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971.
972.
S. IshratK. Maaz Rong ChenSoo Hyun Kim M.H. JungGil-Ho Kim 《Current Applied Physics》2012,12(1):65-68
Magnetic nanostructures of nickel embedded in gold were successfully fabricated by electrochemical deposition in porous alumina templates. Structural characterization of the samples confirmed the formation of pure phase, crystalline multi-segmented Au-Ni-Au nanowires. Magnetic characterization of the wires reveals that ferromagnetism arises as a result of Ni embedded in Au segments. An interesting behavior of coercivity was observed that showed a rapid decrease of coercivity for smaller Ni segments while a monotonic decrease was found for the larger segments. Finally, the saturation magnetization of the wires exhibited a slower increase for smaller Ni segments while a sharp increase was observed for larger Ni segments. 相似文献
973.
Enhanced Catalytic Activity in Liquid‐Exfoliated FeOCl Nanosheets as a Fenton‐Like Catalyst
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Jian Zhang Prof. Xiu‐Ling Jiao Dr. Yu‐Guo Xia Fang‐Fang Liu Ying‐Ping Pang Xin‐Fu Zhao Prof. Dai‐Rong Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(27):9321-9329
A facile liquid‐phase exfoliation method to prepare few‐layer FeOCl nanosheets in acetonitrile by ultrasonication is reported. The detailed exfoliation mechanism and generated products were investigated by combining first‐principle calculations and experimental approaches. The similar cleavage energies of FeOCl (340 mJ m?2) and graphite (320 mJ m?2) confirm the experimental exfoliation feasibility. As a Fenton reagent, FeOCl nanosheets showed outstanding properties in the catalytic degradation of phenol in water at room temperature, under neutral pH conditions, and with sunlight irradiation. Apart from the increased surface area of the nanosheets, the surface state change of the nanosheets also plays a key role in improving the catalytic performance. The changes of charge density, density of states (DOS), and valence state of Fe atoms in the exfoliated FeOCl nanosheets versus plates illustrated that surface atomistic relationships made the few‐layer nanosheets higher activity, indicating the exfoliation process of the FeOCl nanosheets also brought about surface state changes. 相似文献
974.
Bin Liu Rong Zhang Zili Xie XiangQian Xiu Liang Li Jieying Kong Huiqiang Yu Pin Han Shulin Gu Yi Shi Zheng YouDou Tang ChenGuang Chen YongHai Wang ZhanGuo 《中国科学G辑(英文版)》2008,51(3):237-242
InN films grown on sapphire at different substrate temperatures from 550°C to 700°C by metalorganic chemical vapor deposition
were investigated. The low-temperature GaN nucleation layer with high-temperature annealing (1100°C) was used as a buffer
for main InN layer growth. X-ray diffraction and Raman scattering measurements reveal that the quality of InN films can be
improved by increasing the growth temperature to 600°C. Further high substrate temperatures may promote the thermal decomposition
of InN films and result in poor crystallinity and surface morphology. The photoluminescence and Hall measurements were employed
to characterize the optical and electrical properties of InN films, which also indicates strong growth temperature dependence.
The InN films grown at temperature of 600°C show not only a high mobility with low carrier concentration, but also a strong
infrared emission band located around 0.7 eV. For a 600 nm thick InN film grown at 600°C, the Hall mobility achieves up to
938 cm2/Vs with electron concentration of 3.9 × 1018 cm−3.
Supported by the National Basic Research Program of China (Grant No. 2006CB6049), the National Natural Science Foundation
of China (Grant Nos. 6039072, 60476030 and 60421003), the Great Fund of the Ministry of Education of China (Grant No. 10416),
the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20050284004), and the Natural
Science Foundation of Jiangsu Province of China (Grant Nos. BK2005210 and BK2006126) 相似文献
975.
976.
PSD性能是评价电子储存环真空室材料及材料表面处理优劣的一个重要指标.对一约1.5m长不锈钢管道真空室进行了镀TiN薄膜处理,并在合肥光源机器研究用光束线(MSB)的PSD实验站上对该真空室在镀TiN薄膜处理前后分别进行了PSD性能测试实验研究.测试研究结果表明,TiN薄膜处理对于减小不锈钢材料PSD有非常明显的作用. 相似文献
977.
Xiaochun Rong 《Geometriae Dedicata》2002,95(1):157-182
The symmetry rank of a Riemannian manifold is the rank of the isometry group. We determine precisely which closed simply connected 5-manifolds admit positively curved metrics with (almost maximal) symmetry rank two. We also determine the precise Euler characteristic and the fundamental groups of all closed positively curved n-manifolds with almost maximal symmetry rank [(n–1)/2] (n 6, 7). 相似文献
978.
Aubert B Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Palano A Pompili A Chen GP Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Clark AR Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kral JF LeClerc C Levi ME Lynch G Oddone PJ Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Harrison TJ Hawkes CM Knowles DJ O'Neale SW Penny RC Watson AT 《Physical review letters》2002,88(22):221802
Flavor oscillations of neutral B mesons have been studied in e+e- annihilation data collected with the BABAR detector at center-of-mass energies near the upsilon(4S) resonance. The data sample used for this purpose consists of events in which one B0 meson is reconstructed in a hadronic decay mode, while the flavor of the recoiling B0 is determined with a tagging algorithm that exploits the correlation between the flavor of the heavy quark and the charges of its decay products. From the time development of the observed mixed and unmixed final states, we determine the B0-B-0 oscillation frequency deltamd to be 0.516+/-0.016(stat)+/-0.010(syst) ps-1. 相似文献
979.
Aubert B Boutigny D Gaillard JM Hicheur A Karyotakis Y Lees JP Robbe P Tisserand V Palano A Chen GP Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Reinertsen PL Stugu B Abbott B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Clark AR Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kluth S Kolomensky YG Kral JF LeClerc C Levi ME Liu T Lynch G Meyer AB Momayezi M Oddone PJ Perazzo A Pripstein M Roe NA Romosan A Ronan MT Shelkov VG Telnov AV Wenzel WA Zisman MS 《Physical review letters》2002,88(10):101805
The branching fractions of the exclusive decays B0-->K(*0)gamma and B+-->K(*+)gamma are measured from a sample of (22.74+/-0.36)x10(6) BB decays collected with the BABAR detector at the PEP-II asymmetric e(+)e(-) collider. We find B (B0-->K(*0)gamma) = [4.23+/-0.40(stat)+/-0.22(syst)]x10(-5), B(B+-->K(*+)gamma) = [3.83+/-0.62(stat)+/-0.22(syst)]x10(-5) and constrain the CP-violating charge asymmetry to be -0.170K(*)gamma)<0.082 at 90% C.L. 相似文献
980.
一类带干扰风险模型的推广 总被引:6,自引:0,他引:6
In this paper, the cLassicaL risk process perturbed by diffusion is genera]ized by alLowing for “size fluctuation“ and the rtl[n probabiLity for this new model is dlscussed. 相似文献