Mixture Of Glycerol Research Articles

23Na NMR T1 relaxation measurements as a probe for diffusion and dynamics of sodium ions in salt-glycerol mixtures.

Mixtures of sodium salts with oxygen-containing molecules are useful from the perspective of applications such as sodium ion batteries because they fill the gap between deep eutectic solvents and molten salt hydrates. In a previous work, the physical properties (such as diffusion coefficients, conductivity, viscosity, and glass transition temperature) of four salts, namely, Na2B4O7 · 10H2O, NaOAc · 3H2O, NaBr, and NaOAc, were measured with glycerol. Pulsed-field gradient (PFG) nuclear magnetic resonance (NMR) was also used to measure self-diffusion coefficients of 1H-bearing species. However, the technique was not able to measure diffusion of sodium ions due to the very fast NMR relaxation rate of such species, resulting in loss of the PFG NMR signal. In the current work, this study is expanded using 23Na T1 relaxation measurements which, under certain assumptions, can be translated into diffusion coefficients. Analysis of the physical properties is then correlated with self-diffusion coefficient measurements to elucidate information about structure and ionic mobility. It is shown that NaOAc · 3H2O, NaBr, and NaOAc fit models for ionic conductivity and diffusion, which are consistent with ionic liquids where charge transport is limited by ionic mobility rather than the number of charge carriers. The waters of hydration of NaOAc · 3H2O do not appear to form a separate phase but are instead strongly coordinated to the cation. In contrast, Na2B4O7 · 10H2O appears to form a water-rich phase with enhanced sodium mobility.

Production and stability of pigments by Talaromyces purpurogenus LC128689 in an alternating air phase-liquid phase cultivation system.

Effects of carbon source, nitrogen source, and alternatingly submerging the cells and exposing to gaseous oxygen on pigment production by Talaromyces purpurogenus LC128689, as well as pH, temperature, and UV stability of the pigments were investigated. Although fructose supported higher cell growth, a mixture of glucose and glycerol resulted in higher pigment production. Out of the organic and inorganic nitrogen sources investigated, peptone gave the highest cell concentration (7.2 ± 1.1g/L) and pigment production (p≤0 .05). The cells were then immobilized in loofa sponge and cultivated under alternating liquid phase-air phase (ALAP) system whereby the cells were alternatingly submerged and exposed to gaseous oxygen. After 20 days of cultivation, the concentrations of the red, orange, and yellow pigments were 30.15 AU500 nm , 15 AU460nm , and 6.25 AU400 nm , respectively. In comparison with submerged culture in flasks, the red and orange pigments were 100% and 50% higher (p≤0.05) in ALAP system. On the other hand, the yellow pigment was 100% higher in flask cultures than in ALAP. The three pigments were stable within a pH range of 2-12, retained more than 80% of their color intensity after autoclaving at (121°C and 1.0 atm) for 15min and exposure to UV (3uW/cm2 ) for 24h.

Ex-vivo confocal Raman microspectroscopy of porcine skin with 633/785-NM laser excitation and optical clearing with glycerol/water/DMSO solution

Confocal Raman microspectroscopy (CRM) with 633- and 785-nm excitation wavelengths combined with optical clearing (OC) technique was used for ex-vivo study of porcine skin in the Raman fingerprint region. The optical clearing has been performed on the skin samples by applying a mixture of glycerol and distilled water and a mixture of glycerol, distilled water and chemical penetration enhancer dimethyl sulfoxide (DMSO) during 30[Formula: see text]min and 60[Formula: see text]min of treatment. It was shown that the combined use of the optical clearing technique and CRM at 633[Formula: see text]nm allowed one to preserve the high probing depth, signal-to-noise ratio and spectral resolution simultaneously. Comparing the effect of different optical clearing agents on porcine skin showed that an optical clearing agent containing chemical penetration enhancer provides higher optical clearing efficiency. Also, an increase in treatment time allows to improve the optical clearing efficiency of both optical clearing agents. As a result of optical clearing, the detection of the amide-III spectral region indicating well-distinguishable structural differences between the type-I and type-IV collagens has been improved.

