Effect of Microstructure and Composition of Limestone, Marble, Basalt, and Quartzite Aggregate on Concrete Durability in Presence of Solutions of Calcium Chloride and Magnesium Sulfate

2009 ◽  
pp. 605-605-12 ◽  
Author(s):  
JE Gillott
Keyword(s):  
Magnesium Sulfate ◽  
Calcium Chloride ◽  
Concrete Durability ◽  
Effect Of Microstructure

The Influence of Agglomerators on Powdering of Chloroprene Rubber PCR-244

2015 ◽  
Vol 1119 ◽  
pp. 334-337
Author(s):  
Xu Ling Wei ◽  
Yu Li Wei ◽  
Guang Bi Gong ◽  
Tao Liang ◽  
Wen Jing Cai ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Potassium Chloride ◽  
Magnesium Sulfate ◽  
Calcium Chloride ◽  
Aluminum Chloride ◽  
Adhesive Material ◽  
Monovalent Salt ◽  
Chloroprene Rubber ◽  
Direct Condensation

Powdered polychloroprene rubber (PCR-244) was prepared by the direct condensation, and the influence of agglomerator kinds and dosages on powdering of PCR-244 were investigated, including trivalent salt (aluminum chloride), divalent salt (magnesium sulfate, calcium chloride) and monovalent salt (sodium chloride, potassium chloride). The result showed that powder chloroprene rubber could be used as adhesive material that calcium chloride was used as agglomerator.

Durability of concrete containing chloride-based accelerating admixtures

1990 ◽  
Vol 17 (1) ◽  
pp. 102-112
Author(s):  
T. Rezansoff ◽  
D. Stott
Keyword(s):  
Calcium Chloride ◽  
Dynamic Modulus ◽  
Linseed Oil ◽  
Standard Test ◽  
Test Method ◽  
Concrete Durability ◽  
Freezing And Thawing ◽  
Cement Ratio ◽  
Freeze Thaw ◽  
Water To Cement Ratio

The influence of CaCl2 or a chloride-based accelerating admixture on the freeze–thaw resistance of concrete was evaluated. Three air entrained mix designs were investigated using ASTM C666-84, Standard Test Method for Resistance of Concrete to Rapid Freezing and Thawing. All mix designs were similar, using cement contents of 340–357 kg/m3 of concrete, except for the addition of either 2% calcium chloride or 2% High Early Pozzolith, while no accelerating admixture was added to the control mix. The entire test program was repeated four times with water-to-cement ratio of 0.46 and three times with the ratio of 0.43. For the Pozzolith-accelerated concrete, half the samples were coated with boiled linseed oil in all seven series. For the control (unaccelerated) concrete, half the samples were coated with boiled linseed oil in one series for each water-to-cement ratio. Performance was monitored using the dynamic modulus of elasticity as obtained from transverse resonant frequency measurements. Weight loss of the specimens was also measured. Only the control samples (no accelerators) showed sufficient durability to satisfy the standard of maintaining at least 60% of the original dynamic modulus after 300 cycles of alternate freezing and thawing. Sealing with linseed oil showed inconsistent improvement in the durability in the various test series when defined in terms of the dynamic modulus; however, weight losses were the lowest of all categories and surface scaling was minimal. Key words: concrete, durability, freeze–thaw testing, calcium chloride, admixtures, sealants, air void system.

scholarly journals Catalytic Biomineralization of Fluorescent Calcite by the Thermophilic Bacterium Geobacillus thermoglucosidasius

2010 ◽  
Vol 76 (21) ◽  
pp. 7322-7327 ◽  
Author(s):  
Naoto Yoshida ◽  
Eiji Higashimura ◽  
Yuichi Saeki
Keyword(s):  
Calcium Carbonate ◽  
Fluorescence Microscopy ◽  
Magnesium Sulfate ◽  
Calcium Chloride ◽  
Sodium Acetate ◽  
Thermophilic Bacterium ◽  
X Ray Diffraction ◽  
X Ray ◽  
Magnesium Calcite ◽  
Hexagonal Crystals

ABSTRACT The thermophilic Geobacillus bacterium catalyzed the formation of 100-μm hexagonal crystals at 60°C in a hydrogel containing sodium acetate, calcium chloride, and magnesium sulfate. Under fluorescence microscopy, crystals fluoresced upon excitation at 365 ± 5, 480 ± 20, or 545 ± 15 nm. X-ray diffraction indicated that the crystals were magnesium-calcite in calcite-type calcium carbonate.

scholarly journals STUDIES IN EXPERIMENTAL EXTRACORPOREAL THROMBOSIS

1927 ◽  
Vol 46 (6) ◽  
pp. 963-977 ◽  
Author(s):  
Takuji Shionoya
Keyword(s):  
Sodium Chloride ◽  
Magnesium Sulfate ◽  
Calcium Chloride ◽  
Bile Salts ◽  
Chloride Solution ◽  
Sodium Chloride Solution ◽  
Thrombus Formation ◽  
Cent Solution ◽  
Venous Cannula ◽  
The Masses

