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991.
Improved dehydrogenation/rehydrogenation performance of LiBH4 by doping mesoporous Fe2O3 or/and TiF3
Hui Zhang Zhong Cao Li-Xian Sun Yu-Jia Sun Fen Xu Hui Liu Jian Zhang Zi-Qiang Huang Xia Jiang Zhi-Bao Li Shuang Liu Shuang Wang Cheng-Li Jiao Huai-Ying Zhou Yutaka Sawada 《Journal of Thermal Analysis and Calorimetry》2013,112(3):1407-1414
The LiBH4 + mesoporous Fe2O3 (defined as M-Fe2O3) mono-doped and LiBH4 + M-Fe2O3 + TiF3 co-doped hybrid materials were prepared by ball milling process. A variety of characterization methods, such as thermogravimetric, differential scanning calorimetry, X-ray diffraction, and pressure–composition–temperature instrument, were used for examinations of the two materials’ performances of storage/release of hydrogen, catalytic activity, kinetics, and thermodynamics. All the results showed that the M-Fe2O3 prepared in laboratory exhibited a good catalytic effect. Compared with the performance of M-Fe2O3 mono-doped system, M-Fe2O3 and TiF3 co-doped mode exhibits a better performance using the same additive content. Thus, the M-Fe2O3 and TiF3 co-doped mode possesses a collaborative catalytic utility with the LiBH4 hydrogen performance improved, showing a promising application. 相似文献
992.
Akira Sekiguchi Yutaka Ishida 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1317-1322
Abstract The halogen-substituted cyclotrigermenes (tBu3Si)3Ge3X (X = F, Cl, Br, I) (2) were synthesized by the reaction of tris(tri-tert-butylsilyl)cyclotrigermenylium tetrakis(2,3,5,6-tetrafluorophenyl)borate) (1 +?TTFPB?) with potassium halides (KF, KCl, KBr, KI). Intramolecular halogen migration over the three-membered ring skeleton was observed in the solution. GRAPHICAL ABSTRACT 相似文献
993.
Yoichi Ogata Kazuhiro Iso Satoshi Kura Toshiyuki Hayakawa Yutaka Makita 《Journal of Polymer Science.Polymer Physics》2010,48(15):1740-1748
Solution property of poly(γ‐benzyl‐L ‐glutamate)‐b‐polyisoprene‐b‐poly(γ‐benzyl‐L ‐glutamate) (GIG copolymer) was studied by using dynamic light scattering and static light scattering for N,N‐dimethylformamide (DMF) solution and DMF/toluene mixed solutions. GIG copolymer proved to aggregate in DMF and under DMF‐rich condition, that is, high‐polar region. The aggregate decreased in size, and completely disappeared under toluene‐rich condition, that is, low‐polar region. The correlation between solubility parameter and aggregate size of GIG copolymer in the DMF/toluene solution systems quantitatively demonstrated how strongly polarity caused by hydrogen bond made an impact on the aggregation behavior. Because the main driving force to the aggregation under DMF‐rich condition originates with polyisoprene (PIP) blocks, the aggregate in DMF is considered to be a core‐shell micelle consisting of flexible PIP core surrounded by rigid poly(γ‐benzyl‐L ‐glutamate) (PBLG) shell. The values of dimensionless parameter ρ, defined as the ratio of radius of gyration 〈S2〉1/2 to hydrodynamic radius RH, revealed that a single chain of GIG copolymer had the form of rigid rod with flexibility, that is, once‐broken rod, caused by the incorporation of a flexible PIP chain between two rigid PBLG rods in the DMF/toluene solution system. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1740–1748, 2010 相似文献
994.
PZT films with different microstructure and Zr:Ti ratios were fabricated on ITO/glass and platinized silicon wafer substrates
by dip-coating. A dense film of 2% porosity and a porous film of 19% porosity were obtained by repetition of thin and thick
coatings, respectively. Development of pores during heating the film was examined and heating process factors were investigated.
In the film fabricated on ITO/glass substrates, an existence of non-perovskite and low permittivity layer was confirmed by
measurement of film thickness dependence of the dielectric constant. Among the films studied, the film with molar composition
of Ti:Zr = 5:5 exhibited the largest dielectric constant and apparent piezoelectric coefficient, d
33, though the values were small. Apparent piezoelectric coefficients of d
33 and g
33 of the porous films were larger than those of the dense films. 相似文献
995.
996.
Enumerating Constrained Non-crossing Minimally Rigid Frameworks 总被引:2,自引:1,他引:1
David Avis Naoki Katoh Makoto Ohsaki Ileana Streinu Shin-ichi Tanigawa 《Discrete and Computational Geometry》2008,40(1):31-46
In this paper we present an algorithm for enumerating without repetitions all the non-crossing generically minimally rigid
bar-and-joint frameworks under edge constraints, which we call constrained non-crossing Laman frameworks, on a given set of
n points in the plane. Our algorithm is based on the reverse search paradigm of Avis and Fukuda. It generates each output graph
in O(n
4) time and O(n) space, or, with a slightly different implementation, in O(n
3) time and O(n
2) space. In particular, we obtain that the set of all the constrained non-crossing Laman frameworks on a given point set is
connected by flips which preserve the Laman property.
D. Avis’s research was supported by NSERC and FQRNT grants.
N. Katoh’s, M. Ohsaki’s and S.-i. Tanigawa’s research was supported by NEXT Grant-in-Aid for Scientific Research on priority
areas of New Horizons in Computing.
I. Streinu’s research was supported by NSF grant CCF-0430990 and NSF-DARPA CARGO CCR-0310661. 相似文献
997.
Yutaka Nishigaichi Akira Suzuki Takahiro Saito Akio Takuwa 《Tetrahedron letters》2005,46(31):5149-5151
Hypervalency (pentacoordination) of silicon atom enhanced photoallylation of 1,2-diketones with allylsilicon reagents, while normal tetracoordinated ones could not. This reaction seems to proceed via photoinduced electron transfer from the silicon reagent to the photoexcited ketone judged from its reactivity and selectivity. 相似文献
998.
Yutaka Ishii 《Communications in Mathematical Physics》1997,190(2):375-394
We construct a kneading theory à la Milnor–Thurston for Lozi mappings (piecewise affine homeomorphisms of the plane). In the first article a two-dimensional
analogue of the kneading sequence called the pruning pair is defined, and a topological model of a Lozi mapping is constructed
in terms of the pruning pair only. As an application of this result, in the current paper we show the partial monotonicity
of the topological entropy and of bifurcations for the Lozi family near horseshoes. Upper and lower bounds for the Hausdorff
dimension of the Lozi attractor are also given in terms of parameters.
Dédié au Professeur A. Douady pour son 60ème anniversaire
Received: 1 September 1996 / Accepted: 16 April 1997 相似文献
999.
1000.