The origin of agricultural products is gaining in appreciation while often hard to determine for various reasons. Geographical origin may be resolved using a combination of chemical and physical analytical technologies. In the present case of Lily of the Valley (Convallaria majalis) rhizomes, we investigated an exploratory set of material from The Netherlands, three other European (EU) countrie...

Orange trees are widely cultivated in regions with high concentrations of tropospheric ozone. Citrus absorb ozone through their stomata and emit volatile organic compounds (VOC), which, together with soil emissions of NO, contribute to non-stomatal ozone removal. In a Valencia orange orchard in Exeter, California, we used fast sensors and eddy covariance to characterize water and ozone fluxes. ...

The different steps of the foraging process of wireworms (Coleoptera: Elateridae) would be better understood if accurate and holistic information regarding the role of plant-produced chemicals constituting their environment were available. Volatile organic compounds (VOC) play important roles in the interactions between plants and insects in many ecosystems, whether they take place aboveground ...

California dairies house approximately 1.8 million lactating and 1.5 million dry cows and heifers. State air regulatory agencies view these dairies as a major air pollutant source, but emissions data are sparse, particularly for volatile organic compounds (VOCs). The objective of this work was to determine VOC emissions from lactating and dry dairy cows and their waste using an environmental ch...

A study was conducted to evaluate the. use of volatile organic microbial metabolites, particularly geosmin and 2-methylisoborneol, as indicators of activity of specific groups of microorganisms (actinomycetes, bacteria, or fungi) in soil. Substrates and selective antibiotics were added to soil microcosms to establish different soil microbial communities; volatile organic compounds (VOCs) in the...

Abstract. Vehicular emissions are an important source for volatile organic compounds (VOCs) in urban and downwind regions. In this study, we conducted a chassis dynamometer study to investigate VOC from vehicles using gasoline, diesel, liquefied petroleum gas (LPG) as fuel. Time-resolved chemically characterized by proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) with high...

In this paper, we propose a volatile organic compound (VOC) gas sensing system with high sensitivity and a wide dynamic range that is based on the principle of the heterodyne frequency modulation method. According to this method, the time period of the sensing signal shift when Nile Red containing a VOC-sensitive membrane of a fiber-optic sensing element comes into contact with a VOC. This sens...

Control of paratuberculosis in livestock is hampered by the low sensitivity of established direct and indirect diagnostic methods. Like other bacteria, Mycobacterium avium subsp. paratuberculosis (MAP) emits volatile organic compounds (VOCs). Differences of VOC patterns in breath and feces of infected and not infected animals were described in first pilot experiments but detailed information on...

Captan belongs to an important group of sulfcnimidc fungicides, commonly used on major crops, fruits and ornamentals. In this study, a laboratory scale apparatus has been constructed to investigate the thermal decomposition of captan in gas phase reactions, similar to those that occur in fires, burning of wood and other biomass treated or contaminated with pesticides. The apparatus comprises a ...

This study examines inter-brand, intra-brand and intra-model variations in volatile organic chemical (VOC) levels inside new cars. The effect of temperature on interior VOC levels was examined using model automobiles with and without the air-conditioning running. Potential sources of VOC were assessed by comparing VOC levels with two interior trims (leather and fabric) and by analyzing VOC emis...