scholarly journals The FMO Complex in a Glycerol–Water Mixture

2013 ◽  
Vol 117 (24) ◽  
pp. 7157-7163 ◽  
Author(s):  
Mortaza Aghtar ◽  
Johan Strümpfer ◽  
Carsten Olbrich ◽  
Klaus Schulten ◽  
Ulrich Kleinekathöfer
Keyword(s):  
Water Mixture ◽  
Glycerol Water

HYDROTHERMAL SYNTHESIS OF CALCIUM HYDROSILICATES

1934 ◽  
Vol 11 (4) ◽  
pp. 520-529 ◽  
Author(s):  
V. A. Vigfusson ◽  
G. N. Bates ◽  
T. Thorvaldson
Keyword(s):  
Hydrothermal Synthesis ◽  
Silica Gel ◽  
Fused Silica ◽  
Steam Treatment ◽  
Crystalline Substance ◽  
Water Mixture ◽  
Glycerol Water ◽  
X Ray ◽  
Lime Water ◽  
Calcium Hydrosilicate

A crystalline substance which appears in steam-cured Portland cement mortar has been shown to be a calcium hydrosilicate and has been prepared by hydrothermal synthesis from mixtures of silica sand with lime, dicalcium silicate and tricalcium silicate, silica gel and lime (after preliminary steam treatment and ignition) and by the action of saturated lime water on quartz crystals or fused silica plates. The crystals appear not to be acted on by solutions of sodium sulphate, calcium sulphate or alkali hydroxides, but they are slowly decomposed by solutions of magnesium sulphate and alkali carbonates and rapidly by dilute acids and ammonium salts. The crystals were obtained free from amorphous matter by growing them on quartz or silica plates in saturated lime water. When the compound was prepared in this way, the lime-silica-water ratio was found to be 2:1:1, the formula being therefore 2CaO∙SiO2∙H2O or H2Ca2SiO5. This product usually appears as thin lath-like prisms showing parallel extinction, positive elongation and moderate birefringence. The crystals are optically positive with a fairly large optic angle. 2V = 68°. The indices of refraction are αNa = 1.614 ±.002, βNa = 1.620 ±.002, γNa = 1.633 ±.002. The optical plane is parallel to the macropinacoid (100) and the acute bisectrix Z is parallel to the direction of elongation which is taken as the crystallographic axis C. The optical properties and X-ray pattern are distinctive and entirely different from those of hillebrandite or foshagite, which have the same composition.Another crystalline calcium hydrosilicate was obtained by hydrothermal synthesis from excess lime and silica gel. This appeared as very small needle-like prisms, observable only when magnified about 200 times. The crystals show parallel extinction, positive elongation and very low birefringence with an index of refraction of 1.597 ±.003. Analysis of this product, extracted with a glycerol-water mixture to remove excess lime, gave a lime-silica ratio of 2 to 1 with an uncertain amount of water of at least one mole. The X-ray pattern is distinctive and shows only slight similarity to the hillebrandite pattern.

Experimental and CFD Investigations of Heat Transfer in Helical Coils for the Development of Correlations for Newtonian and Non-Newtonian Fluids in Transient State-Space Conditions

2013 ◽  
Author(s):  
Sandipan S. Pawar ◽  
Vivek K. Sunnapwar ◽  
Vivek K. Yakkundi
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Turbulent Flow ◽  
Transfer Coefficient ◽  
Flow Regimes ◽  
Newtonian Fluids ◽  
Water Mixture ◽  
Glycerol Water ◽  
Laminar And Turbulent Flow ◽  
Helical Coils

