scholarly journals Control of Humidity in Small Controlled-environment Chambers using Glycerol-Water Solutions

1992 ◽  
Vol 2 (1) ◽  
pp. 52-54 ◽  
Author(s):  
Charles F. Forney ◽  
David G. Brandl
Keyword(s):  
Relative Humidity ◽  
Specific Gravity ◽  
Flow Rate ◽  
Water Solution ◽  
Solution Temperature ◽  
Controlled Environment ◽  
Glycerol Water ◽  
Water Solutions ◽  
Temperature And Pressure ◽  
The Relationship

Solutions of glycerol and water provide a convenient and inexpensive system to control the relative humidity (RH) in small controlled-environment chambers. The relationship between the specific gravity (SG) of a glycerol-water solution and its equilibrium RH is described by the equation SG = [-0.189 (RH) + 19.9]0.0806. Gas can be humidified by bubbling it through jars containing solutions of glycerol-water with the desired equilibrium RH. The effects of flow rate, volume of solution, temperature, and pressure on the equilibrium RH are discussed.

The Use Of 222Rn as a Flow Path Monitor for Studies of Radionuclide Transport in Fissures

1981 ◽  
Vol 6 ◽  
Author(s):  
J. Hines ◽  
D. Cohen ◽  
S. Fried ◽  
A. M. Friedman
Keyword(s):  
Field Test ◽  
Flow Rate ◽  
Water Solution ◽  
Diffusion Profile ◽  
Breakthrough Curves ◽  
Flow Path ◽  
Radionuclide Transport ◽  
Radionuclide Concentration ◽  
Water Solutions ◽  
Flat Surfaces

ABSTRACTA technique has been developed using 222Rn as a flow path monitor. Its principle advantage over other radiotracers or dyes is that while the Kd of Rn gas in water solution is zero and hence follows the water path, its 210Pb daughter is retained strongly by rock. The immobilized 210Pb is not subject to diffusion, an important consideration in the proposed Nevada Field Test. To evaluate the technique, a series of laboratory scale experiments have been performed. Artificial fissures consisting of glass plates and prepared flat surfaces were coupled to insure well characterized fissures. Water solutions of radiotracer were metered through these fissures and the discharge monitored to produce breakthrough curves as a function of flow rate. The rock surfaces were analysed for radionuclide concentration and the rock sectioned for diffusion profile into the rock.

scholarly journals Storage Temperature and Moisture Content Affect Respiration and Survival of Ranunculus asiaticus Dry Tuberous Roots

HortScience ◽  
2011 ◽  
Vol 46 (11) ◽  
pp. 1523-1527 ◽  
Author(s):  
Christopher B. Cerveny ◽  
William B. Miller ◽  
Alan G. Taylor
Keyword(s):  
Relative Humidity ◽  
Moisture Content ◽  
Storage Temperature ◽  
Glycerol Water ◽  
Water Solutions ◽  
Tuberous Roots ◽  
Ranunculus Asiaticus ◽  
Flow Through ◽  
Closed Systems

Ranunculus asiaticus (L.) is an ornamental geophyte with some commercial production challenges presumed to be related to the storage of its desiccation tolerant tuberous roots (TRs). We investigated the influence of temperature and relative humidity during storage on viability of R. asiaticus TRs. The TRs were stored in specialized chambers for controlling relative humidity under flow-through or closed systems. In the flow-through system, air was bubbled through glycerol–water solutions to create relative humidities of 20%, 40%, 60%, 80%, or 100% and then passed through storage chambers held at 5, 20, or 35 °C for up to 20 weeks. In closed storage, tissue was equilibrated to a given moisture content (fresh basis) at 15 °C by suspending TRs over glycerol–water solutions (35%, 60%, or 85% relative humidity) with fans to circulate air. These containers were closed for 4 weeks and then tissue was transferred to sealed jars for up to 17 weeks at 5 or 25 °C. In both systems, TRs held with elevated temperature and relative humidity had the largest decrease in percent survival when planted after storage. Flow-through storage gave greater variability in TRs moisture content than closed storage. Tuberous roots at 25 °C had higher respiration rates than at 5 °C under closed storage; elevated moisture content also led to increased respiration. From these results it can be concluded that R. asiaticus dry TRs should be stored cool and dry for long-term viability.

scholarly journals The effects of ambient conditions on the calibration of air flow plate standards

2013 ◽  
Vol 17 (5) ◽  
pp. 1517-1520
Author(s):  
Qian Miao ◽  
Rong-Chao Yang ◽  
Qing Zhang ◽  
Jing Cheng ◽  
Jia-Cun Shao ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Flow Rate ◽  
Atmospheric Pressure ◽  
Volume Flow Rate ◽  
Air Flow ◽  
Volume Flow ◽  
Calibration Data ◽  
Ambient Conditions ◽  
Numerical Examples ◽  
The Relationship

The volume flow rate measured by air flow plate is influenced by the ambient conditions during the calibration. A series of numerical examples are conducted for the relationship and the outcomes demonstrated that the calibration is quite sensitive to the atmospheric pressure and the ambient temperature, but insensitive to relative humidity. The experiment model has been applied to calibration results with wide ranging ambient conditions. In conclusion, the results of this study demonstrate the benefits to calibration data of minimizing the effects of ambient conditions.

