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Research on Saline Water Conversion by Freezing

Description: From Introduction: "Progress of research related to problems encountered in processes for desalination by freezing is summarized in this report, which is the first annual progress report called for under the terms of Grant 14-01-0001-295 made to the Massachusetts Institute of Technology by the Office of Saline Water in 1962."
Date: March 1964
Creator: Sherwood, T. K. & Brian, P. L. T.
Partner: UNT Libraries Government Documents Department

Saline Water Conversion by Freezing: An Integral Processing unit Using a Secondary Refrigerant

Description: From Introduction: "The study of the conversion of saline water by direct freezing using a secondary refrigerant has been sponsored by the the Office of Saline Water at Cornell University since the beginning of 1958. This report first considers the energy relationships which can be the basis for much controversy regarding the freezing process."
Date: August 1960
Creator: Weigandt, H. F.
Partner: UNT Libraries Government Documents Department

A New Process for the Production of Fresh Water From Sea Water

Description: From Summary: "This report is not only the final report under contract #14-01-001-189 but also the first submitted for publication and general distribution on the subject of fresh water from saline water by the Struthers Wells - Scientific Design process."
Date: June 1961
Creator: Svanoe, Hans; Swiger, W. F.; Colton, J. S.; Jewett, J. E. & Margiloff, I. B.
Partner: UNT Libraries Government Documents Department

Statistical Explanation of Spontaneous Freezing of Water Droplets

Description: Note presenting a statistical theory based on the presence of small crystallization nuclei suspended in water developed to explain experimental results showing that, on average, small droplets can be supercooled to lower temperatures than large ones. The average behavior of supercooled droplets is reproduced on the basis of probability theory with an assumed distribution of crystallization nuclei with respect to the temperatures at which the nuclei cause freezing.
Date: December 1950
Creator: Levine, Joseph
Partner: UNT Libraries Government Documents Department

Experimental Investigation of Direct Freeze Separation Process Using Refrigerant R-C318 (Octafluorocyclobutane)

Description: Report concerning the possible use of octafluorocyclobutane, R-C318, being used in the direct freezing process as a means of extracting fresh water from sea water. Topics include using R-C318 to make ice, flash precooling, design of a small direct freezing pilot plant using R-C318, and related economic studies.
Date: April 1967
Creator: Johnson, C. A.; Moore, S. J.; Wagaman, N. D. & Sandell, D. J.
Partner: UNT Libraries Government Documents Department

Analysis of uranium hexafluoride-hydrogen fluoride solutions by freezing point determination : errors caused by liquid -vapor equilibrium

Description: A report detailing the analysis of uranium hexafluoride-hydrogen fluoride solutions by their freezing point determination. This analysis was conducted by measuring vapor pressures at the freezing temperatures of different compositions of uranium hexafluoride-hydrogren fluoride solutions.
Date: 1955
Creator: Davis, W. & Kobisk, E. H.
Partner: UNT Libraries Government Documents Department

Statistical Explanation of Spontaneous Freezing of Water Droplets

Description: Note presenting a theory based on the presence of small crystallization nuclei suspended in water to explain experimental results showing that on the average, small droplets can be supercooled to lower temperatures than large ones. The average behavior of the supercooled droplets is reproduced on the basis of probability theory with an assumed distribution of crystallization nuclei with respect to the temperatures at which the nuclei cause freezing.
Date: December 1950
Creator: Levine, Joseph
Partner: UNT Libraries Government Documents Department

The Paths of Quintessence

Description: The structure of the dark energy equation of state phase plane holds important information on the nature of the physics. We explain the bounds of the freezing and thawing models of scalar field dark energy in terms of the tension between the steepness of the potential vs. the Hubble drag. Additionally, we extend the phase plane structure to modified gravity theories, examine trajectories of models with certain properties, and categorize regions in terms of scalar field hierarchical parameters, showing that dark energy is generically not a slow roll phenomenon.
Date: March 13, 2006
Creator: Linder, Eric V.
Partner: UNT Libraries Government Documents Department

