425 Matching Results

Search Results

Advanced search parameters have been applied.

in subjects: "Organic Oxygen Compounds"

open access

An experimental/analytical comparison of strains in encapsulated assemblies

A combined experimental and analytical study of strains developed in encapsulated assemblies during casting, curing and thermal excursions is described. The experimental setup, designed to measure in situ strains, consisted of thin, closed-end, Kovar tubes that were instrumented with strain gages and thermocouples before being over-cast with a polymeric encapsulant. Four bisphenol A (three diethanolamine cured and one anhydride cured) epoxy-based materials and one urethane elastomeric material … more

Date: November 1, 1991

Creator: Guess, T.R. & Burchett, S.N.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

The role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii

Research continues on the role of purine degradation in methane biosynthesis and energy production in Methanococcus vannielii. This report summarizes current progress of the research. Topics include: A survey of other methanogens for the purine degradation pathway; isolate and characterize the enzyme and products of formiminoglycine cleavage; ascertain the fate of glycine from the formiminoglycine cleavage; elucidate the route of incorporation of the formyl moiety of formiminoglycine into metha… more

Date: October 22, 1990

Creator: DeMoll, E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Synthesis and chemistry of yttrium and lanthanide metal complexes

The objective of this research project is to determine the special features of complexes of yttrium and the lanthanide metals which will allow the design and synthesis of materials with unique chemical, physical, and catalytic properties. Past studies of yttrium and lanthanide metal alkyl and hydride complexes stabilized by cyclopentadienyl co-ligands have shown that a substantial, often singular, organometallic chemistry is available via these metals. More extensive utilization of the chemical… more

Date: September 1, 1991

Creator: Evans, W. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Morphology of rubber modified epoxy encapsulants

Examination of rubber modified epoxy, cured with diethanol amine, via the transmission electron microscope has shown that a broad distribution of rubber particle sizes exists. The average particle size for particles greater than .1 ..mu..m was found to be .8 ..mu..m. A significant population of particles was found whose diameters are less than .1 ..mu..m. Examination of the particle interface showed that the interface between the dispersed phase and the epoxy matrix was sharp within the accurac… more

Date: January 1, 1979

Creator: Sayre, J.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ultimate Strength, Low Stress Creep Characteristics, and Thermal Intercept Methods for an Epoxy Fiberglass Tension Member Support

A support system utilizing epoxy fiberglass tension members will be used for the UTSI Superconducting Dipole Magnet. Elements of a support system have a basic member which is a link in which a composite is wound around a mandrel. This element uses the strength of the material fibers in a most advantageous way. The flexural and torsional load imputs to the link at its end must be minimized. A spherical bearing with a cylindrical outer surface functions as the central pin. Experience gained in th… more

Date: January 1, 1979

Creator: Niemann, R. C.; Gonczy, J. D.; Hoffman, J. A.; Mataya, K. F.; Smelser, P. & Young, W. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Stress-strain gage measurements on a Nevada Test Site (NTS) event using pairs of triple foil gages

A triple-material stress-strain gage containing foils of ytterbium, manganin, and constantan was tested at LLNL. This gage yields three independent piezoresistance measurements from which an independent set of principal strains and principal stresses can be inferred. We have analyzed the signals from a gage at a specific location buried at a distance from the center of energy of an event at NTS. We inverted the resistivity signals to calculate the stress and strain histories as sensed by the fo… more

Date: November 30, 1990

Creator: Kansa, E. J. & Stout, R. B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Loop-driven graphical unitary group approach to the electron correlation problem, including configuration interaction energy gradients

The Graphical Unitary Group Approach (GUGA) was cast into an extraordinarily powerful form by restructuring the Hamiltonian in terms of loop types. This restructuring allows the adoption of the loop-driven formulation which illuminates vast numbers of previously unappreciated relationships between otherwise distinct Hamiltonian matrix elements. The theoretical/methodological contributions made here include the development of the loop-driven formula generation algorithm, a solution of the upper … more

Date: September 1, 1979

Creator: Brooks, B.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Potential soil contaminant levels of polychlorinated dibenzodioxins and dibenzofurans at industrial facilities employing heat transfer operations

Certain manufacturing facilities formerly used large quantities of polychlorinated biphenyl (PCB) fluids in heat transfer operations. At many of these locations, operations have also involved PCB-containing electrical equipment. Commonly, over many years of plant operations, spills and leaks have resulted in PCB soil contamination. Dioxins and furans have been associated with PCB contamination in both the technical and popular press. Consequently, the need for analyses for dioxins and furans mu… more