Flash Point and Specific Gravity of Ethanol-Water-Sugar Solutions

1978 ◽  
Vol 61 (3) ◽  
pp. 605-608
Author(s):  
Duane H Strunk ◽  
Jack W Hamman ◽  
Jacob Steimel ◽  
Arthur A Andreasen
Keyword(s):  
Hydrogen Bonding ◽  
Specific Gravity ◽  
Vapor Pressure ◽  
Flash Point ◽  
Sugar Concentration ◽  
Water Solutions ◽  
Air Interface ◽  
The Relationship

Abstract Flash points and specific gravities were determined for ethanol-water-sugar solutions in the concentration range normally found in liqueurs. Flash point determinations were made using a Tag closed cup tester. Increasing the proof of ethanol-water solutions from 60 to 120° lowers the flash point from 32.8 to 24.4°C. The flash point is also lowered by the addition of sugar, e.g., from 32.8 to 25.0°C at 60° proof when the sugar concentration is increased from 0 to 40%. This is due largely to the sugar replacing a portion of the water, and to hydrogen bonding between the sugar and water, thereby effectively increasing the proof and vapor pressure of the ethanol at the air interface. A graph is presented showing the relationship between the concentration of sugar and the specific gravity for different proof samples, which can be used to estimate the per cent sugar in a liqueur when the proof and specific gravity are known. When the sugar concentration and proof are known, the flash point can be estimated.

scholarly journals A SIMPLE METHOD TO CONTROL HUMIDITY IN SMALL EXPERIMENTAL CHAMBERS

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1105e-1105
Author(s):  
Charles F. Forney ◽  
David G. Brandl
Keyword(s):  
Water Solution ◽  
Pure Water ◽  
Glycerol Water ◽  
Simple Method ◽  
Horticultural Crops ◽  
Flow Through ◽  
Closed Systems ◽  
Relationship Of ◽  
The Relationship ◽  
And Storage

Humidity is an important component of the enviornment that influences the growth, development and storage life of most horticultural crops. A method to control relative humidity (RH) in experimental chambers using solutions of glycerol-water has been developed. A constant RH can be established and maintained by bubbling air through a glycerol-water solution of known water content. The air rapidly reaches equilibrium with the glycerol-water solution producing the desired RH. The relationship of the specific gravity (SG) of glycerol-water solutions and the corresponding equilibrium RH was determined. Any desired RH can be produced by using solutions of the appropriate SG ranging from 100% with pure water (SG 25/25 = 1.000) to 0% with pure glycerol (SG 25/25 = 1.261) This system can be used in flow through systems by bubbling the incoming air through the solution or in closed systems by circulating air through the solution and the chamber. Multiple jars of solution can be used for more precise RH control. The effects that temperature and atmospheric pressure in the jars have on the equilibrium RH will be discussed.

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.

scholarly journals Neural network-based modeling of the number of microbubbles generated with four circulation factors in cardiopulmonary bypass

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Satoshi Miyamoto ◽  
Zu Soh ◽  
Shigeyuki Okahara ◽  
Akira Furui ◽  
Taiichi Takasaki ◽  
...  
Keyword(s):  
Cardiopulmonary Bypass ◽  
Flow Rate ◽  
Neurological Complications ◽  
Estimation Accuracy ◽  
Model Parameters ◽  
Perfusion Flow ◽  
Postsurgical Complication ◽  
Tenfold Cross Validation ◽  
Suction Flow ◽  
The Relationship

AbstractThe need for the estimation of the number of microbubbles (MBs) in cardiopulmonary bypass surgery has been recognized among surgeons to avoid postoperative neurological complications. MBs that exceed the diameter of human capillaries may cause endothelial disruption as well as microvascular obstructions that block posterior capillary blood flow. In this paper, we analyzed the relationship between the number of microbubbles generated and four circulation factors, i.e., intraoperative suction flow rate, venous reservoir level, continuous blood viscosity and perfusion flow rate in cardiopulmonary bypass, and proposed a neural-networked model to estimate the number of microbubbles with the factors. Model parameters were determined in a machine-learning manner using experimental data with bovine blood as the perfusate. The estimation accuracy of the model, assessed by tenfold cross-validation, demonstrated that the number of MBs can be estimated with a determinant coefficient R2 = 0.9328 (p < 0.001). A significant increase in the residual error was found when each of four factors was excluded from the contributory variables. The study demonstrated the importance of four circulation factors in the prediction of the number of MBs and its capacity to eliminate potential postsurgical complication risks.

scholarly journals Spatiotemporal Variation of the Burned Area and Its Relationship with Climatic Factors in Central Kazakhstan

