Ethanol Volume Fraction Research Articles

Concomitant Polymorphism and Nucleation Control of DL‐Methionine Through Antisolvent Crystallization

AbstractThe concomitant polymorphism of the sulfur‐containing essential amino acid DL‐methionine was revealed, and α‐ and β‐polymorphic forms were separated from aqueous solution through antisolvent crystallization with ethanol as antisolvent. The addition of different volume fractions of ethanol into the mother solution reduces the solubility of DL‐methionine in double‐distilled water and in turn proportionately generates a range of supersaturation levels. This induces the nucleation of a stable β‐polymorph at low supersaturation levels, a mixture of α‐ and β‐ polymorphs at intermediate supersaturation levels, and a metastable α‐form at high supersaturation levels. Needle‐shaped α‐polymorphs and platy‐shaped β‐polymorphs were well distinguished through in‐situ optical microscopic analysis and their structural confirmation was done by X‐ray diffraction analysis.

Simple and efficient fabrication of multi-stage color-changeable photonic prints as anti-counterfeit labels

Color changeable photonic prints (CCPPs) show their potential applications in high-level information storage and anti-counterfeiting, but usually suffer from the complex fabrication process and limited color variation. Here, a simple and efficient method is developed to generate CCPPs with multilevel tunable color contrasts by packing the solvent responsive photonic crystals with diverse cross-linking degrees and desired way. The key to the successful fabrication is to create and control over the optical response of each part of the CCPPs through altering the cross-linking degree of PCs and thus the affinity between the CCPPs and solvents. A CCPPs based anti-fake label with the encrypted information functionality which originates from reversible color change between dried state and swelling with the mixture of acetic acid and ethanol is investigated. Compared with conventional CCPPs, the as-prepared CCPPs can reveal multistage information depending on the volume fraction of ethanol. This work provides a new insight for the simple fabrication of CCPPs and will facilitate their applications in the information protection and high-level anti-counterfeiting.

Extraction and purification of total flavonoids from Gnaphalium affine D. Don and their evaluation for free radicals’ scavenging and oxidative damage inhabitation potential in mice liver

The parameters for pressurized microwave-assisted extraction (PMAE) of total flavonoids (TFs) from Gnaphalium affine D. Don were investigated and the effect of PMAE on its cell wall and tissue structure was analyzed via scanning electron microscopy (SEM). Afterwards, its extraction effect was compared with that of microwave-assisted extraction (MAE), soxhlet extraction (SE) and heat reflux extraction (HRE). After purifying by AB-8 macroporous resin, the in vitro and in vivo antioxidant activities of purified TFs were evaluated by five different chemical assays and alcohol-induced model, respectively. Our findings revealed that an ethanol volume fraction of 81.3%, a L/S ratio of 25.4 mL/g and an extraction time of 138 s, give maximum yield of TFs (1.35 ± 0.02%). PMAE was more efficient and rapid in extracting TFs from G. affine because it cracked the cell wall and disrupted the tissue structure, as observed by SEM. Compared with microwave-assisted extraction (MAE), soxhlet extraction (SE) and heat reflux extraction (HRE), PMAE was more efficient and rapid technique for the extraction of TFs from G. affine. TFs from G. affine showed notable free radical, including 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide anion, 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt (ABTS) cation, scavenging abilities and reduction ability in vitro. It could also significantly reduce the level of malondialdehyde (MDA), enhance the activity of superoxide dismutase (SOD) and total antioxidant capacity (T-AOC), and increase the level of glutathione (GSH) in the liver of mice with oxidative damage in a dose-dependent manner. Therefore, it showed good antioxidant capacity in vivo. TFs from G. affine indicated good in vitro and in vivo antioxidant activities, which suggests their potential in functional foods and pharmaceuticals as natural antioxidants agents.

