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Corrosion Research Center of the University of Minnesota. Progress report, July 1, 1980-December 31, 1980

Description: At present, the research ranges from the quantum mechanics of the corrosion unit reactions, organic and inorganic coatings, surface reactions on polymers, metals and semiconductors to high-temperature chemistry of interest to solar-energy conversion. A second objective of the Center is to increase the utilization of corrosion data by the technical community through education and through the dissemination of appropriately formatted information. At present, two projects are in the planning stage for the near future. One is a pedagogical symposium on corrosion in microelectronic components and systems; the other is a series of lectures and videotapes, as well as a workshop on cathodic protection.
Date: January 30, 1981
Creator: Oriani, R.A.
Partner: UNT Libraries Government Documents Department

Nuclear-structure studies with pions and heavy ions. Progress report, June 1, 1980-May 31, 1981

Description: Experiments performed at the Los Alamos Meson Physics Facility yielded very striking results. In inelastic pion scattering from /sup 14/C near the (3,3) resonance cross sections ratios R = sigma(..pi../sup +/)/sigma(..pi../sup -/) and R/sup -1/ = sigma(..pi../sup -/)/sigma(..pi../sup +/) were observed that are significantly larger than the free pion-nucleon values. These results were interpreted as due to strong cancellations of the neutron and proton components in the transition amplitude. Measurements of /sup 13/C(..pi..,..pi..') excitation functions between 100 and 300 MeV at two momentum transfers showed dramatically different energy dependencies for ..delta..S =0 and ..delta..S = 1 transitions. They were used to derive nuclear structure information on several highly excited states. Pion data for other nuclei (/sup 12/C, /sup 16/O, /sup 40/Ca, etc.) were analyzed and information on isospin mixing, the double-charge-exchange reaction mechanism, and the excitation of collective states was extracted. Further data were taken with a 547 MeV proton beam on /sup 13/C. The data taking for the (t,t') and (/sup 3/He,/sup 3/He') reactions at the Los Alamos Van de Graaff has been completed. The continuing studies of the heavy-ion nucleus optical potential yielded information on very systematic dependencies of the potential depths on the incident energy.
Date: March 1, 1981
Creator: Dehnhard, D.
Partner: UNT Libraries Government Documents Department

Photo-induced cataphoretic isotope separation. Final report, June 15, 1976-June 15, 1981

Description: The original studies were undertaken to study the feasibility of radiation-induced cataphoretic separation. This part of the work is concerned with laser-induced cataphoretic separation in neon using a He-Ne 6328A laser. The basic concept of radiation-induced caphoretic isotope separation is based on the preferential excitation of one isotope with the result that one isotope is more readily ionized, and relatively more of its ions move toward the cathode in the dc discharge. For the later part of the work a second radiation source was added, a helical Ne/sup 20/ radiation lamp. Radiation-induced cataphoretic isotope separation has not been observed. Selective excitation has been achieved by both the He-Ne/sup 20/ 6328A laser and the Ne/sup 20/ helical radiation lamp in spite of the fact that the isotope shift is comprable with Doppler-broadened linewidths. Collisional excitation exchange between the Ne/sup 20/ and Ne/sup 22/ atoms does not appear to be a problem for the neon partial pressure range involved. The population of the 3S/sub 2/ and 2p/sub 4/ laser levels (6328A) are apparently too low to offer reasonable expectation of inducing observable cataphoretic isotope separation by means of the 6328A laser radiation, even with the high detection sensitivity of the scanning Fabry-Perot spectrometer sytem. The use of the additional radiation source in the form of a helical Ne/sup 20/ radiation lamp has not improved the effectiveness of the laser 6328A laser. It has become clear from these experiments, however, that for isotope separation in neon it is well to concentrate on using radiation sources that interact mainly with the ls population.
Date: March 1, 1981
Creator: Carruthers, J A
Partner: UNT Libraries Government Documents Department

