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91.
Takaaki Yamamoto Jibin Alex Abraham Shigeki Mori Motoki Toganoh Soji Shimizu Masatoshi Ishida Hiroyuki Furuta 《化学:亚洲杂志》2020,15(6):748-752
Incorporating tungsten into the N3 core of a N‐fused porphyrin (NFP; 1 ) affords high‐valent tungsten(VI)‐NFP complexes, WClO2‐1 and 21‐chlorinated WClO2‐3 . The X‐ray structure of WClO2‐1 reveals a distorted octahedral geometry with sitting atop metal coordination. The absorption spectrum of WClO2‐1 displays bathochromically shifted Q‐like bands beyond 1000 nm, indicating an inherently narrow HOMO‐LUMO energy gap. DFT calculations show that the degeneracy of the LUMO and LUMO+1 pair of 1 is significantly resolved by the tungsten(VI) coordination. Conclusively, magnetic circular dichroism (MCD) spectroscopy and cyclic voltammetry provide a rationale for the narrow HOMO‐LUMO energy gap in the “16‐electron” d0 tungsten(VI)‐NFP complexes. 相似文献
92.
Toshihide Matsuno Sachie Horii Takanobu Sato Yoshiki Matsumiya Motoki Kubo 《Applied biochemistry and biotechnology》2013,169(3):795-809
Accumulations of inorganic nitrogen (NH4 +, NO2 ?, and NO3 ?) were analyzed to evaluate the nitrogen circulation activity in 76 agricultural soils. Accumulation of NH4 + was observed, and the reaction of NH4 +?→?NO2 ? appeared to be slower than that of NO2 ??→?NO3 ? in agricultural soil. Two autotrophic and five heterotrophic ammonia-oxidizing bacteria (AOB) were isolated and identified from the soils, and the ammonia-oxidizing activities of the autotrophic AOB were 1.0?×?103–1.0?×?106 times higher than those of heterotrophic AOB. The relationship between AOB number, soil bacterial number, and ammonia-oxidizing activity was investigated with 30 agricultural soils. The ratio of autotrophic AOB number was 0.00032–0.26 % of the total soil bacterial number. The soil samples rich in autotrophic AOB (>1.0?×?104 cells/g soil) had a high nitrogen circulation activity, and additionally, the nitrogen circulation in the agricultural soil was improved by controlling the autotrophic AOBs. 相似文献
93.
Yuki Fukuhara Sachie Horii Toshihide Matsuno Yoshiki Matsumiya Masaki Mukai Motoki Kubo 《Applied biochemistry and biotechnology》2013,170(2):329-339
A real-time PCR quantification method for indigenous hydrocarbon-degrading bacteria (HDB) carrying the alkB gene in the soil environment was developed to investigate their distribution in soil. The detection limit of indigenous HDB by the method was 1?×?106 cells/g-soil. The indigenous HDB were widely distributed throughout the soil environment and ranged from 3.7?×?107 to 5.0?×?108 cells/g-soil, and the ratio to total bacteria was 0.1–4.3 %. The dynamics of total bacteria, indigenous HDB, and Rhodococcus erythropolis NDKK6 (carrying alkB R2) during bioremediation were analyzed. During bioremediation with an inorganic nutrient treatment, the numbers of these bacteria were slightly increased. The numbers of HDB (both indigenous bacteria and strain NDKK6) were gradually decreased from the middle stage of bioremediation. Meanwhile, the numbers of these bacteria were highly increased and were maintained during bioremediation with an organic nutrient. The organic treatment led to activation of not only the soil bacteria but also the HDB, so an efficient bioremediation was carried out. 相似文献
94.
The effect of self-pumped phase conjugation (SPPC) feedback from a Ce:BaTiO3 crystal on the lasing spectrum of a commercial laser diode was experimentally investigated, and dependence of the spectrum on the length and reflectivity of the external SPPC cavity was studied. Experimental results showed the optimum reflectivity of the external cavity to be 0.2% for our experimental setup. 相似文献
95.
Hirotaka Matsuura Takuya Hasegawa Hitomi Nagata Kohei Takatani Motoki Asano Akihide Itoh Hiroki Haraguchi 《Analytical sciences》2003,19(1):117-121
The speciation of diverse elements in salmon egg cell cytoplasm was performed by a surfactant-mediated HPLC/ICP-MS hyphenated system. In the present experiment, an ODS column coated with CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate), which is a zwitterionic bile acid derivative, was employed as a surfactant-mediated separation column, and ICP-MS was used as an element-selective detector. The present surfactant-mediated HPLC allowed us to separate large and small molecules within 10 min; large molecules, such as proteins, were eluted within 2.5 min, while small molecules were eluted after 2.5 min, but within 10 min. In the present experiment, Fe, Cu, and Zn in egg cell cytoplasm were observed mostly in species with large molecular weights, indicating that these elements are contained as metalloproteins or metalloenzymes in egg cell cytoplasm. On the contrary, it was found that P, S, Mo, and halogens in egg cell cytoplasm were contained as small molecules or inorganic ions. The major species of P in egg cell cytoplasm was identified as the phosphate ion (PO4(3-)). Molybdenum, Cl, and Br in egg cell cytoplasm were molybdate (MoO4(2-), chloride (Cl-), and bromide (Br-) ions, respectively. 相似文献
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The intermolecular C-H cross-coupling between aromatic ethers has been achieved for the first time using perfluorinated hypervalent iodine(III) compounds as extreme single-electron-transfer (SET) oxidants. The demonstrations of this specific coupling could provide a direct route to valuable oxygenated mixed naphthalene-benzene biaryls 3 only, without formation of other biaryl-derived byproducts. 相似文献
100.
For improving sound insulation of a double leaf dry partition, each leaf is often consisted of more than one panel. Previous study on predicting a transmission loss of double leaf partition, treats with the leaf varied just two kinds of panels and restricted to a leaf having same kind and same thickness. These restrictions are unfit for variety of current building materials and constructions. This study makes a prediction formula for a transmission loss of the double leaf partition with laminated leaves by a theoretical analysis and an experiment, and will discuss the predicted value with measured value in previous studies and catalogs. 相似文献