نتایج جستجو برای: headspace sampling

تعداد نتایج: 214473  

Journal: :Journal of agricultural and food chemistry 2001
A Royer M Ménand A Grimault P Y Communal

The determination of dithiocarbamates in plant matrixes is generally carried out by spectrophotometric (European Norm EN 12396-1, 1996) or gas chromatography headspace (European Norm EN 12396-2, 1999) methods. However, the former method presents a risk of carbon disulfide loss during hydrolysis and distillation and its sensitivity is low, whereas the latter method is time-consuming. In comparis...

Journal: :The Onderstepoort journal of veterinary research 1991
H E Winterbach P J Apps

An automated headspace gas-chromatographic method has been developed for the determination of acetone in the milk, blood and urine of dairy cows. Five ml samples were saturated with 2 g of sodium chloride and equilibrated for 30 min at 90 degrees C in a Hewlett-Packard HP 19395 A automatic headspace sampler. The headspace volatiles were transferred without splitting to a 25 m x 0.3 mm x 0.4 mic...

Journal: :Analytical sciences : the international journal of the Japan Society for Analytical Chemistry 2009
Kanako Watanabe Koutaro Hasegawa Itaru Yamagishi Hideki Nozawa Masamitsu Takaba Osamu Suzuki

A very simple and sensitive method for the simultaneous analysis of naphthalene and p-dichlorobenzene in human whole blood and urine by headspace capillary gas chromatography-mass spectrometry (GC-MS) is presented. The advantages of the method were that as much as 1 mL of headspace vapor could be injected into a GC port in the splitless mode, and that the addition of deuterated naphthalene and ...

Journal: :The Annals of occupational hygiene 2009
Xingya Kuang Tumuluru Jaya Shankar Xiaotao T Bi C Jim Lim Shahab Sokhansanj Staffan Melin

Wood pellets emit CO, CO(2), CH(4), and other volatiles during storage. Increased concentration of these gases in a sealed storage causes depletion of concentration of oxygen. The storage environment becomes toxic to those who operate in and around these storages. The objective of this study was to investigate the effects of temperature, moisture, and the relative size of storage headspace on e...

The electrochemical coating technique was used for the preparation of a polypyrrole coating on a stainless-steel wire, and applied as a fibre for solid phase microextraction (SPME). The polypyrrole fibre was employed for analyzing four volatile aliphatic amines (ethylamine, propylamine, butylamine and pentylamine) in water by headspace SPME using gas chromatography-flame ionization detection (G...

2003

possibility of very selective separations that depend on the geometry of the molecules to be separated rather than the more generalized solubility mechanisms acting in gas}liquid chromatography. It should be theoretically possible to design adsorbents for particular separations. In the branch of liquid chromatography known as afRnity chromatography, for example, it is already possible to manufa...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید