6 Matching Results

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Investigation of the validity of the OZI rule and study of production properties of the anti K*/sup. / resonance in. pi. /sup +/p interactions at 16 GeV/c (open access)

Investigation of the validity of the OZI rule and study of production properties of the anti K*/sup. / resonance in. pi. /sup +/p interactions at 16 GeV/c

Results are reported from a streamer chamber experiment performed at Stanford Linear Accelerator Center (SLAC) to study the production of the phi (1020) in OZI-allowed and forbidden processes in ..pi../sup +/p interactions at 16 GeV/c. Production properties of the anti K*/sup ./(896) are also studied and discussed.
Date: September 1, 1981
Creator: Jawahery, A.
System: The UNT Digital Library
Mass-spectrometric determination of trace elements in aqueous media without preconcentration (open access)

Mass-spectrometric determination of trace elements in aqueous media without preconcentration

Feasibility of using a low pressure glow discharge as an ion source for the mass spectrometric determination of trace elements in aqueous media was investigated. A cryogenically cooled hollow cathode ion source was developed to analyze aqueous samples without external preconcentration. Aqueous solutions containing seventy elements were analyzed and the detection limits, sensitivity factors, and linear regression correlation coefficients were determined. A standard test solution of trace elements in water was analyzed and the concentrations of trace elements were calculated using the sensitivity factors determined previously. The results compared favorably within the error limits predicted by the semiquantitative survey methods used. Tap water and natural lake water samples were examined and minimal interference effects due to organic compounds and biological compounds were noted. A research ion optical system (RIOS) was developed as a flexible mass analyzer for the development of new ion sources. The RIOS is a double focussing mass analyzer designed utilizing the Mattauch-Herzog geometry with externally adjustable slit assemblies.
Date: October 1, 1981
Creator: Foss, G. O.
System: The UNT Digital Library
Production of chi mesons in 225 GeV/c. pi. /sup -/Be interactions (open access)

Production of chi mesons in 225 GeV/c. pi. /sup -/Be interactions

Gamma rays associated with psi mesons have been studied in 225 GeV/c ..pi../sup -/Be interactions. The psi-..gamma.. mass spectrum shows an excess of 47 +- 11 events above background centered at 3.531 GeV/c/sup 2/ with an rms width of 22.4 MeV. Attributing this excess of events to the decay chi ..-->.. psi ..gamma.. implies that 38 +- 9 % of all psi mesons are produced by this mechanism. The experimental setup and results are detailed.
Date: September 1, 1981
Creator: Hossain, S.
System: The UNT Digital Library
Influence of lead ions on the macromorphology of electrodeposited zinc (open access)

Influence of lead ions on the macromorphology of electrodeposited zinc

The morphology of zinc as it is electrodeposited from acid solutions demonstrates a remarkable imprint of electrolyte flow conditions. The development of macromorphology of zinc deposits has been investigated under galvanostatic conditions on a rotating plantinum disk electrode by use of photomacrography, scanning electron microscopy, electron probe microanalysis and Auger microprobe analysis. Logarithmic spiral markings, which reflect the hydrodynamic flow on a rotating disk, appear in a certain region of current density well below the limiting current density. Morphological observations revealed the major influence of trace lead ions on the amplifications of surface roughness through coalescence and preferred growth of initial protrusions. Results obtained from ultra-pure electrolyte suggest preferred crystal growth towards well-mixed orientation in the concentration field caused by slight differences in crystallization overpotential. A qualitative model involving a coupling mechanism between the evolving surface roughness and instability phenomena in the boundary layer is advanced to explain the formation of spiral patterns.
Date: September 1, 1981
Creator: Tsuda, T. & Tobias, C.W.
System: The UNT Digital Library
High pressure HC1 conversion of cellulose to glucose (open access)

High pressure HC1 conversion of cellulose to glucose

The production of ethanol from glucose by means of fermentation represents a potential long-range alternative to oil for use as a transportation fuel. Today's rising oil prices and the dwindling world supply of oil have made other fuels, such as ethanol, attractive alternatives. It has been shown that automobiles can operate, with minor alterations, on a 10% ethanol-gasoline mixture popularly known as gasohol. Wood has long been known as a potential source of glucose. Glucose may be obtained from wood following acid hydrolysis. In this research, it was found that saturating wood particles with HCl gas under pressure was an effective pretreatment before subjecting the wood to dilute acid hydrolysis. The pretreatment is necessary because of the tight lattice structure of cellulose, which inhibits dilute acid hydrolysis. HCl gas makes the cellulose more susceptible to hydrolysis and the glucose yield is doubled when dilute acid hydrolysis is preceded by HCl saturation at high pressure. The saturation was most effectively performed in a fluidized bed reactor, with pure HCl gas fluidizing equal volumes of ground wood and inert particles. The fluidized bed effectively dissipated the large amount of heat released upon HCl absorption into the wood. Batch reaction times of one …
Date: August 1, 1981
Creator: Antonoplis, Robert Alexander; Blanch, Harvey W. & Wilke, Charles R.
System: The UNT Digital Library