scholarly journals The effect of saturation Methods on natural gypsum rocks

2021 ◽  
Vol 877 (1) ◽  
pp. 012006
Author(s):  
Dhafar abdulrahman ◽  
Falah Hasan ◽  
Amjad Ibrahim
Keyword(s):  
Weight Gain ◽  
Relative Humidity ◽  
Calcium Sulfate ◽  
Potable Water ◽  
High Humidity ◽  
Sulfate Salt ◽  
Humid Environment ◽  
Gypsum Rock ◽  
Water Saturated ◽  
Closed Environment

Abstract When the gypsum rock is exposed to the relative humidity in a closed environment for a continuous period, the result is an increase in the weight of these rocks after the passage of the first 24 hours, and there is no effect on the percentage of gypsum that the rocks contain, as the weight increase occurred at the same time for the different gypsum ratios. For rocks submerged in potable water and located within a humid environment, most of these rocks witnessed weight gain, with some exhibiting dissolving behavior. As for the gypsum rocks submerged with water saturated with aqueous calcium sulfate salt, they witnessed weight gain without any solubility. It is worth noting the important effect that relative humidity plays in the atmosphere at high levels, as it stimulated the saturation property to cover and overcome the famous property of gypsum rocks, which is the melting at high humidity.

STUDIES OF THE AGING OF CONIDIA OF MONILINIA FRUCTICOLA (WINT.) HONEY: I.GERMINATION RATES AND LONGEVITY

1957 ◽  
Vol 35 (5) ◽  
pp. 635-645 ◽  
Author(s):  
S. H. Z. Naqvi ◽  
H. M. Good
Keyword(s):  
Relative Humidity ◽  
Storage Temperature ◽  
Potato Dextrose Agar ◽  
Monilinia Fructicola ◽  
High Humidity ◽  
Percentage Germination ◽  
Low Humidity ◽  
Nutrient Solutions

Conidia of Monilinia fructicola (Wint.) Honey were stored 1–10 months at temperatures of 5°, 25°, and 35 °C. and at constant relative humidities approximating 0, 15, 45, 75, and 90%. The germination of these spores was tested on potato dextrose agar containing 6% glucose, and curves of the percentage germination against time are given for representative samples.A pronounced delay in germination developed under all conditions of storage. The rate at which this delay developed was virtually independent of the storage temperature. All spore samples gave 100% germination after 3 months but only those at 5 °C. gave; any germination after 10 months. Storage in a relative humidity of 75% gave the best preservation of spore vigor, there being evidence in other conditions of either high humidity or low humidity injury. Of the nutrient solutions tested, glucose was the only one which gave substantially better germination than water, the effect being most marked on spores stored for some months at high humidity. With glucose, such spores sometimes germinated faster than those stored at intermediate humidities.

Episodic basin-scale soil moisture anomalies associated with high relative humidity events in the McMurdo Dry Valleys, Antarctica

2021 ◽  
pp. 1-15
Author(s):  
Joseph Levy
Keyword(s):  
Soil Moisture ◽  
Relative Humidity ◽  
Mcmurdo Dry Valleys ◽  
Limiting Factor ◽  
High Humidity ◽  
Dry Valleys ◽  
Surface Soils ◽  
Basin Scale ◽  
Soil Reflectance

Abstract Outside of hydrologically wetted active layer soils and humidity-sensitive soil brines, low soil moisture is a limiting factor controlling biogeochemical processes in the McMurdo Dry Valleys. But anecdotal field observations suggest that episodic wetting and darkening of surface soils in the absence of snowmelt occurs during high humidity conditions. Here, I analyse long-term meteorological station data to determine whether soil-darkening episodes are present in the instrumental record and whether they are, in fact, correlated with relative humidity. A strong linear correlation is found between relative humidity and soil reflectance at the Lake Bonney long-term autonomous weather station. Soil reflectance is found to decrease annually by a median of 27.7% in response to high humidity conditions. This magnitude of darkening is consistent with soil moisture rising from typical background values of < 0.5 wt.% to 2–3 wt.%, suggesting that regional atmospheric processes may result in widespread soil moisture generation in otherwise dry surface soils. Temperature and relative humidity conditions under which darkening is observed occur for hundreds of hours per year, but are dominated by episodes occurring between midnight and 07h00 local time, suggesting that wetting events may be common, but are not widely observed during typical diel science operations.

