Ethanol Acid Research Articles

A post-synthesis modification method of molecular sieve 13X for enriching hopanoids in petroleum

In this study, alkali/acid treatment and ion exchange post-synthesis modification methods to modify the pore diameter and structure of molecular sieve 13X (MS13X) were applied to obtain products, which could then be implemented to improve the enrichment recovery of hopanoids in petroleum. The modification products were analyzed by SEM with EDS, XRD and nitrogen physisorption. The results indicated that the product which had been prepared in the oxalic acid ethanol solution formed some mesopores, and also retained the initial framework of crystal. It was revealed that this product was able to remarkably increase the recovery rate of hopanoids in petroleum without leading to a significant isotope fractionation phenomenon. It is thus shown that this modification method of non-aqueous oxalic acid solution for MS13X can be used as an effective pretreatment tool in the application of compound-specific isotope analysis of hopanes with low concentration.

Comparison of visible and IR transparency of MgO and in situ synthesized LiF decorated on MgO nanoparticles consolidated by spark plasma sintering

In this study, infrared (IR) and visible transparent MgO ceramics were obtained by spark plasma sintering of in-situ synthesized of LiF decorated MgO nanoparticles (MgO–LiF nanocomposite). Lithium acetate (LiAC), trifluoroacetic acid (TFA), oleic acid (OA), and absolute ethanol were used as in-situ synthesis of the LiF phase covered on MgO nanoparticles. TFA/Li (AC) mole ratio, pH, and calcination temperature were changed to obtain the MgO–LiF nanocomposite. The results revealed that with Li (AC)/TFA = 1.5:0.5 and pH = 6 at the calcination temperature of 700 °C, in situ MgO–LiF nanocomposites were well prepared. The SPSed MgO covered with a 0.5% LiF sample showed 30% more visible and IR transmittance than pure MgO bodies sintered at 1100 °C for 10 min.

Physicochemical and structural characteristics of sorghum starch as affected by acid‐ethanol hydrolysis

Acid alcohol hydrolysis of starch is a sustainable chemical method and versatile tool to control molecular weight. Sorghum starch was acid hydrolyzed in ethanol for durations ranging from 24 to 240 h. The native and acid ethanol treated (AET) starches were investigated for their physicochemical, thermal, structural and pasting characteristics. Native starch showed degree of polymerization of 2624 anhydrous glucose units (AGU), amylose content of 26%, swelling power and solubility of 12.2 g/g and 5%, respectively. AET starches showed significantly (p < 0.05) higher solubility (19.8–58.4%) whereas lower values for swelling power (4.3–11 g/g), were observed. The chain length profiles of debranched native and AET sorghum starches, as obtained from high-performance size-exclusion chromatography (HPSEC), indicated preferential degradation of amylose and amylopectin long chains. This led to decrease in intrinsic and pasting viscosities for AET starches. Comparison of X-ray diffractograms (XRD) of native and AET treated sorghum starches showed that there is no change in the diffraction pattern (‘A’ type) upon treatment however the relative crystallinity was observed to decrease upon hydrolysis. Granule structure remained intact however, with AET birefringence loss in some granules was observed, which indicated change in radial orientation of double helices and chain mobility at granule centre. The results indicated that sorghum starch can be tailored by AET and could be used in the food industry for various food formulations.

A facile synthesis of brown anatase TiO2 rich in oxygen vacancies and its visible light photocatalytic property

In this report, we present a facile approach for the synthesis of a brown TiO2 material rich in oxygen vacancies under atmospheric conditions with titanium tetrachloride, oxalic acid and anhydrous ethanol as raw materials. The samples were characterized by X-ray diffraction (XRD), UV–vis diffuse reflectance (UV–vis DRS), Electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), Scanning electron microscope (SEM), High resolution transmission electron microscope (HRTEM), Fourier transform infrared (FTIR) and Raman. The visible light photocatalytic activity of the samples was evaluated by degrading of methylene blue solution. XRD and Raman results showed that the brown TiO2 was anatase TiO2. XPS and EPR indicated the presence of abundant oxygen vacancies in the brown TiO2. UV–vis DRS illustrated that the brown TiO2 had a strong absorption in the visible light region. The photocatalytic activity measurement indicated that the visible light photocatalytic performance of the brown TiO2 was excellent. The surface oxygen vacancies played a key role for the significant enhancement of the brown TiO2 photocatalytic performance.

