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71.
72.
Efficient fabrication and enhanced photocatalytic activities of 3D-ordered films of titania hollow spheres 总被引:2,自引:0,他引:2
Facile and effective approaches were developed to fabricate 3D-ordered films of titania hollow spheres with different sphere diameters. The shell thickness of the sphere was adjusted in the range of 20-40 nm by changing the casting cycle of the titania precursor. The photonic stop band was observed for the 3D-ordered film and was tunable by the sphere diameter and the shell thickness. The stop band shifted from 930 to 547 nm. Crystal violet dye adsorbed on the film exhibited more than two times higher absorbance than that on a reference film of a flat titania layer, probably due to the red edge effect of the stop band and/or to the multiple scattering effect. The enhanced absorbance led to more efficient photodegradation of the dye under visible light and under solar light irradiation. A maximum photocatalytic enhancement of 22% is achieved. Finally, the influence of TiO2 morphology on photocatalytic activity was discussed. Compared with flat titania films, the existence of ordered macropores in titania spheres causes the stop band and a longer optical path due to multiple scattering. Both the red edge of the stop band and multiple scattering effects enhance the absorption of the dye, which results in the photocatalytic enhancement. 相似文献
73.
74.
M. Ogura T. Nagatomo K. Minamisomo K. Matsuta T. Minamisono Y. Nakashima C. D. P. Levy T. Sumikama M. Mihara H. Fujiwara S. Kumashiro M. Fukuda J. A. Behr K. P. Jackson S. Momota Y. Nojiri T. Ohtsubo M. Ohta A. Kitagawa M. Kanazawa M. Torikoshi S. Sato M. Suda J. R. Alonso G. F. Krebs T. M. Symons 《Hyperfine Interactions》2004,159(1-4):235-238
The electric quadrupole coupling constants eqQ/h of 20Na (I
π = 2+, T
1/2 = 449.7 ms), 21Na (I
π = 3/2, T
1/2 = 22.49 s) and 25Na (I
π = 5/2, T
1/2 = 59.6 s) in single crystal ZnO and TiO2 were precisely measured by applying the β-NMR technique. The ratio of the quadrupole moments between 20Na (25Na) and 21Na was determined to be 0.728 ± 0.023 (0.011 ± 0.002). 相似文献
75.
Radical polymerizations of divinylformal were carried out with AIBN initiator in several solvents. In many solvents (benzene, cyclohexane, acetonitrile, DMSO, etc.), the polymers consisted of the cyclized monomer unit and 5 to 8= of the pendant formate group. The amounts of the residual vinyl group were quite small in these solvents. The formate group was probably formed by the hydrogen migration and the subsequent ring scission of the cyclic propagating radical. On the other hand, a polymer obtained in CS2 contained about 30= of the pendant vinyl group but no formate group. In addition, the carbon and hydrogen contents of this polymer were lower than expected, and sulfur was detected instead. The polymerization in benzene-CS2 mixtures indicated a much stronger influence of CS2 than benzene. These results suggest that CS2 molecules interact strongly with the propagating radical to the extent that it can be incorporated into polymer. 相似文献
76.
S. Momota M. Kanazawa A. Kitagawa S. Sato Y. Nojiri 《The European physical journal. Special topics》2007,150(1):315-316
The longitudinal and transverse momentum (PL and PYenT) distributions of projectile-like fragments, which were produced with an Ar beam and various targets (C, Al, Nb, Tb, Au),
were measured at E=290A MeV. No significant target effects are found in P L distribution. The width of PT distribution increases with target mass. It is plausible that this result is explained by the deflection of orbit arising
from Coulomb repulsion. The nuclear structural effects are observed in isotopic and isotonic distributions of production cross-sections
of fragments, which are derived from observed momentum distributions. 相似文献
77.
Y. Nojiri S. Momota T. Yanagisawa M. -B. Tanaka M. Fukuda K. Matsuta T. Minamisono 《Hyperfine Interactions》1993,78(1-4):567-571
To complete the systematic study on hyperfine interactions of light impurities in ferromagnetic Ni, the short-lived beta-emitter8Li was implanted in a thin polycrystal Ni foil. One of the final sites of8Li in Ni was found by means of the beta-NMR technique andits hyperfine field was determined to be -3.65(3) kOe. Simultaneously, the spin lattice relaxation time of8Li at the site in Ni was found to be 1.6(4) s. Based on the comparison between these values and theoretical predictions recently made by a first principle calculation, the probable site of8Li in Ni is implied to be an octahedral interstitial site. 相似文献
78.
