Determination of Solubility Parameters for thep-Xylene Oxidation Products

2011 ◽  
Vol 50 (4) ◽  
pp. 2467-2472 ◽  
Author(s):  
Vishnu Malpani ◽  
Pralhad A. Ganeshpure ◽  
Pradip Munshi
Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3091
Author(s):  
Mohammed Ghazwani ◽  
Prawez Alam ◽  
Mohammed H. Alqarni ◽  
Hasan S. Yusufoglu ◽  
Faiyaz Shakeel

This research deals with the determination of solubility, Hansen solubility parameters, dissolution properties, enthalpy–entropy compensation, and computational modeling of a naturally-derived bioactive compound trans-resveratrol (TRV) in water, methanol, ethanol, n-propanol, n-butanol, propylene glycol (PG), and various PG + water mixtures. The solubility of TRV in six different mono-solvents and various PG + water mixtures was determined at 298.2–318.2 K and 0.1 MPa. The measured experimental solubility values of TRV were regressed using six different computational/theoretical models, including van’t Hoff, Apelblat, Buchowski–Ksiazczak λh, Yalkowsly–Roseman, Jouyban–Acree, and van’t Hoff–Jouyban–Acree models, with average uncertainties of less than 3.0%. The maxima of TRV solubility in mole fraction was obtained in neat PG (2.62 × 10−2) at 318.2 K. However, the minima of TRV solubility in the mole fraction was recorded in neat water (3.12 × 10−6) at 298.2 K. Thermodynamic calculation of TRV dissolution properties suggested an endothermic and entropy-driven dissolution of TRV in all studied mono-solvents and various PG + water mixtures. Solvation behavior evaluation indicated an enthalpy-driven mechanism as the main mechanism for TRV solvation. Based on these data and observations, PG has been chosen as the best mono-solvent for TRV solubilization.


2021 ◽  
Author(s):  
Indira Pérez Bermúdez ◽  
Arletis Cruz Llerena ◽  
Keyla Tortoló Cabañas ◽  
Manuel Díaz de los Ríos ◽  
Miguel Ángel Peña ◽  
...  

Abstract Purpuse: Fodder yeast is obtained in an aerobic fermentation process where foaming is a major problem to be solved. In this article, the antifoam property of crude and purified filter cake oil is evaluated in order to use this residual as an alternative to replace the import of commercial antifoam agents and to reduce the production costs of fodder yeastMethod: Knock down test and the comparisons with two commercial antifoam agents were done. Blackstrap molasses medium at 20 and 40 g/L of total reducing sugar was used. All products were studied in their pure form and commercial ones also in dilutions 1:2 and 1:5 v/v. Hansen's solubility parameters (HSPs) to analyze the affinity of each defoamer for yeast were determined.Results: It was obtained the crude and purified filter cake oil showed similar behavior to commercial defoamers with an immediate antifoam effect, removing between 40 and 60% of the initial foam at both sugar concentrations in the first 5 minutes. The regression model showed purified filter cake oil has the greatest knockdown effect (Ca = 55.85 and 74.32) and with greater foam suppression stability the commercial defoamer Quimifoam Máster (Cb = -0.69 and -1.38). Ra values obtained in HSPs test, indicated the affinity of defoamers to the medium. Conclusion: Purified filter cake oil is an effective product for its use as an antifoam with the best knock down effect for both concentrations of sugars in the medium. The determination of HSPs corroborates the effectiveness of this product to suppress foam.


2021 ◽  
Author(s):  
Shalmali Bapat ◽  
Stefan O. Kilian ◽  
Hartmut Wiggers ◽  
Doris Segets

<p>A thorough understanding of complex interactions within particulate systems is a key for knowledge-based formulations. Hansen solubility parameters (HSP) are widely used to assess the compatibility of the dispersed phase with the continuous phase. At present, the determination of HSP is often based on a liquid ranking list obtained by evaluating a pertinent dispersion parameter using only one pre-selected characterization method. Furthermore, one cannot rule out the possibility of subjective judgment especially for liquids for which it is difficult to decipher the compatibility or underlying interactions. As a result, the end value of HSP might be of little or no information. To overcome these issues, we introduce a generalized technology-agnostic combinatorics-based approach. We discuss the principles of the approach and the implications of evaluating and reporting particle HSP values. We demonstrate the approach by using SiN<sub>x</sub> particles. We leverage the analytical centrifugation data to evaluate stability trajectories of SiN<sub>x</sub> dispersions in various liquids to deduce particle-liquid compatibility. </p>


Author(s):  
Cigdem Kilicarislan Ozkan ◽  
Hasan Ozgunay

Hydrogen peroxide and sodium metaperiodate oxidation of starch and their possible utilization in tanning/retanning were examined in our previous studies. In the present part, accordingly with our previous findings, hydrogen peroxide and sodium metaperiodate oxidation products having appropriate molecular weight/size were selected and additionally carboxymethylated. The yields of the processes (carboxymethyl starches) were characterized comprehensively and the effect of carboxymethylation process on structures and tanning abilities were tried to be identified. The characterization results revealed that the carboxymethyl groups were successfully included into the structure and the water solubility of oxidized starches (especially periodate oxidized ones) increased by carboxymethylation process. From the evaluation of the tanning results and considering its properties i.e. gentle tanning effect with less astringency and correspondingly a relatively soft leather handle and smooth grain, it is concluded that dialdehyde carboxymethyl starch (CMS 1:0.7) can be utilized as yet another good alternative sustainable green tanning/retanning agent from starch.


1966 ◽  
Vol 49 (2) ◽  
pp. 407-412
Author(s):  
Harry Shuman ◽  
Ugo R Cieri

Abstract A method is presented for determining residues of chlorbenside including its sulfoxide and sulfone oxidation products. The method employs the Mills-Onley-Gaither extraction procedure. Chlorbenside and chlorbenside sulfoxide are converted to chlorbenside sulfone by a short oxidation with chromic-acetic acid solution. Chlorbenside sulfone is isolated from interfering pesticides and most oxidation products on an aluminum oxide column and determined by electron capture gas chromatography. Recoveries for mixtures of the three components added to apple samples at 0.3–5 ppm (calculated as chlorbenside) were between 92 and 110%.


Sign in / Sign up

Export Citation Format

Share Document