Thermodynamic Theory and Experimental Validation of a Multiphase Isochoric Freezing Process

2019 ◽  
Vol 141 (8) ◽  
Author(s):  
Matthew J. Powell-Palm ◽  
Justin Aruda ◽  
Boris Rubinsky
Keyword(s):  
First Principles ◽  
Experimental Validation ◽  
Freezing Point ◽  
Physiological Saline ◽  
Physiological Solution ◽  
Freezing Process ◽  
Hypertonic Solution ◽  
Chemical Additives ◽  
Biological Matter ◽  
High Concentrations

Freezing of the aqueous solutions that comprise biological materials, such as isotonic physiological saline, results in the formation of ice crystals and the generation of a hypertonic solution, both of which prove deleterious to biological matter. The field of modern cryopreservation, or preservation of biological matter at subfreezing temperatures, emerged from the 1948 discovery that certain chemical additives such as glycerol, known as cryoprotectants, can protect cells from freeze-related damage by depressing the freezing point of water in solution. This gave rise to a slew of important medical applications, from the preservation of sperm and blood cells to the recent preservation of an entire liver, and current cryopreservation protocols thus rely heavily on the use of additive cryoprotectants. However, high concentrations of cryoprotectants themselves prove toxic to cells, and thus there is an ongoing effort to minimize cryoprotectant usage while maintaining protection from ice-related damage. Herein, we conceive from first principles a new, purely thermodynamic method to eliminate ice formation and hypertonicity during the freezing of a physiological solution: multiphase isochoric freezing. We develop a comprehensive thermodynamic model to predict the equilibrium behaviors of multiphase isochoric systems of arbitrary composition and validate these concepts experimentally in a simple device with no moving parts, providing a baseline from which to design tailored cryopreservation protocols using the multiphase isochoric technique.

On intravenous infusions for blood loss

1927 ◽  
Vol 23 (3) ◽  
pp. 350-350
Author(s):  
N. D. Perumov
Keyword(s):  
Blood Loss ◽  
Saline Solution ◽  
Physiological Saline ◽  
Physiological Solution ◽  
Single Infusion ◽  
Intravenous Infusions ◽  
Physiological Saline Solution

The author believes that the infusion of gummy-arabic solution and the drip method of intravenous infusions of physiological saline solution are approximately equivalent and superior to a simple single infusion of physiological solution.

scholarly journals The faint young Sun problem revisited with a 3-D climate–carbon model – Part 1

2014 ◽  
Vol 10 (2) ◽  
pp. 697-713 ◽  
Author(s):  
G. Le Hir ◽  
Y. Teitler ◽  
F. Fluteau ◽  
Y. Donnadieu ◽  
P. Philippot
Keyword(s):  
Radiative Forcing ◽  
General Circulation ◽  
Freezing Point ◽  
Climatic Factors ◽  
General Circulation Models ◽  
Companion Paper ◽  
One Dimensional ◽  
Carbon Dioxide Concentrations ◽  
Wide Range ◽  
High Concentrations

Abstract. During the Archaean, the Sun's luminosity was 18 to 25% lower than the present day. One-dimensional radiative convective models (RCM) generally infer that high concentrations of greenhouse gases (CO2, CH4) are required to prevent the early Earth's surface temperature from dropping below the freezing point of liquid water and satisfying the faint young Sun paradox (FYSP, an Earth temperature at least as warm as today). Using a one-dimensional (1-D) model, it was proposed in 2010 that the association of a reduced albedo and less reflective clouds may have been responsible for the maintenance of a warm climate during the Archaean without requiring high concentrations of atmospheric CO2 (pCO2). More recently, 3-D climate simulations have been performed using atmospheric general circulation models (AGCM) and Earth system models of intermediate complexity (EMIC). These studies were able to solve the FYSP through a large range of carbon dioxide concentrations, from 0.6 bar with an EMIC to several millibars with AGCMs. To better understand this wide range in pCO2, we investigated the early Earth climate using an atmospheric GCM coupled to a slab ocean. Our simulations include the ice-albedo feedback and specific Archaean climatic factors such as a faster Earth rotation rate, high atmospheric concentrations of CO2 and/or CH4, a reduced continental surface, a saltier ocean, and different cloudiness. We estimated full glaciation thresholds for the early Archaean and quantified positive radiative forcing required to solve the FYSP. We also demonstrated why RCM and EMIC tend to overestimate greenhouse gas concentrations required to avoid full glaciations or solve the FYSP. Carbon cycle–climate interplays and conditions for sustaining pCO2 will be discussed in a companion paper.

