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Due to the special electronic structure of the rare earth elements, rare earth materials are widely used in optical, electrical, magnetic, ray shielding areas. Nanocrystalline rare earth materials exhibit many of the features, such as the effect of small size, high specific surface area effects, quantum effects, strong light, electricity, magnetic properties, superconductivity, high chemical activity, can greatly improve the performance of the material and function, so the preparation of nano rare earth materials more and more attention. The experiment uses three methods of preparation of nanometer rare earth oxides. Method one using ammonia as the precipitating agent, ammonia water was added dropwise to the solution of rare earth chlorides to prepare a suspension, after dilution is then spray-dried to prepare a finely divided rare earth precursor, and then through the high-temperature calcination, prepared with different nanoscale rare earth compounds; second method is a method obtained in the suspension after several centrifugation after washing with deionized water dispersion to a certain concentration, and then spray-dried and high-temperature calcination, preparation of different nanoscale Rare earth compounds; Method three is the salt of the auxiliary spray drying method, with sodium hydroxide instead of ammonia as the precipitating agent, and other steps and methods of a same. Nanometer rare earth oxides and nitrile rubber blends, Nano Rare Earth / rubber composite material can be obtained. Hot weightlessness (TGA) Ⅹ-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Ⅹ-ray machines and other characterized the nanocrystalline rare earth compounds and Nano Rare Earth / rubber composites. The results are as follows: (1) Preparation of nano Gd2O3: rare earth Gd precursor after calcination at 900 ℃ can be irregular cubic Gd2O3 size about 100nm; using methods can then calcined at 900 ℃ flaky monoclinic Gd2O3, a thickness of less than 100nm; Method III, i.e. salt-assisted spray-drying method, after the washing with water in the 700 ° C calcined product can be obtained flaky monoclinic - Gd2O3 thickness In about 20nm. (2) granules of rare earths La, Ce, Sm a nano inorganic salts: a rare earth element La precursor at 950 ° C the calcination product is tetragonal oxychloride lanthanum was coils, of a thickness of about 200nm; of Ce precursor can be obtained at 700 ℃ calcined irregular cubic crystal of CeO2 particle size of about 100nm; rare earth Sm in the precursor at 950 ℃ calcined product is cubic crystal and a monoclinic mixed Sm2O3 , particle size 100nm. Method three, i.e. salt-assisted spray drying method, the precursor of the rare earth element La in the calcined product was 700 ℃ for tetragonal oxychloride lanthanum, particles are flaky, the thickness of the sheet is less than 50nm; precursor of Ce in 700 ° C the calcination product is a cubic crystal of CeO2 particles were spherical, the diameter of the particles is less than 20nm; for the tetragonal SmOCl monoclinic type Sm2O3-rare earth Sm in the precursor at 700 ° C the calcination product, the particles were flake, the thickness of the sheet is less than 50 nm. Prepared by method (3) Sm / Gd complex oxide was prepared: The experiment used a Sm / Gd composite oxide particle size is about 100nm. The analysis concluded that only in the final product in the same crystal type Gd2O3 and Sm2O3 to form between the two rare earth complex oxides. (4) the nano Gd2O3/NBR composites: a simple blending method uses the method prepared of Gd2O3 and nitrile rubber blends, a vulcanization system got composites of the Gd2O3/NBR, the particle diameter in this composite material Gd2O3 mediated between 100-500nm. Salt assisted spray drying method using latex flocculation prepared Gd2O3 and nitrile rubber and a composite material, Gd2O3 was patchy distribution, uniform dispersion, and the thickness of the sheet is approximately 20nm, but add the increase in the number of copies, the gradual emergence reunion phenomenon. Compared with the weight percent of the same filler content micron Gd2O3/NBR composite materials, the tensile strength of the the nanometer Gd2O3/NBR composite material with a great degree of improvement. In the Top tube voltage 120KVp, compared with the same filler content the micron Gd2O3/NBR composites, the the nanometer Gd2O3/NBR composite material X-ray shielding performance but also about a 15% increase.
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