optimal regime
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2021 ◽  
Vol 937 (2) ◽  
pp. 022098
Author(s):  
Mikhail Sergeev ◽  
Dmitry Yermolin ◽  
Galina Yermolina

Abstract The article presents research non-alcoholic carbonated tonic drink technology development from grape pomace. It was found that Ancellotta grape pomace extraction optimal regime is 60-65 °C at least 2 hours. Pomace volume fraction in the drink should be 3%, phenols mass concentration – 200 mg/l, anthocyanin allows to get a product with a soft pink color – 10 mg/l. Drink’s sugars mass concentration is 60 g/l, titrating acids – 3 g/l.


Author(s):  
Nelu CAZACU

The work is based on carbonitriding in a fluidized layer with methane and ammonia gas applied to 41Cr4 steel samples. To achieve the best possible results, other factors must be taken into account, than those specific to carbonitring. It was necessary to use a partially factorial working procedure due to the increase in the number of factors. An A18 matrix has been used, with 18 lines of experiments in which three levels have been modified for 6 factors. The objective function was fixed at the final hardness after carbonitriding, hardening and tempering. The carbonitriding was performed in fluidized bed with granular solid ground and sorted to 0.1- to 0.16mm, and brought to fluidization with a mixture of methane and ammonia. The hardening has been done directly after carbonitriding in the fluidized bed. The experiments have been performed according to Taguchi Methods and the results indicate an optimal regime and the influence of the factors considered on the hardness after the thermo-chemical treatment and the thermal treatment. Metallographic analysis has been performed on the carbonitrided layer.


Author(s):  
Johannes Alt ◽  
Raphael Ducatez ◽  
Antti Knowles

AbstractWe analyse the eigenvectors of the adjacency matrix of a critical Erdős–Rényi graph $${\mathbb {G}}(N,d/N)$$ G ( N , d / N ) , where d is of order $$\log N$$ log N . We show that its spectrum splits into two phases: a delocalized phase in the middle of the spectrum, where the eigenvectors are completely delocalized, and a semilocalized phase near the edges of the spectrum, where the eigenvectors are essentially localized on a small number of vertices. In the semilocalized phase the mass of an eigenvector is concentrated in a small number of disjoint balls centred around resonant vertices, in each of which it is a radial exponentially decaying function. The transition between the phases is sharp and is manifested in a discontinuity in the localization exponent $$\gamma (\varvec{\mathrm {w}})$$ γ ( w ) of an eigenvector $$\varvec{\mathrm {w}}$$ w , defined through $$\Vert \varvec{\mathrm {w}} \Vert _\infty / \Vert \varvec{\mathrm {w}} \Vert _2 = N^{-\gamma (\varvec{\mathrm {w}})}$$ ‖ w ‖ ∞ / ‖ w ‖ 2 = N - γ ( w ) . Our results remain valid throughout the optimal regime $$\sqrt{\log N} \ll d \leqslant O(\log N)$$ log N ≪ d ⩽ O ( log N ) .


Biometrics ◽  
2021 ◽  
Author(s):  
Xin Chen ◽  
Rui Song ◽  
Jiajia Zhang ◽  
Swann Arp Adams ◽  
Liuquan Sun ◽  
...  

Author(s):  
R.A. Abdulvaliyev ◽  
◽  
S.B. Dyussenova ◽  
A.I. Manapova ◽  
A. Akcil ◽  
...  

The known methods of processing low-quality bauxite have a number of disadvantages that make it difficult or impossible to use them in the conditions of production of JSC "Aluminum of Kazakhstan", therefore, it is necessary to effectively develop a technology for preliminary enrichment. Enrichment of low-quality bauxites is possible by separating the clayey - high-siliceous and coarse-crystalline fractions. Electron-microscopic analysis of the original bauxite showed that the coarse-crystalline fraction is tightly pressed by the fine one. The total silicon modulus of the sample is 2.49. The silicon modulus of the fine fraction is 2.19, and that of the coarse fraction is 3.89. When enriching bauxite, as a result of the separation of fines, it is possible to increase the silicon modulus. After the chemical activation of bauxite in a sodium bicarbonate solution, the finely dispersed fraction is effectively separated from the coarse one and the phase composition changes - the calcium silicate phase disappears and the calcite phase is formed. With an increase in the activation temperature, the content of kaolinite and siderite decreases, and the content of quartz and hematite increases. Studies have shown that at temperatures of chemical activation of 120 ° C, duration of more than 120 minutes and 200 ° C, duration of more than 40 minutes, a dawsonite phase is formed in bauxite, which densifies the mineral structure. When determining the optimal regime for carrying out chemical activation, it is necessary to take into account the negative possibility of dawsonite formation.


Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 772
Author(s):  
Vladimir Rodionov ◽  
Abdulkarim Amirov ◽  
Murad Annaorazov ◽  
Erkki Lähderanta ◽  
Alexander Granovsky ◽  
...  

We report the results of studies of the magnetic and transport properties of Fe49Rh51 alloy prepared by different sequences of quenching and the annealing process. The temperature dependences of the relative initial magnetic permeability and resistivity are analyzed. An optimal regime consisting of annealing at 1300 K for 440 min and quenching from 1300 K to 275 K is found to observe the desired narrow antiferromagnetic–ferromagnetic transition in Fe49Rh51 alloy under cyclic conditions. This has the potential to increase the efficiency of cooling devices based on the magnetocaloric effect of magnetic materials with a first-order field-induced phase transition.


2021 ◽  
Author(s):  
Ksenia Zlobina ◽  
Jiahao Xue ◽  
Marcella Gomez

Wound healing consists of a sequence of biological processes often grouped into different stages. Interventions applied to accelerate normal wound healing must take into consideration timing with respect to wound healing stages in order to maximize treatment effectiveness. Macrophage polarization from M1 to M2 represents a transition from the inflammatory to proliferation stage of wound healing. Accelerating this transition may be an effective way to accelerate wound healing; however, it must be induced at the appropriate time. We search for an optimal spatio-temporal regime to apply wound healing treatment in a mathematical model of wound healing. In this work we show that to maximize effectiveness, treatment must not be applied too early or too late. We also show that effective spatial distribution of treatment depends on the heterogenity of the wound surface. In conclusion, this research provides a possible optimal regime of therapy that focuses on macrophage activity and a hypothesis of treatment outcome to be tested experimentally in future. Finding best regimes for treatment application is a first step towards development of intelligent algorithms of wound treatment that minimize healing time.


Author(s):  
Marina V. Bykova ◽  
Alexey V. Alekseenko ◽  
Mariya A. Pashkevich ◽  
Carsten Drebenstedt

AbstractThe results of field, analytical, and experimental research at a number of production facilities reflect the properties of oil-contaminated soils in 3 landscapes: the permafrost treeless Arctic ecosystem, boreal forest, and temperate-climate grassland-woodland ecotone. Laboratory studies have revealed the concentrations of petroleum hydrocarbons in soils, ranging from medium levels of 2000–3000 mg/kg to critical figures over 5000 mg/kg, being 2–25 times higher than the permissible content of oil products in soils. The experimentally applied thermal effects for the oil products desorption from the soil allowed finding an optimal regime: the treatment temperature from 25 to 250 °C reduces the concentrations to an acceptable value. The conditions are environmentally sound, given that the complete combustion point of humates is ca. 450 °C. The outcomes suggest the eco-friendly solution for soil remediation, preserving the soil fertility in fragile cold environments and in more resilient temperate climates, where revitalized brownfields are essential for food production.


Tehnika ◽  
2021 ◽  
Vol 76 (5) ◽  
pp. 636-644
Author(s):  
Ivan Škiljaica ◽  
Vladimir Škiljaica ◽  
Mirjana Živković

The paper analyzes the navigating conditions of the displacement type ships for the transport of our shipping companies on the channels of the Danube-Tisa-Danube hydro system in order to determine the navigation speed at which the speeds of water flow of opposite direction occur so that the channel banks and the bottom are protected from collapse. The methods applied in the work were created as a result of special research conducted on the Moscow and Volga-Don channels by two scientific institutions of the Russian Federation: the Main Research Institute of Water Transport (GIIVT) and the Scientific Research Institute of Water Transport (NIIVT). The results of this research have been published in literature in the Russian language. The aim of the authors was, based on these published methods, to examine and determine the impact of the movement of ships of our shipping companies on the shores and bottom of the canal as a new step in preparations for finding the optimal regime of navigation on navigable canals. Self-propelled (motor) ships for the transport of cargo of different types in channels of variable cross-sectional area and at different navigation speeds were subjected to calculations.


2021 ◽  
Vol 406 ◽  
pp. 385-391
Author(s):  
Selma Attabi ◽  
Lakhdar Laouar ◽  
Madjda Mokhtari ◽  
Abdelaziz Himour ◽  
Hicham Elmsellem

In the field of mechanics and biomaterials, particular attention is directed to the finishing step of pieces because it conditions several properties of materials, namely surface quality and microhardness. The mechanical surface treatment (TMS) by burnishing is one among the most competent finishing operations aimed toward improving the characteristics of surface and also the lifetime of components. Although this treatment is extremely effective, but it is very necessary to choose the appropriate combination of process parameters to realize better results. This work aims to improve, by ball burnishing, the microhardness of 316L stainless steel used for the manufacture of biomedical hip prostheses. This property is vital because it directly influences other final properties such as tensile strength, wear resistance and fatigue life. The response surface method based on Box-Behnken model is followed for experiments and an empirical model expressing the relationship between microhardness and process parameters (burnishing force, feed rate, and ball diameter ) is developed. The optimal regime for maximum hardening is also established. The results show that burnishing treatment, carried out on a flat surface, makes it possible to significantly hardening the surface of 316L stainless steel by obtaining a greater value by up to 67% compared to the untreated surface. Scanning electron micrographs show a very thin surface layer containing grains deformed plastically in the burnishing direction.


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