Rock bed heat accumulators. Final report

Description: The principal objectives of the research program on rock bed heat accumulators (or RBHA) are: (1) to investigate the technical and economic feasibility of storing large amounts of thermal energy (in the tens of MWt range) at high temperature (up to 500/sup 0/C) over extended periods of time (up to 6 months) using native earth or rock materials; (2) to conduct studies to establish the performance characteristics of large rock bed heat accumulators at various power and temperature levels compatible with thermal conversion systems; and (3) to assess the materials and environmental problems associated with the operation of such large heat accumulators. Results of the study indicate that rock bed heat accumulators for seasonal storage are both technically and economically feasible, and hence could be exploited in various applications in which storage plays an essential role such as solar power and total energy systems, district and cogeneration heating systems.
Date: December 1, 1977
Creator: Riaz, M.
Partner: UNT Libraries Government Documents Department

Energy transfer and utilization in biological systems. Final report, September 1, 1967--September 15, 1976. [Fluorescence studies of photosynthesis]

Description: In fluorescence studies of the photosynthetic process it was shown that the photosynthetic rate and light loss via chlorophyll fluorescence are strictly complementary. The exciplex state of matter responsible for most photochemistry was discovered and a wide variety of information about the state gained from studies of indole exciplexes. In addition to the nature of the bonding, degree of stability and general excited state behavior of indole exciplexes, their ability to lose electrons in a highly temperature-dependent quenching process was established. Time resolved emission spectroscopy demonstrated that local-movement relaxation in the interior of globular proteins occurs more rapidly than 10/sup -9/ sec. Subsequent studies show this to be an important and general time cut-off in the conformational fluctuations which support protein function. Although a chlorophyll-chlorophyll exciplex was produced, its relevance to the System II trapping center was not established. Only recently has the exciplex nature of both System I and System II trapping centers been exposed by others.
Date: March 1, 1978
Creator: Lumry, R.W.
Partner: UNT Libraries Government Documents Department

Contribution of electronically excited states to the radiation chemistry of organic systems. Progress report, September 1, 1976--August 31, 1977

Description: The fluorescence of N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD) has been studied in the solvents n-hexane, methylcyclohexane, cyclohexane, isooctane, and tetramethylsilane for excitation energies below and above the photoionization threshold. Evidence is obtained for the existence, as a major intermediate in the photoionization process of a coherent but spatially diffuse excited state of TMPD. Electron impact spectra of NH/sub 3/ at low energies and 90/sup 0/ scattering angle has failed to reveal any evidence for a low-lying valence triplet. For simple saturated hydrocarbons, large angle electron-impact spectra also fail to reveal any evidence for low-lying valence triplet states. Therefore if valence-shell transitions exist at all in these molecules they must be imbedded at significantly higher energies in the absorption manifold. The fluorescence of the A ..-->.. X transition in ammonia-d/sub 3/ has been studied in the presence of saturated hydrocarbon perturbers up to densities of approximately 6 M. Essentially no change in fluorescence quantum yield is observed. This eliminates inelastic processes as contributing importantly to pressure broadening and to shifting of the A reverse arrow X transition. The pressure broadening and pressure shifting of the first 10 vibrational peaks in the A reverse arrow X (n/sub N/ ..-->.. 3s Rydberg) absorption of NH/sub 3/ has been studied using He, Ne, Ar, N/sub 2/, CH/sub 4/, CF/sub 4/ and SF/sub 6/ gases up to pressures of approximately 100 atm. Both blue and red shifts are observed depending on the nature of the perturber. A dependence of the magnitude of the shift on vibrational level is observed and attributed to important variations of the electronic wavefunction of the upper state with position of the nuclei.
Date: January 1, 1977
Creator: Lipsky, S.
Partner: UNT Libraries Government Documents Department

Grid-connected integrated community energy system. Phase II, Stage 2, final report. Preliminary design pyrolysis facility. [Andco-Torrax system]

