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81.
Laser Ablation Synthesis of Gold Selenides by using a Mass Spectrometer as a Synthesizer: Laser Desorption Ionization Time‐of‐Flight Mass Spectrometry 下载免费PDF全文
Dr. Lubomír Prokeš Prof. Pavel Kubáček Prof. Eladia Maria Peña‐Méndez Dr. Filippo Amato Prof. José Elias Conde Dr. Milan Alberti Prof. Josef Havel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(32):11261-11268
Methods for the rapid construction of new chemical motifs have the potential to accelerate the development of nanoscience. The synthesis of new chemical entities by laser ablation has been systematically demonstrated by using mixtures of gold and selenium. The compounds generated are detected by time‐of‐flight mass spectrometry and, for selected compounds, the structure is investigated by using density functional theory optimization. In total, 67 new gold selenide clusters have been synthesized, demonstrating an unsuspected richness in gold chemistry. Chemical species generated in the gas phase might inspire new routes for the synthesis of novel compounds in the solid state. 相似文献
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Keith E. Levine Li Han Andrea C. McWilliams Amal S. Essader Kelly E. Amato Reshan A. Fernando Donna B. Browning Lisa C. Greene David S. Ensor Nigel J. Walker Veronica G. Robinson Bradley J. Collins 《Mikrochimica acta》2014,181(1-2):171-179
The objective of this study was to characterize an assortment of as received, commercially available, non-functionalized multiwalled carbon nanotubes (MWCNT) samples (n?=?24) using thermogravimetric analysis, energy dispersive X-ray fluorescence spectrometry, high-resolution transmission electron microscopy and scanning electron microscopy. Each sample was assigned to one of six types based on nominal length and diameter. Some of the samples from the product assortment exhibited significant differences in purity and morphology from their nominal values. Variability in the physicochemical properties of MWCNTs may be a significant factor in why many toxicological investigations have findings that are difficult to reproduce. Therefore, it is strongly recommended that investigators studying these materials present characterization information in addition to providing their source. Figure
TGA and XRF purity by type of MWCNT sample. The objective of this study was to characterize an assortment of commercially available, non-functionalized of multiwalled carbon nanotubes (MWCNT) samples using thermogravimetric analysis, energy dispersive X-ray fluorescence spectrometry, high-resolution transmission electron microscopy and scanning electron microscopy. Variability in the physicochemical properties of MWCNTs may be a significant factor in why many toxicological investigations have findings that are difficult to reproduce. Therefore, it is strongly recommended that investigators studying these materials present characterization information with their research findings in addition to providing their source. 相似文献
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Wiesenmayer E Luetkens H Pascua G Khasanov R Amato A Potts H Banusch B Klauss HH Johrendt D 《Physical review letters》2011,107(23):237001
It is widely believed that, in contrast to its electron-doped counterparts, the hole-doped compound Ba(1-x)K(x)Fe(2)As(2) exhibits a mesoscopic phase separation of magnetism and superconductivity in the underdoped region of the phase diagram. Here, we report a combined high-resolution x-ray powder diffraction and volume-sensitive muon spin rotation study of Ba(1-x)K(x)Fe(2)As(2) showing that this paradigm does not hold true in the underdoped region of the phase diagram (0≤x≤0.25). Instead we find a microscopic coexistence of the two forms of order. A competition of magnetism and superconductivity is evident from a significant reduction of the magnetic moment and a concomitant decrease of the magnetoelastically coupled orthorhombic lattice distortion below the superconducting phase transition. 相似文献
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Mukai K Ikedo Y Nozaki H Sugiyama J Nishiyama K Andreica D Amato A Russo PL Ansaldo EJ Brewer JH Chow KH Ariyoshi K Ohzuku T 《Physical review letters》2007,99(8):087601
The magnetism of LixCoO2 (LCO), which has a similar structure to NaxCoO2 (NCO), has been investigated by muon-spin spectroscopy and susceptibility measurements using samples with x=0.1-1 prepared by an electrochemical reaction. In the x range below 0.75, LCO was found to be Pauli paramagnetic down to 1.8 K, suggesting an intermediate- or weak-coupling regime, although disordered local moments, with volume fractions below approximately 20%, appear at low T for LCO with x > or = 0.5. The phase diagram and interactions of LCO are thus strikingly different from NCO, while the differences cannot be explained simply by structural differences between the two systems. 相似文献