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991.
Jin-Soo Hwang Jong-San Chang Sang-Eon Park Keita Ikeue Masakazu Anpo 《Topics in Catalysis》2005,35(3-4):311-319
Nanoporous photocatalysts have been designed to exhibit unique photocatalytic activities through framework substitution of
titanium species or surface immobilization of rhenium complex onto mesoporous silica. This article summarizes recent work
on the synthesis, characterization and photocatalytic activities of the designed porous photocatalysts performed by the present
authors. Various spectroscopic investigations revealed that the photo-excited states of these catalysts play a vital role
in the photocatalytic reactions and their photocatalytic reactivities are strongly dependent on structures of active sites,
which are confined and immobilized in the restricted framework structure of the mesoporous silica. Highly dispersed titanium
oxide species incorporated in the framework of mesoporous silica exhibited high and unique photocatalytic reactivity for the
reduction of CO2 with H2O to produce CH4 and CH3OH under UV irradiation, its reactivity being much higher than bulk TiO2. The cationic rhenium(I) complex was encapsulated into a mesoporous AlMCM-41 material by ion-exchange method, yielding a
visible light photocatalyst to be active for photocatalytic reduction of CO2. 相似文献
992.
Polymer membranes having cationic charge site, poly(1-alkyl-4-vinylpyridinium iodide-co-acrylonitrile) (alkyl: methyl, butyl, or octyl) were prepared in terms of coulombic interaction for separation of water–ethanol mixtures. The incorporation of cationic charge site into the membrane led to improve not only separation factors (selectivity toward water) but also flux number in the separation of aqueous ethanol solution by pervaporation technique. Target values, which were requested to have from the viewpoint of industrial utilization for separation of aqueous ethanol solution were attained as follows: separation factor toward water over 50 and flux value over 500 g m?2 h?1, through poly(1-methyl-4-vinylpyridinium iodide-co-acrylonitrile) (membrane 3 ) (quarternized fraction of pyridinium moiety, 89.5%; mol fraction of pyridinium moiety, 0.034) and poly(1-butyl-4-vinylpyridinium iodide-co-acrylonitrile) (membrane 5 ) (quarternized fraction, 100%; mol fraction of pyridinium moiety, 0.038). It was found that the introduction of cationic charge site into the membrane was one of feasible methods to obtain suitable membranes for water permselective membranes in the separation of water–ethanol mixtures. 相似文献
993.
Jinkai Zhou Masato Takeuchi X. S. Zhao Ajay K. Ray Masakazu Anpo 《Catalysis Letters》2006,106(1-2):67-70
Unique visible-light-responsive TiO2 photocatalysts (λ>450 nm) were successfully developed by implantation of V ions into the TiO2 thin films prepared on a quartz substrate by an ionized cluster beam (ICB) deposition method. After V ions implantation into
TiO2 thin film, the photocatalytic activity of the thin films for the decomposition of formic acid into CO2 and H2O was found to proceed efficiently under visible light irradiation longer than 450 nm. The TiO2 thin film photocatalysts were characterized by XRD, UV-vis, XPS, FE-SEM and AFM. 相似文献
994.
Jingye Li Shogo Ichizuri Saneto Asano Fumihiro Mutou Shigetoshi Ikeda Minoru Iida Takaharu Miura Akihiro Oshima Yoneho Tabata Masakazu Washio 《应用聚合物科学杂志》2006,101(6):3587-3599
Ion exchange membranes (IEMs) were prepared by preirradiation induced grafting of styrene with or without divinylbenzene (DVB) into crosslinked polytetrafluoroethylene (RX‐PTFE) films and successively sulfonated by chlorosulfonic acid. The effects of the DVB concentration and solvent on the kinetic of the graft polymerization were studied. The ion exchange capacity (IEC) values of the prepared membranes ranging from 1.5 to 2.8 mequiv/g were obtained. The degree of swelling increased with the increase in the degree of grafting, while higher crosslinking density of both the RX‐PTFE matrices and the grafts suppressed the degree of swelling. The chemical stabilities of the IEMs were tested by recording the weight of the membranes being soaked in hot H2O2 solutions. The weight‐time curves of the prepared membranes showed one‐step quick decrease due to the decomposition of the poly(styrene‐sulfonic acid) (PSSA) grafts. Higher crosslinking density in both the RX‐PTFE matrices and the grafts improved the chemical stability of the IEMs. The ionic conductivity of the IEMs increases with the increase in the IEC values. The IEMs with IEC values higher than 2.2 mequiv/g hold the higher ionic conductivity than that of Nafion® 112 membrane. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3587–3599, 2006 相似文献
995.
