Cyclopentasiloxane (D5) as a Non-Polar Masking Agent for Water-Sensitive Substrates During Polar Solvent Treatment

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Karen Köhler ◽  
Irene Brückle ◽  
Ute Henniges
Keyword(s):  
Barrier Function ◽  
Artificial Aging ◽  
Polar Solvent ◽  
Water Immersion ◽  
Water Soluble ◽  
Water Absorbency ◽  
Water Mixture ◽  
Solvent Treatment ◽  
Ethanol Mixture ◽  
Aqueous Treatment

Abstract D5 (decamethylcyclopentasiloxane), a non-polar solvent that evaporates slowly, was tested for its suitability as a temporary masking agent for water-sensitive media on paper objects undergoing aqueous treatment. Three different treatment-related settings were tested on five different paper types, some prepared with water-soluble inks. In 10-min water immersion treatments, D5 proved largely ineffectual in protecting the water-soluble inks. In conjunction with melt-applications of cyclododecane, the addition of D5 enhanced its barrier function only in one case. To test the ability of D5 to prevent tideline formation, the test samples received applications of water, acetone, and a water-ethanol-mixture, creating an interface with freshly D5-impregnated areas. The papers were evaluated visually (VIS, UVA), some after artificial aging. D5 diminished the formation of visible tidelines in the two internally sized papers with low water absorbency in contact with acetone and the ethanol-water mixture, but did not prevent tidelines in contact with water. It also did not protect water-absorbent paper. The results indicate that D5, which is miscible with ethanol and acetone, may disperse tidelines caused by these solvents, but it proved largely insufficient for protecting media during water immersion.

Absence of Na+–H+ barrier function in mucosa of canine small bowel

1978 ◽  
Vol 56 (4) ◽  
pp. 617-623 ◽  
Author(s):  
Darlene G. Kelly ◽  
Charles F. Code
Keyword(s):  
Small Intestine ◽  
Small Bowel ◽  
Barrier Function ◽  
Hexanoic Acid ◽  
Water Soluble ◽  
Mucosal Barrier ◽  
Jejunal Mucosa ◽  
Gastric Corpus ◽  
Gastric Mucosal Barrier ◽  
Made In

The study was designed to determine whether the special Na+–H+ barrier function or the gastric mucosa is present in the mucosa of the small bowel and whether a gastric mucosal barrier breaker (hexanoic acid) would accelerate the fluxes of sodium in duodenum–jejunum and ileum as in the stomach. The observations were made in healthy conscious dogs with Thiry-Vella fistulae of the small bowel or Heidenhain pouches of the gastric corpus. These barrier characteristics of the stomach were completely absent in the small intestine where bidirectional Na fluxes were 5–10 times greater than in the stomach and were not accelerated by hexanoic acid as they were in the stomach.A comparison was made between the rates of absorption of hexanoic acid, sodium hexanoate, and HCl from the pouches and fistulae. The lipid-soluble fatty acid was transported at all sites more rapidly than its water-soluble sodium salt. In the stomach and ileum the H+ of HCl and sodium hexanoate were absorbed at similar slow rates. The duodenal–jejunal mucosa, however, transported H+ at rates nearly identical to those of hexanoic acid. In our tests HCl was not neutralized in duodenal contents while large quantities were neutralized in the contents of ileum.

scholarly journals Towards closing the gap between hygroscopic growth and activation for secondary organic aerosol – Part 2: Theoretical approaches

2009 ◽  
Vol 9 (12) ◽  
pp. 3999-4009 ◽  
Author(s):  
M. D. Petters ◽  
H. Wex ◽  
C. M. Carrico ◽  
E. Hallbauer ◽  
A. Massling ◽  
...  
Keyword(s):  
Water Activity ◽  
Secondary Organic Aerosol ◽  
Cloud Condensation Nuclei ◽  
Organic Aerosol ◽  
Water Soluble ◽  
Water Mixture ◽  
Hygroscopic Growth ◽  
Ideal Behavior ◽  
Hygroscopic Properties ◽  
Theoretical Approaches