Sustainability Assessment of Public Transport, Part II—Applying a Multi-Criteria Assessment Method to Compare Different Bus Technologies

Many Swedish regional transport authorities want bus fleets driven on renewable fuels. However, it may be difficult to know what technology, or combination of technologies, to choose. There is a need for improved knowledge and supportive methods for sustainability assessments that can support public procurement processes. In the companion article (Part I), a multi-criteria assessment (MCA) method for assessments of public bus technologies’ sustainability was established, consisting of four key areas and 12 indicators. In this article, the purpose is to apply the method established in part I on different bus technologies by looking at a general Swedish case and assessing buses driven on diesel, Hydrotreated Vegetable Oil (HVO), Fatty Acid Methyl Ester (FAME), ethanol, natural gas, biomethane and electricity. Each technology is assessed on a scale from Very Poor to Very Good according to the indicators: technical maturity, daily operational availability, total cost of ownership, need for investments in infrastructure, cost stability, non-renewable primary energy efficiency, greenhouse gas emission savings, air pollution, noise, local/regional impact on land and aquatic environments, energy security and sociotechnical systems services. The results show the strengths and weaknesses of each technology, which are later discussed. We also critically reflect upon the usefulness and accuracy of the MCA method.

A solvent-responsive robust superwetting titanium dioxide-based metal rubber for oil-water separation and dye degradation

The sewage treatment technology of oil-water separation based on superwetting materials has been widely employed. However, the stability of substrates was rarely considered in the past few years, which greatly limited the application of superwetting materials in engineering field. As a new robust, three-dimensional porous material, metal rubber (MR) has attracted significant attention for solving this problem. To treat the wastewater containing insoluble heavy/light oil and soluble dyes, herein, MR capable of degrading organic dyes with switchable wettability and high oil-water separation efficiency was prepared. Firstly, the superhydrophilic MR was obtained by anodizing. Then, the wettability of MR surface was reversibly switched between superhydrophilic and superhydrophobic via alternate immersion in stearic acid ethanol solution and tetrahydrofuran (THF) solvent to achieve switchable oil-water separation of MR. The superwetting MR displayed excellent abrasion resistance and retained outstanding oil-water separation performance after 100 times of sandpaper abrasion. Besides, the surface of pure titanium MR was rich in titanium dioxide (TiO2) after anodic oxidation, which could effectively degrade the organic dyes under ultraviolet light. Therefore, the as-prepared superwetting MR possesses the ability to treat complex wastewater and have applications prospects in controllable oil-water separation and self-cleaning surfaces.

Genotype- and tissue-specific metabolic networks and hub genes involved in water-induced distinct sweet cherry fruit cracking phenotypes

Sweet cherry fruit cracking is a complex physiological disorder that causes significant economic losses. Despite many years of research there is a lack of understanding of the mechanisms involved in cracking. Here, skin and flesh tissue from the cracking susceptible 'Early Bigi’ and the cracking tolerant ‘Regina’ cultivars were sampled prior and just after water dipping treatment to identify water-affected metabolic networks that putatively involved in fruit cracking. Primary metabolites, most strongly those involved in sugars and amino acid metabolism, such as glucose and asparagine, shifted in 'Early Bigi’ compared with ‘Regina’ tissues following water exposure. Comparisons between cultivars, tissues and dipping points identified significant differentially expressed genes. Particularly, genes related to abscisic acid, ethylene biosynthesis, pectin metabolism, expansins and aquaporins were altered in water-exposed tissues. To further characterize the role of these genes in cracking, their single nucleotide variants of the coding regions was studied in another eight sweet cherry cultivars, which differ in their sensitivity to cracking, revealing a strong link mainly between pectin metabolism-related genes and cracking-phenotypes. Integrated metabolomic and transcriptomic profiling uncovered genotypic- and tissue-specific metabolic pathways, including tricarboxylic acid cycle, cell enlargement, lipid and ethanol biosynthesis, and plant defense that putatively are involved in fruit cracking. Based on these results, a model which describes the skin and flesh metabolic reprogramming during water-induced fruit cracking in the susceptible 'Early Bigi’ cultivar is presented. Τhis study can help to explore novel candidate genes and metabolic pathways for cracking tolerance in sweet cherry.

