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Phosphine Substitution in n5-Cyclopentadienyl-Bis-Triphenylphosphinecobalt (I): Evidence for a Dissociative Mechanism (open access)

Phosphine Substitution in n5-Cyclopentadienyl-Bis-Triphenylphosphinecobalt (I): Evidence for a Dissociative Mechanism

The substitution of trimethylphosphine for triphenylphosphine in {eta}{sup 5}-cyclopentadienyl-bis-triphenylphosphinecobalt(I), 1, to form {eta}{sup 5}-cyclopentadienyltrimethylphosphinetriphenylphosphinecobalt(I) was studied at -60°C in an NMR spectrometer. Kinetic measurements show the process to be first order in 1 and zero order in PMe{sub 3}; added PPh{sub 3} strongly inhibits the reaction rate. This information indicates the reaction proceeds by rapid reversible phosphine dissociation through the unsaturated CpCo(PPh{sub 3}) intermediate. The rate for generation of that intermediate, k{sub 1}, is 1.15 x 10{sup -3} sec{sup -1} while the ratio of rate constant k{sub 2} (for conversion of intermediate to products) to k{sub -1} (return to starting materials) is 4 at -60°C. Possible structures for CpCo(L) are discussed in light of recent indications that the linear structure has an open-shell electronic configuration.
Date: June 1, 1980
Creator: Janowicz, Andrew H.; Bryndza, Henry E. & Bergman, Robert G.
Object Type: Article
System: The UNT Digital Library
Nuclear structure studies at intermediate energies. Annual progress report, November 1979-October 1980. [Univ. of Minnesota, 11/79-10/80] (open access)

Nuclear structure studies at intermediate energies. Annual progress report, November 1979-October 1980. [Univ. of Minnesota, 11/79-10/80]

Research during the period November 1979 through October 1980 is reported. Completed work will be published in the usual places. Three sections containing significant amounts of information are abstracted separately. (RWR)
Date: January 1, 1980
Creator: Hintz, N. M.; Franey, M. A.; Gazzaly, M.; Cook, D.; Owen, K. & Overacker, L.
Object Type: Report
System: The UNT Digital Library
Southwest Retort, Volume 32, Number 8, April 1980 (open access)

Southwest Retort, Volume 32, Number 8, April 1980

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: April 1980
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Conservation in transportation (open access)

Conservation in transportation

A nationwide examination was made of grassroots energy conservation programs related to transportation. Information compiled from civic groups, trade associations, and corporations is included on driver awareness/mass transit; travel; and ride sharing. It is concluded that a willingness by the public to cooperate in transportation energy conservation exists and should be exploited. (LCL)
Date: May 30, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Role of fluctuations in the quantal description of damped motion (open access)

Role of fluctuations in the quantal description of damped motion

The construction of a frictional time-dependent Schroedinger equation is reviewed for harmonic motion in a restricted framework, i.e., demanding the conservation of the Gaussian shape of wave packets. The evolution of the quanta fluctuations is discussed in a time-independent model, and it is shown that such a situation does not correspond to damped harmonic oscillations. The role of fluctuations in providing dissipative behavior is discussed and the time evolution of arbitrary wave functions subject to damped motion as described by Schroedinger-Kostin equation is analyzed in detail.
Date: January 1, 1980
Creator: Hernandez, E. S.
Object Type: Report
System: The UNT Digital Library
Progress in research, January 1-December 31, 1979. [Dept. of Physics, Univ. of Texas, Austin] (open access)

Progress in research, January 1-December 31, 1979. [Dept. of Physics, Univ. of Texas, Austin]

Research in theoretical nuclear physics during 1979 is reported. Areas of research included the following: reactions induced by low-energy light ions, heavy-ion-induced reactions, medium-energy physics, and nuclear collective motions. From the extensive list of references one may assume that completed work has been or will be published in the usual channels. 34 figures. (RWR)
Date: January 1, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Rice Thresher (Houston, Tex.), Vol. 68, No. 8, Ed. 1 Thursday, September 25, 1980 (open access)

The Rice Thresher (Houston, Tex.), Vol. 68, No. 8, Ed. 1 Thursday, September 25, 1980

A weekly student newspaper from the Rice University in Houston, Texas that includes campus news and commentaries along with advertising.
Date: September 25, 1980
Creator: Dees, Richard
Object Type: Newspaper
System: The Portal to Texas History
Assessment of US shipbuilding current capability to build a commercial OTEC platform and a cold water pipe (open access)