Field Flows of Dark Energy

Description: Scalar field dark energy evolving from a long radiation- or matter-dominated epoch has characteristic dynamics. While slow-roll approximations are invalid, a well defined field expansion captures the key aspects of the dark energy evolution during much of the matter-dominated epoch. Since this behavior is determined, it is not faithfully represented if priors for dynamical quantities are chosen at random. We demonstrate these features for both thawing and freezing fields, and for some modified gravity models, and unify several special cases in the literature.
Date: July 8, 2008
Creator: Cahn, Robert N.; de Putter, Roland & Linder, Eric V.
Partner: UNT Libraries Government Documents Department

Effects of nitrogen tetroxide and water concentration on freezing point and ignition delay of fuming nitric acid

Description: Report presenting an investigation of the interrelated effects of water and nitrogen tetroxide in fuming nitric acid with respect to the freezing points of the acid and ignition delays with several fuels. Results regarding freezing-point experiments, ignition-delay experiments, coincidence of acid compositions giving low freezing points and short ignition delays, and hypotheses on the opposing effects of nitrogen tetroxide and water on ignition delay are provided.
Date: September 24, 1953
Creator: Miller, Riley O.
Partner: UNT Libraries Government Documents Department

Microaspiration for high-pressure freezing: a new method for ultrastructural preservation of fragile and sparse tissues for TEM and electron tomography

Description: High-pressure freezing is the preferred method to prepare thick biological specimens for ultrastructural studies. However, the advantages obtained by this method often prove unattainable for samples that are difficult to handle during the freezing and substitution protocols. Delicate and sparse samples are difficult to manipulate and maintain intact throughout the sequence of freezing, infiltration, embedding, and final orientation for sectioning and subsequent TEM imaging. An established approach to surmount these difficulties is the use of cellulose microdialysis tubing to transport the sample. With an inner diameter of 200 micrometers, the tubing protects small and fragile samples within the thickness constraints of high-pressure freezing, and the tube ends can be sealed to avoid loss of sample. Importantly, the transparency of the tubing allows optical study of the specimen at different steps in the process. Here, we describe the use of a micromanipulator and microinjection apparatus to handle and position delicate specimens within the tubing. We report two biologically significant examples that benefit from this approach, 3D cultures of mammary epithelial cells and cochlear outer hair cells. We illustrate the potential for correlative light and electron microscopy as well as electron tomography.
Date: February 13, 2008
Creator: Auer, Manfred; Triffo, W.J.; Palsdottir, H.; McDonald, K.L.; Inman, J.L.; Bissell, M.J. et al.
Partner: UNT Libraries Government Documents Department

Estimating the Maximum Splat Diameter of a Solidifying Droplet

Description: We present a simple analytical model for the estimation of the maximum splat diameter of an impacting droplet on a subcooled target. This work is an extension of the isothermal model of Pasandideh-Fard et al. (1996). The model uses an energy conservation argument, applied between the initial and final drop configurations, to approximately capture the dynamics of spreading. The effects of viscous dissipation, surface tension, and contact angle are taken into account. Tests against limited experimental data at high Reynolds and Weber numbers indicate that an accuracy of the order of 5% is achieved with no adjustable parameters required. Agreement with experimental data in the limit We {yields} {infinity} is also very good. We additionally propose a simple model for the estimation of the thickness of the freezing layer developed at the droplet-substrate contact during droplet spreading. This model accounts for the effect of thermal contact resistance and its predictions compare favorably with experimental data.
Date: March 31, 1999
Creator: Hadjiconstantinou, N.G.
Partner: UNT Libraries Government Documents Department

The Site B Foundry (Final Report on Part I of P.A. No. 151-ML-54-2, F.S. 41)

