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Fons, Françoise, Didier Froissard, Jean-Marie Bessière, Bruno Buatois, and Sylvie Rapior. "Biodiversity of Volatile Organic Compounds from Five French Ferns." Natural Product Communications 5, no. 10 (2010): 1934578X1000501. http://dx.doi.org/10.1177/1934578x1000501028.
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Five French ferns belonging to different families were investigated for volatile organic compounds (VOC) by GC-MS using organic solvent extraction. Fifty-five VOC biosynthesized from the shikimic, lipidic and terpenic pathways including monoterpenes, sesquiterpenes and carotenoid-type compounds were identified. The main volatile compound of Adiantum Capillus-Veneris L. (Pteridaceae) was ( E)-2-decenal with a plastic or “stink bug” odor. The volatile profiles of Athyrium filix-femina (L.) Roth (Woodsiaceae) and Blechnum spicant (L.) Roth (Blechnaceae) showed similarities, with small amounts of isoprenoids and the same main volatile compounds, i.e., 2-phenylethanal (odor of lilac and hyacinth) and 1-octen-3-ol (mushroom-like odor). The main volatile compound of Dryopteris filix-mas (L.) Schott (Dryopteridaceae) was ( E)-nerolidol with a woody or fresh bark note. Polyketides, as acylfilicinic acids, were mainly identified in this fern. Oreopteris limbosperma (Bellardi ex. All.) J. Holub (Thelypteridaceae), well-known for its lemon smell, contained the highest biodiversity of VOC. Eighty percent of the volatiles was issued from the terpenic pathway. The main volatiles were ( E)-nerolidol, α-terpineol, β-caryophyllene and other minor monoterpenes (for example, linalool, pinenes, limonene, and γ-terpinen-7-al). It was also the fern with the highest number of carotenoid-type derivatives, which were identified in large amounts. Our results were of great interest underlying new industrial valorisation for ferns based on their broad spectrum of volatiles.
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Apriyanto, Donni Kis, and Mitrayana Mitrayana. "SERAPAN SENYAWA ORGANIK VOLATIL SEBAGAI BIOMARKER PENYAKIT KANKER PARU: SUATU MINI REVIEW." Biomedika 12, no. 2 (2020): 58–64. http://dx.doi.org/10.23917/biomedika.v12i2.10114.
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ABSTRAKUlasan ini merupakan hasil studi literatur yang memberikan tinjauan umum serapan senyawa-senyawa organik volatil yang dianggap sebagai biomarker kanker paru. Senyawa-senyawa ini dapat menyerap pada panjang gelombang tertentu. Senyawa-senyawa organik volatil yang teridentifikasi didaftar dan dijabarkan panjang gelombang yang dapat mereka serap. Studi literatur ini menyajikan kelompok senyawa-senyawa organik volatil dapat menyerap pada rentang panjang gelombang inframerah. Hasil ulasan ini mungkin dapat bermanfaat untuk pengembangan skrinning kanker paru dengan menggunakan alat spektroskopi fotoakustik yang menggunakan sumber laser pada rentang panjang gelombang inframerah atau ultraviolet dengan memanfaatkan serapan panjang gelombang oleh senyawa-senyawa tertentu.Keyword: Biomarker Kanker Paru,Senyawa Organik Volatil, Spektroskopi ABSTRACTThis review is the result of a literature study that provides a general collection of volatile organic compounds (VOC) which are considered as markers for lung cancer. These compounds can absorb certain long waves. The volatile organic compounds identified are listed and described in wavelengths that they can absorb. Literature studies that produce volatile organic compounds in the analysis wavelength range. The results of this review may be useful for the development of lung cancer screening by photoacoustic spectroscopic devices that use laser sources in the range of infrared or ultraviolet wavelengths by utilizing wavelength absorb by certain compounds.Keyword: Lung Cancer Biomarker, Volatile Organic Compounds, Spectroscopy
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Jergl, Zdeněk. "Long-term VOC emissions emitted by furniture parts." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 55, no. 1 (2007): 65–70. http://dx.doi.org/10.11118/actaun200755010065.
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The contribution refers to the problems of long-lasting emissions of VOC (volatile organic compounds) emitted from surface finishing furniture components. Furniture is one of the sources of VOC (volatile organic compounds) in living and working environment. By long-lasting affecting on a human body, higher emission concentrations of VOC in interior can cause health problems.Time is a significant factor influencing the number of VOC (volatile organic compounds) emitted from surface finishing furniture components. The number of long-term emissions was examined in particular phases of production of furniture components.The comparison was focused on a difference in surface finishing of furniture components with water-diluted materials and solvent lacquer materials.The compound of water-diluted materials and solvent lacquer materials has an effect of a quantity of emitted VOC.The quantitative and qualitative determination of VOC emissions from lacquer materials is the result of the carried out analyses.
