The effect of relative humidity on the gas permeability and swelling in PFSI membranes

2012 ◽  
Vol 37 (7) ◽  
pp. 6308-6316 ◽  
Author(s):  
J. Catalano ◽  
T. Myezwa ◽  
M.G. De Angelis ◽  
M. Giacinti Baschetti ◽  
G.C. Sarti
Keyword(s):  
Relative Humidity ◽  
Gas Permeability

scholarly journals Design and application of a microfluidic device for protein crystallization using an evaporation-based crystallization technique

2011 ◽  
Vol 45 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Yong Yu ◽  
Xuan Wang ◽  
Dominik Oberthür ◽  
Arne Meyer ◽  
Markus Perbandt ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Microfluidic Device ◽  
Gas Permeability ◽  
Protein Crystallization ◽  
Microfluidic Devices ◽  
Protein Crystals ◽  
Air Bubbles ◽  
Crystallization System ◽  
Relationship Of

A new crystallization system is described, which makes it possible to use an evaporation-based microfluidic crystallization technique for protein crystallization. The gas and water permeability of the used polydimethylsiloxane (PDMS) material enables evaporation of the protein solution in the microfluidic device. The rates of evaporation are controlled by the relative humidity conditions, which are adjusted in a precise and stable way by using saturated solutions of different reagents. The protein crystals could nucleate and grow under different relative humidity conditions. Using this method, crystal growth could be improved so that approximately 1 mm-sized lysozyme crystals were obtained more successfully than using standard methods. The largest lysozyme crystal obtained reached 1.57 mm in size. The disadvantage of the good gas permeability in PDMS microfluidic devices becomes an advantage for protein crystallization. The radius distributions of aggregrates in the solutions inside the described microfluidic devices were derived fromin situdynamic light scattering measurements. The experiments showed that the environment inside of the microfluidic device is more stable than that of conventional crystallization techniques. However, the morphological results showed that the protein crystals grown in the microfluidic device could lose their morphological stability. Air bubbles in microfluidic devices play an important role in the evaporation progress. A model was constructed to analyze the relationship of the rates of evaporation and the growth of air bubbles to the relative humidity.

Positronium Lifetimes and Gas Permeation in Aquivion® for Fuel Cells

2012 ◽  
Vol 733 ◽  
pp. 61-64 ◽  
Author(s):  
Hamdy F.M. Mohamed ◽  
Yoshinori Kobayashi ◽  
Seiichi Kuroda ◽  
Akihiro Ohira
Keyword(s):  
Fuel Cells ◽  
Relative Humidity ◽  
Free Volume ◽  
Room Temperature ◽  
Gas Permeability ◽  
Gas Permeation ◽  
Positronium Lifetime ◽  
Different Temperatures ◽  
Linear Correlations

Variations of ortho-positronium (o-Ps) lifetime and gas permeability of the Aquivion® E8705 membrane were studied as functions of temperature under vacuum and relative humidity at room temperature. When the temperature was varied between 0 and 100 °C in vacuum, the hole volume of Aquivion® E8705, deduced from the ortho-positronium lifetime, gradually increased. However, when the relative humidity was changed at room temperature, the hole volume was essentially unchanged. Good linear correlations between the logarithm of permeabilities of O2 and H2 and reciprocal hole volume at different temperatures indicates the importance role of free volume in gas permeation in dry Aquivion® E8705. However, for hydrated Aquivion® E8705 the permeability less depends on hole volume.

THE EFFECT OF OILING AND AIR CELL MOLD ON THE OXYGEN AND CARBON DIOXIDE CONTENTS OF THE AIR CELLS OF EGGS

1950 ◽  
Vol 28f (5) ◽  
pp. 101-106
Author(s):  
Dyson Rose ◽  
N. E. Gibbons
Keyword(s):  
Carbon Dioxide ◽  
Relative Humidity ◽  
Gas Permeability ◽  
Mold Growth ◽  
Gas Composition ◽  
Carbon Dioxide Content ◽  
High Carbon ◽  
Moisture Vapor ◽  
Air Cells ◽  
High Carbon Dioxide

The gas contained in the air cells of day old eggs had a high carbon dioxide content, but during storage the gas composition approached that of the surrounding atmosphere. Oiling of the egg, or otherwise sealing the shell, tended to retain carbon dioxide in the air cell. Growth of mold in the air cell, or of bacteria in the egg contents, markedly reduced the oxygen content and increased the carbon dioxide content of the air cell gas. Permeability of the shell of unoiled eggs to moisture vapor was low and the relative humidity in the air cell was shown to be 99% or higher. Oiling of the eggs cannot therefore promote mold growth by increasing the humidity in the air cell.