The anaerobic survival mechanism of Schizophyllum commune 20R-7-F01, isolated from deep sediment 2 km below the seafloor.

Fungi dominated the eukaryotic group in the anaerobic sedimentary environment below the ocean floor where they play an essential ecological role. However, the adaptive mechanism of fungi to these anaerobic environments is still unclear. Here, we reported the anaerobic adaptive mechanism of Schizophyllum commune 20R-7-F01, isolated from deep coal-bearing sediment down to ~2 km below the seafloor, through biochemical, metabolomic and transcriptome analyses. The fungus grows well, but the morphology changes obviously and the fruit body develops incompletely under complete hypoxia. Compared with aerobic conditions, the fungus has enhanced branched-chain amino acid biosynthesis and ethanol fermentation under anaerobic conditions, and genes related to these metabolisms have been significantly up-regulated. Additionally, the fungus shows novel strategies for synthesizing ethanol by utilizing both glycolysis and ethanol fermentation pathways. These findings suggest that the subseafloor fungi may adopt multiple mechanisms to cope with lack of oxygen.

Incorporation of Plasticizers and Co-proteins in Zein Electrospun Fibers.

As a means to alter the physical properties of electrospun zein fibers, plasticizers (glycerol, lactic acid, and oleic acid) or co-proteins (casein, whey protein, rice protein) were mixed with zein using the solvents acetic acid or aqueous ethanol with or without sodium hydroxide. Incorporating plasticizers or co-proteins had a negligible impact on solution viscosity, solution surface tension, and fiber formation, although electron microscopy of fiber mats showed an increase in bead formation with added co-proteins. Gel electrophoresis identified casein and whey protein in spun mats. Infrared spectra demonstrated the inclusion of plasticizers in fiber mats. Glycerol, lactic acid, and oleic acid reduced the glass transition temperature of bulk fibers. Nanoindentation tests of individual fibers found reduced Young's moduli with added lactic or oleic acids but increased moduli with added casein. Thus, electrospinning zein with food-grade plasticizers or proteins physically modifies fibers, yet incorporating significant protein quantities remains a challenge.

Production and characterization of lignocellulosic fractions from sisal waste

An integrated fractionation process, UV-catalyzed hydrogen peroxide pretreatment (UHP) with subsequent alkali and acidic ethanol extraction, was developed to consecutively recover cellulose, hemicellulose, lignin and pretreated liquid fractions from sisal waste. These fractions serve as a viable source of high-value industrial chemicals. Delignification rate reached approximately 80 % under the UHP pretreatment with 0.1 mL/g H2O2 for 6 h. The pretreated sisal waste was further fractionated into four parts, cellulose (35.5 g/100 g sisal waste), xylan-rich hemicellulose (12.5 g/100 g sisal waste), acid-insoluble lignin (5.7 g/100 g sisal waste) and the liquid fraction (21.0 g/100 g sisal waste). The cellulose fraction was in high purity with increased crystalline index of 51.4 %, and the hemicellulose fraction was rich in xylan. The lignin fraction had the GSH-type structure with some ferulic acid residues bound mainly via β-O-4 linkages. The liquid fraction had a high content of phenolic compounds (16.26∼41.88 mg GAE/L) with strong antioxidant activities, 11.16∼18.48 μmol TE/L reducing power, 66.78∼82.84 μmol TE/L hydroxyl radical scavenging and 14.83∼46.67 μmol TE/L ABTS radical scavenging.