Abstract. We examine the hygroscopic properties of secondary organic aerosol particles generated through the reaction of α-pinene and ozone using a continuous flow reaction chamber. The water activity versus composition relationship is calculated from measurements of growth factors at relative humidities up to 99.6% and from measurements of cloud condensation nuclei activity. The observed relationships are complex, suggesting highly non-ideal behavior for aerosol water contents at relative humidities less than 98%. We present two models that may explain the observed water activity-composition relationship equally well. The first model assumes that the aerosol is a pseudo binary mixture of infinitely water soluble compounds and sparingly soluble compounds that gradually enter the solution as dilution increases. The second model is used to compute the Gibbs free energy of the aerosol-water mixture and shows that the aerosol behaves similarly to what can be expected for single compounds that contain a certain fraction of oxygenated and non-polar functional groups.

scholarly journals Optoelectronics: High-Performance Planar Perovskite Optoelectronic Devices: A Morphological and Interfacial Control by Polar Solvent Treatment (Adv. Mater. 23/2015)

2015 ◽  
Vol 27 (23) ◽  
pp. 3465-3465 ◽  
Author(s):  
Jae Choul Yu ◽  
Da Bin Kim ◽  
Gyoelim Baek ◽  
Bo Ram Lee ◽  
Eui Dae Jung ◽  
...  
Keyword(s):  
High Performance ◽  
Polar Solvent ◽  
Optoelectronic Devices ◽  
Solvent Treatment

scholarly journals Towards closing the gap between hygroscopic growth and activation for secondary organic aerosol – Part 2: Theoretical approaches

2008 ◽  
Vol 8 (6) ◽  
pp. 20839-20867 ◽  
Author(s):  
M. D. Petters ◽  
H. Wex ◽  
C. M. Carrico ◽  
E. Hallbauer ◽  
A. Massling ◽  
...  
Keyword(s):  
Water Activity ◽  
Secondary Organic Aerosol ◽  
Cloud Condensation Nuclei ◽  
Organic Aerosol ◽  
Water Soluble ◽  
Water Mixture ◽  
Hygroscopic Growth ◽  
Ideal Behavior ◽  
Hygroscopic Properties ◽  
Theoretical Approaches

Abstract. We examine the hygroscopic properties of secondary organic aerosol particles generated through the reaction of alpha-pinene and ozone using a continuous flow reaction chamber. The water activity versus composition relationship is calculated from measurements of growth factors at relative humidities up to 99.6% and from measurements of cloud condensation nuclei activity. The observed relationships are complex, suggesting highly non-ideal behavior for aerosol water contents at relative humidities less than 98%. We present two models that may explain the observed water activity-composition relationship equally well. The first model assumes that the aerosol is a pseudo binary mixture of infinitely water soluble compounds and sparingly soluble compounds that gradually enter the solution as dilution increases. The second model is used to compute the Gibbs free energy of the aerosol-water mixture and shows that the aerosol behaves similarly to what can be expected for single compounds that contain a certain fraction of oxygenated and non-polar functional groups.

Sorption of Inorganic Substances on the Porous Latvian Clay Ceramic

2012 ◽  
Vol 51 (4) ◽  
pp. 383-388 ◽  
Author(s):  
L. Dabare ◽  
R. Svinka ◽  
V. Svinka
Keyword(s):  
Water Immersion ◽  
Mercury Porosimetry ◽  
Water Soluble ◽  
Ph Values ◽  
Inorganic Substances ◽  
Sorption Ability ◽  
Different Temperatures ◽  
Molecular Substances ◽  
Entire Amount ◽  
Clay Pellets

Devonian clay of Liepa deposit (district of Cesis) and Quaternary clay of Laza deposit (district of Aizpute) was investigated. Pellets were fired at four different temperatures of 700, 800, 900, and 1050 °C. Porosity and surface area of pellets was determined by mercury porosimetry. The pH values after water immersion of fired pellets was determined with a pHmeter. The sorption ability of molecular substance (iodine) and ionic substances (ammonia and dichromate) were determined by titrimetric methods. The best sorption ability was found for iodine molecules. The entire amount of iodine in the water suspension was absorbed in two weeks, and the sorption ability reached 12.5 mg/g for samples fired at 700 and 800 °C temperature for the Liepa clay and 13.0 mg/g for the Laza clay. The sorption ability of these clay pellets for ammonia was lower and amounted to 3.0 and 2.5 mg/g, respectively. The sorption ability for dichromate ion was even less - only 0.6 mg/g for pellets of both clays. The investigated fired porous clay granules exhibited distinct sorption properties towards water-soluble ionic and molecular substances, which depended more on the firing temperature of granules and less on the source of clay.

