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91.
Uzawa H Nishida Y Sasaki K Minoura N Kobayashi K 《Chembiochem : a European journal of chemical biology》2003,4(7):640-647
The substrate specificities of three molluscan sulfatases (E.C. 3.1.6.1; snail, abalone, and limpet origins) were investigated with assorted p-nitrophenyl (pNP) di-O-sulfonated beta-D-galactopyranosides and beta-lactosides [3,6-SO(3) Gal (1), 3',6'-SO(3) Lac (2), 4, 6SO(3) Gal (3), 2,6-SO(3) Gal (4), 3,4-SO(3) Gal (5), and 3,6-SO(3) GalNAc (6); Ac, acetyl; Gal, galactose; Lac, lactose] together with mono-O-sulfonated beta-D-galactopyranoside [pNP 3SO(3)-Gal (7)] and tri-O-sulfonated alpha-D-galactopyranoside [2,3,6-SO(3)-alpha-Gal (11)]. Some notable differences between the substrate specificity of the three sulfatases were disclosed; snail sulfatase hydrolyzed the 3O- and 2O-sulfo groups of 1 and 4, respectively, to afford 6SO(3) Gal (9) in high yields, while the abalone enzyme did not act on 4. Only the limpet enzyme could cleave the 3O-sulfo groups of 7 to give pNP beta-galactoside. In contrast, every enzyme could utilize 11 as a good substrate to afford a mixture of 6SO(3)-alpha-Gal (13) and 2,6-SO(3) alpha-Gal (12). None of the enzymes could cleave the O-sulfo groups of 5 and 6, which indicates that a primary 6O-sulfo group tends to promote the enzymatic hydrolysis of O-sulfo groups at the secondary positions. 相似文献
92.
N‐Isopropylacrylamide/acrylic acid copolymer hydrogels were synthesized with ultrasound. The thermoresponsive phase behaviors of gels synthesized with ultrasound (US gels) were investigated and compared with those of gels synthesized in the absence of ultrasound (FR gels). The US gels showed thermoresponsive swelling behavior with a large hysteresis over a wide range of temperatures around its phase‐transition temperature. The hysteresis became larger with an increasing copolymerized acrylic acid content. The US gels were also characterized from the viewpoint of chemical, hydration, and macroscopic physical structures. Little difference was observed in the chemical and hydration structures of the FR gels and US gels. The macroscopic physical structure of the US gels was, however, distinct from that of the FR gels. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2449–2452, 2003 相似文献
93.
Shoichiro Yamamoto Tadahide Kurokawa Masashi Sekino Motoshige Yasuike Kenji Saitoh 《International journal of molecular sciences》2013,14(11):23153-23159
We developed tetranucleotide-repeat microsatellite markers for the masu salmon (Oncorhynchus masou) complex. 454 pyrosequencing was used to discover repeat motifs, and seven polymorphic microsatellite-primer sets were identified. The number of alleles detected at each locus ranged from four to 24 and the expected heterozygosity varied from 0.57 to 0.92. Cross-subspecies amplification for O. m. masou, O. m. ishikawae and O. m. subsp. was successful. These microsatellites can be utilized in studies of genetic structure, genetic diversity, and intra- and inter-subspecific hybridization, making a contribution to conservation and management of the Oncorhynchus masou complex. 相似文献
94.
Itaru Natori Shizue Natori Anna Kanasashi Kosuke Tsuchiya Kenji Ogino 《Reactive and Functional Polymers》2013,73(1):200-206
The synthesis of tetraphenylporphyrin (H2TPP)-end-functionalized poly(p-phenylene) (H2TPP-PPP) as a leaf-green-colored soluble semiconducting polymer with a well-controlled and defined polymer chain structure was achieved for the first time. Chloromethyl-end-functionalized poly(1,3-cyclohexadiene) (CM-PCHD) was prepared by the living anionic polymerization of 1,3-cyclohexadiene and the post-polymerization reaction of poly(1,3-cyclohexadienyl)lithium and chloro(chloromethyl)dimethylsilane. H2TPP-end-functionalized PCHD (H2TPP-PCHD) was then prepared by the addition of 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin to CM-PCHD. The dehydrogenation of H2TPP-PCHD with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone was performed under ultrasonic irradiation, and H2TPP-PPP was obtained as a target polymer in almost quantitative yield. The –Si(CH3)2–CH2–O– bond in H2TPP-PPP effectively inhibited the coordination of the H2TPP end-group onto the PPP moiety, and the aggregation of H2TPP-PPP with the accumulation of the H2TPP end-group was formed. H2TPP-PPP exhibited a leaf-green color and had a very broad absorption band overlapping the visible-light region, similar to chlorophyll a. 相似文献
95.
