Glycol Solution Research Articles

3D structured capillary cell suspensions aided by aqueous two-phase systems.

We report a facile technique for 3D structuring of living cells by forming capillary cell suspensions based on an aqueous two-phase system (ATPS) of polyethylene glycol (PEG) and dextran (DEX) solutions. We demonstrate the formation of water-in-water (DEX-in-PEG) capillary bridges using concentrated suspensions of yeast cells which show enhanced rheological properties and distinctive 3D patterns. Capillary structured cell suspensions can potentially find applications in novel ways of 3D cell culturing, instant tissue engineering and many biomedical investigations.

Rotational and translational diffusion of biomolecules in complex liquids and HeLa cells.

Diffusive motion accompanies many physical and biological processes. The Stokes-Sutherland-Einstein relation for the translational diffusion coefficient, DT, agrees with experiments done in simple fluids but fails for complex fluids. Moreover, the interdependence between DT and rotational diffusion coefficient, DR, also deviates in complex fluids from the classical relation of DT/DR = 4r2/3 known in simple fluids. Makuch et al. Soft Matter, 2020, 16, 114-124 presented a generalization of the classical translational and rotational diffusion theory for complex fluids. In this work, we empirically verify this model based on simultaneous translational and rotational diffusion measurements. We use fluorescently stained cowpea chlorotic mottle virus (CCMV) particles as monodisperse probes and aqueous polyethylene glycol (PEG) solutions as a model complex fluid. The theory and experimental data obtained from fluorescence correlation spectroscopy (FCS) measurements agreed. Finally, we used the same model and analyzed the diffusion of Yo-Pro-1 stained large ribosomal subunits (LSU) in the cytoplasm and nucleus of living HeLa cells.

Effectiveness and safety of a 1L polyethylene glycol and ascorbic acid preparation for colonoscopy in routine clinical practice in Spain.

Large clinical trials and small real-world studies show that a 1L polyethylene glycol and ascorbic acid solution (1L PEG-ASC) is an effective and safe bowel preparation for colonoscopy. Here, the effectiveness and safety of 1L PEG-ASC was evaluated in a large cohort of patients in routine clinical practice in Spain. A sub-analysis was performed in an observational, multicenter, retrospective study assessing the effectiveness and safety of 1L PEG-ASC in adult patients undergoing a colonoscopy at 10 centers in Spain. Cleansing quality was assessed with the Boston Bowel Preparation Scale, scores ≥6 with all segmental scores ≥2 was considered adequate colon cleansing, high-quality was considered as cleansing ≥8 or =3 in the right colon. Polyp and adenoma detection rates, and adverse events were also assessed. Data was collected from 7160 patients: 48.3% males; mean age 58.0, 33.6% ≥65 years old. Adequate overall bowel cleansing was achieved in 95.6% of patients (95% CI 95.1%-96.0%), high quality cleansing in 74.4% (95% CI 73.4%-75.4%) and high-quality right colon cleansing in 66.0% (95% CI 64.9-67.1). The adequate overall cleansing rate was 97.0% with a split-dose and 94.0% with same-day regimen (P<0.0001), and high-quality right colon cleansing was 69.0% and 62.5% (P<0.0001), respectively. Colonoscopy was completed in 97.2% of cases. A multivariate regression analysis revealed that an overnight split-dose regimen and age <65 years were independent predictors of adequate bowel cleansing of the overall colon, age <65 years and female gender were independent predictors of HQ cleansing of the overall colon, and the three covariates were independent predictors of HQ cleansing of the right colon. At least one adverse event was experienced by 3.3% of participants, with nausea (1.5%) and vomiting (1.2%) being the most frequent. This sub-analysis confirmed 1L PEG-ASC to be an effective and safe bowel cleansing preparation in a real world setting in Spain.