Foam glass derived from ferrochrome slag and waste container glass: Synthesis and extensive characterizations

Lately, energy-saving attempts in the construction and building materials industry have become more popular due to the diminishing natural resources. With this motivation, we investigated the first foam glass consisting of ferrochrome slag (FS) and waste soda-lime glass (SLG) for potential use as a heat insulation material. For this, FS and SLG waste materials were valorized as main constituents, whereas a mixture of water glass (WG) & glycerol (G) and a sufficient amount of water (W) was used as a foaming agent and a moisturizer in the batch mixture, respectively. The studied series was prepared with the composition of 20FS-70SLG-xG-(8-x)WG-2W where x: 2, 4, and 6 wt%. After that, three different process temperatures (800, 825, and 850 °C), two distinct heating rates (5 and 10 °C/min), and two discrete dwell times (15 and 30 min) paved the way for the synthesis of 36 different foam glass samples. Eventually, the fabricated 36 different samples were subjected to physical, thermal, mechanical, and microstructural evaluations. According to the findings, one can say that samples synthesized with a lower G-to-WG ratio, higher process temperature, lower heating rate, and higher dwell time have the best features. From the physical property determinations, we found out that bulk density (ρbulk) varied between 233 and 903 kg m−3 while the estimated porosity (P) ranged from 59.4 to 89.5%. Further, thermal conductivity (k) measurements demonstrated that the fabricated foam glass series provides lower values, namely from 0.038 to 0.130 W m−1 K−1. Besides, compressive strength (CS) values were found to be changing from 0.127 to 2.225 MPa. Microstructural evaluations via scanning electron microscopy (SEM) revealed the pore formations and the relevant alterations as a result of the different parameters. All in all, the authors concluded that a heat insulation material composed of nearly fully waste substances can effectively be produced.

Potential of the crude glycerol and citric acid mixture as a binder in medium-density fiberboard manufacturing

Potential of the crude glycerol and citric acid mixture as a binder in medium-density fiberboard manufacturing

Pool Boiling Heat Transfer Coefficients in Mixtures of Water and Glycerin

Heat transfer coefficients were investigated for saturated nucleate pool boiling of binary mixtures of water and glycerin at atmospheric pressure in a wide range of concentrations and heat fluxes. Mixtures with water mass fractions from 100% to 40% were boiled on a horizontal flat copper surface at heat fluxes from about 25 up to 270kWm−2. Experiments were carried out by static and dynamic method of measurement. Results of the static method show that the impact of mixture effects on heat transfer coefficient cannot be neglected and ideal heat transfer coefficient has to be corrected for all investigated concentrations and heat fluxes. Experimental data are correlated with the empirical correlation α=0.59q0.714+0.130ωw with mean relative error of 6%. Taking mixture effects into account, data are also successfully correlated with the combination of Stephan and Abdelsalam (1980) and Schlünder (1982) correlations with mean relative error of about 15%. Recommended coefficients of Schlünder correlation C0=1 and βL=2×10−4ms−1 were found to be acceptable for all investigated mixtures. The dynamic method was developed for fast measurement of heat transfer coefficients at continuous change of composition of boiling mixture. The dynamic method was tested for water–glycerin mixtures with water mass fractions from 70% down to 35%. Results of the dynamic method were found to be comparable with the static method. For water–glycerin mixtures with higher water mass fractions, precise temperature measurements are needed.