1. Distilled water dialyzes through the collodion tube and causes hemolysis. Clotting of the hemolyzed blood in the collodion tube occurs later. 2. Bile salts accelerate the appearance and development of white thrombi in the heparinized animal. The masses of white thrombi are very loose, soft, fragile and easily broken into clumps of platelets. They are poor in fibrin or the fibrin is abnormal, since they have less retractility than those obtained from the use of physiologic sodium chloride solution or calcium chloride or serum. Despite the increase in number and size of white thrombi, normal clotting does not occur. 3. When the collodion tube is surrounded by 1 or 2 per cent d-glucose solution, tiny and numerous white thrombi appear as radiating figures. The masses of white thrombi are rather loose and fragile. The clotting time of the heparinized blood does not appear to be shortened. 4. When a 1 to 2 per cent solution of calcium chloride is used as the dialyzing fluid outside the collodion tube, or when it is injected into the circulation, the formation of white thrombi is accelerated. They grow very rapidly. In spite of the action of heparin, the white thrombi formed are not so fragile as when bile salts are placed outside of the collodion tube. Fibrin seems to form easily. Obstruction of venous cannula takes place speedily and if the clots in the cannula are not removed, the white thrombi in the collodion tube remain small and become red by sedimentation of red cells. 5. Intravenous use of 10 per cent solution of magnesium sulfate without heparin retards the coagulation of circulating blood and permits the blood to flow through the extracorporeal loop from three to four times as long as normal. The formation of white thrombi, as well as red, is retarded. Magnesium sulfate (1 per cent) in physiologic sodium chloride solution placed outside the collodion tube markedly retards the formation of white and red thrombi in the heparinized animal. Magnesium sulfate (10 per cent), 50 mg. for each kilo of body weight each hour, administered intravascularly in the heparinized animal definitely prevents the first stages of thrombosis, and consequently prevents clotting. 6. It is possible by the combined use of adequate amounts of magnesium sulfate and of heparin intravenously to prevent all stages of thrombus formation for from 1 to 3 hours.

Characterization of Salt Hydrates for Compact Seasonal Thermochemical Storage

2009 ◽  
Author(s):  
V. M. van Essen ◽  
J. Cot Gores ◽  
L. P. J. Bleijendaal ◽  
H. A. Zondag ◽  
R. Schuitema ◽  
...  
Keyword(s):  
Magnesium Sulfate ◽  
Calcium Chloride ◽  
Atmospheric Pressure ◽  
Magnesium Chloride ◽  
Aluminum Sulfate ◽  
Heat Storage ◽  
Water Vapor Transport ◽  
Salt Hydrates ◽  
Seasonal Heat

This paper describes the characterization of four salt hydrates as potential thermochemical material for compact seasonal heat storage in the built environment. First, magnesium sulfate was investigated in detail using TG-DSC apparatus. The results of this study revealed that magnesium sulfate is able to store almost 10 times more energy than water of the same volume. However, the material was unable to take up water (and release heat) under practical conditions. A new theoretical study identified three salt hydrates besides magnesium sulfate as promising materials for compact seasonal heat storage: aluminum sulfate, magnesium chloride and calcium chloride. These salt hydrates (including magnesium sulfate) were tested in a newly constructed experimental setup. Based on the observed temperature lift under practical conditions, it was found that magnesium chloride was the most promising material of the four tested salt hydrates. However, both calcium chloride and magnesium chloride tend to form a gel-like material due to melting or formation of a solution. This effect is undesired since it reduces the ability of the material to take up water again. Finally, it was observed that performing the hydration at low-pressure will improve the water vapor transport in comparison to atmospheric pressure hydration.

Desulfurization Gypsum Whisker Preparation and Performance Study

2014 ◽  
Vol 711 ◽  
pp. 197-200
Author(s):  
Peng Fu ◽  
Guo Zhong Li
Keyword(s):  
Magnesium Sulfate ◽  
Calcium Chloride ◽  
Raw Material ◽  
Performance Study ◽  
Average Ratio ◽  
Maximum Value ◽  
And Performance

Using the desulfurization gypsum as raw material and the atmospheric acidification method, prepared desulfurization gypsum whisker, Studied water gypsum ratio, crystallization agent on properties of gypsum whiskers. Researchs show that, when the water gypsum ratio is 57.14%, the average ratio of length to diameter reaches the maximum value is 41.1; when using calcium chloride and Magnesium sulfate (the quality of various additives in the desulfurization gypsum quality accounted for 2%), the best effect, the ratio of length to diameter is 42.9.

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