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71.
72.
Yoshiaki Nakanishi Michiaki Sumita Kaoru Yumita Takashi Yamada Takaharu Honjo 《Analytical sciences》2004,20(1):73-78
Alga as Achnanthes minutissima among diatoms is a widely adaptable taxon on the state of an aquatic environment. In this study, it was found that diatom had a specific tolerance to heavy metals (Cu, Zn, Pb, and Cd etc.) in river water samples, because the diatom assemblage consisted of almost only Achnanthes minutissima in Kakehashi river and Godani river, which were polluted with waste water from Ogoya copper mine. The relationship between the concentrations of heavy metals (Cu, Zn, Pb and Cd) in river water and the attached substances (algae and silt etc.) and the relative abundances of diatom taxa were investigated in detail. The results indicated that the higher is the concentration of heavy metals in the river environment, the higher is only the relative abundances of Achnanthes minutissima. Thus, the taxon can be used as a bioindicator of heavy metal pollution. The relative rates of toxic chemical forms of copper in algae were 61 - 92% in the attached substances and 49-70% in the sediment on the river bed, respectively. Therefore, it was found that diatom as Achnanthes minutissima had a tolerance to heavy metals in river water, being able to live in such an environment. Since the water treated with calcium hydroxide from the deposition reservoir of Ogoya mine enters in Godani river, the river is polluted by heavy metals (Cu, Zn, Pb and Cd etc.). From the viewpoint of both biological and chemical analyses, Godani river is still polluted with heavy metals, because their concentrations in the river samples were very high. On the other hand, in Kakehashi river, the concentrations of heavy metals were very low and the distributions of some diatoms appeared in an unpolluted Nishimata river were observed. Therefore, Kakehashi river seems to be considerably recovered from heavy-metal pollution after closing the Ogoya mine. 相似文献
73.
Naoyuki Kinoshita Kazunari Domen Ken-ichi Aika Takaharu Onishi 《Applied Surface Science》1984,18(3):342-344
The infrared band of dinitrogen species adsorbed on a Co/Al2O3 catalyst was observed at 2214 cm-1, which shifted in the presence of adsorbed and gaseous hydrogen. 相似文献
74.
Naoki Hirayama Noriko Sugisaka Junko Taga Syunichi Oshima Takaharu Honjo 《Analytical sciences》2003,19(2):321-324
"Substituent on benzenesulfonyl group" effect of 8-benzenesulfonamidoquinoline [N-(8-quinolyl)benzenesulfonamide, Hbsq] as bidentate chelate extractant for divalent metal cations was investigated with using Hbsq and its eight derivatives. Introduction of electron-withdrawing substituent on the benzenesulfonyl group in Hbsq enhanced the extractability that originated from its inductive effect. Furthermore, a bulky substituent on an ortho-position of the benzenesulfonyl group resulted in no steric effect in extraction, whereas the existence of two substituents on each ortho-position caused lower extraction performance due to steric hindrance. 相似文献
75.
Takaharu Otsuka 《Hyperfine Interactions》1992,74(1-4):93-111
76.
77.
78.
Tomoji Kawai Mitsuyuki Soma Yoshio Matsumoto Takaharu Onishi Kenzi Tamaru 《Chemical physics letters》1976,37(2):378-382
X-ray photoelectron (XPS) and ultraviolet photoelectron (UPS) spectroscopic techniques have been employed to study the chemisorption of various molecules over metal-phthalocyanines (MePc). It was revealed that pyridine is adsorbed on the Fe atom in FePc which is accompanied by a change in the spin state without transfer of net electron charge, while HCOOH is heterolytically dissociated, the formate ion staying on the central metal atom and the proton on the bridge N atom of the porphyrin ring. H2O on MgPc behaved like HCOOH, with a proton being adsorbed at a bridge N atom. On the basis of these results, the catalytic decomposition of HCOOH and adsorption of pyridine on MePc are discussed. 相似文献
79.
Abstract— On treatment with 8-methoxypsoralen plus near UV light, an excisionless ( uvrB- ) strain of Escherichia coli showed about 3– and 10 times higher sensitivities to killing and mutation, respectively, than its parental strain. On re-irradiation with near UV in the absence of unbound psoralen, the uvrB- strain pretreated with psoralen plus near UV showed a decrease in both survival and mutation. After treatment with psoralen plus near UV, re-irradiation of T7 DNA in the absence of unbound psoralen caused an increase in the cross-linked fraction with an equivalent decrease in the non-cross-linked fraction. From these and previous results, we conclude that monoadducts produced by treatment with psoralen plus near UV are converted to cross-links by further irradiation and that, in E. coli , monoadducts are responsible for the mutation induced by psoralen-plus-light whereas cross-links are the major cause of its lethal action. 相似文献
80.
Redox‐Switchable 20π‐, 19π‐, and 18π‐Electron 5,10,15,20‐Tetraaryl‐5,15‐diazaporphyrinoid Nickel(II) Complexes 下载免费PDF全文
Takaharu Satoh Prof. Dr. Mao Minoura Prof. Dr. Haruyuki Nakano Prof. Dr. Ko Furukawa Prof. Dr. Yoshihiro Matano 《Angewandte Chemie (International ed. in English)》2016,55(6):2235-2238
The first examples of air‐stable 20π‐electron 5,10,15,20‐tetraaryl‐5,15‐diaza‐5,15‐dihydroporphyrins, their 18π‐electron dications, and the 19π‐electron radical cation were prepared through metal‐templated annulation of nickel(II) bis(5‐arylamino‐3‐chloro‐8‐mesityldipyrrin) complexes followed by oxidation. The neutral 20π‐electron derivatives are antiaromatic and the cationic 18π‐electron derivatives are aromatic in terms of the magnetic criterion of aromaticity. The meso N atoms in these diazaporphyrinoids give rise to characteristic redox and optical properties for the compounds that are not typical of isoelectronic 5,10,15,20‐tetraarylporphyrins. 相似文献