Search results for " organic compounds"
showing 10 items of 171 documents
Volatile Profiles of Emissions from Different Activities Analyzed Using Canister Samplers and Gas Chromatography-Mass Spectrometry (GC/MS) Analysis: …
2017
The objective of present study was to identify volatile organic compounds (VOCs) emitted from several sources (fuels, traffic, landfills, coffee roasting, a street-food laboratory, building work, indoor use of incense and candles, a dental laboratory, etc.) located in Palermo (Italy) by using canister autosamplers and gas chromatography-mass spectrometry (GC-MS) technique. In this study, 181 VOCs were monitored. In the atmosphere of Palermo city, propane, butane, isopentane, methyl pentane, hexane, benzene, toluene, meta- and para-xylene, 1,2,4 trimethyl benzene, 1,3,5 trimethyl benzene, ethylbenzene, 4 ethyl toluene and heptane were identified and quantified in all sampling sites.
The responses of shoot-root-rhizosphere continuum to simultaneous fertilizer addition, warming, ozone and herbivory in young Scots pine seedlings in …
2017
Abstract It is not clear how climate change in combination with increasing soil nitrogen availability and herbivory affects boreal forests, the largest terrestrial biome in the world. In this study, Scots pine ( Pinus sylvestris ) seedlings were exposed to moderate warming (ca. 1 °C), 1.5 × ambient ozone (O 3 ) concentration, fertilizer addition (120 kg N ha −1 yr −1 ) and shoot herbivory by pine sawfly ( Acantholyda posticalis ) alone and in combination. We measured fine root morphology, mycorrhizal colonization level, root fungal biomass (ergosterol), rhizosphere emission of biogenic volatile organic compounds (BVOCs), and microbial biomass (PLFAs) in the rhizosphere soil as well as seedl…
Floral scent in a sexually deceptive Ophrys orchid: from headspace collections to solvent extractions
2018
Sexually deceptive orchid flowers use visual, tactile and olfactory cues of female insects in order to attract males of one or a few closely related species as pollinators. Ophrys L. is the most species-rich genus of sexually deceptive orchids in the Mediterranean Basin. Despite Ophrys pollinated by Andrena male bees use alkanes and mainly alkenes with specific double-bond positions as key signals that trigger pseudocopulatory behavior, some volatile organic compounds (VOCs) with low molecular weight were found as long-range attractants non-eliciting copulatory behavior. Since floral scents in Ophrys have been extensively studied by solvent extractions here we aimed to understand which flor…
An integrated proteomic and metabolomic study to evaluate the effect of nucleus-cytoplasm interaction in a diploid citrus cybrid between sweet orange…
2018
Key message: Our results provide a comprehensive overview how the alloplasmic condition might lead to a significant improvement in citrus plant breeding, developing varieties more adaptable to a wide range of conditions. Abstract: Citrus cybrids resulting from somatic hybridization hold great potential in plant improvement. They represent effective products resulting from the transfer of organelle-encoded traits into cultivated varieties. In these cases, the plant coordinated array of physiological, biochemical, and molecular functions remains the result of integration among different signals, which derive from the compartmentalized genomes of nucleus, plastids and mitochondria. To dissect …
Spoilage potential of Brettanomyces bruxellensis strains isolated from Italian wines
2018
Abstract Brettanomyces bruxellensis is an important wine spoilage agent. In this study a population of Brettanomyces strains isolated from Italian wines was thoroughly investigated to evaluate adaptability to wine conditions and spoilage potential. The presumptive isolates of Brettanomyces were identified at species level with 26S rRNA gene sequencing and species-specific PCR, and subsequently subjected to analysis of intra-species variability through the study of intron splice sites (ISS-PCR). Although, some strains were tracked in wines from different regions, extensive genetic biodiversity was observed within the B. bruxellensis population investigated. All strains were evaluated for the…
Study of Mass Oxygen Transfer in a Biotrickling Filter for Air Pollution Control
2012
Biotrickling filtration is a potential and cost effective alternative for the treatment of volatile organic compound (VOC) emissions in air, so it is necessary to deepen into the key aspects of design and operation for the optimization of this technology. One of these factors is the oxygen mass transfer of the process. This study would facilitate the selection of the packing material and the mathematical modelling and simulation of bioreactors. Four plastic packing materials with a different specific surface area have been evaluated in terms of oxygen mass transfer. For the tested range of superficial liquid velocities, data show a relationship between the kLa and the superficial liquid vel…
Biotrickling filter modeling for styrene abatement. Part 1: Model development, calibration and validation on an industrial scale
2017
Abstract A three-phase dynamic mathematical model based on mass balances describing the main processes in biotrickling filtration: convection, mass transfer, diffusion, and biodegradation was calibrated and validated for the simulation of an industrial styrene-degrading biotrickling filter. The model considered the key features of the industrial operation of biotrickling filters: variable conditions of loading and intermittent irrigation. These features were included in the model switching from the mathematical description of periods with and without irrigation. Model equations were based on the mass balances describing the main processes in biotrickling filtration: convection, mass transfe…
Removal of acetone from air emissions by biotrickling filters: providing solutions from laboratory to full-scale
2018
A full-scale biotrickling filter (BTF) treating acetone air emissions of wood-coating activities showed difficulties to achieve outlet concentrations lower than 125 mg C m-3, especially for high inlet concentrations and oscillating emissions. To solve this problem, a laboratory investigation on acetone removal was carried out simulating typical industrial conditions: discontinuous and variable inlet concentrations and intermittent spraying. The results were evaluated in terms of removal efficiency and outlet gas emission pattern. Industrial emissions and operational protocols were simulated: inlet load up to 70 g C m-3 h-1 during 2 cycles of 4 h per day and intermittent trickling of 15 min …
Advanced methods of plant disease detection. A review
2014
International audience; Plant diseases are responsible for major economic losses in the agricultural industry worldwide. Monitoring plant health and detecting pathogen early are essential to reduce disease spread and facilitate effective management practices. DNA-based and serological methods now provide essential tools for accurate plant disease diagnosis, in addition to the traditional visual scouting for symptoms. Although DNA-based and serological methods have revolutionized plant disease detection, they are not very reliable at asymptomatic stage, especially in case of pathogen with systemic diffusion. They need at least 1–2 days for sample harvest, processing, and analysis. Here, we d…
Understanding insect foraging in complex habitats by comparing trophic levels: insights from specialist host-parasitoid-hyperparasitoid systems
2019
Insects typically forage in complex habitats in which their resources are surrounded by non-resources. For herbivores, pollinators, parasitoids, and higher level predators research has focused on how specific trophic levels filter and integrate information from cues in their habitat to locate resources. However, these insights frequently build specific theory per trophic level and seldom across trophic levels. Here, we synthesize advances in understanding of insect foraging behavior in complex habitats by comparing trophic levels in specialist host-parasitoid-hyperparasitoid systems. We argue that resources may become less apparent to foraging insects when they are member of higher trophic …