Synergistic Effects of Ethylene Glycol Solution and Polycarboxylate Superplasticizer on the Hydration of Calcium Sulphoaluminate Cement at −10°C

Synergistic Effects of Ethylene Glycol Solution and Polycarboxylate Superplasticizer on the Hydration of Calcium Sulphoaluminate Cement at −10°C

A universal chemical approach to the growth of self-assembled vanadium dioxide nanostructures

Vanadium dioxide (VO2) nanocrystalline materials are of great interest as for modern electronics and photonics as well as for energy saving technologies. Nevertheless, there still remains a challenge to realize their controllable synthesis, as evidenced by the low rate of implantation of existing technologies into mass production. Here, a hydrothermal reaction in a water-ethylene glycol (EG) solution has been coupled with the post-deposition annealing, yielding a range of phase-pure vanadium dioxide nanostructures on single-crystal r-sapphire substrate. A directed change in the viscosity of the precursor solution by using a change in the EG : H2O ratio makes it possible to control the nucleation rate and thus form VO2 isolated nanocrystals, as well as their ordered ensembles with regular distribution and uniform films on the substrate. The obtained nanostructures were extensively characterized by Raman spectroscopy, scanning electron microscopy, atomic force microscopy, and transmission electron microscopy combined with energy-dispersive X-ray spectroscopy. Continuous VO2 nanostructures demonstrated a metal-insulator transition (MIT) with a jump in resistivity of about 103–104, as well as a giant terahertz (THz) modulation depth up to 86 % (in the range from 0.3 to 2.0 THz), which confirms their high-quality and the possibility of their use in the creation of functional electronic and THz optical devices.

Liquid-Vapor Interface of Aqueous Ethylene Glycol Solutions: A Molecular Dynamics Study.

While the organic constituent in an aqueous binary solution enriches its liquid-vapor (l-v) interface, the extent of enrichment can depend nonlinearly on its mole fraction. A microscopic quantification and rationalization of this behavior are crucial to understand the dependence of properties such as surface tension and evaporation rate of the solution on its composition. Extensive all-atom molecular dynamics simulations of aqueous ethylene glycol (EG) solutions show that the composition of the solution at the l-v interface deviates the most from that in the bulk solution at an EG mole fraction of 0.3. The population of EG molecules with their central C-C dihedral in the gauche conformation was found to be higher at the l-v interface than that in the bulk solution to facilitate the orientation of its hydrophobic methyl groups toward the vapor phase. Free energy calculations reveal that in dilute EG solutions, an EG molecule is most stable at the l-v interface. The behavior of vapor pressure in aqueous EG solutions is ideal and follows Raoult's law, while in contrast, the aqueous solution of dimethyl sulfoxide does not. A rationale for the same is provided through the orientational distribution of interfacial water molecules in the respective solutions.

Nanostructure-Based Solution Sensor Fabricated with p-CuOx/n-TiO2 Nanojunctions To Identify Species and Concentrations of Alcohol Molecules.

Chemiresistive sensors fabricated based on metal-oxide-semiconductors, the most widely used high-sensitivity sensor materials, are required for detecting target solutions and gases and identifying them with a high degree of accuracy. In this study, we used p-n nanojunctions and nanowire shapes for identifying alcohol solutions. The solution sensors fabricated based on CuOx nanowires with p-CuOx/n-TiO2 nanojunctions detected ethanol, ethylene glycol, and diethylene glycol solutions via DC voltage and electrochemical impedance measurements. The p-n nanojunctions affected the sensors' sensitivity in the diethylene glycol solution, and the nanowire surface areas affected the relaxation time in ethanol and ethylene glycol solutions. To identify alcohol solutions, principal component analysis was performed based on the relationship between the sensor information, such as the presence of p-n nanojunctions and nanowire surface areas, and the sensing performance. This analysis identified alcohol molecular species and predicted alcohol-solution concentrations in the 0.1-20 vol % range with a high degree of accuracy. The concept of using sensors with different surface conditions with respect to p-n nanojunctions and nanowire surface areas offers designs for metal-oxide-semiconductor sensors to identify various molecules in solution.

