Multiple field studies have suggested chemistry within a forest canopy is poorly understood due to inadequate detection and quantification of reactive biogenic emissions, such as terpenes. To measure emission rates of terpenes at Blodgett Forest, a coniferous forest in the Sierra Nevada mountains of California, we placed enclosures over branches of the dominant species at the site – Ponderosa p...

The use of polymer coated surface acoustic wave (SAW) sensor arrays is a very promising technique for highly sensitive and selective detection of volatile organic compounds (VOCs). We present new developments to achieve a low cost sensor setup with a sampling method enabling the highly reproducible detection of volatiles even in the ppb range. Since the VOCs of coffee are well known by gas chro...

the effects of rootstock on the volatile flavour components of page mandarin juice and peel were investigated in this study. juice flavour components were extracted by using poly dimethyl silaxane  membranes( pdms ) and eluted by pentane dichloromethane and then analyzed by gc-fid and gc-ms. peel flavour components were extracted by using cold-press and eluted by using n-hexane and then analyze...

background & aim: the genus tanacetum l. belongs to the family asteraceae and tribe anthemideae. according to the recent findings the number of tanacetum species in iran is 36, of which 12 are endemic. in this study the essential oil composition of tanacetum chiliophyllum var. oligocephalum was investigated for the first time.   experimental: the plant was collected during flowering stage f...

Residual solvents are organic volatile impurities that can occur in the manufacture of Active Pharmaceutical Ingredients (APIs). analysis pharmaceutical products is necessary not only because they represent a potential risk for human health due to their toxicity and undesirables side effects, but also may affect physicochemical proprieties product. The main objective this work was 29 residual s...

Abstract The standard method to evaluate human exposure volatile organic compounds (VOCs) is in general performed by sampling the air on sorbents followed liquid extraction and detection using laboratory gas chromatograph (GC). conventional time labor intensive employs a toxic solvent which adds risk factor as well waste. Hence, there have been increasing demands for portable GC instruments all...

ABSTRACT: Acrylamide is a chemical compound that has been widely used since the last century for various applications. It is also formed from carbohydrate and amino acid containing foods by application of heat particularly in fried potato products, coffee and bread. Since bread is one of the primary foods of Iranian people, the determination of acrylamide content in bread might be considered im...

Este trabalho descreve um método simples e rápido para a determinação de BTEX (benzeno, tolueno, etilbenzeno e xileno) em resíduos sólidos e soluções lixiviadas de resíduos sólidos aplicando a Norma Brasileira ABNT NBR 10004/2004. O método proposto possibilita a detecção direta de BTEX usando microextração em fase sólida e cromatografia a gás com detector por ionização em chama (HS-SPME GC/FID)...