Preparation of Acid Red73 adsorbed on chitosan-modified sepiolite with SiO2 coating as a highly stable hybrid pigment

The application of organic dyes in industry is severely limited due to its insolubility and instability. The adsorption of organic dyes by inorganic materials to form hybrid pigment is a valid method to improve its stability, thus widening its applications in industries. A simple method for preparing stable hybrid pigment by adsorpting Acid Red 73 (AR73) on the chitosan (CTS) modified sepiolite with a SiO2 coating is explored in this work. Sepiolite modified by the CTS was used to immobilize AR73 (CTS-sep/AR73) uniformly to form a hybrid pigment. The effects of the dosage of CTS, the concentration of acetic acid (HAc) and the pH of AR73 solution for CTS-sep adsorption of AR73 were investigated. CTS-sep/AR73 was further coated with a layer of SiO2 to form the CTS-sep/AR73@SiO2 pigment, which enhanced the stabilities of the hybrid pigment. The CTS-sep/AR73@SiO2 pigment shows excellent stability in strong acid, strong alkali and anhydrous ethanol environment, along with the improved thermal ageing, intensified UV resistance, and enhanced thermal stability (more than 220 °C) which is higher than that of CTS-sep/AR73 hybrid pigment.

Microscopic Studies, Mineral composition and Bioactivity of Vitex madiensis Oliv. (Lamiaceae)

Ethanol and organic acid extracts from the leaves of Vitex madiensis Oliv. were evaluated for their antihelminthic activity using the animal model of Benhamia rosea and B. itoleisis (Kinshasa/DRC earthworms), antibacterial activity and antioxidant activity. Different concentrations (5 mg/mL, 2.5 mg/mL, 1.25 mg/mL and 0.625 mg/mL) of standard Albendazole (positive control) and sample solutions (organic acid extracts and ethanol extracts) were used for this study which involved the determination of the paralysis time (vermifuge) and mortality time (vermicidal activity) of the worms. The presence of different secondary metabolites was determined by the thin layer chromatography. The results obtained showed that the ethanolic extract and the organic acid extracts showed significant antihelminthic activity. Microscopic examination of the parts used revealed the presence of various histological elements. Its phytochemical profile remains dominated by various secondary metabolites such as coumarins, anthraquinones, flavonoids, phenolic acids and terpenoids. The mineral composition was determined by inductively coupled argon plasma optical emission spectrometry (ICP-EOS) showed the abundance of various elements, namely calcium, iron, potassium, selenium, sodium, magnesium, manganese, nickel, phosphorus, cobalt, copper, barium and zinc in this plant. The antibacterial activity of the extracts of this plant was weak against the bacterial strains tested. The organic acid and ethanol extracts showed interesting antioxidant activity. The leaves extracts of Vitex madiensis Oliv. showed good antihelminthic, antibacterial and antioxidant activities related to their phytochemical compositions. All these results constitute scientific evidence validating the use of this medicinal plant for the management of parasitic infections of small ruminants in the Democratic Republic of the Congo.

Boosting alcohol electro-oxidation reaction with bimetallic PtRu nanoalloys supported on robust Ti0.7W0.3O2 nanomaterial in direct liquid fuel cells

