Growth rate of an ice crystal in subcooled pure water

AIChE Journal ◽  
1977 ◽  
Vol 23 (3) ◽  
pp. 294-303 ◽  
Author(s):  
Joshy P. Kallungal ◽  
Allen J. Barduhn
Keyword(s):  
Growth Rate ◽  
Pure Water ◽  
Ice Crystal

Inhibition of Blockage by Ice Crystal in Water in a Micro-Channel by Using Antifreeze Protein

2010 ◽  
Author(s):  
Yoshimichi Hagiwara ◽  
Yosuke Ohnishi ◽  
Daichi Yamamoto
Keyword(s):  
Flow Rate ◽  
Pure Water ◽  
Antifreeze Protein ◽  
The Other ◽  
Micro Channel ◽  
Ice Crystal ◽  
Protein Solution ◽  
Local Cooling ◽  
Solution Flow ◽  
Temperature Changes

Experiments have been conducted into the freezing of water flow and the aqueous solution flow of winter flounder antifreeze protein in a micro-channel of 0.15mm in height, 1.2mm in width and 21mm in length. The local temperature is measured with a sheathed thermocouple of 0.1mm in diameter. Nearly flat interfaces, parallel to the cooling sidewall of the channel, are observed in the case of pure water regardless of flow rate. On the other hand, serrated interfaces are observed in the case of protein solution flow regardless of flow rate. The decreasing rate of the temperature changes when the interface reaches the thermocouple. Around this instant, a slight increase in the temperature is observed due to supercooling release. In the case of local cooling, the interface becomes more serrated as the flow rate increases. This is because the interaction between the interface and the protein continuously approaching the interface due to the flow occurs more frequently with an increase in the flow rate.

Cleaning and Oxidation of Heavily Doped Si Surfaces

1992 ◽  
Vol 259 ◽  
Author(s):  
T. Yasaka ◽  
S. Uenaga ◽  
H. Yasutake ◽  
M. Takakura ◽  
S. Miyazaki ◽  
...  
Keyword(s):  
Growth Rate ◽  
Steric Hindrance ◽  
Photoelectron Spectroscopy ◽  
Oxidation Rate ◽  
Electron Tunneling ◽  
Pure Water ◽  
Native Oxide ◽  
Layer By Layer ◽  
Surface Electric Field ◽  
Heavily Doped

ABSTRACTHF-treated Si surfaces and the oxidation kinetics in pure water or in clean room air have systematically been studied by x-ray photoelectron spectroscopy (XPS). The oxidation of heavily-doped n-type Si appears to proceed parallel to the surface, resulting in the layer-by-layer oxidation. The oxide growth rate in pure water for heavily-doped n-type Si is significantly higher than that of heavily-doped ptype Si. This is explained by the electron tunneling from the Si conduction band to adsorbed O2 molecules to form the O2 state. O2 ions easily decompose and induce a surface electric field, enhancing the oxidation rate. The growth rate of native oxide on heavily-doped n-type Si is less sensitive to the crystallographic orientations than the case of lightly doped Si where the steric hindrance against oxygen molecules significantly lowers the oxidation rate of the (110) and (111) surfaces. We suggest that the decomposed oxygen can penetrate into Si without steric hindrance. It is also found that the oxidation of heavily-doped n-type Si in pure water is effectively suppressed by adding a small amount (10 ∼ 3600 ppm) of HCI.

Measurements of Growth Rates of an Ice Crystal from Supercooled Heavy Water under Microgravity Conditions: Basal Face Growth Rate and Tip Velocity of a Dendrite

2011 ◽  
Vol 115 (27) ◽  
pp. 8739-8745 ◽  
Author(s):  
Etsuro Yokoyama ◽  
Izumi Yoshizaki ◽  
Taro Shimaoka ◽  
Takehiko Sone ◽  
Tatsuo Kiyota ◽  
...  
Keyword(s):  
Growth Rate ◽  
Heavy Water ◽  
Growth Rates ◽  
Ice Crystal ◽  
Basal Face ◽  
Microgravity Conditions ◽  
Tip Velocity

Prediction of SCC growth rate in high temperature pure water under residual stress field