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Kornilova, Anna, Lin Huang, Marina Saccon, and Jochen Rudolph. "Stable carbon isotope ratios of ambient aromatic volatile organic compounds." Atmospheric Chemistry and Physics 16, no. 18 (2016): 11755–72. http://dx.doi.org/10.5194/acp-16-11755-2016.
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Abstract. Measurements of mixing ratios and stable carbon isotope ratios of aromatic volatile organic compounds (VOC) in the atmosphere were made in Toronto (Canada) in 2009 and 2010. Consistent with the kinetic isotope effect for reactions of aromatic VOC with the OH radical the observed stable carbon isotope ratios are on average significantly heavier than the isotope ratios of their emissions. The change of carbon isotope ratio between emission and observation is used to determine the extent of photochemical processing (photochemical age, ∫ [OH]dt) of the different VOC. It is found that ∫ [OH]dt of different VOC depends strongly on the VOC reactivity. This demonstrates that for this set of observations the assumption of a uniform ∫ [OH]dt for VOC with different reactivity is not justified and that the observed values for ∫ [OH]dt are the result of mixing of VOC from air masses with different values for ∫ [OH]dt. Based on comparison between carbon isotope ratios and VOC concentration ratios it is also found that the varying influence of sources with different VOC emission ratios has a larger impact on VOC concentration ratios than photochemical processing. It is concluded that for this data set the use of VOC concentration ratios to determine ∫ [OH]dt would result in values for ∫ [OH]dt inconsistent with carbon isotope ratios and that the concept of a uniform ∫ [OH]dt for an air mass has to be replaced by the concept of individual values of an average ∫ [OH]dt for VOC with different reactivity.
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Berger, Shastine K., Rosario C. Morales, Katherine A. McCown, Kylie C. Wilson, Bertram T. Jobson, and Nancy A. C. Johnston. "Analysis of Volatile Organic Compounds from Compost." Atmosphere 16, no. 5 (2025): 591. https://doi.org/10.3390/atmos16050591.
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Many US states have adopted regulations to divert food waste from landfills to composts. While this may lower greenhouse emissions from landfills, volatile organic compound (VOC) emissions from compost may contain hazardous air pollutants or produce odors, posing potential public health concerns. Effective methods to analyze speciated VOCs in compost are needed to better understand VOC source generation. Here, a two-component compost sampling method was developed and employed consisting of a chilled impinger and pump apparatus to trap water-soluble VOCs, and dual sorbent tubes to capture hydrophobic VOCs in yard and food/yard waste compost. VOCs were measured via headspace gas chromatography with flame ionization detection (HS-GC-FID) and thermal desorption–gas chromatography–mass spectrometry (TD-GC-MS). Overall, there was higher VOC generation within higher-temperature compost piles, with concentrations ranging up to 27,000 ppm for ethanol and 3500 ppm for methanol. Alpha-pinene and D-limonene were seen in these piles with concentrations over 1600 ppb. Methanol and ethanol were more than one thousand times as concentrated in mixed food/yard waste than yard waste alone, while terpenes were seen in slightly higher concentrations for yard waste than the mixed food/yard waste. Methanol was observed to be higher than permissible indoor levels and may pose potential health risks.
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Kratt, Lothar, and Johannes Münz. "UV-Licht gegen VOC." UmweltMagazin 51, no. 05-06 (2021): 12–14. http://dx.doi.org/10.37544/0173-363x-2021-05-06-12.
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Yu, Man, Shao Peng Wu, Mei Zhu Chen, and Hong Hua Zhang. "Evaluation of Volatile Organic Compounds from Asphalt Using UV-Visible Spectrometer." Advanced Materials Research 472-475 (February 2012): 432–36. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.432.
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In order to evaluate volatile organic compounds (VOC) from asphalt, this paper explored to use ultraviolet and visible spectroscopy (UV-VIS) as the detection method of VOC. 288nm wavelength was selected as the characteristic absorption wavelength of VOC, finding that VOC quality and its absorbance value showed a good linear relationship which could be the basis for evaluation in this research. Experiments were carried out under different conditions, results of which showed that VOC emission was related to temperatures and asphalt specimens. Moreover, VOC emission increased with increasing temperatures. Results under non-high temperatures conditions showed that VOC emission during its service process should not be ignored.