Morphological Properties of Cassava Film Influence by Plasticizers in Zinc-air Fuel Cell

The effect of plasticizers, glycerol, sorbitol, and sucrose on structural, mechanical, and chemical properties of cassava starch film has been investigated. The morphologies of cassava films were studied by the addition of a different type of plasticizer. Mixtures of cassava starch and distilled water with the combination of glycerol, sorbitol, sucrose as plasticizers. Dried films plasticized showed the results under a scanning electron microscope (SEM) as smooth film surfaces were observed in a mixture of glycerol, sorbitol, and sucrose because glycerol and sucrose are more hydrophilic than sorbitol, thus the presence of more hydroxyl groups (-OH groups) in the molecule, sorbitol interacted with water by hydrogen bonding resulting in less plasticizing effect compared to glycerol and sucrose. As a result, the presence of sorbitol as a plasticizer with glycerol and sucrose in cassava starch films provided a more compact and homogenous surface, improves the stability and flexibility of cassava starch films.

Effect of the Biodegradable Compounds Composition with Monoglycerides on Mechanical Properties

The purpose of this work is to improve the production technology of biodegradable hybrid compositions based on low-density polyethylene with thermoplastic starch and new plasticizer–distilled monoglyceride and determination of the composition effect on mechanical properties. Starch was plasticized with a mixture of glycerol and distilled monoglycerides, instead of the known sorbitol. This article describes methods for producing biodegradable hybrid composite films based on polyethylene and thermoplastic starches (corn, pea and rice) with a mass ratio of components, respectively, 40:60÷60:40 and their mechanical properties. Properties and structure of composite films are studied using test methods, rheological parameters, optical microscopy, and differential scanning calorimetry. The advantages of using monoglycerides as a plasticizer in thermoplastic starch/ polyethylene compositions have been demonstrated. Composites obtained using distilled monoglycerides and thermoplastic corn, pea and rice starch have been characterized by 62-81% higher values of critical stress and 62-93% elongation at rupture, compared with BHC containing sorbitol. The thickness of biodegradable hybrid composite films with monoglycerides is 55-86% less than that of films containing sorbitol in composition of thermoplastic starch. Higher elongation values at rupture and lower film thickness will ensure more effective destruction in environment and more cost-efficient use in packaging.

Valorisation of Olea europaea L. Olive Leaves through the Evaluation of Their Extracts: Antioxidant and Antimicrobial Activity.

Olea europaea L. leaves constitute a source of bioactive compounds with recognized benefits for both human health and technological purposes. In the present work, different extracts from olive leaves were obtained by the application of two extraction methods, Soxhlet and microwave-assisted extraction (MAE), and six solvents (distilled water, ethanolic and glycerol mixtures solvents). MAE was applied under 40, 60 and 80 °C for 3, 6.5 and 10 min. The effect of the extraction method, solvent and treatment factors (the latter in MAE) on the total phenol content (TPC), the antioxidant activity (AA) and the phenolic profile of the extracts were all evaluated. The extracts showed high values of TPC (up to 76.1 mg GAE/g DW) and AA (up to 78 mg TE/g DW), with oleuropein being the most predominant compound in all extracts. The Soxhlet extraction method exhibited better yields in TPC than in MAE, although both methods presented comparable AA values. The water MAE extract presented the strongest antimicrobial activity against five foodborne pathogens, with minimum inhibitory concentration (MIC) values ranging from 2.5 to 60 mg/mL. MAE water extract is proposed to be exploited in the food and nutraceutical industry in the frame of a sustainable economy.

The role of Escherichia coli FhlA transcriptional activator in generation of proton motive force and FO F1 -ATPase activity at pH 7.5.

Escherichia coli is able to utilize the mixture of carbon sources and produce molecular hydrogen (H2 ) via formate hydrogen lyase (FHL) complexes. In current work role of transcriptional activator of formate regulon FhlA in generation of fermentation end products and proton motive force, N'N'-dicyclohexylcarbodiimide (DCCD)-sensitive ATPase activity at 20 and 72 hr growth during utilization of mixture of glucose, glycerol, and formate were investigated. It was shown that in fhlA mutant specific growth rate was ~1.5 fold lower compared to wt, while addition of DCCD abolished the growth in fhlA but not in wt. Formate was not utilized in fhlA mutant but wt cells simultaneously utilized formate with glucose. Glycerol utilization started earlier (from 2hr) in fhlA than in wt. The DCCD-sensitive ATPase activity in wt cells membrane vesicles increased ~2 fold at 72 hr and was decreased 70% in fhlA. Addition of formate in the assays increased proton ATPase activity in wt and mutant strain. FhlA absence mainly affected the ΔpH but not ΔΨ component of Δp in the cells grown at 72 hr but not in 24 hr. The Δp in wt cells decreased from 24 to 72 hr of growth ~40 mV while in fhlA mutant it was stable. Taken together, it is suggested that FhlA regulates the concentration of fermentation end products and via influencing FO F1 -ATPase activity contributes to the proton motive force generation.

