排序方式: 共有31条查询结果,搜索用时 15 毫秒
21.
Charalampos Vasilopoulos Eveline De Mey Lore Dewulf Hubert Paelinck Anny De Smedt Frank Vandendriessche Luc De Vuyst Frédéric Leroy 《Food microbiology》2010
Growth and metabolite production of three dominant bacterial isolates (Carnobacterium divergens 3M14, Leuconostoc carnosum 3M42, and Brochothrix thermosphacta RMS6) from modified-atmosphere-packaged (MAP), artisan-type cooked ham were assessed for their interactions in view of the development of a bioprotective culture. During monoculture experiments in cooked ham simulation medium, Leuc. carnosum 3M42 converted the available glucose into lactic acid and ethanol, whereas the two other strains produced additional metabolites such as acetic acid and 3-methyl-1-butanol. When grown in co-culture, Leuc. carnosum 3M42 suppressed the growth and metabolism of B. thermosphacta RMS6. In contrast, a co-culture of the latter bacterium with C. divergens 3M14 led to a variety of spoilage-related metabolic compounds. Subsequently, experiments with a commercial cooked ham product indicated that Leuc. carnosum 3M42 dominated the meat matrix and improved acceptability of the product over time, hence acting as a bioprotective culture for MAP, artisan-type cooked ham. 相似文献
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Algorithmic differentiation of an industrial airfoil design tool coupled with the adjoint CFD method
Banović Mladen Vasilopoulos Ilias Walther Andrea Meyer Marcus 《Optimization and Engineering》2020,21(3):1221-1242
Optimization and Engineering - Computer Aided Design (CAD) systems and tools are considered essential for industrial design. They construct and manipulate the geometry of a certain component with... 相似文献
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We demonstrate theoretically that quantum dots in bilayers of graphene can be realized. A position-dependent doping breaks the equivalence between the upper and lower layer and lifts the degeneracy of the positive and negative momentum states of the dot. Numerical results show the simultaneous presence of electron and hole confined states for certain doping profiles and a remarkable angular momentum dependence of the quantum dot spectrum, which is in sharp contrast with that for conventional semiconductor quantum dots. We predict that the optical spectrum will consist of a series of nonequidistant peaks. 相似文献
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Konstantinos Dimitriadis Konstantinos C. Vasilopoulos Tiverios C. Vaimakis Michael A. Karakassides Dilshat U. Tulyaganov Simeon Agathopoulos 《International Journal of Applied Ceramic Technology》2020,17(4):2025-2035
This study reports on the sintering behavior, crystallization process, and mechanical properties of novel glass-ceramics (CGs) produced by the glass powder compact consolidation method. Substitution of K2O for Na2O and MgO for CaO was attempted in the parent glasses belonging to Na2O-CaO-MgO-SiO2-P2O5-CaF2 system. Glass powder compacts were heat treated at various temperatures between 700°C and 900°C, taking under consideration the glass transition (Tg) and the crystallization peak (Tp) temperatures, which were experimentally determined for each investigated glass by thermal analysis (dilatometry and differential scanning calorimetry). The experimental results showed that sintering always preceded crystallization, regardless of the type of substitution. In the case of MgO substitution for CaO, crystallization was advanced in the range of 800°C-850°C, resulting in the formation of an assembly of crystalline phases, such as diopside, fluorapatite, and wollastonite. The substitution of K2O for Na2O increased the activation energy for crystallization, shifting crystallization process to a high temperature region, with the formation of alpha-potassium magnesium silicate, instead of wollastonite. The GCs produced had values of 22-31 GPa regarding the modulus of elasticity, 5.0-6.1 GPa concerning the microhardness, and 1.4-1.9 MPa⋅m0.5 as regard the fracture toughness, which are similar to those of the human jawbone. 相似文献
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Barbier M Vasilopoulos P Peeters FM 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2010,368(1932):5499-5524
We review the energy spectrum and transport properties of several types of one-dimensional superlattices (SLs) on single-layer and bilayer graphene. In single-layer graphene, for certain SL parameters an electron beam incident on an SL is highly collimated. On the other hand, there are extra Dirac points generated for other SL parameters. Using rectangular barriers allows us to find analytical expressions for the location of new Dirac points in the spectrum and for the renormalization of the electron velocities. The influence of these extra Dirac points on the conductivity is investigated. In the limit of δ-function barriers, the transmission T through and conductance G of a finite number of barriers as well as the energy spectra of SLs are periodic functions of the dimensionless strength P of the barriers, Pδ(x) = V(x)/?v(F), with v(F) the Fermi velocity. For a Kronig-Penney SL with alternating sign of the height of the barriers, the Dirac point becomes a Dirac line for P = π/2+nπ with n an integer. In bilayer graphene, with an appropriate bias applied to the barriers and wells, we show that several new types of SLs are produced and two of them are similar to type I and type II semiconductor SLs. Similar to single-layer graphene SLs, extra 'Dirac' points are found in bilayer graphene SLs. Non-ballistic transport is also considered. 相似文献
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Vasilopoulos Nicholas L.; Reilly Richard R.; Leaman Julia A. 《Canadian Metallurgical Quarterly》2000,85(1):50
Two studies were conducted to examine the effects of job familiarity and impression management on response latencies and scale scores for measures of personality and situational judgment. In a laboratory study using university students and a field study using U.S. Border Patrol Agent applicants, impression management was generally associated with faster personality item responses when job familiarity was high and with slower responses when job familiarity was low. Both impression management and job familiarity were associated with personality item responses that were more likely to lead to a job offer. The field study revealed a similar pattern of results for situational judgment scale response latencies, although only impression management was associated with item responses that were more likely to lead to a job offer. The implications for using response latencies to detect impression management on self-report measures are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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We present results for the resonant electronic transmission through graphene-based single and double barriers as a function of the incident wave vector, the widths and heights of the barriers, and the separation between them. Resonant features in the transmission result from resonant electron states in the wells or hole states in the barriers and strongly influence the ballistic conductance of the structures. 相似文献
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K.C. Vasilopoulos D.U. Tulyaganov S. Agathopoulos M.A. Karakassides J.M.F. Ferreira D. Tsipas 《Ceramics International》2009,35(2):555-558
Cr2O3-nucleated fine grained mono-mineral glass-ceramics of augite were produced from low-silica fly ash and additives of SiO2, Al2O3 and MgCO3, via two steps of heat treatment for nucleation and crystal growth. The starting glass approached the composition of CaMg0.75Al0.4Fe0.1Si1.75O6, derived from CaMg0.75Al0.5Si1.75O6, which belongs to diopside – Ca-Tschermak solid solutions. The influence of Cr2O3 (up to 0.75 wt.%) on the development of crystalline phases, the properties and the microstructure of the resultant glass-ceramics crystallized at different temperatures was investigated. 相似文献