Ammonia （NH3） has an important use in the chemical industry and is widely found in industrial wastewater. For this investigation of copper-based rare earth composite metal materials, aqueous solutions containing 400...Ammonia （NH3） has an important use in the chemical industry and is widely found in industrial wastewater. For this investigation of copper-based rare earth composite metal materials, aqueous solutions containing 400 mg/L of ammonia were oxidized in a batch-bed reac-tor with a catalyst prepared by the co-precipitation of copper nitrate, lanthanum nitrate and cerium nitrate. Barely any of the dissolved ammo-nia was removed by wet oxidation without a catalyst, but about 88% of the ammonia was reduced during wet oxidation over the catalysts at 423 K with an oxygen partial pressure of 4.0 MPa. The catalytic redox behavior was determined by cyclic voltammetry （CV）. Furthermore, the catalysts were characterized using thermogravimetric analyzer （TGA） and scanning electron microscope-energy dispersive X-ray spectroscopy （SEM-EDX）, which showed that the catalytic behavior was related to the metal oxide properties of the catalyst. In addition, the copper-lanthanum-cerium composite-induced cytotoxicity in the human lung MRC-5 cell line was tested, and the percentage cell survival was determined by 3-（4,5-dimethylthiazol-2-yl）-5-（3-carboxymethoxyphenyl）-2-（4-sulfophenyl）-2H-tetra-zolium （MTS） analysis in vitro. No ap-parent cytotoxicity was observed when the human lung cells were exposed to the copper-lanthanum-cerium composite.展开更多
利用恒电位仪、等离子发射光谱仪、电子能谱仪、X射线衍射仪、透射电子显微镜等考察和分析了引入稀土金属La时化学镀Co Fe B合金的阴极极化曲线、沉积速度、化学成分和晶体结构。结果表明 ,稀土La的介入明显改善了化学镀Co Fe B合金的...利用恒电位仪、等离子发射光谱仪、电子能谱仪、X射线衍射仪、透射电子显微镜等考察和分析了引入稀土金属La时化学镀Co Fe B合金的阴极极化曲线、沉积速度、化学成分和晶体结构。结果表明 ,稀土La的介入明显改善了化学镀Co Fe B合金的静止电位和极化度 ,随镀液里稀土金属La添加量的增加 ,合金的沉积速度和镀层中La的含量都是先增后降 ,且都在La加入 0 6g·L- 1 时达到最大值。稀土La的介入使化学镀Co Fe B La合金镀层中B的含量减少 ,Co和Fe的含量增加 ,并使具有非晶态结构的化学镀Co Fe B合金转化为晶态结构的化学镀Co Fe B La合金。展开更多
Eu3＋ doped La2Ti2O7 nanocrystals with pure monoclinic phase and size of about 100 nm were prepared by a citric acid （CA） assisted sol-gel method. Techniques of thermo-gravimetric （TG） and differential scanning ca...Eu3＋ doped La2Ti2O7 nanocrystals with pure monoclinic phase and size of about 100 nm were prepared by a citric acid （CA） assisted sol-gel method. Techniques of thermo-gravimetric （TG） and differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, as well as transmission electron microscopy （TEM） were employed to characterize the as-synthesized nanoparticles. Furthermore, photoluminescence （PL） performances of the Eu3＋ doped La2Ti2O7 nanocrystals were evaluated with focus on the effects of calcination temperature and Eu3＋ doping concentration on the photoluminescence properties.展开更多
In this paper, a series of Fe- and Co-doped lanthanum（hydr）oxides catalysts were prepared by a simple coprecipitationhydrothermal method. The as-prepared catalysts were characterized with various techniques includin...In this paper, a series of Fe- and Co-doped lanthanum（hydr）oxides catalysts were prepared by a simple coprecipitationhydrothermal method. The as-prepared catalysts were characterized with various techniques including powder X-ray diffraction（XRD）, N2 adsorption/desorption, inductively coupled plasma（ICP） and transmission electron microscopy（TEM）. The Fe-based catalysts exhibited consecutive phase changes of amorphous Fe Ox→FeLaO3→Fe2N under different stages（as-prepared→calcination→ammonia decomposition reaction）; as for Co-based catalysts, the phase transformation followed a sequence of Co（OH）2→Co3O4→metallic Co. It was revealed that Fe2N and metallic Co were most probably the active crystalline phase respectively for Feand Co-based catalysts in the decomposition of ammonia.展开更多
