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111.
Ikeda S Kobayashi H Ikoma Y Harada T Torimoto T Ohtani B Matsumura M 《Physical chemistry chemical physics : PCCP》2007,9(48):6319-6326
A novel core-shell composite photocatalyst, commercially available titanium(IV) oxide (TiO(2)) particles directly incorporated into a hollow amorphous silica shell, was fabricated by successive coating of TiO(2) with a carbon layer and a silica layer followed by heat treatment to remove the carbon layer. The composite induced efficient photocatalytic reactions when relatively small substrates were used, such as methanol dehydration and decomposition of acetic acid, without any reduction in the intrinsic activity of original TiO(2), but did not exhibit efficient photocatalytic activity for decomposition of large substrates, methylene blue and polyvinyl alcohol. The unique size-selective properties of the composites are due to their structural characteristics, i.e., the presence of a pore system and a void space in the silica shell and between the shell and medial TiO(2) particles, respectively. The loading of alkylsilyl groups on the surface of the composite led to highly photostable floatability: the floated sample also induced efficient photocatalytic reaction for decomposition of acetic acid while retaining floatation at the gas/water interface. 相似文献
112.
Onodera K Hirano-Iwata A Miyamoto K Kimura Y Kataoka M Shinohara Y Niwano M 《Langmuir : the ACS journal of surfaces and colloids》2007,23(24):12287-12292
Here, we propose a label-free detection of protein-protein interactions that enables simultaneous qualitative analysis of target proteins by using Fourier transform infrared (FTIR) absorption spectroscopy in multiple internal reflection geometry (MIR-FTIR). Using this method, the target proteins were detected based on the peak height of the amide I and amide II bands, while discrimination of specific and nonspecific signals is made based on the secondary structure of the analytes, which is determined through second-derivative analysis of the amide I band. As a model system, an antigen peptide was immobilized on the surface of GaAs, which was transparent to mid-infrared light, and the interaction with its antibody was examined in aqueous media. We demonstrated that the binding of the antibody to the antigen immobilized on a GaAs surface selectively gave rise to beta-sheet amide I vibrations (1639 and 1690 cm-1), while no structurally related signals were induced by nonspecifically adsorbed proteins. The peak height of the beta-peak (1639 cm-1) in the amide I band linearly increased with the antiserum concentration as well as that of the amide II band. The detection limit (S/N = 3) was a 1:36 000 dilution for the amide I signal. In addition, through the use of surface-sensitive MIR-FTIR, the present sensor selectively detected the antigen-antibody interactions at the surfaces without being affected by the presence of bulk species, enabling rapid and wash-free detection. Our method provides not only rapid label-free detection of protein-protein interactions but a more accurate discrimination between specific and nonspecific interactions through the use of the secondary structure of the target proteins as a measure for the specific signals. 相似文献
113.
A closed subspace is said to be invariant if it is invariant under the Toeplitz operators and . Invariant subspaces of are well-known to be very complicated. So discovering some good examples of invariant subspaces will be beneficial to the general study. This paper studies a type of invariant subspace constructed through a sequence of inner functions. It will be shown that this type of invariant subspace has direct connections with the Jordan operator. Related calculations also give rise to a simple upper bound for , where are zeros of a Blaschke product.
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116.
Kazuya Saito Yasuhiro Takahashi Michio Sorai 《Journal of Polymer Science.Polymer Physics》2000,38(12):1584-1588
The heat capacity of crystalline poly(p‐phenylenebenzobisoxazole) was measured below room temperature by adiabatic calorimetry. The standard thermodynamic functions (enthalpy, entropy, and Gibbs energy) were established and tabulated. The temperature dependence of the heat capacity was compared with those of polyethylene and poly(p‐phenylene), with attention paid to the low dimensionality of the systems. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1584–1588, 2000 相似文献
117.
Ultrasound of 2MHz was irradiated to the emulsion prepared from canola oil and water and flocculation of the oil droplets occurred immediately. By putting the emulsion sample in a thin glass cell and setting it in bath type irradiation equipment, the progress of the separation was quantitatively monitored with the optical absorbance. The use of the cell enables visual observation of the behavior of oil droplets. Pictures show the formation of flocks of the dispersed phase and the appearance of checkered pattern consisting of flocks at a regular interval. The observation indicates that the action of radiation forces on oil droplets, which causes the flocculation. The flocks started to rise after stopping irradiation with holding their shape. The rising rate of the flocks was significantly greater than that of oil droplets in the original emulsion. Ultrasonic irradiation caused a rapid decrease in the absorbance, which expresses a progress of the separation. Effects of two major operation parameters, power and time on the separation degree were examined. The degree improved with increasing power input and irradiation time. The dataset was arranged in a plot of normalized separation degree against the input energy. The plot suggests that effective separation was attained with a lower power input and a longer irradiation time. The plot provides a guide for setting condition for the separation. 相似文献
118.
Hideaki Tokuyama Hiroshi Sumida Akifumi Kanehara Susumu Nii 《Colloid and polymer science》2009,287(1):115-121
Stimuli-sensitive porous hydrogels prepared with an emulsion templating method developed by the authors are potentially applicable
in the medical and pharmaceutical fields; thermosensitive N-isopropylacrylamide (NIPA) hydrogels having randomly distributed sphere-like cavities have been prepared by the polymerization
in an aqueous phase in an oil-in-water (O/W) emulsion, followed by the washing of oil (oleyl alcohol) microdroplets. The surfactant
plays a dominant role in the preparation of porous hydrogels and the pore size. This study concerns with the surfactant effects
on the stability of pre-gel O/W emulsions. The porous NIPA hydrogels were successfully prepared using the surfactants forming
the stable emulsion and their internal structures and swelling properties were characterized. The O/W emulsions and the porous
hydrogels prepared using various amounts of oil and surfactant were characterized. The information obtained serves for preparation
of porous hydrogels having suitable porous structure for their applications. 相似文献
119.
Ryoji Kobori Tomonori Ohba Takaomi Suzuki Taku Iiyama Sumio Ozeki Michio Inagaki Akihiro Nakamura Masato Kawai Hirofumi Kanoh Katsumi Kaneko 《Adsorption》2009,15(2):114-122
N2 adsorption isotherms of molecular sieve carbon were measured at 77 K and 303 K. The Ar adsorption isotherms of molecular
sieve carbon samples were also measured at 303 K. The grand canonical Monte Carlo (GCMC) simulation technique was applied
to calculate the N2 and Ar adsorption isotherms at 303 K using the ultramicropore volume determined by H2O adsorption. The comparative method of experimental and simulated isotherms of supercritical N2 and Ar at 303 K gave the width of the micropore mouth of the molecular sieve carbon, which can be applied to the ultramicropore
width determination for other noncrystalline porous solids. 相似文献
120.
Fractionation of methanol extracts of the fruit bodies of two inedible mushrooms Hydnellum suaveolens and Hydnellum geogerirum (Thelephoraceae) resulted in isolation of two new p-terphenyl derivatives named hydnellins A and B and sarcodonin delta possessing N-oxide. Their structures were determined by 2D NMR, IR, UV spectroscopy, and chemical reaction. These terphenyls showed moderate antioxidant activity. 相似文献