2003 ◽  
Vol 2003 (0) ◽  
pp. 757-758
Author(s):  
Tatsuya Kubo ◽  
Mikiro Itow ◽  
Masaaki Kikuchi ◽  
Norihiko Tanaka
Keyword(s):  
Residual Stress ◽  
Growth Rate ◽  
High Temperature ◽  
Stress Field ◽  
Pure Water ◽  
Residual Stress Field

Prediction of SCC growth rate in high temperature pure water

2004 ◽  
Vol 2004 (0) ◽  
pp. 185-186
Author(s):  
Tatsuya Kubo ◽  
Mikiro Itow ◽  
Masaaki Kikuchi ◽  
Norihiko Tanaka
Keyword(s):  
Growth Rate ◽  
High Temperature ◽  
Pure Water

scholarly journals Towards the Understanding of Ice Crystal-graupel Collision Charging in Thunderstorm Electrification

2018 ◽  
Author(s):  
Yuanping He ◽  
Boyan Gu ◽  
Daizhou Zhang ◽  
Weizhen Lu ◽  
Chuck Wah Yu ◽  
...  
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Charge Separation ◽  
Thermal Equilibrium ◽  
Chemical Potential ◽  
Surface Tension Gradient ◽  
Rate Theory ◽  
Ice Crystal ◽  
Charge Migration ◽  
Relative Growth

Thunderstorm electrification has been studied for hundreds of years. Several mechanisms have been proposed to elucidate the electrification, including convective charging, inductive precipitation charging, and ice crystal-graupel collision charging. Field observations and model studies have demonstrated the vital roles that graupel and ice crystals play in the electrification, but the mechanism of the collision charging is still unclear. The fundamental essence of relative growth rate theory used for explaining the tripole charge structure in thunderclouds also needs a further exploration. We analyze the processes of ice crystal-graupel collision charging from charge migration inside hydrometeors to charge separation between two hydrometeors. The driving effects of temperature gradient and chemical potential gradient in charge migration are clarified, as well as the applicability of the relative growth rate theory, thermoelectric effect and surface tension gradient in different humidities. Based on the understanding from these electrification mechanisms, we propose that the essence of charge separation is driven by non-thermal equilibrium, and future studies on thunderstorm electrification should focus on the dynamical non-thermal equilibrium of cloud particles.

Effect of Coolant Temperature on Desalination Process via Progressive Freeze Concentration

2014 ◽  
Vol 695 ◽  
pp. 443-446 ◽  
Author(s):  
Ab. Hamid Farah Hanim ◽  
A.Rahim Norfatiha ◽  
Norzita Ngadi ◽  
Zaki Yamani Zakaria ◽  
Jusoh Mazura
Keyword(s):  
System Performance ◽  
New Technologies ◽  
Pure Water ◽  
Coolant Temperature ◽  
Clean Water ◽  
Ice Crystal ◽  
Freeze Concentration ◽  
Salinity Reduction ◽  
The World ◽  
Crystal Block

The world is still suffering from a shortage of clean water supply and the problem is expected to become more serious in the future. Consequently, researchers have been trying to find the best solution to address this problem by introducing new desalination technologies that are able to accommodate the demand for clean water which is increasing from time to time. One of the new technologies introduced is the desalination of seawater through freeze concentration. In this study, progressive freeze concentration (PFC) is implemented to produce pure water in the form of ice crystal block and leave behind a higher concentration solution. The effect of coolant temperature was investigated and the efficiency of the system was reviewed based on the value of effective partition constant, K which is defined by the ratio of solute in ice and liquid phase. The low value of K leads to the best efficiency for the system. Apart from that, the efficiency, E% and salinity reduction were also calculated in order to determine the system performance.