scholarly journals Enhancing the Lubricity of Gas-to-Liquid (GTL) Paraffinic Kerosene: Impact of the Additives on the Physicochemical Properties

2020 ◽  
Author(s):  
Hani Ababnah ◽  
Nasr Mohamed ◽  
Hanif Choudhury ◽  
Lei Lei Zhang ◽  
Rafiqul Gani ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Physicochemical Properties ◽  
Negative Impact ◽  
Freezing Point ◽  
Ethyl Oleate ◽  
Heat Content ◽  
Wear Scar Diameter ◽  
Dual Nature ◽  
Fuel Jet ◽  
High Concentrations

Abstract Synthetic paraffinic kerosene (SPK) is an ultra-clean fuel with low aromatic content and negligible quantities of sulfur compounds . Although, SPK has a good potential to replace the conventional fuel Jet A-1 , it also has some deficiencies. One of them is the low lubricity compared to its conventional counterpart Jet A-1. To improve the lubricity of SPK, three selected additives have been mixed with SPK at different concentrations. The lubricity of the samples was determined experimentally and the samples that meet the industry specifications have been studied further. The effect of the additives on the physicochemical properties, such as, density, flash point, freezing point, viscosity, and heat content, were investigated. Linoleic acid was found to be an excellent lubricity improver even at a very low concentration and its negative impact on the other physicochemical properties was found to be insignificant. Ethyl oleate also demonstrated significant improvement in lubricity at low concentrations but had a negative impact on the fuel’s freezing point at high concentrations. Quinoline, at high concentrations, elevated the blend’s freezing point above the acceptable limits. In parallel to the experimental campaign, a pre-existing mathematical modelling tool was utilized to predict the properties of interest. The lubricity model was successfully introduced into the mathematical model in order to improve the capabilities of the model. Linoleic acid sample showed the best improvement in lubricity of SPK with wear scar diameter of 4 17 μm; well below the ASTM D7566 maximum limit of 850µm. The dual nature of this study facilitated the optimization of the physicochemical properties of the fuel samples.

scholarly journals First-Principles Design of Refractory High Entropy Alloy VMoNbTaW

Entropy ◽  
2018 ◽  
Vol 20 (12) ◽  
pp. 965 ◽  
Author(s):  
Shumin Zheng ◽  
Shaoqing Wang
Keyword(s):  
Elastic Properties ◽  
First Principles ◽  
High Entropy Alloy ◽  
Low Density ◽  
High Entropy ◽  
System A ◽  
Small Influence ◽  
High Concentrations ◽  
General Guidance ◽  
Selection Of

The elastic properties of seventy different compositions were calculated to optimize the composition of a V–Mo–Nb–Ta–W system. A new model called maximum entropy approach (MaxEnt) was adopted. The influence of each element was discussed. Molybdenum (Mo) and tungsten (W) are key elements for the maintenance of elastic properties. The V–Mo–Nb–Ta–W system has relatively high values of C44, bulk modulus (B), shear modulus (G), and Young’s modulus (E), with high concentrations of Mo + W. Element W is brittle and has high density. Thus, low-density Mo can substitute part of W. Vanadium (V) has low density and plays an important role in decreasing the brittleness of the V–Mo–Nb–Ta–W system. Niobium (Nb) and tantalum (Ta) have relatively small influence on elastic properties. Furthermore, the calculated results can be used as a general guidance for the selection of a V–Mo–Nb–Ta–W system.