Optimization of the Application of Walnut Green Peel Pigment in Wool Fiber Dying and Fixing Process under Microwave-assisted Condition

ABSTRACT In this paper, the response surface method was used to study the technology of dyeing wool fiber with walnut green peel pigment under the microwave-assisted method. The optimized pigment extraction process were: ethanol volume fraction 60%, extraction time 1 min, liquid-material ratio 24:1, microwave power 450 W, and the optimized mordant fixation process were: mordant fixation time 3 min, microwave power 270 W, amount of mordant fixing agent 7%, reducing agent dosage 22 g/L. The results showed that the use of microwave-assisted and new mordant fixing agent lanthanum chloride greatly improved the extraction efficiency of pigments, saved extraction costs, and significantly shortened the mordant fixation time, resulting in an environmentally friendly mordant fixation process.

The spectral study of azo dye and cationic surfactant interaction in ethanol-water mixture

The interaction of the azo dye methyl red (MR) with dodecyl trimethyl ammonium bromide (DTAB) has been studied by the spectrometric methods through the azo-hydrazone tautomeric behaviour of MR for a series of the ethanol?water system (0.1, 0.2, 0.3 and 0.4 volume fractions of ethanol) at room temperature. The critical micelle concentration was determined using the conductometric technique with the increased ethanol volume, influenced by the solvent polarity and the architectural flexibility of methyl red. The azo form of methyl red brings the electrostatic interaction with the cationic surfactant through the adsorption phenomenon. The binding parameters were calculated with the aid of a modified Benesi?Hildebrand equation.

Conductivity Study of DTAB in Water and Ethanol-Water Mixture in the Presence and Absence of ZnSO4

The physicochemical behaviour of dodecyltrimethylammonium bromide (DTAB) in water and ethanol-water mixture in the presence and absence of ZnSO4 were studied by measuring the conductivity at 298.15 K. The pre-micellar (S1) and post-micellar slopes (S2) were obtained and calculated the degree of dissociation (α) and the critical micelle concentration (cmc). With an increase in ethanol content, the cmc and α of DTAB increased whereas, in the presence of ZnSO4, the cmc and α decreased. By using cmc and α, thermodynamic properties as the standard free energy of micellization ( ) were evaluated. With an increase in ethanol content, the negative values of are decreased indicating less spontaneous in the micellization which makes micellization less favourable. The correlation of the pre-micellar and post-micellar slopes with the volume fraction of ethanol were discussed. DTAB micellization was tested in contexts of specific solvent parameters and solvophobic parameter.

Optimization of Extraction Process of Polyphenols from Annona squamosa Leaves and Its Antioxidant Activity in Vitro

In this experiment,the raw material was Annona squamosa leaves,and the polyphenol substances in the leaves were extracted by using ethanol solvent. The effects of ethanol volume fraction,extraction temperature,liquid-solid ratio and extraction time on the polyphenol extraction amount were respectively compared. The Box-Benhnken center combination test in response surface methodology was used to determine the optimal extraction process. DPPH radical and hydroxyl radical(·OH)methods were used to study the antioxidant activity of polyphenols from Annona squamosa leaves,and the scavenging ability of polyphenols from Annona squamosa leaves and ascorbic acid extracted under the optimal process conditions were compared. The results showed that when the volume fraction of ethanol was 55%,the ratio of liquid to solid was 50:1 (mL/g),the extraction time was 96 min,and the extraction temperature was 60 ℃,the extraction amount of polyphenol was the largest,reached(20.37±0.34) mg/g.The semi-inhibitory concentrations(IC50)of polyphenols from Annona squamosa leaves on DPPH radical and hydroxyl radical(·OH)were 133.33 and 264.65 μg/mL respectively. The maximum scavenging rates of the samples in the test range were(51.34%±2.68%)and(52.50%±2.29%)respectively. In summary,the polyphenols from Annona squamosa had good antioxidant capacity and would provide theoretical basis for the development of polyphenols from Annona squamosa.

A Novel Green Extraction Technique for Extracting Flavonoids from Folium nelumbinis by Changing Osmosis Pressure.