Tar and Nicotine in Cigarette Smoke

1969 ◽  
Vol 52 (3) ◽  
pp. 458-462 ◽  
Author(s):  
H C Pillsbury ◽  
C C Bright ◽  
K J O"Connor ◽  
F W Irish
Keyword(s):  
Gas Chromatography ◽  
Weight Gain ◽  
Relative Humidity ◽  
Cigarette Smoke ◽  
Confidence Level ◽  
Coefficient Of Variation ◽  
Random Order ◽  
Filter Holder ◽  
Isopropanol Solution

Abstract Cigarettes were conditioned 24 hr at 75°F and 60% relative humidity prior to being selected and smoked in a random order. Cigarettes were smoked in a Cambridge filter holder on an automatic smoking machine to a pre-determined butt length. TPM wet collection was on a CM113A filter disk and was determined as the net weight gain in the Cambridge filter holder after smoking. The filter pads were extracted with dioxane-isopropanol solution and were analyzed for moisture by gas chromatography. The pads and solvent extracts were steam distilled and the distillate was analyzed spectrophotometrically for nicotine. TPM dry was calculated as TPM wet minus nicotine and water. The coefficient of variation in this method is less than 5% with a 95% confidence level.

scholarly journals Development of MILIONCAST, an Improved Model for Predicting Downy Mildew Sporulation on Onions

Plant Disease ◽  
2004 ◽  
Vol 88 (7) ◽  
pp. 695-702 ◽  
Author(s):  
Tijs Gilles ◽  
Kath Phelps ◽  
John P. Clarkson ◽  
Roy Kennedy
Keyword(s):  
Relative Humidity ◽  
Environmental Conditions ◽  
Temporal Pattern ◽  
Random Model ◽  
Controlled Environment ◽  
High Humidity ◽  
Potted Plants ◽  
Effects Of Temperature ◽  
Improved Model ◽  
Accuracy Of Prediction

The effects of temperature and relative humidity on Peronospora destructor sporulation on onion (Allium cepa) leaves were studied under controlled environmental conditions. Sporangia were produced most rapidly at 8 to 12°C after 5 h of high humidity during dark periods. The greatest number of sporangia was produced at 100% relative humidity (RH), and sporulation decreased to almost nil when humidity decreased to 93% RH. A model, named MILIONCAST (an acronym for MILdew on onION foreCAST), was developed based on the data from these controlled environment studies to predict the rate of sporulation in relation to temperature and relative humidity. The accuracy of prediction of sporulation was evaluated by comparing predictions with observations of sporulation on infected plants in pots outdoors. The accuracy of MILIONCAST was compared with the accuracy of existing models based on DOWNCAST. MILIONCAST gave more correct predictions of sporulation than the DOWNCAST models and a random model. All models based on DOWNCAST were more accurate than the random model when compared on the basis of all predictions (including positive and negative predictions), but they gave fewer correct predictions of sporulation than the random model. De Visser's DOWNCAST and ONIMIL improved their accuracy of prediction of sporulation events when the threshold humidity for sporulation was reduced to 92% RH. The temporal pattern of predicted sporulation by MILIONCAST generally corresponded well to the pattern of sporulation observed on the outdoor potted plants at Wellesbourne, UK.

Effective reduced graphene oxide sheets/hierarchical flower-like NiO composites for methanol sensing under high humidity

2018 ◽  
Vol 42 (11) ◽  
pp. 8638-8645 ◽  
Author(s):  
Cecilia A. Zito ◽  
Tarcísio M. Perfecto ◽  
Cristiane S. Fonseca ◽  
Diogo P. Volanti
Keyword(s):  
Graphene Oxide ◽  
Relative Humidity ◽  
Low Temperature ◽  
Reduced Graphene Oxide ◽  
High Humidity ◽  
Reduced Graphene ◽  
Graphene Oxide Sheets ◽  
Sensing Performance

We report the methanol sensing performance of reduced graphene oxide/hierarchical flower-like NiO under 90% of relative humidity and relatively low-temperature.

