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111.
液相沉积法制备光催化活性TiO2薄膜和纳米粉体 总被引:7,自引:0,他引:7
采用液相沉积法,在35℃通过向六氟钛酸铵水溶液中添加硼酸和结晶诱导剂锐 铁矿型TiO2纳米晶,沉积出具有光催化活性的Ti02薄膜和纳米粉体.用XRD,AFM, 阶梯仪,UV-vis,BET法对Ti02薄膜和粉体的沉积条件、结构、厚度和性能进行了测 定和表征,并用亚甲兰的降解,评价了TiO2薄膜和纳米粉体的光催化活性.结果表 明,当反应物六氟钛酸铵与硼酸的摩尔比为1:2—1:4时,沉积的粉体和薄膜含有 锐钛矿相Ti02;经300℃热处理的Ti02薄膜和纳米粉体具有最高的光催化活性,它 的光催化活性是未经热处理前的5倍.本文还解释了经300℃热处理的薄膜和纳米粉 体具有最高光催化活性的原因. 相似文献
112.
A. Kankainen L. Batist S. A. Eliseev V. -V. Elomaa T. Eronen U. Hager J. Hakala A. Jokinen I. Moore Yu. N. Novikov H. Penttilä K. Peräjärvi A. V. Popov S. Rahaman S. Rinta-Antila P. Ronkanen A. Saastamoinen D. M. Seliverstov T. Sonoda G. K. Vorobjev J. Äystö 《The European Physical Journal A - Hadrons and Nuclei》2006,29(3):271-280
The masses of 80, 81, 82, 83Y, 83, 84, 85, 86, 88Zr and 85, 86, 87, 88Nb have been measured with a typical precision of 7keV by using the Penning trap setup at IGISOL. The mass of 84Zr has been measured for the first time. These precise mass measurements have improved Sp and QEC values for astrophysically important nuclides. 相似文献
113.
Liu JM Wu RH Li DC Zhou P Zheng MM Zeng XY Liu DX Huang XM Zhu GH 《Journal of fluorescence》2006,16(5):625-630
A new method for the determination of trace mercury by solid substrate-room temperature phosphorimetry (SS-RTP) quenching method has been established. In glycine-HCl buffer solution, xylenol orange (XO) can react with Sn4+ to form the complex [Sn(XO)6]4+. [Sn(XO)6]4+ can interact with Fin− (fluorescein anion) to form the ion associate [Sn(XO)6]4+·[(Fin)4]−, which can emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM). Hg2+ can catalyze H2O2 oxidizing the ion association complex [Sn(XO)6]4+·[(Fin)4]−, which causes the RTP to quench. The ΔIp value is directly proportional to the concentration of Hg2+ in the range of 0.016–1.6 fg spot−1 (corresponding concentration: 0.040–4.0 pg ml−1, 0.40 μl spot−1), and the regression equation of working cure is ΔIp=10.03+83.15 m Hg2+ (fg spot−1), (r=0.9987, n=6) and the detection limit (LD) is 3.6 ag spot−1(corresponding concentration: 9.0×10–15 g ml−1, the sample volume: 0.4 μl). This simple, rapid, accurate method is of high selectivity and good repeatability, and it has been successfully applied to the determination of trace mercury in real samples. The reaction mechanism for catalyzing H2O2 oxidizing the ion association complex ([Sn(XO)6]4+·[(Fin)4]−) SS-RTP quenching method to determine trace mercury is also discussed. 相似文献
114.
H. Sakuma T. Taniyama K. Ishii Y. Kitamoto Y. Yamazaki 《Journal of magnetism and magnetic materials》2006,300(2):284-292
The order parameter S of Fe–Pt nanoparticles is estimated from X-ray diffraction (XRD) patterns. The total intensity of a diffraction peak is obtained by Rietveld analysis as well as simply integrating the intensity. The Rietveld analysis is found to provide a plausible value of S even for a sample showing an XRD pattern with broad and overlapped peaks. Another order parameter Q, which is obtained from Mössbauer spectra, is introduced, and it is confirmed that Q is equivalent to the probability of Fe atoms being in the L10-type atomic arrangement. The coercivity of Fe–Pt nanoparticles is directly proportional to Q, while it vanishes at S=0.4, indicating that the magnetic property of Fe–Pt nanoparticles has a closer relationship to Q than S. 相似文献
115.