Description: The University of Minnesota is studying and planning a grid connected integrated community energy system to include disposal of wastes from health centers and utilizing the heat generated. The University of Minnesota has purchased the so called Southeast Generating Station from the Northern States Power Company. This plant contains two coal-fired boilers that will be retrofitted to burn low-sulfur Montana coal. Building modifications and additions will be made to support the components of the Andco-Torrax system and integrate the system with the rest of the plant. The Andco-Torrax system is a new high-temperature refuse-conversion process known technically as slagging pyrolysis. Although the pyrolysis of solid waste is a relatively new innovation, pyrolysis processes have been used for years by industry. This report covers the preliminary design and operation of the system. (MCW)
Date: March 22, 1978
Partner: UNT Libraries Government Documents Department

Grid-connected integrated community energy system. Phase II, Stage 2, final report. Executive summary

Description: The University of Minnesota Grid-ICES was divided into four identifiable programs in order to study the feasibility of each of the parts of the ICES independently. The total program involves cogeneration, fuel conversion, fuel substitution, and energy conservation by system change. This Phase II report substantiates the theory that the Basic Grid ICES is not only energy-effective, but it will become cost effective as unit operating costs adjust to supply and demand in the 1980's. The Basic Program involves the cogeneration of steam and electricity. The University of Minnesota has been following an orderly process of converting its Central Heating Plant from gas-oil to 100% coal since 1973. The first step in the transition is complete. The University is presently 100% on coal, and will begin the second step, the test burning of low Btu Western coal during the spring, summer, and fall, and high Btu Eastern coal during the high thermal winter period. The final step to 100% Western coal is planned to be completed by 1980. In conjunction with the final step a retired Northern States Power generating plant has been purchased and is in the process of being retrofitted for topping the existing plant steam output during the winter months. The Basic Plan of ICES involves the add-on work and expense of installing additional boiler capacity at Southeast Steam and non-condensing electric generating capability. This will permit the simultaneous generation of electricity and heat dependent upon the thermal requirements of the heating and cooling system in University buildings. This volume presents an overview of the Community and the ICES. (MCW)
Date: March 22, 1978
Partner: UNT Libraries Government Documents Department

Grid-connected integrated community energy system. Phase II, Stage 1, final report. Conceptual design: pyrolysis and waste management systems

Description: The University of Minnesota is studying and planning a grid-connected integrated community energy system to include disposal of wastes from health centers and utilizing the heat generated. Following initial definition of the 7-county metropolitan region for which the solid waste management system is to be planned, information is then necessary about the nature of the waste generated within this region. Estimates of the quantities generated, generation rates, and properties of the waste to be collected and disposed of are required in order to determine the appropriate size and capacity of the system. These estimates are designated and subsequently referred to as ''system input''. Institutional information is also necessary in designing the planned system, to be compatible with existing institutional operations and procedures, or to offer a minimum amount of problems to the participating institution in the region. Initial considerations of health care institutions generating solid waste within the defined region are made on a comprehensive basis without any attempt to select out or include feasible candidate institutions, or institutional categories. As the study progresses, various criteria are used in selecting potential candidate institutional categories and institutions within the 7-county region as offering the most feasible solid waste system input to be successfully developed into a centralized program; however, it is hoped that such a system if developed could be maintained for the entire 7-county region, and remain comprehensive to the entire health care industry. (MCW)
Date: March 8, 1978
Partner: UNT Libraries Government Documents Department

Grid connected integrated community energy system. Phase II: final stage 2 report. Outline specifications of cogeneration plant; continued

Description: Specifications are presented for the electrical equipment, site preparation, building construction and mechanical systems for a dual-purpose power plant to be located on the University of Minnesota campus. This power plant will supply steam and electrical power to a grid-connected Integrated Community Energy System. (LCL)
Date: March 22, 1978
Partner: UNT Libraries Government Documents Department

Grid-connected integrated community energy system. Phase II, Stage 1, final report. Conceptual design, demand and fuel projections and cost analysis

Description: The Phase I Report, Grid ICES, presented the broad alternatives and implications for development of an energy system satisfying thermal demand with the co-generation of electric power, all predicated on the use of solid fuels. Participants of the system are the University of Minnesota, operator and primary thermal user, and Northern States Power Company, primary electrical user; with St. Mary's Hospital, Fairview Hospital, and Augsburg College as Add-on Customers for the thermal service (Option I). Included for consideration are the Options of (II) solid waste disposal by the Pyrolysis Method, with heat recovery, and (III) conversion of a portion of the thermal system from steam to hot water distribution to increase co-generation capability and as a demonstration system for future expansion. This report presents the conceptual design of the energy system and each Option, with the economic implications identified so that selection of the final system can be made. Draft outline of the Environmental Assessment for the project is submitted as a separate report.
Date: March 8, 1978
Partner: UNT Libraries Government Documents Department

