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Autori principali:	Wang, Hui, Li, Zheyu, Ding, Jie, Ren, Nanqi
Natura:	Recurso educativo Open Access
Lingua:	en
Pubblicazione:	2021
Soggetti:	Chemistry Science Instruction College Science Graduate Students Science Experiments Scientific Concepts Concept Formation Spectroscopy Science Laboratories Laboratory Experiments Water Pollution Poisoning
Accesso online:	https://eric.ed.gov/?id=EJ1287098
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author	Wang, Hui Li, Zheyu Ding, Jie Ren, Nanqi
author_facet	Wang, Hui Li, Zheyu Ding, Jie Ren, Nanqi Wang, Hui Li, Zheyu Ding, Jie Ren, Nanqi
collection	Education Resources Information Center
contents	Teaching Graduate Students GC-QTOF-MS Operation and Application via an Analytical Chemistry Experiment Wang, Hui Li, Zheyu Ding, Jie Ren, Nanqi Chemistry Science Instruction College Science Graduate Students Science Experiments Scientific Concepts Concept Formation Spectroscopy Science Laboratories Laboratory Experiments Water Pollution Poisoning This experiment combines analytical techniques of solid-phase extraction (SPE) and gas chromatography quadrupole time-of-flight mass spectrometry (GC-QTOF-MS) to determine organochlorine pesticides (OCPs) in river water as a means to develop and improve student understanding of the use of GC-QTOF-MS for qualitative and quantitative analysis. In the classroom, students are presented with the principles and instrumentation of SPE, GC, and QTOF-MS via conventional lectures and question--answer sessions. In the laboratory, they are introduced to the procedure for tuning GC-QTOF-MS and developing a new method, analyzing OCPs in standard solutions to obtain retention times and characteristic ions, employing the mass spectrometry data to conduct library matching, and completing the identification and quantification of OCPs in the river. Additionally, students learn how to deduce the chemical formula of an "unknown" eluent compound by relying on high-resolution mass measurements and isotopic distributions. This method could be applied in the courses of instrumental analysis or environmental analysis. It could be readily adapted to other analytes such as the presence of steroids or other pharmaceuticals.
format	Recurso educativo Open Access
id	eric_EJ1287098
institution	ERIC Institute of Education Sciences
language	en
publishDate	2021
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spellingShingle	Teaching Graduate Students GC-QTOF-MS Operation and Application via an Analytical Chemistry Experiment Wang, Hui Li, Zheyu Ding, Jie Ren, Nanqi Chemistry Science Instruction College Science Graduate Students Science Experiments Scientific Concepts Concept Formation Spectroscopy Science Laboratories Laboratory Experiments Water Pollution Poisoning Teaching Graduate Students GC-QTOF-MS Operation and Application via an Analytical Chemistry Experiment Wang, Hui Li, Zheyu Ding, Jie Ren, Nanqi Chemistry Science Instruction College Science Graduate Students Science Experiments Scientific Concepts Concept Formation Spectroscopy Science Laboratories Laboratory Experiments Water Pollution Poisoning This experiment combines analytical techniques of solid-phase extraction (SPE) and gas chromatography quadrupole time-of-flight mass spectrometry (GC-QTOF-MS) to determine organochlorine pesticides (OCPs) in river water as a means to develop and improve student understanding of the use of GC-QTOF-MS for qualitative and quantitative analysis. In the classroom, students are presented with the principles and instrumentation of SPE, GC, and QTOF-MS via conventional lectures and question--answer sessions. In the laboratory, they are introduced to the procedure for tuning GC-QTOF-MS and developing a new method, analyzing OCPs in standard solutions to obtain retention times and characteristic ions, employing the mass spectrometry data to conduct library matching, and completing the identification and quantification of OCPs in the river. Additionally, students learn how to deduce the chemical formula of an "unknown" eluent compound by relying on high-resolution mass measurements and isotopic distributions. This method could be applied in the courses of instrumental analysis or environmental analysis. It could be readily adapted to other analytes such as the presence of steroids or other pharmaceuticals.
title	Teaching Graduate Students GC-QTOF-MS Operation and Application via an Analytical Chemistry Experiment
topic	Chemistry Science Instruction College Science Graduate Students Science Experiments Scientific Concepts Concept Formation Spectroscopy Science Laboratories Laboratory Experiments Water Pollution Poisoning
url	https://eric.ed.gov/?id=EJ1287098

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// Anecdotal testing Today and Yesterday seems to indicate destroy() // is called by the garbage collector and everything is good. // Something to keep in mind though. return 0; } /** * Write function that is called when session data is to be saved. * * @param string $sessId The current session ID * @param string $data The session data to write * * @return bool */ public function write($sessId, $data): bool { if ($this->writesDisabled) { return true; } return $this->saveSession($sessId, $data); } /** * A function that is called internally when session data is to be saved. * * @param string $sessId The current session ID * @param string $data The session data to write * * @return bool */ abstract protected function saveSession($sessId, $data): bool; }

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