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81.
Nishiyama Y Tanaka S Hillhouse HW Nishiyama N Egashira Y Ueyama K 《Langmuir : the ACS journal of surfaces and colloids》2006,22(23):9469-9472
Ordered mesoporous zirconium phosphate films were prepared on a silicon substrate by spin coating using a mixture of zirconium isopropoxide, triethyl phosphate, Pluronic P123 triblock copolymer, nitric acid, ethanol, and water. The spin-on film was consecutively treated with vapors of phosphoric acid and ammonia. The post-vapor treatments effectively enhanced the thermal stability of an ordered mesostructure when heated to 500 degrees C. XRD and TEM analyses show that the calcined zirconium phosphate film has a hexagonal structure with straight channels parallel to the film surface. The zirconium phosphate film exhibited high proton conductivity of 0.02 S/cm parallel to the film surface at 80% RH and 25 degrees C. 相似文献
82.
Terashima Yukio Sugimoto Naoyuki Mori Manami Kinoshita Norikazu Takeda Kiyoshi 《Journal of Thermal Analysis and Calorimetry》2019,135(5):2797-2805
Journal of Thermal Analysis and Calorimetry - We have used differential scanning calorimetry (DSC) to investigate the thermodynamic and kinetic properties of the glass transition of simple amine... 相似文献
83.
The statistical properties of earthquake aftershocks are studied. The scaling relation for exponents of the Omori law and the power-law calm time distribution (i.e., the interoccurrence time distribution), which is valid if a sequence of aftershocks is a singular Markovian process, is carefully examined. Data analysis shows significant violation of the scaling relation, implying the non-Markovian nature of aftershocks. 相似文献
84.
Scaling relation for earthquake networks 总被引:1,自引:0,他引:1
The scaling relation, 2γ−δ=1, for the exponents of the power-law connectivity distribution, γ, and the power-law eigenvalue distribution of the adjacency matrix, δ, is theoretically predicted to be fulfilled by a locally treelike scale-free network in the “effective medium approximation” (i.e., an analog of the mean field approximation). Here, it is shown that such a relation holds well for the reduced simple earthquake networks (i.e., the network without tadpole-loops and multiple edges) constructed from the seismic data taken from California and Japan. This validates the goodness of the effective medium approximation in the earthquake networks and is consistent with the hierarchical organization of the networks. The present result may be useful for modeling seismicity on complex networks. 相似文献
85.
Conservative upwind finite-element method for a simplified Keller-Segel system modelling chemotaxis 总被引:2,自引:0,他引:2
** Email: saito{at}infsup.jp Finite-element approximation for a non-linear parabolicellipticsystem is considered. The system describes the aggregation ofslime moulds resulting from their chemotactic features and iscalled a simplified KellerSegel system. Applying an upwindtechnique, first we present a finite-element scheme that satisfiesboth positivity and mass conservation properties. Consequently,if the triangulation is of acute type, our finite-element approximationpreserves the L1 norm, which is an important property of theoriginal system. Then, under some assumptions on the regularityof a solution and on the triangulation, we establish error estimatesin Lp x W1, with a suitable p > d, where d is the dimensionof a spatial domain. Our scheme is well suited for practicalcomputations. Some numerical examples that validate our theoreticalresults are also presented. 相似文献
86.
Nishiyama N Kaihara J Nishiyama Y Egashira Y Ueyama K 《Langmuir : the ACS journal of surfaces and colloids》2007,23(9):4746-4748
Mesoporous SiO2-P2O5 films were synthesized from the vapor phase onto a silicon substrate. First, a precursor solution of cetyltrimethylammonium bromide (C16TAB), H3PO4, ethanol, and water was deposited on a silicon substrate by a spin-coating method. Then, the C16TAB-H3PO4 composite film was treated with tetraethoxysilane (TEOS) vapor at 90-180 degrees C for 2.5 h. The H3PO4-C16TAB composite formed a hexagonal structure on the silicon substrate before vapor treatment. The TEOS molecules penetrated into the film without a phase transition. The periodic mesostructure of the SiO2-P2O5 films was retained after calcination. The calcined films showed a high proton conductivity of about 0.55 S/cm at room temperature. The molar ratio of P/Si in the SiO2-P2O5 film was as high as 0.43, a level that was not attained by a premixing sol-gel method. The high phosphate group content and the ordered periodic mesostructure contributed to the high proton conductivity. 相似文献
87.
A new and reliable procedure for constructing five- to seven-membered carbocycles via an endo-mode ring-closing reaction of 1-phenylsulfonylallenes with a substituent that has a terminal active methine moiety at the C1-position has been developed. Trisubstituted 1-phenylsulfonylallenes underwent a similar endo-mode ring-closing reaction to produce the corresponding five- to seven-membered carbocycles, while the formation of six- and seven-membered carbocycles from the corresponding tetrasubstituted allene was not realized. In addition, the introduction of an aromatic ring to the alkyl side chain of the starting allenes made possible the construction not only of normal-sized carbocycles but also an eight-membered framework. 相似文献
88.
Kato M Yamamoto H Okamura TA Maoka N Masui R Kuramitsu S Ueyama N 《Dalton transactions (Cambridge, England : 2003)》2005,(6):1023-1026
A 1:1 thioredoxin-Pt(bpy) complex was prepared by adding [Pt(bpy)(en)]Cl(2)(bpy = 2,2'-bipyridine, en = ethylenediamine) to Thermus thermophilus HB8 thioredoxin in pH 8 phosphate buffer. Matrix-assisted laser desorption-ionization time of flight mass spectrometry (MALDI-TOF MS) and UV spectra of indicate the formation of Pt(bpy)(cys-Ala-Pro-cys-containing peptide fragment). These findings suggest that the Pt(bpy)(2+) unit binds to the active site of thioredoxin. The thioredoxin-platinum complex has no catalytic activity for the reduction of glutathione disulfide in the presence of NADPH and thioredoxin reductase, so that the platinum complex functions as an inhibitor. 相似文献
89.
90.
Zheng‐Hua Zhang Shuang‐Yi Wan Taka‐aki Okamura Wei‐Yin Sun Norikazu Ueyama 《无机化学与普通化学杂志》2006,632(4):679-683
Two novel lanthanide coordination polymers, [La(tpaa)3(H2O)2] ( 1 ) and [Eu2(BDC)3(DMF)2(H2O)2] ( 2 ) (Htpaa = terephthalamic acid, H2BDC = 1,4‐benzenedicarboxylic acid, DMF = N,N‐dimethylformamide), were hydro(solvo)thermally synthesized by reactions of the corresponding lanthanide nitrate salts with 1,3,5‐triazine‐2,4,6‐tri(4‐benzenecarboxylate) ( L ), in which a simultaneous hydrolysis of the ligand L occurred. Single‐crystal X‐ray analysis revealed that complex 1 comprises one‐dimensional chains that are further interlinked via hydrogen bonds, resulting in a two‐dimensional network; while complex 2 is a three‐dimensional interpenetrated coordination architecture. 相似文献