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Liu, Yu, Jun Shen, and Xiao Dong Zhu. "Volatile Organic Compounds Emissions of Particleboards in Response to Processing Parameters." Advanced Materials Research 250-253 (May 2011): 943–46. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.943.
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The purpose of this study is to reveal the concentration variations of VOC concentrations of larch particleboards with different processing parameters. The mat moisture content (MC), panel type and density were chosen as the influencing factors to investigate the VOC emissions after processing, and consequently provide basic guideline for the selection of processing parameters of particleboards to control the pollutants. 1m3 environmental chamber and portable VOC monitor were used for VOC sampling and analysis. The results showed that these factors had significant impact on VOC concentrations. The increase of MC, board panel and density had a positive effect on VOC emissions. With the MC and board density various in the ranges from 6%-14% and 0.60-0.80 g·cm-3, the TVOC concentrations increased 42.6% and 74.7% separately. The three layers particleboard had the higher concentration than the single layer particleboard.
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Kilgour, Delaney B., Gordon A. Novak, Megan S. Claflin, Brian M. Lerner, and Timothy H. Bertram. "Production of oxygenated volatile organic compounds from the ozonolysis of coastal seawater." Atmospheric Chemistry and Physics 24, no. 6 (2024): 3729–42. http://dx.doi.org/10.5194/acp-24-3729-2024.
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Abstract. Dry deposition of ozone (O3) to the ocean surface and the ozonolysis of organics in the sea surface microlayer (SSML) are potential sources of volatile organic compounds (VOCs) to the marine atmosphere. We use a gas chromatography system coupled to a Vocus proton-transfer-reaction time-of-flight mass spectrometer to determine the chemical composition and product yield of select VOCs formed from ozonolysis of coastal seawater collected from Scripps Pier in La Jolla, California. Laboratory-derived results are interpreted in the context of direct VOC vertical flux measurements made at Scripps Pier. The dominant products of laboratory ozonolysis experiments and the largest non-sulfur emission fluxes measured in the field correspond to Vocus CxHy+ and CxHyOz+ ions. Gas chromatography (GC) analysis suggests that C5–C11 oxygenated VOCs, primarily aldehydes, are the largest contributors to these ion signals. In the laboratory, using a flow reactor experiment, we determine a VOC yield of 0.43–0.62. In the field at Scripps Pier, we determine a maximum VOC yield of 0.04–0.06. Scaling the field and lab VOC yields for an average O3 deposition flux and an average VOC structure results in an emission source of 10.7 to 167 Tg C yr−1, competitive with the DMS source of approximately 20.3 Tg C yr−1. This study reveals that O3 reactivity to dissolved organic carbon can be a significant carbon source to the marine atmosphere and warrants further investigation into the speciated VOC composition from different seawater samples and the reactivities and secondary organic aerosol (SOA) yields of these molecules in marine-relevant, low NOx conditions.
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Nekrasova, Larisa P. "Detection of volatile organic compounds in soils (literature review)." Hygiene and sanitation 103, no. 10 (2024): 1149–54. http://dx.doi.org/10.47470/0016-9900-2024-103-10-1149-1154.
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Volatile organic compounds (VOC) are major environmental pollutants. Due to their high mobility, they penetrate into all environmental objects, pose an environmental threat and health risks. Getting into the soil, they deteriorate its quality. VOC content requires reliable control. There is presented a review of the literature, including methods of the US Environmental Protection Agency, and regulatory and methodological documents of the Russian Federation regulating methods of selection, storage, preparation and analysis of soil samples for VOC content. The dominant place among methods for monitoring for VOCs belongs to gas chromatography with various types of detectors. For multicomponent analysis of complex objects, gas chromatography with mass selective detection is used due to the wide capabilities provided by the mass detector. A universal mass spectrometry method used in analytical laboratories is electron impact ionization mass spectrometry. For research purposes, modern highly sensitive methods are used – mass spectrometry based on the proton transfer reaction PTR-MS, ion trap mass spectrometry PIT-MS, negative ion ionization mass spectrometry NI-PT-CIMS, time-of-flight mass spectrometry of the transfer reaction proton PTR-TOF-MS. The collection and storage of samples for VOC analysis requires compliance with regulations to prevent both loss of analytes and sample contamination. Sample preparation includes methods such as vacuum and azeotropic distillation, thermal desorption, liquid extraction, various options for static and dynamic headspace analysis.
