Adsorption Isotherms of Citric Acid Acting as a Growth-Suppressor onto the (100) and (111) Faces of Sodium Chloride Crystals in Supersaturated Aqueous Solution

2006 ◽  
Vol 29 (2) ◽  
pp. 247-250 ◽  
Author(s):  
S. Sasaki ◽  
N. Kubota ◽  
N. Doki
2021 ◽  
Vol 7 (1) ◽  
pp. 1-9
Author(s):  
Taslima Ayesha Aktar Nasrin ◽  
◽  
Latifa Yasmin ◽  
Most Sadia Arfin ◽  
Mohammad Mainuddin Molla ◽  
...  

Fresh cut carrot (Daucus carota L.) slices were treated with hot (60°C) water and hot aqueous solution (2% sodium chloride, 2% citric acid and 10% lime juice) for 1 min and then surface water was removed. Following treatment, fresh-cut carrot slices were kept in a polypropylene (PP) box and stored in a refrigerator (4±1°C and 50±5% RH) for 12 days. The effectiveness of the treatments in extending shelf life was evaluated by determining respiration rate, firmness, weight loss, external colour, whiteness index (WI), some chemical parameters (ascorbic acid content, TSS, acidity, pH, total sugar, reducing sugar and beta carotene), total bacterial count (TBC) and sensory quality. The highest increment of WI (48.4%) was observed without heat-treated carrot slices. On the other hand, WI was increased by 12.1% and 21.7% in carrot slices treated with hot aqueous solution of 2% citric acid and with hot aqueous solution of 2% sodium chloride respectively at 12 days of storage. On the 12th day of storage, fresh-cut carrot treated with hot aqueous solution of 2% citric acid scored 7.3 and the rest of the sample scored less than 4.5 (indicate as unacceptable) in overall acceptability. Carrot slices treated with hot aqueous solution of 2% citric acid and 2% sodium chloride retained a minimum number of TBC and delayed changes in WI, external colour and beta carotene content compared to without heat-treated carrot slices. Keywords: Citric acid, respiration rate, sensory quality, sodium chloride, total bacterial count, whiteness index


2021 ◽  
pp. 50655
Author(s):  
Aafia Tehrim ◽  
Min Dai ◽  
Xiange Wu ◽  
Malik Muhammad Umair ◽  
Imran Ali ◽  
...  

1960 ◽  
Vol 38 (9) ◽  
pp. 1488-1494 ◽  
Author(s):  
E. J. Bounsall ◽  
W. A. E. McBryde

An analytical method is described for the determination of microgram amounts of silver in galena ores, based on the "reversion" of silver dithizonate. Silver is separated from relatively large amounts of lead by extraction as dithizonate into chloroform from an aqueous 1:99 nitric acid solution. Separation from mercury, which is also extracted under these conditions and would, if present, interfere in the analysis, is achieved by reverting the dithizonate solution with a 5% aqueous sodium chloride solution which is also 0.015 molar in hydrochloric acid. Following dilution of this aqueous solution and adjustment of pH, silver is again extracted into chloroform as the dithizonate, and determined absorptiometrically. Analyses of a number of galena ore samples showed a precision of within 3% for a silver content ranging from 0.03 to 0.4%.Some other methods for isolating silver from these samples, which were tried but found unsatisfactory, are discussed.


1997 ◽  
Vol 26 (1) ◽  
pp. 63-84 ◽  
Author(s):  
Pascale Bénézeth ◽  
Donald A. Palmer ◽  
David J. Wesolowski

2001 ◽  
Vol 1 (1) ◽  
pp. 51-60 ◽  
Author(s):  
J. Joutsensaari ◽  
P. Vaattovaara ◽  
M. Vesterinen ◽  
K. Hämeri ◽  
A. Laaksonen

Abstract. A novel method to characterize the organic composition of aerosol particles has been developed. The method is based on organic vapor interaction with aerosol particles and it has been named an Organic Tandem Differential Mobility Analyzer (OTDMA). The OTDMA method has been tested for inorganic (sodium chloride and ammonium sulfate) and organic (citric acid and adipic acid) particles. Growth curves of the particles have been measured in ethanol vapor and as a comparison in water vapor as a function of saturation ratio. Measurements in water vapor show that sodium chloride and ammonium sulfate as well as citric acid particles grow at water saturation ratios (S) of 0.8 and above, whereas adipic acid particles do not grow at S <  0.96. For sodium chloride and ammonium sulfate particles, a deliquescence point is observed at S = 0.75 and S = 0.79, respectively. Citric acid particles grow monotonously with increasing saturation ratios already at low saturation ratios and no clear deliquescence point is found. For sodium chloride and ammonium sulfate particles, no growth can be seen in ethanol vapor at saturation ratios below 0.93. In contrast, for adipic acid particles, the deliquescence takes place at around S = 0.95 in the ethanol vapor. The recrystallization of adipic acid takes place at S < 0.4. Citric acid particles grow in ethanol vapor similarly as in water vapor; the particles grow monotonously with increasing saturation ratios and no stepwise deliquescence is observed. The results show that the working principles of the OTDMA are operational for single-component aerosols. Furthermore, the results indicate that the OTDMA method may prove useful in determining whether aerosol particles contain organic substances, especially if the OTDMA is operated in parallel with a hygroscopicity TDMA, as the growth of many substances is different in ethanol and water vapors.


InterConf ◽  
2021 ◽  
pp. 970-978
Author(s):  
Z. Nizomov ◽  
M. Asozoda ◽  
A. Olimi ◽  
A. Karimzoda

The absorption of ultrasonic waves in the frequency range from 6 to 146 MHz in aqueous solutions of sodium acetate, sodium chloride and calcium has been studied. It was found that only in solutions of calcium cations and acetate anion present simultaneously, relaxation absorption of ultrasonic waves is observed. The experimental data obtained indicate that the observed relaxation absorption of ultrasound in the studied frequency range by an aqueous solution of calcium acetate is associated with the interaction of the acetate anion with the calcium cation in the solution.


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