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Advanced NMR approaches in the characterization of coal. Final technical report, September 1, 1990--August 31, 1993

Description: This project addressed two main goals and one much smaller one. The main goals were (1) to improve the significance, reliability and information content in high-resolution NMR (nuclear magnetic resonance) characterization of coal samples and (2) to develop chemically informative NMR imaging techniques for coal. The minor goal was to explore advanced features of dynamic nuclear polarization (DNP) as a technique for coal characterization; this included the development of two DNP probes and the ex… more
Date: September 30, 1993
Creator: Maciel, G. E.
Item Type: Refine your search to only Report
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Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910: Part 1. -- Analyses

Description: From Significance and value of Analyses of Coal: "The analyses published in this report cover samples of coal collected in many different parts of the country with unusual care by experiences men, in such manner as to make them representative of extensive beds of coal."
Date: 1913
Creator: Lord, N. W.
Item Type: Refine your search to only Report
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Capillary discharge extreme ultraviolet lasers. [Colorado State Univ. , Ft. Collins]

Description: The project objective is to explore the generation of soft X-ray laser radiation in a plasma column created by a fast capillary discharge. The proposed capillary lasing scheme offers the potential for compact, simple and efficient soft X-ray laser sources. For this purpose a compact, fast pulse generator which produces 100 kA current pulses with a risetime of 11 ns was constructed. Initial experiments were conducted in evacuated capillaries, in which the plasma is produced by ablation of the ca… more
Date: August 1, 1992
Creator: Rocca, J. J.
Item Type: Refine your search to only Report
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Capillary discharge extreme ultraviolet lasers. Progress report, December 15, 1991--December 14, 1992

Description: The project objective is to explore the generation of soft X-ray laser radiation in a plasma column created by a fast capillary discharge. The proposed capillary lasing scheme offers the potential for compact, simple and efficient soft X-ray laser sources. For this purpose a compact, fast pulse generator which produces 100 kA current pulses with a risetime of 11 ns was constructed. Initial experiments were conducted in evacuated capillaries, in which the plasma is produced by ablation of the ca… more
Date: August 1, 1992
Creator: Rocca, J. J.
Item Type: Refine your search to only Report
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Catalytic applications of mono- and dinuclear complexes containing metal-carbon sigma bonds. Final report, November 1, 1993--October 31, 1996

Description: This report discusses results from several studies involved in the project. Investigations include: vibrational models for surface olefins and alkylidenes; mechanism of the formation and fragmentation of diosmacyclobutanes; reaction of dienes and allenes with diosmacyclobutanes; determination by nematic phase NMR of the structure of mononuclear and dinuclear ethylene complexes of osmium; and generation of ``coordinatively unsaturated`` complexes by protonation of methyl osmium complexes.
Date: December 31, 1996
Creator: Norton, J.R.
Item Type: Refine your search to only Report
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Characterization of Fly Ash From Coal Combustion

Description: Fly ash derived from coal combustion contains predominantly spherical particles which consist of an insoluble aluminosilicate glass containing several mineral impurities. An outer layer, 50 to 300 A thick, is rich in many potentially toxic trace elements in the form of simple and complex sulfates. This layer, which is soluble in water, contains essentially all of the particulate sulfur present in fly ash in the form of sulfate. The actual mechanism(s) of formation of particulate sulfate salts a… more
Date: January 1, 1978
Creator: Natusch, D. F.S.
Item Type: Refine your search to only Article
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Chemically modified electrodes and related solution studies

Description: This report is divided into 5 sections: Ru[sub 4]/Fe complexes of tetra(4[prime]-methyl-2,2[prime]-bipyridine)porphyrin--catalytic epoxidation of olefins; water oxidation catalysis by doubly linked [mu]-oxo ruthenium complexes; polymer films formed by oxidation of transition metal electrodes into solutions of bisbipyridinealkane ligands; polymer films containing [CpMo([mu]-S)][sub 2]S[sub 2]CHR dinuclear clusters;and conducting polymer films for catalyst incorporation.
Date: April 1, 1993
Creator: Elliott, C.M.
Item Type: Refine your search to only Report
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Chemically modified electrodes and related solution studies. Final technical report, January 15, 1991--January 14, 1992