Co-assembly and Structure of Sodium Dodecylsulfate and other n-Alkyl Sulfates in Glycerol: n-Alkyl Sulfate-Glycerol Crystal Phase

Hypothesis.Following the observation of a microfibrillar phase in sodium dodecylsulfate (SDS)-glycerol mixtures, it is hypothesized that this phase is a crystalline structure containing SDS and glycerol, where the interaction between sulfate and glycerol layers mediates the co-assembly, which also could be universal for similar systems formed by n-alkyl sulfate homologues.Experiment.n-alkyl sulfate glycerol solutions were studied using a combination of optical microscopy, small- and wide-angle X-ray scattering (SAXS/WAXS). Time-resolved SAXS was employed to determine the phase formation in SDS-glycerol-water mixtures.Findings.The microfibrillar crystalline phase was reproduced in even-chained n-alkyl sulfates with a chain length between 12 and 18 carbon atoms, where the phase lamellar period increased uniformly with the alkyl chain length. Reconstruction of electron density profiles from the diffraction patterns allowed the lamellar structural motif of the phase, the glycerol location and stoichiometry to be determined. When SDS-glycerol-water mixtures with water concentration below 6 wt% are isothermally solidified at 20 °C, SDS-glycerol crystals and/or anhydrous SDS form, where the former is inhibited by the latter at higher water concentrations. The learnings from the SDS-glycerol phase formation allows new gels to be created, utilising the glycerol-sulfate motif generating microfibrils. This expands the knowledge of the applicable formulation space for SDS-water containing mixtures.

Correlation between the toroidal modes of an elastic sphere and the viscosity of liquids

Vibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing and also to investigate materials and mechanical properties. An analytical approach has been developed in this paper to accurately predict toroidal vibrations of an elastic nanosphere in water–glycerol mixture. The Maxwell and Kelvin–Voigt models are used to describe the viscoelasticity of this fluid. The influence of key parameters such as glycerol mass fraction, sphere radius, and angular mode number are studied. We demonstrate that the sphere radius plays a significant role on the quality factor. Results also highlight three behavior zones: viscous fluid, transition, and elastic solid. In addition, these investigations can serve as benchmark solution in design of liquid sensors.

Production, characterization and application of ternary phase diagrams for the purification of biodiesel produced from tropical almond seed oil

This study presents the application of ternary phase diagrams to tropical almond biodiesel components separation and purification at two temperatures. The seed oil was extracted mechanically and alkaline transesterified to produce biodiesel. The oil and biodiesel were characterized using standard methods. Tie lines and binodal solubility curve data were determined using modified cloud point titration procedures. Gas chromatographic method was employed in the analysis of the phase compositions. The mixture of biodiesel, methanol and glycerol were investigated at 20 °C, 30 °C and withdrawal times of 2 to 32 minutes at 2 minutes intervals. Distribution coefficient, K and solvent selectivity, S analysis were performed. Results obtained showed that S > 1 indicating the ability of methanol to promote phase separation and purification. K < 1 implying that there was lower quantities of methanol solubilized in the biodiesel phase. The ternary phase diagrams provided the means of predicting the components distribution.
 Keywords: Production, Characterization, Tropical Almond Biodiesel, Purification, Ternary Phase Diagram

