Effect of Adding Sodium Chloride on Tetra-n-butylammonium Chloride Semiclathrate Thermal Stability at Atmospheric Pressure

2018 ◽  
Vol 64 (1) ◽  
pp. 303-314 ◽  
Author(s):  
Miad Siddiq ◽  
Rodney Wigent
Keyword(s):  
Thermal Stability ◽  
Sodium Chloride ◽  
Atmospheric Pressure

Thermal Behavior of the Gypsum Binder in Dental Casting Investments

1986 ◽  
Vol 65 (6) ◽  
pp. 877-884 ◽  
Author(s):  
T. Mori
Keyword(s):  
Phase Transition ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Sodium Chloride ◽  
Thermal Behavior ◽  
Boric Acid ◽  
Atmospheric Pressure ◽  
Calcium Sulfate ◽  
Calcium Sulfate Dihydrate ◽  
Initial Stage

This study examined the thermal behavior of cast gypsum specimens, with and without additives, by means of simultaneous differential thermal analysis-thermogravimetry (DTA-TG) and dilatometry. Specimens were prepared from wet-calcined hemihydrates (Hydrocal and Den-site). The additives studied were boric acid (H3BO 3) and sodium chloride (NaCl), and these were added to the hemihydrate powders in concentrations of 2 wt% (in the case of H3BO3) and 0.5 wt% (in the case of NaCl). A large shrinkage was observed in the range of 300 to 500°C, and this was greatly reduced when either H3BO3 or NaCl was present. The dehydration of gypsum (calcium sulfate dihydrate) was not completed until the initial stage of this large shrinkage was reached, but the phase transition of calcium sulfate anhydrite (III-CaSO4 to II-CaSO4) was the major cause for the large shrinkage. This phase transition occurred over a much wider temperature range than that suggested by the DTA-TG results. Dehydration conditions similar to those employed in wet calcination of gypsum appeared to be produced under atmospheric pressure when NaCl was present.

scholarly journals Thermal behavior of Pd@SiO2 nanostructures in various gas environments: a combined 3D and in situ TEM approach

Nanoscale ◽  
2018 ◽  
Vol 10 (43) ◽  
pp. 20178-20188 ◽  
Author(s):  
Walid Baaziz ◽  
Mounib Bahri ◽  
Anne Sophie Gay ◽  
Alexandra Chaumonnot ◽  
Denis Uzio ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Thermal Behavior ◽  
Atmospheric Pressure ◽  
Electron Tomography ◽  
Core Shell ◽  
In Situ Tem ◽  
Environmental Tem ◽  
First Time ◽  
Thermal Stability Of

The thermal stability of core–shell Pd@SiO2 was for the first time monitored by using in situ Environmental TEM at atmospheric pressure coupled with Electron Tomography on the same particles.

scholarly journals Thermal Stability of 0.9% Sodium Chloride IV Fluid exposed to Short- and Long-Term Extreme Conditions

2020 ◽  
Author(s):  
Mohammed Akkbik ◽  
Mohamed Izham Mohamed Ibrahim ◽  
Mohammad Diab ◽  
Ayad Moslih ◽  
Ahmed Makhlouf ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Sodium Chloride ◽  
Normal Saline ◽  
Real Life ◽  
Exchange Chromatography ◽  
Effect Of Temperature ◽  
Long Term Study ◽  
Short And Long Term ◽  
Thermal Stability Of

Purpose: 0.9% sodium chloride IV fluid (normal saline) is critical in a clinical setting and may save lives. Data on thermal stability of normal saline, in out-of-hospital settings, are lacking. The purpose of this study was to evaluate the effect of temperature on normal saline stability. Method: Normal saline provided in flexible plastic containers (Qatar Pharma, BA:1929013008, n=96) were stored at constant temperature of 22, 50, or 70°C, and at cyclic temperature of 70°C for 8 hours and 22°C for 16 hours for a period up to 28 days. The containers were sampled at 0, 12, 24, 48 and 72 hours and at 1, 2, 3, and 4 weeks in the short- and long-term study, respectively. Fluid inside containers was evaluated for discoloration, turbidity, bulging, and pH. A 1 mL of normal saline was withdrawn from each container and stored at 4°C until analysis. A 20 µL was diluted in 12 mL distilled water to be injected into ion exchange chromatography instrument (Metrohm, 850 Professional IEC) for the measurement of sodium and chloride levels. Results: Discoloration or turbidity of normal saline fluid was not observed at any temperature or exposure period. The container slightly bulged at 50˚C and largely bulged at 70˚C & cyclic. The pH was 5.59±0.08 at 22˚C, 5.73±0.04 at 50˚C, 5.86±0.02 at 70˚C and 5.79±0.03 at cyclic. Remaining sodium and chloride levels ranged from 100.2±0.26% to 111.27±4.22% and from 99.04±0.76 to 110.95±2.62%, respectively. Conclusion: Normal saline containers are stable up to 4 weeks under simulated constant and cyclic high temperatures. Storage in the cabinet of ambulance vehicles during hot summer season in an arid country like Qatar is to be assessed in real-life conditions.

scholarly journals Refractometric study on binary, ternary, and quaternary solutions made by water, methanol, ethanol, glycerol, D-glucose monohydrate (DGMH), sucrose, and sodium chloride at T = 293.15 K and atmospheric pressure

2019 ◽  
Vol 62 (4) ◽  
Author(s):  
Fardad Koohyar ◽  
Javad Nasiri ◽  
Farhoush Kiani
Keyword(s):  
Refractive Index ◽  
Sodium Chloride ◽  
Atmospheric Pressure ◽  
Empirical Equation ◽  
Refractive Indices ◽  
Glycerol Water ◽  
Binary Solutions ◽  
Wide Range ◽  
Water Glycerol ◽  
Semi Empirical

The glycerol, D-glucose monohydrate (DGMH), sucrose, and sodium chloride are used in food industries and the measurement of properties for these components and their aqueous solutions can be important. In this research work, the refractive indices for binary solutions of (methanol + glycerol), (ethanol + glycerol), ternary solutions of (water + glycerol + DGMH), (water + glycerol + sucrose), (water + sucrose + DGMH), (water + sucrose + ethanol), (water + ethanol + DGMH), (water + NaCl + DGMH), (water + methanol + NaCl), (water + ethanol + NaCl), (water + NaCl + glycerol), (water + sucrose + NaCl), and quaternary solutions of (water + ethanol + sucrose + DGMH), (water + ethanol + sucrose + glycerol), (water + NaCl + sucrose + glycerol) were measured in wide range of mole fractions at T = 293.15 K and atmospheric pressure. For binary solutions of this study, the changes of refractive index on mixing, ∆nD, were calculated in each mole fraction at T = 293.15 K. Also, the refractive index of binary solutions was fitted by a semi-empirical equation. The constant of this equation, Kr, was represented by Koohyar et al. in 2011. This constant can be used to investigate power of interactions between solute and solvent molecules. For ternary and quaternary solutions of this study, a semi-empirical equation was used to determine refractive indices at given temperature. The comparison between calculated and experimental refractive indices shows that there is a good agreement between them especially in lower molal concentrations.    

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