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The increased energy demand and decreasing fossil resources have driven the research community to look into a sustainable, green process to meet the energy demands. India being one of the top producers of sugarcane derived sucrose, and conversion of surplus sucrose to value chemicals is always an advantage. 5%Ni-15%Ce/TiO2 catalyst is found to produce high yield of 1,2-PDO (~ 74%) under very mild reaction condition of 180 °C, 30 bar H2 for 3-h reaction time. The characterization of the catalyst by using various physicochemical methods indicates the synergy between Ni-Ce bimetal which enhances the selective production of glycol. The low temperature and pressure requirement and the advantage of being the one-pot process will always attract the future scope of commercialization. [ABSTRACT FROM AUTHOR]

Fresh eucalyptus stems can be preserved via systemic absorption of glycerin, but the optimal rate of glycerin and its effect on foliage color and stem pliability during holding have not been well-described. We harvested stems of Eucalyptus pulverulenta ‘Baby Blue’ and treated them in solutions of 0% (control), 25%, 50%, and 75% glycerin:reverse-osmosis water for 2 weeks. Leaf greenness was measured nine times during this period; the change in stem weights and solution uptake were measured as well. Stem pliability was evaluated after 2 weeks in solution as well as 1 week after holding the stems dry. The 25% and 50% glycerin treatments increased stem weight, whereas the control and 75% treatments decreased stem weight. The glycerin treatments absorbed less than 50 mL solution per three stems during 2 weeks, whereas those in the control absorbed >270 mL water. The color of foliage was similar during the first 5 days in treatment solutions, but stems in 25% and 50% glycerin treatments were less green than those in the control and 75% treatments by day 6, and this trend continued. No difference occurred in stem pliability among treatments after 2 weeks in glycerin solutions; however, after 1 week of holding, the top 9 cm of stems in glycerin treatments were more pliable than those in the control. Based on these results, we recommend a rate of 25% glycerin to preserve eucalyptus foliage for use in botanical artistry.

To prevent frost damage in fruit trees, growers employ passive and active methods, and one of these second methods is the use of biostimulant compounds against abiotic stress. In this study, two trials were conducted to evaluate the effectiveness of a multi-attribute approach biostimulant—containing α-tocopherol, boron, and glycols, in peach ('UFO-4' cultivar) and almond ('Vairo' cultivar) trees. In a first trial, one-year-old shoots with flowers were collected after 24 h, 48 h, and 96 h of the biostimulant applications. Two different application rates of the product (1000 and 2000 cc ha−1) were tested and compared to an untreated control. In a second trial, one-year-old shoots with fruitlets were collected after 24 h of the biostimulant applications. In this case, only an application rate (2000 cc ha−1) was tested. In the two trials, the collected one-year-old shoots were subjected to different frost temperatures using a controlled environment chamber. The damage level was assessed by a morphological analysis of the flowers and fruitlets 96 h after each frost cycle simulation. The lethal temperatures (LT10, LT50, and LT90) of each treatment were calculated by probit analysis. The product applied 24 h and 48 h before the frost simulations significantly decreased the LT10 and LT50 in 1.5 °C in peach flowers, and 2.5 °C in almond flowers (a temperature reduction of 50% and 75%, respectively). These results were more consistent when the application volume was 2000 cc ha−1, instead of 1000 cc ha−1. Significant differences between treated and non-treated fruitlets were observed only in almond fruitlets, with LT10 and LT50 being 0.5 °C lower in treated fruitlets (20% reduction). In conclusion, the multi-attribute approach biostimulant applied 24 or 48 h before the frost reduced the mortality of peach and almond flowers, but its effectiveness to protect fruitlets after bloom was inconsistent. [ABSTRACT FROM AUTHOR]

Background Toxic alcohols are chemicals with common metabolic characteristics resulting in severe morbidities and mortalities. The current study aimed to assess the efficacy of six scoring systems: The Poison Severity Score (PSS), Acute Physiology and Chronic Health Evaluation (APACHE) II score, Sequential Organ Failure Assessment (SOFA) score, Rapid Acute Physiology Score (RAPS), Rapid Emergency Medicine Score (REMS), and Modified Early Warning Score (MEWS) in stratifying the patients exposed to toxic alcohol based on liability of organ failure, prolonged hospital stay, and need for an antidote. Methods A seven-year retrospective cross-sectional study was conducted using medical records of adult patients admitted to a poison control center. Results About 42.6% were complicated with adverse outcomes. Methanol was the worst toxic alcohol and the only cause of blindness and death. About 27.1% of methanol-exposed patients suffered from acute kidney injury, 15.3% suffered from hemodynamic instability and neurological dysfunction, and 8.5% suffered from respiratory failure. An APACHE II score above 8 was the best predictor of unfavorable outcomes, exhibiting the highest area under the curve (0.972), followed by the SOFA score. The APACHE II score was praised for being the best discriminator of an expected prolonged hospital stay. Yet, the simple scores, including RAPS and REMS, showed good performance as unfavorable outcome predictors with no significant variations to PSS, APACHE II score, and SOFA scores. Conclusion The current study concluded that though the APACHE II and SOFA scores were superior to others, the RAPS and REMS are good, simple, and effective alternatives, particularly when resources are restricted. [ABSTRACT FROM AUTHOR]

Glycerol is a key by product of the biodiesel extraction process. The rapid growth of biodiesel establishments will continue to result in glycerol oversupply. Purified glycerol can be used as an antifreeze in automotive radiators since it has a freezing point of −30 °C and a boiling temperature of 160 °C. Heat transfer by automotive radiators is important in optimizing engine fuel economy. The goal of this research is to employ purified bio glycerol as a heat transfer fluid and a coolant in vehicle radiators. The proposed water mixed bio glycerol convective heat transfer rate is experimentally compared to standard ethylene glycol. The rate of heat transfer by bio glycerol is determined by passing the fluid through an automobile radiator test apparatus. For this objective, an Automobile Radiator test rig is devised and built. Experiments with distilled water blended bio-glycerol in volume ratios of 50:50, 70:30, and 60:40 were carried out, and the test findings revealed that the 70:30 water bio glycerol volume ratio created a higher heat transfer rate when compared to the water ethylene glycol mixture.

