Dissolution of functional materials and rare earth oxides into pseudo alveolar fluid.

نویسندگان

  • Mitsutoshi Takaya
  • Yasushi Shinohara
  • Fumio Serita
  • Mariko Ono-Ogasawara
  • Noriko Otaki
  • Tadao Toya
  • Ayako Takata
  • Katsumi Yoshida
  • Norihiko Kohyama
چکیده

The dissolution rates of rare earth oxides and two types of rare earth containing functional materials into water, saline solution, and Gamble's fluid were measured in order to evaluate the biological effects of rare earth-containing functional materials. The tested materials were yttrium, lanthanum, cerium and neodymium oxides, and neodymium-boron-iron magnet alloy (NdBFe) and lanthanum-mish-metal-nickel-cobalt (LmNiCo) hydrogen-containing alloy. The dissolution rates of the rare earth oxides were very low, resulting in concentrations of rare earth elements in the test solutions of the order of ppb. In the most extreme case, Gamble's fluid dissolved 1,400 times more of the rare earth oxides than pure water. Fairly high concentration of neodymium were found in the dissolving fluids, which means that trace neodymium present as an impurity in each rare earth oxide dissolved preferentially. For yttrium oxide, the ratio of neodymium to yttrium that dissolved in the saline solution was greater than 78,000 to 1, taking into account the amount of each that was originally present in the yttrium oxide.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Determination of Rare Earth Elements in Products of Chadormalu Iron Ore Concentrator Plant (Iran) from Beneficiation Point of View

Different samples have been prepared from different products in Chadormalu iron ore concentrator plant: Low intensity magnetite separators concentrate (magnetite concentrate), reverse flotation tail (final hematite concentrate), flotation concentrate (apatite concentrate), final tail (L.I.M.S. tail + reverse flotation concentrate+ apatite flotation tail). The samples were used for rare eart...

متن کامل

Mechanical activation of phosphate concentrates to enhance dissolution efficiency of rare earth elements from a kinetic viewpoint

The Esfordi phosphate concentrate mainly contains fluorapatite, monazite, and xenotime as rare earth element (REE) minerals, accounting for 1.5% of rare earth metals. The monazite and xenotime minerals are refractory and their decomposition is only possible at high temperatures. Thus mechanical activation was used in the present work for this purpose. After 90 minutes of mechanical activation, ...

متن کامل

Cytotoxicity of the rare earth metals cerium, lanthanum, and neodymium in vitro: comparisons with cadmium in a pulmonary macrophage primary culture system.

The rare earth metals cerium, lanthanum, and neodymium each were evaluated in an in vitro cytotoxicity assay system using adult, male Sprague-Dawley rat pulmonary alveolar macrophages. Both the soluble chloride form of these metals and their insoluble metal oxides were studied. For comparison purposes, the cytotoxicities of cadmium chloride and cadmium oxide were also quantified in this test sy...

متن کامل

Electrochemical Synthesis of Rare Earth Ceramic Oxide Coatings

Rare earth ceramic oxides are used in several applications including, phosphors, gas sensors, fuel cells, catalytic converters, and corrosion protection. These materials exhibit attractive properties such as fracture toughness, stiffness, and high strengthto-weight ratios. Synthesis of rare earth oxides includes a long list of techniques, but electrodeposition is one that has not been used as e...

متن کامل

Dielectric constants of binary rare-earth compounds

The dielectric constants of rare-earth oxides (RE2O3) and rare-earth nitrides, phosphides, arsenides, and antimonides (REX, RE = rare-earth element, X = N, P, As, Sb) are quantitatively estimated. The estimation is based on the approximately linear relationship between the dielectric constant and the atomic number of the constituent atoms. Similar correlations are valid in nearly all series of ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Industrial health

دوره 44 4  شماره 

صفحات  -

تاریخ انتشار 2006