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Theoretical Studies of the Behavior of Ions in Aqueous Solutions of Mixed Electrolytes With Respect to Osmionic Cell Operation

Description: From Forward: "This is the seventy-sixth of a series of reports designed to present accounts of progress in saline water conversion with the expectation that the exchange of such data will contribute to the long-range development of economical processes applicable to large-scale, low-cost demineralization of sea or other saline water."
Date: July 1963
Creator: Murphy, George W. & Matthews, Robert R.
Partner: UNT Libraries Government Documents Department

Production of highly charged ion beams from ECR ion sources

Description: Electron Cyclotron Resonance (ECR) ion source development has progressed with multiple-frequency plasma heating, higher mirror magnetic fields and better technique to provide extra cold electrons. Such techniques greatly enhance the production of highly charged ions from ECR ion sources. So far at cw mode operation, up to 300 e{mu}A of O{sup 7+} and 1.15 emA of O{sup 6+}, more than 100 e{mu}A of intermediate heavy ions for charge states up to Ar{sup 13+}, Ca{sup 13+}, Fe{sup 13+}, Co{sup 14+} and Kr{sup 18+}, and tens of e{mu}A of heavy ions with charge states to Kr{sup 26+}, Xe{sup 28+}, Au{sup 35+}, Bi{sup 34+} and U{sup 34+} have been produced from ECR ion sources. At an intensity of at least 1 e{mu}A, the maximum charge state available for the heavy ions are Xe{sup 36+}, Au{sup 46+}, Bi{sup 47+} and U{sup 48+}. An order of magnitude enhancement for fully stripped argon ions (I {ge} 60 enA) also has been achieved. This article will review the ECR ion source progress and discuss key requirement for ECR ion sources to produce the highly charged ion beams.
Date: September 1, 1997
Creator: Xie, Z.Q.
Partner: UNT Libraries Government Documents Department

Carnotite-Bearing Sandstone in Cedar Canyon, Slim Buttes, Harding County, South Dakota

Description: A report about carnotite-bearing sandstone and clay which has been found in the Chadron formation of the White River group of Oligocene age in the southern part of the Slim Buttes area, Harding County, S. Dakota. The mineralized sandstone contains as much as 0.23 percent uranium.
Date: February 1954
Creator: Gill, J. R. & Moore, G. W.
Partner: UNT Libraries Government Documents Department

Free-ion spectra of interest to solid and solution spectroscopists

Description: A great deal of information is known about the free-ion spectra of the neutral and singly ionized rare earths because of the ease with which these spectra can be produced. Considerably less is known about the doubly and triply ionized rare earths. A discussion of the experimental difficulties, the present state of knowledge, and the predicted information are presented in this report. 6 references, 13 figures.
Date: January 1, 1985
Creator: Conway, J.G.
Partner: UNT Libraries Government Documents Department

Neutral H Atom and Molecular Ion (H₂⁺) Injection into the Mirror Machine at Energies About One Mev

Description: This report presents the best estimate possible on the basis of the available information as to how high an energy would be necessary in order that the gas pressure which could be tolerated would be attainable with present techniques (say 10-(-7) mm Hg.)
Date: May 11, 1956
Creator: Lauer, Eugene J. & Gibson, Gordon
Partner: UNT Libraries Government Documents Department

Microwave Diagnostics in ARC Research : On Determination of Physical Quantities of Gas Discharges in Ion-containment Machines by Measurement of Microwave Propagation Coefficient

Description: This report describes a method used to determine semi-quantitatively the time-varying plasma density in magnetic mirror machines by microwave phase-shift and attenuation measurement.
Date: April 1955
Creator: Post, Richard F.; Prosser, T. F. & Wharton, C. B.
Partner: UNT Libraries Government Documents Department

Dissociation of H₂⁺ by Photons

Description: Abstract: "A measurement was made of the dissociation of vibrationally-excited H2+ ions by photons having quantum energy in the vicinity of 4 e.v. The calculated cross section from theory is 3 x 10-(-18) cm-2. The experimental result is 10-(-17) cm-2; a factor of 10 uncertainty is present because the photon intensity was unknown by that factor."
Date: June 12, 1957
Creator: Linlor, William I.; Barnett, C. F. & Reinhardt, R.
Partner: UNT Libraries Government Documents Department

Overview of the current spectroscopy effort on the Livermore electron beam ion traps