Assessment of US shipbuilding current capability to build a commercial OTEC platform and a cold water pipe

Lowry and Hoffman Associates Inc. (LHA) performed for ORI an analysis of the shipbuilding requirements for constructing an OTEC plant, and the available shipyard assets which could fulfill these requirements. In addition, several shipyards were queried concerning their attitudes towards OTEC. In assessing the shipbuilding requirements for an OTEC plant, four different platform configurations were studied and four different designs of the cold water pipe (CWP) were examined. The platforms were: a concrete ship design proposed by Lockheed; concrete spar designs with internal heat exchangers (IHE) (Rosenblatt) and external heat exchangers (XHE) (Lockheed); and a steel ship design proposed by Gibbs and Cox. The types of materials examined for CWP construction were: steel, fiber reinforced plastic (FPR), elastomer, and concrete. The report is organized io three major discussion areas. All the construction requirements are synthesized for the four platforms and CWPs, and general comments are made concerning their availability in the US. Specific shipbuilders facilities are reviewed for their applicability to building an OTEC plant, an assessment of the shipyards general interest in the OTEC program is presented providing an insight into their nearterm commercial outlook. The method of determining this interest will depend largely on a risk analysis of …
Date: March 1, 1980
Creator: Komelasky, M. C.
Object Type: Report
System: The UNT Digital Library
Structures of adsorbed CO on atomically smooth and on stepped sngle crystal surfaces (open access)

Structures of adsorbed CO on atomically smooth and on stepped sngle crystal surfaces

The structures of molecular CO adsorbed on atomically smooth surfaces and on surfaces containing monatomic steps have been studied using the electron stimulated desorption ion angular distribution (ESDIAD) method. For CO adsorbed on the close packed Ru(001) and W(110) surfaces, the dominant bonding mode is via the carbon atom, with the CO molecular axis perpendicular to the plane of the surface. For CO on atomicaly rough Pd(210), and for CO adsorbed at step sites on four different surfaces vicinal to W(110), the axis of the molecule is tilted or inclined away from the normal to the surface. The ESDIAD method, in which ion desorption angles are related to surface bond angles, provides a direct determination of the structures of adsorbed molecules and molecular complexes on surfaces.
Date: January 1, 1980
Creator: Madey, T.E. & Houston, J.E.
Object Type: Article
System: The UNT Digital Library
The Rice Thresher (Houston, Tex.), Vol. 68, No. 9, Ed. 1 Thursday, October 2, 1980 (open access)

The Rice Thresher (Houston, Tex.), Vol. 68, No. 9, Ed. 1 Thursday, October 2, 1980

A weekly student newspaper from the Rice University in Houston, Texas that includes campus news and commentaries along with advertising.
Date: October 2, 1980
Creator: Dees, Richard
Object Type: Newspaper
System: The Portal to Texas History
Studies on the Biological Activity of N-nitrosamines (open access)

Studies on the Biological Activity of N-nitrosamines

Two aspects of the biological activity of N-nitrosamines were studied. First, the effect of ascorbate on the mutagenicity of N-nitrosopiperidines was studied in the Ames Salmanella/ mammalian microsome mutagenicity test. The addition of ascorbate significantly enhanced the mutagenicity of these compounds. This enhancement was selective for N-nitrosamines suggesting a possible role of ascorbate in N-nitrosamine induced carcinogenicity. Second, the technique of velocity sedimentation in alkaline sucrose density gradients was applied to the detection of N-nitrosamine induced DNA damage in Balb/c 3T3 cells. This technique detected N-nitrosamine induced DNA damage when the cells were made permeable before treatment. This technique compares favorably with other test systems used to evaluate N-nitrosamines and should be useful in further studies of N-nitrosamines.
Date: August 1980
Creator: Barton, Rodney A. (Rodney Alan)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Stability analysis of NbTi-Ta-based high field conductor cooled by pool boiling below 4 K (open access)

Stability analysis of NbTi-Ta-based high field conductor cooled by pool boiling below 4 K