This study explores the rheological and tribological behavior of water-based lubricants (WBLs) as potential alternatives for electric vehicle (EV) applications. As the transportation sector increasingly shifts towards EVs to reduce carbon emissions, the demand for efficient lubricants becomes critical. WBLs here are defined as fluids containing a minimum of 50 wt% water mixed with glycerol, ethylene glycol (MEG), polyethylene glycol (PEG), or one of two polyalkylene glycols (PAGs). Rheological properties were investigated and compared with traditional lubricating oils. Results demonstrate distinctive rheological characteristics in WBLs, with viscosity–temperature responses resembling traditional oils with lowered pressure–viscosity coefficients. Nevertheless, WBLs exhibit promising film-forming capabilities in highly loaded contacts. Additionally, in sliding contacts, WBLs generally display lower friction coefficients compared to traditional oils, with PEG exhibiting the lowest value near 0.1. These findings suggest that WBLs may offer advantages in reducing friction and energy loss in EV applications. Furthermore, sliding wear tests indicate low wear rates in WBLs such as PEG, PAG, and glycerol, supporting their potential as viable lubrication options. The study highlights the importance of high-pressure rheology and tribochemistry in wear mechanisms among the different lubricants. [ABSTRACT FROM AUTHOR]

The effect of glycol derivatives including ethylene glycol (EG), diethylene glycol (DEG), and triethylene glycol (TEG) has been investigated on the characterization Al2O3 coating of anodized 7075-T6 aluminum in 20% w/w sulfuric acid, current density 4 A/dm2, and time 50 min. The thickness and hardness of Al2O3 layer measured and characterized by X-ray diffraction patterns, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The Tafle plots of linear polarization method and electrochemical impedance spectroscopy technique used to investigate the resistance to corrosion Al2O3 layer. The results showed that the thickness, hardness, and resistance to corrosion of Al2O3 film are increased, respectively, 30, 42, and 40% in the presence of glycols (10% w/w). The ratio of dielectric constant (ε) to dynamic viscosity (η) of TEG, DEG, and EG, respectively, is 0.48, 0.89, and 2.28 that is due to improvement of anodized aluminum in the presence glycol derivatives as EG > DEG > TEG. [ABSTRACT FROM AUTHOR]

To prevent frost damage in fruit trees, growers employ passive and active methods, and one of these second methods is the use of biostimulant compounds against abiotic stress. In this study, two trials were conducted to evaluate the effectiveness of a multi-attribute approach biostimulant—containing α-tocopherol, boron, and glycols, in peach (‘UFO-4’ cultivar) and almond (‘Vairo’ cultivar) trees. In a first trial, one-year-old shoots with flowers were collected after 24 h, 48 h, and 96 h of the biostimulant applications. Two different application rates of the product (1000 and 2000 cc ha−1) were tested and compared to an untreated control. In a second trial, one-year-old shoots with fruitlets were collected after 24 h of the biostimulant applications. In this case, only an application rate (2000 cc ha−1) was tested. In the two trials, the collected one-year-old shoots were subjected to different frost temperatures using a controlled environment chamber. The damage level was assessed by a morphological analysis of the flowers and fruitlets 96 h after each frost cycle simulation. The lethal temperatures (LT10, LT50, and LT90) of each treatment were calculated by probit analysis. The product applied 24 h and 48 h before the frost simulations significantly decreased the LT10 and LT50 in 1.5 °C in peach flowers, and 2.5 °C in almond flowers (a temperature reduction of 50% and 75%, respectively). These results were more consistent when the application volume was 2000 cc ha−1, instead of 1000 cc ha−1. Significant differences between treated and non-treated fruitlets were observed only in almond fruitlets, with LT10 and LT50 being 0.5 °C lower in treated fruitlets (20% reduction). In conclusion, the multi-attribute approach biostimulant applied 24 or 48 h before the frost reduced the mortality of peach and almond flowers, but its effectiveness to protect fruitlets after bloom was inconsistent.

Determining the glycol type and concentration of an engine coolant is a useful analytical test for in-service testing laboratories to both identify the coolant type and determine whether the coolant is fit for its intended purpose. Too much glycol can result in poor heat transfer within the engine whereas too little glycol can increase the freeze point of the coolant. As such repeat testing over the lifespan of the coolant is requir ed to avoid potential problems and ensure the overall health of the cooling system. This paper details a GC method to rapidly separate ethylene and propylene glycol in under five minutes and determine the concentration of these glycols in percentage. Two preparation methods are detailed to demonstrate a simple 'dilute & shoot' preparation by diluting in deionised water (10-fold dilution) or isopropanol (100-fold dilution). [ABSTRACT FROM AUTHOR]

The DNPG, which consists of naphthalimides at terminal positions of pentaethylene glycol chain, was non covalently doped on nanoporous silica (SiO2) and has been used as fluorescent powder for imaging of latent fingerprints (LFPs) on porous and non‐porous surfaces. We have successfully demonstrated the application of DNPG@SiO2 fluorescent powder for visualization of level 1 (indexing), level 2 (minutiae points) and level 3 (sweat pores). We also attempted to establish the identity of the subject (person) in case studies on 12 subjects. The CIE‐1931 coordinates (x,y) of 0.2, 0.3 of DNPG showed green colour with 49.4 % purity and it possessed low cytotoxicity (IC50=139.5 uM). [ABSTRACT FROM AUTHOR]

An in-depth experimental study of the matrix effect of antifreeze (ethylene glycol) and water contamination of engine oil through FT-IR spectroscopy. With a comparison of the percent by volume concentration of contaminated fresh 15W-40 engine oil, there appeared to be a noticeable reduction in the O–H stretching signal in the infrared spectrum when ethylene glycol based antifreeze was included as a contaminant. The contaminants of distilled water, a 50/50 mixture of water and commercial ethylene glycol antifreeze, and straight ethylene glycol antifreeze were compared and a signal reduction in the O–H stretch was clearly evident when glycol was present. Doubling the volume of the 50/50 mixture as compared to water alone still resulted in a weaker O–H stretching signal. The possibility that this signal reduction was due to the larger ethylene glycol molecule having fewer O–H bonds in a given sample size was eliminated by comparing samples with the same number of O–H bonds per unit volume. The strong hydrogen bonding between that of water and glycol appeared to reduce the O–H stretching signal, even after comparing the different sample types at concentrations with the same number of O–H bonds per unit volume. Tukey’s highly significant difference was used to show that samples of the 50/50 mixture and straight glycol were not reliably distinguishable from one another when comparing the same number of O–H bonds per unit volume but readily distinguishable from that of water as the lone contaminant.