In this work, an anatase Ti0.7W0.3O2-supported Pt3Ru nanoparticles (NPs) were fabricated by combining the advantages of the non-carbon Ti0.7W0.3O2 nanosupport and the synergistic effect of the bimetallic Pt3Ru nanoalloy that was investigated as electrocatalyst toward alcohol electrochemical oxidation. The bimetallic Pt3Ru nanoparticles with ~3 nm in diameter were relatively well-dispersed on the surface of the anatase Ti0.7W0.3O2 nanosupport via a surfactant-free microwave-assisted polyol route that, which was attributable to the good dispersibility of ethylene glycol and the rapid, uniformity of the microwave heating. For methanol and ethanol electrochemical oxidation, the as-obtained Pt3Ru (NPs)/Ti0.7W0.3O2 electrocatalyst exhibited the low onset potential (~0.10 V vs. NHE for MOR and ~0.35 V vs. NHE for EOR) and high mass activity (~350.84 mA mgPt−1 for MOR and ~274.59 mA mgPt−1 for EOR) compared to the commercial Pt (NPs)/C (E-TEK) electrocatalyst. Additionally, the CO-stripping and CA results indicated the remarkably enhanced CO-tolerance of the Pt3Ru (NPs)/Ti0.7W0.3O2 catalyst. After the 5000-cycle accelerated durability test (ADT) in acidic ethanol media, the bimetallic Pt3Ru (NPs)/Ti0.7W0.3O2 catalyst only showed the mass activity loss of 19.11% of its initial mass activity, compared with the severe deterioration of 44.04% of the commercial Pt (NPs)/C (E-TEK) catalyst. The outstanding results could be interpreted due to the bifunctional mechanism of the Pt3Ru nanoalloys combining with the synergistic effect between the bimetallic nanoalloy and the mesoporous Ti0.7W0.3O2 nanosupport as well as the superior anti-corrosion of the TiO2-based nanosupport under acidic and oxidative environments.

Influence of Substituents in the Aromatic Ring on the Strength of Halogen Bonding in Iodobenzene Derivatives

Halogen bonding properties of 3,4,5-triiodobenzoic acid (1, 2), 1,2,3-triiodobenzene (3), pentaiodobenzoic acid ethanol solvate (4), hexaiodobenzene (5a, 5b, 5c), 2,4-diiodoaniline (6), 4-iodoaniline (7), 2-iodoaniline (8), 2-iodophenol (9), 4-iodophenol (10), 3-iodophenol (11) and 2,4,6-triiodophenol (12) has been studied. The results suggested that substituents other than halogen in aromatic ring affect XB properties of iodine substituents in ortho-, meta- and para-positions. The effect depends on the electron-withdrawing/electron-donating properties of the substituent. Thus, electron-withdrawing substituents with negative mesomeric effect favor m-iodines to act as XB donors and o- and p-iodines to act as XB acceptors. By contrast, electron substituents with positive mesomeric effect favor o- and p-iodines to act as XB donors and m-iodines to act as XB acceptors.

A theoretical study on dimerization and dissociation of acetic acid in ethanol solvent

Electronic structure calculations are applied on acetic acid monomers, dimers and clusters in water and ethanol solvent. Acetic acid is normally existed as dimeric structure in gas, vapor and liquid phase. It is predicted that sufficient ethanol molecules can dissociate this dimeric structure, while stable clusters can be formed by acetic acid units and ethanol units. To investigate this process, optimized structures, geometry parameters, interaction energy values and simulated Raman spectra of acetic acid dimers and clusters are discussed. Geometry parameters indicates that at least three ethanol molecules can break the dimeric structures, while just two H2O molecules are needed to dissociate acetic acid dimer. Interaction energy parameters justify the minimum number of solvent molecules to break dimeric structures further. Energy decomposition analysis of interaction suggests that hydrogen-bond interaction plays a central role in interaction and acetic acid clusters with ethanol units have higher value of electrostatic energy than that of hydrated clusters, which causes that more ethanol molecules are needed to break acetic acid dimer than water molecules. Reduced density gradient function analysis investigates the position and strength of H-bond interaction. The red shifts of the OH peak position of theoretical spectra for acetic acid clusters imply the weakening of OH stretching and the strengthen of H-bond interaction while clusters’ size enlarging. Experimental Raman spectra justify the result of theoretical spectra.