Development of Water Adsorbents Synthesized from Spent Bleaching Earth to Dehydrate Ethanol Water Mixture

2014 ◽  
Vol 970 ◽  
pp. 187-191
Author(s):  
Zharin Shah Abd Aziz ◽  
Abdurahman Hamid Nour ◽  
Mohd Yunos Rosli
Keyword(s):  
Aging Temperature ◽  
Bleaching Earth ◽  
Distilled Water ◽  
Water Mixture ◽  
Fusion Method ◽  
Zeolite A ◽  
Karl Fischer Titration ◽  
Ethanol Mixture ◽  
Karl Fischer ◽  
Closed Container

Water adsorbent to dehydrate water ethanol mixture was synthesized from spent bleaching earth (SBE) using modified fusion method. The SBE was regenerated using heat at 750°C. Predetermined alumina, Al2O3and a stochiometric amount of KOH was added to the regenerated SBE, mixed and fused at several temperatures for 12 hours in a furnace. The fused mixture was grounded and mixed with water to get 40-55% KOH solution in water. This mixture was aged for several pre determined temperature for several pre determined days in a closed container before crystallization took place in 5 part by weight 5% KOH for 48 hours. The product obtained was washed 3 times with distilled water using filtration set and dried in oven at 220°C for 20 hours. Results from Karl Fischer Titration showed that the product was able to absorb water up above 0.0200 g/g adsorbent which was approximately 50% performance of commercial zeolite A. The best conditions for synthesizing the water adsorbent from SBE were : 80 g alumina added per 100 gram kaolin, fused temperature of 650°C, aging temperature of 80°C for 5 days. However, XRD results showed that the synthesized product was not the type of zeolite A.

scholarly journals REPLACING SODA ASH (NaOH) WITH KALIUM HYDROXYDE (KOH) IN DESTILATION OF BINARY ETHANOL-WATER MIXTURE

2016 ◽  
Vol 12 (2) ◽  
pp. 179
Author(s):  
Ana Ulfa Istiqomah ◽  
Fitria Rahmawati ◽  
Khoirina Dwi Nugrahaningtyas
Keyword(s):  
Enthalpy Of Mixing ◽  
Sodium Content ◽  
Vaporization Enthalpy ◽  
Second Step ◽  
Water Mixture ◽  
Ethanol Mixture ◽  
High Sodium ◽  
Azeotropic Point ◽  
Colligative Properties ◽  
Soda Ash

<p class="Default">Soda ash (NaOH) has been used in bioethanol production in the second step destillation to increase the purity up to 90%. The destillation process will produce waste water with a high sodium content. The soda ash itself serve as an electrolyte to modify the colligative properties of the water-ethanol mixture allowing the disappearance of azeotropic point. This research aims to study the replacement of NaOH with KOH, in which the kalium is a nutrient to maintain soil fertility. This research study the thermodynamics properties, vapor-liquid equilibrium, colligative properties and also its azeotropic point in the destillation of water-ethanol mixture when KOH and NaOH were used as the additive. A model of water-ethanol mixture at a various composition of 0-100 weight % of ethanol was used. The electrolyte addition was 0.1 mol electrolyte/total weight of ethanol-water. The result shows that the addition of electrolyte into ethanol-water mixture eliminate the azeotropic point and allows the ethanol molecules to separate from water. The enthalpy of mixing between water-ethanol is 239.601 kJ/mol. It becomes 259.796 kJ/mol and 264.793 kJ/mol after the addition of NaOH and KOH, respectively. It confirming the endothermic mixing process due to different polarity between water and ethanol. The presence of electrolyte even reduce more their molecular interaction. However, the change to irregularity result a high positive entropy values that result the negative Gibbs free energy. It confirms the spontaneity of mixing. The vaporization enthalpy, H<sub>vap</sub>, of water-ethanol mixture is 76.229 kJ/mol and it becomes 235.366 kJ/mol and 126.189 kJ/mol after the addition of NaOH and KOH. It indicates that the presence of electrolyte inhibites vaporization of water as the major component and allowing ethanol molecules to vapor producing more high purity ethanol.</p>

scholarly journals Impact of Water Exposure and Temperature Changes on Skin Barrier Function

