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1.
I. Ortalli G. Pedrazzi K. Jiang X. Zhang C. Carlo-Stella V. Rizzoli 《Il Nuovo Cimento D》1992,14(4):351-358
Summary A new approach to cancer treatment using low-energy gamma-rays is discussed. Cultures of bone marrow mononuclear cells collected
from normal donors and patients with chronic myelogenous leukaemia have been studied after the addition of hematin, at different
concentrations, and irradiation by a M?ssbauer gamma-ray source. Growth stimulation has been observed when hematin is added
to normal bone marrow cultures, while growth inhibition is observed when hematin is added to leukaemic cultures. The effect
becomes then more pronounced when hematin is used in combination with M?ssbauer gamma-rays. 相似文献
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Oxyhemoglobin from human normal adults and from leukaemic patients has been studied by Mössbauer spectroscopy to investigate the possibility to distinguish, through differences in the Fe2+ electronic structure, normals and leukaemic patients. 相似文献
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Transition of the radial electric field by electron cyclotron heating in the CHS heliotron/torsatron
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Albano VG Di Serio M Monari M Orabona I Panunzi A Ruffo F 《Inorganic chemistry》2002,41(10):2672-2677
The silver-assisted ligand metathesis reaction involving a platinum(II) complex of formula [PtClMe(N,N-chelate)] with acetonitrile has been investigated. By using a suitably hindered N,N-chelate, an otherwise hardly detectable trinuclear species has been isolated and characterized through X-ray diffractometry. The trinuclear cation consists of two nearly orthogonal [PtCl(Me)(N,N-chelate)] square-planar units entrapping an Ag(+) cation through the chloride ligands that, acting as bidentate, form a linear AgCl(2) unit with two nonequivalent Ag-Cl bonds. The residual acidity of the silver cation is satisfied by one secondary Ag-Pt interaction [Ag-Pt(1) = 2.82 A] in which the platinum atom acts as a donor. Kinetic studies have demonstrated that the silver assistance operates both through a simple associative step and through a pathway in which the above trinuclear complex is an active intermediate. In a noncoordinating solvent the latter species evolves with AgCl loss and formation of a dinuclear Pt,Pt complex showing a rare single chloride bridge. 相似文献
10.
Four different types of amine-attached MCM-48 silicas were prepared and investigated for CO(2) separation from N(2). Monomeric and polymeric hindered and unhindered amines were attached to the pore surface of the MCM-48 silica and characterized with respect to their CO(2) sorption properties. The pore structures and amino group content in these modified silicas were investigated by XRD, FT-IR, TGA, N(2) adsorption/desorption at 77 K and CHN/Si analysis, which confirmed that in all cases the amino groups were attached to the pore surface of MCM-48 at 1.5-5.2 mmol/g. The N(2) adsorption/desorption analysis showed a considerable decrease of the pore volume and surface area for the MCM-48 silica containing a polymeric amine (e.g., polyethyleneimine). The CO(2) adsorption rates and capacities of the amine-attached MCM-48 samples were studied employing a sorption microbalance. The results obtained indicated that in addition to the concentration of surface-attached amino groups, specific interactions between CO(2) and the surface amino groups, and the resultant pore structure after amine group attachment have a significant impact on CO(2) adsorption properties of these promising adsorbent materials. 相似文献