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Author(s):  
Prabal Boral ◽  
Atul K. Varma ◽  
Sudip Maity

AbstractFour coal samples from Jharia basin, India are treated with nitric acid in glacial acetic acid and aqueous media to find out the chemical, petrographic and spatial structure of the organic mass by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques. X-ray parameters of coal like interlayer spacing (d002), crystallite size (Lc), aroamticity (fa), average number of aromatic layers (Nc), and coal rank (I26/I20) have been determined using profile-fitting software. Considerable variation is observed in treated coals in comparison to the demineralized coals. The d002 values of treated coals have increased in both the media showing increase in disordering of organic moieties. A linear relationship has been observed between d002 values with the volatile matter of the coals. Similarly, the d002 values show linear relationship with Cdmf contents for demineralized as well as for the treated coals in both the media. The Lc and Nc values have decreased in treated coals corresponding to demineralized coals. The present study shows that nitration in both the media is capable of removing the aliphatic side chains from the coals and aromaticity (fa) increases with increase in rank and shows a linear relationship with the vitrinite reflectance. The corresponding I26/I20 values are least for treated coals in glacial acetic acid medium followed by raw and then to treated coals in aqueous medium. FTIR studies show that coal arenes of the raw coals are converted into nitro-arenes in structurally modified coals (SMCs) in both the media, the corresponding bands at 1550–1490 and 1355–1315 cm−1 respectively. FTIR study confirms that nitration is the predominant phenomenon, though, oxidation and nitration phenomena takes place simultaneously during treatment with nitric acid to form SMCs. In comparison to raw coals, the SMCs show higher aromaticity and may be easily converted to coal derived products like activated carbon and specialty carbon materials.


Author(s):  
Yulia Yu. Miroshnichenko ◽  
Anna G. Yarkova ◽  
Irina A. Perederina ◽  
Elena N. Tveryakova ◽  
Galina A. Zholobova

Inorganic nitrile halides have been studied theoretically by quantum-chemical approach and experimentally in the reactions of halogenation, nitration and nitro halogenation of aromatic compounds and alkynes. The generation of nitrile halides was eventually proved can be can be carried out using the iodine system (alkali metal halides) in the presence of alkali metal nitrates in an acetic acid medium. It has been found that the reaction can give the products of iodination, nitration, nitro halogenation, as well as products of cyclization, and oxidation depending on the nature of the halogen. To predict the products of reaction theoretical quantum-chemical calculations for intermediate particles – nitrile halides using the standard Gaussian‑03 software package were carried out. The possibility of NO2Hal formation was approved from quantum calculations. Furthermore the geometry of NO2Hal particles and mechanism of their homo- or heterolytic decay were represented


Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 277
Author(s):  
Peitong Liu ◽  
Violeta Ivanova-Petropulos ◽  
Changqing Duan ◽  
Guoliang Yan

The small changes in concentration of unsaturated fatty acids (UFAs) cause a significant influence on the aromatic component of wines. In this work, the effect of UFAs mixture (including linoleic, oleic, and α-linolenic acids) addition on intra-metabolites and aromatic compounds of two Saccharomyces cerevisiae strain EC1118 and BDX were investigated in red wine fermentation, respectively. The results showed that the pre-fermentative addition of UFAs significantly modified the physiological and energetic state of cells, and affected the levels of intra-metabolites in glycolysis pathway and TCA cycle, redox balance, ATP pool, fatty acids, and amino acids metabolism, which consequently altered the chemical and volatile composition of the wines. Different with the control wine, the wines produced by UFAs addition were characterized with higher amounts of glycerol, C6-alcohols and higher alcohols, and lower levels of acetic acid, medium-chain fatty acids, and acetate esters. Interestingly, the production of ethyl esters showed opposite profiles in different strains due to the distinct expression of EEB1, indicating that the effect of UFAs on ethyl esters syntheses is strain-specificity. Our results highlighted the effectiveness of modulating UFAs content in shaping aroma characteristics, and verified that fine adjusting the content of UFAs combined with inoculating proper yeast is a promising strategy to modulate the aromatic quality of wine, which probably provides an alternative approach to meet the expectations of wine consumers for diverse aromatic qualities.


