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A major deterioration in global climate occurred through the Eocene–Oligocene time interval, characterized by long-term cooling in both terrestrial and marine environments. During this long-term cooling trend, however, recent studies have documented several short-lived warming and cooling phases. In order to further investigate high-latitude climate during these events, we developed a high-resolution calcareous nannofossil record from ODP Site 748 Hole B for the interval spanning the late middle Eocene to the late Oligocene (~ 42 to 26 Ma). The primary goals of this study were to construct a detailed biostratigraphic record and to use nannofossil assemblage variations to interpret short-term changes in surface-water temperature and nutrient conditions. The principal nannofossil assemblage variations are identified using a temperate-war...
Treatments delivered by proton therapy are affected by uncertainties on the range of the beam within the patient, requiring medical physicists to add safety margins on the penetration depth of the beam. To reduce these margins and deliver safer treatments, different projects are currently investigating real-time range control by imaging prompt gammas emitted along the proton tracks in the patient. This study reports on the feasibility, development and test of a new concept of prompt gamma camera using a slit collimator to obtain a one-dimensional projection of the beam path on a scintillation detector. This concept was optimized, using the Monte Carlo code MCNPX version 2.5.0, to select high energy photons correlated with the beam range and detect them with both high statistics and sufficient spatial resolution. To validate the Monte C...
Comment: 9 pages, 5 figures. Accepted for publication on PoS, proceedings of "The Extreme sky: Sampling the Universe above 10 keV", held in Otranto (Italy), 13-17 October 2009
The donor-acceptor complexes [Fe(C5H5){C(5)H(4)QNHM(NO)(Tp(Me,Me))X}] {Tp(Me,Me) = tris(3,5-dimethylpyrazolyl) borate; Q = nothing, M = Mo, X = Cl, Br, I; M = W, X = Cl; Q = C6H4, M = Mo, X = Cl, Br, I; M = W, X = Cl; Q = CH=CHC6H4 or N=NC6H4, M = Mo, X = Cl), which contain 16-valence electron metal nitrosyl centres, [Fe(C5H5){C(5)H(4)QpyMo(NO)(Tp(Me,Me))Cl}] (py = 4-pyridyl; Q = CH=CH, CH=CHCO, N=CH and C6H4CH=CH), [Fe(C5Me4H){C5H4CH=CHpyMo(NO)(Tp(Me,Me))Cl}] and [Fe(C5Me4H)(C(5)Me(4)QpyZ)] {Q = CH=CH or CH=N, Z = Mo(NO)(Tp(Me,Me))Cl or W(CO)(5); Q=2,4-CH=CH(C4H2S) CH=CH, Z = W(CO)(5) or Me+I-}, some of which contain 17-valence electron molybdenum nitrosyl centres, and [Fe(C5Me4H){C5Me4CH=CH(C4H2S) CH=CHpy}], have been characterised electrochemically, by their electronic spectra, and spectroelectrochemically. Hyper-Rayleigh scattering...
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