Freezing Point Determination in Immature Stages of Insects

1964 ◽  
Vol 96 (1-2) ◽  
pp. 158-158 ◽  
Author(s):  
C. R. Sullivan ◽  
G. W. Green
Keyword(s):  
Cold Hardiness ◽  
Freezing Point ◽  
Visual Observation ◽  
Freezing Process ◽  
Immature Stages ◽  
Filter Paper Disc ◽  
Recording Potentiometer ◽  
Binocular Microscope ◽  
The Moment ◽  
Freezing Chamber

Conventional and modified methods of obtaining supercooling points of immature stages of insects have been utilized in studies of the cold-hardiness of the European pine shoot moth and the European pinesawfly. A method has been developed to permit visual observation of the freezing process of more than one specimen at a time. A freezing chamber consisting of a hole one inch in depth and one-half inch in diameter is located in the upper end of an aluminum rod partially submerged in a dry ice-alcohol mixture. A small filter paper disc, used as the insect platform, rests upon a #40 copper-constantan thermocouple located near the base of the freezing chamber. The thermocouple enters the chamber through a hole in the wall after several circuits around the circumference of the rod to prevent temperature anomalies attributable to thermal conduction within the wire. The thermocouple is connected to a sensitive recording potentiometer. The wall of the freezing chamber is blackened to prevent reflection of light from obscuring the view of the freezing process, through a binocular microscope mounted above the freezing chamber. The moment of freezing is readily recorded on the temperature trace provided by the potentiometer. At a cooling rate of approximately 5°F. per minute, a correction factor of 2.5°F. must be added to the indicated freezing point to obtain the actual temperature at the surface of the platform. When this correction is applied, the results provide data applicable to statistical analysis of freezing point determinations.

scholarly journals Generalized enthalpy model of a high-pressure shift freezing process

2012 ◽  
Vol 468 (2145) ◽  
pp. 2744-2766 ◽  
Author(s):  
Nadia A. S. Smith ◽  
Stephen S. L. Peppin ◽  
Ángel M. Ramos
Keyword(s):  
High Pressure ◽  
Stokes Equations ◽  
Freezing Point ◽  
Food Samples ◽  
Navier Stokes ◽  
Freezing Process ◽  
Frozen Foods ◽  
Navier Stokes Equations ◽  
Pressure Shift ◽  
Pressure Shift Freezing

High-pressure freezing processes are a novel emerging technology in food processing, offering significant improvements to the quality of frozen foods. To be able to simulate plateau times and thermal history under different conditions, in this work, we present a generalized enthalpy model of the high-pressure shift freezing process. The model includes the effects of pressure on conservation of enthalpy and incorporates the freezing point depression of non-dilute food samples. In addition, the significant heat-transfer effects of convection in the pressurizing medium are accounted for by solving the two-dimensional Navier–Stokes equations. We run the model for several numerical tests where the food sample is agar gel, and find good agreement with experimental data from the literature.

Freezing point and melting point of barnacle muscle fibers

1983 ◽  
Vol 61 (10) ◽  
pp. 1116-1121
Author(s):  
Jean-Pierre Caillé
Keyword(s):  
Phase Transition ◽  
Melting Point ◽  
Structural Component ◽  
Freezing Point ◽  
Muscle Fibers ◽  
Experimental Models ◽  
Freezing Process ◽  
Melting Points ◽  
Intact Muscle ◽  
Barnacle Muscle Fibers

The freezing point and the melting point of myoplasm were measured with two experimental models. In all samples, a supercooled stage was reached by lowering the temperature of the sample to approximately −7 °C, and the freezing of the sample was mechanically induced. The freezing process was associated with a phase transition in the interstices between the contractile filaments. In intact muscle fibers, the freezing point showed a structural component (0.43 °C), and the melting point indicated that the intracellular and the extracellular compartments are isotonic. When the sample of myoplasm, previously inserted in a cylindrical cavity was incubated in an electrolyte solution, the freezing point showed a structural component similar to that of the intact muscle fiber, but the melting point was lower than the freezing and the melting points of the embedding solution. This was interpreted as evidence that the counterions around the contractile filaments occupied a nonnegligible fraction of the intracellular compartment.

scholarly journals Efflux of Red Cell Water into Buffered Hypertonic Solutions

1960 ◽  
Vol 43 (4) ◽  
pp. 707-712 ◽  
Author(s):  
Edwin G. Olmstead
Keyword(s):  
Freezing Point ◽  
Maximum Amount ◽  
Red Cells ◽  
Rabbit Serum ◽  
Hypertonic Solution ◽  
Red Cell ◽  
Supernatant Fluid ◽  
Freezing Point Depression ◽  
Cell Water ◽  
Hypertonic Solutions