2022 ◽  
Vol 11 (2) ◽  
pp. 298
Author(s):  
Manuel Herrero-Fernandez ◽  
Trinidad Montero-Vilchez ◽  
Pablo Diaz-Calvillo ◽  
Maria Romera-Vilchez ◽  
Agustin Buendia-Eisman ◽  
...  
Keyword(s):  
Barrier Function ◽  
Skin Diseases ◽  
Cold Water ◽  
Water Immersion ◽  
Skin Barrier ◽  
Hot Water ◽  
Skin Barrier Function ◽  
Inflammatory Skin Diseases ◽  
Water Exposure ◽  
The Impact

The frequency of hand hygiene has increased due to the COVID-19 pandemic, but there is little evidence regarding the impact of water exposure and temperature on skin. The aim of this study is to evaluate the effect of water exposure and temperature on skin barrier function in healthy individuals. A prospective observational study was conducted. Temperature, pH, transepidermal water loss (TEWL), erythema and stratum corneum hydration (SCH) were measured objectively before and after hot- and cold-water exposure and TempTest® (Microcaya TempTest, Bilbao, Spain) contact. Fifty healthy volunteers were enrolled. Hot-water exposure increased TEWL (25.75 vs. 58.58 g·h−1·m−2), pH (6.33 vs. 6.65) and erythema (249.45 vs. 286.34 AU). Cold-water immersion increased TEWL (25.75 vs. 34.96 g·h−1·m−2) and pH (6.33 vs. 6.62). TEWL (7.99 vs. 9.98 g·h−1·m−2) and erythema (209.07 vs. 227.79 AU) increased after being in contact with the hot region (44 °C) of the TempTest. No significant differences were found after contact with the cold region (4 °C) of the TempTest. In conclusion, long and continuous water exposure damages skin barrier function, with hot water being even more harmful. It would be advisable to use cold or lukewarm water for handwashing and avoid hot water. Knowing the proper temperature for hand washing might be an important measure to prevent flares in patients with previous inflammatory skin diseases on their hands.

Loss of Elements From Anhydrously Fixed Pollen During Thin Sectioning

1990 ◽  
Vol 48 (2) ◽  
pp. 330-331
Author(s):  
Hilary R. Skilnyk ◽  
John N.A. Lott
Keyword(s):  
Propylene Oxide ◽  
Pollen Grains ◽  
Water Soluble ◽  
Energy Dispersive ◽  
Cucurbita Maxima ◽  
Cell Cytoplasm ◽  
Ethanol Mixture ◽  
X Ray ◽  
Thin Sectioning ◽  
Tube Cell

Anhydrous fixations are not commonly considered as a means of preparing biological specimens for energy-dispersive x-ray analysis (EDX). Cucurbita maxima and Cucurbita andreana pollen grains were fixed anhydrously because water-soluble materials such as potassium phytate are extracted by aqueous fixatives. Combining anhydrous fixation with anhydrous sectioning techniques demonstrated significant reduction in the extraction of K, Mg and P from globoid particles in the tube cell cytoplasm in pollen.Air-dried Cucurbita maxima and Cucurbita andreana pollen grains were fixed for 4h in 2% paraformaldehyde dissolved in pure glycerol (W/V). Samples were washed for 1.5 h in (1:1) glycerol: 100% ethanol mixture. Dehydration began at 95% ethanol because glycerol is hygroscopic and not completely anhydrous. Infiltration was carried out beginning with propylene oxide followed by a series of Spurr’s resin: propylene oxide mixtures which consisted of 1:3, 1:2, 1:1, 2:1, and 3:1 proportions that were followed by three changes of 100% resin.

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