A new green and sustainable extraction technique, namely osmosis extraction (OE), was developed for efficient extracting flavonoids from Folium nelumbinis by changing the osmotic pressure. The antioxidant activities of the extracted flavonoids were also evaluated. Ethanol and ammonium sulfate were selected for the OE system because they are environmentally friendly. The maximum flavonoids concentration in the top phase was obtained with an ethanol volume fraction of 42.0% and the salt mass of 1.9 g. The kinetic behavior of the extraction process showed that OE had higher efficiencies especially coupled with ultrasonication due to the accompanying and serious morphological changes of Folium nelumbinis cells observed by digital microscope and nano-computed tomography (nano-CT). Results of morphological and anatomical features showed that the higher intracellular chemical potential made the cell expand and even led to bursting. The results also showed that the extraction efficiency of flavonoids with high antioxidant activities was higher than that of the traditional method. The interface effect enhanced the extraction during the salting-out extraction and osmosis was the main factor that improved the extraction efficiency.

Soot Formation With Light Extinction and Grayscale Extraction Methods Applied to Ethanol-Gasoline Blends Laminar Flame

AbstractIn this paper, the two-dimensional parallel light extinction method was carried out to study the soot formation in laminar diffusion flames of four different ethanol-gasoline blends, of which ethanol volume fractions ranging from 0% up to 100% (E0, E20, E80, and E100). The flame images were processed synthetically via matlab to accurately calculate the flame height. In addition, the flame structure was redefined as three zones to observe the soot formation. The results indicate that the flame height changes with the variation of gas volume flowrate and fuel mass flowrate during the experiment. In terms of soot formation, as the volume fraction of ethanol increases, the proportion of soot forming zone decreases, while the area of blue flame zone grows. Simultaneously, the transition zone accounts for about 21% of the total flame area, which has no significant change with the increase of ethanol volume fraction.

Interlaboratory comparisons on determining of alcohol by volume (abv) in vodka Measurement standards

The article provides an analysis of accuracy indicators for measuring the alcohol by volume (ABV) in vodka performed by various methods according to GOST 32035–2013 «Vodka and Special Vodka. Acceptance Rules and Methods of Anlysis». The results of two rounds of the interlaboratory comparisons on determination of the ABV in vodka conducted to verify the qualifications of accredited testing laboratories are described.Information is provided on the development of the GSO 11142–2018 reference material for the volume fraction of ethanol in an aqueous solution (VER-2), certified for the volume fraction of ethanol in an aqueous solution, instances of which were used during the interlaboratory comparisons. The conclusion is made about the satisfactory quality of measurements of ABV in vodka in the accredited laboratories.

Ultrasound-Assisted Extraction of Taxifolin, Diosmin, and Quercetin from Abies nephrolepis (Trautv.) Maxim: Kinetic and Thermodynamic Characteristics.

Extraction behaviors of the 3 flavonoids taxifolin, diosmin, and quercetin have been investigated in Abies nephrolepis leaves and bark. The following operation parameters—ethanol volume fraction, liquid–solid ratio, temperature, ultrasound irradiation power and time, and ultrasound frequency—were varied to study their effect on the yield of the 3 flavonoids during extraction. The results showed that a low extraction efficiency occurred at 293.15 K due to slow kinetics, while the situation was significantly improved at 333.15 K. The kinetic data for the extraction yields of the 3 flavonoids achieved good fits by the first-order kinetic model. From the thermodynamic analysis results, we realized that the ultrasound-assisted extraction of taxifolin, diosmin, and quercetin from the leaves and bark of A. nephrolepis was a spontaneous and endothermic process in which the disorder increased (ΔG0 < 0, ΔH0 > 0, and ΔS0 > 0). According to the response surface methodology (RSM) analysis, under the optimal operation conditions (ethanol concentration of 50%, liquid–solid ratio of 20 mL/g, frequency of 45 kHz, extraction time of 39.25 min, ultrasound irradiation power of 160 W and temperature of 332.19 K), the total yield of the 3 flavonoids were 100.93 ± 4.01 mg/g from the leaves of A. nephrolepis (with 31.03 ± 1.51 mg/g, 0.31 ± 0.01 mg/g, 69.59 ± 2.57 mg/g for taxifolin, diosmin, and quercetin, respectively), and under the optimal operation conditions (ethanol concentration of 50%, liquid–solid ratio of 20 mL/g, frequency of 45 kHz, extraction time of 36.80 min, ultrasound irradiation power of 150 W and temperature of 328.78 K), 16.05 mg/g ± 0.38 mg/g were obtained from the bark of A. nephrolepis (with 1.44 ± 0.05 mg/g, 0.47 ± 0.01 mg/g, 14.14 ± 0.38 mg/g for taxifolin, diosmin, and quercetin, respectively), which were close to the prediction values.