The measurement of ozone concentration based on the visible photo absorption method is investigated. An LED having an emission peak at 609 nm and a photo diode sensitive at visible light frequencies are used as the light source and the photo detector, respectively. The transmittance is measured as a function of ozone concentration, which is in reasonable agreement with the Beer–Lambert relationship. The effective absorption cross-section can therefore be estimated from the fitting procedure. The concentrations determined by both the UV and visible photo absorptions agree well with each other in the range from 7.1 to 68.4 g/m3(N). The relative error in these concentrations is discussed on the basis of the Twyman–Lothian curve. The ozone measurement for the air-fed ozone generation is also investigated. The effect of photo absorption due to NOx species is unavoidable. The present results provide useful data if the ozone measurement based on the visible photo absorption method is applied to ozone monitoring instruments or used for laboratory experiments. 相似文献
96.
97.
Masahiro Kato Kazuaki Nakagawa Kenji Essaki Yukishige Maezawa Shin Takeda Ryosuke Kogo Yoshikazu Hagiwara 《International Journal of Applied Ceramic Technology》2005,2(6):467-475
We have discovered a series of lithium-containing oxides that immediately react with ambient carbon dioxide (CO2 ) up to 700°C. The products react and return reversibly to the oxides at a temperatures higher than about 700°C. The absorption capacity surpasses that of other CO2 absorbents by a factor of 10. Utilizing these absorbents, the possibility of a CO2 separation system that operates at around 500°C is proposed. It is generally believed that a CO2 separation process operable at temperatures higher than 500°C has the special benefit of a small energy penalty. Moreover, the absorption also proceeds at ambient temperature in the atmospheric environment. This property offers the possibility of many other applications, such as air cleaners or cartridges. Therefore, we think these materials have the potential to make a valuable contribution to the realization of CO2 emission control. 相似文献
98.
Kenji Asami Qianwen Zhang Xiaohong Li Sachio Asaoka Kaoru Fujimoto 《Catalysis Today》2005,106(1-4):247-251
Efficient conversion of dimethyl ether (DME) into liquefied petroleum gas (LPG) with a hybrid catalyst is a novel method for semi-indirect synthesis of LPG fuel from syngas. The hybrid catalysts consisting of zeolite and hydrogenation catalyst were investigated in a fixed bed reactor. Experimental results demonstrated that the hybrid catalyst consisting of (Pd/SiO2) and USY efficiently converted DME into LPG and restrained decomposition of DME into CO and H2. With that catalyst, the one through conversion of DME reached about 100%, almost no CO and CO2 were produced and selectivity for LPG was more than 65%. 相似文献
99.
The infrared chemiluminescence spectra of CO2 formed during steady-state CO+NO reaction over Pd(110) indicated that the temperature of the bending vibrational mode was much higher than that of the antisymmetric one at higher surface temperatures such as 800–850 K. Especially, in the high temperature range, more vibrationally excited CO2 was formed from CO+NO reaction than CO+O2 reaction. On the basis of the result, we propose the model structure of reaction intermediates for CO2 formation in CO+NO reaction, which is different from that in CO+O2 reaction. 相似文献
100.
Kentaro Fujimoto Yoshiyasu Matsumoto Kohki Oikawa Jun-ichi Nomura Yasuyoshi Shimada Shunrou Fujiwara Kazunori Terasaki Masakazu Kobayashi Kenji Yoshida Kuniaki Ogasawara 《International journal of molecular sciences》2016,17(8)
The purpose of the present study was to determine whether cerebral hyperperfusion after revascularization inhibits development of cerebral ischemic lesions due to artery-to-artery emboli during exposure of the carotid arteries in carotid endarterectomy (CEA). In patients undergoing CEA for internal carotid artery stenosis (≥70%), cerebral blood flow (CBF) was measured using single-photon emission computed tomography (SPECT) before and immediately after CEA. Microembolic signals (MES) were identified using transcranial Doppler during carotid exposure. Diffusion-weighted magnetic resonance imaging (DWI) was performed within 24 h after surgery. Of 32 patients with a combination of reduced cerebrovascular reactivity to acetazolamide on preoperative brain perfusion SPECT and MES during carotid exposure, 14 (44%) showed cerebral hyperperfusion (defined as postoperative CBF increase ≥100% compared with preoperative values), and 16 (50%) developed DWI-characterized postoperative cerebral ischemic lesions. Postoperative cerebral hyperperfusion was significantly associated with the absence of DWI-characterized postoperative cerebral ischemic lesions (95% confidence interval, 0.001–0.179; p = 0.0009). These data suggest that cerebral hyperperfusion after revascularization inhibits development of cerebral ischemic lesions due to artery-to-artery emboli during carotid exposure in CEA, supporting the “impaired clearance of emboli” concept. Blood pressure elevation following carotid declamping would be effective when embolism not accompanied by cerebral hyperperfusion occurs during CEA. 相似文献