In this study, ramie fiber was used as the biomass material to prepare carboxymethyl cellulose (CMC). Additionally, the films were prepared by casting method using the ramie-based CMC, and the glycol was added as a plasticizer to overcome the fragility of the films. The films were extensively characterized using FT-IR, XRD, and TG&DSC. Moreover, the physicochemical characteristics and tensile properties of the CMC films were also evaluated. It was demonstrated that the CMC films prepared from ramie fiber with good film performances and better tensile properties which are suitable for packaging applications. This study provides a new way for value-added ramie fiber.

Injection wells for carbon capture and storage are made of iron casings supported by cement. Cement can transform into calcium carbonate and iron into iron oxide. Thus, these wells are subject to corrosion. Monoethylene glycol (MEG), used for hydrate prevention and natural gas dehydration, can adsorb both to calcium carbonate and iron oxide. As a first step towards an atomistic understanding of effects caused by adsorbed MEG, molecular dynamics simulations were applied to estimate free energy changes to hydronium and bicarbonate as MEG was adsorbed to the surface. We found that the global free energy minimum of both hydronium and bicarbonate was moved closer to the surfaces, due to adsorbed MEG, which may be caused by MEG replacing water molecules within the first water layers. This could have an effect on chemical reactions involving hydronium and bicarbonate. Minima in the free energy profiles other than the global one was found to originate from adsorbed water combined with interactions from the surfaces. [ABSTRACT FROM AUTHOR]

ABSTRACT Purpose: To explore the role and mechanism of curcumin (Cur) in reducing oxidative stress damage in rats with nephrolithiasis induced by ethylene glycol (EG). Methods: Thirty male rats were divided into normal control, model, positive (10% potassium citrate), Cur-10 (10 mg/kg curcumin) and Cur-20 (20 mg/kg curcumin) groups. Results: The results of kidney tissue section stained by hematoxylin-eosin and von Kossa showed that curcumin treatment can inhibit the formation of kidney stones. The biochemical test results showed that the urea (Ur), creatinine (Cr), uric acid (UA), inorganic phosphorus and Ca2+ concentrations in urine decreased after being treated with curcumin. There were significant differences between different doses of curcumin (P < 0.05). Compared with the Cur-10 group, Cur-20 had a more significant inhibitory effect on malondialdehyde (MDA) (P < 0.05). In addition, reverse transcription polymerase chain reaction (PCR) detection and immunohistochemical results indicated that the osteopontin (OPN) in the kidney was significantly reduced after curcumin treatment. Conclusions: Curcumin could reduce the oxidative stress damage caused by EG-induced kidney stones.

The present study aimed to investigate the effects of different antifreeze protectants on the preservation of Hu sheep semen at 4 °C. The semen was diluted with Tris extender at room temperature, supplemented with dimethyl sulfoxide (DMSO) (0, 0.1%, 0.2%, 0.3%, 0.4% and 0.5%), glycerol (1.5%, 3.0%, 4.5% and 6.0%), glycol (2.50%, 5.00%, 7.50% and 10.00%), skimmed milk powder (SMP) (0.50%, 1.50%, 2.50% and 3.00%), soy lecithin (SL, 0.15%, 0.30%, 0.45% and 0.60%) and five optimal concentrations of antifreeze protectants (0.4% DMSO, 4.5% glycerol, 7.5% glycol, 1.5% SMP and 0.15% SL), and stored at 4 °C refrigerator. Spermatozoa motility parameters (spermatozoa viability, spermatozoa progressive motility, straight line velocity (VSL), curvilinear velocity (VCL) and average path velocity (VAP)) were evaluated during the preservation of semen. The addition of antifreeze protectants, especially the 0.4% DMSO, 4.5% glycerol, 7.50% glycol, 1.50% SMP and 0.15% SL exerted the best effects on spermatozoa viability and progressive motility compared to the spermatozoa without antifreeze protectants (control group). In the experiment of antifreeze protective agents with the optimal concentration, the spermatozoa viability and progressive motility of 1.5% SMP were significantly higher than those of other antifreeze groups during storage. In conclusion, the addition of 1.5% SMP to semen spermatozoa preserved at 4 °C refrigerator can most effectively enhance the semen preservation quality compared to the other optimal concentration of antifreeze protectant groups. [ABSTRACT FROM AUTHOR]

A computational investigation of the aerobic oxidative C–C bond cleavage reaction of glycol catalyzed by an Anderson-type heteropolyanion HPA [IMo6O24]5− in the presence of acetonitrile as solvent has been performed at the WB97XD/6-31G(d,p)/lanl2dz level. Two reaction pathways have been identified. The catalytic cycle of each pathway consists of three steps: oxidation cleavage of a glycol molecule by the HPA, oxidation of the HPA by one dioxygen molecule, and, finally, oxidation of a second glycol and regeneration of the catalyst. These reaction pathways have been thoroughly investigated in terms of energetic, natural bond orbital (NBO), natural charges, and geometrical parameters. It is found that (i) even though the top oxygen atoms of the Anderson heteropolyanion are not the most negatively charged ones, they are more likely to react with the diol hydroxyl groups, (ii) a direct relationship between the presence of the iodine ion I(VII) and the studied oxidation reaction could not be identified, and (iii) in terms of energy, the transfer of the two hydrogen atoms is the most energetic step. [ABSTRACT FROM AUTHOR]

A computational investigation of the aerobic oxidative C–C bond cleavage reaction of glycol catalyzed by an Anderson-type heteropolyanion HPA [IMo6O24]5− in the presence of acetonitrile as solvent has been performed at the WB97XD/6-31G(d,p)/lanl2dz level. Two reaction pathways have been identified. The catalytic cycle of each pathway consists of three steps: oxidation cleavage of a glycol molecule by the HPA, oxidation of the HPA by one dioxygen molecule, and, finally, oxidation of a second glycol and regeneration of the catalyst. These reaction pathways have been thoroughly investigated in terms of energetic, natural bond orbital (NBO), natural charges, and geometrical parameters. It is found that (i) even though the top oxygen atoms of the Anderson heteropolyanion are not the most negatively charged ones, they are more likely to react with the diol hydroxyl groups, (ii) a direct relationship between the presence of the iodine ion I(VII) and the studied oxidation reaction could not be identified, and (iii) in terms of energy, the transfer of the two hydrogen atoms is the most energetic step. [ABSTRACT FROM AUTHOR]

