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101.
Gyula Tasi István Pálinkó Fujio Mizukami 《Reaction Kinetics and Catalysis Letters》2001,74(2):317-322
A first principle quantum chemical method for determining the shape of molecules has been elaborated and its value in interpreting the experimentally found shape selectivity in isopropylation of isopropylnaphthalene on H-mordenite zeolite is demonstrated. In line with experimental results, it is found that 2,6-diisopropylnaphthalene is the most feasible product since it diffuses through the main channels of mordenite the easiest among the possible isomers. 相似文献
102.
Tetsuji Itoh Ryo Ishii Shun-ichi Matsuura Junko Mizuguchi Satoshi Hamakawa Taka-aki Hanaoka Tatsuo Tsunoda Fujio Mizukami 《Colloids and surfaces. B, Biointerfaces》2010,75(2):478-482
We assembled a highly durable conjugate with both a high-density accumulation and a regular array of lipase, by encapsulating it in mesoporous silica (FSM) with alkyltrimethylammonium (CTAB) chains on the surface. The activity for hydrolyzing esters of the lipase immobilized in mesoporous silica was linearly related to the concentration of lipase, whereas that of non-immobilized lipase showed saturation due to self-aggregation at a high concentration. The lipase conjugate also had increased resistance to heating when stayed in the silica coupling with CTAB. In addition, encapsulating the enzyme with FSM coupled CTAB caused the lipase to remain stable even in the presence of urea and trypsin, suggesting that the encapsulation prevented dissociation and denaturing. This conjugate had much higher activity and much higher stability for hydrolyzing esters when compared to the native lipase. These results show that FSM provides suitable support for the immobilization and dispersion of proteins in mesopores with disintegration of the aggregates. 相似文献
103.
Three-dimensional measurement of void fraction in a bubble plume using statistic stereoscopic image processing 总被引:6,自引:0,他引:6
A method for measuring the instantaneous 3-D bubble distribution in bubbly flows is proposed by making use of stereoscopic
image processing. The method applies to the case of higher rather than dilute void fractions, because it is based on the following
two statistic-based procedures. The first process is to obtain the 2-D distribution of local void fraction from visualized
images, where a correlation between the bubble shadow fraction and the projection void fraction is derived by introducing
the new idea of overlapping probability of the bubble-images under various conditions. The second process is to reconstruct
the 3-D distribution of the local void fraction. In this step, a logical method is proposed in order to obtain the bubble-existence
probability function which simultaneously satisfies the two distributions of the two projection void fractions. The present
method is applied for instantaneous measurement of the 3-D structure of a bubble plume. The measured results show its particular
structure, such as the hollow distribution of the bubbles, and the local spiral structure, which cannot be captured by point-measurement
experiments.
Received: 5 January 1999/Accepted: 3 February 2000 相似文献
104.
Nara TY Togashi H Sekikawa C Kawakami M Yaginuma N Sakaguchi K Mizukami F Tsunoda T 《Colloids and surfaces. B, Biointerfaces》2009,68(1):68-73
Zeolites are microporous crystalline aluminosilicates with a highly ordered structure. Using zeolite beta as an adsorbent, denatured/reduced hen egg lysozyme was refolded to the active form at high concentrations. The denatured/reduced lysozyme was adsorbed onto the zeolite and the protein was refolded by desorbing it into refolding buffer, consisting of redox reagents, guanidine hydrochloride, polyethylene glycol, and L-arginine. This zeolite refolding method could be highly effective for various kinds of proteins, refolding them with high efficiency even when they contain disulfide bonds. 相似文献
105.
J Han J Zhu Y Li X Yu S Wang G Wu H Xie SC Vogel F Izumi K Momma Y Kawamura Y Huang JB Goodenough Y Zhao 《Chemical communications (Cambridge, England)》2012,48(79):9840-9842
The evolution of the Li-ion displacements in the 3D interstitial pathways of the cubic garnet-type Li(7)La(3)Zr(2)O(12), cubic Li(7)La(3)Zr(2)O(12), was investigated with high-temperature neutron diffraction (HTND) from RT to 600 °C; the maximum-entropy method (MEM) was applied to estimate the Li nuclear-density distribution. Temperature-driven Li displacements were observed; the displacements indicate that the conduction pathways in the garnet framework are restricted to diffusion through the tetrahedral sites of the interstitial space. 相似文献
106.
107.
Shuji Tsubaki Naoki Fujita Fujio Wakaya Yoshihiko Yuba Kenji Gamo 《Superlattices and Microstructures》2000,27(5-6)
Series of double quantum dots each with a size around 400 × 400nm2 have been realized by delineating a 2DEG in modulation-doped AlGaAs/GaAs with 100 nm wide Schottky split gates fabricated by an electron-beam lithography and a lift-off technique. The split gate in the middle of the double dot allows us to control interdot coupling widely. The charging diagram obtained from linear transports in the Coulomb blockade regime shows that the isolated dots merge into a single composite dot with increase of interdot coupling. A clear Coulomb staircase has been observed in the double-dot system at a limited high-bias condition. 相似文献
108.
109.
110.
In order to establish the tosylated positions of α- and β-cyclodextrins, 13C-nmr spectra for the monotosyl-derivatives prepared in an alkaline aqueous solution were examined and determined to be in the 6-position of one glucose unit for β-cyclodextrin and to be in the C-2 position for α-cyclodextrin. 相似文献