The hybrid particles composed of hydroxyapatite （HAp） and ferrite （ γ-Fe203） were synthesized by two-step precipitation method. The effect of reaction temperature on the morphology of the hybrids was also studied...The hybrid particles composed of hydroxyapatite （HAp） and ferrite （ γ-Fe203） were synthesized by two-step precipitation method. The effect of reaction temperature on the morphology of the hybrids was also studied. The resultant hybrids were characterized by transmission electron microscopy （TEM） and X-ray diffraction analysis（XRD）. It was found that γ-Fe203 nanoparticles dispersed within the HAp matrix and these hybrids had a feather-like or spherical morphology when synthesized at 90 ℃ or room temperature, respectively. The magnetic properties of the hybrid showed good superparamagnetic feature, and they could be controlled by the external magnetic field.展开更多
Fe-N thin films were fabricated on both 100Si and NaCl substrates by RF magnetron sputtering under low nitrogen partial pressure. The microstructure and magnetic properties of Fe-N thin films were investigated with th...Fe-N thin films were fabricated on both 100Si and NaCl substrates by RF magnetron sputtering under low nitrogen partial pressure. The microstructure and magnetic properties of Fe-N thin films were investigated with the increase of the substrate temperature （Ts） and the annealing temperature （Ta）. It is more difficult for nitrogen atoms to enter the Fe lattice under higher Ts above 150℃. The phase evolution is visible at higher Ta above 200℃. The phase transformation of α＇＇-Fe16N2 occurred at 400℃. The change of crystal size with Ta was clearly visible from bright and dark field images. The clear high-resolution electron microscope （HREM） images of 110α, 111γ＇, 112α＇＇, and 200α＇＇ phases were observed. The interplanar distances from TEM （transmission electron microscope） and HREM match the calculated values very well. From the results of the vibrating sample magnetometer （VSM）, the good magnetic properties of Fe-N films were obtained at 150℃ of Ts and 200℃ of Ta, respectively.展开更多
In this work, pure α-Fe2O3 and Er2O3-Fe2O3 nanotubes were synthesized by a simple single-capillary electrospin- ning technology followed by calcination treatment. The morphologies and crystal structures of the as-pre...In this work, pure α-Fe2O3 and Er2O3-Fe2O3 nanotubes were synthesized by a simple single-capillary electrospin- ning technology followed by calcination treatment. The morphologies and crystal structures of the as-prepared samples were characterized by scanning electron microscopy and x-ray diffraction, respectively. The gas-sensing properties of the as-prepared samples have been researched, and the result shows that the Er2O3-Fe2O3 nanotubes exhibit much better sen- sitivity to ethanol. The response value of Er2O3-Fe2O3 nanotubes to 10 ppm ethanol is 21 at the operating temperature 240α, which is 14 times larger than that of pure α-Fe2O3 nanotubes （response value is 1.5）. The ethanol sensing properties of α-Fe2O3 nanotubes are remarkably enhanced by doping Er, and the lowest detection limit of Er2O3-Fe2O3 nanotubes is 300 ppb, to which the response value is about 2. The response and recovery times are about 4 s and 70 s to 10 ppm ethanol, respectively. In addition, the Er2O3-Fe2O3 nanotubes possess good selectivity and long-term stability.展开更多
Iron oxide nanoparticles are the most popular magnetic nanoparticles used in biomedical applications due to their low cost, low toxicity, and unique magnetic property. Magnetic iron oxide nanoparticles, including magn...Iron oxide nanoparticles are the most popular magnetic nanoparticles used in biomedical applications due to their low cost, low toxicity, and unique magnetic property. Magnetic iron oxide nanoparticles, including magnetite （Fe304） and maghemite （γ-Fe203）, usually exhibit a superparamagnetic property as their size goes smaller than 20 nm, which are often denoted as superparamagnetic iron oxide nanoparticles （SPIONs） and utilized for drug delivery, diagnosis, therapy, and etc. This review article gives a brief introduction on magnetic iron oxide nanoparticles in terms of their fundamentals of magnetism, magnetic resonance imaging （MRI）, and drug delivery, as well as the synthesis approaches, surface coating, and application examples from recent key literatures. Because the quality and surface chemistry play important roles in biomedical applications, our review focuses on the synthesis approaches and surface modifications of iron oxide nanopar- ticles. We aim to provide a detailed introduction to readers who are new to this field, helping them to choose suitable synthesis methods and to optimize the surface chemistry of iron oxide nanoparticles for their interests.展开更多