This paper describes the development of a method of catalytic polymerization that was then applied to synthesize sulfate-based oligomers from sulfamide. Two molecules, copper triflate and copper acetate, catalyzed the formation of oligomers with diol monomers. Two oligomers were identified as products of the reactions. Oligomers with sulfate incorporated in the backbone proved to have an ability for ion diffusion. When the oligomers were doped with lithium salt, anion transportation was predominant, as shown by solid-state NMR. The lithium ion was found to be strongly bonded to the backbone, while the anion was highly mobile. To corroborate this finding, we conducted molecular dynamics (MD) simulations, which revealed the structural characteristics and static properties of two electrolytes containing LiTFSI and two different polyethylene oxide oligomers. Interactions between the anion and cation were analyzed through computation of the radial distribution function (RDF) and the spatial distribution function (SDF). Our findings indicate that while the anion presents weak interactions with the polymer chain, the cation interacts strongly with the oligomer backbone. [Display omitted] • Synthesis of sulfate-based oligomers from sulfamide. • Copper-based catalysts promote formation of oligomers. • Oligomers with sulfate incorporated in the backbone prove to have an ability for ion diffusion. • Anion transportation is predominant, as shown by solid NMR. • Molecular dynamics (MD) simulations reveal that cation interacts strongly with the oligomer backbone. [ABSTRACT FROM AUTHOR]

An in-depth experimental study of the matrix effect of antifreeze (ethylene glycol) and water contamination of engine oil through FT-IR spectroscopy. With a comparison of the percent by volume concentration of contaminated fresh 15W-40 engine oil, there appeared to be a noticeable reduction in the O–H stretching signal in the infrared spectrum when ethylene glycol based antifreeze was included as a contaminant. The contaminants of distilled water, a 50/50 mixture of water and commercial ethylene glycol antifreeze, and straight ethylene glycol antifreeze were compared and a signal reduction in the O–H stretch was clearly evident when glycol was present. Doubling the volume of the 50/50 mixture as compared to water alone still resulted in a weaker O–H stretching signal. The possibility that this signal reduction was due to the larger ethylene glycol molecule having fewer O–H bonds in a given sample size was eliminated by comparing samples with the same number of O–H bonds per unit volume. The strong hydrogen bonding between that of water and glycol appeared to reduce the O–H stretching signal, even after comparing the different sample types at concentrations with the same number of O–H bonds per unit volume. Tukey's highly significant difference was used to show that samples of the 50/50 mixture and straight glycol were not reliably distinguishable from one another when comparing the same number of O–H bonds per unit volume but readily distinguishable from that of water as the lone contaminant. [ABSTRACT FROM AUTHOR]

The scope of the present study was to prepare fully bio-based unsaturated polyester resins (UPRs) with comparable properties to the commercial formulations. The focus was set on the determination of the optimal prepolymer formulation using the same set of diacids (itaconic and succinic acid) and different diols (propylene glycol, isosorbide and neopentyl glycol) or its equimolar mixtures, keeping the fixed molar ratio of 1:1:2.1 in all feed compositions. Instead of commonly used styrene, bio-based dimethyl itaconate was used as a reactive diluent (RD). The rheology of the obtained resins was studied in detail. The effect of the used diol on structural (FTIR), thermal (DSC), thermomechanical (DMA), and mechanical (tensile) properties was explained. The properties of UPRs were found to be highly dependent on the diol used in the prepolymer formulation. The UPR with an equimolar ratio of propylene glycol and neopentyl glycol was shown to be the most promising candidate to compete with the commercial petroleum-based resins. [ABSTRACT FROM AUTHOR]

While newer heater-cooler technologies using ethylene glycol-based (GB) solutions during cardiothoracic surgery have become commercially available, there is a paucity of clinical data describing their effectiveness during cardiopulmonary bypass (CPB) support. This analysis aimed to compare clinical characteristics and procedural outcomes using water-based (WB) and GB heater-cooler systems.A retrospective analysis was performed on consecutive adult patients undergoing CPB from June to October 2022 comparing WB or GB groups. The primary outcome was a composite of operative death or major morbidity. Secondary endpoints included transfusion requirements on CPB, patient cooling and warming rates, and vasoactive-inotropic scores (VIS) at case completion. P-control charts were used to monitor the weekly incidence of the composite outcome. A sub-analysis was performed to evaluate the primary outcome for cardiac surgery cases indexed by the Society of Thoracic Surgeons (STS).There were 167 patients included for analysis; 87 (52.1%) underwent CPB with a WB system and 80 (47.9%) with a GB system. GB procedure subjects were younger (p = .01), experienced longer CPB times (p = .034), and were more likely to receive thoracic transplant or aortic surgery (p = 0.015). The composite outcome of operative mortality or major morbidity occurred in 29.9% and 24% of the WB and GB groups, respectively (p = .372). P-control charts indicated a weekly mean incidence of 30% during WB practice, which decreased to 24% with GB practice. Among 106 STS-indexed cardiac surgery cases, mean composite outcome incidence decreased from 19% to 6% following our GB transition. Additionally, cooling, and warming rates indexed to patient BSA and VIS at case completion were not significantly different.Our analysis demonstrated a safe transition from WB to GB heater-cooler technologies in our practice. This early analysis suggests that GB heater coolers may be safely adopted to mitigate the risks of nontuberculous mycobacterium infections for cardiac surgical patients. [ABSTRACT FROM AUTHOR]

The lack of a standard experimental procedure to determine thermal conductivity of fluids is noticeable in heat transfer processes from practical and fundamental perspectives. Since a wide variety of techniques have been used, reported literature data have huge discrepancies. A common practice is using manufactured thermal conductivity meters for nanofluids, which can standardize the measurements but are also somewhat inaccurate. In this study, a new methodology to perform reliable measurements with a recent commercial transient hot-wire device is introduced. Accordingly, some extensively studied fluids in the literature (water, ethylene glycol, ethylene glycol:water mixture 50:50 vol%, propylene glycol, and n-tetradecane) covering the range 0.100 to 0.700 W m−1 K−1 were used to check the device in the temperature range 283.15 to 333.15 K. Deviations between the collected data and the theoretical model, and repeatabilities and deviations between reported and literature values, were analyzed. Systematic deviations in raw data were found, and a correction factor depending on the mean thermal conductivity was proposed to operate with nanofluids. Considering all tested effects, the expanded (k = 2) uncertainty of the device was set as 5%. This proposed methodology was also checked with n-hexadecane and magnesium-oxide-based n-tetradecane nanofluids. [ABSTRACT FROM AUTHOR]

