scholarly journals New Solvent for Polyamide 66 and its use for Preparing Single-Polymer Composite Coated-Fabric

2018 ◽  
Author(s):  
Mostafa Jabbari ◽  
Parviz Rashidi Ranjbar ◽  
mikael skrifvars ◽  
Dan Åkesson ◽  
Mohammad J. Taherzadeh
Keyword(s):  
Calcium Chloride ◽  
Calcium Ion ◽  
Solvent System ◽  
Polyamide 66 ◽  
Coated Fabric ◽  
Ph Decrease ◽  
The One ◽  
Engineering Polymers ◽  
Water Gas ◽  
Gas Tightness

Polyamides (PAs) are one of the most important engineering polymers; however, the difficulty in dissolving them hinders their applications. Formic acid (FA) is the most common solvent for PAs, but it has industrial limitations. In this contribution, we proposed a new solvent system for PAs by replacing a portion of the FA with urea and calcium chloride (FAUCa). Urea imparts the hydrogen bonding and calcium ion from the calcium chloride, as a Lewis acid was added to the system to compensate for the pH decrease due to the addition of urea. The results showed that the proposed solvent (FAUCa) could readily dissolve PAs, resulting in less decrease in the mechanical properties during the dissolution. The composite prepared using the FAUCa has almost the same properties like the one prepared using the FA solution. The solution was applied on a polyamide 66 fabric to make an all-polyamide composite coated-fabric, which then was characterized. The FAUCa solution had a higher viscosity than the one prepared using the neat FA solvent, which can be an advantage in the applications which needs higher viscosity like preparing the all-polyamide composite coated-fabric. A more viscouse solution makes a denser coating which will increase the water-/gas-tightness. In conclusion, using the FAUCa solvent has two merits: 1. replacement of 40 % of the FA with less harmful and environmentally-friendly chemicals and 2. enabling for the preparation of more viscouse solutions, which makes denser coating.

scholarly journals New Solvent for Polyamide 66 and Its Use for Preparing a Single-Polymer Composite-Coated Fabric

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Mostafa Jabbari ◽  
Mikael Skrifvars ◽  
Dan Åkesson ◽  
Mohammad J. Taherzadeh
Keyword(s):  
Calcium Chloride ◽  
Solvent System ◽  
Polyamide 66 ◽  
Coated Fabric ◽  
Viscous Solution ◽  
Ph Decrease ◽  
The One ◽  
Engineering Polymers ◽  
Viscous Solutions ◽  
Water Gas

Polyamides (PAs) are one of the most important engineering polymers; however, the difficulty in dissolving them hinders their applications. Formic acid (FA) is the most common solvent for PAs, but it has industrial limitations. In this contribution, we proposed a new solvent system for PAs by replacing a portion of the FA with urea and calcium chloride (FAUCa). Urea imparts the hydrogen bonding and calcium ion from the calcium chloride, as a Lewis acid was added to the system to compensate for the pH decrease due to the addition of urea. The results showed that the proposed solvent (FAUCa) could readily dissolve PAs, resulting in a less decrease in the mechanical properties during the dissolution. The composite prepared using the FAUCa has almost the same properties as the one prepared using the FA solution. The solution was applied on a polyamide 66 fabric to make an all-polyamide composite-coated fabric, which then was characterized. The FAUCa solution had a higher viscosity than the one prepared using the neat FA solvent, which can be an advantage in the applications which need higher viscosity like preparing the all-polyamide composite-coated fabric. A more viscous solution makes a denser coating which will increase the water /gas tightness. In conclusion, using the FAUCa solvent has two merits: (1) replacement of 40% of the FA with less harmful and environmentally friendly chemicals and (2) enabling for the preparation of more viscous solutions, which makes a denser coating.

scholarly journals EXPERIMENTAL STUDIES ON INFLAMMATION

1921 ◽  
Vol 34 (4) ◽  
pp. 375-396 ◽  
Author(s):  
Elizabeth Pauline Wolf
Keyword(s):  
Calcium Chloride ◽  
Calcium Ion ◽  
Sodium Phosphate ◽  
Blood Clot ◽  
Experimental Studies ◽  
Carbon Chain ◽  
Negative Ion ◽  
Depth Of Penetration ◽  
Inorganic Ion