Planar light induced fluorescence quenching oxygen diffusivity measurement near the gas–liquid interface in aqueous glycerol and aqueous propylene glycol

Experimental diffusivity data for gases in liquid mixtures are still scarce. To measure the diffusivity of dissolved oxygen in aqueous solutions of glycerol and propylene glycol, a planar light induced fluorescence (PLIF) method has been employed. The experimental method developed allows the measurement of the concentration field near the gas–liquid interface. The results show an increased oxygen diffusivity for the aqueous glycerol solution compared to the aqueous propylene glycol solution, corresponding to the lower viscosity of the solvent. Interestingly, during the first few seconds of oxygen absorption, a reduced early diffusivity is found for both experiments compared to later times. The results are compared with selected correlations and available experimental values. In general, the results are in good agreement with the literature data found and the discrepancy between early and later diffusivity is discussed.

Evaluations of ethylene glycol and polyethylene glycol aqueous solutions using a hybrid sensor of surface plasmon resonance and quartz crystal microbalance

A hybrid sensor based on surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) was prepared. One of the electrodes of the QCM sensor had a grating structure to enable SPR excitation. The SPR property was investigated through the transmission of the visible-light spectrum. The theoretical calculation showed that the experimental values almost corresponded to the theoretical ones; this suggests that the transmitted light dips were due to SPR. In order to investigate the usefulness of this hybrid sensor, the characteristics of SPR and the oscillation frequency drops of QCM (ΔF QCM) were investigated for aqueous solutions of ethylene glycol and polyethylene glycols with various degrees of polymerization. The position and slope of the SPR dip wavelength and the ΔF QCM curves depended on the degree of polymerization, suggesting that the sensor can be used to evaluate a solution property and/or discriminate a solute material.

Effect of tebuconazole and azoxystrobin on the physiological parameters of wheat seedlings and their resistance to water stress

Strobilurin and triazole class fungicides are actively used in agriculture as part of dressers to protect plants from fungal disease. In addition, they have various physiological effects on plants, including increased resistance to adverse environmental factors. The combined effect of these fungicides under water stress is understudied. The present work aims to examine the individual and combined effects of tebuconazole and azoxystrobin on the growth characteristics of wheat and its resistance to water stress. The study used winter wheat (Triticum aestivum L. ) plants grown from seeds treated with tebuconazole (2 mg/50 g seeds) and azoxystrobin (4 mg/50 g seeds) suspensions separately or together. In order to create water stress, five-day seedlings were transferred to 20% polyethylene glycol solution (PEG 6000), with stability assessed at seven and nine days. Tebuconazole was found to have a retardant effect on shoots and stimulate root growth. Azoxystrobin inhibited shoot growth and particularly root growth. When used together, tebuconazole partially reduced azoxystrobin-induced root inhibition. Azoxystrobin increased the negative effect of water stress, while tebuconazole effectively protected the root system of seedlings, partially reducing the effect of azoxystrobin. The stimulation of root growth with tebuconazolewas concluded to play an important role in providing resistance of winter wheat to water stress and to have the potential for use in agriculture.

New Process for Na2CO3 Production from Na2SO4 Based on Modeling the Na2SO4-(NH4)2SO4-MEA-MEG-H2O System.

Alternative means for soda ash (Na2CO3) production from sodium sulfate (Na2SO4) are needed due to the intensive consumption of energy in the conventional Mirabilite-Solvay process (MSP). We demonstrate a new process to produce soda ash using sodium sulfate as a feed material. The new process relies on the antisolvent crystallization of unreacted Na2SO4 to separate it from soluble (NH4)2SO4 in a mixed monoethanolamine (MEA) and monoethylene glycol (MEG) solution. To develop the process, the solubilities of Na2SO4 and (NH4)2SO4 solids in aqueous mixed MEA-MEG solutions were first measured and then modeled using regressed paired-ion interactions from the electrolyte nonrandom two-liquid (E-NRTL) model. Anhydrous dense soda ash with a bulk density of up to 1146 kg/m3 was obtained when the concentrated Na2SO4 brines reacted with CO2 and NH3.