Antonio Afonso de Miranda Neto,1 Diogo Turiani Hourneaux de Moura,1,2 Kelly E Hathorn,2 Francisco Tustumi,3 Eduardo Guimarães Hourneaux de Moura,1 Igor Braga Ribeiro1 1Gastrointestinal Endoscopy Unit, Hospital Das Clínicas, University of São Paulo School of Medicine, São Paulo, Brazil; 2Division of Gasteoenterology, Hepatology and Endoscopy – Brigham and Women´s Hospital – Harvard Medical School, Boston, MA, USA; 3Gastrointestinal Surgery Unit, Hospital Das Clínicas, University of São Paulo School of Medicine, São Paulo, BrazilCorrespondence: Igor Braga RibeiroGastrointestinal Endoscopy Unit, Hospital Das Clínicas, University of São Paulo School of Medicine, São Paulo, BrazilTel +5592981377788Email igorbraga1@gmail.comBackground: Colonoscopy is the gold standard exam for evaluation of colonic abnormalities and for screening and surveillance for colorectal cancer. However, the efficacy of colonoscopy is dependent on the quality of the pre-colonoscopy bowel preparation. Polyethylene glycol (PEG) and sodium picosulfate/magnesium citrate (SPMC) have emerged as two of the most commonly used bowel preparation agents. We conducted an evidence-based review of current evidence to further investigate the efficacy and patient tolerability of split-dose SPMC oral solution compared to PEG solution for colonoscopy bowel preparation.Methods: A systematic search was performed using Pubmed (MEDLINE), Web of Science, EMBASE, and Cochran Central Register of Controlled Trials databases. All studies on split-dose bowel preparation with SPMC and PEG were reviewed. Relevant studies regarding colonoscopy and bowel preparations were also included. Randomized controlled trials were prioritized due to the high quality of evidence.Results: Eight randomized controlled trials were included. Split-dose SPMC and PEG were associated with similar results for adequacy of bowel preparation. Split-dose SPMC was associated with increased patient tolerability and compliance.Conclusion: Split-dose SPMC and PEG are both adequate and safe for bowel preparation for outpatient colonoscopy, with split-dose SPMC being more tolerable for patients. Additional RCTs comparing these and other bowel preparation solutions are necessary to further investigate quality of bowel preparation, patient preference, and cost-effectiveness of the various options.Keywords: colonoscopy, bowel, polyethylene, glycol, sodium, picosulfate, magnesium, citrate, PEG, SPMC, tolerability, adenoma

Abstract Growing demand for oil and gas has driven drilling activities to deep formations and complex well structures. Drilling fluid must be able to maintain wellbore integrity and thermal stability over extended drilling time. Besides, drilling fluid should produce high rate of penetration (ROP) and low damage to formation rock. Glycol mud satisfies these criteria thanks to its unique cloud point phenomenon. When temperature exceeds cloud point temperature, glycol starts precipitate from mud by forming micelles, coats the rock surface, and plugs the small fractures in rocks. As a result, the flow of mud into rocks is restricted and wellbore stability is improved. This paper surveys more than 40 wells that were drilled with glycol mud. Field cases reported good wellbore integrity, thermal stability, high ROP, and low formation damage. Glycol mud is an excellent choice for battling well instability and high temperatures.

The review is devoted to noncyclic analogs of crown ethers (podands) containing an oxyethylene spacer and heterocyclic fragments at one or both of its ends. The paper considers publications on the methods of obtaining and properties of podands for the 2010–2021 period. [ABSTRACT FROM AUTHOR]

Solution behavior of two commercially used polyether glycols with poly(oxyethylene) (PEO)-poly (oxypropylene) (PPO)-poly(oxyethylene) (PEO) triblock composition--Diol (linear) and Triol (star-like)--was studied, concerning the concentration and temperature effects until the cloud point (CP). 2-(2-butoxyetoxy) ethanol (DB) increased their miscibility with water. The structural study was performed with 25% DB in water, which produced isotropic solutions at room temperature at all polymer concentrations. Micelle's formation was only observed above 40% of polymer, when reversed micelles were formed. The solvent nuclei of the reversed micelles increased with increasing polymer concentrations, caused by dehydration of the PPO chains, then decreased at further higher concentrations, with completely dehydrated hydro-phobic chains. When CP is reached, the solvent nuclei are separated by large polymer domains, without phase separation. Neither ordered nor gel phase was formed, probably due to a combination of high miscibility and short hydrophobic segments. The study was performed by Small-Angle X-ray scattering (SAXS) and complemented by Fourier-transformed infrared spectroscopy (FTIR) and dynamic light scattering (DLS). The main contribution of this work is based on the fact that the knowledge of the solubility behavior of Diol and Triol, by changing the solvent or temperature, opens up new possibilities of their use to phase separation processes in industrial applications and delivery systems. Moreover, the elucidation of mechanisms of solubility allows for the design of novel polyether glycols with tailored solution behavior for efficient performance in its target use. All applications rely on their solution behavior and can be benefited from the present results. [ABSTRACT FROM AUTHOR]