Milk Films Exposed to High Humidity: Studies with Electron Microscopy and Electrophoresis1,2

1980 ◽  
Vol 43 (1) ◽  
pp. 29-35 ◽  
Author(s):  
R. C. MABESA ◽  
R. T. MARSHALL ◽  
M. E. ANDERSON
Keyword(s):  
Electron Microscopy ◽  
Relative Humidity ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Raw Milk ◽  
Steel Plates ◽  
High Humidity ◽  
Residual Film ◽  
Contact Surfaces ◽  
Scanning Electron

Stainless steel plates, which are similar to milk contact surfaces, were dipped in fresh raw milk. The residual film was dried (37 C and 10% to 20% relative humidity) for 30 min. Treated plates were then exposed to 100% relative humidity for 30 min at 37 C. Scanning electron microscopy revealed splotches of fat on surfaces of dried films and the humidified films had a more aggregated and porous appearance than films that were dried only. The incidence of granulated lactose was greater among humidified samples than among nonhumidified samples. Discontinuous polyacrylamide gel electrophoresis revealed that α- and β-caseins resisted rinsing from plates on which dried films were exposed to 100% relative humidity but not from plates on which films had been dried only.

scholarly journals Efficacy of Beauveria Bassiana Fungus for Boxelder Bug Adult Control, 1996

1997 ◽  
Vol 22 (1) ◽  
pp. 418-419
Author(s):  
James A. Reinert ◽  
Steven J. Maranz ◽  
T. A. Knauf
Keyword(s):  
United States ◽  
Host Plant ◽  
Beauveria Bassiana ◽  
The United States ◽  
Wetting Agent ◽  
High Humidity ◽  
Adult Control ◽  
Filter Papers ◽  
Water Saturated ◽  
Good Coverage

Abstract Boxelder bug is an annual house-hold nuisance pest which leaves its host plant in late fall to seek overwintering sites in and around buildings. It is a pest from coast to coast in the United States and southern Canada. Adults for the study were collected from a heavy seeding big-toothed maple in the landscape at Texas A&M Univ. Res. & Ext. Ctr., Dallas, TX. A maple leaf and 3 seeds as food were dipped in the appropriate dilutions of BioCide-TRFTm (Mycotrol GH-ES) Beauveria bassiana (2.0 X 1013 conidia/qt), and placed on two water saturated filter papers (for high humidity) in each feeding chamber in the lab. Five randomly selected adults were introduced into each 9 cm diam X 15 mm deep plastic feeding chambers labeled for respective treatments in a RCB design with 6 replica-tions. Silwet (0.04%) was added to each treatment as a wetting agent to ensure good coverage. The bugs exposed to different treatments were observed daily for mortality; all dead insects were held for several days to confirm the fungus activity indicated by an expression of mycelia from the joints of dead insects.

Tensile Properties of 7075 Aluminum Alloys Subjected to Pre-Fatigue in Humid Environment

2014 ◽  
Vol 794-796 ◽  
pp. 538-543 ◽  
Author(s):  
Hiroyuki Yamada ◽  
Masaki Tsurudome ◽  
Nagahisa Ogasawara ◽  
Keitaro Horikawa
Keyword(s):  
Aluminum Alloys ◽  
Tensile Properties ◽  
High Humidity ◽  
Fatigue Specimen ◽  
Impact Tests ◽  
Humid Environment ◽  
Fatigue Deformation ◽  
High Humidity Environment ◽  
The Impact ◽  
Humidity Environment

The tensile properties of the quasi-static and the impact tests for 7075 aluminum alloys subjected to pre-fatigue deformation in a humid environment were investigated. An impact tensile test of the pre-fatigue deformed specimens was performed by means of the Split Hopkinson pressure bar method. Within the authors set of experiments, the flow stress in both the quasi-static and the impact tests was unaffected by the pre-fatigue deformation. On the other hand, it was shown that the ductility of the pre-fatigue specimen was slightly lower than that of the non-fatigue specimen. Additionally, the pre-fatigue specimen in a high-humidity environment had a lower ductility than in a low-humidity environment. The ductility of the quasi-static test was decreased as compared with the impact test. It is thought that the ductility loss occurred due to changes in the microstructure, such as dislocations caused by the presence of hydrogen in the specimen due to pre-fatigue deformation in a high-humidity environment.