Correlations of active galactic nuclei (AGNs) with microquasars are discussed based on the coexistence of the Blandford-Znajek (BZ) and magnetic coupling (MC) processes (CEBZMC) in black hole (BH) accretion disk.The proportions of several quantities of BH systems for both AGNs and microquasars are derived by combining the observational data with CEBZMC. It is shown that the square of the magnetic field at the BH horizon is inversely proportional to the BH mass, while the accretion rate of the disk is proportional to the BH mass. In addition, the very steep emissivity indexes from the recent XMM-Newton observations of the nearby bright Seyfert 1 galaxy MCG-6-30-15 and the microquasars XTE J1650-500 are well fitted by considering the MC effects on the disk radiation. These results suggest strongly the correlations of A GNs with microquasars. 相似文献
116.
117.
S. Alon-Braitbart E. Poem L. Fradkin N. Akopian S. Vilan E. Lifshitz E. Ehrenfreund D. Gershoni B.D. Gerardot A. Badolato P.M. Petroff 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):127
We fully characterize the fine spectral structure of neutral and negatively charged single microcavity quantum dot excitons, using polarization-sensitive magneto-photoluminescence spectroscopy. We show that the microcavity allows the simultaneous detection of both the bright and dark excitons using Faraday configuration. Thus, we were able to fully determine the fine structure and the g-factors of the neutral and negatively charged single exciton states within the same single quantum dot. Our measurements are in excellent agreement with novel, many carrier model calculations, which take into account Coulomb and exchange interactions among all the confined e–h pair states. 相似文献
118.
An easy way to controllably synthesize one-dimensional Sm B_6 topological insulator nanostructures and exploration of their field emission applications 下载免费PDF全文
A convenient fabrication technique for samarium hexaboride(SmB_6) nanostructures(nanowires and nanopencils) is developed, combining magnetron-sputtering and chemical vapor deposition. Both nanostructures are proven to be single crystals with cubic structure, and they both grow along the [001] direction. Formation of both nanostructures is attributed to the vapor-liquid-solid(VLS) mechanism, and the content of boron vapor is proposed to be the reason for their different morphologies at various evaporation distances. Field emission(FE) measurements show that the maximum current density of both the as-grown nanowires and nanopencils can be several hundred μA/cm~2, and their FN plots deviate only slightly from a straight line. Moreover, we prefer the generalized Schottky-Nordheim(SN) model to comprehend the difference in FE properties between the nanowires and nanopencils. The results reveal that the nonlinearity of FN plots is attributable to the effect of image potential on the FE process, which is almost independent of the morphology of the nanostructures.All the research results suggest that the SmB_6 nanostructures would have a more promising future in the FE area if their surface oxide layer was eliminated in advance. 相似文献
119.
We report the results of Monte Carlo simulation of the phase diagram and oxygen ordering in YBa2Cu3O6+x
for low intra-sublattice repulsion. At low temperatures, apart from tetragonal (T), orthorhombic (OI) and ‘double cell’ ortho II phases, there is evidence for two additional orthorhombic phases labelled here asOI andOIII. At high temperatures, there was no evidence for the decomposition of theOI phase into theT andOI phases. We find qualitative agreement with experimental observations and cluster-variation method results. 相似文献
120.
A. N. Andreyev D. D. Bogdanov V. I. Chepigin A. P. Kabachenko O. N. Malyshev Yu. Ts. Oganessian R. N. Sagajdak G. M. Ter-Akopian A. V. Yeremin F. P. Hessberger S. Hofmann V. Ninov M. Florek S. Saro M. Veselsky 《Zeitschrift für Physik A Hadrons and Nuclei》1992,344(2):225-226
The neutron-deficient isotopes257,258105 were produced in the reaction27Al+236u in 6n and 5n evaporation channels, respectively. The evaporation residues emerging from the target were separated in-flight from the projectiles and from products of different nuclear reactions by the electrostatic separator VASSILISSA [1]. The isotopes were then implanted into position-sensitive silicon detectors and identified using the --correlation method. The measured production cross-section is (5n)=(0.45±0.20)nb atE
P
=154 MeV and (6n)=(0.075±0.055) nb atE
P
=163 MeV. These cross-sections are compared with data measured for the same isotopes in the more symmetrical reaction50Ti+209Bi. 相似文献