SURFACE TENSION OF SODIUM SOAP DISPERSIONS IN MINERAL OILS

1943 ◽  
Vol 21b (11) ◽  
pp. 225-229 ◽  
Author(s):  
Wilfred Gallay ◽  
Ira E. Puddington
Keyword(s):  
Surface Tension ◽  
Melting Point ◽  
Surface Activity ◽  
Viscosity Index ◽  
Sodium Stearate ◽  
Melting Points ◽  
Mineral Oils ◽  
Low Viscosity ◽  
Wide Range ◽  
High Polarity

The surface tension of sodium stearate and sodium oleate dispersions in mineral oils of high and low viscosity index has been measured over a wide range of temperature. In dispersions in the non-polar oil, no surface activity is shown by the soap until the full melting point is reached. In dispersions in an oil of relatively high polarity, surface activity is shown at much lower temperatures corresponding to partial melting points of the soaps. The ability of the soap to lower the surface tension is dependent on the degree of dispersion of the soap, and the relation of surface activity to physical states and phase transitions, previously determined by the authors, is discussed. The addition of glycerol increases the surface activity at a given concentration, but the temperature at which surface activity is attained remains unaffected. Excess fatty acid acts similarly to glycerol; excess alkali decreases surface activity.

THE EFFECT OF CERTAIN ADDITION AGENTS ON THE PHYSICAL STATES OF SODIUM SOAPS

1943 ◽  
Vol 21b (10) ◽  
pp. 211-218 ◽  
Author(s):  
Wilfred Gallay ◽  
Ira E. Puddington
Keyword(s):  
Melting Point ◽  
Sodium Oleate ◽  
Polar Solvent ◽  
Sodium Stearate ◽  
Hydrocarbon Chain ◽  
Polar Solvents ◽  
Inert Diluent ◽  
Mineral Oils ◽  
Orienting Effect

The effect of glycerol and of polar and non-polar mineral oils on the density–temperature relations of sodium stearate and sodium oleate have been measured. A non-polar solvent such as a high V.I. oil has no effect, and may be regarded as an inert diluent. Glycerol and low V.I. oils have similar effects on the physical states of the soap. Up to the unidimensional melting point of the soap, the polar solvents have no effect. Above this point, however, an increasing effect is obtained both with increase in temperature and with amount of solvent. The effect is particularly marked above the plasticity point but may be large also in the region of the bidimensional melting point of the soap. The orienting effect of the non-polar hydrocarbon chain on the polar grouping of the soap in the presence of a polar solvent is discussed. The influence of excess acid and alkali in the soap is described.

The Use of Styrenes as Embedding Media for Electron Microscopy

1971 ◽  
Vol 29 ◽  
pp. 488-489
Author(s):  
Edward D. De-Lamater ◽  
Eric Johnson ◽  
Thad Schoen ◽  
Cecil Whitaker
Keyword(s):  
Electron Microscopy ◽  
Surface Tension ◽  
Ultraviolet Light ◽  
Methyl Ethyl Ketone Peroxide ◽  
Methyl Ethyl ◽  
Styrene Polymerization ◽  
Radical Initiation ◽  
Tertiary Butyl ◽  
Low Viscosity ◽  
Free Radical Initiation

Monomeric styrenes are demonstrated as excellent embedding media for electron microscopy. Monomeric styrene has extremely low viscosity and low surface tension (less than 1) affording extremely rapid penetration into the specimen. Spurr's Medium based on ERL-4206 (J.Ultra. Research 26, 31-43, 1969) is viscous, requiring gradual infiltration with increasing concentrations. Styrenes are soluble in alcohol and acetone thus fitting well into the usual dehydration procedures. Infiltration with styrene may be done directly following complete dehydration without dilution.Monomeric styrenes are usually inhibited from polymerization by a catechol, in this case, tertiary butyl catechol. Styrene polymerization is activated by Methyl Ethyl Ketone peroxide, a liquid, and probably acts by overcoming the inhibition of the catechol, acting as a source of free radical initiation.Polymerization is carried out either by a temperature of 60°C. or under ultraviolet light with wave lengths of 3400-4000 Engstroms; polymerization stops on removal from the ultraviolet light or heat and is therefore controlled by the length of exposure.

scholarly journals Surface Activity of Humic Acid and Its Sub-Fractions from Forest Soil

2021 ◽  
Vol 13 (15) ◽  
pp. 8122
Author(s):  
Shijie Tian ◽  
Weiqiang Tan ◽  
Xinyuan Wang ◽  
Tingting Li ◽  
Fanhao Song ◽  
...  
Keyword(s):  
Surface Tension ◽  
Particle Size ◽  
Humic Acid ◽  
Forest Soil ◽  
Surface Activity ◽  
Self Assembly ◽  
Average Particle Size ◽  
Gaussian Model ◽  
Exponential Model ◽  
Average Particle