2021 ◽  
Author(s):  
Prabal Boral ◽  
Atul K. Varma ◽  
Sudip Maity

Abstract Four coal samples from Jharia basin, India are treated with nitric acid in glacial acetic acid and aqueous media to find out the chemical, petrographic and spatial structure of the organic mass by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques.X-ray parameters of coal like interlayer spacing (d002), crystallite size (Lc), aroamticity (fa), average number of aromatic layers (Nc), and coal rank (I26/I20) have been determined using profile-fitting software. Considerable variation is observed in treated coals in comparison to the demineralized coals. The d002 values of treated coals have increased in both the media showing increase in disordering of organic moieties. A linear relationship has been observed between d002 values with the volatile matter of the coals. Similarly, the d002 values show linear relationship with Cdmf contents for demineralized as well as for the treated coals in both the media. The Lc and Nc values have decreased in treated coals corresponding to demineralized coals. The present study shows that nitration in both the media is capable of removing the aliphatic side chains from the coals and aromaticity (fa) increases with increase in rank and shows a linear relationship with the vitrinite reflectance. The corresponding I26/I20 values are least for treated coals in glacial acetic acid medium followed by raw and then to treated coals in aqueous medium.FTIR studies show that coal arenes of the raw coals are converted into nitro-arenes in structurally modified coals (SMCs) in both the media, the corresponding bands at 1550 – 1490 cm-1 and 1355 – 1315 cm-1 respectively. FTIR study confirms that nitration is the predominant phenomenon, though, oxidation and nitration phenomena takes place simultaneously during treatment with nitric acid to form SMCs. In comparison to raw coals, the SMCs show higher aromaticity and may be easily converted to coal derived products like activated carbon and specialty carbon materials.


Author(s):  
Richard Macedo de Oliveira ◽  
Daniel Borges ◽  
Patricia Grinberg ◽  
Zoltan Mester ◽  
Ralph E Sturgeon

Significant enhancements in the photochemical vapor generation (PVG) efficiencies of both Br- and BrO3- species from a 2 % acetic acid medium occur in the presence of 10 mg L-1...


Foods ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1599
Author(s):  
Anika Singh ◽  
Yixin Gu ◽  
Simone D. Castellarin ◽  
David D. Kitts ◽  
Anubhav Pratap-Singh

This work focused on the development of starch-based (potato, corn, sweet potato, green bean and tapioca) edible packaging film incorporated with blueberry pomace powder (BPP). The optical, mechanical, thermal, and physicochemical properties were subsequently tested. The film color was not affected by the addition of BPP. BPP incorporated into corn and green bean starch films showed increased light barrier properties, indicating a beneficial effect to prevent UV radiation-induced food deterioration. Film thickness and transparency were not primarily affected by changing the starch type or the BPP concentration, although the corn starch films were the most transparent. Furthermore, all films maintained structural integrity and had a high tensile strength. The water vapor transmission rate of all the films was found to be greater than conventional polyethylene films. The average solubility of all the films made from different starch types was between 24 and 37%, which indicates the usability of these films for packaging, specifically for low to intermediate moisture foods. There were no statistical differences in Differential Scanning Calorimetry parameters with changes in the starch type and pomace levels. Migration assays showed a greater release of the active compounds from BPP into acetic acid medium (aqueous food simulant) than ethanol medium (fatty food simulant). The incorporation of BPP into starch-chitosan films resulted in the improvement of film performance, thereby suggesting the potential for applying BPP into starch-based films for active packaging.


2020 ◽  
Vol 44 (5) ◽  
pp. 1386-1394
Author(s):  
Gollapudi RAVI KUMAR ◽  
Chandra Rao DASIREDDY ◽  
Ravi VARALA ◽  
Vijay KOTRA ◽  
Hari Babu BOLLIKOLLA

A series of nine methyl sulphones (3a–3i) starting from the aldehydes (1a–1i) were synthesized in two consecutive steps. In the first step, preparation of allyl alcohols (2a–2i) from their corresponding aldehydes by the reaction of sodium borohydride in methanol at room temperature is reported. Finally, methyl sulphones are synthesized by condensing sodium methyl sulfinates with allyl alcohols in the presence of BF3.Et2O in acetic acid medium at room temperature for about 2–3 h. The reaction conditions are simple, yields are high (85%–95%), and the products were obtained with good purity. All the synthesized compounds were characterized by their 1H, 13C NMR, and mass spectral analysis. All the title compounds were screened for antimicrobial activity. Among the compounds tested, the compound 3f has inhibited both Gram positive and Gram negative bacteria effectively and compound 3i has shown potent antifungal activity. These promising components may help to develop more potent drugs in the near future for the treatment of bacterial and fungal infections.


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