Shin-ichiro Sakurai Akihiro Ohira Yoshinori Suzuki Riri Fujito Tatsuya Nishimura Masashi Kunitake Eiji Yashima 《Journal of polymer science. Part A, Polymer chemistry》2004,42(18):4621-4640
Novel sets of helical poly(phenylacetylene)s bearing a chiral ruthenium (Ru) complex with opposite chirality (Δ and Λ forms) as a bulky pendant (poly- 1 and poly- 2 ) were synthesized through the polymerization of the corresponding optically pure phenylacetylenes with a rhodium catalyst, and their structures in solution and morphology on solid substrates were investigated with NMR, ultraviolet–visible, and circular dichroism (CD) spectroscopies and with atomic force microscopy (AFM), respectively. The obtained cis–transoidal polymers (poly- 1 and poly- 2 ) showed characteristic Cotton effects in the region of metal-to-ligand charge transfer of the chiral Ru pendants. Poly- 1 and poly- 2 were thought to have a predominantly one-handed helical conformation induced by the chiral pendants. However, the apparent Cotton effects derived from the helically twisted π-conjugated polymer backbone could not be observed, probably because of the strong chiral chromophoric pendants. However, in the AFM images, the helical polymers adsorbed on mica could be easily discerned as isolated strands, and the visualization and discrimination of the right- and left-handed helical structures of the chiral polymers were achieved by high-resolution AFM imaging. On the basis of the AFM observations together with the CD measurements and computational calculation results, possible structures of poly- 1 and poly- 2 were examined. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4621–4640, 2004 相似文献
79.
Y. Hirayama M. Mihara Y. X. Watanabe S. C. Jeong N. Imai K. Matsuta H. Miyatake T. Hashimoto H. Ishiyama S. Ichikawa T. Ishii T. Izumikawa I. Katayama H. Kawakami I. Nishinaka K. Nishio H. Makii S. Mitsuoka S. Momota A. Osa Y. Otokawa T. K. Sato Y. Wakabayashi 《The European Physical Journal A - Hadrons and Nuclei》2011,47(11):1-5
A spin-polarized radioactive 123In (I π , g = 1.220(2) , T 1/2 = 5.97(5) s) beam has been successfully generated by the tilted-foil method. This nuclide is the heaviest ever polarized in its ground state by this method. Using the ISOL-based re-acceleration-type facility TRIAC, an 123Ing.s. beam of 305 keV/nucleon went through a stack of 15 carbon foils with a tilt angle of 70° , and an asymmetry of 0.76 ± 0.25% of β-decays was observed by the β-NMR technique. The asymmetry shows that the tilted-foil method combined with a re-acceleration facility is useful for producing spin-polarized beams for applications such as nuclear physics and materials science. 相似文献
80.
ZHENG Yong-Nan ZHOU Dong-Mei K. Matsuta M. Mihara M. Fukuda D. Nishimura J. Komurasaki D. Ishikawa R. Matsumiya T. Nagatomo T. Izumikawa S. Takahashi H. Hirano T. Ohtsubo S. Momota Y. Nojiri A. Kitagawa M. Kanazawa M. Torikoshi S. Sato T. Minamisono J.R. Alonso G.F. Krebs T. J. M. Symons YUAN Da-Qing ZUO Yi FAN Ping T. Suzuki ZHANG Xi-Zhen ZHU Sheng-Yun 《中国物理C(英文版)》2009,33(Z1)
Nuclear structure of proton-rich unstable nucleus 28P has been studied by measuring its g-factor for the first time. The g-factor of 28P (Iπ =3+, T1/2=270.3 ms) was measured by means of β-NMR technique combined with the new polarization technique for charge exchange reaction product in the intermediate energy heavy ion collisions. The obtained g-factor of g=0.1028(27) is very much quenched from the Schmidt value,but is well reproduced by the shell model (+0.102). In connection with the magnetic moment of the mirror partner and the β-ray transition probability, the orbital angular momenta and intrinsic spins of protons and neutrons have been determined as 〈lp〉 = 0.43(29), 〈ln〉 = 1.85(29), 〈Sp〉 = 0.28(4), and 〈Sn〉 = 0.44(4). 相似文献