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Cotton stalk rich in carbohydrates can widely be hydrolyzed and saccharified to produce biofuels and biochemicals. However, the dense and complex network structure makes it difficult to be hydrolyzed in normal cases. In this work, the cotton stalk was pretreated by ethylene glycol and ferric chloride, and subsequently enzymatic hydrolyzed to fermentable sugars for the production of value-added products. An orthogonal experiment was also carried out to optimize the pretreatment conditions, including the ferric chloride concentration, solid/liquid ratio, reaction temperature, and reaction time. Results showed that the influencing factors on the hemicellulose and lignin removal of the cotton stalk were ranked in order of the ferric chloride concentration > solid/liquid ratio > reaction temperature > reaction time. The optimal conditions for the removal of lignin and hemicellulose were achieved, where 0.1 mol/L ferric chloride, 90 %(v/v) ethylene glycol, solid/liquid ratio of 1:15 (w/v), reaction temperature 160 °C, reaction time 20 min with 79.7% cellulose remaining, while 85.7% lignin and 88.9% hemicellulose removal, and cellulose content increased by 133.0%, hemicellulose and lignin content decreased by 67.2% and 58.0%, respectively. In addition, the structure and physical properties of the original and pretreated cotton stalk were characterized by N2-adsorption desorption (BET), X-ray diffraction (XRD), and Thermogravimetric analysis (TGA). Experimental results indicated that the specific surface area and pore volume increased approximately by 420.8% and 450.0%, respectively, compared with the original one, particularly that the pore size rose to 1.7nm. The increase of specific surface area, pore volume, and size greatly contributed to the enzyme accessibility to lignocelluloses. The crystallinity of pretreated cotton stalk also increased by 9.5%, compared with the original one. The removal of amorphous portion, hemicellulose, and lignin led only to the exposure of inner crystalline cellulose, thereby to fully access to cellulase for hydrolysis. The weight loss below 400 °C was 63% for the original stalk, and 89% for the pretreated residue in the TGA test, respectively, indicating that the removal of lignin effectively made cotton stalk less thermally stable after pretreatment. The enzymatic hydrolysis of pretreated stalks was conducted in a constant temperature shaker, where the cellulase loading of 8.3 FPU/g-dry substrate, substrate concentration of 5% (w/v), pH 4.8, temperature 50 °C, and the rotary speed of 150 rpm. It was found that the concentration of ferric chloride posed a significant effect on the enzymatic hydrolysis, compared with solid/liquid ratio, reaction temperature, and time. The glucose yield reached the highest (88.5%) after 48 h from the sample pretreated under the optimal conditions. Furthermore, the cellulose in the pretreated cotton stalk was completely converted to glucose at the hydrolysis time of 72 h, and cellulase loading of 8.3 FPU/g. The glucose yield increased by 7.6 times than before. Consequently, the ethylene glycol and ferric chloride effectively removed the lignin and hemicellulose, while remained cellulose to promote hydrolysis efficiency. Longer hydrolysis time and enzyme loading can also enhance the enzymatic hydrolysis for cotton stalk pretreatment. [ABSTRACT FROM AUTHOR]

The combination of solid and liquid sorption media for thermal energy storage has been explored in order to improve heat flow as well as storage capacity with respect to the incomplete space-filling of closely packed solid sorbents. Three scenarios were elucidated from which in two cases the liquid/solid combinations perform worse than the neat liquid or solid and a third scenario where the combination performs better than the separate sorbents. We identified a mixture of zeolite 13XBF with tripropylene glycol as an example for such a superior combination showing a similar adsorption curve over time as the pure zeolite or glycol. After complete saturation of the zeolite in the mixture, glycol continues to absorb water, thereby increasing the overall capacity of the system. We identified a low direct attractive interaction (dipolar and dispersive) of the liquid sorbent (tripropylene glycol) with the solid sorbent (zeolite 13XBF) as a prerequisite for improved performance.

An up-flow anaerobic sludge bed (UASB) reactor was operated for five months to treat domestic wastewater contaminated by propylene glycol -main component of Type 2 aircraft deicing fluid (ADF)- at threshold ratio based on optimization study with batch reactors [i.e., operated at externally included ADF = 0.83–4.20%]. Biogas yields up to ~0.4 m3/kg CODinfluent was achieved, however drastically reduced along with total chemical oxygen demand (tCOD) removal at ADF>1.20% and indicated strong inhibition. Hence, the UASB reactor was fed at ADF = 1.05% [tCODinfluent = 8930 ± 2100 mg/L] and yielded >80% tCOD removal on average. Next generation sequencing (NGS) findings also revealed that Firmicutes and Bacteroidetes had the highest ratios of relative abundances in biomass sample taken at the last operating day; hence co-existence of these phyla played significant role in glycol removal with Synergistetes and Thermotogae bacteria whereas Methanobacterium and Methanoculleus archaea increased remarkably.

With the aim to prepare asymmetric acetylenic γ-glycols, the reactions of 1-(2-ethoxyethyl)piperidin-4-one with propargyl alcohol were studied and the reaction conditions were optimized to reach satisfactory yields of the target glycols. Some transformations of the γ-glycols were studied. It was found that the reaction of 1-(2-ethoxyethyl)-4-(3-hydroxyprop-1-yn-1-yl)piperidin-4-ol with ethyl bromide involves exclusively the OH group on the quaternary carbon atom to form a monoethyl ether, and the mercury-catalyzed hydration involves cyclization with the elimination of a water molecule from the keto glycol moiety, leading to a spiroketone. It was shown that the catalytic reduction of 1-(2-ethoxyethyl)-4-[2-(1-hydroxycyclohexyl)ethynyl]piperidin-4-ol at atmospheric pressure produces a mixture of a saturated and an unsaturated products in a 1 : 2 ratio. Quantum-chemical calculations of the stable conformers of the synthesized asymmetric acetylenic γ-glycols were performed by the RHF/STO-3G method with geometry optimization using Gaussian 09 software. [ABSTRACT FROM AUTHOR]

Background: Colonoscopy is the gold standard exam for evaluation of colonic abnormalities and for screening and surveillance for colorectal cancer. However, the efficacy of colonoscopy is dependent on the quality of the pre-colonoscopy bowel preparation. Polyethylene glycol (PEG) and sodium picosulfate/magnesium citrate (SPMC) have emerged as two of the most commonly used bowel preparation agents. We conducted an evidence-based review of current evidence to further investigate the efficacy and patient tolerability of split-dose SPMC oral solution compared to PEG solution for colonoscopy bowel preparation. Methods: A systematic search was performed using Pubmed (MEDLINE), Web of Science, EMBASE, and Cochran Central Register of Controlled Trials databases. All studies on split-dose bowel preparation with SPMC and PEG were reviewed. Relevant studies regarding colonoscopy and bowel preparations were also included. Randomized controlled trials were prioritized due to the high quality of evidence. Results: Eight randomized controlled trials were included. Split-dose SPMC and PEG were associated with similar results for adequacy of bowel preparation. Split-dose SPMC was associated with increased patient tolerability and compliance. Conclusion: Split-dose SPMC and PEG are both adequate and safe for bowel preparation for outpatient colonoscopy, with split-dose SPMC being more tolerable for patients. Additional RCTs comparing these and other bowel preparation solutions are necessary to further investigate quality of bowel preparation, patient preference, and cost-effectiveness of the various options. [ABSTRACT FROM AUTHOR]