基金supported by the National Science Council of Taiwan (NSC 98-2221-E-132-003-MY3)
文摘Ammonia （NH3） has an important use in the chemical industry and is widely found in industrial wastewater. For this investigation of copper-based rare earth composite metal materials, aqueous solutions containing 400 mg/L of ammonia were oxidized in a batch-bed reac-tor with a catalyst prepared by the co-precipitation of copper nitrate, lanthanum nitrate and cerium nitrate. Barely any of the dissolved ammo-nia was removed by wet oxidation without a catalyst, but about 88% of the ammonia was reduced during wet oxidation over the catalysts at 423 K with an oxygen partial pressure of 4.0 MPa. The catalytic redox behavior was determined by cyclic voltammetry （CV）. Furthermore, the catalysts were characterized using thermogravimetric analyzer （TGA） and scanning electron microscope-energy dispersive X-ray spectroscopy （SEM-EDX）, which showed that the catalytic behavior was related to the metal oxide properties of the catalyst. In addition, the copper-lanthanum-cerium composite-induced cytotoxicity in the human lung MRC-5 cell line was tested, and the percentage cell survival was determined by 3-（4,5-dimethylthiazol-2-yl）-5-（3-carboxymethoxyphenyl）-2-（4-sulfophenyl）-2H-tetra-zolium （MTS） analysis in vitro. No ap-parent cytotoxicity was observed when the human lung cells were exposed to the copper-lanthanum-cerium composite.
文摘利用恒电位仪、等离子发射光谱仪、电子能谱仪、X射线衍射仪、透射电子显微镜等考察和分析了引入稀土金属La时化学镀Co Fe B合金的阴极极化曲线、沉积速度、化学成分和晶体结构。结果表明 ,稀土La的介入明显改善了化学镀Co Fe B合金的静止电位和极化度 ,随镀液里稀土金属La添加量的增加 ,合金的沉积速度和镀层中La的含量都是先增后降 ,且都在La加入 0 6g·L- 1 时达到最大值。稀土La的介入使化学镀Co Fe B La合金镀层中B的含量减少 ,Co和Fe的含量增加 ,并使具有非晶态结构的化学镀Co Fe B合金转化为晶态结构的化学镀Co Fe B La合金。
基金financially supported by the National Natural Science Foundation of China (No.50972166)
文摘Eu3＋ doped La2Ti2O7 nanocrystals with pure monoclinic phase and size of about 100 nm were prepared by a citric acid （CA） assisted sol-gel method. Techniques of thermo-gravimetric （TG） and differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, as well as transmission electron microscopy （TEM） were employed to characterize the as-synthesized nanoparticles. Furthermore, photoluminescence （PL） performances of the Eu3＋ doped La2Ti2O7 nanocrystals were evaluated with focus on the effects of calcination temperature and Eu3＋ doping concentration on the photoluminescence properties.
基金Project supported by the National Natural Science Foundation of China(21301107,21501109)Fundamental Research Funding of Shandong University(2014JC005)+1 种基金the Taishan Scholar Project of Shandong Province(China)Doctoral Funding of Ministry of Education of China(20130131120009)
文摘In this paper, a series of Fe- and Co-doped lanthanum（hydr）oxides catalysts were prepared by a simple coprecipitationhydrothermal method. The as-prepared catalysts were characterized with various techniques including powder X-ray diffraction（XRD）, N2 adsorption/desorption, inductively coupled plasma（ICP） and transmission electron microscopy（TEM）. The Fe-based catalysts exhibited consecutive phase changes of amorphous Fe Ox→FeLaO3→Fe2N under different stages（as-prepared→calcination→ammonia decomposition reaction）; as for Co-based catalysts, the phase transformation followed a sequence of Co（OH）2→Co3O4→metallic Co. It was revealed that Fe2N and metallic Co were most probably the active crystalline phase respectively for Feand Co-based catalysts in the decomposition of ammonia.
基金National Natural Science Foundation of China(21276036)Liaoning Provincial Nature Science Foundation of China(2014025018)the Fundamental Research Funds for the Central Universities(3132014323)
