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Article
Publication date: 18 February 2019

Fen Peng, Wensheng Liu, Yufeng Huang, Siwei Tang, Chaoping Liang and Yunzhu Ma

The purpose of this study is to develop a monolayer surface coating of stearic acid on Sn-Ag-Cu solder powder to limit oxidation.

Abstract

Purpose

The purpose of this study is to develop a monolayer surface coating of stearic acid on Sn-Ag-Cu solder powder to limit oxidation.

Design/methodology/approach

Stearic acid was adsorbed onto Sn-Ag-Cu solder powder through liquid-phase adsorption. The isotherm of adsorption was measured and then the microstructure of coated powder was characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy.

Findings

The adsorption isotherm of stearic acid on the powder was “H” type, which revealed the layer-by-layer adsorption on non-porous surface. When the concentration of solution was in the range of 0.001-0.006 mol/L, with an adsorption amount of 0.12 ± 0.1 mg/g, monolayer stearic acid covered the solder powder completely. Uniform and integrated self-assembled monolayer coating was formed through hydrogen bonds between the oxygen ions in surface lattice of Sn3.0Ag0.5Cu solder powder and the —O—H hydroxyl group of stearic acid. The maximum angle of stability of coated powder also reduced by 2.87° compared with that of non-coated powder. The increase rate of oxygen content of coated powder was much slower than that of non-coated powder when they were exposed to humid air.

Originality/value

As a result, oxidation of fine solder powder was effectively limited. Essentially, this method can also be applied to the coating of other types of solder powder and has reference significance to other coating by liquid-phase method.

Details

Soldering & Surface Mount Technology, vol. 31 no. 1
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 1 May 1991

Edgar S. Lower

A number of derivatives of vegetable and animal oils and fats are useable in the processing of rubbers, including fatty acids, fatty acid amides, amines, metallic soaps…

Abstract

A number of derivatives of vegetable and animal oils and fats are useable in the processing of rubbers, including fatty acids, fatty acid amides, amines, metallic soaps, and sulphur containing materials, etc.

Details

Pigment & Resin Technology, vol. 20 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 March 1992

A number of oleochemicals have found application in the formulation of metal processing lubricants. Calcium palmitate can act as a gelling inhibitor for lubricants for…

Abstract

A number of oleochemicals have found application in the formulation of metal processing lubricants. Calcium palmitate can act as a gelling inhibitor for lubricants for non‐chip metal forming, and diglyceryl oleate and sodium oleyl sulphate have been employed in chipless forming and machining lubricants. Glyceryl monooleate has been used together with paraffin wax and xylene for forming aluminium sheets, and isopropyl oleate has been blended into lubricants for cold forming of metal. Lubrication in cold forming of steel and aluminium alloys has been promoted by the use of sodium stearate and phosphating processes. Stearic acid has also been utlized in metal forming. Butyl butanamine stearamide is applicable in lubricants for non‐ferrous metal working, and coatings that can prevent galling when titanium is cold worked can be formed on the metal by the use of 0.5 grams of hydrofluoric acid, with 10 grams stearic acid in 100 ml. of a solvent, the process being accelerated by the inclusion of phosphoric acid at 0.85 grams. Calcium stearate has also been used in solvent‐based metalworking Iubricants, in acrylic electrophoretic lubricant coatings on metal, and in bentonite‐containing metalworking oils. Mixtures of cetyl alcohol and tricresyl phosphate have been cast into slabs and used on metalworking tools.

Details

Industrial Lubrication and Tribology, vol. 44 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 December 2000

Geetha C. Jayan and Joseph H. Herbein

The purposes of this study were to identify exogenous factors that would depress synthesis of saturated fats and enhance synthesis of unsaturated fats in the dairy cow’s…

Abstract

The purposes of this study were to identify exogenous factors that would depress synthesis of saturated fats and enhance synthesis of unsaturated fats in the dairy cow’s mammary gland. Certain long‐chain exogenous fatty acids are known to modulate endogenous fat synthesis within tissues. We analyzed the effects of two different long‐chain monounsaturated fatty acids, namely oleic acid and trans‐vaccenic acid (TVA), on activities of acetyl‐CoA carboxylase (ACC), fatty acid synthetase (FAS) and stearoyl‐CoA desaturase (SCD) in bovine mammary epithelial cell cultures. The study was done using an established bovine mammary epithelial cell line, the MacT cells. ACC (EC 6.4.1.2) and FAS (EC 2.3.1.85) are two major enzymes involved in biosynthesis of saturated fatty acids in eucaryotic cells. SCD (EC 1.14.99.5) is the enzyme catalyzing the critical committed step in biosynthesis of unsaturated fatty acids from their saturated precursors. Data indicated depression of activity of enzymes responsible for mammary synthesis of saturated fatty acids (ACC and FAS), along with a simultaneous enhancement of mammary desaturase activity, by TVA.

Details

Nutrition & Food Science, vol. 30 no. 6
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 17 August 2018

Hongjin Zhao, Lei Cao, Yong Wan, Shuyan Yang, Jianguo Gao and Jibin Pu

The purpose of this paper is to increase wear resistance of aluminum.

Abstract

Purpose

The purpose of this paper is to increase wear resistance of aluminum.

Design/methodology/approach

The authors have studied the ways to improve the tribological performance of aluminum by assembling stearic acid on aluminum coated by sol-gel-derived TiO2 film. The samples were characterized by infrared spectroscopy, contact angle measurements and a macro friction and wear tester.

Findings

Enhanced wear resistance was clearly obtained after functionalization of TiO2 film on aluminum by stearic acid.

Originality/value

The relevant results might be helpful for guiding the surface modification of aluminum devices in industrial applications.