Date: April 1, 1992

Creator: Korte, N. E.; Muhr, C. A. & Greene, D. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Operational studies and expected performance of superconducting quadrupole magnets in the first stages of secondary beams

A low current, large bore, epoxy impregnated superconducting quadrupole magnet was constructed at Argonne National Laboratory as a possible prototype for secondary beam use. The quadrupole magnet was placed in the Fermilab P-West High Intensity Area beam for beam quenching tests. Tests were performed by targetting a primary proton beam directly onto the quadrupole coil and by using the quadrupole in its anticipated role as part of the first stage flux collection triplet for a zero degree anti-p… more

Date: August 1, 1983

Creator: Garbincius, P. H.; Mazur, P. O.; Stanek, R. P.; Smith, R. P.; Kim, S. H.; Krieger, C. I. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Chemistry and structure of coal derived asphaltenes and preasphaltenes. Quarterly progress report, October-December 1980. [Methyl-o-xylene; methyl anthracene; methyl naphthalene; methyl pyrene; methyl phenyl ether]

Six model compounds of low molecular weight polymers or oligomers of benzene, o-xylene, anthracene, naphthalene, pyrene, and diphenyl ether were synthesized to study the separate effects of ring number, aliphatic substitution and ether oxygen on pyrolysis yield and microstructure. The results of the experiments on the model compounds were not as expected and hard to explain. The polyphenyl and methyl-o-xylene formed fine and coarse mesophases respectively. Methyl naphthalene and methyl anthrace… more

Date: January 1, 1980

Creator: Yen, T.F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Effects of chemical carcinogens of hemopoiesis, immunopoiesis and viral oncogenesis. Technical progress report, December 1, 1977--September 30, 1978. [Mechanisms of potentiation of viral leukemogenesis by MMS, benzopyrene, and DMBA]

During the past year we have concentrated on defining the circumstances under which methyl methanesulfonate (MMS), benzo(a) pyrene (BP), and 7,12-dimethylbenz(a)anthracene (DMBA) interact with Friend virus (FLV) to produce leukemia. The optimum scheduling for each and also the effective dose levels of the chemicals have been partially determined. There are at least three critical factors which govern whether or not a leukemogenic interaction can be shown between the chemical agents and the viru… more

Date: October 1, 1978

Creator: OKunewick, J.P.; Raikow, R.B. & Meredith, R.F.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Analytical Chemistry Laboratory progress report for FY 1985

The Analytical Chemistry Laboratory is a full-cost-recovery service center, with the primary mission of providing a broad range of technical support services to the scientific and engineering programs at ANL. In addition, ACL conducts a research program in analytical chemistry, works on instrumental and methods development, and provides analytical services for governmental, educational, and industrial organizations. The ACL handles a wide range of analytical problems, from routine standard anal… more

Date: December 1, 1985

Creator: Green, D. W.; Heinrich, R. R. & Jensen, K. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

The Dual Role of Oxygen Functions in Coal Pretreatment and Liquefaction: Crosslinking and Cleavage Reactions

One objective of this program is to prepare polymer models having phenolic, carboxylic, and/or aryl ether groups considered to be important in low rank coals. In order to study the chemistry of these functional groups in a polymeric matrix, it is necessary that the polymer backbone itself should not be subject to cleavage under the reaction conditions. It is expected that poly(phenylene) would fulfill this requirement as a backbone, while providing simple mechanical routes for attaching other f… more

Date: January 1, 1991

Creator: Serio, M. A.; Kroo, E.; Teng, Hsisheng; Charpenay, S. & Solomon, P. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Low Temperature Measurement of Thermal and Mechanical Properties of Phenolic Laminate, the Pultruded Polyester Fiberglass and A and B Epoxy Putty

Low temperature measurements were made and are reported of thermal and mechanical properties of phenolic laminate, pultruded polyester fiberglass, and A and B epoxy putty. To determine the modulus, compressive and tensile stress and strain, an Instron machine, a Tinus-Olsen testing machine, a Wheatstone bridge and strain gages were used. (FS)

Date: January 1, 1979

Creator: Wang, S. T.; Kim, S. H.; Kim, N. S.; Cheng, R. S.; Hoffman, J. & Gonczy, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Radiation carcinogenesis: radioprotectors and photosensitizers

This paper outlines 1) some of the salient features of radiation carcinogenesis that are pertinent to the questions of how the carcinogenic effects might be influenced, 2) the effects of radioprotectors on ionizing radiation-induced cancer, and 3) the effect of photosensitizers on UVR-induced skin cancer.