Buffered NaCl solutions hypertonic to rabbit serum were prepared and freezing point depressions of each determined after dilution with measured amounts of water. Freezing point depression of these dilutions was a linear function of the amount of water added. One ml. of rabbit red cells was added to each 4 ml. of the hypertonic solutions and after incubation at 38°C. for 30 minutes the mixture was centrifuged and a freezing point depression determined on the supernatant fluid. The amount of water added to the hypertonic solutions by the red cells was calcuated from this freezing point depression. For each decrease in the freezing point of -0.093°C. of the surrounding solution red cells gave up approximately 5 ml. of water per 100 ml. of red cells in the range of -0.560 to -0.930°C. Beyond -0.930°C. the amount of water given up by 100 ml. of red cells fits best a parabolic equation. The maximum of this equation occurred at a freezing point of the hypertonic solution of -2.001°C. at which time the maximum amount of water leaving the red cells would be 39.9 ml. per 100 ml. of red cells. The data suggest that only about 43 per cent of the red cell water is available for exchange into solutions of increasing tonicity.

scholarly journals Enhancing the Lubricity of Gas-to-Liquid (GTL) Paraffinic Kerosene: Impact of the Additives on the Physicochemical Properties

2020 ◽  
Author(s):  
Hani Ababnah ◽  
Nasr Mohamed ◽  
Hanif Choudhury ◽  
Lei Lei Zhang ◽  
Rafiqul Gani ◽  
...  
Keyword(s):  
Linoleic Acid ◽  
Physicochemical Properties ◽  
Negative Impact ◽  
Freezing Point ◽  
Ethyl Oleate ◽  
Heat Content ◽  
Wear Scar Diameter ◽  
Dual Nature ◽  
Fuel Jet ◽  
High Concentrations

Abstract Synthetic paraffinic kerosene (SPK) is an ultra-clean fuel with low aromatic content and negligible quantities of sulfur compounds. Although, SPK has a good potential to replace the conventional fuel Jet A-1, it also has some deficiencies. One of them is the low lubricity compared to its conventional counterpart Jet A-1. To improve the lubricity of SPK, three selected additives have been mixed with SPK at different concentrations. The lubricity of the samples was determined experimentally and the samples that meet the industry specifications have been studied further. The effect of the additives on the physicochemical properties, such as, density, flash point, freezing point, viscosity, and heat content, were investigated. Linoleic acid was found to be an excellent lubricity improver even at a very low concentration and its negative impact on the other physicochemical properties was found to be insignificant. Ethyl oleate also demonstrated significant improvement in lubricity at low concentrations but had a negative impact on the fuel’s freezing point at high concentrations. Quinoline, at high concentrations, elevated the blend’s freezing point above the acceptable limits. In parallel to the experimental campaign, a pre-existing mathematical modelling tool was utilized to predict the properties of interest. The lubricity model was successfully introduced into the mathematical model in order to improve the capabilities of the model. Linoleic acid sample showed the best improvement in lubricity of SPK with wear scar diameter of 417 µm; well below the ASTM D7566 maximum limit of 850 µm. The dual nature of this study facilitated the optimization of the physicochemical properties of the fuel samples.

Glycerol and water balance in a near-isosmotic teleost, winter-acclimatized rainbow smelt

1993 ◽  
Vol 71 (9) ◽  
pp. 1849-1854 ◽  
Author(s):  
James A. Raymond
Keyword(s):  
Water Balance ◽  
Freezing Point ◽  
Urine Flow ◽  
Osmerus Mordax ◽  
Rainbow Smelt ◽  
Water Losses ◽  
Drinking Rate ◽  
Osmotic Water ◽  
High Concentrations ◽  
Reduced Drinking

Rainbow smelt, Osmerus mordax, have previously been shown to produce high concentrations of glycerol in winter to avoid freezing, becoming almost isosmotic in a marine environment when temperatures reach the freezing point of seawater. Here it is shown that osmotic water losses, as shown by drinking rate, decrease dramatically in winter as a result of the increased osmolality. Urine flow also appears to decrease in winter in response to reduced drinking. Glycerol is lost through the skin and gills, and probably through intestinal discharge, at total rates ranging from 3.5 to 9.5 mg∙100 g−1∙h−1. Combined permeabilities to glycerol of the gills and skin in the head were in the range 0.9–2.6 × 10−7 cm∙s−1. Glycerol concentrations, efflux, and permeability of the gills were comparable to those for urea in marine elasmobranchs. However, mechanisms for conserving the two osmolytes may differ.

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