Densities, Refractive Indices, and Derived Properties of Binary Mixtures of Ethanol with Benzene and Pyridine at Various Temperatures Under Atmospheric Pressure

Experimental densities at (293.15, 298.15, 303.15, 308.15, and 313.15) K and refractive indices at 298.15 K are reported for the binary liquid mixtures of ethanol with benzene and pyridine over the entire range of compositions and atmospheric pressure. From these experimental data, the excess molar volumes VE and deviations in molar refractivity ΔR were derived and fitted by the Redlich–Kister polynomial to determine the adjustable fitting parameters and the standard deviations. The number of adjustable parameters to be included in a Redlich–Kister polynomial for fitting the derived properties was optimized with the F-test. VE values are found to be negative over the entire composition range in ethanol + pyridine mixtures, without considerable changes over the temperature range studied. In the ethanol + benzene mixtures, the VE results show an S-shaped composition dependence, and the temperature contribution was found to be very important. The variation of VE with composition and temperature has been interpreted in terms of molecular interactions between the components of the mixture and structural effects. ΔR values are found to be negative for both mixtures with a minimum located between 0.45 and 0.5 volume fractions of ethanol. Furthermore, several theoretical and empirical mixing rules were applied to predict refractive indices of mixtures in order to test their validity for the present systems.

Microfluidic sensor applications by using chiral metamaterial

Chiral metamaterial-based sensor is designed for sensing the change in substance ratio of chemical substances when combined with distilled water. These samples have been prepared with 10%, 50% and 90% volume fraction of methanol, ethanol, acetone, ammonia and isopropyl alcohol. The complex permittivity of the prepared samples has been measured by Agilent 85070E dielectric probe kit and compared with the simulations. In the proposed design, linear shifts with the frequency bands of more than 100 MHz are observed in different measurements. For different material sensing, pure samples have been used and their reflection coefficient measurement results have been presented. Unique side of this study is that the structure provides very clear and sensitive results and presents a new approach to the microfluidic sensor applications by using the sample holder.

Optimization of Ultrasound-Assisted Extraction of Polyphenols from Xanthoceras sorbifolia Husks and their Determination using HPLC

X. sorbifolia can be used as both food material and medicinal plant. In this study, ultrasound-assisted extraction (UAE) was firstly used to optimize the extraction process of total polyphenols from X. sorbifolia husks. Ultrasonic time, ultrasonic temperature, ratio of solvent to material and volume fraction of ethanol were investigated and optimized by orthogonal experiments. Then, High Performance Liquid Chromatography (HPLC) was applied to analyze the polyphenols of the extract under the optimal extraction process. The optimized results for UAE was 40 min of ultrasonic time, 40 ℃ of ultrasonic temperature, 100:1 mL/g of solvent to material ratio and 60% aqueous ethanol. Under the optimal extraction process, the total polyphenol content (TPC) of the extract was 23.16 mg GAE/g DW. Furthermore, the most abundant polyphenols in X. sorbifolia husks extract, such as gallic acid, protocatechuic acid, epicatechin, myricetin-3-O-β-D-rutinoside, rutin and quercetin, were analysed using HPLC. In addition, UAE extract showed antioxidant activity in a concentration-dependent manner. Accordingly, X. sorbifolia husks can be used as a rich source of natural antioxidants. To sum up, these results provided a solid chemical basis underlying the future research and application of Xanthoceras sorbifolia husks.