Experimental studies and CFD investigations were carried out under laminar and turbulent flow regimes in isothermal steady state and non-isothermal unsteady state conditions in helical coils for Newtonian and non-Newtonian fluids. Water and glycerol-water mixture (10 and 20 % glycerol) as Newtonian fluids and dilute aqueous polymer solutions of sodium carboxymethyl cellulose (SCMC), sodium alginate (SA) as non-Newtonian fluids were used in this study. The experiments were performed for three helical coils of coil curvature ratios as 0.0757, 0.064 and 0.055 in laminar and turbulent flow regimes. For the first time, two innovative correlations to calculate Nusselt number (Nu) in terms of new dimensionless ‘M’ number, Prandtl number and coil curvature ratio under different conditions for Newtonian fluids are proposed in this paper. Third correlation of Nu vs. Graetz number (Gz) including the effects of coil curvature on heat transfer coefficient which was not considered by earlier investigators is developed based on tests conducted in laminar flow for Newtonian fluids. All these three innovative correlations developed based on experimental data which were not found in the literature. These correlations were compared with the work of earlier investigators and were found to be in good agreement. The CFD analysis for laminar and turbulent flow was carried out using the CFD package FLUENT 12.0.16. The CFD calculation results (Nui, U) for laminar and turbulent flows were compared with the experimental results, and also the work of earlier investigators was found to be in excellent agreement. Further, the effect of helix diameter on heat transfer for Newtonian and Non-Newtonian fluids are also presented in this paper and it was observed that as helix diameter increases, overall heat transfer coefficient decreases.

Preference for Isolated Water Molecules in a Concentrated Glycerol–Water Mixture

2011 ◽  
Vol 115 (24) ◽  
pp. 7799-7807 ◽  
Author(s):  
J. J. Towey ◽  
A. K. Soper ◽  
L. Dougan
Keyword(s):  
Water Molecules ◽  
Water Mixture ◽  
Glycerol Water

scholarly journals Influence of bubble content on laser-induced cavitation bubble oscillation in glycerol-water mixture

2009 ◽  
Vol 58 (12) ◽  
pp. 8400
Author(s):  
Zhao Rui ◽  
Xu Rong-Qing ◽  
Liang Zhong-Cheng ◽  
Lu Jian ◽  
Ni Xiao-Wu
Keyword(s):  
Cavitation Bubble ◽  
Water Mixture ◽  
Glycerol Water ◽  
Bubble Oscillation

Properties of low-temperature spectral relaxation of eosin phosphorescence in a glycerol-water mixture

2000 ◽  
Vol 88 (3) ◽  
pp. 346-351 ◽  
Author(s):  
A. V. Pastukhov ◽  
V. R. Fogel’ ◽  
A. I. Kotel’nikov
Keyword(s):  
Low Temperature ◽  
Water Mixture ◽  
Glycerol Water ◽  
Spectral Relaxation

scholarly journals Diffusion in Glycerol-Water Mixture

1960 ◽  
Vol 33 (12) ◽  
pp. 1649-1651 ◽  
Author(s):  
Yasunori Nishijima ◽  
Gerald Oster
Keyword(s):  
Water Mixture ◽  
Glycerol Water

scholarly journals Superspreading on Hydrophobic Substrates: Effect of Glycerol Additive

2019 ◽  
Vol 3 (2) ◽  
pp. 51 ◽  
Author(s):  
Nina M. Kovalchuk ◽  
Jacques Dunn ◽  
Jack Davies ◽  
Mark J. H. Simmons
Keyword(s):  
Silicone Oil ◽  
Water Mixture ◽  
Marangoni Flow ◽  
Glycerol Content ◽  
Complete Wetting ◽  
Glycerol Water ◽  
Left Behind ◽  
Surfactant Solutions ◽  
Trisiloxane Surfactants ◽  
Equilibration Rate

The spreading of solutions of three trisiloxane surfactants on two hydrophobic substrates, polyethylene and polyvinylidenefluoride, was studied with the addition of 0–40 mass % of glycerol. It was found that all the surfactant solutions spread faster than silicone oil of the same viscosity, confirming the existence of a mechanism which accelerates the spreading of the surfactant solutions. For the non-superspreading surfactant, BT-233, addition of glycerol improved the spreading performance on polyvinylidenefluoride and resulted in a transition from partial to complete wetting on polyethylene. The fastest spreading was observed for BT-233 at a concentration of 2.5 g/L, independent of glycerol content. For the superspreading surfactants, BT-240 and BT-278, the concentration at which the fastest spreading occurs systematically increased with concentration of glycerol on both substrates from 1.25 g/L for solutions in water to 10 g/L for solutions in 40% glycerol/water mixture. Thus, the surfactant equilibration rate (and therefore formation of surface tension gradients) and Marangoni flow are important components of a superspreading mechanism. De-wetting of the solutions containing glycerol, once spread on the substrates, resulted in the formation of circular drop patterns. This is in contrast to the solely aqueous solutions where the spread film shrank due to evaporation, without any visible traces being left behind.

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