Description: This report is divided into 5 sections: Ru{sub 4}/Fe complexes of tetra(4{prime}-methyl-2,2{prime}-bipyridine)porphyrin--catalytic epoxidation of olefins; water oxidation catalysis by doubly linked {mu}-oxo ruthenium complexes; polymer films formed by oxidation of transition metal electrodes into solutions of bisbipyridinealkane ligands; polymer films containing [CpMo({mu}-S)]{sub 2}S{sub 2}CHR dinuclear clusters;and conducting polymer films for catalyst incorporation.
Date: April 1, 1993
Creator: Elliott, C. M.
Item Type: Refine your search to only Report
open access

Comparative Performance of Two Types of Evacuated Tube Solar Collectors in a Residential Heating and Cooling System - The Progress Report

Description: Two types of evacuated tube solar collectors have been operated in space heating, cooling and domestic hot water heating systems in Colorado State University Solar House I. An experimental collector from Corning Glass Works supplied heat to the system from January 1977 through February 1978, and an experimental collector from Philips Research Laboratory, Aachen, which is currently in use, has been operating since August 1978. A flat absorber plate inside a single-walled glass tube is used in th… more
Date: January 1, 1979
Creator: Conway, T. M.; Duff, W. S.; Loef, G. O. G. & Pratt, R. G.
Item Type: Refine your search to only Article
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Comparison of the Response of a Nai Scintillation Crystal With a Pressurized Ionization Chamber as a Function of Altitude, Radiation Level and RA-226 Concentration

Description: The Grand Junction Uranium Mill Tailings Remedial Action-Radiological Survey Activities Group (UMTRA-RASA) program employs a screening method in which external exposure rates are used to determine if a property contaminated with uranium mill tailings is eligible for remedial action. Portable NaI detectors are used by survey technicians to locate contaminated areas and determine exposure rates. The exposure rate is calculated using a regression equation derived from paired measurements made with… more
Date: January 1, 1986
Creator: Provencher, R.; Smith, G.; Borak, T.B. & Kearney, P.
Item Type: Refine your search to only Article
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Cross-Spectral Study of the Spatial Relationships in the North Pacific Sea-Surface Temperature Anomaly Field. Report No. 23

Description: Cross-spectral analysis is used to examine the dependence of the temporal covariation of sea-surface temperature (SST) anomalies at pairs of spatially separated points in the North Pacific on (1) the time scale of the variations, (2) the relative displacement of the points and (3) their location within the North Pacific basin. Spatial scales considered here range from 1000 kilometers up to the width of the basin. The study focuses on cross-spectral estimates for the interannual frequency band, … more
Date: March 1, 1980
Creator: Middleton, John W.
Item Type: Refine your search to only Report
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Detection of blockages in process piping Los Alamos National Laboratory. Final report

Description: The attached reports and proposal summarize the work to date for the revised Ultrasonic Resonance Interferometry system. The most recent set of experiments, to determine the accuracy of the implementation of a new calibration curve to account for the variation of the wave speed with temperature, were never completed due to lack of funding. The general focus of the ongoing work, outlined in the weekly reports, had been improvements in accuracy of the measurement system using software modificatio… more
Date: October 1, 1994
Creator: Histand, M.B.
Item Type: Refine your search to only Report
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Development of a gas-to-particle conversion model for use in three-dimensional global sulfur budget studies. Final report, 1 August 1991--30 June 1992

Description: A fully-parameterized model for the formation and growth of aerosols via gas-to-particle conversion has been developed and tested. A particularly significant contribution is a new method for the prediction of numbers of particles nucleated using information on the vapor source rate, relative humidity, and preexisting aerosol alone, thus eliminating the need to solve a system of coupled ODEs. Preliminary tests indicate substantial reduction in computational costs, but it is recommended that the … more
Date: August 1, 1993
Creator: Kreidenweis, S. M.
Item Type: Refine your search to only Report
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Development of a kinetic model and calculation of radiation dose estimates for sodium iodide-{sup 131}I in athyroid individuals

Description: The treatment for some thyroid carcinomas involves surgically removing the thyroid gland and administering the radiopharmaceutical Sodium iodide-{sup 131}I (NaI). A diagnostic dose of NaI is given to the patient to determine if remnant tissue from the gland remains or larger doses are administered in order to treat the malignant tissue. Past research regarding NaI uptake and retention in euthyroid individuals (normal functioning thyroid) reveal that radioiodine concentrates mainly in the thyroi… more
Date: July 1, 1997
Creator: Rodriguez, M.
Item Type: Refine your search to only Report
open access