Recommendations on quality standards of Andrographis Herba and its processed slices in Chinese Pharmacopoeia (2020 edition)

To improve and perfect the quality standards and propose recommendations for the revision of quality standards for Andrographis Herba and its processed slices in Chinese Pharmacopoeia(ChP)(2020 edition) based on the problems and limitations in ChP(2015 edition). TLC identification method with andrographolide and control herbs as references was established using silica gel G thin layer plate, with chloroform-methylbenzene-methanol(8∶1∶1) as developing solvent, and 10% sulfuric acid ethanol solution as colour-developing agent. This method has good reproducibility, strong specificity and high sensitivity. As compared with the original method in ChP 2015, this method has better development effect and clearer spots. Based on the previous research, a quantitative analysis of multi-components by single-marker(QAMS) method with andrographolide as the internal reference substance was developed to simultaneously determine the contents of 4 diterpene lactones: andrographolide(S), neoandrographolide(A), 14-deoxyandrographolide(B), and dehydroandrographolide(C). The relative correction factors of f_(A/S), f_(B/S), and f_(C/S) were determined as 1.12, 0.79, and 0.63, respectively. The relative retention time of t_(A/S), t_(B/S), and t_(C/S) was 1.95, 2.18, and 2.25, respectively. According to the content determination results in 46 batches of crude drugs and 38 batches of processed slices, it was stipulated that the total contents of 4 diterpene lactones should not be less than 1.5% and 1.2% in crude drugs and processed slices, respectively. As compared with the original method in ChP 2015, the present QAMS method could not only reduce the detection cost and improve the efficiency, but also can be used to evaluate the quality of Andrographis Herba and its processed slices more comprehensively and objectively. Diterpene lactones are generally recognized as the effective components in Andrographis Herba, and their contents in leaves were much higher than those in stems. However, almost all of the current commercial processed slices are processed from stems, so their quality is gene-rally poor and the efficacy is hard to be guaranteed. Therefore, the weight percentage of leaves should be added into the inspection items of the processed slices and it should not be less than 25%.

High Antioxidant Activity of Pucuk Merah (Syzygium oleina) Leaf and Zinnia (Zinnia elegans) Flower Extracts

A study on the antioxidant activity of natural sources is very crucial to explore their benefits, especially for food, medicine, as well as cosmetic applications. In this work, the antioxidant activities of pucuk merah (Syzygium oleina) leaves and zinnia (Zinnia elegans) flower were examined. Pucuk merah leaves and zinnia flowers were extracted using an acidic ethanol solvent by a simple maceration method for 24 hours. The color of the obtained pucuk merah leaf extract was red, while the zinnia flower extract was yellowish-brown. UV-visible spectrophotometer showed that the pucuk merah leaf extract has anthocyanin as the main part and chlorophyll as the minor part. On the other hand, zinnia flower extract contained carotenoid as the main part, as well as small parts of anthocyanin and chlorophyll. The antioxidant activity test was carried out by using 2-2-diphenyl-1-picrylhydrazyl (DPPH) as the antioxidant assay. It was revealed that the inhibitory concentration at 50% (IC50) values of the pucuk merah leaf and zinnia flower extracts were 25.83 and 20.16 mg/L, respectively, while the antioxidant activity index (AAI) of the pucuk merah leaf and zinnia flower extracts were 1.55 and 1.98, respectively. These results showed that both pucuk merah leaf and zinnia flower extracts have strong antioxidant activity, and thus very potential to be used as great antioxidants.

Developing a Commercial Antimicrobial Active Packaging System of Ground Beef Based on “Tsipouro” Alcoholic Distillate