Surface activity of humic acid (HA) and its six sub-fractions isolated from forest soil were characterized by surface tension measurements, dynamic light scattering, and laser doppler electrophoresis. The surface tension of HA and its sub-fractions reduced from 72.4 mN·m−1 to 36.8 mN·m−1 in exponential model with the increasing concentration from 0 to 2000 mg·L−1. The critical micelle concentration (CMC) and Z-average particle size ranged from 216–1024 mg·L−1 and 108.2–186.9 nm for HA and its sub-fractions, respectively. The CMC have related with alkyl C, O-alkyl C, aromatic C, and carbonyl C (p < 0.05), respectively, and could be predicted with the multiple linear regression equation of CMC, CMC = 18896 − 6.9 × C-296 × alkyl C-331 × aromatic C-17019 × H/C + 4054 × HB/HI (p < 0.05). The maximum particle size was 5000 nm after filtered by a membrane with pore size of 450 nm, indicating HA and its sub-fractions could progressed self-assembly at pH 6.86. The aggregate sizes of number-base particle size distributions were mainly in six clusters including 2 ± 1 nm, 5 ± 2 nm, 10 ± 3 nm, 21 ± 8 nm, 40 ± 10 nm, and >50 nm analyzed by Gaussian model that maybe due to the inconsistency of the components and structures of the HA sub-fractions, requiring further study. It is significance to explore the surface activity of HA and its sub-fractions, which is helpful to clarify the environmental behavior of HA.

Predictions of Current Attachment at Thermionic Cathode for TIG Arcs

2008 ◽  
Vol 580-582 ◽  
pp. 319-322 ◽  
Author(s):  
Manabu Tanaka ◽  
Kentaro Yamamoto ◽  
Tashiro Shinichi ◽  
John J. Lowke
Keyword(s):  
Melting Point ◽  
Work Function ◽  
Atmospheric Pressure ◽  
The Other ◽  
Numerical Calculations ◽  
Maximum Temperature ◽  
Arc Plasma ◽  
Melting Points ◽  
Thermionic Cathode ◽  
Uniform Current

Study of current attachment at thermionic cathode for TIG arc at atmospheric pressure is attempted from numerical calculations of arc-electrodes unified model. The calculations show that the maximum temperature of arc plasma close to the cathode tip for W-2% ThO2 reaches 19,000 K and it is the highest value in comparison with the other temperatures for W-2% La2O3 and W-2% CeO2, because the current attachment at the cathode tip is constricted by a centralized limitation of liquid area of ThO2 due to its higher melting point. The calculations also show that, in cases of W- 2% La2O3 and W-2% CeO2, the liquid areas of La2O3 and Ce2O3 are widely expanded at the cathode tip due to their lower melting points and then produce uniform current attachments at the cathode. It is concluded that the current attachment at thermionic cathode is strongly dependent on work function, melting point and Richardson constant of emitter materials.

FLOW-PRESSURE RELATIONS IN CALCIUM-SOAP–OIL SYSTEMS

1946 ◽  
Vol 24b (3) ◽  
pp. 73-80
Author(s):  
Wilfred Gallay ◽  
Ira E. Puddington
Keyword(s):  
Viscosity Index ◽  
Calcium Soap ◽  
Mineral Oils ◽  
Yield Value ◽  
Flow Pressure ◽  
Varying Viscosity

Flow–pressure relations have been determined for suspensions of calcium soaps in mineral oils of varying viscosity and viscosity index. The effect of small amounts of reagents on the character of these curves is very marked. The addition of water generally increases the yield value of the system without affecting the mobility, while solvents for calcium soaps tend to change the mobility without altering the yield value.

Synthesis of high viscosity index base stock and study on the lubricating properties

2016 ◽  
Vol 68 (1) ◽  
pp. 52-56 ◽  
Author(s):  
Weiwei Wang ◽  
Shan Jiang ◽  
Yan Shen ◽  
Shunba Xia ◽  
Jiujun Xu
Keyword(s):  
Ionic Liquid ◽  
Reaction Time ◽  
Viscosity Index ◽  
Content Type ◽  
Group I ◽  
Film Forming ◽  
Wide Range ◽  
Catalyst Dosage ◽  
Group Ii ◽  
Lubricating Properties