2021 ◽  
Vol 13 (2) ◽  
pp. 313
Author(s):  
Yongfang Xu ◽  
Zhaohui Lin ◽  
Chenglai Wu
Keyword(s):  
Soil Moisture ◽  
Relative Humidity ◽  
Central Asia ◽  
Climatic Factors ◽  
Spatiotemporal Variation ◽  
Lower Atmosphere ◽  
Burned Area ◽  
Circulation Index ◽  
Precipitation Anomalies ◽  
The Relationship

Central Asia is prone to wildfires, but the relationship between wildfires and climatic factors in this area is still not clear. In this study, the spatiotemporal variation in wildfire activities across Central Asia during 1997–2016 in terms of the burned area (BA) was investigated with Global Fire Emission Database version 4s (GFED4s). The relationship between BA and climatic factors in the region was also analyzed. The results reveal that more than 90% of the BA across Central Asia is located in Kazakhstan. The peak BA occurs from June to September, and remarkable interannual variation in wildfire activities occurs in western central Kazakhstan (WCKZ). At the interannual scale, the BA is negatively correlated with precipitation (correlation coefficient r = −0.66), soil moisture (r = −0.68), and relative humidity (r = −0.65), while it is positively correlated with the frequency of hot days (r = 0.37) during the burning season (from June to September). Composite analysis suggests that the years in which the BA is higher are generally associated with positive geopotential height anomalies at 500 hPa over the WCKZ region, which lead to the strengthening of the downdraft at 500 hPa and the weakening of westerlies at 850 hPa over the region. The weakened westerlies suppress the transport of water vapor from the Atlantic Ocean to the WCKZ region, resulting in decreased precipitation, soil moisture, and relative humidity in the lower atmosphere over the WCKZ region; these conditions promote an increase in BA throughout the region. Moreover, the westerly circulation index is positively correlated (r = 0.53) with precipitation anomalies and negatively correlated (r = −0.37) with BA anomalies in the WCKZ region during the burning season, which further underscores that wildfires associated with atmospheric circulation systems are becoming an increasingly important component of the relationship between climate and wildfire.

scholarly journals Effect of Fluid Flow on the Corrosion Performance of as-Cast and Heat-Treated Nickel Aluminum Bronze Alloy (UNS C95800) in Saline Solution

2021 ◽  
Vol 2 (1) ◽  
pp. 61-77
Author(s):  
Hamid Reza Jafari ◽  
Ali Davoodi ◽  
Saman Hosseinpour
Keyword(s):  
Corrosion Resistance ◽  
Corrosion Behavior ◽  
Flow Rate ◽  
Solution Temperature ◽  
Aluminum Bronze ◽  
Nickel Aluminum ◽  
Nacl Solution ◽  
Flow Conditions ◽  
Heat Treated ◽  
Nickel Aluminum Bronze

In this work, the corrosion behavior and surface reactivity of as-cast and heat-treated nickel aluminum bronze casting alloy (UNS C95800) in 3.5 wt% NaCl solution is investigated under stagnant and flow conditions. Increasing flow rate conditions are simulated using a rotating disk electrode from 0 to 9000 revolutions per minute (rpm). Optical micrographs confirm the decrease in the phase fraction of corrosion-sensitive β phase in the microstructure of C95800 after annealing, which, in turn, enhances the corrosion resistance of the alloy. Electrochemical studies including open circuit potentiometry, potentiodynamic polarization, and electrochemical impedance spectroscopy are performed to assess the effect of flow rate and heat treatment on the corrosion of samples at 25 and 40 °C in 3.5 wt% NaCl solution. For both as-cast and heat-treated samples, increasing the flow rate (i.e., electrode rotating rate) linearly reduces the corrosion resistance, indicating that the metal dissolution rate is significantly affected by hydrodynamic flow. Increasing the solution temperature negatively impacts the corrosion behavior of the as-cast and heat-treated samples at all flow conditions.

Influence of Non-Equilibrium Fluid Properties During Fogging on Intake Duct and Compressor Characteristics

2017 ◽  
Author(s):  
Christoph Günther ◽  
Franz Joos
Keyword(s):  
Relative Humidity ◽  
Gas Turbine ◽  
Thermophysical Properties ◽  
Ambient Air ◽  
Compressor Stage ◽  
Compression Process ◽  
Fluid Properties ◽  
Temperature And Pressure ◽  
Gas Turbine Compressor ◽  
Non Equilibrium

This study reports on numerically calculated thermophysical properties of air passing through a gas turbine compressor after passage through an intake duct affected by wet compression. Case of reference is unaffected ambient air (referenced to as dry scenario) passing through intake duct and compressor. Furthermore, ambient air cooled down by (overspray) fogging (referenced to as wet scenarios) was considered. Acceleration at the end of intake duct causing reduction of static temperature and pressure results in supersaturated fluid properties at inlet to gas turbine compressor. These supersaturated fluid properties are non-equilibrium with saturation level above relative humidity of φ = 1. Entrance of supersaturated fluid into gas turbine compressor can result in condensation within first compressor stage. At the same time delayed impact of evaporative cooling influences compression process.

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