University of Minnesota progress report No. 4215

Description: Medium-energy nuclear physics research at the University of Minnesota is reviewed. The following studies were undertaken: HRS development; /sup 58/ /sup 60/ /sup 62/ /sup 64/Ni(p,p') at 800 MeV; proton scattering on 2s-1d-shell nuclei; search for orbit flip states in /sup 90/Zr, /sup 120/Sn, /sup 144/Sm, and /sup 208/Pb; large-angle A/sup 116/ /sup 124/Sn, /sup 208/Pb elastic scattering; proton scattering from heavy deformed nuclei; unnatural-parity states in /sup 6/Li, /sup 10/B, /sup 12/C, /sup 14/N, and /sup 28/Si; microscopic form factor calculations - force studies; DEC PDP 11/60 computer; theoretical analysis computer programs; inelastic electron scattering on /sup 90/Zr; and EPICS programs. Three of the above topics, with significant amounts of data, are indexed separately. 40 figures, 1 table. (RWR)
Date: January 1, 1979
Creator: Hintz, N.M.
Partner: UNT Libraries Government Documents Department

Reactions of ions with atomic and molecular free radicals. Progress report, May 1, 1978--April 30, 1979. [Summaries of research activities at Univ. of Minnesota]

Description: A program of research was undertaken to study the dynamics of the reactions of ions with atomic and molecular free radicals, using a merged molecular beam technique. The objectives of this research are to obtain fundamental information on reaction mechanisms in reactions of species having open-shell electronic configurations, and to investigate the importance of electronic nonadiabaticity in chemical reactions. During the present contract year work was done on completing studies of the reaction D/sub 2//sup +/ + F(/sup 2/P) ..-->.. FD/sup +/ + D and of the complementary reactions D/sub 2//sup +/ + HF ..-->.. FD/sub 2//sup 2/ + H, D/sub 2//sup +/ + HF ..-->.. FHD/sup +/ + D, and D/sub 2//sup +/ + HF ..-->.. FD/sup +/ + HD. Also some experiments were carried out on the reaction C/sup +/ + D/sub 2/ ..-->.. CD/sup +/ + D to complement our previous work on the opposite initial charge state of the system, D/sub 2//sup +/ + C ..-->.. CD/sup +/ + D. Finally, as an aid in interpreting our merged-beam data at kinetic energies as low as 0.002 eV. A theoretical analysis was performed of the differential cross sections for ion-dipole capture collisions followed by direct-mode reactions. The results indicate that shifts in the product angular distribution with a change in the reactant kinetic energy do not necessarily imply a change in the short-range reaction mechanism. A list of publications is included.
Date: January 1, 1979
Creator: Gentry, W.R.
Partner: UNT Libraries Government Documents Department

Reactions of ions with atomic and molecular free radicals. Progress report, May 1, 1981-April 30, 1982. [Summaries of research activities at the University of Minnesota]

Description: Analysis and interpretation of the data on the reactions of H/sub 2//sup +/ with N, C, O and F were completed, along with some supplementary investigations of collision-induced dissociation of the exotic species NH/sub 3//sup 2 +/ and CS/sub 2//sup 3 +/. As the focus of this project shifts to other systems and phenomena, construction of a new crossed, pulsed molecular beam apparatus has been begun, and is now about 75% complete. The new instrument will permit state-resolved studies of energy transfer and reactive processes to be carried out with unprecendented sensitivity.
Date: November 1, 1981
Creator: Gentry, W.R.
Partner: UNT Libraries Government Documents Department

Reactions of ions with atomic and molecular free radicals. Progress report, May 1, 1979-April 30, 1980