Description: The Site B Foundry is equipped for the melting and casting of tuballoy and its alloys. Castings weighing up to 750 pounds and as long as 40 inches can be made. Melting can be carried out in the vacuum, in inert gases or under fluxes. Heating is by high frequency induction. A description of the generally foundry layout, the furnace construction and operation, and of the auxiliary equipment is given in this report. The casting technique used in the Site B Foundry is designed to minimize piping and cold shuts in the billets. The top of the mold is kept hot and freezing of the billet takes place from the bottom. This hot topping minimizes piping. Controlled pouring into warm molds minimized cold shuts.
Date: February 12, 1945
Creator: Lauletta, Paul
Partner: UNT Libraries Government Documents Department

Exploring Metric Symmetry

Description: Relatively minor perturbations to a crystal structure can in some cases result in apparently large changes in symmetry. Changes in space group or even lattice can be induced by heavy metal or halide soaking (Dauter et al, 2001), flash freezing (Skrzypczak-Jankun et al, 1996), and Se-Met substitution (Poulsen et al, 2001). Relations between various space groups and lattices can provide insight in the underlying structural causes for the symmetry or lattice transformations. Furthermore, these relations can be useful in understanding twinning and how to efficiently solve two different but related crystal structures. Although (pseudo) symmetric properties of a certain combination of unit cell parameters and a space group are immediately obvious (such as a pseudo four-fold axis if a is approximately equal to b in an orthorhombic space group), other relations (e.g. Lehtio, et al, 2005) that are less obvious might be crucial to the understanding and detection of certain idiosyncrasies of experimental data. We have developed a set of tools that allows straightforward exploration of possible metric symmetry relations given unit cell parameters and a space group. The new iotbx.explore{_}metric{_}symmetry command produces an overview of the various relations between several possible point groups for a given lattice. Methods for finding relations between a pair of unit cells are also available. The tools described in this newsletter are part of the CCTBX libraries, which are included in the latest (versions July 2006 and up) PHENIX and CCI Apps distributions.
Date: July 31, 2006
Creator: Zwart, P. H.; Grosse-Kunstleve, R. W. & Adams, P. D.
Partner: UNT Libraries Government Documents Department

Zone Freezing Study for Pyrochemical Process Waste Minimization

Description: Pyroprocessing technology is a non-aqueous separation process for treatment of used nuclear fuel. At the heart of pyroprocessing lies the electrorefiner, which electrochemically dissolves uranium from the used fuel at the anode and deposits it onto a cathode. During this operation, sodium, transuranics, and fission product chlorides accumulate in the electrolyte salt (LiCl-KCl). These contaminates change the characteristics of the salt overtime and as a result, large volumes of contaminated salt are being removed, reprocessed and stored as radioactive waste. To reduce the storage volumes and improve recycling process for cost minimization, a salt purification method called zone freezing has been proposed at Korea Atomic Energy Research Institute (KAERI). Zone freezing is melt crystallization process similar to the vertical Bridgeman method. In this process, the eutectic salt is slowly cooled axially from top to bottom. As solidification occurs, the fission products are rejected from the solid interface and forced into the liquid phase. The resulting product is a grown crystal with the bulk of the fission products near the bottom of the salt ingot, where they can be easily be sectioned and removed. Despite successful feasibility report from KAERI on this process, there were many unexplored parameters to help understanding and improving its operational routines. Thus, this becomes the main motivation of this proposed study. The majority of this work has been focused on the CsCl-LiCl-KCl ternary salt. CeCl3-LiCl-KCl was also investigated to check whether or not this process is feasible for the trivalent species—surrogate for rare-earths and transuranics. For the main part of the work, several parameters were varied, they are: (1) the retort advancement rate—1.8, 3.2, and 5.0 mm/hr, (2) the crucible lid configurations—lid versus no-lid, (3) the amount or size of mixture—50 and 400 g, (4) the composition of CsCl in the salt—1, 3, and 5 wt%, ...
Date: May 1, 2012
Creator: Williams, Ammon
Partner: UNT Libraries Government Documents Department