The present study aimed to develop a commercial active packaging system of ground beef, by exploiting the antimicrobial and antioxidant properties of a traditional Greek alcoholic distillate called “tsipouro”. Commercial packages (500 g) were used and 40 mL of “tsipouro” was added in absorbent pads placed underneath the ground beef, while 10 mL was also mounted under the packaging film, facing the headspace. Samples were packaged in 80% O2: 20% CO2 and stored at 0, 4, 8, and 12 °C. Total Viable Counts, pseudomonads, Brochothrix thermosphacta, lactic acid bacteria, yeasts-moulds, pH, colour (L*, a*, b*), odour (buttery and acidic), and ethanol migration to ground beef (SPME/GC-FID) were determined. Moreover, mathematical models (square root and Arrhenius) describing the effect of temperature on determinant indicators of spoilage and quality deterioration like growth of dominant microorganisms and red colour reduction were developed and validated under non-isothermal conditions. B. thermosphacta dominated the microbial association of ground beef, while LAB were second in dominance, revealing a high growth potential at all assays. a* value (redness) was gradually decreased in controls, while samples treated with “tsipouro” showed more stable red colour during storage. Although ethanol was organoleptically detectable, especially at low storage temperatures (0–4 °C), it was rather perceived as a pleasant cool odour. Prediction by both models for microbial growth as well as those of Arrhenius model for reduction of a* value showed good agreement with the observations under non-isothermal storage. Overall, our study showed that the developed antimicrobial active packaging of ground beef based on “tsipouro”, combined with high oxygen MAP lead to an almost 2-fold shelf-life extension compared with controls during storage at chill and abuse temperatures.

To Assess the Level of Salivary Calcium after the Consumption of Carbonated Soft Drinks

Diet is a major etiological factor for enamel erosion and dental caries. The proportionality of dental caries increases with the increase in duration of food in the oral cavity. This study was undertaken with the aim of assessing the level of salivary calcium with the consumption of beverages. Major chemical constituents of beverages include, carbohydrates, sweeteners, acids (pH-2.5 to 3.5) phenolic compounds, steroids, nitrogen compounds, ethanol (for alcoholic beverages) and carbon dioxide (for carbonated soft drinks). The presence of carbon in the soft drinks reduces the pH leading to demineralisation and erosion of enamel layer when consumed. The sugars and carbon present in the soft drinks are responsible for dissolution of enamel. Thus the aim of the current study is to analyse the effect of carbonated soft drinks on salivary calcium level. In this study 25 subjects were selected. All were given 200ml of carbonated soft drinks immediately after opening the soft drinks bottle to avoid cessation of carbon dioxide. The level of salivary calcium is measured and analysed by paired sampling using a commercially available analyser kit and the results were statistically analysed, compared and interpreted. There is an increase in the salivary calcium level after the consumption of carbonated soft drinks because of its acidic ph and sugar content. The acidic environment causes demineralisation of the enamel making the enamel brittle and weaker. From this Study, it can be verified that the level of calcium in the saliva increases due to the action of the carbon and sucrose present in the soft drinks on the enamel. This can be verified with the significant p value (p&lt;0.005).

Separation of Scandium from Hydrochloric Acid-Ethanol Leachate of Bauxite Residue by a Supported Ionic Liquid Phase.

Solvometallurgy is a new branch of extractive metallurgy in which green organic solvents are used instead of aqueous solutions to improve selectivity in separation processes. In the present study, nonaqueous leaching of a Greek bauxite residue (BR) was performed and scandium was separated from other elements in the leachate by column chromatography. At first, the selectivity of sorbents for scandium(III) over iron(III) was tested in batch mode using various organic solvents. The following three sorbents were tested: (1) a carboxylic acid-functionalized supported ionic liquid phase (SILP), (2) silica (SiO2), and (3) silica functionalized with ethylenediaminetetraacetic acid (SiO2–TMS–EDTA). The best separation of scandium and iron was achieved from ethanolic solution by the SILP. The BR was then leached with 0.7 mol L–1 HCl in ethanol or in water. The leaching efficiency of scandium with both lixiviants was similar. However, much less sodium was leached, and silica remained in solution when leaching was performed with the ethanolic lixiviant. By using ethanol as opposed to water, the serious drawback of silica gel formation that is taking place in the aqueous leachate of BR was circumvented. The sorption preference of the SILP for metal ions in the ethanolic leachate was partly reversed compared to the aqueous leachate. Iron was separated from other metals of the ethanolic BR leachate by a simple elution with ethanol. The formation of the anionic tetrachloroferrate(III) complex, [FeCl4]−, enabled the selective elution. This complex was not observed in the aqueous leachate of BR. Scandium was separated from the vast majority of other components of the BR by elution with 0.1 mol L–1 H3PO4.