ZnO and In203 films were prepared by thermal oxidation of vacuum deposited zinc and indium films, respec- tively onto the glass substrate at 30 ℃. The fabricated films have been irradiated with 100-MeV Ni7＋ ions at ...ZnO and In203 films were prepared by thermal oxidation of vacuum deposited zinc and indium films, respec- tively onto the glass substrate at 30 ℃. The fabricated films have been irradiated with 100-MeV Ni7＋ ions at different fluences ranging from 5×1011 to 5×1013 ions/cm2. The structural and gas sensing properties of pristine and irradiated films have been discussed. X-ray diffraction （XRD） pattern of pristine and irradiated films reveal that the films are polycrystalline in nature and crystallinity increases after irradiation. In this study, highly porous In203 nanorods evolved when being irradiated at a fluence of 5×1013 ions/cm2 while ZnO film shows decrease in number of nanowires. The ammonia sensing performance of the Ni^7＋ irradiated In203 films shows an improvement as compared to its pristine counterpart.展开更多
Though the structure of α"-Fe<sub>16</sub>N<sub>2</sub> was well known, the great interest in Fe<sub>16</sub>N<sub>2</sub> arose from its giant saturation magnetic...Though the structure of α"-Fe<sub>16</sub>N<sub>2</sub> was well known, the great interest in Fe<sub>16</sub>N<sub>2</sub> arose from its giant saturation magnetic flux density which was found to be 2.58T at room temperature. The research work on preparing Fe<sub>16</sub>N<sub>2</sub> in high abundance is active on both bulk materials and thin film form. However, up to now, only Sugita and his coworkers have successfully prepared Fe<sub>16</sub>N<sub>2</sub> single-crystal films on semiconductor substrates because of its metastable property. They manifested that the M<sub>s</sub> was up to 2.9 T at展开更多
Cu and Cu/ITO films were prepared on polyethylene terephthalate （PET） substrates with a Ga2O3 buffer layer using radio frequency （RF） and direct current （DC） magnetron sputtering. The effect of Cu layer thicknes...Cu and Cu/ITO films were prepared on polyethylene terephthalate （PET） substrates with a Ga2O3 buffer layer using radio frequency （RF） and direct current （DC） magnetron sputtering. The effect of Cu layer thickness on the optical and electrical properties of the Cu film deposited on a PET substrate with a Ga2O3 buffer layer was studied, and an appropriate Cu layer thickness of 4.2 nm was obtained. Changes in the optoelectrical properties of Cu（4.2 nm）/ITO（30 nm） films were investigated with respect to the Ga2O3 buffer layer thickness. The optical and electrical properties of the Cu/ITO films were significantly influenced by the thickness of the Ga2O3 buffer layer. A maximum transmission of 86%, sheet resistance of 45 Ω/□ and figure of merit of 3.96 × 10^-3 Ω^ -1 were achieved for Cu（4.2 nm）/ITO（30 nm） films with a Ga2O3 layer thickness of 15 nm.展开更多
基金Funded by the Project of Shandong Province Higher Educational Science and Technology Program(No.J09LC13)the Promotive Research Fund for Excellent Young and Middle-Aged Scientists of the Shandong Province(No.BS2010CL018)
文摘The hybrid particles composed of hydroxyapatite （HAp） and ferrite （ γ-Fe203） were synthesized by two-step precipitation method. The effect of reaction temperature on the morphology of the hybrids was also studied. The resultant hybrids were characterized by transmission electron microscopy （TEM） and X-ray diffraction analysis（XRD）. It was found that γ-Fe203 nanoparticles dispersed within the HAp matrix and these hybrids had a feather-like or spherical morphology when synthesized at 90 ℃ or room temperature, respectively. The magnetic properties of the hybrid showed good superparamagnetic feature, and they could be controlled by the external magnetic field.
基金supported by the National Natural Science Foundation of China(No.50674071)Tianjin Natural Science Foundation of China(No.06YFJZJC01300)+1 种基金the Program for New Century Excellent Talents in University(NCET-06-0245)the Platform Project of Tianjin for Innovation in Science and Technology and Environmental Construction(No.06TXTJJC13900).
文摘Fe-N thin films were fabricated on both 100Si and NaCl substrates by RF magnetron sputtering under low nitrogen partial pressure. The microstructure and magnetic properties of Fe-N thin films were investigated with the increase of the substrate temperature （Ts） and the annealing temperature （Ta）. It is more difficult for nitrogen atoms to enter the Fe lattice under higher Ts above 150℃. The phase evolution is visible at higher Ta above 200℃. The phase transformation of α＇＇-Fe16N2 occurred at 400℃. The change of crystal size with Ta was clearly visible from bright and dark field images. The clear high-resolution electron microscope （HREM） images of 110α, 111γ＇, 112α＇＇, and 200α＇＇ phases were observed. The interplanar distances from TEM （transmission electron microscope） and HREM match the calculated values very well. From the results of the vibrating sample magnetometer （VSM）, the good magnetic properties of Fe-N films were obtained at 150℃ of Ts and 200℃ of Ta, respectively.
