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Irreversible Adsorption of Phenolic Compounds by Activated Carbons

Description: Studies were undertaken to determine the reasons why phenolic sorbates can be difficult to remove and recover from activated carbons. The chemical properties of the sorbate and the adsorbent surface, and the influences of changes in the adsorption and desorption conditions were investigated. Comparison of isotherms established after different contact times or at different temperatures indicated that phenolic compounds react on carbon surfaces. The reaction rate is a strong function of temperature. Regeneration of carbons by leaching with acetone recovered at least as much phenol as did regeneration with other solvents or with displacers. The physiochemical properties of adsorbents influences irreversible uptakes. Sorbates differed markedly in their tendencies to undergo irreversible adsorption. 64 refs., 47 figs., 32 tabs.
Date: December 1988
Creator: Grant, T. M. & King, C. J.
Partner: UNT Libraries Government Documents Department

Development and application of resistive pulse spectroscopy: studies on the size, form and deformability of red blood cells

Description: The following studies were conducted using the resistive pulse spectroscopy (RPS) technique: cumulative spectra and individual pulse forms for rigid latex polymer spheres; acquisition and analysis of RPS spectral data by means of special computer program; interaction of red blood cells with glutaraldehyde; membrane properties of erythrocytes undergoing abrupt osmotic hemolysis; reversible effects of the binding of chlorpromazine HCl at the red cell membrane surface; effects of high cholesterol diet on erythrocytes of guinea pigs; and multi-population analysis for a mixture of fetal and maternal red cells. (HLW)
Date: January 1979
Creator: Yee, J. P.
Partner: UNT Libraries Government Documents Department

Hydrogen-related effects in crystalline semiconductors

Description: Recent experimental and theoretical information regarding the states of hydrogen in crystalline semiconductors is reviewed. The abundance of results illustrates that hydrogen does not preferentially occupy a few specific lattice sites but that it binds to native defects and impurities, forming a large variety of neutral and electrically active complexes. The study of hydrogen passivated shallow acceptors and donors and of partially passivated multivalent acceptors has yielded information on the electronic and real space structure and on the chemical composition of these complexes. Infrared spectroscopy, ion channeling, hydrogen isotope substitution and electric field drift experiments have shown that both static trigonal complexes as well as centers with tunneling hydrogen exist. Total energy calculations indicate that the charge state of the hydrogen ion which leads to passivation dominates, i.e., H/sup +/ in p-type and H/sup /minus// in n-type crystals. Recent theoretical calculations indicate that is unlikely for a large fraction of the atomic hydrogen to exist in its neutral state, a result which is consistent with the total absence of any Electron Paramagnetic Resonance (EPR) signal. An alternative explanation for this result is the formation of H/sub 2/. Despite the numerous experimental and theoretical results on hydrogen-related effects in Ge and Si there remains a wealth of interesting physics to be explored, especially in compound and alloy semiconductors. 6 refs., 6 figs.
Date: August 1, 1988
Creator: Haller, E. E.
Partner: UNT Libraries Government Documents Department

Bevalac operations update

Description: The Bevalac passed the recent Tiger Team assessment with flying colors, thanks to the unremitting effort of countless people over the last several months, pulling miles of cables, sending tons of valuable'' junk to salvage, painting, pushing brooms, writing operating procedures. It is time to look ahead now and plan for doing science again; however, it is not business as usual. The Bevalac survived, but not without changes. There are more procedures to be followed, safety appraisals to be made, training to be gone through. The primary goal is not just to get a task done, but to get it done in a safe manner according to code. If this means a delay in a run because enough time wasn't allotted for making a change in the setup, then the experiment will be delayed. Many of the obvious changes you will find the next time you come to work here are summarized in this newsletter. We will inform you of others as they are forthcoming. Also we will discuss these changes at our We Survived the Tigers, but{hor ellipsis}'' Users' Information Meeting at the Washington APS meeting. Details are inside this report.
Date: February 1, 1991
Partner: UNT Libraries Government Documents Department

Putting synchrotron radiation to work: New opportunities for industrial R D

Description: This paper describes the basic categories of experimental techniques that have been successfully exploited at existing synchrotron facilities or, in some cases, that are expected to join the research armamentarium at the next-generation synchrotron sources now under construction, such as the ALS. In each case, a selection of typical industrial applications is noted.
Date: March 1, 1991
Partner: UNT Libraries Government Documents Department

Second invitational well-testing symposium proceedings

Description: The symposium dealt with the state of the art of injection of fluids underground, and its application to geothermal systems in particular. Separate abstracts were prepared for fourteen papers and three abstracts of papers were listed by title. Three papers were previously abstracted for EDB.
Date: January 1, 1978
Partner: UNT Libraries Government Documents Department

Windows and lighting program

Description: More than 30% of all energy use in buildings is attributable to two sources: windows and lighting. Together they account for annual consumer energy expenditures of more than $50 billion. Each affects not only energy use by other major building systems, but also comfort and productivity -- factors that influence building economics far more than does direct energy consumption alone. Windows play a unique role in the building envelope, physically separating the conditioned space from the world outside without sacrificing vital visual contact. Throughout the indoor environment, lighting systems facilitate a variety of tasks associated with a wide range of visual requirements while defining the luminous qualities of the indoor environment. Windows and lighting are thus essential components of any comprehensive building science program. Despite important achievements in reducing building energy consumption over the past decade, significant additional savings are still possible. These will come from two complementary strategies: (1) improve building designs so that they effectively apply existing technologies and extend the market penetration of these technologies; and (2) develop advanced technologies that increase the savings potential of each application. Both the Windows and Daylighting Group and the Lighting System Research Group have made substantial contributions in each of these areas, and continue to do so through the ongoing research summarized here. 23 refs., 16 figs.
Date: June 1, 1990
Partner: UNT Libraries Government Documents Department

Molybdenum--substrate interactions in nitrogenase: an EXAFS study

Description: The sensitivity of x-ray absorption edge spectra and extended x-ray absorption fine structure (EXAFS) to the environment of metal atoms make x-ray absorption spectroscopy a useful probe of the environment of the molybdenum in nitrogenase. It is of particular interest to investigate any perturbations of the environment of the molybdenum due to the presence of nitrogenase substrates. The results of measurements of the x-ray absorption spectra of nitrogenase samples by the absorption and fluorescence detection techniques are compared. The procedures used for the growth of Azotobacter vinelandii for the production of nitrogenase and the procedures used for the purification of nitrogenase are described in detail.
Date: July 1, 1978
Creator: Smith, J. P.
Partner: UNT Libraries Government Documents Department

Measurement of Circumsolar Radiation. Status Report

Description: The major accomplishments of this project include the design, construction, and deployment of four complete circumsolar telescope systems. The telescopes have been maintained and data have been collected from a total of nine sites over the past two years. The data upon reaching LBL have been compiled, validated and analyzed for dissemination to DOE and other users. LBL has been collaborating with other national laboratories to quantify the impact of circumsolar radiation on specific solar collector designs. Requests for data from a wide variety of solar users have been fulfilled.
Date: September 1978
Creator: Grether, D. F.; Hunt, A.; Evans, D. & Wahlig, M.
Partner: UNT Libraries Government Documents Department