Solid-solid phase change fibers with enhanced energy storage density for temperature management

Solid-solid phase change fibers are advantageous for thermal management and latent heat storage, because they don't have the issue of liquid leakage facing those common ones that have a solid-liquid phase-transition. However, the relatively low heat density hinders such fibers from real applications. Herein, we report a strategy to fabricate solid-solid phase change fibers with much enhanced energy storage density, through coaxial wet spinning using thermoplastic polyurethane solution and polymerizable polyethylene glycol solution as outer spinning solution and inner spinning solution, respectively, followed by light-driven radical polymerization. The resulting fibers exhibited good flexibility and good tensile performances, with elongation at break and breaking strength of approximately 629.1 % and 3.8 MPa, respectively. Moreover, the fibers showed quite high heat density of 122.5 J/g, much higher than that of the previously reported phase change fibers with a solid-solid phase-transition, and high reusability, with heat density of 102.0 J/g preserved after 100 heating-cooling cycles. These attractive features make the fibers to be promising for wearable temperature management, energy harvesting and heat storage applications.

Electrodepostion of compact cadmium deposits in the non-aqueous ethylene glycol solution modified with ethanol

Using non-aqueous solvents for metal electrodeposition can suppress hydrogen evolution reactions, thereby preventing hydrogen embrittlement in metallic structural materials. Ethylene glycol, which has a large solubility for metal acetates, might be a good non-aqueous solvent candidate. However, its relatively high viscosity and poor wettability lead to forming loose metal deposits during the electrodeposition, which is not suitable for anti-corrosion applications. In this work, we modify the ethylene glycol solution by adding ethanol and systematically investigate the roles of ethanol concentration, deposition potential, and temperature on the physical properties of the solution, electrochemical behavior of cadmium deposition, and microstructure of the deposits. Our results show that adding ethanol significantly reduces the viscosity of the electrolyte and improves its interfacial wettability, which promotes the formation of compact and thick deposits.

An experimental study on the role of electrical conductivity in the steady cone-jet electrospray

In present work, the effect of the electrical conductivity on the steady cone-jet electrospray are experimentally investigated, where the operating diagram and the jet breakup instability are extensively examined. A hemispherical tube is employed as spraying nozzle severed as high electric potential electrode in a needle-plated electrode configuration compared to the common and sheathed tubes. The cone-jet electrospray is visualized by a high-resolution camera and extensively analyzed offline. The aqueous solution in ethanol, Diethyleneglycol (DEG) and Ethylene glycol (EG) are atomized with varied electrical conductivity under different high electric potentials and flowrates. Experimental results indicate that the cone-jet electrospray can operate in the certain ranges of operating parameter for all types of capillaries. The operating diagram for the hemispherical tube is significantly broader than other tubes because of various electric field strength distribution. The onset electric potential to determine a steady cone-jet electrospray gradually increases and the termination value also increases as the electrical conductivity increasing. The lower and upper flowrate to form a steady cone-jet electrospray also increase as the electrical conductivity increases. The jet breakup instability can transit from varicose to whipping due to low the reference flow rate as electrical conductivity increasing, which is agreement with theoretical analysis. In particular, for EG, the transition from whipping to similar micro-dripping is observed as the electrical conductivity increasing, while the transition also occurs as flowrate increases for EG with higher electrical conductivity. The increase in the electrical conductivity and flowrate elongates the cone due to EHD body force, which causes the electric field vary, further resulting in the difference in jet breakup instability. Moreover, the electrical conductivity also plays an important role in jet breakup length.

