Metallurgical and Materials Transactions A》2014,45(7):3130-3143
This article analyses the microstructure, electrochemical behavior, and biocompatibility of a novel Ti-20Nb-10Zr-5Ta alloy with low Young’s modulus (59 GPa) much closer to that of bone, between 10 and 30 GPa, than Ti and other Ti alloys used as implant biomaterial. XRD and SEM measurements revealed a near β crystalline microstructure containing β phase matrix and secondary α phase, with a typical grain size of around 200 μm. The corrosion behavior in neutral Ringer solution evidenced: self-passivation behavior characterizing a very resistant passive film; an easy passivation as a result of favorable influence of the alloying elements Nb, Zr, and Ta that participate with their passive oxides to the formation of the alloy passive film; low corrosion and ion release rates corresponding with very low toxicity. In MEM solution, the novel alloy demonstrated very high corrosion resistance and no susceptibility to localized corrosion. Biocompatibility was evaluated on in vitro human osteoblast-like and human immortalized pulmonary fibroblast cell (Wi-38) lines and the new Ti-20Nb-10Zr-5Ta alloy exhibited no cytotoxicity. The new Ti-20Nb-10Zr5Ta alloy is a promising material for implants due to combined properties of low elastic modulus, very low corrosion rate, and good biocompatibility. 相似文献
17.
Natasa Vujica Herzog Stefano Tonchia Andrej Polajnar 《Computers & Industrial Engineering》2009,57(3):963-975
An empirical analysis is presented for researching linkages between manufacturing strategy, benchmarking, performance measurement (PM) and business process reengineering (BPR). Although the importance of these linkages has been described in conceptual literature, it has not been widely demonstrated empirically. The survey research was carried out in 73 medium and large-sized Slovenian manufacturing companies within the mechanical, electro-mechanical and electronic industries. The resulting data were subjected to reliability and validity analyses. Canonical correlation analysis was used to test six hypotheses.The results confirmed the need for a strategically-driven BPR approach and the positive impact of performance measurement on BPR performance. 相似文献
18.
Arturas Kaklauskas Andrej Vlasenko Vidas Raudonis Edmundas Kazimieras Zavadskas Renaldas Gudauskas Mark Seniut Algirdas Juozapaitis Ieva Jackute Loreta Kanapeckiene Silva Rimkuviene Gabrielius Kaklauskas 《Engineering Applications of Artificial Intelligence》2013,26(1):35-50
Students and lecturers would like to know how well students have learned the study materials being taught. A formal test or exam would cause needless stress for students. To resolve this problem, the authors of this article have developed an Intelligent Pupil Analysis (IPA) System. A sufficient amount of studies worldwide prove an interrelation between pupil size and a person's cognitive load. The obtained research results are comparable with the results from other similar studies. The original contribution of this article, compared to the research results published earlier, is as follows: the IPA System developed by the authors is superior to the traditional pupil analysis research due to the integration of pupil analysis with subsystems of decision support, recommender and intelligent tutoring systems and innovative Models of the Model-base, which permit a more detailed analysis of the knowledge attained by a student. This article ends with a case study to demonstrate the practical operation of the IPA System. 相似文献
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20.
Characterising heave,pitch, and roll motion of road vehicles with principal component and frequency analysis 下载免费PDF全文
Michael Thomas Long Vincent Rouillard Matthew James Lamb Michael Andrej Sek 《Packaging Technology and Science》2018,31(1):3-13
For the great majority of transport vehicles, the magnitude of the heave vibration is generally more severe than pitch and roll. Consequently, the measurement, analysis, and simulation of the vehicle vibrations have been focused on vertical vibration. Despite this, it is now being increasingly recognised that the combination of heave, pitch, and roll vibratory motion can induce more severe damage to shipments than vertical vibration alone. Although the pitch and roll motion of road vehicles can now be readily measured, there is little information on how to analyse the data to produce meaningful statistical relationships between the three variables. This paper builds upon previous work that showed that there is some correlation between pitch, roll, and heave motion and that these relationships are dependent on vehicle geometry, including payload mass, centre of mass, vehicle roll centre, and moments of inertia as well as vehicle speed and the road surface. In this paper, data from a range of quasi‐controlled experiments, which involved driving vehicles at constant‐speed on selected roads, were analysed using principal component analysis as well as frequency domain analysis to reveal the relationship between heave, pitch, and roll motion. This was undertaken for a variety of vehicle speeds and routes in order to establish if they influence pitch and roll response. Results are presented in the form of distribution functions, statistical coefficients, and frequency response functions, all of which are useful for helping to define parameters for the simulation of complete, three‐axis vibrations using multi‐axis vibration test systems. 相似文献