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81.
p-Styrenesulfonate derivatives having cycloaliphatic epoxide in a molecule, were synthesized. Oligomerization of the monomers and co-polymerization of the novel monomers with tert-butyl methacrylate were carried out. When the polymer films containing a photoacid generator (PAG) were irradiated, they became insoluble in solvents. The insoluble films became soluble in water on baking at 120-200 °C. The insolubilization and redissolution profiles were strongly affected by the structure of the monomer, irradiation and baking conditions, and a type of PAG used. The reaction mechanism was studied by TGA analysis and FT-IR spectroscopy. 相似文献
82.
Hiroshi Kominami Jun-ichi Kato Shin-ya Murakami Yoshinori Ishii Masaaki Kohno Kei-ichi Yabutani Takuhei Yamamoto Yoshiya Kera Masashi Inoue Tomoyuki Inui Bunsho Ohtani 《Catalysis Today》2003,84(3-4):181-189
Thermal treatment of titanium(IV) butoxide dissolved in 2-butanol at 573 K under autogenous pressure (alcohothermal treatment) yielded microcrystalline anatase-type titanium(IV) oxide (TiO2). Thermal treatment of oxobis(2,4-pentanedionato-O,O′)titanium (TiO(acac)2) in ethylene glycol (EG) in the presence of sodium acetate and a small amount of water at 573 K yielded microcrystalline brookite-type TiO2. Tungsten(VI) oxide (WO3) powders of monoclinic crystal structure with high crystallinity were synthesized by hydrothermal treatment (HTT), at 523 or 573 K, of aqueous tungstic acid (H2WO4) solutions prepared from sodium tungstate by ion-exchange (IE) with a proton-type resin. Anatase and brookite TiO2 products were calcined at various temperatures and then used for photocatalytic mineralization of acetic acid in aqueous solutions under aerated conditions and dehydrogenation of 2-propanol under deaerated conditions. Almost all the anatase-type TiO2 samples showed the activities more than twice higher than those of representative active photocatalysts, Degussa P-25 and Ishihara ST-01 in both reactions. A brookite sample with improved crystallinity and sufficient surface area obtained by calcination at 973 K exhibited the hydrogen evolution rate almost equal to P-25. HTT WO3 powders with various physical properties were used as photocatalyst for evolution of oxygen (O2) from an aqueous silver sulfate solution. WO3 powder of high crystallinity, e.g., IE-HTT-WO3 synthesized at 573 K, gave much higher O2 yield than commercially available WO3 samples. 相似文献
83.
Quantum Property Testing of Group Solvability 总被引:1,自引:0,他引:1
Testing efficiently whether a finite set Γ with a binary operation ⋅ over it, given as an oracle, is a group is a well-known
open problem in the field of property testing. Recently, Friedl, Ivanyos and Santha have made a significant step in the direction
of solving this problem by showing that it is possible to test efficiently whether the input (Γ,⋅) is an abelian group or is far, with respect to some distance, from any abelian group. In this paper, we make a step further and construct
an efficient quantum algorithm that tests whether (Γ,⋅) is a solvable group, or is far from any solvable group. More precisely, the number of queries used by our algorithm is polylogarithmic
in the size of the set Γ. 相似文献
84.
Noboru Yamashita Satoshi Izumikawa Akira Takagi Haruyuki Arakawa Tatsuyoshi Wakasawa Atsushi Maruyama 《Journal of materials science. Materials in medicine》2009,20(6):1299-1305
A novel method for the preparation of gelatin sponge millispheres (GSMs) for biomaterials such as embolic agents and cell
scaffolds was developed using an air-in-water-in-oil-type emulsion. The droplets, consisting of a foamy gelatin suspension
in caprylic triglyceride, were gelled and rinsed with isopropanol. Sonication and depressurization were used during the rinsing
process to create interconnected pores. GSMs cross-links created over 4 h at 155°C without any agent were insoluble and had
short and long diameters of 1.1 ± 0.2 mm and 1.3 ± 0.2 mm, respectively. The residual isopropanol and caprylic triglyceride
were <0.05% (w/w) and <1% (w/w) respectively. The level of bacterial endotoxins in the extracts was below 0.025 EU/ml, and
no bacterial or fungal growth was found during sterility testing. The GSMs produced using this method were considered to meet
the basic requirements of embolic agents. 相似文献
85.
Kitsakorn Locharoenrat Haruyuki Sano 《Science and Technology of Advanced Materials》2007,8(4):277-281
We report on the experimental observation of surface plasmon resonance in Cu nanowires fabricated by shadow deposition method. When the incident light is polarized perpendicular to the wire axes, plasmon maxima appeared at about 2.3 eV in the absorption spectra. Plasmon resonance appeared at lower photon energy when the incident light is polarized parallel to the wire axes. Resonance peaks move to lower energy when the nanowire widths are increased. We have found that finite-difference time-domain (FDTD) simulation gives better results than Maxwell-Garnett model in explaining the relation between the light polarization and the energies of the observed absorption maxima. 相似文献
86.