Wind-induced growth of water waves

1982 ◽  
Vol 123 ◽  
pp. 425-442 ◽  
Author(s):  
H. Mitsuyasu ◽  
T. Honda
Keyword(s):  
Growth Rate ◽  
Water Waves ◽  
Friction Velocity ◽  
Wind Wave ◽  
Wind Waves ◽  
Pure Water ◽  
Wave Flume ◽  
Wind Speeds ◽  
Wind Profiles ◽  
The Waves

Spatial growth of mechanically generated water waves under the action of wind has been measured in a laboratory wind-wave flume both for pure water and for water containing a surfactant (sodium lauryl sulphate, concentration 2.6 × 10−2%). I n the latter case, no wind waves develop on the surface of the mechanically generated waves as well as on the still water surface for wind speeds up to U10≈ 15 m/s, where U10 is the wind velocity at the height Z = 10 m. Therefore we can study the wind-induced growth of monochromatic waves without the effects of co-existing short wind waves. The mechanically generated waves grew exponentially under the action of the wind, with fetch in both cases. The measured growth rate β for the pure water can be fitted by β/f = 0.34(U*/C)2 0.1 [lsime ] U*/C [lsime ] 1.0, where f is the frequency of the waves, C is the corresponding phase velocity, and U, is the friction velocity obtained from vertical wind profiles. The effect of the wave steepness H/L on the dimensionless growth rate β/f is not clear, but seems to be small. For water containing the surfactant, the measured growth rate is smaller than that for pure water, but the friction velocity of the wind is also small, and the above relation between β/f and U*/C holds approximately if the measured friction velocity U* is used for the relation.

On the Growth of Ice in Aqueous Solutions Contained in Capillaries

1967 ◽  
Vol 22 (6) ◽  
pp. 895-901 ◽  
Author(s):  
H. R. Pruppacher
Keyword(s):  
Growth Rate ◽  
Aqueous Solutions ◽  
Freezing Point ◽  
Pure Water ◽  
Solution Interface ◽  
Dilute Aqueous Solutions ◽  
The One ◽  
Rate Of Dissipation ◽  
Common Anion ◽  
Bromide Solutions

The growth rate of ice in supercooled water and in dilute aqueous solutions of various salts which dissociate in water into univalent ions was studied. The solutions contained in polyethylene tubes of small bore had concentrations between 10-6 and 10-1 moles liter-1 and were investigated at bath supercoolings between 1° and 15°C. The growth rate of ice which in pure water was found to vary approximately with the square of the bath supercooling was affected in a systematic manner by the type and concentration of the salt in solution. At salt concentrations smaller than 5 × 10-2 moles liter-1 most salts did not affect the growth rate. However, the fluorides were found to increase the growth rate over and above the one in pure water. At concentrations larger than 5 × 10-2 moles liter-1 all the salts reduced the growth rate of ice below the one in pure water. By comparing solutions of salts with common anion it was found that at a particular bath supercooling and salt concentration the growth rate of ice was reduced most in lithium solutions and least in cesium and ammonium solutions. By comparing solutions of salts with common cation it was found that the growth rate of ice was reduced most in fluoride solutions and least in bromide solutions. It was concluded that in solutions with salt concentrations larger than 5 × 10-2 moles liter-1 the rate of dissipation of latent heat which controls the growth rate of ice is affected in a systematic manner by the freezing point lowering effects which result from pure mass transfer conditions prevailing at the ice-solution interface of a stagnant system. Some features of the observed growth rates are discussed in terms of the effect of dissolved salts on the growth forms of ice in aqueous solutions.

Progressive Freeze Concentration for Wastewater Treatment from Food Industry

2019 ◽  
Vol 797 ◽  
pp. 55-64 ◽  
Author(s):  
Farah Hanim Ab Hamid ◽  
Siti Nurajjar Jami
Keyword(s):  
Wastewater Treatment ◽  
Food Industry ◽  
Pure Water ◽  
Coolant Temperature ◽  
Wastewater Sample ◽  
Ice Crystal ◽  
K Value ◽  
Freeze Concentration ◽  
Simulated Wastewater ◽  
Crystal Block

Crystallization technique is one of the potential techniques to deal with wastewater treatment. In this work, progressive freeze concentration (PFC) technique was studied for its effectiveness in wastewater treatment from food industry. In PFC, pure water is produced in the form of ice crystal block and leave behind a higher concentration solution. The effect of coolant temperature and stirring speed on the effective partition constant (K) and solute recovery (Y) were investigated. Glucose solution was used as simulated wastewater sample. The best conditions were found at the moderate coolant temperature of -10°C and maximum stirring speed of 500 rpm, resulted in the lowest K value and highest Y, lead to the highest efficiency on the wastewater treatment.

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