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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Propriétés électriques de l'InP in type p

Belache, Boukhalfa January 1989 (has links)
No description available.
42

Paramagnetic resonant-relaxation in potassium ferricyanide

Kipling, Arlin Lloyd January 1961 (has links)
No description available.
43

Gas-solid reaction analysis

Malus, Shem. January 2000 (has links)
No description available.
44

A pulsed magnet for high-field magnetization measurements /

Neufeldt, Bryan January 1989 (has links)
No description available.
45

Transmit antenna selected spatial multiplexing systems with power allocation

Shi, Zhengyan, 1975- January 2006 (has links)
No description available.
46

Toward Faster and Quieter MRI

Kidane, Tesfaye Kebede 15 June 2005 (has links)
No description available.
47

Calculation of Exchange and Anisotropy Energies in Single molecule magnets

Yu, Yongxue 02 December 2005 (has links)
No description available.
48

Multiple photonic responses in organic magnetic semiconductor

Yoo, Jung-Woo 05 January 2007 (has links)
No description available.
49

The phase space volume of ion clouds in Paul traps

Lunney, Matthew David Norwood January 1992 (has links)
A new technique is presented for measuring the spatial and momentum distributions of a buffer-gas cooled ion cloud in a Paul trap by extracting it from the trap and fitting the time profile of the extracted ion signal. A thermodynamic model based on the Gibbs distribution has been developed which describes the initial ion cloud phase space volume and fits the measured time distributions of the extracted cloud using only one parameter: temperature. A time-of-flight system has been built to systematically vary the ion extraction conditions and compare predictions of the model to various measurements of the ion cloud time profile. A new numerical method using a multipole expansion was developed to compute the extraction fields. Agreement between the ion simulations and the time-of-flight data is better than 2% of the total flight time. / Ion cloud temperatures were measured for seven different trap loadings of potassium ions and four loadings of sodium ions, in both cases down to clouds of about 1000 ions. This is the first time that temperature measurements have been made for such small numbers of buffer-gas cooled ions. The results show that the temperature of the ions above the buffer gas temperature appears to be proportional to the two-thirds power of the number of ions in the cloud. / Dynamic manipulation of the extracted ion cloud phase space volume was also accomplished using a time-varying acceleration voltage to change the ion cloud energy spread in flight. / A concept is also outlined to measure the detailed phase space area of the extracted cloud using the projection-slice theorem of tomographic imaging. / These measurements have applications for the use of ion traps as beam collectors for nuclear physics experiments at isotope separator facilities and possibly for nano-circuit fabrication.
50

Mass selective capture by an RFQ trap of externally injected ions

Davey, Louise January 1992 (has links)
A system for mass-selective capture of ions by a Paul trap was designed and tested. / An Paul trap and associated electronics have been assembled and tested, selectively trapping the ionic clusters C$ sp{+} sb2$ and C$ sp{+} sb3$ from a pulsed laser ion source. The ions were injected at 90 eV, trapped, extracted and detected, several parameters related to these processes were investigated. Simple models of the injection mechanism employed and for evaluating the pseudo-potential well depth of the ion trap are proposed. The overall efficiency of the ion injection system has been evaluated and compared to other methods of ion capture by an RFQ trap from an external source.

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