Optimization of Ultrasound-Assisted Extraction of Polyphenols from Xanthoceras sorbifolia Husks and their Determination using HPLC

X. sorbifolia can be used as both food material and medicinal plant. In this study, ultrasound-assisted extraction (UAE) was firstly used to optimize the extraction process of total polyphenols from X. sorbifolia husks. Ultrasonic time, ultrasonic temperature, ratio of solvent to material and volume fraction of ethanol were investigated and optimized by orthogonal experiments. Then, High Performance Liquid Chromatography (HPLC) was applied to analyze the polyphenols of the extract under the optimal extraction process. The optimized results for UAE was 40 min of ultrasonic time, 40 ℃ of ultrasonic temperature, 100:1 mL/g of solvent to material ratio and 60% aqueous ethanol. Under the optimal extraction process, the total polyphenol content (TPC) of the extract was 23.16 mg GAE/g DW. Furthermore, the most abundant polyphenols in X. sorbifolia husks extract, such as gallic acid, protocatechuic acid, epicatechin, myricetin-3-O-β-D-rutinoside, rutin and quercetin, were analysed using HPLC. In addition, UAE extract showed antioxidant activity in a concentration-dependent manner. Accordingly, X. sorbifolia husks can be used as a rich source of natural antioxidants. To sum up, these results provided a solid chemical basis underlying the future research and application of Xanthoceras sorbifolia husks.

Study on the Different Method of Extraction of Star Anise Oil

The three reagents of anhydrous ethanol, petroleum ether and ethyl acetate were selected by soxlet extraction, steam distillation and ultrasonic extraction to extract the star anise oil from the fine anise powder. Three kinds of methods for extracting star anise oil were studied on different pattern organic solvent. The result of the different volume fractions of ethanol is that the highest extraction rate is 99.7% ethanol. It can be seen that the extraction rate are: ethanol &gt; petroleum ether &gt; acetic acid ethyl ester. The different methods of extracting the star anise oil shows that the extraction rate are: soxhlet extraction method &gt; ultrasonic extraction method &gt; steam distillation extraction method. In summary, it can be seen by soxhlet extraction method and the best solvent is 99.7% ethanol.

Visual binary testing of methanol contained in ethyl alcohol

A method for control of methanol traces in rectified ethyl alcohol and alcoholic drinks based on visual binary testing using one reference sample was proposed. An indicator reaction of formaldehyde interaction (product of methanol oxidation) with chromotropic acid disodium salt was chosen for methanol screening. The conditions of indicator reaction proceeding are analogous as for the spectrophotometric technique of methanol determination: methanol was oxidized to formaldehyde with potassium permanganate in an acidic medium; the formaldehyde then reacts with chromotropic acid in the presence of hot concentrated sulfuric acid and forms a violet product (color of this product is stable for 12 hours). It was established that the absorption spectrum of the reaction product does not change on going from 96% ethanol to aqueous-ethanol solutions with a volume fraction of 40% ethanol. The maximum light absorption of the reaction product corresponded to 570 nm. All further studies were carried out in water-ethanol solutions with a volume fraction of ethanol of 40%. According to regulatory documents the normalized limiting content of methanol (clim) in ethyl alcohol of the “Lux” grade (the most common in the alcoholic industry) and alcoholic beverages is 0.01% by by volume counted upon anhydrous alcohol. The comparison sample (the solution of colored reaction product of indicator reaction) had to be less than the normilized level on the value which providing the risk of false-negative test result not more than 5%. To determination the threshold concentration of methanol in the comparison sample was applied the statistics of observation. For the aim the solution of colored product corresponding to the normalized limiting methanol concentration clim = 0.01% by volume was prepared and comparison samples with lower methanol concentrations were also prepared. The interval of unreliability was discovered with the help of observers. The frequency of detecting of the difference in the color of comparison samples and normalized sample (P(c)) changed from 0 to 1 in this interval. The value of methanol concentration 0.0072% by volume counted upon anhydrous alcohol was taken for the lower boundary of the interval and the value of methanol concentration 0.01% by volume counted upon anhydrous alcohol was chosen the upper border of the interval. This interval was divided on eight concentrations with step Dс = 0.0004% by volume. Three parallel series of solutions were prepared and 48 observations for each concentration were received. The experimental efficiency curve obtained was checked for compliance with the mathematical functions of the known distributions: normal, logistic, lognormal, exponential and Weibull distribution function using the statistical criterions c2 and Kolmogorov-Smirnov λ. The efficiency curve was described by the theoretical functions of the lognormal and Weibull distributions. Calculated at a confidence level of 0.95 estimation of the threshold concentration for the comparison sample was 0.0073% by volume fraction corresponding to anhydrous alcohol. The visual binary testing of methanol trace in alcoholic drinks was carried out. The accuracy of visual binary testing of methanol was confirmed by gas chromatography.