Approaching ratio as a guideline for substrate design of forward osmosis membranes

Forward osmosis (FO) has been proposed as an ecologically friendly and low carbon footprint technology for concentrating enriched lithium brine from the salt lake using freely available MgCl2 onsite as the draw. In this process, Li+ concentration is raised from a few hundred mg/L to 20-30 g/L (Li+) before precipitation of Li2CO3. To allow FO technology a wide margin in competing with other concentration technologies, it is highly desirable to develop a simple, low cost method to fabricate FO membrane. Besides, due to both feed and draw solutions being of high salinity, FO membranes should also have a defect-free polyamide (PA) separation layer and a low structural parameter (S) substrate. This paper presents a simple guideline called approaching ratio (α) to adjust the substrate pore morphology based on a ternary polysulfone (PSf)/N,N-dimethylacetamide (DMAc)/diethylene glycol (DEG) solution. The α ranging between 0 and 100 % is a metric measuring how close the solution is to the cloud point. The increase of α endows instant phase separation, resulting in the substrate with increased surface porosity and sponge-like structure. Pore connectivity is improved following an increase of α below a threshold value of 50 %. Water permeability dramatically increases from α = 0 % to α = 50 % and declines at above 50 % for forming the closed cellular pores at α = 80 %. The FO water flux shows a similar trend which was found to be closely related to the substrate pore interconnectivity. The FO membrane was applied in the lithium concentration process using saturated MgCl2 as the draw, the experimental results fit well with the FO model. The results demonstrate a simple, low-cost generic method to prepare FO membranes for applications with very high salinity feed and draw.

Optimization research on battery thermal management system based on PCM and mini-channel cooling plates

A phase change materials (PCM) coupled mini-channel cooling plates model was established for the optimization of the battery thermal management system (BTMS). Specific cooling strategies with different discharge rates of the battery were discussed. For a discharge rate of under 2C, using PCM can meet the heat dissipation needs. Particularly, for a discharge rate below 1.2C, external cooling was not necessary. For a discharge rate above 2C, active cooling should be added to compensate for the lack of heat storage of PCM. In the research of optimization structure, it was found that the scheme of four cooling plates and each cooling plate with two mini-channels was the most ideal in this research, which not only reduced the battery temperature efficiently but also maintained a good temperature uniformity of the battery. For the optimization parameters, the effect of the ethylene glycol solution temperature, ethylene glycol solution volume fraction and the start-up time of active cooling on the maximum temperature of the battery and the melting fraction of PCM were discussed. After the multi-factor parameters optimization by Response Surface Methodology, three optimization schemes were put forward, which could reduce the driving power consumption by 35% – 40%. The research could provide valuable information support and optimization suggestions for the design of BTMS.

A novel variable liquid-properties thermal network model for researching on thermodynamic characteristics of ethylene glycol piston pump

Due to the flame resistance and lubricity of ethylene glycol solution, an ethylene glycol piston pump can be used as motion sources for extreme operating conditions. In this paper, a novel variable liquid-properties thermal network model (VLTNM) is proposed to analyze the thermodynamic characteristics of piston pump. The VLTNM considers the interaction between the changes in properties of liquid passing through piston pump and the heat generated by motion, and calculates the heat transfer between solid and liquid through a thermal network. A numerical calculation model for VLTNM is established in MATLAB using simscape language, and the results show that the temperature rise of outlet liquid can be reduced by 10.36%, when the thermal conductivity of shell is doubled. The working pressure has a positive effect on temperature variation, which is more significant in high-temperature environments, while the volume fraction of ethylene glycol solution has a negative effect. Additionally, a high load helps to improve the efficiency of piston pump, while the temperature rise caused by high pressure can also reduce the efficiency. When the working pressure increases from 6 MPa to 10 MPa, the efficiency decline of piston pump increased by 1.12%. Besides, comparing the two models of variable and non-variable liquid properties, there is a significant deviation in steady temperature of outlet liquid. The deviation in low temperature is more prominent, with a deviation of 6.1% when the temperature of air is 10 °C. Finally, the predicted steady temperature by VLTNM is in good agreement with the experimental data in reference, with a prediction error of less than 2.01%.