scholarly journals Gas Permeability of Fruit Coating Waxes

1992 ◽  
Vol 117 (1) ◽  
pp. 105-109 ◽  
Author(s):  
Robert D. Hagenmaier ◽  
Philip E. Shaw
Keyword(s):  
Water Vapor ◽  
Relative Humidity ◽  
Respiration Rate ◽  
Gas Permeability ◽  
High Permeability ◽  
Carnauba Wax ◽  
Noncondensable Gas ◽  
Noncondensable Gases ◽  
Fruit Coating

The permeability to O2, CO2, C2H4, and water vapor was determined for 19 commercial fruit wax coatings, four ingredients thereof, and one shrink-wrap film. For the commercial coatings, the O2permeability at 50% relative humidity and 30C ranged from 470 to 22,000 ml (STP) × mil/(m2 × day × atm) (1 mil = 0.0254 mm) with CO)2. permeability two to eight times as high. Permeability to noncondensable gases tended to be higher for coatings made from carnauba wax than for those made from shellac and rosin. Commercial fruit wax had sufficiently low noncondensable gas permeability to account for large reductions in the respiration rate of coated fruit. Wax coatings could be improved if permeability were controlled:

EPIDEMIOLOGY, ECOLOGY AND PREVALENCE OF SOIL TRANSMITTED HELMINTHS FROM KOSHI REGION OF NORTH BIHAR.

2018 ◽  
Vol 24 (1) ◽  
Author(s):  
LAKSHMI CHOUDHARY ◽  
PRABHAWATI PRABHAWATI
Keyword(s):  
Relative Humidity ◽  
Ascaris Lumbricoides ◽  
Rainy Season ◽  
Climatic Factors ◽  
Trichuris Trichiura ◽  
Hookworm Infection ◽  
Soil Transmitted Helminths ◽  
High Incidence ◽  
Apparently Healthy

Prevalence of soil transmitted helminthes infections in apparently healthy school going children and other 528 people of different districts of Koshi regions of North Bihar were evaluated. Over all incidences of STHs infection was 39.39% during study. High incidence of STH was seen in the rainy season i.e., in the month of July and August, September, significantly higher (P<0.05) .The incidence of Ascaris lumbricoides was highest in the month of August (18.64%). The month of September was 15.25% followed by that of July (14.4%) and October with 10.16%. Also the incidence of hookworm registered the highest incidence in the month of June (19.27%) and lowest in the month of December (4.82%) during the study period. However prevalence of Trichuris trichiura was negligible and it was almost nil in the most of the months but was highest in month of September with 28.57% and lowest in October with 14.00% The climatic factors are responsible for soil transmitted helminthes which are temperature, rainfall and relative humidity. Ascariasis, Trichuriasis and Ancyclostomiasis (Hookworm infection) are found to be endemic in this region.

EL NINO RELATED CLIMATE AND DENGUE FEVER CASES IN JEDDAH, SAUDI ARABIA

2019 ◽  
Vol 25 (1) ◽  
Author(s):  
MASROOR ALI KHAN ◽  
KHALID AL GHAMDI ◽  
JAZEM A. MEHYOUB ◽  
RAKHSHAN KHAN
Keyword(s):  
Relative Humidity ◽  
Dengue Fever ◽  
El Niño ◽  
Significant Relationship ◽  
El Nino ◽  
Climate Data ◽  
Light Traps ◽  
Mosquito Abundance ◽  
Dengue Transmission ◽  
The Relationship

The focus of this study is to find the relationship between El Nino and dengue fever cases in the study area.Mosquito density was recorded with the help of light traps and through aspirators collection. Climate data were obtained from National Meteorology and Environment centre. (Year wise El Nino and La Nina data are according to NOAA & Golden Gate Weather Services). Statistical methods were used to establish the correlation coefficient between different factors. A high significant relationship was observed between Relative Humidity and Dengue fever cases, but Aedes abundance had no significant relationship with either Relative humidity and Temperature. Our conclusion is that the El Nino does not affect the dengue transmission and Aedes mosquito abundance in this region, which is supported by earlier works.

Effect of interlayer cation and relative humidity on the hydration properties of a dioctahedral smectite

2007 ◽  
Vol 2007 (suppl_26) ◽  
pp. 417-422 ◽  
Author(s):  
W. Oueslati ◽  
M. S. Karmous ◽  
H. Ben Rhaiem ◽  
B. Lanson ◽  
A. Ben Haj Amara
Keyword(s):  
Relative Humidity ◽  
Interlayer Cation ◽  
Hydration Properties ◽  
Dioctahedral Smectite
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