Studying the biochemical transformations in sherry wines subjected to biological aging

The fundamental role in the process of biological aging is given to yeast which enrich the wine with substances that contribute to the formation of the characteristic organoleptic properties of sherry. We studied 55 samples of wine in the dynamics of biological aging. The purpose of this research was to study the transformation of wine components during biological aging and to determine their technological value. Generalization of experimental data showed that biological aging determines changes in the composition of wines and physical-chemical characteristics: reduction of the volume fraction of ethanol, the mass concentration of the components of the acid complex (malic, lactic and acetic acids), amine nitrogen and glycerin as sources of energy and carbon nutrition for yeast. Decrease in the content of phenolic substances, the value of the redox-potential of wine and optical density D420 confirms the protective function of the sherry film that prevents non-enzymatic oxidation of wine components. The biological aging is also characterized by an increase in the mass concentration of aroma-forming substances: acetaldehyde, diacetyl, acetoin, dioxanes, dioxolans, lactones. Based on the data obtained, the role of the main components of wines in the process of biological aging and the ranges of their variation were determined.

Optimization of extraction of polysaccharides from Suaeda salsa (L.) Pall. by ultrasonic: characterization, purification and antioxidant assessment

Under optimal extraction conditions, characterization and antioxidant activity of polysaccharides from the Suaeda salsa (L.) Pall. were investigated. This was the first report that described the composition of the polysaccharide form this plant. Obviously, the yield of 2.19% for extraction of polysaccharides was obtained as ethanol volume fraction of 65%, extraction time of 72 min, ultrasound assisted power of 438 W, and temperature of 85°C, respectively. The structure study was carried out with FT-IR and SEM, and the chemical contents of carbohydrates, proteins, uronic acids and total flavonoids were measured in this study. The crude polysaccharides were purified into two components including SGP-1-1 and SGP-2-1. Moreover, the chemical composition analysis according to HPLC showed that it was viscous polysaccharide, which mainly contained glucose, mannose, xylose, galacturonic acid, glucuronic acid, fucose, rhamnose, arabinose, galactose, respectively. Besides, it was proved that the optimum polysaccharides possessed higher significant potentials (P&lt;0.05) in scavenging ability against DPPH, ABTS+ and hydroxyl radical.

Thermal characteristic comparison of three-dimensional oscillating heat pipes with/without sintered copper particles inside flat-plate evaporator for concentrating photovoltaic cooling

In this study, a three-dimensional oscillating heat pipe with flat plate evaporator has been designed and experimentally tested for the cooling of concentrating photovoltaic cells. The startup performance, effective thermal resistance, and inclination angle effect on the thermal performance of oscillating heat pipes with/without sintered copper particles in the evaporator section were compared and evaluated. Experimental results showed that porous structures of sintered copper particles on the evaporator can significantly improve the vapor bubble generation and growth rate, and easily produce thin film evaporation to enhance latent heat transfer capacity. When charged with the same volume fraction of ethanol, the three-dimensional oscillating heat pipe with sintered copper particles always outperformed the one without them, especially at the horizontal orientation. The temperature of concentrating photovoltaic cells can be maintained below 57 °C at a corresponding heat flux of 5.88 W/cm2 when the input power is 40 W. In addition, a lowest thermal resistance of 0.145 K/W was achieved by the oscillating heat pipe with sintered copper particles at a filling ratio of 30% under an input power of 100 W. The three-dimensional oscillating heat pipe associated with outstanding heat transfer performance provides a promising candidate for concentrating photovoltaic cooling.