Stability analysis has been performed for cabled NbTi-Ta-based superconductors intended for the high field (12 T) toroidal field coils for a large scale tokamak device such as ETF. Ternary NbTi-Ta was selected as the superconductor because of its superior critical current density at high field as compared to the binary alloy NbTi. The operating temperature was chosen to be 2.5 K or below to optimize the performance of the superconductor. A cabled conductor was selected to minimize the pulsed field losses. The conductor is cooled by pool boiling in a subcooled (approx. 2.5 K, 0.25 atm) bath, or in a superfluid helium (He-II) bath (approx. 1.8 K, 0.02 atm). The analysis was based on numerically simulating the evolution of a normal zone in the conductor. Appropriate superconductor properties and heat transfer characteristics were utilized in the simulation.
Date: September 1, 1980
Creator: Chen, W. Y.; Alcorn, J. S.; Hsu, Y. H. & Purcell, J. R.
Object Type: Article
System: The UNT Digital Library
LMFBR in-core thermal-hydraulics: the state of the art and US research and development needs (open access)

LMFBR in-core thermal-hydraulics: the state of the art and US research and development needs

A detailed critical review is presented of the literature relevant to predicting coolant flow and temperature fields in LMFBR core assemblies for nominal and non-nominal rod bundle geometries and reactor operating conditions. The review covers existing thermal-hydraulic models, computational methods, and experimental data useful for the design of an LMFBR core. The literature search made for this review included publications listed by Nuclear Science Abstracts and Energy Data Base as well as papers presented at key nuclear conferences. Based on this extensive review, the report discusses the accuracy with which the models predict flow and temperature fields in rod assemblies, identifying areas where analytical, experimental, and model development needs exist.
Date: April 1, 1980
Creator: Khan, E.U.
Object Type: Report
System: The UNT Digital Library
Study of structure of nuclei with neutrons and nuclear data measurements for MFE. Progress report, September 1, 1979-August 31, 1980 (open access)

Study of structure of nuclei with neutrons and nuclear data measurements for MFE. Progress report, September 1, 1979-August 31, 1980

Measurements of neutron differential elastic and inelastic scattering cross sections have been made for /sup 6/Li, /sup 7/Li, /sup 11/B and /sup 13/C. For /sup 7/Li + n, a multichannel R-matrix analysis has been completed, providing much new structure information for the compound /sup 8/Li system. These results are in very good agreement with recent theoretical model calculations, so that together the two provide considerable advancement in the state of our knowledge of /sup 8/Li. R-matrix analyses of /sup 11/B + n and /sup 13/C + n elastic scattering data have also been completed. For /sup 13/C + n theoretical model calculations have also been carried out and comparisons of these theoretical results with the R-matrix analysis are made. The triplet quadrupole spectrometer (TQS) is now fully operational. Development of new detectors, techniques, data analysis codes and theoretical model codes for use with the TQS system is complete. Measurements of (n,z) cross sections for fusion reactor structural materials e.g. /sup 58/Ni are currently underway. Construction of the long-flight-path tunnel for the swinger magnet facility has begun and development for this facility will continue in the coming year.
Date: January 1, 1980
Creator: Lane, R. O.
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 67, No. 14, Ed. 1 Monday, September 29, 1980 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 67, No. 14, Ed. 1 Monday, September 29, 1980

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: September 29, 1980
Creator: Lake, Charles S.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Geometry and Electronic Structure of (Co)3n1ch2. A Model Transition Metal Carbene (open access)

Geometry and Electronic Structure of (Co)3n1ch2. A Model Transition Metal Carbene

The first application of nonempirical molecular electronic structure theory to a realistic transition metal carbene complex is reported. The system chosen was (CO){sub 3}NiCH{sub 2}, methylene (tricarbonyl) nickel(0). All studies were carried out at the self-consistent-field (SCF) level. A large and flexibly contracted basis set was chosen, labeled Ni(15s 11p 6d/11s 8p 3d); C,O(9s 5p/4s 2p); H(5s/3s). In addition, the importance of methylene carbon d functions was investigated. The critical predicted equilibrium geometrical parameters were R [Ni-C (methylene)]=1.83 {Angstrom}, {theta}(HCH)=108°. The sixfold barrier to rotation about the Ni-C (methylene) axis is small, ~o.2 kcal. The electronic structure of (CO){sub 3}NiCH{sub 2} is discussed and compared with those of the "naked" complex NiCH{sub 2} and the stable Ni(CO){sub 4} molecule.
Date: April 1, 1980
Creator: Spangler, Dale; Wendoloski, John J.; Dupuis, Michel; Chen, Maynard M.L. & Schaefer, Henry F., III
Object Type: Article
System: The UNT Digital Library
Jewish Herald-Voice (Houston, Tex.), Vol. 72, No. 29, Ed. 1 Thursday, October 9, 1980 (open access)