Description: A very detailed study of the microscopic dynamics of the reaction D/sub 2//sup +/ + F(/sup 2/p) ..-->.. FD/sup +/ + D, over the range of relative kinetic energy from 0.001 eV to 25 eV is reported. At very low collision energy, the total reaction cross section is governed by long-range forces - principally the charge-quadrupole interaction, which favors reactions on PI-type potential energy surfaces in the covalent interaction region. At high collision energies, a clear transition to reactions on a strongly repulsive potential energy surface is observed. The change in reaction dynamics is evident from the shape of the energy dependence of the total reaction cross section, and from a shift in the product angular distribution from 0/sup 0/ toward 180/sup 0/ in the center-of-mass coordinate system.
Date: January 1, 1980
Creator: Gentry, W.R.
Partner: UNT Libraries Government Documents Department

Photo-induced cataphoretic isotope separation. Progress report, June 15, 1978--June 15, 1979

Description: The studies on radiation-induced cataphoretic isotope separation has been associated with the use of a 0.63-..mu.. He:Ne laser as the radiation source in an attempt to obtain separation of /sup 20/Ne and /sup 22/Ne isotopes. A cataphoretic discharge tube containing mixed neon isotopes is within the laser resonator, whereas the laser tube contains only one neon isotope. Cataphoretic separation of the neon isotopes has not been observed, although selective excitation of one isotope has been demonstrated and a very sensitive technique for detecting cataphoretic isotope separation has been developed. Also, it is found that the exchange rate between the two neon isotopes in the excited laser levels is not great enough to significantly reduce the effect of selective excitation. Measurements of the current changes induced by the radiation indicate that the populations of those levels with which the laser radiation interacts is too small.
Date: June 1, 1979
Creator: Carruthers, J.A.
Partner: UNT Libraries Government Documents Department

Experimental formation of chalk from calcareous ooze. Technical progress report

Description: Samples of calcareous ooze collected from the tropical and equatorial Atlantic Ocean were subjected to hydrothermal alteration in order to simulate the diagenesis of chalk. Changes in mineralogy and morphology of enclosed microfossils were measured. (ACR)
Date: February 15, 1981
Creator: Seyfried, W.E. & Johnson, T.C.
Partner: UNT Libraries Government Documents Department

Vertebrate behavior and ecology. Progress report, July 1, 1977-May 31, 1980

Description: Engineering design and development concentrated on five aspects during the past year: (1) development of high power output transmitters for monitoring animals from greater distances; (2) improvement and updating of a sonic transmitting and receiving system for monitoring fish and marine mammals; (3) design and testing of corrosive links which permit a transmitter to release from an animal at a specified time; (4) development of high frequency transmitters; and (5) development and testing of time delay transmitters. Field efforts resulted in further information on activity patterns and movements of sea otters in California and Alaska and of walleye pike in experimental channels. Three manuscripts and two theses presented as part of this report describe these aspects in detail.
Date: June 1, 1980
Creator: Tester, J R & Siniff, D B
Partner: UNT Libraries Government Documents Department

Vertebrate behavior and ecology. Progress report, 1 July 1978--30 June 1979

Description: Efforts in engineering design and development this year emphasized improvement in the quality and versatility of radio transmitters, use of microprocessors in an automated fish tracking system, and construction of an automated system to monitor movements and activities of aquatic mammals in response to water temperature. Improved radio transmitters were used on a variety of species including sea otters, manatees, and wall-eyed pike. The fish tracking system, installed at Monticello, Minnesota, will next be modified for monitoring marine mammal movements. The temperature data logging system was tested on manatees in the St. John River near Blue Springs, Florida. The long-term goal in the subproject on evaluation of census methods is to utilize the extensive experience, technology, and equipment developed over the years in radio telemetry to resolve basic problems in animal census and population study methods. During the past year, efforts have resulted in information on activity patterns and the behavioral repertoire of sea otters and on the response of otters to contamination by Alaskan crude oil. Three preliminary manuscripts presented as part of this report describe these aspects in detail.
Date: July 1, 1979
Creator: Tester, J.R. & Siniff, D.B.
Partner: UNT Libraries Government Documents Department