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91.
Water-soluble cobalt porphyrin 1Co and imidazole ligand 2 were synthesized. 1Co binds dioxygen in the presence of imidazole ligand 2 in aqueous solution. The formation of the oxygen adduct 2-1Co(O(2)) was studied using UV-vis and EPR spectroscopy. The impact of pH on the kinetic stability of the oxygen adduct was examined. 相似文献
92.
A series of carbon-covered titania (CCT) were prepared via pyrolysis of sucrose highly dispersed on titania surface in flowing
N2. The samples were characterized by XRD, BET, DTA-TG, UV—Vis, and their photocatalytic properties were evaluated with two
model pollutants, methylene blue (MB) and rhodamine B (RB), at room temperature. The effect of carbon content on photocatalytic
activity of the C/TiO2 composite was investigated. It was found that the effect of carbon content is different for different pollutants or different
light sources. For three tested samples, under UV illumination CCT01 has the highest activity for MB photocatalytic degradation,
while in the case of RB, CCT02 is the most active photocatalyst. Under visible light illumination, CCT005 has the highest
activity for both MB and RB photocatalytic degradation.
Translated from Chinese Journal of Catalysis, 2006, 27(1): (in Chinese) 相似文献
93.
Zhang Z Wang J Yuan H Gao Y Liu D Song L Xiang Y Zhao X Liu L Luo S Dou X Mou S Zhou W Xie S 《The journal of physical chemistry. B》2005,109(39):18352-18355
At a low temperature of 450 degrees C, ZnS nanoribbons have been synthesized on Si and KCl substrates by a simple chemical vapor deposition (CVD) method with a two-temperature-zone furnace. Zinc and sulfur powders are used as sources in the different temperature zones. X-ray diffraction (XRD), selected area electron diffraction (SEAD), and transmission electron microscopy (TEM) analysis show that the ZnS nanoribbons are the wurtzite structure, and there are two types-single-crystal and bicrystal nanoribbons. Photoluminescence (PL) spectrum shows that the spectrum mainly includes two parts: a purple emission band centering at about 390 nm and a blue emission band centering at about 445 nm with a weak green shoulder around 510 nm. 相似文献
94.
X. Y. Li G. J. Wang J. G. Sun Y. T. Zheng B. Yan H. T. Xie X. Wang 《Chromatographia》2007,65(1-2):13-18
To support preclinical pharmacokinetic investigation of 1-[4-[2-(4-bromobenzene-sulfonaminoethyl)phenylsufonyl]-3-(trans-4-methylcyclohexyl)urea
(G004), a rapid, sensitive and specific high-performance liquid chromatography–electrospray ionization mass spectrometry (LC–ESI-MS)
method was developed and validated. Glibenclamide was employed as internal standard. After liquid–liquid extraction the analyte
was analyzed on a Kromasil C18 column (150 × 2.0 mm i.d.) with a mobile phase consisted of acetonitrile–water (0.05% acetic acid), 30:70 (v/v). The flow
rate was 0.2 mL min−1. Detection was performed on a quadrupole mass spectrometer using an electrospray ionization interface and the selected-ion
monitoring (SIM) mode. The retention time was about 3.5 and 4.2 min for Glibenclamide and G004, respectively. The assay was
linear over the concentration range of 2.0–500.0 ng mL−1. Extraction Recovery of G004 in rat plasma was more than 87%. The intra- and inter-assay precision was lower than 11.5% (CV).
This validated method was successfully applied to the pharmacokinetics of G004 in rats. 相似文献
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98.
Estimation of an important constant in sieve method 总被引:1,自引:0,他引:1
Xie Sheng-gang 《数学学报(英文版)》1994,10(1):1-3
ζ
k
is one of the most important constant in the sieve methods. This paper gives the relatively accurate lower bound and upper
bound on it, that is,
, wherec=1.22... andk>16. 相似文献
99.
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