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排序方式: 共有155条查询结果,搜索用时 31 毫秒
1.
Pyridine-based, structurally isomeric two macrocyclic compounds displayed a remarkably different complexation nature. The cage-type compound has an ideal structure for spherical cations, especially for the NH4+ ion, but the reaction with some transition metals and Ln3+ produced its protonated species. On the other hand, its isomer formed complexes with alkali metals and lanthanides (1:1) and also with transition metals. Some structures of the complexes were clarified by crystallographic analyses. 相似文献
2.
Tsuyoshi Miura Satoshi Tsujino Kohtaro Goto Midori Noguchi Manabu Node Nobuyuki Imai 《Tetrahedron》2005,61(27):6518-6526
The use of the bisfluorous chain-type propanoyl (Bfp) group as a fluorous protective group made it possible to rapidly synthesize the Gb2 and Gb3 oligosaccharide derivatives by a simple fluorous-organic extraction purification. Furthermore, the fluorescence-labeled Gb2 and Gb3 oligosaccharides were prepared as a potential Vero Toxins detecting reagent. 相似文献
3.
Manabu Tsujino Tetsuhiko Isobe Mamoru Senna 《Journal of Sol-Gel Science and Technology》2000,19(1-3):785-789
A tetraethoxysilane (TEOS)-derived sol aged for 0 h–6 h at room temperature was mixed with a polyurethane (PU) matrix. A composite of silk fibroin (SF) powders and acrylamide (AAm) was dispersed in the sol-PU mixture and dried isothermally at temperatures between 25°C and 120°C to obtain composite films. Three competitive reactions take place, i.e., those between silica-silica, SF-PU and silica-organic phases, during formation of the composite films. These reactions determine the properties such as morphology and homogeneity of the composite films. IR absorption bands for amide groups (–CONH–), C=O (amide I, 1730 cm–1) and N–H (amide II, 1530 cm–1) become larger with decreasing aging time of TEOS-derived sol, or increasing drying temperature. DTA exothermic peak due to the thermal decomposition of SF-AAm composite, on the composite films prepared from the 0 h-aged sol or dried at more than 50°C, shifts toward higher temperature by 44 K or more than 63 K respectively, as compared to the SF-AAm composite. Shorter aging time of TEOS-derived sol and higher drying temperature increased the extent of dispersibility, among SF-AAm composite, PU and silica, to bring a composite film more homogeneous. 相似文献
4.
5.
Carbon dioxide fixation by microalgae photosynthesis using actual flue gas discharged from a boiler 总被引:2,自引:0,他引:2
Matsumoto Hiroyo Shioji Norio Hamasaki Akihiro Ikuta Yoshiaki Fukuda Yoshinori Sato Minoru Endo Noriyoshi Tsukamoto Toshiaki 《Applied biochemistry and biotechnology》1995,(1):681-692
To mitigate CO2 discharged from thermal power plants, studies on CO2 fixation by the photosynthesis of microalgae using actual exhaust gas have been carried out. The results are as follows.
相似文献
1. | A method is proposed for evaluating the maximum photosynthesis rate in the raceway cultivator using only the algal physical properties; |
2. | Outdoor cultivation tests taking actual flue gas were performed with no trouble or break throughout 1 yr using the strain collected in the test; |
3. | The produced microalgae is effective as solid fuel; and |
4. | The feasibility studies of this system were performed. The system required large land area, but the area is smaller than that required for other biomass systems, such as tree farms. |
6.
Normal hematopoietic progenitor cells from 129S6/SvEv mice are substantially less sensitive to Merocyanine 540 (MC540)-mediated photodynamic therapy (PDT) than hematopoietic progenitors from sex- and age-matched C57BL/6 mice. When exposed to a combination of MC540 and light commonly used for the extracorporeal purging of hematopoietic stem cells, granulocyte/macrophage progenitors (CFU-GM) from C57BL/6 mice are depleted 7.9-fold whereas CFU-GM from 129S6/SvEv and (C57BL/6 x 129S6/SvEv) F1 mice are depleted 1.4- and 2-fold, respectively. The same rank order of sensitivity is also found with regard to unipotent progenitors of granulocytes and macrophages and with regard to early and late erythroid progenitors. The resistance of hematopoietic progenitors from 129S6/SvEv mice to MC540-PDT appears to be the result of reduced dye binding rather than the result of high levels of intracellular glutathione. These findings have practical implications for the design of preclinical tests of PDT in animal models. They may also provide a useful tool for future investigations into the molecular determinants of sensitivity to MC540-PDT. 相似文献
7.
8.
Ultrasonic butt welding of aluminum,aluminum alloy and stainless steel plate specimens 总被引:3,自引:0,他引:3
Tsujino J Hidai K Hasegawa A Kanai R Matsuura H Matsushima K Ueoka T 《Ultrasonics》2002,40(1-8):371-374
Welding characteristics of aluminum, aluminum alloy and stainless steel plate specimens of 6.0 mm thickness by a 15 kHz ultrasonic butt welding system were studied. There are no detailed welding condition data of these specimens although the joining of these materials are required due to anticorrosive and high strength characteristics for not only large specimens but small electronic parts especially. These specimens of 6.0 mm thickness were welded end to end using a 15 kHz ultrasonic butt welding equipment with a vibration source using eight bolt-clamped Langevin type PZT transducers and a 50 kW static induction thyristor power amplifier. The stainless steel plate specimens electrolytically polished were joined with welding strength almost equal to the material strength under rather large vibration amplitude of 25 microm (peak-to-zero value), static pressure 70 MPa and welding time of 1.0-3.0 s. The hardness of stainless steel specimen adjacent to a welding surface increased about 20% by ultrasonic vibration. 相似文献
9.
The absorption maxima of the fluorescence spectra of the berberine series alkaloids are broadly distributed between 360 and 560 mμ. The fluorescence spectra of most substances of this series are very monotonous one having a single peak, the spectra of tetrahydrocoptisine and tetrahydroepiberberine are quite exceptional and consist of two wavy bands. The introduction of the auxochrome group into the molecule of “proto” compounds causes the decreasing of the fluorescence intensity and this effect is strongest in case of transition from protoberberine to berberine. That, tetrahydropalmatine does not show the distinct fluorescence spectrum band is the only incomprehensible fact. 相似文献
10.
Numerical calculations of eigenfunctions and the participation ratio P are carried out for a two-dimensional square lattice where the site diagonal and/or off-diagonal matrix elements of a one-electron Hamiltonian are disordered. We show that, for purely off-diagonal disorder, states near the centre of the band will never be localized but states in the wings of the band are localized. We also see that the combined effects of diagonal and off-diagonal disorder yield several interesting results. Moreover, we confirm that, as suggested by Economou and Antoniou, the mobility-edge surface takes a bottle-neck shape in the three-dimensional space defined by energy E, the degree of diagonal randomness Γ and the degree of off-diagonal randomness V1. 相似文献