1. Wright's method for the study of chemotaxis of leucocytes in vitro, slightly modified, has been found to be most satisfactory in the estimation of the degree of chemotaxis of various substances, because it is possible to make an exact quantitative determination of the leucocytes that have migrated from the blood clot and adhere to the surfaces containing the tested substance. 2. The calcium ion is the only inorganic ion per se which is found to be positively chemotactic under the conditions of these experiments. It is markedly chemotactic in all concentrations and in all combinations, except the citrate. Here the negative chemotaxis of the citrate ion neutralizes the positive chemotaxis of the calcium ion, and neutrality of chemotactic effect results. 3. The sodium and magnesium ions themselves are neutral. Magnesium and sodium salts are dependent upon the negative ion with which the magnesium or sodium is combined for such positive or negative chemotaxis as is exhibited. All the phosphates of sodium, whether tri-, di-, or monobasic salts, are markedly positively chemotactic, and when combined with other reagents which are themselves neutral or negatively chemotactic, produce marked positive chemotaxis. The blood of a person who has taken phosphates either by mouth or intravenously shows a great increase in chemotaxis with sodium phosphate, with calcium chloride, and even with sodium chloride which is ordinarily neutral. 4. All potassium salts are negatively chemotactic. 5. Many substances act synergistically as regards chemotaxis; e.g., when strontium and magnesium salts are mixed there is a marked increase in chemotaxis. Sodium phosphate acts synergistically with calcium chloride. 6. Mercury salts fix the leucocytes in this method so that their influence on chemotaxis cannot be determined. 7. Morphine and morphine salts are positively chemotactic; this is contrary to the results obtained by others with different methods. 8. Substances which produce a very acute inflammation, such as cantharidin, histamine, or turpentine, are found to be positively chemotactic by this method, but substances, such as mustard gas, which produce a marked necrotizing effect are found to be negatively chemotactic, or neutral, though physiologically they would appear to be positively chemotactic. 9. All amino-acids and amines are positively chemotactic to a certain extent. It seems that the longer the carbon chain, the greater the degree of chemotaxis, though this is not absolute. Tyramine is one exception to this, for it causes a peculiar clumping of the cells, so that it is impossible to count the number adhering, and thus determine whether or not tyramine is positively chemotactic. 10. The time that the blood of animals is examined after eating makes a marked difference in the number of cells adhering, for shortly after eating, within 30 minutes, very many more cells will adhere to the agar than at a later time. 11. The blood of different species of animals reacts differently towards different reagents. The chemical composition of these agents seems to have nothing to do with this difference in reaction as far as we could determine. 12. With frozen serial sections it has been found that the depth of penetration of the leucocytes into the agar is proportional to the positive chemotaxis produced by the substance combined with the agar, as demonstrated by the number of leucocytes adherent to the walls of the test chambers.

Determination of Geographical Origin of Spices. I. Cassia and Cinnamon by Thin Layer Chromatography

1967 ◽  
Vol 50 (4) ◽  
pp. 852-856
Author(s):  
William A Voelker ◽  
Jean N Skarzynski ◽  
William H Stahl
Keyword(s):  
Thin Layer ◽  
Ethyl Acetate ◽  
Geographical Origin ◽  
Raw Materials ◽  
Screening Method ◽  
Solvent System ◽  
Dimensional System ◽  
Quality Control Tool ◽  
Ceylon Cinnamon ◽  
The One

Abstract A thin layer chromatographic method has been devised to differentiate the geographical origin of cinnamons (cassias). For the one-dimensional screening method, benzene-ethyl acetate-glacial acetic acid (90: 10:1, v/v/v), was used as the solvent system. The two-dimensional system first used hexane-acetone (85:15) and then benzene- ethyl acetate (85:15). The following products were differentiated on the basis of fluorescing spots, some spots common to all and some spots unique: Saigon cassia, Batavia cassia, Korintji cassia, Ceylon cinnamon, and Seychelles cinnamon. The technique is primarily designed as a quality control tool to evaluate incoming shipments of raw materials. However, it can he used to determine composition of unknown mixtures of the ground cinnamons. The technique permits judgment within ± 2 0 % of one type in a mixture

Effect of Calcium Chloride on Dyeing Property of Polyamide 66 Based on Reactive Anthraquinone Dyes with Different Structure

2019 ◽  
Vol 20 (10) ◽  
pp. 2140-2145
Author(s):  
Hongjuan Zhang ◽  
Aiqin Gao ◽  
Kongliang Xie ◽  
Aiqin Hou
Keyword(s):  
Calcium Chloride ◽  
Polyamide 66 ◽  
Dyeing Property ◽  
Anthraquinone Dyes

CALCIUM-INDUCED FORMATION OF FIBRINOGEN -- FIBRIN COMPLEXES

1987 ◽  
Author(s):  
M Kaminski ◽  
J McDonagh
Keyword(s):  
Protein Content ◽  
Calcium Chloride ◽  
Total Protein ◽  
Calcium Ion ◽  
Gel Electrophoresis ◽  
Time Dependent ◽  
Cross Linking ◽  
Total Protein Content ◽  
Dependent Manner ◽  
Precipitate Formation