Development of measurement system using online software for shear-horizontal surface acoustic wave sensor

In the medical field, point-of-care testing (POCT) is garnering attention. An online inspection system can be realized by combining POCT and the Internet. Herein, we report the performances of a measurement system developed using online software for a shear horizontal surface acoustic wave (SH-SAW) sensor. The developed SH-SAW measurement system does not require a phase detection circuit. The developed system can be used when the system is connected to the Internet. This enables an online measurement system that can be used “by anyone, at anytime, and anywhere.” In this study, we used samples of glycerol and water mixtures and then measured the amplitude ratio and phase difference of the SH-SAW sensor. The validity of the developed system is confirmed by comparing the measured results with theoretical values.

The in vitro ToxTracker and Aneugen Clastogen Evaluation extension assay as a tool in the assessment of relative genotoxic potential of e-liquids and their aerosols.

In vitro (geno)toxicity assessment of electronic vapour products (EVPs), relative to conventional cigarette, currently uses assays, including the micronucleus and Ames tests. Whilst informative on induction of a finite endpoint and relative risk posed by test articles, such assays could benefit from mechanistic supplementation. The ToxTracker and Aneugen Clastogen Evaluation analysis can indicate the activation of reporters associated with (geno)toxicity, including DNA damage, oxidative stress, the p53-related stress response and protein damage. Here, we tested for the different effects of a selection of neat e-liquids, EVP aerosols and Kentucky reference 1R6F cigarette smoke samples in the ToxTracker assay. The assay was initially validated to assess whether a mixture of e-liquid base components, propylene glycol (PG) and vegetable glycerine (VG) had interfering effects within the system. This was achieved by spiking three positive controls into the system with neat PG/VG or phosphate-buffered saline bubbled (bPBS) PG/VG aerosol (nicotine and flavour free). PG/VG did not greatly affect responses induced by the compounds. Next, when compared to cigarette smoke samples, neat e-liquids and bPBS aerosols (tobacco flavour; 1.6% freebase nicotine, 1.6% nicotine salt or 0% nicotine) exhibited reduced and less complex responses. Tested up to a 10% concentration, EVP aerosol bPBS did not induce any ToxTracker reporters. Neat e-liquids, tested up to 1%, induced oxidative stress reporters, thought to be due to their effects on osmolarity in vitro. E-liquid nicotine content did not affect responses induced. Additionally, spiking nicotine alone only induced an oxidative stress response at a supraphysiological level. In conclusion, the ToxTracker assay is a quick, informative screen for genotoxic potential and mechanisms of a variety of (compositionally complex) samples, derived from cigarettes and EVPs. This assay has the potential for future application in the assessment battery for next-generation (smoking alternative) products, including EVPs.

Electrical Conductivity of a Stretching Viscoelastic Filament.

Long polymeric chains highly stretched and aligned with the flow confer a strong mechanical anisotropy on a viscoelastic solution. The electrically-driven transport of free ions under such conditions is far from being understood. In this paper, we determine experimentally whether the above-mentioned deviation from isotropy affects the electric charge transport across the liquid. To this end, we measure the electrical conductivity in the flow (stretching) direction of the cylindrical liquid filament formed in the elasto-capillary thinning that arises during the breakup of a viscoelastic liquid bridge. First, we examine the behavior of monodisperse solutions of polyethylene oxide (PEO) in a mixture of glycerine and water. For all the concentrations and molecular weights considered, the filament conductivity remains practically the same as the isotropic conductivity measured under hydrostatic conditions. However, we observe a decrease in the electric current at the end of elasto-capillary regime which may partially be attributed to the reduction of the liquid conductivity. Then, we measure the conductivity of bidisperse solutions of PEO with very different molecular weights. In this case, a significant decrease in conductivity is observed as the filament radius decreases. This constitutes the first experimental evidence of ion mobility reduction in stretching viscoelastic filaments, a relevant effect in applications such as electrospinning.

E-Cigarette Flavoring Chemicals Induce Cytotoxicity in HepG2 Cells.