Takashi Watanabe Hiroko Ikeda Kazuo Masaki Tsutomu Fujii Haruyuki Iefuji 《Journal of Bioscience and Bioengineering》2009,108(3):225-230
Phosphohydrolysis of organic phosphorus compounds by acid phosphatases (EC 3.1.3.1 and EC 3.1.3.2) is an important method for efficient removal of phosphorus from high concentration organic wastewater. Another important method is supplementation of animal feed with phytase (EC 3.1.3.8 and EC 3.1.3.26), which improves the availability of phytate-phosphates (phosphate that are hydrolyzed by phytases), making it possible to add less phosphate to animal feed and resulting in the excretion of less phosphorus by the animals. In the present study, we purified a novel phytase from the wastewater treatment yeast Hansenula fabianii J640 (Hfphytase), cloned the 1456 bp open reading frame (ORF) encoding Hfphytase, and characterized Hfphytase. The molecular weight of Hfphytase after deglycosylation by PNGaseF was 49 kDa. The optimal pH and temperature for enzyme activity were 4.5 and 50 °C, respectively. Hfphytase exhibits 40% identity with Debaryomyces castellii phytase, 37% identity with Aspergillus niger PhyB, and 34% identity with Saccharomyces cerevisiae Pho5p. Recombinant Hfphytase was transformed and expressed in Pichia pastoris. The yield was 23 g/l by jar fermenter cultivation. The marked phosphohydrolysis activity exhibited by Hfphytase on six substrates (pNP-P, sodium phytate, glucose-1 phosphate, glucose-6 phosphate, α-glycerophosphate and β-glycerophosphate) indicated that it is a non-specific acid phosphatase. 相似文献
87.
Norihiko L. Okamoto Jung-Hwan Kim Katsushi Tanaka Haruyuki Inui 《Acta Materialia》2006,54(20):5519-5528
The crystal structures of type-I and type-III clathrate compounds in the Ba–Ga–Ge system have been investigated by synchrotron X-ray powder diffraction at room temperature with single- and split-site models to describe thermal vibration of the Ba atoms that are believed to ‘rattle’ in the encapsulating cages. The split-site model is verified to be more plausible when judged from the changes of the extent of thermal vibration of the Ba atoms and the shape changes of the encapsulating cages with the Ga content for both types of compound. When described with the split-site model, the value of lattice thermal conductivity at room temperature decreases with increasing split distance of the Ba atom site for both types of compound, indicating that the split distance can be used as a parameter to describe the extent of thermal vibration (rattling motion) of the Ba guest atoms in the encapsulating cages. 相似文献
88.
Nobuhiko Mukai Kazuo Masaki Tsutomu Fujii Makoto Kawamukai Haruyuki Iefuji 《Journal of Bioscience and Bioengineering》2010,109(6):564-569
The volatile phenols, to which Saccharomyces cerevisiae converts from phenylacrylic acids including ferulic acid, p-coumaric acid, and cinnamic acid, generate off-flavors in alcoholic beverages such as beer and wine. Using gene disruptants, transformants and cell-free extracts of these strains, we have verified that the adjacent PAD1 (phenylacrylic acid decarboxylase, YDR538W) and FDC1 (ferulic acid decarboxylase, YDR539W) genes are essential for the decarboxylation of phenylacrylic acids in S. cerevisiae. Pad1p and Fdc1p are homologous with UbiX and UbiD, respectively, in the ubiquinone synthetic pathway of Escherichia coli. However, ubiquinone was detected quantitatively in all of the yeast single-deletion mutants, Δpad1, Δfdc1, and double-deletion mutant, Δpad1Δfdc1. 相似文献
89.
Crosslinking and ozone degradation of thermosetting resins based on maleic anhydride/diene copolymer and polyfunctional alcohols
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Crosslinking and de‐crosslinking reactions of an alternating copolymer of maleic anhydride (MAn) and 2,4‐dimethyl‐1,3‐pentadiene (DMPD) by thermal curing with polyfunctional alcohols as the crosslinkers and subsequent ozone degradation are reported in this article. The ring‐opening reaction of an anhydride group by polyfunctional alcohols produces network polymers with an ester linkage. The rate of crosslinking reaction depends on the curing conditions, i.e. the structure of the used alcohols and the curing temperature and time. The crosslinking density of the alcohol‐cured copolymers is low due to a slow reaction between the anhydride and hydroxy groups, being different from the corresponding epoxy‐cured copolymer with a dense network structure reported in a previous article. The insoluble resins are readily de‐crosslinked and solubilized by ozone degradation. The polymer surface modification by ozone is also investigated. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42763. 相似文献
90.
Novel poly(aryl ether) type dendrimers having photo-cross-linking and thermal de-cross-linking properties were synthesized by a convergent method. A protected A2B monomer, 1-allyloxy-3,5-bis(bromomethyl)benzene, was newly prepared for the dendrimer synthesis. Palladium-catalyzed deprotection of an allyl group proceeded in high yields. The films of dendrimers containing a photoacid generator (PAG) became insoluble in solvents on irradiation. The irradiated films became soluble in solvents after baking at 120-200 °C. The insolubilization and redissolution profiles were strongly affected by irradiation and baking conditions and the generation of the dendrimers. A reaction pathway was studied by TGA and DTA analysis and FT-IR spectroscopy. 相似文献