It is well known that the apparent reaction rate constant is increased by exposing the reactor to ultrasound. The authors reveal in this paper that another effect of ultrasound, that is, the decrease of the segregation of points in the sense of Danckwerts, also appears and that this effect is probably due to some hammering action caused by the collapse of cavities. The saponification of ethyl acetate in a continuous stirred tank reactor is chosen for the experimental work. 相似文献
996.
Tomohiro Oonaka Keiji Hashimoto Hiroshi Kominami Yoshiya Kera Yoshio Matsubara 《Catalysis Today》2006,111(3-4):354-360
A salt of ruthenium-containing polyoxomolybdate anion ([Ru2Mo14O50]10− or [Ru2Mo14O52]14−; Ru2Mo14) was synthesized by mixing ruthenium chloride and sodium molybdate in a buffer solution (acetic acid–ammonium acetate) at pH 5. The polyanion, Ru2Mo14, was loaded on a silica carrier chemically modified with a silane coupling agent having a 1,2-diaminoethyl group (DAPS–SiO2). X-ray diffraction, FT-IR and surface area measurements revealed that Ru2Mo14 was highly dispersed on DAPS–SiO2 up to 20 wt.% loading. The highly dispersed Ru2Mo14 exhibited a high level of activity for oxidative dehydrogenation of methanol to formaldehyde with a high selectivity, whereas combustion of methanol occurred on the bulky salt of Ru2Mo14 and ruthenium catalyst supported on a SiO2 carrier. 相似文献
997.
In this study, we investigated methanol (MeOH)/methyl tert‐butyl ether (MTBE) separation with hydroxyethylcellulose (HEC)/agarose blended membranes by applying a pervaporation technique. The membranes permeated MeOH in preference to MTBE from MeOH/MTBE mixtures. From pervaporation and sorption data, the permselectivity of HEC/agarose blended membrane was dominantly due to solubility selectivity. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3408–3411, 2002 相似文献
998.
Photocatalytic decomposition of NO on titanium oxide thin film photocatalysts prepared by an ionized cluster beam technique 总被引:1,自引:0,他引:1
Masato Takeuchi Hiromi Yamashita Masaya Matsuoka Masakazu Anpo Takashi Hirao Nobuhisa Itoh Nobuya Iwamoto 《Catalysis Letters》2000,66(3):185-187
Transparent TiO2 thin film photocatalysts were prepared on transparent porous Vycor glass (PVG) by an ionized cluster beam (ICB) method. The
UV‐VIS absorption spectra of these films show specific interference fringes, indicating that uniform and transparent TiO2 thin films are formed. The results of XRD measurements indicate that these TiO2 thin films consist of both anatase and rutile structures. UV light (λ > 270 nm) irradiation of these TiO2 thin films in the presence of NO led to the photocatalytic decomposition of NO into N2, O2 and N2O. The reactivity of these TiO2 thin films for the photocatalytic decomposition of NO is strongly dependent on the film thickness, i.e., the thinner the
TiO2 thin films, the higher the reactivity.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
999.
Raymonde Franck Nobuaki Negishi Sang-Chul Moon Masakazu Anpo Jean-Michel Tatibouët Michel Che 《Topics in Catalysis》1996,3(1-2):115-120
La2O3 catalysts prepared at 923 K (La2O3-LT) and 1073 K (La2O3-HT) exhibit different photoluminescence properties due to notably different concentrations of ions in position of low coordination
at the surface or coordinatively unsaturated surface sites (cus). The catalyst which exhibits the higher yields of photoluminescence
due to the higher concentration of cus corresponds to the one which gives the higher C2+ selectivity in the oxidative methane coupling reaction.
On leave of absence from Laboratoire de Réactivité de Surface, Université Pierre et Marie Curie, URA 1106-CNRS, 75252 Paris
Cedex, France. 相似文献
1000.
Shuai Yuan Qiaorong Sheng Jinlong Zhang Feng Chen Masakazu Anpo Weilin Dai 《Catalysis Letters》2006,107(1-2):19-24
A simple synthetic method to prepare highly dispersed Pd nanoparticles in La-doped mesoporous titania with polycrystalline
framework by coassembly and photoreduction is reported. The mesoporous materials were characterized by thermogravimetric (TGA)/differential
scanning calorimetric (DSC), low angle and wide angle X-ray diffraction (XRD), transmission electron microscope (TEM), high-resolution
transmission electron microscopy (HRTEM) and N2 adsorption–desorption. The photocatalytic activities of the prepared mesoporous materials were evaluated by the photodegradation
of methyl orange. 相似文献