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161.
This paper discusses the influence of mark-up of prices, costs due to damaged goods and advertising expenditure related to the ELS inventory model with discrete units. A numerical example is also given, with its detailed sensitivity analysis. 相似文献
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Ivan Ristić Ivan Krakovsky Teodora Janić Suzana Cakić Aleksandra Miletić Milovan Jotanović Tanja Radusin 《Journal of Thermal Analysis and Calorimetry》2018,132(2):895-905
Pure Fe3O4 and Mn-doped Fe3O4 nanoparticles were synthesized by simple wet chemical reduction technique using nontoxic precursors. Manganese doping of two concentrations, 10 and 15%, were employed. All the three synthesized nanoparticles were characterized by stoichiometry, crystal structure, and surface morphology. Thermal studies on as-synthesized nanoparticles of pure ferrite (Fe3O4) and manganese (Mn) doped ferrites were carried out. The thermal analysis of the three as-synthesized nanoparticles was done by thermogravimetric (TG), differential thermogravimetric, and differential thermal analysis techniques. All the thermal analyses were done in nitrogen atmosphere in the temperature range of 308–1233 K. All the thermocurves were recorded for three heating rates of 10, 15, and 20 K min?1. The TG curves showed three steps thermal decomposition for Fe3O4 and two steps thermal decompositions for Mn-doped Fe3O4 nanoparticles. The kinetic parameters of the three as-synthesized nanoparticles were evaluated from the thermocurves employing Kissinger–Akahira–Sunose (KAS) method. The thermocurves and evaluated kinetic parameters are discussed in this paper. 相似文献
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Several orientations of GaAs substrates, including (1 0 0), (4 1 1), (1 1 1) and (5 1 1) have been annealed in a metalorganic vapour phase epitaxy (MOVPE) horizontal reactor at different annealing temperatures and under different trimethyl-bismuth (TMBi) flux. Surface morphology of the annealed GaAs substrates was investigated by means of scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results show islands formation on all the studied samples. The density and size of Bi islands vary greatly with annealing temperature and TMBi flow. For different substrate orientations, the activation energies were deduced from Arrhenius plot of island density. Except for (5 1 1) oriented GaAs, all the studied orientations show the same activation energy of 1.8 eV. For low annealing temperature 420 °C, and under different Bi flux, each oriented substrate shows a specific behaviour. For higher temperatures 700 °C and above Bi islands are totally removed and the substrates are smooth. Surface change of (1 0 0) oriented GaAs substrate was in situ monitored by laser reflectometry. 相似文献
165.
Huidobro Pedro Alonso Pedro Janiš Vladimír Montes Susana 《Fuzzy Optimization and Decision Making》2022,21(4):553-580
Fuzzy Optimization and Decision Making - Convexity is a deeply studied concept since it is very useful in many fields of mathematics, like optimization. When we deal with imprecision, the convexity... 相似文献
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