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LOW TEMPERATURE COOPERATIVE BEHAVIOR OF THE RARE EARTH SALTS GdCl$sub 3$ AND PrCl .
None
Date:
January 1, 1971
Creator:
Hessler, J.P.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
EVALUATION OF MULTILEVEL SPRINKLER SYSTEMS AND CONTAINER MATERIALS FOR FIRE PROTECTION IN HIGH-RACK STORAGE.
None
Date:
January 1, 1971
Creator:
Butturini, W. G.; DeMonbrun, J. R.; McCormick, J. W.; McLaughlin, L. M. & Weathersby, W. E.
Object Type:
Report
System:
The UNT Digital Library
Response of Shortgrass Plains Vegetation to Chronic and Seasonally Administered Gamma Radiation
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, July and December, 1969, respectively. Community structure was measured by coefficient of community and diversity index. Yield was determined by clipping plots in September 1970 and visual estimates in September 1969 and 1970 for the grass-sedge component of the vegetation. Individual species sensitivity was determined by density data recorded in April, June and September of 1969 and 1970 and by a phenological index recorded at weekly intervals during the 1969 and 1970 growing seasons. The response of the vegetation was similar whether determined by coefficient of community or diversity with diversity being a more sensitive measure of effects. In the chronically exposed sectors, the exposure rate which resulted in a 50 per cent reduction in these 2 parameters (CC50 or D50) was still …
Date:
August 1, 1971
Creator:
Fraley, L. Jr.
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Local Modification of Irradiation Conditions
None
Date:
January 1, 1971
Creator:
Miller, L. B. & Jarka, R. E.
Object Type:
Report
System:
The UNT Digital Library
ELECTRON TRANSFER REACTIONS OF FERROCENE.
None
Date:
January 1, 1971
Creator:
Pladziewicz, J R
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Irradiation Studies of Monobasic Saturated Carboxylic Acids in Non-Crystalline Hydrocarbon Matrices at 77$sup 0$K
None
Date:
September 1, 1971
Creator:
Bertin, E. P. & Burger, L. L.
Object Type:
Report
System:
The UNT Digital Library
Geothermal Resource Investigations: Imperial Valley, California. Site location report, deep geothermal test well
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 1,000 feet is irregular being shaped somewhat by ground-water movement. The area of greatest apparent heat flow is in SE/sup 1///sub 4/ of Sec. 6, T. 16 S., R. 17 E., and has a diameter of about /sup 1///sub 2/ mile. This area is an attractive drill site. The convective hydrothermal system regulating heat flow to the shallow subsurface is not known in detail but iso-resistivity maps suggest it exerts direct influence on near surface water temperature and salinity over an area of some 19 square miles. The mineral concentration of the ground water in this system will range from a minimum of about 3000 ppM to a probable maximum of about 30,000 ppM.
Date:
October 1, 1971
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
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
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 684 hours continuous test in a temperature range of 1050/sup 0/F to 1170/sup 0/F. The probes operated stably, repeatably and without undergoing performance changes.
Date:
June 1, 1971
Creator:
Hoogenboom, I. & Kissinger, C.
Object Type:
Report
System:
The UNT Digital Library
ABSOLUTE ASYMMETRIC SYNTHESIS. I. ON THE MECHANISM OF THEPHOTOCHEMICAL ABSOLUTE ASYMMETRIC SYNTHESIS OF HELICENES WITH CIRCULARLYPOLARIZED LIGHT. . WAVELENGTH DEPENDENCE OF THE OPTICAL YIELD OFOCTAHELICENE.
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.
Object Type:
Article
System:
The UNT Digital Library
SEARCH FOR MAGNETIC MONOPOLES IN LUNAR MATERIAL
None
Date:
June 1, 1971
Creator:
Eberhard, Philippe H.; Ross, Ronald R.; Alvarez, Luis W. & Watt,Robert D.
Object Type:
Article
System:
The UNT Digital Library
SPECIFIC PROTONATION OF THE CARCINOGEN 7, 12-DIMETHYIBENZ [a]ANTHRACENE AND CHARGE LOCALIZATION IN THE a-COMPLEX
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 localization of the positive charge at the other. The {sigma}-complex of the potent carcinogen 7,12-dimethylbenz[a]anthracene (DMBA) in acidic medium offers another example of this type of charge localization. The determination of structure was achieved by comparing the NMR spectra of DMBA in neutral and acidic solvents. The ratio of the integrated intensities of the proton peaks in the spectrum of DMBA is, from right to left, 3:3:5:1:1:2:1. The assignment of the 7-CH{sub 3} ({sigma}3.00) and 12-CH{sub 3} ({sigma}3.29) resonances was made by comparison with the spectra of 7-methylbenz[a]anthracene (7-CH{sub 3}, {sigma}3.03) and 12-methylbenz[a]anthracene (12-CH{sub 3}, {sigma}3.32) under the same conditions. A good general correlation exists between the methyl chemical shifts of the twelve monosubstituted methylbenzanthrancenes and the corresponding aryl protons of benzanthracene.
Date:
April 1, 1971
Creator:
Cavalieri, Ercole & Calvin, Melvin.
Object Type:
Report
System:
The UNT Digital Library
PHOTOCHEMICAL COUPLING OF BENZO [a]PYRENE WITH 1-METHYL-CYTOSINE;PHOTO-ENHANCEMENT OF CARCINOGENICITY
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 is investigated. Both experiments provide evidence that the 4,5-double bond (K region) of I presumably does not play a role in triggering the cancer process.
Date:
January 1, 1971
Creator:
Cavalieri, E. & Calvin, Melvin.