Description: An overview is given of the current spectroscopic effort on the Livermore electron beam ion trap facilities. The effort focuses on four aspects: spectral line position, line intensity, temporal evolution, and line shape. Examples of line position measurements include studies of the K-shell transitions in heliumlike Kr{sup 34+} and the 2s-2p intrashell transitions in lithiumlike Th{sup 87+} and U{sup 89+}, which provide benchmark values for testing the theory of relativistic and quantum electrodynamical contributions in high-Z ions. Examples of line intensity measurements are provided by measurements of the electron-impact excitation and dielectronic recombination cross sections of heliumlike transition-metal ions Ti{sup 20+} through CO{sup 25+}. A discussion of radiative lifetime measurements of metastable levels in heliumlike ions is given to illustrate the time-resolved spectroscopy techniques in the microsecond range. The authors also present a measurement of the spectral lineshape that illustrates the very low ion temperatures that can be achieved in an EBIT.
Date: June 29, 1995
Creator: Beiersdorfer, P.; Lopez-Urrutia, J.C. & Brown, G.
Partner: UNT Libraries Government Documents Department

Sputtered-ion source for the Lintott ion accelerator

Description: A sputtered ion source was developed for use with the commercial Lintott ion accelerator. This source is readily interchanged with the existing commercial sources, and it requires no modifications to the Lintott accelerator. Sample currents in excess of 15 microamps were produced for Al, Fe, Cu, and the refractory metal Ta. Design considerations and operating characteristics are discussed.
Date: May 1, 1976
Creator: Fuller, C. T.
Partner: UNT Libraries Government Documents Department

Highly-charged heavy-ion production with short pulse lasers

Description: This MathCAD document describes a possible approach using a PW -class short pulse laser to form a useful number (10{sup 12}) of high and uniform charge state ions with low ion temperature (<< 100 eV) and low momentum spread ({delta}p{sub z}/p, < 10{sup -4} ) for injection into heavy-ion fusion accelerators. As a specific example, we consider here Xenon{sup +26}, which has an ionization energy E{sub i} {approximately} 860 eV for the 26th electron, and a significantly higher ionization potential of 1500 eV for the 27th electron because of the M-shell jump. The approach considered here may be used for other ion species as well. The challenge is not simply to produce high charge states with a laser (the ITEP group [Sharkov] have used long pulse CO{sub 2} lasers to create many charge states of chromium up to helium-like Cr{sup +25} by collisional ionization at high Te), nor just to create such high charge states more selectively by field (tunneling) ionization at higher intensities and shorter pulses. Rather, the challenge is to create a selected uniform high charge state, in useful numbers, while keeping the ion temperature and momentum spread small, and avoiding subsequent loss of ion charge state due to recombination and charge-exchange with background gas atoms during extraction into a useful low emittance beam.
Date: January 27, 1998
Creator: Logan, G.; Bitmire, T.; Perry, M.; Anderson, O. & Kuehl, T.
Partner: UNT Libraries Government Documents Department

Midwest Tandem Cyclotron: A Proposal for a Regional Accelerator Facility

Description: Report issued by the Argonne National Laboratory discussing the proposal of the Midwest Tandem-Cyclotron accelerator facility. Descriptions of the facility designs, methods, and operations are presented. This report includes tables, illustrations, and photographs.
Date: June 1969
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department

Study of the effects of MeV Ag, Cu, Au, and Sn implantation on the optical properties of LiNbO{sub 3}

Description: The authors present the results of characterization of linear absorption and nonlinear refractive index of Au, Ag, Cu and Sn ion implantation into LiNbO{sub 3}. Ag was implanted at 1.5 MeV to fluences of 2 to 17 {times} 10 {sup 16}/cm{sup 2} at room temperature. Au and Cu were implanted to fluences of 5 to 20 {times} 10{sup 16}/cm{sup 2} at an energy of 2.0 MeV. Sn was implanted to a fluence of 1.6 {times} 10{sup 17}/cm{sup 2} at 160 kV. Optical absorption spectrometry indicated an absorption peak for the Au implanted samples after heat treatment at 1,000 C at 620 nm. The Ag implanted samples absorption peaks shifted from 450 nm before heat treatment to 550 nm after 500 C for 1h. Heat treatment at 800 C returned the Ag implanted crystals to a clear state. Cu nanocluster absorption peaks disappears at 500 C. No Sn clusters were observed by optical absorption or XRD. The size of the Ag and Au clusters as a function of heat treatment were determined from the absorption peaks. The Ag clusters did not change appreciably in size with heat treatment. The Au clusters increased from 3 to 9 nm diameter upon heat treatment at 1000 deg C. TEM analysis performed on a Au implanted crystal indicated the formation of Au nanocrystals with facets normal to the c-axis. Measurements of the nonlinear refractive indices were carried out using the Z-scan method with a tunable dye laser pumped by a frequency doubled mode-locked Nd:YAG laser. The dye laser had a 4.5 ps pulse duration time and 76 MHz pulse repetition rate (575 nm).
Date: February 1, 1998
Creator: Williams, E.K.; Ila, D.; Sarkisov, S.; Curley, M.; Poker, D.B.; Hensley, D.K. et al.
Partner: UNT Libraries Government Documents Department