基金supported by Jilin Provincial Science and Technology Department,China(Grant No.20140204027GX)the Challenge Cup for College Students,China(Grant No.450060497053)
文摘In this work, pure α-Fe2O3 and Er2O3-Fe2O3 nanotubes were synthesized by a simple single-capillary electrospin- ning technology followed by calcination treatment. The morphologies and crystal structures of the as-prepared samples were characterized by scanning electron microscopy and x-ray diffraction, respectively. The gas-sensing properties of the as-prepared samples have been researched, and the result shows that the Er2O3-Fe2O3 nanotubes exhibit much better sen- sitivity to ethanol. The response value of Er2O3-Fe2O3 nanotubes to 10 ppm ethanol is 21 at the operating temperature 240α, which is 14 times larger than that of pure α-Fe2O3 nanotubes （response value is 1.5）. The ethanol sensing properties of α-Fe2O3 nanotubes are remarkably enhanced by doping Er, and the lowest detection limit of Er2O3-Fe2O3 nanotubes is 300 ppb, to which the response value is about 2. The response and recovery times are about 4 s and 70 s to 10 ppm ethanol, respectively. In addition, the Er2O3-Fe2O3 nanotubes possess good selectivity and long-term stability.
基金Project supported by Start-up Grant of Nanyang Technological UniversityTier 1 Grant of Ministry of Education,Singapore(RGT8/13)
文摘Iron oxide nanoparticles are the most popular magnetic nanoparticles used in biomedical applications due to their low cost, low toxicity, and unique magnetic property. Magnetic iron oxide nanoparticles, including magnetite （Fe304） and maghemite （γ-Fe203）, usually exhibit a superparamagnetic property as their size goes smaller than 20 nm, which are often denoted as superparamagnetic iron oxide nanoparticles （SPIONs） and utilized for drug delivery, diagnosis, therapy, and etc. This review article gives a brief introduction on magnetic iron oxide nanoparticles in terms of their fundamentals of magnetism, magnetic resonance imaging （MRI）, and drug delivery, as well as the synthesis approaches, surface coating, and application examples from recent key literatures. Because the quality and surface chemistry play important roles in biomedical applications, our review focuses on the synthesis approaches and surface modifications of iron oxide nanopar- ticles. We aim to provide a detailed introduction to readers who are new to this field, helping them to choose suitable synthesis methods and to optimize the surface chemistry of iron oxide nanoparticles for their interests.
文摘ZnO and In203 films were prepared by thermal oxidation of vacuum deposited zinc and indium films, respec- tively onto the glass substrate at 30 ℃. The fabricated films have been irradiated with 100-MeV Ni7＋ ions at different fluences ranging from 5×1011 to 5×1013 ions/cm2. The structural and gas sensing properties of pristine and irradiated films have been discussed. X-ray diffraction （XRD） pattern of pristine and irradiated films reveal that the films are polycrystalline in nature and crystallinity increases after irradiation. In this study, highly porous In203 nanorods evolved when being irradiated at a fluence of 5×1013 ions/cm2 while ZnO film shows decrease in number of nanowires. The ammonia sensing performance of the Ni^7＋ irradiated In203 films shows an improvement as compared to its pristine counterpart.
基金the National Natural Science Foundation of China.
文摘Though the structure of α"-Fe<sub>16</sub>N<sub>2</sub> was well known, the great interest in Fe<sub>16</sub>N<sub>2</sub> arose from its giant saturation magnetic flux density which was found to be 2.58T at room temperature. The research work on preparing Fe<sub>16</sub>N<sub>2</sub> in high abundance is active on both bulk materials and thin film form. However, up to now, only Sugita and his coworkers have successfully prepared Fe<sub>16</sub>N<sub>2</sub> single-crystal films on semiconductor substrates because of its metastable property. They manifested that the M<sub>s</sub> was up to 2.9 T at
基金supported by the National Natural Science Foundation of China(No.10974077)the National Science Foundation of Shandong Province,China(No.2009ZRB01702)the Shandong Province Higher Educational Science and Technology Program,China(No.J10LA08)
文摘Cu and Cu/ITO films were prepared on polyethylene terephthalate （PET） substrates with a Ga2O3 buffer layer using radio frequency （RF） and direct current （DC） magnetron sputtering. The effect of Cu layer thickness on the optical and electrical properties of the Cu film deposited on a PET substrate with a Ga2O3 buffer layer was studied, and an appropriate Cu layer thickness of 4.2 nm was obtained. Changes in the optoelectrical properties of Cu（4.2 nm）/ITO（30 nm） films were investigated with respect to the Ga2O3 buffer layer thickness. The optical and electrical properties of the Cu/ITO films were significantly influenced by the thickness of the Ga2O3 buffer layer. A maximum transmission of 86%, sheet resistance of 45 Ω/□ and figure of merit of 3.96 × 10^-3 Ω^ -1 were achieved for Cu（4.2 nm）/ITO（30 nm） films with a Ga2O3 layer thickness of 15 nm.
