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Response of Shortgrass Plains Vegetation to Chronic and Seasonally Administered Gamma Radiation

Description: In order to determine the effect of radiation on the structure of native shortgrass plains vegetation, an 8750 Ci 137Cs source was installed on the Central Plains Experimental Range near Nunn, Colorado; The experimental area was divided into 6 treatment sectors, a control, 2 sectors for chronic exposure (irradiation initiated April 1969 and continuing as of August 1971), and one each for spring, summer and late fall seasonal semi-acute (30 day), exposures which were administered during April, J… more
Date: August 1, 1971
Creator: Fraley, L. Jr.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Geothermal Resource Investigations: Imperial Valley, California. Site location report, deep geothermal test well

Description: Data for use in siting a deep geothermal test well in the East Mesa area of Imperial County, California are summarized. The data relate to a geothermal anomaly known as the Mesa anomaly. It is concluded that the thermal feature forming the Mesa anomaly is a manifestation of a sizable convective hydrothermal system embracing an area of about 19 square miles and a considerable volume of saturated sediment in the Salton trough. The upper surface of the thermal feature between depths of 200 and 1,0… more
Date: October 1, 1971
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Liquid metal bearings technology for large, high-temperature, sodium rotating machinery. Development and test of high-temperature proximity probe for use in liquid sodium. Fourth topical report

Description: An inductance-type, proximity-probe system for measurement of bearing film thicknesses and shaft orbits in high-temperature, liquid-sodium environment has been developed, built and tested. The probe system is designed to operate at temperatures up to 1200/sup 0/F and gap range of 0.004'' to 0.080'', with good linearity over about three-quarters of the range, when using probe pairs connected in push-pull. The probes were tested extensively in both gas and sodium environments, culminating in a 68… more
Date: June 1, 1971
Creator: Hoogenboom, I. & Kissinger, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ABSOLUTE ASYMMETRIC SYNTHESIS. I. ON THE MECHANISM OF THEPHOTOCHEMICAL ABSOLUTE ASYMMETRIC SYNTHESIS OF HELICENES WITH CIRCULARLYPOLARIZED LIGHT. . WAVELENGTH DEPENDENCE OF THE OPTICAL YIELD OFOCTAHELICENE.

Description: The synthesis of nonracemic yields of hexa-, hepta-, octa-, and nonhelicene with circular light was observed, and the structural and wavelength dependence of the induced optical yields was examined. The results obtained, together with a detailed consideration of the mechanism of helicene synthesis from the parent diarylolefins, indicate that the induced optical activity is due to selective reaction of enantiomeric conformations of the parent cis diarylolefins by circular light.
Date: May 1, 1971
Creator: Bernstein, William J.; Calvin, Melvin & Buchardt, Ole.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SPECIFIC PROTONATION OF THE CARCINOGEN 7, 12-DIMETHYIBENZ [a]ANTHRACENE AND CHARGE LOCALIZATION IN THE a-COMPLEX

Description: In the class of the polycondensed aromatic hydrocarbons, the concept of localized charge in a {sigma}-complex, e.g., the carbonium ion formed by addition of a proton or other electrophile to an aromatic ring, has so far received experimental evidence only in the case of anthracene. The ultraviolet spectrum of this compound in sulfuric acid is similar to that of the benzhydryl cation. Ph{sub c}C{sup +}Me. This result implies the protonation of anthracene at one meso-carbon atom and the localizat… more
Date: April 1, 1971
Creator: Cavalieri, Ercole & Calvin, Melvin.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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PHOTOCHEMICAL COUPLING OF BENZO [a]PYRENE WITH 1-METHYL-CYTOSINE;PHOTO-ENHANCEMENT OF CARCINOGENICITY

Description: Irradiation of the carcinogenic benzo[a]pyrene (I) with 1-methylcytosine hydrochloride IIa (molar ratio 1:10) at 3500 {angstrom} in methanol-acetone produces the 6-(1-methylcytos-5-yl)-benzo[a]pyrene (III). The structure of the product shows the hydrocarbon bound through the most active 6-carbon atom to the nucleophilic 5-position of the base. In the second part, the possibility of observing carcinogenic effects on the mouse skin from non-carcinogenic hydrocarbons under the action of UV light i… more
Date: January 1, 1971
Creator: Cavalieri, E. & Calvin, Melvin.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanism Op Action Op P-Hydroxybenzoate Hybrozylase Frompseudomonas Putida. Iii. The Enzyme-Subtrate Complex

Description: The mechanism of action of p-hydroxybenzoate hydroxylase from Pseudomonas putida, strain M-6, has been investigated. The aromatic substrate analogues, benzoate, p-fluorobenzoate, p-chlorobenzoate, p-nitrobenzoate, p-aminobenzoate, and 6-hydroxynicotinate, are found to be competitive inhibitors. This finding differs from the previously reported noncompetitive behavior in a different buffer system. The optical activity of the enzyme-inhibitor complex is studied. From the kinetic and circular dich… more
Date: April 1, 1971
Creator: Teng, Nelson N. H.; Kbtovycz, George; Calvin, Melvin & Hosokawa, Keiichi
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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BEAM-SURROUNDING INTERACTIONS AND THE STABILITY OF RELATIVISTIC PARTICLE BEAMS