Growing demand for oil and gas has driven drilling activities to deep formations and complex well structures. Drilling fluid must be able to maintain wellbore integrity and thermal stability over extended drilling time. Besides, drilling fluid should produce high rate of penetration (ROP) and low damage to formation rock. Glycol mud satisfies these criteria thanks to its unique cloud point phenomenon. When temperature exceeds cloud point temperature, glycol starts precipitate from mud by forming micelles, coats the rock surface, and plugs the small fractures in rocks. As a result, the flow of mud into rocks is restricted and wellbore stability is improved. This paper surveys more than 40 wells that were drilled with glycol mud. Field cases reported good wellbore integrity, thermal stability, high ROP, and low formation damage. Glycol mud is an excellent choice for battling well instability and high temperatures. [ABSTRACT FROM AUTHOR]

The gas produced from the deposit usually contains various types of pollution. They are the reason for limiting its use, often making its use impossible. Therefore, it requires appropriate treatment. One of the main pollutants in gas is water. Its occurrence causes a lot of problems, especially at the stage of gas transport, such as the formation of hydrates blocking pipelines and apparatus, causes the phenomenon of condensation and corrosion of pipelines, especially if there is carbon dioxide or hydrogen sulphide in the gas. The paper presents a number of methods that enable drying of gas after extraction. Each of them has different parameters that will be achieved for the gas after it is dried. Depending on the required degree of drying, the economics of the process and compatibility with other dependent processes, the individual methods are more or less used in gas engineering. The paper discusses methods of absorption in ethylene glycol solutions, adsorption methods using silica gel, molecular sieves or calcium chloride and low-temperature processes such as Twister® supersonic separator, IFPEX-1® process and DexProTM process. [ABSTRACT FROM AUTHOR]

Featured Application: The ability of the THz-TDS to detect engine oil contamination with glycol at low concentrations. There continues to be a need for an in-situ sensor system to monitor the engine oil of internal combustion engines. Engine oil needs to be monitored for contaminants and depletion of additives. While various sensor systems have been designed and evaluated, there is still a need to develop and evaluate new sensing technologies. This study evaluated Terahertz time-domain spectroscopy (THz-TDS) for the identification and estimation of the glycol contamination of automotive engine oil. Glycol contamination is a result of a gasket or seal leak allowing coolant to enter an engine and mix with the engine oil. An engine oil intended for use in both diesel and gasoline engines was obtained. Fresh engine oil samples were contaminated with four levels of glycol (0 ppm, 150 ppm, 300 ppm, and 500 ppm). The samples were analyzed with THz-TDS and converted to frequency domain parameters of refractive index and absorption coefficient. While both parameters showed potential, the absorption coefficient had the best potential and was able to statistically discriminate among the four contamination levels. [ABSTRACT FROM AUTHOR]

Degumming bast fibers by organic solvents has been a promising method in recent years due to easy recovery and reuse of organic solvents. In this research, the possibility of ramie fiber degumming by glycol and a combination of acetic acid with glycol was studied, in which two steps were involved in the degumming process: distilled water boiling pretreatment and organosolv treatment by a combination of glycol/acetic acid (100/0, 90/10, 80/20, 70/30, 60/40, 50/50). Results displayed that the pretreatment could remove 6.99% of hemicellulose, 0.59% of lignin and 36.26% of other gums compared with raw ramie. While with organosolv treatment (130 °C, 6 h), fibers treated by glycol/acetic acid (50/50) had the best effect of removing gums. The hemicellulose and lignin content of fibers reduced by 44.81% and 54.12%, respectively (compared with raw ramie), while the residual gum content still failed to meet the requirements of spinning process. Besides, the tenacity of glycol/acetic acid treated fibers was lower than that of only glycol treated fibers (4.67 cN/dtex). Considering that the addition of acid could cause a decrease in fiber tenacity, the step of organosolv (only glycol) treatment was optimized by altering the degumming condition. The tenacity, linear density, non-cellulosic component ratio of fibers treated with the optimized condition (200 °C, 80 min) were 6.53 cN/dtex, 6.06 dtex, 5.78%, respectively, which met the needs of industrial production. Compared with the organosolv treated fibers, these properties of fibers with traditional alkaline treatment were better, but the yield (62.4%) was much lower than that of fibers treated with glycol in two degumming condition (77–82%). Considering impressive properties of the treated ramie, the method of organosolv degumming with high degumming efficiency and environmental protection would bring an innovative thought for natural fiber isolation. [ABSTRACT FROM AUTHOR]

The density of three glycols, namely Monoethylene glycol (MEG), Diethylene glycol (DEG), and Triethylene glycol (TEG) was measured in the temperature range from 298.15 K to 423.15 K and pressures up to 140.0 MPa using a vibrating tube density meter Anton Paar DMA-HPM, coupled with a high-pressure mPDS 5 unit. The modified Tait-Tammann equation was used to correlate the experimental density, which gave an absolute average relative deviation (AARD) of less than 0.2 %. Derived properties such as isobaric thermal expansion and isothermal compressibility coefficients were estimated and discussed. Furthermore, the density of the binary systems composed by the aforementioned glycols (1) + water (2) was also measured in the (273.15, 373.15) K temperature range at atmospheric pressure. The Cubic-Plus-Association (CPA) and the simplified version of the Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) equations of state were used to correlate the newly measured data, with deviations less than 3.7 % for pure component and 12.0 % for the binary systems. [ABSTRACT FROM AUTHOR]

• First report on aluminum reductant for the deoxydehydration (DODH) of glycols in the presence of pincer type Mo-catalyst. • Among the metal reductants examined, Al was found the best. • Easy separation from reductant from heterogeneous mixture. • Reaction is very easy to operate and carried out at 165–170 °C. • Moderate to high yield of DODH product formation. This study demonstrates that the zero-valent elements aluminum, zinc, iron, manganese, copper, and carbon are effective reductants for the ONO-pincer ligated molybdenum dioxo catalyzed deoxydehydration (DODH) of polyols. The reductants (elements) and their oxidized products remain insoluble during the reaction and can be easily separated. The cis -MoO 2 (dipic)L (dipic = pyridine-2,6-dicarboxylate); L=HMPA (Hexamethylphosphoramide), THF), and cis -MoO 2 (4-Chloro-dipic) HMPA catalysts (1) were found to be effective for the DODH of polyols. The stoichiometric experiments indicate a probable transition from Mo (VI) to Mo (IV) in the redox cycle for the DODH of polyols. [Display omitted] [ABSTRACT FROM AUTHOR]

