AlCl(3) solution was analyzed at concentrations from 0.02 to 100 mM using an electrospray ionization quadrupole mass spectrometer (ESI-Q-MS), and the dissolution state of aluminum ions is discussed. Results obtained using ESI-Q-MS were consistent with those obtained using (27)Al nuclear magnetic resonance ((27)Al NMR). Aluminum species existed mainly as positively charged monomeric aluminum hydroxide coordinated with several water molecules in solution. The complexation of chloride ions by aluminum ions differed between the positive and negative ion modes. Chemical reactions that partially modified chemical forms of species through ESI-Q-MS measurement were also observed. In the same aluminum chloride solution, using ESI-TOF-MS and ESI-Q-MS/MS studies, the disagreement of the reports is discussed. It is concluded that ESI-TOF-MS might show also the gas-phase reaction in the mass spectrometer but the dissolution state of aluminum species can be shown by ESI-Q-MS.
To obtain current data of lanthanoides and heavy metals in Sagami Bay sediment, a sediment sample was collected at a location 13 km off shore. The surface sediment (0 1 cm) was decomposed with HNO3, HF and HClO4. The detection of these elements was achieved by inductively coupled plasma mass spectrometry. These data will be used as a comprehensive baseline data for future environmental-impact studies, such as on the discharge of accumulated sands and sediments from the dam in Sagami River. A sediment reference material, MESS-3, was also analyzed to verify the present analytical method. The obtained value for heavy metals, such as Cr and As, were in good agreement with the certified values. The concentrations of lanthanoides in MESS-3 were also presented.
Manganese nodules, which are mainly composed of manganese and iron oxide, show the structure of annual rings. Chemical compositions vary widely, such as the concentrations of Co, Ni and Cu, and the relative ratio of Mn/Fe. It may be possible to analyze the old environmental changes from the chemical composition. In this study, characterization of the chemical composition of manganese nodules was performed to find the factors concerning the effect of a changing of environment. In the sample, a characteristic layer was found in a raster image of X-rays by SEM-EDX. In this layer, the abundances of iron and sulfur were high, but manganese was low. In this particular structure, pyrite should be considered to occur as very small particles. Further, manganese nodules were examined along the structure of annual rings in more detail for chemical composition, which confirmed the result of SEM-EDX. The main elements were analyzed by an inductively coupled plasma atomic emission spectrometer (ICP-AES), and trace elements were analyzed by an inductively coupled plasma mass spectrometer (ICP-MS). As a result, the distribution of the elements changed to 1/3 from 1/2 and 3/4 from the center. The distribution of the elements changed one after another at the former. The latter agreed with the section at which there was sulfur when analyzed by SEM-EDX. The distribution of the elements suddenly changed at the same time at the latter. Therefore, we can guess that the different changes of the environment occurred twice.
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