Date: January 1, 1982

Creator: Fry, R.J.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dimethylether: a low velocity, low diffusion drift chamber gas

There are two main motivations to look for a low electron mobility gas: the first is that a low drift velocity relaxes the need to measure drift times with nanosecond (or even subnanosecond) precision; the second is that (in an ideal drift geometry), the capability of resolving two closely spaced tracks depends upon the ratio of electron mobility to ion mobility ..mu../sub e//..mu../sub i/. Since ..mu../sub i/ is rather constant, the way to separate two tracks is to slow down the electrons. Man… more

Date: January 1, 1983

Creator: Villa, F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effects of radiation at 5 K on organic insulators for superconducting magnets

Recent studies of the effects of irradiation at 5 K on organic insulators for fusion reactors have extended the irradiation dose from 2 x 10/sup 9/ to 1 x 10/sup 10/ rads and have looked for changes due to fast neutrons. For radiation conditions in this experiment the latter had little effect upon electrical and mechanical properties. At a dose of 1 x 10/sup 10/ rads, particle-filled epoxies are at ''end of life'' in terms of mechanical strength, while fiberglass-cloth-filled epoxies retain suf… more

Date: October 1, 1979

Creator: Coltman, R.R. Jr.; Klabunde, C.E.; Kernohan, R.H. & Long, C.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Energy transfer processes in solar energy conversion

The program involves the investigation of excitation transport and electron transfer in complex systems. In the area of electron transfer, we have been studying electron back transfer following donor-acceptor photoinduced electron transfer. We are addressing this problem both theoretically and experimentally. In the area of excitation transport, we have been examining transport in solid solutions, liquid solutions, and in clustered excitation transport systems. Again, we are pursuing both exper… more

Date: January 1, 1988

Creator: Fayer, M.D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Energy transfer processes in solar energy conversion

We have made substantial progress in experimental and theoretical studies in two areas: Photoinduced donor to acceptor electron transfer followed by back transfer in random solutions; and electronic excitation transport in systems with complex inhomogeneous spatial geometries and inhomogeneous energy distributions. Through the development of accurate statistical mechanical theories, we have been able to relate dynamics in complex systems to experimental observables. We have then used the experi… more

Date: November 1, 1989

Creator: Fayer, M.D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Surface-modified bilayer ultrathin membranes

This report briefly describes the preparation, thickness, and absorption spectra of polymer-blend membranes with incorporated semiconductor materials. 2 figs. (JDL)

Date: January 1, 1990

Creator: Yuan, Y.; Cabasso, I. & Fendler, J.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Enzymatic desulfurization of coal

Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes or commercially available enzymes. Our work is focused on the treatment of model'' organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organ… more

Date: December 15, 1988

Creator: Marquis, J.K. (Boston Univ., MA (United States). School of Medicine) & Kitchell, J.P. (Holometrix, Inc., Cambridge, MA (United States))

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

No-migration variance petition for the Waste Isolation Pilot Plant

The Waste Isolation Pilot Plant (WIPP) is a US Department of Energy (DOE) project to provide a research and development facility to demonstrate the safe disposal of radioactive waste resulting from US defense activities and programs. The DOE is developing the WIPP facility as a deep geologic repository in bedded salt for transuranic (TRU) waste currently stored at or generated by DOE defense installations. Approximately 60 percent of the wastes proposed to be emplaced in the WIPP are radioactiv… more

Date: January 1, 1990

Creator: Carnes, R. G.; Hart, J. S. & Knudtsen, K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Irradiation effects on the mechanical properties of composite organic insulators

Four kinds of cloth-filled organic composites (filler: glass or carbon fiber; matrix: epoxy or polymide resin) were irradiated with 2-MeV electrons at room temperature, and were examined with regard to the mechanical properties. Following irradiation, the Young's (tensile) modulus of these composites remains practically unchanged even after irradiation up to 15,000 Mrad. The shear modulus and the ultimate strength, on the other hand, begin to decrease after the absorbed dose reaches about 2000 … more

Date: 1983~

Creator: Egusa, S.; Kirk, M. A.; Birtcher, R. C.; Hagiwara, M. & Kawanishi, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Liquid Phase Methanol Laporte Process Development Unit: Modification, Operation, and Support Studies

The objectives of this program are to implement and test the process improvements identified through the engineering studies of the current program to demonstrate the capability of long-term catalyst activity maintenance, and to perform process and design engineering work that can be applied to a scaled-up Liquid Phase Methanol (LPMEOH) facility. An optional series of PDU runs is offered to extend the testing of the process improvements. A parallel research program will be performed to enhance … more

Date: October 23, 1990

Item Type: Report

Partner: UNT Libraries Government Documents Department