Preparation of Ordered Nanostructures by Anodization of Ag Substrate with Depression Patterns

Nanostructures composed of Ag oxides are key materials with various potential applications such as sensors, catalysts, and batteries. We successfully fabricated nanohole array structures with an ordered arrangement of pores by anodizing a Ag substrate with a depression pattern in an ethylene glycol solution containing NH4F and KOH. Under these anodization conditions, each depression acts as a starting point for pore generation in the early stages of anodization. In addition, ordered nanopillar array structures were obtained by anodizing Ag substrates with depression patterns in ethylene glycol solution containing NH4F and CH3COONa. This is because the depressions formed by Ar ion beam irradiation act as masks during anodization, and the depressions remain during anodization, forming a nanopillar array structure. This is the first report on the fabrication of nanohole and nanopillar array structures by the anodization of a Ag substrate. In addition, this is the first report to show that ordered nanohole and nanopillar array structures can be fabricated by changing the electrolyte used for anodization. The Ag oxide nanostructures obtained by this process are expected to be applicable to various functional devices.

Separation of cobalt and nickel from ethylene glycol and glycerol feed solution in chloride media by non-aqueous solvent extraction with Cyphos IL 101

A non-aqueous solvent extraction (NASX) process for the separation of cobalt and nickel from ethylene glycol and glycerol/water feed solutions using the ionic liquid Cyphos IL 101 has been investigated. The use of undiluted Cyphos IL 101 was critically assessed and compared with solvent extraction systems in which toluene, p-cymene, Shellsol A150, and Shellsol GS190 were used as diluents. While the extraction of cobalt(II) chloride from aqueous solution was possible only at high chloride concentrations, extraction percentages of cobalt higher than 80 % were observed from ethylene glycol and glycerol/water feeds containing 0.8 mol·L-1 NaCl. Separation factors over 40,000 for cobalt and nickel could be achieved for extraction with undiluted Cyphos IL 101 from 2.4 mol·L-1 NaCl ethylene glycol and 1.6 mol·L-1 NaCl glycerol feeds. The distribution ratio of cobalt increased with increasing temperatures in both NASX systems. Studies on the mutual solubility showed that Cyphos IL 101 is highly soluble in ethylene glycol at 21 °C (i.e. phosphorus contents up to 432 mg∙L-1), but it turned out that impurities contributed for 400 mg∙L-1 to this value. On the other hand, only 87 mg∙L-1 of Cyphos IL 101 dissolved in glycerol at 21 °C. Finally, a conceptual flowsheet for the separation of cobalt and nickel by NASX is presented, including extraction, stripping, and recovery of the solvents.

Cryopreservation of rat embryos at all developmental stages by small-volume vitrification procedure and rapid warming in cryotubes

Intracellular ice formation during cryopreservation is lethal to the cell, including during warming. Here, we examined the effect of sample volume and warming rate on the cryopreservation success of 1-cell rat embryos based on successful development into blastocysts in vitro and to term in vivo following embryo transfer. Embryos were equilibrated in 5% propylene glycol solution for 10 min, held for 40 s at 0 °C in cryopreservation solution (5%PG + PEPeS), and cooled by immersion in liquid nitrogen. When 1-cell embryos were cryopreserved in a volume of 30–100 μL at a cooling rate of 5830–7160 °C/min and warmed at 35,480–49,400 °C/min by adding 1 mL of 0.3 M sucrose solution at 50 °C, 17.3–28.8% developed into blastocysts, compared with 57.0% of untreated embryos. However, when 1-cell embryos were cryopreserved in a smaller volume of 15 μl at 7950 °C/min and warmed at 68,850 °C/min, 58.8 ± 10.6% developed into blastocysts and 50.0 ± 7.4% developed to term, comparable to that of non-treated embryos (57.0 ± 5.4% and 51.4 ± 3.1%, respectively). Cryopreserved embryos at other developmental stages also showed high in vitro culture potential similar to that of the control. Using a conventional cryotube and a small-volume vitrification procedure with rapid warming, we achieved high levels of subsequent rat embryonic development at all developmental stages.