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes

Description: We have obtained a neutron diffraction data set for Os{sub 2}(CO){sub 8}({mu}-C{sub 2}H{sub 4}). While the structure is still being solved, it is already clear that the hybridization at both of the ethylene carbons is sp{sup 3}. Our first interpretation of our liquid crystal NMR results had suggested a very acute H-C-H angle. We have also obtained {sup 13}C liquid crystal data for Os{sub 2}(CO){sub 8}({mu}-C{sub 2}H{sub 4}). Liquid crystal NMR ({sup 13}C as well as {sup 1}H) spectra have been o… more
Date: January 1, 1989
Creator: Norton, J.R.
Item Type: Refine your search to only Report
open access

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes

Description: The report is divided into: vibrational models for surface ethylidenes (on catalyst surfaces); alpha vs beta hydrogen elimination in formation of propene from an osmacyclobutane; mechanism of formation and fragmentation of diosmacyclobutanes; reaction of dienes and allenes with diosmacyclobutanes; structure of Os(CO)[sub 4](C[sub 2]H[sub 4]), an osmacyclopropane; and reaction of [mu]-oxobis [(trifluoromethanesulfanato) (phenyl)iodine(III)] with Group 14 propargyl derivatives and a propargyl eth… more
Date: May 1, 1993
Creator: Norton, J.R.
Item Type: Refine your search to only Report
open access

Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes. Final report

Description: Assignment of the vibrational modes Of Os{sub 2}(CO){sub 8}(CHCH{sub 3}) and Os(CO){sub 4}(C{sub 2}H{sub 4)} has given fingerprint vibrational spectra for the following species when chemisorbed on metal catalyst surfaces: ethylidene and ethylene bound in a metallacyclopropane mode. The formation and fragmentation of diosmacyclobutanes have been shown to involve slippage of the outgoing olefin onto a single osmium, and associative exchange of the olefin from that site. The incorporation of vinyl… more
Date: April 25, 1994
Creator: Norton, J. R.
Item Type: Refine your search to only Report
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Diosmacycloalkanes as models for the formation of hydrocarbons from surface methylenes. Progress report, April 1, 1988--March 31, 1989

Description: We have obtained a neutron diffraction data set for Os{sub 2}(CO){sub 8}({mu}-C{sub 2}H{sub 4}). While the structure is still being solved, it is already clear that the hybridization at both of the ethylene carbons is sp{sup 3}. Our first interpretation of our liquid crystal NMR results had suggested a very acute H-C-H angle. We have also obtained {sup 13}C liquid crystal data for Os{sub 2}(CO){sub 8}({mu}-C{sub 2}H{sub 4}). Liquid crystal NMR ({sup 13}C as well as {sup 1}H) spectra have been o… more
Date: January 1, 1989
Creator: Norton, J. R.
Item Type: Refine your search to only Report
open access

Diosmacycloalkanes as Models for the Formation of Hydrocarbons From Surface Methylenes. Progress Report, November 1, 1991--October 31, 1992

Description: We are making progress on our investigation of the mechanism of olefin exchange with Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8}. We are probing this system by kinetic study of the reaction of Os{sub 2}(C{sub 2}H{sub 4})(CO){sub 8} with butyl acrylate (BA) under various pressures of ethylene.
Date: May 1, 1992
Creator: Norton, J. R.
Item Type: Refine your search to only Report
open access

Diosmacycloalkanes as Models for the Formation of Hydrocarbons From Surface Methylenes. Progress Report, November 1, 1992--October 31, 1993

Description: The report is divided into: vibrational models for surface ethylidenes (on catalyst surfaces); alpha vs beta hydrogen elimination in formation of propene from an osmacyclobutane; mechanism of formation and fragmentation of diosmacyclobutanes; reaction of dienes and allenes with diosmacyclobutanes; structure of Os(CO){sub 4}(C{sub 2}H{sub 4}), an osmacyclopropane; and reaction of {mu}-oxobis [(trifluoromethanesulfanato) (phenyl)iodine(III)] with Group 14 propargyl derivatives and a propargyl eth… more
Date: May 1, 1993
Creator: Norton, J. R.
Item Type: Refine your search to only Report
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