نتایج جستجو برای: assisted headspace spme ua

تعداد نتایج: 139598  

Journal: :Zeitschrift fur Naturforschung. C, Journal of biosciences 2003
Deniz Tasdemir Betül Demirci Fatih Demirci Ali A Dönmez K Hüsnü Can Baser Peter Rüedi

Volatile constituents of various solvent extracts (n-hexane, CH2Cl2, H2O) of 15 different organs (leaves, flowers, fruits) of five Rhododendron species (Ericaceae) growing in Turkey were trapped with headspace solid-phase microextraction (HS-SPME) technique and analyzed by GC-MS. A total of 200 compounds were detected and identified from organic extracts, while the water extracts contained only...

Journal: :Journal of forensic sciences 2014
Karlie M McManaman Ruth Waddell Smith

Analysis of impurities in seized MDMA tablets can be used to determine the synthesis method used and to identify links among exhibits. However, no standardized method exists to generate impurity profiles, limiting comparisons among different laboratories. This research investigated the effect of extraction procedure and gas chromatography temperature program on the resulting impurity profiles. ...

Journal: :Journal of agricultural and food chemistry 2001
C Palma-Harris R F McFeeters H P Fleming

Investigations were carried out to determine whether flavor compounds characteristic for fresh cucumbers could be rapidly determined using a solid-phase microextraction (SPME) dynamic headspace sampling method combined with gas chromatography and flame ionization detection. Cucumbers were sampled, during blending, for fresh cucumber flavor compounds (E,Z)-2,6-nonadienal and (E)-2-nonenal. The G...

Journal: :Journal of chromatographic science 2010
J C Sullivan S M Budge A Timmins

A simple, rapid, and reliable method to detect residual levels of tert-butanol in liposomes using sec-butanol as an internal standard has been developed. Solid-phase microextraction (SPME) followed by gas chromatographic analysis was used to quantify the amount of residual tert-butanol in freeze-dried liposome material. Only 1 min was necessary for reproducible amounts of analyte to absorb onto...

Journal: :Journal of separation science 2005
Luigi Mondello Rosaria Costa Peter Quinto Tranchida Paola Dugo Maria Lo Presti Saverio Festa Alessia Fazio Giovanni Dugo

This investigation is based on the automated solid phase microextraction GC-MS analysis of the volatile fraction of a variety of coffee bean matrices. Volatile analytes were extracted by headspace (HS)-SPME which was achieved with the support of automated instrumentation. The research was directed towards various important aspects relating to coffee aroma analysis: monitoring of the volatile fr...

Journal: :Journal of environmental quality 2007
Lingshuang Cai Jacek A Koziel Yi Liang Anh Thu Nguyen Hongwei Xin

Poultry operations are associated with emissions of aerial ammonia (NH3), volatile organic compounds (VOCs), and odor, and the magnitude of emissions is influenced by manure management practices. As a manure treatment additive, zeolites have been shown to have the potential to control NH3. Because of their properties it is also expected that zeolites could effectively adsorb VOCs and odor. The ...

2014
Hanaa Yamani Nitin Mantri Paul D Morrison Edwin Pang

BACKGROUND The foraging choices of honey bees are influenced by many factors, such as floral aroma. The composition of volatile compounds influences the bioactivity of the aromatic plants and honey produced from them. In this study, Agastache rugosa was evaluated as part of a project to select the most promising medicinal plant species for production of bioactive honey. METHODS Headspace soli...

Journal: :Journal of chromatographic science 2002
Akira Namera Mikio Yashiki Tohru Kojima Makoto Ueki

An automated extraction and determination method for the gas chromatography (GC)-mass spectrometry (MS) analysis of amphetamine-related drugs in human urine is developed using headspace solid-phase microextraction (SPME) and in-matrix derivatization. A urine sample (0.5 mL, potassium carbonate (5 M, 1.0 mL), sodium chloride (0.5 g), and ethylchloroformate (20 microL) are put in a sample vial. A...

Journal: :Chemosphere 2017
Heidi Birch Henrik R Andersen Mike Comber Philipp Mayer

During simulation-type biodegradation tests, volatile chemicals will continuously partition between water phase and headspace. This study addressed how (1) this partitioning affects test results and (2) can be accounted for by combining equilibrium partition and dynamic biodegradation models. An aqueous mixture of 9 (semi)volatile chemicals was first generated using passive dosing and then dilu...

Journal: :Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment 2010
N Rastkari R Ahmadkhaniha M Yunesian L J Baleh A Mesdaghinia

A reliable and sensitive method for simultaneous determination of bisphenol A (BPA) and bisphenol F (BPF) in canned food by gas chromatography-mass spectrometry (GC/MS) is described after extraction and pre-concentration by a new solid-phase microextraction (SPME) adsorbent. The potential of single-walled carbon nanotubes (SWCNTs) as SPME adsorbent for the pre-concentration of environmental con...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید