scholarly journals Solid-liquid systems for the hydrolysis of glycoalkaloids from potato (Solanum tuberosum L) tuber sprouts and solanidine isolation

2003 ◽  
Vol 57 (6) ◽  
pp. 288-292
Author(s):  
Nada Nikolic ◽  
Mihajlo Stankovic ◽  
Milorad Cakic
Keyword(s):  
Solanum Tuberosum ◽  
Liquid Phase ◽  
Hydrochloric Acid ◽  
Solid Phase ◽  
Solanum Tuberosum L ◽  
Volume Ratio ◽  
Liquid Systems ◽  
Pharmacologically Active ◽  
Solid Liquid ◽  
Hydrolysis Of

Solanidine (C17H43O/V) is a steroidal aglycone of glycoalkaloids and an important precursor for the synthesis of hormones and some pharmacologically active compounds. Glycoalkaloids are hydrolysed by mineral acid yielding solanidine and a carbohydrate moiety. In this paper the kinetics of hydrolysis of glycoalkaloids from potato (Solanum tuberosum L) tuber sprouts by using solid-liquid systems were studied as well as solanidine isolation from the liquid phase of the system. The dried and milled tuber sprouts of potato were used as the solid phase and solutions of hydrochloric acid of different concentration in 96 % vol. ethanol, mixed with chloroform in a volume ratio of 2:3, 1:1, 3:2 and 4:1, were used as the liquid phase. The aim of the paper was to choose the optimal concentration of hydrochloric acid in ethanol, the volume ratio of hydrochloric acid in ethanol to chloroform in the liquid phase and the time for solanidine hydrolytic extraction, as well as to isolate solanidine from the liquid phase.

scholarly journals Kinetics of solanidine hydrolytic extraction from potato (Solanum tuberosum L) haulm solid-liquid systems

2003 ◽  
Vol 68 (1) ◽  
pp. 9-16 ◽  
Author(s):  
Nada Nikolic ◽  
Mihajlo Stankovic
Keyword(s):  
Solanum Tuberosum ◽  
Hydrochloric Acid ◽  
Solid Phase ◽  
Solanum Tuberosum L ◽  
Volume Ratio ◽  
Single Step ◽  
Ethanolic Solution ◽  
Liquid Systems ◽  
Solid Liquid ◽  
Kinetics Of

Dried and milled haulm of potato (Solanum tuberosum L) was used as the solid phase. An ethanolic solution of hydrochloric acid mixed with chloroform in different volume ratios was the liquid phase. The aim of paper was to unite in a single step the processes of glycoalkaloids extraction from haulm, their hydrolysis to solanidine and the extraction of solanidine. This could make the procedure of obtaining solanidine faster and simpler. The best degree of solanidine hydrolytic extraction of 84.5% was achieved using 10% w/v hydrochloric acid in 96% vol. ethanol mixed with chloroform in a volume ratio of 2:3, after 120 min of hydrolytic extraction.

Mesoscopic Models of Liquid/Solid Phase Transitions

1998 ◽  
Vol 09 (08) ◽  
pp. 1405-1415 ◽  
Author(s):  
G. de Fabritiis ◽  
A. Mancini ◽  
D. Mansutti ◽  
S. Succi
Keyword(s):  
Phase Transitions ◽  
Liquid Phase ◽  
Mushy Zone ◽  
Lattice Boltzmann ◽  
Solid Phase ◽  
Chaotic Motions ◽  
Computational Costs ◽  
Mesoscopic Models ◽  
Lattice Boltzmann Models ◽  
Solid Liquid

A generalization of mesoscopic Lattice-Boltzmann models aimed at describing flows with solid/liquid phase transitions is presented. It exhibits lower computational costs with respect to the numerical schemes resulting from differential models. Moreover it is suitable to describe chaotic motions in the mushy zone.

scholarly journals Solid-liquid phase equilibria of (H2O-Mn(H2PO2)2-MnCl2-NaCl), (H2O-Mn(H2PO2)2-MnCl2) and (H2O-NaCl- MnCl2) systems at 323.15 K

2020 ◽  
pp. 59-59
Author(s):  
Vedat Adiguzel ◽  
Wei Liu ◽  
Asadullah Memon ◽  
Hongtao Zhou ◽  
Imran Akbar ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Phase Equilibria ◽  
Quaternary System ◽  
Invariant Point ◽  
Solid Phase ◽  
Ternary Systems ◽  
Invariant Curves ◽  
Saturation Method ◽  
Solid Liquid ◽  
Liquid And Solid Phases

The solid-liquid phase equilibria (SLE) and densities of H2O-NaCl- -MnCl2-Mn(H2PO2)2 quaternary system, H2O-NaCl-MnCl2 and H2O-MnCl2- -Mn(H2PO2)2 ternary systems were investigated at 323.15 K by the isothermal solution saturation method. The analyses of the liquid and solid phases were used to determine the composition of the solid phase using the Schreinemakers graphic method. The ternary systems contain one invariant point, two invariant curves and two crystallization regions. In the quaternary system, there is one invariant point, three invariant curves, and three crystallization areas corresponding to NaCl, MnCl2 4H2O, and Mn(H2PO2)2H2O. The crystallization area of Mn(H2PO2)2 H2O, being the largest in comparison with those of other salts, occupied 80.75 % of the total crystallization area.

scholarly journals The Simulation of the Preparation of the Ingot With Liquid Core

2021 ◽  
Author(s):  
yongqiang wu ◽  
Zhi-ren Sun ◽  
Kaikun Wang
Keyword(s):  
Finite Element ◽  
High Temperature ◽  
Liquid Phase ◽  
Solid Phase ◽  
Liquid Core ◽  
Phase Region ◽  
Simulation Results ◽  
Solid Liquid ◽  
Deform 3D ◽  
Ultra High Temperature

Abstract During the preparation of the ingot with liquid core in the early stage, the finite element models of the solidification and the ultra-high temperature demoulding were established in DEFORM-3D. The thermophysical properties of ASSAB 718 with the variations of C, Mn and Cr were calculated in JMatPro®. The material database was imported into DEFORM-3D. Through the analysis of the finite element simulation results, we obtained the influence of three main elements C, Mn and Cr contents on the size of the solid-phase region, the liquid-phase region and the solid-liquid two-phase region in the ingot. We optimized the composition of the material to get a wide solid-liquid phase range. The high carbon, the medium manganese and the high chromium contents were beneficial to form the liquid core. Based on the method of the solidification time, the algorithm was programmed by the python language. We analyzed the influence of the three elements C, Mn, and Cr on the concentration distribution based on the temperature field data, which were obtained by DEFORM-2D after the solidification and the ultra-high temperature demoulding. According to the simulation results, we found that the region prone to negative segregation.

Energy Storage With Solid/Liquid Phase Change in Presence of Natural Convection

2001 ◽  
Author(s):  
M. Pinelli ◽  
S. Piva
Keyword(s):  
Natural Convection ◽  
Energy Storage ◽  
Liquid Phase ◽  
Phase Change ◽  
Change Process ◽  
Solid Phase ◽  
High Energy ◽  
Heat Transfer Process ◽  
Phase Change Process ◽  
Solid Liquid

Abstract Solid/liquid phase change process has received great attention for its capability to obtain high energy storage efficiency. In order to analyse these systems, undergoing a solid/liquid phase change, in many situations the heat transfer process can be considered conduction-dominated. However, in the past years, it has been shown that natural convection in the liquid phase can significantly influence the phase change process in terms of temperature distributions, interface displacement and energy storage. In this paper, a procedure to analyse systems undergoing liquid/solid phase change in presence of natural convection in the liquid phase based on the utilisation of a commercial computer code (FLUENT), has been developed. This procedure is applied to a cylinder cavity heated from above and filled with a Phase Change Material. It was found that when the coupling with the environment, even if small, is considered, natural convection in the liquid phase occurs. The numerical results are then compared with available experimental data. The analysis shows that the agreement between numerical and experimental results is significantly improved when the results are obtained considering the presence of circulation in the liquid phase instead of considering the process only conduction-dominated. Furthermore, some interesting features of the flow field are presented and discussed.

Realistic coagulation mechanisms in the use of aluminium and iron(III) salts

1997 ◽  
Vol 36 (4) ◽  
pp. 103-110 ◽  
Author(s):  
István Licskó
Keyword(s):  
Phase Separation ◽  
Liquid Phase ◽  
Suspended Solids ◽  
Liquid Phase Separation ◽  
Metal Hydroxide ◽  
Water Soluble ◽  
Short Period ◽  
Rapid Hydrolysis ◽  
Solid Liquid ◽  
Hydrolysis Of

The processes leading from coagulant feed to the development of flocs suited to solid-liquid phase separation are examined and analyzed in the light of available information and experimental data. It is concluded that at the relatively high buffering capacity (HCO3− concentration above 1.8 meg/L) and close to neutral pH values (7.0<pH<8.4) typically found in the surface waters of Hungary, flocs suited to solid-liquid phase separation develop from the coagulant added within a very short period of time (10-20 seconds). These flocs are not capable of changing the charge of the particles on the colloidal, quasi-colloidal, or destabilizing the dispersion. Between the hydrolysis of the coagulant and the development of large flocs, “short-lived” water soluble aluminium and iron(III) hydroxide complexes, metal hydroxide sols are formed, which also carry a positive charge. These latter two metal hydroxide types (which also exist for a brief period - a few seconds - only) are the ones capable of destabilizing the dispersion. The bond between the suspended solids to be removed and the metal hydroxide sols and water soluble metal hydroxide complexes must be established within this short period. Rapid mixing of the coagulant will ensure rapid hydrolysis of the coagulant, contact between the sols and the suspended solids and will retard the development of large flocs which are inactive in destabilizing the dispersion.

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