Details

Industrial Lubrication and Tribology, vol. 70 no. 8
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 April 1980

N. Krishnamurti

Sixteen different vinyl monomers were synthesised, based on 12‐hydroxy stearic acid in high purity. These include allyl, acrylic and methacrylic esters. These monomers…

Abstract

Sixteen different vinyl monomers were synthesised, based on 12‐hydroxy stearic acid in high purity. These include allyl, acrylic and methacrylic esters. These monomers were characterised by infra red spectroscopy and their purity was checked by chromatographic techniques. Boiling/melting points, refractive indices and iodine values of the products have been determined.

Details

Pigment & Resin Technology, vol. 9 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 5 September 2016

Peng Yin, Can Xue and Bin Guo

The purpose of this paper is to study the influence of different carbon chain lengths in coupling agents on the water resistance and compatibility of modified long…

Abstract

Purpose

The purpose of this paper is to study the influence of different carbon chain lengths in coupling agents on the water resistance and compatibility of modified long afterglow phosphors and attempt to obtain their modification model and mechanism.

Design/methodology/approach

Three saturated-fatty-acid (caprylic, lauric, stearic acid)-based Al-Zr CAs (coupling agent) was synthesised and applied to modify the long afterglow phosphors SrMgAl4O8:Eu2+,Dy3+.

Findings

Results show that the coated amount on phosphors decreased from 13.41 to 6.53 per cent with the increased carbon chain length of fatty acid, and the better water resistant and suitability with organic resin can be obtained by lauric-based Al-Zr CA.

Originality/value

Considering that the decomposition process of modified phosphor was related with the decomposition performance of corresponding coupling agents and original phosphor, a method was first proposed to calculate the coated amount on phosphors by thermogravimetric analyser parameters.

Details

Pigment & Resin Technology, vol. 45 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 30 October 2009

Narasimhanaidu Kamalakkannan and Khalid S. Alnumair

The purpose of this paper is to explore the role of rutin, a polyphenolic flavonoid on the fatty acid composition in liver and kidney of streptozotocin (STZ)‐induced diabetic rats.

Abstract

Purpose

The purpose of this paper is to explore the role of rutin, a polyphenolic flavonoid on the fatty acid composition in liver and kidney of streptozotocin (STZ)‐induced diabetic rats.

Design/methodology/approach

Extensive literature review was carried out and no reports on the effect of rutin on the fatty acid composition in diabetic tissues were found.

Findings

Streptozotocin‐induced diabetic rats showed altered lipid concentration in liver and kidney. The fatty acid composition was also altered in these tissues. Treatment with rutin to diabetic rats significantly decreased the concentration of palmitic acid, stearic acid and oleic acid, whereas linolenic and arachidonic acids were significantly increased in liver and kidney of diabetic rats. Rutin administration to normal rats did not show any significant effect on the fatty acid composition in liver and kidney.

Originality/value

This paper gives an idea of the changes in the fatty acid composition of diabetic tissues and during treatment with rutin.

Details

Nutrition & Food Science, vol. 39 no. 6
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 1 June 1992

Edgar S. Lower

Polymers which do not normally dissolve in water can usually be dispersed in sodium oleate solutions, the polymer adsorbing surfactant to give a complex similar to polymer…

Abstract

Polymers which do not normally dissolve in water can usually be dispersed in sodium oleate solutions, the polymer adsorbing surfactant to give a complex similar to polymer electrolytes. Molten palmitic acid will serve as a solvent in which to polymerise acrylic compounds, and benzyl butyrate has been examined as a solvent in which to polymerise benzyl methacrylate. Ethyl palmitate has been applied to aid the reduction of the carbon tetrachloride content of solutions of chlorinated polyisoprene, when this is removed from the polymer by steam or hot water.

Details

Pigment & Resin Technology, vol. 21 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 14 March 2016

Sherazede Bouderbala and Malika Bouchenak

– The purpose of this study is to compare the effect of olive or salmon oil on the hepatic storage and transport of fatty acids by very-low-density lipoproteins (VLDL).

Abstract

Purpose

The purpose of this study is to compare the effect of olive or salmon oil on the hepatic storage and transport of fatty acids by very-low-density lipoproteins (VLDL).

Design/methodology/approach

In all, 24 male Wistar rats (80 ± 5 g) were fed a 0.5 per cent cholesterol-enriched diet with either 20 per cent casein (C) or chickpea (CP) proteins with 10 per cent olive (O) or salmon (S) oil for 28 days.

Findings

In VLDL-triacyglycerols fatty acids, oleic acid content was higher in CPS as compared to that in CS or CPO and lower in CS and CPO than that in CO; linoleic acid content was higher in all groups; arachidonic acid content was higher in CS and CPO as compared to that in CO. In the liver, TG fatty acids content was lower in CPO or CPS as compared to that in CO or CS; oleic and arachidonic acid contents were lower in CPS than that in CPO; linoleic acid content was lower in CS, CPS and CPO than that in CO, CPO and CO. In liver, phospholipid fatty acid, oleic and arachidonic acid contents were lower in CPS than that in CS; oleic, linoleic and arachidonic acid contents were lower in CPO compared to that in CO. In liver, cholesteryl esters fatty acids, oleic, linoleic and arachidonic acids contents were higher in CPS as compared to that in CS; oleic, linoleic and arachidonic acid contents were lower in CS as compared to that in CO; linoleic and arachidonic acid contents were lower in CPS than that in CPO.

Originality/value

A cholesterol-enriched diet containing casein or chickpea proteins combined with olive or salmon oil affects the hepatic storage and transport of polyunsaturated and monounsaturated fatty acids by VLDL.

Details

Nutrition & Food Science, vol. 46 no. 2
Type: Research Article
ISSN: 0034-6659

Keywords

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