The lack of a standard experimental procedure to determine thermal conductivity of fluids is noticeable in heat transfer processes from practical and fundamental perspectives. Since a wide variety of techniques have been used, reported literature data have huge discrepancies. A common practice is using manufactured thermal conductivity meters for nanofluids, which can standardize the measurements but are also somewhat inaccurate. In this study, a new methodology to perform reliable measurements with a recent commercial transient hot-wire device is introduced. Accordingly, some extensively studied fluids in the literature (water, ethylene glycol, ethylene glycol:water mixture 50:50 vol%, propylene glycol, and n-tetradecane) covering the range 0.100 to 0.700 W m−1 K−1 were used to check the device in the temperature range 283.15 to 333.15 K. Deviations between the collected data and the theoretical model, and repeatabilities and deviations between reported and literature values, were analyzed. Systematic deviations in raw data were found, and a correction factor depending on the mean thermal conductivity was proposed to operate with nanofluids. Considering all tested effects, the expanded (k = 2) uncertainty of the device was set as 5%. This proposed methodology was also checked with n-hexadecane and magnesium-oxide-based n-tetradecane nanofluids.

The combination of solid and liquid sorption media for thermal energy storage has been explored in order to improve heat flow as well as storage capacity with respect to the incomplete space-filling of closely packed solid sorbents. Three scenarios were elucidated from which in two cases the liquid/solid combinations perform worse than the neat liquid or solid and a third scenario where the combination performs better than the separate sorbents. We identified a mixture of zeolite 13XBF with tripropylene glycol as an example for such a superior combination showing a similar adsorption curve over time as the pure zeolite or glycol. After complete saturation of the zeolite in the mixture, glycol continues to absorb water, thereby increasing the overall capacity of the system. We identified a low direct attractive interaction (dipolar and dispersive) of the liquid sorbent (tripropylene glycol) with the solid sorbent (zeolite 13XBF) as a prerequisite for improved performance. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the continuation of our work on searching for anti-crystallization additives to the aqueous solution of lithium bromide is presented. This type of research is important from the viewpoint of absorption refrigeration technology to improve the performance of the efficiency of refrigeration equipment. In this study, three crown ethers: 12-crown-4, 15-crown-5, and 18-crown-6 as well as the glycols: ethylene glycol, diethylene glycol, triethylene glycol and glycerol were investigated as anti-crystallization additives for {LiBr (1) + water (2)} system, conventionally used as a working pair in absorption refrigeration technology. For this purpose, the solubility of lithium bromide in water has been determined in the presence of the organic additive. The solubility measurements have been carried out using a dynamic method at a wide temperature and composition range for different (additive to LiBr) initial mass fraction from w 2 0 = 0.1, 0.2 and 0.3. From experimental SLE data, the comparison range of the liquid state for tested systems at the absorber's working temperature was determined and compared to those from conventional (LiBr + water) system. Further measurements of vapor – liquid equilibria will be performed to select the best anti-crystallization additive. Highlights • Crown ethers and glycols have been investigated as an anti-crystallization additive for (LiBr + water) system. • The experimental data on solubility of {LiBr (1) + additive (2) + water (3)} at a wide temperature and composition range were presented. • Based on the SLE data anty-crystallization additive was chosen. [ABSTRACT FROM AUTHOR]

Abstract In this work the possibility of use glycols in extractive desulfurization will be discussed based on liquid–liquid phase equilibria (LLE) measurements for {glycol (1) + aromatic sulfur compound (2) + heptane (3)} ternary systems at T = 308.15 K and at pressure p = 0.1 MPa. Based on the experimental data, the performance of three glycols: diethylene glycol, triethylene glycol and polyethylene glycol (PEG 200) in the extraction of thiophene, or benzothiophene from heptane were determined. The selectivity, S , and solute distribution ratio, β derived from the experimental equilibrium data, were calculated and used to determine the efficiency of the tested glycols as a solvent for the extraction of sulfur compounds from model fuels. The NRTL equation was successfully used to correlate the experimental tie-lines and calculate the phase composition error in mole fraction in the ternary systems. The average root mean square deviation (RMSD) of the phase composition was less than 0.017. Additionally, the extractive desulfurization (EDS) of model fuels has been studied using diethylene glycol, triethylene glycol, polyethylene glycols (PEG 200), [BMIM][BF 4 ] and eutectic mixtures of ([BMMOR][Br with diethylene glycol, or triethylene glycol). The oxidative extractions (ODS) were performed using different oxidative agents: the mixture of hydrogen peroxide with acetic acid, or formic acid, or benzoic acid, or iron (III) chloride and vanadium (V) oxide as well as the mixture of oxygen with N -hydroxyphthalimide (NHPI). Many parameters including the type of extractant and oxidizing agents, extraction time and temperature, as well as the ratio of the volume of model fuel to the volume of the extractant and number of extraction cycles on the extraction efficiency, were considered and discussed. Highlights • LLE data for {glycol + thiophene/benzothiophene + heptane) were determined. • The S and β for the extraction of thiophene/benzothiophene from heptane were presented. • The NRTL model satisfactorily correlates the LLE data. • Oxidative desulfurization is investigated. • The influence of many parameters on extraction efficiency were presented. [ABSTRACT FROM AUTHOR]

There continues to be a need for an in-situ sensor system to monitor the engine oil of internal combustion engines. Engine oil needs to be monitored for contaminants and depletion of additives. While various sensor systems have been designed and evaluated, there is still a need to develop and evaluate new sensing technologies. This study evaluated Terahertz time-domain spectroscopy (THz-TDS) for the identification and estimation of the glycol contamination of automotive engine oil. Glycol contamination is a result of a gasket or seal leak allowing coolant to enter an engine and mix with the engine oil. An engine oil intended for use in both diesel and gasoline engines was obtained. Fresh engine oil samples were contaminated with four levels of glycol (0 ppm, 150 ppm, 300 ppm, and 500 ppm). The samples were analyzed with THz-TDS and converted to frequency domain parameters of refractive index and absorption coefficient. While both parameters showed potential, the absorption coefficient had the best potential and was able to statistically discriminate among the four contamination levels.