Jewish Herald-Voice (Houston, Tex.), Vol. 72, No. 29, Ed. 1 Thursday, October 9, 1980

Weekly Jewish newspaper from Houston, Texas that includes local, state, and national news along with advertising.
Date: October 9, 1980
Creator: Samuels, Joseph W. & Samuels, Jeanne F.
Object Type: Newspaper
System: The Portal to Texas History
The Rice Thresher (Houston, Tex.), Vol. 68, No. 11, Ed. 1 Thursday, October 16, 1980 (open access)

The Rice Thresher (Houston, Tex.), Vol. 68, No. 11, Ed. 1 Thursday, October 16, 1980

A weekly student newspaper from the Rice University in Houston, Texas that includes campus news and commentaries along with advertising.
Date: October 16, 1980
Creator: Dees, Richard
Object Type: Newspaper
System: The Portal to Texas History
The Llano News (Llano, Tex.), Vol. 89, No. 9, Ed. 1 Thursday, January 3, 1980 (open access)

The Llano News (Llano, Tex.), Vol. 89, No. 9, Ed. 1 Thursday, January 3, 1980

Weekly newspaper from Llano, Texas that includes local, state, and national news along with advertising.
Date: January 3, 1980
Creator: Cunningham, T. H.
Object Type: Newspaper
System: The Portal to Texas History
Publications of LASL research, 1978 (open access)

Publications of LASL research, 1978

This bibliography is a compilation of unclassified publications of work done at the Los Alamos Scientific Laboratory for 1978. Papers published in 1978 are included regardless of when they were actually written. Publications received too late for inclusion in earlier compilations are also listed. Declassification of previously classified reports is considered to constitute publication. All classified issuances are omitted. If a paper was published more than once, all places of publication are included. The bibliography includes Los Alamos Scientific Laboratory reports, papers released as non-LASL reports, journal articles, books, chapters of books, conference papers (whether published separately or as part of conference proceedings issued as books or reports), papers published in congressional hearings, theses, and US patents. Publications by LASL authors that are not records of Laboratory-sponsored work are also included.
Date: April 1, 1980
Creator: Willis, J.K. & Salazar, C.A. (comps.)
Object Type: Report
System: The UNT Digital Library
The Llano News (Llano, Tex.), Vol. 89, No. 33, Ed. 1 Thursday, June 19, 1980 (open access)

The Llano News (Llano, Tex.), Vol. 89, No. 33, Ed. 1 Thursday, June 19, 1980

Weekly newspaper from Llano, Texas that includes local, state, and national news along with advertising.
Date: June 19, 1980
Creator: Cunningham, T. H.
Object Type: Newspaper
System: The Portal to Texas History
The Llano News (Llano, Tex.), Vol. 89, No. 35, Ed. 1 Thursday, July 3, 1980 (open access)

The Llano News (Llano, Tex.), Vol. 89, No. 35, Ed. 1 Thursday, July 3, 1980

Weekly newspaper from Llano, Texas that includes local, state, and national news along with advertising.
Date: July 3, 1980
Creator: Cunningham, T. H.
Object Type: Newspaper
System: The Portal to Texas History
The Llano News (Llano, Tex.), Vol. 89, No. 34, Ed. 1 Thursday, June 26, 1980 (open access)

The Llano News (Llano, Tex.), Vol. 89, No. 34, Ed. 1 Thursday, June 26, 1980

Weekly newspaper from Llano, Texas that includes local, state, and national news along with advertising.
Date: June 26, 1980
Creator: Cunningham, T. H.
Object Type: Newspaper
System: The Portal to Texas History
The Llano News (Llano, Tex.), Vol. 89, No. 31, Ed. 1 Thursday, June 5, 1980 (open access)

The Llano News (Llano, Tex.), Vol. 89, No. 31, Ed. 1 Thursday, June 5, 1980

Weekly newspaper from Llano, Texas that includes local, state, and national news along with advertising.
Date: June 5, 1980
Creator: Cunningham, T. H.
Object Type: Newspaper
System: The Portal to Texas History