Synchronous and high frequency germination of interior spruce somatic embryos following partial drying at high relative humidity

1990 ◽  
Vol 68 (5) ◽  
pp. 1086-1090 ◽  
Author(s):  
D. R. Roberts ◽  
B. C. S. Sutton ◽  
B. S. Flinn
Keyword(s):  
Relative Humidity ◽  
Somatic Embryos ◽  
Low Frequency ◽  
High Relative Humidity ◽  
Zygotic Embryos ◽  
Interior Spruce ◽  
Half Strength ◽  
Abnormal Pattern ◽  
Time Required ◽  
Water Saturated

The germination of mature somatic embryos of interior spruce was limited by the low frequency of root emergence. In addition, development was abnormal, since elongation and greening of the hypocotyl and cotyledons preceded root emergence by 1–2 weeks. Pretreatment of the embryos on water-saturated Kim-paks increased the frequency of root emergence but did not alter the abnormal pattern of germination. Somatic embryos do not survive desiccation at room humidity, but partial drying at high humidity promoted germination up to 90%. Furthermore, this treatment decreased the time required for root emergence such that elongation of the root and hypocotyl–cotyledon was synchronized over a period of 5–6 days. This germination closely resembled that of excised zygotic embryos. Drying over a range of humidities indicated that humidities of 81% and lower were lethal to the embryos, whereas germination was enhanced following treatment at humidities greater than 95% relative to untreated controls. The best germination and root elongation occurred on one-half strength basal media containing 2–3.4% sucrose. Of the plantlets derived from treated embryos, 50% survived transfer to soil compared with only 5% of the untreated controls. Key words: conifers, desiccation, germination, high relative humidity, partial drying, somatic embryogenesis, spruce.

Measurement and Characterization of the Moisture-Induced Properties of ACF Package

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Ji-Young Yoon ◽  
Ilho Kim ◽  
Soon-Bok Lee
Keyword(s):  
Diffusion Coefficient ◽  
Relative Humidity ◽  
Moisture Content ◽  
Chemical Interaction ◽  
Transient State ◽  
Length Change ◽  
Experimental Results ◽  
Moisture Movement ◽  
Humid Environment ◽  
Swelling Coefficient

This study is to observe the exact behavior of anisotropic conductive adhesion (ACF) package under humid environments by obtaining the moisture-induced properties such as diffusion coefficient (the rate of moisture movement into the materials), saturated moisture content (the maximum absorbed quantity), and swelling coefficient (length change due to the chemical interaction). So the experiments were performed to get the moisture-induced properties of ACF and FR4 using newly developed method at various temperature and relative humidity conditions. Experimental results showed that the diffusion coefficient of ACF and FR4 follows Arrhenius’ equation very well, and the saturated moisture content of them follows Henry’s law, which means linear relationship between saturated moisture content and relative humidity, but the saturated moisture content of ACF is influenced by temperature as well as relative humidity. And the swelling coefficient of ACF and FR4 increases with temperature. Especially in the case of ACF, it shows the dramatic degradation due to Tg (glass transition temperature) at nearby 85°C. Finally, as using these experimental results, the behavior of the ACF package under humid environment is predicted through finite element simulation. When wetness defined by moisture content over saturated moisture content changes from 0 to 0.9, the center of the ACF package is subject to compression and the edge of the ACF package is subject to tension in the case of transient state. After all, because the edge of the ACF package is very weak due to bending moment, the failure is easy to occur under humid environment.

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