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31.
Ze‐Hua Liu Takeshi Hashimoto Yoichi Okumura Yoshinori Kanjo Satoshi Mizutani 《洁净——土壤、空气、水》2010,38(2):181-188
A solid‐phase extraction (SPE)‐gas chromatography (GC)‐mass spectrometry (MS) analytical method was developed for the simultaneous analysis of natural free estrogens and their conjugates in wastewater samples. Natural free estrogens and their conjugates in wastewater were successfully separated by the oasis hydrophilic‐lipophilic balance solid phase extraction (Oasis HLB SPE) method, and the conjugates were initially enzyme hydrolyzed by β‐glucuronidase or arylsulfatase from Helix pomatia prior to derivatization. N‐methyl‐N‐(tert‐butyldimethylsilyl)trifluoroacetamide (MTBSTFA) plus 1% tert‐butyldimetheylchlorosilane (TBDMCS) was chosen as the derivatization reagent, and the most appropriate conditions of derivatization were determined to be at 95°C for 90 min. The recovery ratios of nine target chemicals were determined by spiking them in 1 L of ultra‐purified water or the influent of a wastewater treatment plant (WWTP). The recovery ratios of six out of nine for the analytes ranged from 73.3–114.9% with relative standard deviations (RSD) from 1.6–19.9%. The established method was successfully applied to environmental wastewater samples which were collected from one municipal wastewater treatment plant (WWTP) in Osaka, Japan, for the determination of natural free estrogens and their conjugates. In the influent sample, E1, E2, E1‐3S, E3‐3S, and E1‐3G were detected at concentrations of 16.6, 9.6, 8.2, 21.9, and 3.2 ng L–1, respectively. However, only E1 was detected at a high concentration of 44 ng L–1 in the effluent sample, suggesting that it is the dominant natural free estrogen in the effluent. 相似文献
32.
Konishi Hisahiro Manabu Kato Susumu Sasaki Yoshisada Takizawa Hitoshi Mizutani 《Journal of Earth System Science》2005,114(6):771-775
SELENE (Selenological and Engineering Explorer) project started as a joint mission of the former ISAS (Institute of Space
and Astronautical Science) and the former NASDA (National Space Development Agency: the two organizations were merged into
JAXA in 2002) of Japan in 1998. The launch target is rescheduled for 2006 due to delay of completion of launch vehicle, H-IIA.
The SELENE project is now under a sustained design phase. The flight model components were manufactured, and the interface
tests between the bus-system and the mission instruments were completed by the end of March 2004. The functional checks and
calibration for the flight model components are being carried out at present. From the beginning of 2005, the final assembly
tests will start. 相似文献