E-cigarette-related hospitalizations and deaths across the U.S. continue to increase. A high percentage of patients have elevated liver function tests indicative of systemic toxicity. This study was designed to determine the effect of e-cigarette chemicals on liver cell toxicity. HepG2 cells were exposed to flavoring chemicals (isoamyl acetate, vanillin, ethyl vanillin, ethyl maltol, l-menthol, and trans-cinnamaldehyde), propylene glycol, and vegetable glycerin mixtures, and cell viability was measured. Data revealed that vanillin, ethyl vanillin, and ethyl maltol decreased HepG2 cell viability; repeated exposure caused increased cytotoxicity relative to single exposure, consistent with the hypothesis that frequent vaping can cause hepatotoxicity.

Twisted Intramolecular Charge Transfer—Aggregation-Induced Emission Fluorogen with Polymer Encapsulation-Enhanced Near-Infrared Emission for Bioimaging

Fluorescence probes with strong near-infrared (NIR) emission and water solubility are considered useful visualization tools for localization marking as well as investigating cell migration and tran...

Effects of Glycerol and Propylene Glycol on Smoke Release of Heat-not-burn Tobacco Products

Glycerin and propylene glycol are the main components of the atomizing agent in heat-not-burn tobacco products (HnB), which affect the smoke release of HnB significantly. In this study, the roles of the glycerin and propylene glycol as the atomizing agent on smoke release of HnB were studied by using a fixed-bed reactor system. The effects of glycerin to propylene glycol ratio in the atomizing agent, and the content of atomizing agent in the HnB were investigated. Gas chromatography-mass spectrometer (GC-MS) was used to analyze the condensable components in the released smoke, and gas chromatography (GC) was used to analyze the gaseous products. The results showed that glycerol could promote the thermal cracking of tobacco and smoke release during pyrolysis. The amount of smoke was the largest when the glycerol ratio was 60%, meanwhile the nicotine content in the smoke was also the highest. When using the glycerin and propylene glycol mixture as the atomizing agent, the amount of smoke and concentration of nicotine and CO in the smoke were increased when the content of atomizing agent decreased in the HnB. The results indicated that the interactions between glycerin and propylene glycol, and the interactions between the atomizing agent and the tobacco were both existed during smoking, which could change the characteristics of the atomizing agent and the smoke release property of HnB.

Развитие женского гаметофита и эмбриогенез интродуцированных видов Picea А. Dietr. в таежной зоне (Карелия)

The aim of the research was to establish features in macrosporogenesis, macrogametogenesis, and embryogenesis in Picea species (native species P. abies and introduced species P. canadensis and P. pungens) in the Botanical Garden of Petrozavodsk State University (middle taiga subzone). To study the development of the generative sphere, shoots with generative buds and strobiles from the southwestern side of the crown were cut from 10 trees and fixed in a mixture of alcohol and glycerin. The development of the female gametophyte and the embryo was studied with constant preparations. Preparations for anatomical examination of the kidneys were prepared according to standard methods. In this case, double fixation in glutaraldehyde and osmium was used, wiring through alcohol and acetone, and encapsulation in epoxy resin. Sections with a thickness of about 1 μm were prepared on an ultramicrotome and stained in a 1% aqueous solution of methylene blue. Studies have established that in mid-May, the female gametophyte is still at a free stage, and by the beginning of June it already has a cellular structure. Embryogenesis begins in late July and ends in the second decade of August. In introduced species, various deviations are observed in the development of the female generative sphere and during embryogenesis. The main ones are the degeneration of the female gametophyte at the free-nuclear stage and the destruction of archegonia at the stage of proembryogenesis. For this reason, from 37 to 51% of the seeds of introducers are devoid of the embryo. The largest percentage of empty seeds and the most recent stages of the passage of the main stages of morphogenesis are observed in P. pungens. This indicates the least degree of adaptability of the generative sphere of this species of introducer to new conditions.