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71.
W. von Oertzen B. Gebauer G. Efimov V. Zherebchevsky Tz. Kokalova S. Thummerer Ch. Schulz H. G. Bohlen D. Kamanin C. Beck D. Curien P. Papka M. Rousseau G. Royer G. de Angelis 《The European Physical Journal A - Hadrons and Nuclei》2008,36(3):279-288
Coincidences between two heavy fragments have been measured from the fission of 56Ni compound nuclei formed in the 32S + 24Mg reaction at E
lab( ^32S ) = 165.4 MeV. A unique experimental set-up consisting of two large-area position-sensitive (x, y) gas detector telescopes has been used allowing the complete determination of the observed fragments and their momentum vectors.
In addition to binary fission events with subsequent particle evaporation, narrow out-of-plane correlations are observed for
two fragments emitted in purely binary events and in events with a missing charge consisting of 2α - and 3α -particles (12C). These events are interpreted as ternary cluster decay from 56Ni nuclei at high angular momenta through hyper-deformed shapes. 相似文献
72.
P. Leproux V. Couderc A. de Angelis M. Okuno H. Kano H. Hamaguchi 《Journal of Raman spectroscopy : JRS》2011,42(10):1871-1874
We report, to the best of our knowledge, the first turn‐key and compact dual‐output sub‐nanosecond supercontinuum source applicable to ultrabroadband multiplex coherent anti‐Stokes Raman scattering microspectroscopy of biological samples. The light source design and the microspectroscopy setup are described in details. Easy multicolour imaging of Caenorhabditis elegans nematode is operated successfully and discussed. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
73.
74.
S. De Angelis Curtis Krystyna Kurdziel S. Materazzi S. Vecchio 《Journal of Thermal Analysis and Calorimetry》2008,92(1):109-114
The crystal structure of a manganese(II) 1-allylimidazole complex ([Mn(1-AIm)3(NO3)2], where 1-Aim=1-allylimidazole), was characterized by X-ray diffraction (XRD) using SHELX-97. The thermal behaviour of the
complex was investigated by thermogravimetry (TG) coupled with an FTIR unit. The complex showed a multi-step decomposition
related to the release of the ligand molecules, followed by oxidation. The final residue at 1073 K was found to be manganese(II)
oxide. Evolved gas analysis allowed to prove the oxidative decomposition pattern of the examined complex, initially proposed
by the percentage mass loss data. Finally, a kinetic analysis of the oxidative decomposition steps was made using the Kissinger
equation, while the complex nature of the decomposition kinetics was revealed by the isoconversional Ozawa-Flynn-Wall method. 相似文献
75.
We describe a simple, rapid combined method for extracting the antimalarial compound artemisinin from the leaves of Artemisia annua L. cultivated for the first time in Burundi, and quantitating the active principle by high-performance liquid chromatography-electrospray mass spectrometry. 相似文献
76.
Di Censo D Fantacci S De Angelis F Klein C Evans N Kalyanasundaram K Bolink HJ Grätzel M Nazeeruddin MK 《Inorganic chemistry》2008,47(3):980-989
Highly phosphorescent blue-light-emitting anionic iridium complexes (C4H9)4N[Ir(2-phenylpyridine)2(CN)2] (1), (C4H9)4N[Ir(2-phenyl-4-dimethylaminopyridine)2(CN)2] (2), (C4H9)4N[Ir(2-(2,4-difluorophenyl)-pyridine)2(CN)2] (3), (C4H9)4N[Ir(2-(2,4-difluorophenyl)-4-dimethylaminopyridine)2(CN)2] (4), and (C4H9)4N[Ir(2-(3,5-difluorophenyl)-4-dimethylaminopyridine)2(CN)2] (5) were synthesized and characterized using NMR, UV-vis absorption, and emission spectroscopy and electrochemical methods. In these complexes color and quantum yield tuning aspects are demonstrated by modulating the ligands with substituting donor and acceptor groups on both the pyridine and phenyl moieties of 2-phenylpyridine. Complexes 1-5 display intense photoluminescence maxima in the blue region of the visible spectrum and exhibit very high phosphorescence quantum yields, in the range of 50-80%, with excited-state lifetimes of 1-4 micros in acetonitrile solution at 298 K. DFT and time dependent-DFT calculations were performed on the ground and excited states of the investigated complexes to provide insight into the structural, electronic, and optical properties of these systems. 相似文献
77.
78.
79.
Georgakopoulos CG Vonaparti A Stamou M Kiousi P Lyris E Angelis YS Tsoupras G Wuest B Nielen MW Panderi I Koupparis M 《Rapid communications in mass spectrometry : RCM》2007,21(15):2439-2446
A new combined doping control screening method for the analysis of anabolic steroids in human urine using liquid chromatography/electrospray ionization orthogonal acceleration time-of-flight mass spectrometry (LCoaTOFMS) and gas chromatography/electron ionization orthogonal acceleration time-of-flight mass spectrometry (GCoaTOFMS) has been developed in order to acquire accurate full scan MS data to be used to detect designer steroids. The developed method allowed the detection of representative prohibited substances, in addition to steroids, at concentrations of 10 ng/mL for anabolic agents and metabolites, 30 ng/mL for corticosteroids, 500 ng/mL for stimulants and beta-blockers, 250 ng/mL for diuretics, and 200 ng/mL for narcotics. Sample preparation was based on liquid-liquid extraction of hydrolyzed human urine, and the final extract was analyzed as trimethylsilylated derivatives in GCoaTOFMS and underivatized in LCoaTOFMS in positive ion mode. The sensitivity, mass accuracy, advantages and limitations of the developed method are presented. 相似文献
80.
潘强岩 M.DE Poli G.De Angelis C.Fahander D.Bazzacco E.Farnea A.Gadea D.R.Napoli P.Spolaore 《原子核物理评论》1997,14(4):218-221
通过55Mn(30Si,αpn)反应布居了79Kr的高自旋态.用GASP阵列配以由40个ΔE×ESi(Au)望远镜所组成的带电粒子球实现γγγ-带电粒子符合测量.观测到由相对强度为(2.7±0.3)%的8条级联γ跃迁所组成的79Kr高自旋超形变转动带.除了在转动频率ω>0.95MeV处急剧下降外,该带的动力学转动惯量近乎常数(22ñ2/MeV)并被解释为具有四极形变参数β2=0.51以及本征侵入组态为π50ν51. High-spinstates in 79Kr were populated via the fusion evaporation reaction 55Mn (30Si,αpn)at 130 MeV.Promptγ γγ charged particle coincidences were measured by using the GASP array in conjunction with the ΔE×E Si(Au) charged particle ball.Asu perdeformed band consisting of 8 γ ray transitions with an intensity of (2.7±0.3)% has been indentified in 79Kr.The dynamic moment of inertia for the band is nearly constant at approxately 22ñ2/MeV below arotational frequency of 0.95 MeV... 相似文献