Purpose – This paper aims to address the polymerization of 1-decene by [Emim]Cl/AlCl3 ionic liquid and the film-forming properties of the product compared with commercially available base stocks. Design/methodology/approach – Experiments were carried out to investigate the influence of [Emim]Cl/AlCl3 mole ratio, catalyst dosage, reaction temperature, reaction time and water on the polyreaction. Poly alpha-olefin (PAO) is prepared under optimal reaction condition. Film-forming properties of PAO have been compared with those of Group I, Group II and Group III base stocks, which are selected with approximately the same viscosity. Findings – Experimental results show that after a 4-h reaction time, yield of PAO can be higher than 85 per cent and viscosity index can be up to 160 with [Emim] Cl/AlCl3 mole ratio of 2:1, catalyst dosage of 3 per cent wt. and water content of 20 ppm. A strong influence of water on reaction is observed. With approximately the same viscosity, PAO shows the superiority in film thickness at low-sliding speeds compared with Group I and Group II base stocks. At high temperature, PAO provides a thicker film than other base stocks. Originality/value – In recent years, there has been considerable interest in ionic liquids. As a novel catalyst, it has so many advantages including low corrosion, low toxicity, low cost and a potentially wide range of properties compared with traditional catalysts. This paper reports the polymerization of 1-decene by [Emim]Cl/AlCl3 ionic liquid and the study on lubricating properties of PAO compared with mineral base stocks.

Surface Activity Research of Cationic Gemini Surfactants

2013 ◽  
Vol 690-693 ◽  
pp. 2076-2080
Author(s):  
Zhen Zhong Fan ◽  
Lan Lan Li ◽  
Li Feng Zhang ◽  
Qing Wang Liu
Keyword(s):  
Surface Tension ◽  
Critical Micelle Concentration ◽  
Surface Activity ◽  
Surfactant Concentration ◽  
Gemini Surfactant ◽  
Gemini Surfactants ◽  
Ph Value ◽  
Inorganic Salts ◽  
Cationic Gemini Surfactant ◽  
Cationic Gemini Surfactants

Cationic Gemini surfactant concentration, the inorganic salts added and the pH value of surface tension obtained cationic gemini surfactant critical micelle concentration is 0.4mmol / L;by adding three kinds of inorganic salts NaCl, MgCl2, and Na2SO4 ,which Na2SO4 has the greatest impact on surface tension, followed by MgCl2.The surface minimum tension of the pH ranged from 9 to 11 , indicating that the surface activity of cationic gemini surfactants achieved the highest.

Use of Polymers in Viscosity Index Modification of Mineral Oils and Pour Point Depression of Vegetable Oils

2017 ◽  
pp. 61-89
Author(s):  
Dogan Grunberg ◽  
Mert Arca ◽  
Dan Vargo ◽  
Sevim Z. Erhan ◽  
Brajendra K. Sharma
Keyword(s):  
Vegetable Oils ◽  
Pour Point ◽  
Viscosity Index ◽  
Mineral Oils

scholarly journals Cavity Detachment from a Wedge with Rounded Edges and the Surface Tension Effect

2021 ◽  
Vol 9 (11) ◽  
pp. 1253
Author(s):  
Yuriy N. Savchenko ◽  
Georgiy Y. Savchenko ◽  
Yuriy A. Semenov
Keyword(s):  
Surface Tension ◽  
Weber Number ◽  
Solution Process ◽  
Cavity Flow ◽  
Surface Tension Effect ◽  
Force Coefficient ◽  
Hodograph Method ◽  
Wide Range ◽  
Critical Weber Number ◽  
Cavity Boundary

Cavity flow around a wedge with rounded edges was studied, taking into account the surface tension effect and the Brillouin–Villat criterion of cavity detachment. The liquid compressibility and viscosity were ignored. An analytical solution was obtained in parametric form by applying the integral hodograph method. This method gives the possibility of deriving analytical expressions for complex velocity and for potential, both defined in a parameter plane. An expression for the curvature of the cavity boundary was obtained analytically. By using the dynamic boundary condition on the cavity boundary, an integral equation in the velocity modulus was derived. The particular case of zero surface tension is a special case of the solution. The surface tension effect was computed over a wide range of the Weber number for various degrees of cavitation development. Numerical results are presented for the flow configuration, the drag force coefficient, and the position of cavity detachment. It was found that for each radius of the edges, there exists a critical Weber number, below which the iterative solution process fails to converge, so a steady flow solution cannot be computed. This critical Weber number increases as the radius of the edge decreases. As the edge radius tends to zero, the critical Weber number tends to infinity, or a steady cavity flow cannot be computed at any finite Weber number in the case of sharp wedge edges. This shows some limitations of the model based on the Brillouin–Villat criterion of cavity detachment.

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