Viscosities of Ammonium Sulfate, Potassium Sulfate, and Aluminum Sulfate in Water and Water +N,N-Dimethylformamide Mixtures at Different Temperatures

2008 ◽  
Vol 53 (10) ◽  
pp. 2469-2472 ◽  
Author(s):  
Pandharinath S. Nikam ◽  
Jayraj S. Aher ◽  
Sanjeevan J. Kharat
Keyword(s):  
Ammonium Sulfate ◽  
Aluminum Sulfate ◽  
Potassium Sulfate ◽  
Different Temperatures

Study of the Hydration Process of Synthetic Preparation of Ettringite by Direct Addition of Aluminum Sulfate and Calcium Hydroxide

2018 ◽  
Vol 276 ◽  
pp. 60-65
Author(s):  
Marcela Fridrichová ◽  
Dominik Gazdič ◽  
Jana Mokrá ◽  
Karel Dvořák
Keyword(s):  
Calcium Hydroxide ◽  
Aluminum Sulfate ◽  
Xrd Analysis ◽  
Standard Laboratory ◽  
X Ray Diffraction ◽  
X Ray ◽  
Saturated Water ◽  
Direct Addition ◽  
Different Temperatures ◽  
The Stability

The stability of ettringite as high-watery mineral is highly dependent on the ambient temperature. Under standard laboratory conditions, onset of decomposition of this phase occurs at temperature of 80°C already and the theoretical temperature of the complete decomposition of ettringite is 180°C. Ettringite decomposition can occur at significantly different temperatures under humidity conditions other than the laboratory ones. Within the work verification of the possibility of synthetic preparation of ettringite by direct addition of aluminum sulfate, Al2(SO4)3·18H2O, and calcium hydroxide, Ca (OH)2, as an alternative method to the yeelimite hydration procedure was carried out. The stability of the resulting systems was examined in two different environments, namely in a laboratory environment and the environment of saturated water vapour. The phase composition of the samples was determined by X-ray diffraction (XRD) analysis, thermal analysis and scanning electron microscopy (SEM).

Isolation of Grifolan Synthase (GS) and its Partly Enzymatic Properties

2011 ◽  
Vol 396-398 ◽  
pp. 1446-1453 ◽  
Author(s):  
Wei Guo Wang ◽  
Peng Li ◽  
Yu Jia Cui ◽  
Yong Liang Zhao ◽  
Ya Nan Gu
Keyword(s):  
Enzyme Activity ◽  
Protein Content ◽  
Ammonium Sulfate ◽  
Enzyme Reaction ◽  
Enzymatic Properties ◽  
Crude Enzyme ◽  
Grifola Frondosa ◽  
Isolation Method ◽  
Fermentation Liquor ◽  
Different Temperatures

Abstract: Purpose To search for an isolation method of grifolan synthase, and research grifolan synthase partly enzymatic properties. Methods Taking Grifola frondosa as material, the mycelium was broken by ultrasonic, and then centrifugated, the supernatant was collected, GS was precipitated by different concentrations of ethanol, ammonium sulfate and acetone, the suitable isolation method of GS was researched out by taking enzyme activity and protein content as parameters. Reducing sugar, protein content and total sugar content were determined respectively by using 3,5-dinitrosalicylic acid (DNS) method, Coomassie brilliant blue method and phenol-sulfuric acid method. Taking glucose as substrate, GS activity was reflected by the consumption of glucose. Consumption of glucose was measured by DNS method. The optimal temperature and pH of GS enzyme reaction was determined by carrying out the enzyme assay at different temperatures and pH levels.The acid-base stability of GS was determined by subjecting GS to different pH levels for 60 minutes, and the heat stability of GS was determined by subjecting GS to different temperatures for 30 minutes. The direction of GS enzymatic reaction was determined by measuring the consumption of β-glucan in 1 minute. The possibility of GS existing extracellular was judged by determining GS activity in extracellular fermentation liquor. Results The proper isolation method of GS is that the mycelium was collected from fermentation liquor and broken by ultrasonic for 1min, then centrifugated at 5000rpm for 10 minutes and a supernatant was collected. Ammonium sulfate was added to the concentration of 60%, and then centrifugated at 12000rpm for 10 minutes at 4°C, the pellets was collected as GS crude enzyme. Using this method, 93.86mg of crude enzyme which enzyme activity was 5700U/mg was obtained from 100g mycelium with moisture content of 87.28%, extraction rate of crude enzyme was 0.7379%. The optimum pH of GS enzyme reaction was pH=5.0 and the optimum temperature was 15°C, GS was most stable at pH=5.0 and in the range of 30 °C to 50 °C. Just 0.6996μg β-glucan was hydrolyzed in 1 minute by GS which can actually consume 5700μg glucose per minute in the synthetic reaction of β-glucan, considering the error in actual measurement, it can be considered that GS is a one-way enzyme that it can only catalyze the synthesis of β-glucan. GS activity in extracellular Grifola frondosa fermentation liquor was -0.1875U/ml, indicating that GS is one kind of intracellular enzyme and without GS activity in fermentation liquor or extracellular. Conclusion An isolation method of grifolan synthase form the mycelium of Grifola frondosa was researched out, and grifolan synthase partly enzymatic properties were studied in this paper. It can lay the foundation for the further study on the structure and function of GS and grifolan production.

Hot Corrosion Mechanism of Silicon Nitride Based Ceramics Exposed to Coal Slag Containing Potassium Sulfate

1994 ◽  
Vol 367 ◽  
Author(s):  
Z.B. Yu ◽  
W.H. Li ◽  
N.F. Li
Keyword(s):  
Silicon Nitride ◽  
Silicon Dioxide ◽  
Potassium Salt ◽  
Potassium Sulfate ◽  
Silicate Melt ◽  
Corrosion Mechanism ◽  
Silica Layer ◽  
Before And After ◽  
Different Temperatures ◽  
Coal Slag

AbstractThe corrosion of three kinds of silicon nitride based ceramics by static liquid potassium sulfate-coal slag immersion was investigated at high temperatures. The reaction kinetics between silicon nitride based ceramics and coal-slag-potassium sulfate was investigated, different kinetic curves were obtained at different temperatures, it was l-(l-a)1/3=kt at 1350°C and a=kt2at 1400°C. Phase composition, microstructure of the materials before and after corrosion were studied by XRD, SEM/EDAX, and EPMA etc, which lead to the following detailed corrosion mechanism: (1) oxidation of silicon nitride based ceramics by potassium salt and oxygen in air simultaneously and formation of silicon dioxide. (2) melting of as-formed silica by potassium sulfate or K-contained silicate and resulting in a silicate melt Me-K20-xSiO2, and (3) formation of a protective silica layer below the silicate melt.

The Effect of Concentration of Phosphoric Acid on the Degree of Reduction of VPO Catalyst

2011 ◽  
Vol 335-336 ◽  
pp. 1424-1427
Author(s):  
Yan Lin Zhang ◽  
Yang Zhou ◽  
Dian Hui Hou ◽  
Xi Wu Fan ◽  
Nai Di Tan
Keyword(s):  
Particle Size ◽  
Phosphoric Acid ◽  
Specific Surface ◽  
Ammonium Sulfate ◽  
Ferrous Ammonium Sulfate ◽  
Compact Structure ◽  
Average Valence ◽  
Different Temperatures ◽  
Vpo Catalyst ◽  
Ferrous Ammonium

Making VPO catalyst in the condition of different concentrations of Phosphoric acid and the temperatures，determine the average valence of vanadium. with the method of Potassium permanganate-Ferrous ammonium sulfate, to investigate the effect of different concentration of phosphoric acid on the average valence of catalyst, under the different temperatures. The structure, composition, crystal, and the Particle size has been characterized by XRD and SEM. The results confirmed that compare with higher concentration of phosphoric acid，the catalyst that were made with lower concentration phosphoric acid had the low average valence, greater specific surface area, better crystallinity, and more compact structure.

Potassium sulfate and ammonium sulfate affect quality and quantity of camelina oil grown with different irrigation regimes

2020 ◽  
Vol 148 ◽  
pp. 112308 ◽  
Author(s):  
Neda Amiri-Darban ◽  
Ghorban Nourmohammadi ◽  
Amir Hosein Shirani Rad ◽  
Seyed Mohammad Javad Mirhadi ◽  
Islam Majidi Heravan
Keyword(s):  
Ammonium Sulfate ◽  
Potassium Sulfate ◽  
Camelina Oil ◽  
Irrigation Regimes
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