Presence of calcium chloride (8.3 mM) at u = 0.1 enhanced precipitate formation in several different fibrinogen preparations. The precipitate had gel like properties and demonstrated syneresls when disturbed. Precipitation proceeded in the time dependent manner with a plateau after 30 min. The amount of precipitate ranged from 4-24% of total protein content of different preparations. Precipitates did form at u = 0.1 without calcium ion; however, the amount of protein was 3 to 7 fold less than when calcium ion was present.SOS gel electrophoresis of calcium precipitates demonstrated cross-linking of gamma chains. Cross-linking, but not precipitate formation was blocked by parachloromercurie-benzoate (PCMB). The precipitates were redissolved in 2M urea, treated with thrombin, and analyzed for flbrinopeptide content by HLPC. Precipitate formed in absence of calcium ion contained 19% of FPA and 89% of FPB. Precipitates formed in the presence of calcium ion contained 49% of the expected amount of FPA and 98% of expected FPB. The precipitation phenomenon could be reproduced after fibrin monomer-free fibrinogen (prepared by dialysis of calcium supernatants against calcium free buffer) was treated briefly with thrombin.The above finding suggests that calcium ion enhances polymerization of Intact fibrinogen and molecules missing one or two FPA's.

Effects of Tonin on Vascular Smooth Muscle of the Hypertensive Rat and Normal Rabbit

1980 ◽  
Vol 59 (s6) ◽  
pp. 339s-342s ◽  
Author(s):  
R. Garcia ◽  
E. L. Schiffrin ◽  
G. Thibault ◽  
R. Boucher ◽  
J. Genest
Keyword(s):  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Calcium Ion ◽  
Contractile Response ◽  
Control Group ◽  
Hypertensive Rats ◽  
Contralateral Kidney ◽  
Aortic Smooth Muscle ◽  
The One ◽  
Normotensive Control

1. The response of arterial smooth muscle to noradrenaline was studied in one-clip hypertensive rats with or without the contralateral/kidney and in normotensive rabbits. 2. Strips of aorta from one-kidney, one-clip hypertensive animals were less responsive to noradrenaline than normotensive control rats. The contractile response of strips from two-kidney, one-clip hypertensive animals was not different from the control group. These results suggest that the mechanisms responsible for the lesser reactivity in the one-kidney hypertensive group are not a consequence of elevated blood pressure itself, but may be related to the intrinsic contractility of aortic smooth muscle. 3. Tonin potentiated the contraction induced by noradrenaline in aortic strips from hypertensive and normotensive rats. However, this effect was more important in the one-kidney, one-clip hypertensive animals. In the aortic and mesenteric strips from normal rabbits, tonin produced not only potentiation to noradrenaline but direct contraction. 4. The potentiation to noradrenaline and the direct effect of tonin were not affected by a variety of antagonists but were blocked by a calcium ion antagonist, verapamil, suggesting that tonin may act directly on vascular smooth muscle through mechanisms which might be mediated by calcium ions.

Complex-formation between triphosphoinositide and experimental allergic encephalitogenic protein

1969 ◽  
Vol 111 (5) ◽  
pp. 637-646 ◽  
Author(s):  
F. B. Palmer ◽  
R. M. C. Dawson
Keyword(s):  
Sodium Chloride ◽  
Calcium Chloride ◽  
Complex I ◽  
Solvent System ◽  
Constant Composition ◽  
Complex Ii ◽  
Acidic Phospholipids ◽  
Chloroform Methanol ◽  
Experimental Allergic

1. Reactions between triphosphoinositide and the basic experimental allergic encephalitogenic (EAE) protein were examined in aqueous solution and in a biphasic solvent system (chloroform–methanol–water, 8:4:3, by vol.). 2. In the absence of salt an insoluble complex (I) is formed containing triphosphoinositide and EAE protein in proportions that represent complete neutralization of lipid and protein at the pH concerned. 3. In the presence of a low concentration (0·05m) of sodium chloride an insoluble positively charged complex (II) forms. It contains triphosphoinositide and EAE protein in a lower concentration ratio than complex I. This complex, which has a constant composition between pH7·5 and pH10, can take up additional micellar triphosphoinositide producing complex I, which can then be solubilized by excess of triphosphoinositide. 4. The complexes are dissociated by more concentrated sodium chloride solutions and low concentrations of calcium chloride, suggesting that they are largely stabilized by electrostatic bonds. The protein recovered after dissociation is immunologically active and has the same electrophoretic mobility as the original. 5. Water-insoluble ternary complexes containing triphosphoinositide, EAE protein and large amounts of phosphatidylcholine can be prepared. From these, chloroform–methanol (2:1, v/v) extracts only phosphatidylcholine. 6. An insoluble ternary complex of Ca2+ ion, EAE protein and triphosphoinositide can be prepared by adding calcium chloride to a complex I preparation solubilized by excess of triphosphoinositide. 7. EAE protein will also form complexes with other acidic phospholipids, e.g. phosphatidic acid, phosphatidylserine and phosphatidylinositol, but not with phosphatidylcholine or phosphatidylethanolamine. The phosphatidylinositol and phosphatidylserine complexes are chloroform soluble, i.e. proteolipids. 8. The possibility that complexes between EAE protein and acidic phospholipids occur in vivo is discussed. Triphosphoinositide and EAE protein occur in ox brain myelin in approximately the same concentration ratios as they do in complex II, formed at physiological salt concentration and pH.

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