A study of transient molecular ions using a resonant microwave cavity as a probe

Description: The microwave-resonant-cavity technique was employes as a probe to determine the presence of molecular ions of helium in a d.c.-discharge, helium-plasma filament placed coaxially in a TM010 mode cavity. The cavity-resonance profile was displayed on an oscilloscope, and the nature of the perturbation of this resonance was used to determine the nature of the ions present in the plasma stream.
Date: December 1973
Creator: Congleton, Michael William
Partner: UNT Libraries

Cyclotron Resonance Heating of a Deuterium Plasma

Description: Abstract: "The energy gained by a deuterium plasma, from a three megacycle per second radiofrequency field, was studied experimentally. A static magnetic field, in the form of a "mirror", was used. The coil of an rf resonant circuit, placed at the center of the machine produced a time-varying magnetic field parallel to the static field. This, in turn, induced an electrical field, in an azmuthal direction, which acted on the ions. When this was in synchronism with the cyclotron frequency, the ions could pick up energy. At this resonance the light intensity from the plasma increased markedly. This effect was used as evidence for the transfer of energy to the ions."
Date: October 28, 1957
Creator: Chambers, Edmund S.; Lamb, William A. S. & Kippenhan, Dean O.
Partner: UNT Libraries Government Documents Department

The Effect of Geometry and Voltage Variations on the Operations of the Phillips Ion Gage

Description: Abstract: "The study of ten P.I.G. geometries with copper electrodes and d.c. voltage indicates that from a pressure of 0.1 to about 3.0 microns, depending upon the gage, there is a consistent change in the air pressure-current characteristics of a P.I.G. as the geometry and voltage are changed. At higher pressures discontinuities appear in the gage current and prohibit its use as a pressure gage. In all useful geometries, the greater the applied voltage above 1000 volts, the shorter the useful portion of the pressure-current curve became. Below 1000 volts the curve tended to be unstable. With other conditions constant, the pressure limit increased as the cathode separation decreased and as the anode diameter increased. The empirical equation for the current in certain Philips Ion Gages at certain pressures and voltages is I = a'Pe-p/b where I is the current, P the pressure, e the Naperian base and a' and b constants and dependent upon geometry and voltage."
Date: August 22, 1945
Creator: McKinney, C. R.; Eggen, Donald T.; Bishop, A.; Arnold, W. A. & Starr, C.
Partner: UNT Libraries Government Documents Department

The Ion Velocitron

Description: This report analyzes the separation of ions using the velocity of the ion measured through a long evacuated drift tube.
Date: January 27, 1947
Creator: Cameron, A. E. & Eggers, D. F.
Partner: UNT Libraries Government Documents Department

The Longitudinal Stability of Intense Non-Relativistic Particle Bunches in Resistive Structures

Description: The longitudinal stability of intense particle bunches is investigated theoretically in the limit of small wall resistivity compared to total reactance. It is shown that both in the absence of resistivity and to lowest order in the resistance that an intense bunch is stable against longitudinal collective modes. An expression is derived for the lowest order instability rate. Application of these results are made to drivers for heavy ion inertial fusion.
Date: February 1, 1981
Creator: Channell, P. J.; Sessler, A. M. & Wurtele, J. S.
Partner: UNT Libraries Government Documents Department

HULLAC-based Simulations of Non-LTE Emission Spectra

Description: This document describes the calculations I have carried out to synthesize spectra for test cases Ar1, Ge1, Ba1 and Au1. First, a brief description of how HULLAC generates atomic data is presented. Next, the implementation of those data in a collisional-radiative (CR) model is described. Two approaches are taken: First, the HULLAC data are entered into the CR rate matrix, and the relative populations of each ion charge state as given by an off-line Monte Carlo calculation are used to constrain the resulting level populations. Alternatively, the HULLAC data-filled CR rate matrix is inverted with out constraining the relative ion populations; the resulting average ion charge &lt; Z &gt; is significantly different between the two calculations. My resulting b-b, b-f and f-f emission spectra are presented in figures.
Date: April 12, 2001
Creator: Fournier, K B
Partner: UNT Libraries Government Documents Department