Mechanism of pore relative humidity on salt swelling characteristics in sulfate saline soil

The paper presents some results of experimental program focused on drying and shrinkage of large concrete specimens. Segments of walls with thicknesses 200, 400 and 800 mm and standard cylinders 150x300 mm were used as specimens. Each segment has embedded 4 vibrating wire strain gauges in axis plane for measurements of shrinkage strain and plastic tubes of various lengths for measurements of pore relative humidity in different depths. Relative humidity and temperature of ambient environment were not controlled, however they were recorded very closely. Measure shrinkage strains are compared with prediction based on shrinkage models. The most important predictive models are used for comparison: Model Code 2010, Eurokód 2, Model ACI 209-R92, Model B4 a Model B4s.

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Experimental Study on Influence of Vaporous Water on Salt Expansion of Sulfate Saline Soil

Advances in Civil Engineering ◽

10.1155/2019/6819460 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

Shuquan Peng ◽

Fan Wang ◽

Ling Fan

Keyword(s):

Relative Humidity ◽

Liquid Water ◽

Sodium Sulfate ◽

Saline Soil ◽

Sulfate Solution ◽

Experimental Results ◽

X Ray Diffraction ◽

Expansion Test ◽

Expansion Mechanism ◽

New Treatment

The harm of salt expansion of saline soil in arid areas has always been a major problem to be solved urgently. According to the conversion rule between sodium sulfate and sodium sulfate decahydrate, sodium sulfate decahydrate crystals can be precipitated from sodium sulfate solution by cooling. Besides, when the relative humidity (RH) exceeds the critical relative humidity (CRH), sodium sulfate decahydrate can be formed by the combination of sodium sulfate and vaporous water, resulting in the salt volume expansion. However, at present, in the salt expansion mechanism of sulfate saline soil, only the influence of liquid water is considered while vaporous water is not involved. To study the effects of temperature, salinity, and ARH on salt expansion, the salt expansion test of dry sulfate saline soil under the action of vaporous water was conducted, and its composition was analyzed by X-ray diffraction (XRD) technology. Experimental results showed that sodium sulfate decahydrate crystals were produced in the sulfate saline soil if the relative humidity (RH) of pore gas exceeded the critical one so that salt expansion occurred. Salt expansion and salt expansion rate of sulfate saline soil increased with the increase of RH and salinity but decreased with the increase of temperature. Therefore, the new salt expansion mechanism of sulfate saline soil under vaporous water is verified. The experimental results further perfected the original salt expansion mechanism of sulfate saline soil under the action of liquid water and guided the study of new treatment methods of sulfate saline soil.

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Effect of relative humidity on the rate of dissolution of aluminium in iodine-methanol solution

Journal of Biochemical Toxicology ◽

10.1002/jbt.2570091004 ◽

1959 ◽

Vol 9 (10) ◽

pp. 519-520

Author(s):

D. F. Maclennan

Keyword(s):

Relative Humidity ◽

Methanol Solution ◽

Rate Of Dissolution

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168. Prediction of the Effect of High Relative Humidity on Organic Vapor Cartridge Performance

10.3320/1.2765684 ◽

2001 ◽

Author(s):

E. Johnson ◽

L. Brey

Keyword(s):

Relative Humidity ◽

High Relative Humidity ◽

Organic Vapor

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

FLORA AND FAUNA ◽

10.33451/florafauna.v24i1pp155-162 ◽

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.

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

FLORA AND FAUNA ◽

10.33451/florafauna.v25i1pp91-99 ◽

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.

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