Description: In accord with recent custom, the organizing committee for this conference has scheduled this review paper on beam instabilities. In view of the various review papers which already exist and the fact that the fundamentals of the subject have even been treated in a textbook, I thought this paper might best be devoted to a limited part of the rather large field of beam instabilities. Thus, I have selected only an aspect of the general subject, but an aspect which has during the last years been ve… more
Date: February 1, 1971
Creator: Sessler, Andrew M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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An Analog Method for Measuring the Longitudinal Coupling Impedance of a Relativistic Particle Beam With Its Environmnet

Description: The stability of a coasting beam against self-bunching (negative mass instability) may be expressed in terms of a beam coupling impedance. The impedance has contributions from self-fields, wall impedance, and curvature effects. This paper describes procedures for measuring the wall and curvature contributions to the coupling impedance by means of an analog in which the beam is replaced by a conductor propagating a TEM-like mode. Conditions are derived under which the measurements are valid, var… more
Date: August 1, 1971
Creator: Faltens, A.; Hartvig, E. C.; Mohl, D. & Sessler, A. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ORBITAL SYMMETRY CONTROL IN THE NITRONE-OXAZIRIDINE SYSTEM.NITRONE PHOTOSTATIONARY STATES

Description: Recent the orbital symmetry rules have been shown to apply to hetero-atom systems such as nitrone thermal cycloaddition reactions and the thermal and photochemical aziridine ring cleavage at the C-C bond. The concerted photocyclization is disrotatory and the reverse thermal cleavage is conrotatory in these molecules with four {pi} electrons. In contrast to the azomethine ylide-aziridine system, the stereochemistry of the nitrone photocyclization to oxaziridine can only be observed on carbon and… more
Date: June 1, 1971
Creator: Splitter, Janet S.; Su, Tah-mun; Ono, Howard & Calvin, Melvin.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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SPECTROSCOPIC INVESTIGATION OF THE INHIBITORY EFFECT OF FATTYACIDS ON PHOTOSYNTHETIC SYSTEMS

Description: Fatty acids have a reversible inhibitory effect on respiration and on photosynthetic action. They investigated the influence of octanoic acid on the photosynthetic bacteria Rhodopseudomonas spheroids R-26. From the spectroscopic data they conclude that a less efficient energy transfer and decoupling of the light harvesting pigment system from the energy converting reaction center is responsible for the inhibitory effect.
Date: May 1, 1971
Creator: Steffea, Hans & Calvin, Melvin.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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THE EFFECT OF RIFAMPICIN, AND TWO DERIVATIVES, ON CELLS INFECTEDWITH MOLONEY SARCOMA VIRUS

Description: It is shown that rifampicin, and especially its relative dimethyl-N-benzyl-N-desmethyl rifampicin, can inhibit focus formation by Moloney sarcoma virus on BALB/3T3 tissue cultures. At a dose level of 10 {micro}g/ml DMB appears to totally inhibit focus formation while reducing virus replication by at least a factor of fifty and cell proliferation by only a factor of three. These observations, taken together with those of others, suggest a role for the hybrid RNA-DNA dependent DNA polymerase and … more
Date: March 1, 1971
Creator: Calvin, Melvin.; Joss, Urs R.; Hackett, Adeline J. & Owens, RobertB.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Manual of data-analysis programs for charged-particle reactions. [AUTOFIT, for fitting emulsion data]

Description: This report contains additions and changes to the original report. Most of the changes relate to improvements in the programs. In addition to the changes, Section VII of the original report, Program AUTOFIT, is reproduced in its entirety. (RWR)
Date: September 1, 1971
Creator: Comfort, J.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dissipation of the reactor heat at the Savannah River Plant

Description: The effluent cooling water from the heat exchangers of the Savannah River nuclear reactors is cooled by natural processes as it flows through the stream beds, canals, ponds, and swamps on the plant site. The Langhaar equation, which gives the rate of heat removal from the water surface as a function of the surface temperature, air temperature, relative humidity, and wind speed, is applied satisfactorily to calculate the cooling that occurs at all temperature levels and for all modes of water fl… more
Date: October 1, 1971
Creator: Neill, J. S. & Babcock, D. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geothermal resource investigations, Imperial Valley, California. Status report

Description: The discussion is presented under the following chapter titles: geothermal resource investigations, Imperial Valley, California; the source of geothermal heat; status of geothermal resources (worldwide); geothermal aspects of Imperial Valley, California; potential geothermal development in Imperial Valley; environmental considerations; and proposed plan for development. (JGB)
Date: April 1, 1971
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Waukegan Station plume

Description: In a previous report on effects of thermal discharges from power plants into the Great Lakes, we stressed the need for a statistical analysis of the spatial and temporal pattern of the thermal plume. The plume pattern is recognized as stochastic in nature and requires statistical analysis. A single realization of the Waukegan Station plume is studied with emphasis on its information content. Areas between isotherms at various depths are computed together with volumes of water in given temperatu… more
Date: May 1, 1971
Creator: Abu-Shumays, I.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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