Revisit cosmic ray propagation by using 1^{1}H, 2^{2}H, 3^{3}He and 4^{4}He

The secondary-to-primary ratios are unique tools to investigate cosmic ray propagation mechanisms. In this work, we use the latest data of deuteron-to-helium~4 ratio and helium~3-to-helium~4 ratio measured by PAMELA combined with other Z$\leq$2 primary fluxes measured by PAMELA and Voyager-1, to constrain the cosmic ray acceleration and propagation models. The analysis is performed by interfacing statistical tools with the GALPROP propagation package. To better fit both the modulated and unmodulated low energy cosmic ray data, we find that a time-, charge- and rigidity-dependent solar modulation model is better than the force-field approximation. Among all the studied cosmic ray propagation models, the diffusion-reacceleration-convection model is strongly supported by the derived Bayesian evidence. The robustness of the estimated diffusion slope $\delta$ is cross-checked by another low-mass secondary-to-primary ratio, i.e. the antiproton-to-proton ratio. It is shown that the diffusion-reacceleration-convection model can reconcile well with the high energy antiproton-to-proton ratio. This indicates that the estimated value of $\delta$ is reliable. The well constraint $\delta$ from the `best' model is found to be close to 1/3, inferring a Kolmogorov-type interstellar magnetic turbulence.Comment: Accepted by Physics Letters

Teleportation of an arbitrary multipartite state via photonic Faraday rotation

We propose a practical scheme for deterministically teleporting an arbitrary multipartite state, either product or entangled, using Faraday rotation of the photonic polarization. Our scheme, based on the input-output process of single-photon pulses regarding cavities, works in low-Q cavities and only involves virtual excitation of the atoms, which is insensitive to both cavity decay and atomic spontaneous emission. Besides, the Bell-state measurement is accomplished by the Faraday rotation plus product-state measurements, which could much relax the experimental difficulty to realize the Bell-state measurement by the CNOT operation.Comment: 11 pages, 2 figures

Mechanisms in non-heme iron oxidation catalysis:Photochemistry and hydrogen peroxide activation

In dit proefschrift focussen we voornamelijk op de fotoactivatie van niet-heem ijzercomplexen en de mechanismen van thermische reacties van niet-heem ijzercomplexen met H2O2. Hoofdstukken 2, 3 en 4 focussen op de fotochemische activatie van ijzercomplexen in de Fe(IV)- en Fe(II)oxidatietoestanden. In hoofdstuk 2 worden de activatie van niet-heem ijzer(IV)-oxo-complexen en de bijbehorende mechanismen onderzocht. In hoofdstuk 3 laat de aerobe fotokatalytische oxidatie van methanol zien dat het fotoactieve niet-heem -oxo-di-ijzercomplex een rol speelt in het mechanisme van fotodisproportionering van het di-ijzer(III)complex. In hoofdstuk 4 wordt de oxidatieve fotodegradatie van niet-heem ijzer-polypyridyl-complexen onder basische omstandigheden onderzocht, en worden de implicaties van de getrokken conclusies met betrekking tot ligandontwerp bediscussieerd. Hoofdstukken 5 en 6 focussen op het mechanisme van thermische generatie van hoogvalente ijzer(IV)-oxo-complexen door reactie van niet-heem ijzer(III) met H2O2. In hoofdstuk 5 wordt gefocust op de vorming van hoogvalente ijzer(IV)-oxo-complexen via de heterolyse van een O-O binding in een Fe(II)-OOH-complex. Dit Fe(II)-complex werd gevormd met een stoichiometrische hoeveelheid H2O2. In hoofdstuk 6 wordt een nieuwe mechanistische route gedemonstreerd voor de reactie van Fe(III)OOH-complexen met H2O2. Deze route is kinetisch gunstiger dan de homolytische scheiding van de Fe(III)OOH O-O binding, waarbij hoogvalente ijzer(IV)-oxo-complexen ontstaan. Er wordt gedemonstreerd dat de beschreven mechanistische routes nadelig zijn voor de katalytische oxidatie van organische substraten.In this thesis, we focus mainly on the photo activation non-heme iron complexes, as well as mechanisms of thermal reactions of non-heme iron complex with H2O2. Chapter 2, 3 and 4, focus on photochemically induced activation of iron complexes in the Fe(IV) and Fe(III) oxidation states.In chapter 2, the direct activation of non-heme iron(IV)-oxo complexes and the mechanisms involved are explored. In chapter 3 the photo-catalytic oxidation of methanol under aerobic conditions reveals the involvement of a photo-active non-heme miu-oxo bridged diiron(III) complex and its mechanism for photo-induced disproportionation. In chapter 4, the photo-induced oxidative degradation of the non-heme iron polypyridyl complexes under basic conditions are explored and the implications the conclusions reached hold in regard to ligand design is discussed. Chapters 5 and 6 focus on the mechanism of thermal generation of high-valent iron(IV)-oxo complexes by reaction of non-heme iron(II) complexes with H2O2. In chapter 5, the generation of an iron(IV)-oxo complex via heterolysis of an O-O bond in an Fe(III)-OOH species formed with stoichiometric H2O2 is focused on. In chapter 6, a novel reaction pathway for the reaction of iron(III)-hydroperoxo species with H2O2 is established. This pathway is kinetically favored compared to the homolytic cleavage of the O-O bond in Fe(III)OOH, which would form high-valent iron(IV)-oxo species. The reaction pathways described are shown to be detrimental to the efficiency of the complexes in the catalytic oxidation of organic substrates