The N(E) CKVV Auger spectra (with the X-ray excitation of the Auger emission) of carbon atoms of standard samples with the sp(2)-, sp(3)- and mixture of sp(2)/sp(3)-bonds and carbon containing contamination (CCC) have...
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The N(E) CKVV Auger spectra (with the X-ray excitation of the Auger emission) of carbon atoms of standard samples with the sp(2)-, sp(3)- and mixture of sp(2)/sp(3)-bonds and carbon containing contamination (CCC) have been studied. The Auger spectra of carbon atom samples with the sp(2)-, sp(3)- and mixture of sp2/sp3-bonds have a distinguishing feature due to the sigma- and pi -level positions in the valence band. The Auger spectra of CCC have inherent peculiarities due to chemical bonds (sp(3)) and electron energy losses. These data allow identification of the chemical bonds of carbon atoms on any carbon surface in situ as well as ex situ. The combination of CKVV, Cls and valence band XPS spectra was used to study chemical bonds for the depth of 2 / 10 monolayers. The surfaces of natural diamonds after polishing and H-plasma treatment and of ultra dispersion diamonds (UDD) were studied. The CKVV Auger spectra show that the carbon atoms on the surfaces of natural diamond after the H-plasma treatment as well as on UDD have a new unknown chemical state with sp(2)-bonds that differs in principle from that in graphite. This chemical state is a precursor for diamond nucleation and growth. Modifications of chemical bonds of carbon atoms on diamond surfaces, UDD and polyethylene during in situ Ar ion sputtering were identified.
A sensitive and rapid liquid chromatography-tandem mass spectrometry method has been developed for to assess therapeutic exposures of aprepitant in HIV-infected patients and rhesus macaques. The method utilized a simp...
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A sensitive and rapid liquid chromatography-tandem mass spectrometry method has been developed for to assess therapeutic exposures of aprepitant in HIV-infected patients and rhesus macaques. The method utilized a simple sample-preparation procedure of protein precipitation with methanol. Chromatographic separation was performed on a reversed phase C-8 column (Hypersil Gold, 50 mm x 2.1 mm, 3 mu m) using a mobile phase composed of acetonitrile and water in 0.5% formic acid through gradient elution. Electrospray ionization in positive mode was incorporated in the tandem mass spectrometric detection. The lower limit of quantitation of aprepitant in plasma of rhesus macaques and human and cerebral spinal fluid of rhesus macaques were 1, 1, and 0.1 ng/mL, respectively. The method has been successfully employed to measure aprepitant in preclinical and clinical samples collected from three SIV-infected rhesus macaques and ten patients with HIV infection. in conclusion, this liquid chromatography-tandem mass spectrometry method is suitable for preclinical-clinical translational research exploring exposure-response relationships with aprepitant as well as therapeutic drug monitoring of aprepitant. (C) 2008 Elsevier B.V. All rights reserved.
This Series presents selected papers from the ITU Kaleidoscope Academic Conference that convened in Kyoto, Japan from the 22nd to 24th of April 2013. The topic of the conference was 'Building Sustainable Communiti...
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This Series presents selected papers from the ITU Kaleidoscope Academic Conference that convened in Kyoto, Japan from the 22nd to 24th of April 2013. The topic of the conference was 'Building Sustainable Communities,' in recognition of the challenges that Japan is facing after the Great East Earthquake. The hosts were the Ministry of Internal Affairs and Communication (MIC) of Japan and Kyoto University. Kyoto University is the second oldest Japanese national university after the University of Tokyo. It was founded in 1897 following the Meiji Restoration, which adopted various western systems to build a modern state. [ABSTRACT FROM AUTHOR]
The oxidation reactions of the unsaturated anion [Re3(µ-H)4(CO)10]- with C7H7+ are described. They imply, as the first step, abstraction of a H- ligand, and when performed in the presence of donor species L, such...
The oxidation reactions of the unsaturated anion [Re3(µ-H)4(CO)10]- with C7H7+ are described. They imply, as the first step, abstraction of a H- ligand, and when performed in the presence of donor species L, such as CO or RCN, they lead to the neutral derivatives Re3(µ-H)3(CO)10L2. In the absence of donor molecules, in inert solvents, the new species Re3H2(CO)10(·5-C7H9) is readily obtained in high yields. It has been investigated by single-crystal X-ray analysis. The crystals are monoclinic, space group C2/c, with cell constants a = 31.507 (7) Å, b = 8.561 (3) Å, c = 16.503 (4) Å, β = 106.60 (2)°, and Z = 8. The structure was solved by Patterson and Fourier methods and refined by least-squares techniques, on the basis of 2677 significant independent counter data, up to a final R value of 0.027. The molecule contains a triangular arrangement of rhenium atoms. Two metals, Re2 and Re3, each bear four terminal CO groups, while Re1 is linked to two such ligands and to the ·5-cycloheptadienyl ligand. The two hydrides have been indirectly located, one double-bridging the Re2-Re3 edge and the second one in a triple-bridging location. Rhenium-rhenium bond lengths are Re1-Re2 = 3.160 (1) Å, Re1-Re3 = 3.193 (1) Å, and Re2-Re3 = 3.076 (1) Å. 1H and 13C NMR analyses at different temperatures indicate a fluxional behavior in solution of the C7H9group, involving also the scrambling of the two CO groups bound to Re1. The apparent symmetry for the whole compound at room temperature has been interpreted as deriving from a complete interchange of the coordination sites of the ligands bound to Re1, accompanied by a concerted up and down movement of the µ3-ligand through the Re3 plane. At-100 °C the 10 CO groups and all the hy
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