Simulating mixed-phase Arctic stratus clouds: Sensitivity to ice initiationmechanisms

Description: The importance of Arctic mixed-phase clouds on radiation and the Arctic climate is well known. However, the development of mixed-phase cloud parameterization for use in large scale models is limited by lack of both related observations and numerical studies using multidimensional models with advanced microphysics that provide the basis for understanding the relative importance of different microphysical processes that take place in mixed-phase clouds. To improve the representation of mixed-phase cloud processes in the GISS GCM we use the GISS single-column model coupled to a bin resolved microphysics (BRM) scheme that was specially designed to simulate mixed-phase clouds and aerosol-cloud interactions. Using this model with the microphysical measurements obtained from the DOE ARM Mixed-Phase Arctic Cloud Experiment (MPACE) campaign in October 2004 at the North Slope of Alaska, we investigate the effect of ice initiation processes and Bergeron-Findeisen process (BFP) on glaciation time and longevity of single-layer stratiform mixed-phase clouds. We focus on observations taken during October 9th-10th, which indicated the presence of a single-layer mixed-phase clouds. We performed several sets of 12-hour simulations to examine model sensitivity to different ice initiation mechanisms and evaluate model output (hydrometeors concentrations, contents, effective radii, precipitation fluxes, and radar reflectivity) against measurements from the MPACE Intensive Observing Period. Overall, the model qualitatively simulates ice crystal concentration and hydrometeors content, but it fails to predict quantitatively the effective radii of ice particles and their vertical profiles. In particular, the ice effective radii are overestimated by at least 50%. However, using the same definition as used for observations, the effective radii simulated and that observed were more comparable. We find that for the single-layer stratiform mixed-phase clouds simulated, process of ice phase initiation due to freezing of supercooled water in both saturated and subsaturated (w.r.t. water) environments is as important as primary ice crystal origination ...
Date: April 10, 2009
Creator: Sednev, I.; Menon, S. & McFarquhar, G.
Partner: UNT Libraries Government Documents Department

Methane de-NOX for Utility PC Boilers

Description: Large-scale combustion tests with caking bituminous coal was on hold this quarter mainly due to Riley's Commercial Burner Test Facility (CBTF) not having adequate weatherproofing to support operation under freezing conditions. The CBTF was secured and decommissioned for the winter season. CBTF bituminous coal tests shall continue to remain on hold now as a result of project funding limitations, however. No further modifications at the CBTF are planned until needed support is obtained. Activities this quarter have concentrated on finding additional support for the project. Currently, GTI has been granted a no-cost time extension through September 2005 and efforts to secure more support will continue in hopes that large-scale preheat caking bituminous combustion tests will be carried out as planned.
Date: March 31, 2005
Creator: Bryan, Bruce; Rabovitser, Joseph; Nester, Serguei & Wohadlo, Stan
Partner: UNT Libraries Government Documents Department

Investigation of cryopreservation methods for adherent nerve cell networks in vitro.

Description: Cryopreservation in suspension is commonplace for a variety of cell types. However, cryopreservation of adherent cells has achieved limited success. This research aimed to cryopreserve adherent nerve cell networks in vitro in a manner that preserved network morphology and physiology. Successful implementation would enable long term storage of adherent neuronal networks on microelectrode arrays and on-demand access for use in pharmacological and toxicological testing. Based upon morphological assessments, excellent post-thaw preservation was obtained and post-thaw cultures survived in a transitional medium for up to 3.5 hours. However, transitions to native culture medium post-thaw presented difficulties, ultimately resulting in necrosis. A discussion of methods to supplement the current research and increase post-thaw viability is included in the thesis.
Date: December 2009
Creator: Webb, Veronica Fine
Partner: UNT Libraries