Object Type:
Report
System:
The UNT Digital Library
Mechanism Op Action Op P-Hydroxybenzoate Hybrozylase Frompseudomonas Putida. Iii. The Enzyme-Subtrate Complex
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 dichroism (CD) measurements, they have found that the carboxyl moiety is necessary and sufficient for the enzyme-substrate binding, whereas the hydroxyl group alone will not lead to binding. There are two classes of inhibitory analogues: one causes changes in CD spectra of the enzyme similar to those evoked by the substrate, and the other does not cause significant changes. the results indicate that more than one mode of enzyme-inhibitor interaction is involved. The CD of the enzyme-NADPH complex under anaerobic conditions suggests that the oxidized enzyme and reduced pyridine nucleotide form a complex, both in the absence and presence of the substrate, p-hydroxybenzoate. Furthermore, evidence for a ternary complex is given.
Date:
April 1, 1971
Creator:
Teng, Nelson N. H.; Kbtovycz, George; Calvin, Melvin & Hosokawa, Keiichi
Object Type:
Report
System:
The UNT Digital Library
BEAM-SURROUNDING INTERACTIONS AND THE STABILITY OF RELATIVISTIC PARTICLE BEAMS
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 very much at the center of activity, and will--if my judgment is correct--be even more so in the years to come. I wish to concentrate, here, on the interaction of a relativistic particle beam with itself which is a result of the coupling of the beam with its surroundings. Before approaching this topic, a few remarks on the existing review papers are in order. A comprehensive treatment of beam instabilities may be found in Ref. 1, where, also, the reader will find some 48 references to the original literature. In Refs. 2 and 3, the General subject is approached from other points of view. Reference 4 is concerned with some special topics, but treats …
Date:
February 1, 1971
Creator:
Sessler, Andrew M.
Object Type:
Article
System:
The UNT Digital Library
An Analog Method for Measuring the Longitudinal Coupling Impedance of a Relativistic Particle Beam With Its Environmnet
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, various measurement procedures are described and results of the application of the method to the compressor of an electron ring accelerator are reported.
Date:
August 1, 1971
Creator:
Faltens, A.; Hartvig, E. C.; Mohl, D. & Sessler, A. M.
Object Type:
Report
System:
The UNT Digital Library
ORBITAL SYMMETRY CONTROL IN THE NITRONE-OXAZIRIDINE SYSTEM.NITRONE PHOTOSTATIONARY STATES
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 nitrogen atoms because the oxygen atom has lone pair electrons instead of substituents. For the reverse thermal ring opening of oxaziridine to the nitrone, the two possible conrotatory motions of C-O bond cleavage should result in a mixture of the cis and trans-isomers of the nitrone, in contrast to the photoclosure which should be stereospecific.
Date:
June 1, 1971
Creator:
Splitter, Janet S.; Su, Tah-mun; Ono, Howard & Calvin, Melvin.
Object Type:
Article
System:
The UNT Digital Library
SPECTROSCOPIC INVESTIGATION OF THE INHIBITORY EFFECT OF FATTYACIDS ON PHOTOSYNTHETIC SYSTEMS
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.
Object Type:
Article
System:
The UNT Digital Library
THE EFFECT OF RIFAMPICIN, AND TWO DERIVATIVES, ON CELLS INFECTEDWITH MOLONEY SARCOMA VIRUS
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 the gene for its synthesis both in normal cell processes and in the transformation process.
Date:
March 1, 1971
Creator:
Calvin, Melvin.; Joss, Urs R.; Hackett, Adeline J. & Owens, RobertB.
Object Type:
Report
System:
The UNT Digital Library
The Crosbyton Review (Crosbyton, Tex.), Vol. 63, No. 13, Ed. 1 Thursday, April 1, 1971
Weekly newspaper from Crosbyton, Texas that includes local, state and national news along with advertising.
Date:
April 1, 1971
Creator:
Stockton, Billye
Object Type:
Newspaper
System:
The Portal to Texas History
The Tulia Herald (Tulia, Tex.), Vol. 63, No. 13, Ed. 1 Thursday, April 1, 1971
Weekly newspaper from Tulia, Texas that includes local, state and national news along with extensive advertising.
Date:
April 1, 1971
Creator:
Baggarly, H. M.
Object Type:
Newspaper
System:
The Portal to Texas History
The Tulia Herald (Tulia, Tex.), Vol. 63, No. 26, Ed. 1 Thursday, July 1, 1971
Weekly newspaper from Tulia, Texas that includes local, state and national news along with extensive advertising.
Date:
July 1, 1971
Creator:
Baggarly, H. M.
Object Type:
Newspaper
System:
The Portal to Texas History
The Crosbyton Review (Crosbyton, Tex.), Vol. 63, No. 26, Ed. 1 Thursday, July 1, 1971
Weekly newspaper from Crosbyton, Texas that includes local, state and national news along with advertising.
Date:
July 1, 1971
Creator:
Stockton, Billye
Object Type:
Newspaper
System:
The Portal to Texas History
The Clarksville Times (Clarksville, Tex.), Vol. 99, No. 21, Ed. 1 Thursday, July 1, 1971
Weekly newspaper from Clarksville, Texas that includes local, state, and national news along with advertising.
Date:
July 1, 1971
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History
The Clarksville Times (Clarksville, Tex.), Vol. 99, No. 11, Ed. 1 Thursday, April 1, 1971
Weekly newspaper from Clarksville, Texas that includes local, state, and national news along with advertising.
Date:
April 1, 1971
Creator:
unknown
Object Type:
Newspaper
System:
The Portal to Texas History