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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.
21

Estudo do poder de freamento eletrônico de íons de He e B canalizados em Si

Santos, Jose Henrique Rodrigues dos January 1997 (has links)
Neste trabalho, medimos a perda de energia de íons de He e B ao longo da direção < 100 > do Si, com energias que vão desde 200 ke V a 4,5 Me V, no primeiro caso, e de 500 ke V a 9 MeV, no segundo. Usamos a técnica de retroespalhamento de Rutherford com amostras do tipo SIMOX, as quais consistem de uma camada de Si monocristalino sobre uma camada de 500 nm de Si02 enterrada numa matriz de Si < 100 >. No método experimental empregado, a perda de energia dos íons canalizados é obtida depois de os mesmos serem retroespalhados em um marcador especialmente utilizado para esse fim. Para ambos os tipos de projétil, a curva da razão a entre os poderes de freamento de canalização e em direções aleatórias exibe um máximo largo e decresce lentamente a energias mais altas, em conseqüência do aumento da contribuição da camada L do Si para o poder de freamento eletrônico, como é indicado por cálculos de Aproximação de Born de Onda Plana (PWBA). / In this work, we have measured the electronic stopping power of He and B ions channeling along the < 100 > direction of Si crystals. The ion energies ranged between 200 keV and 4.5 Me V, in the first case, and between 500 ke V and 9 Me V, in the second one. We have used the Rutherford backscattering technique with SIMOX samples consisting of a Si single-crystal layer on top of a buried layer of 500 nm Si02 built into Si < 100 > wafer. In this exp erimental method, the channeling energy loss is obtained aft er the particles being backscattered at some marker specially used for this purpose . For both types of projectile, the curve of the a ratio between the channeling and random stopping powers has a broad maximum and decreases slowly at high energies dueto the increasing of the contribution of the Si L shell to the electronic stopping power, as indicated by Plane Wave Born Approximation (PWBA) calculations.
22

study in ion-trap systems. / 離子阱系統的研究 / A study in ion-trap systems. / Li zi jing xi tong de yan jiu

January 2008 (has links)
Chan, Chor Hoi = 離子阱系統的研究 / 陳楚海. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (p. 98-103). / Abstracts in English and Chinese. / Chan, Chor Hoi = Li zi jing xi tong de yan jiu / Chen Chuhai. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.1.1 --- Review of ion traps --- p.1 / Chapter 1.1.2 --- Review of entanglement in ion trap systems --- p.2 / Chapter 1.1.3 --- Review of RWA and MRWA --- p.3 / Chapter 1.2 --- Continuous frequency modes in different configurations --- p.5 / Chapter 1.2.1 --- Configuration 1: simple one sided cavity --- p.6 / Chapter 1.2.2 --- Configuration 2: displaced cavity --- p.8 / Chapter 1.3 --- Coupling strength in the continuous frequency mode model --- p.10 / Chapter 2 --- Motional Rotating Wave Approximation (MRWA) --- p.12 / Chapter 2.1 --- Introduction --- p.12 / Chapter 2.2 --- Trapped ion in a classical light field --- p.13 / Chapter 2.3 --- MRVVA and a rough estimation of the effect of non-resonant terms --- p.14 / Chapter 2.4 --- Numerical comparison between the MRWA solution and the exact solution --- p.17 / Chapter 2.5 --- Numerical results --- p.18 / Chapter 2.6 --- Calculation in the weak coupling and small η limit --- p.28 / Chapter 3 --- Generation of entanglement between photon and phonon --- p.32 / Chapter 3.1 --- Single-ion model --- p.32 / Chapter 3.2 --- Generation of entanglement between photon and phonon through Raman process --- p.35 / Chapter 3.2.1 --- Resolvent method --- p.35 / Chapter 3.2.2 --- Solutions in the limit \/T / ΩT ≤ / 2ΩT《1 --- p.38 / Chapter 3.2.3 --- The long time wave function --- p.40 / Chapter 3.2.4 --- Generation of entanglement in the first red or blue side-band resonance --- p.41 / Chapter 3.2.5 --- Discussion --- p.43 / Chapter 3.3 --- Generation of entanglement by photon scattering --- p.45 / Chapter 3.3.1 --- Resolvent and the scattering matrix --- p.45 / Chapter 3.3.2 --- The long time wave function --- p.48 / Chapter 3.3.3 --- Discussion --- p.50 / Chapter 4 --- Entanglement between vibrational states of separate ions --- p.55 / Chapter 4.1 --- The cascaded system model --- p.55 / Chapter 4.1.1 --- Introduction and basic ideas --- p.55 / Chapter 4.1.2 --- Resolvent and state evolution --- p.57 / Chapter 4.1.3 --- Time-dependent nature of the entanglement --- p.65 / Chapter 4.2 --- Feedback system --- p.69 / Chapter 5 --- Quantum State Transfer --- p.75 / Chapter 5.1 --- Scattering of a photon --- p.75 / Chapter 5.2 --- Cascaded system --- p.76 / Chapter 5.3 --- Feedback system --- p.78 / Chapter 5.4 --- N injected photons --- p.79 / Chapter 5.5 --- General case --- p.80 / Chapter 5.5.1 --- One injected photon --- p.82 / Chapter 5.5.2 --- N injected photons --- p.83 / Chapter 6 --- Generalization to two ion-chains --- p.85 / Chapter 7 --- Sources of errors --- p.88 / Chapter 7.1 --- Attenuation in optical fiber --- p.88 / Chapter 7.2 --- Inclusion of other states --- p.88 / Chapter 7.3 --- Effect of approximation (3.4) --- p.90 / Chapter 7.4 --- Spontaneous emission --- p.92 / Chapter 8 --- Conclusion --- p.97 / Bibliography --- p.98 / Chapter A --- sin[θ+ η](b + bt)] in Fock state basis --- p.104 / Chapter B --- Adiabatic elimination --- p.105 / Chapter C --- Derivation of the phase operator S in the feedback process --- p.112 / Chapter D --- Quantum trajectory method --- p.114
23

The stopping power of neon ions in aluminum

Shane, Kendahl Curtis January 2010 (has links)
Digitized by Kansas Correctional Industries
24

Experimental and theoretical aspects of hydrocarbon activation by transition metal ions in the gas phase

Schilling, J. Bruce. Goddard, William A., Beauchamp, Jesse L. January 1987 (has links)
Thesis (Ph. D.)--California Institute of Technology, 1987. UM #87-19,702. / Advisor names found in the Acknowledgements pages of the thesis. Title from home page. Viewed 01/15/2010. Includes bibliographical references.
25

Theoretical studies of ions in charged capillaries

盧偉賢, Lo, Wai-yin. January 1995 (has links)
published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy
26

The solvolysis of some allylic and homoallylic 2, 4- dinitrobenzoates

Lodwig, Siegfried Norbert, 1944- January 1971 (has links)
No description available.
27

CASCADE-FREE MEASUREMENTS OF ATOMIC MEAN-LIVES USING FAST-ION BEAMS AND TIME-CORRELATED SIGNALS

Masterson, Keith Dennis, 1940- January 1974 (has links)
No description available.
28

Charge transfer reactions of ions with neutral molecules

Wilcox, John Barrett 05 1900 (has links)
No description available.
29

Appearance energies and ion intensities of doubly charged n-alkanes

Jones, Billy Edward 05 1900 (has links)
No description available.
30

The occurrence and energetics of doubly charged ions in chlorinated and brominated alkanes

Hanner, Alfred Watt 08 1900 (has links)
No description available.

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