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Acton, W. Joe F., Zhonghui Huang, Brian Davison, et al. "Surface–atmosphere fluxes of volatile organic compounds in Beijing." Atmospheric Chemistry and Physics 20, no. 23 (2020): 15101–25. http://dx.doi.org/10.5194/acp-20-15101-2020.
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Abstract. Mixing ratios of volatile organic compounds (VOCs) were recorded in two field campaigns in central Beijing as part of the Air Pollution and Human Health in a Chinese Megacity (APHH) project. These data were used to calculate, for the first time in Beijing, the surface–atmosphere fluxes of VOCs using eddy covariance, giving a top-down estimation of VOC emissions from a central area of the city. The results were then used to evaluate the accuracy of the Multi-resolution Emission Inventory for China (MEIC). The APHH winter and summer campaigns took place in November and December 2016 and May and June 2017, respectively. The largest VOC fluxes observed were of small oxygenated compounds such as methanol, ethanol + formic acid and acetaldehyde, with average emission rates of 8.31 ± 8.5, 3.97 ± 3.9 and 1.83 ± 2.0 nmol m−2 s−1, respectively, in the summer. A large flux of isoprene was observed in the summer, with an average emission rate of 5.31 ± 7.7 nmol m−2 s−1. While oxygenated VOCs made up 60 % of the molar VOC flux measured, when fluxes were scaled by ozone formation potential and peroxyacyl nitrate (PAN) formation potential the high reactivity of isoprene and monoterpenes meant that these species represented 30 % and 28 % of the flux contribution to ozone and PAN formation potential, respectively. Comparison of measured fluxes with the emission inventory showed that the inventory failed to capture the magnitude of VOC emissions at the local scale.
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Tirillini, Bruno, and Filippo Maggi. "Volatile Organic Compounds of the Glandular Trichomes of Ocimum basilicum and Artifacts during the Distillation of the Leaves." Applied Sciences 11, no. 16 (2021): 7312. http://dx.doi.org/10.3390/app11167312.
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Focusing on volatile organic compounds (VOC) of Ocimum basilicum, this study aims to determine the chemical composition of VOC in secretory trichomes and compare it with that of essential oil obtained by hydrodistillation of leaves. The technique of extracting the content of glandular trichomes refers to the microneedle shuttle analysis. Hydrodistillation of fresh leaves was done with a Clevenger distiller (EO). The chemical compositions were determined by GC/FID and GC/MS. The head of the capitate trichomes does not contain volatile compounds. Fifty volatile compounds were detected in the EO, and twenty-four volatile compounds were detected in the VOC; the main components were eugenol (from 15.47 ± 1.05% to 41.89 ± 2.83%) and linalool (from 32.05 ± 2.57% to 28.99 ± 2.32%), respectively. During the distillation of the basil leaves 26 artifacts are formed. The composition of the essential oil of O. basilicum therefore depends not only on the plant but also on the method used to obtain it.
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Suschka, Jan, Bozena Mrowiec, and Grazyna Kuszmider. "Volatile organic compounds (VOC) at some sewage treatment plants in Poland." Water Science and Technology 33, no. 12 (1996): 273–76. http://dx.doi.org/10.2166/wst.1996.0348.
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Volatile organic compounds have been measured at two relatively large sewage treatment plants. Quantitative estimation of benzene, toluene, m.p-xylene, o-xylene and isopropylbenzene have been made for raw sewage, sewage after primary treatment and after biological treatment. Also measurements of 14 different volatile organic compounds in the ambient air, close to screens, and the air above (0.5 m above) aeration tanks have been done. Tests on air stripping of added volatile organic compounds to clean water have been performed in parallel in the laboratory. The removal of examined VOCs in full scale treatment plants was very much below the expected level. In the low loaded activated sludge process the removal was between 2 and 56%, depending on the compound considered. The behavior of volatile organic compounds in laboratory tests was very much different. The concentration of VOCs in the air of rooms where bar racks have been installed was found to be very high. The concentration of toluene in the ambient air could be as high as 460 μg/m3.
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Haiek, Maisa, Vladislav Dvoyris, Yoav Y. Broza, Hossam Haick, Ervin Weiss, and Yael Houri-Haddad. "Bacterial Volatile Organic Compounds as Potential Caries and Periodontitis Disease Biomarkers." International Journal of Molecular Sciences 26, no. 8 (2025): 3591. https://doi.org/10.3390/ijms26083591.
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Oral diseases represent a significant global health and economic burden, necessitating the development of effective diagnostic tools. This study investigates the volatile organic compound (VOC) profiles of bacteria associated with dental caries and periodontal disease to explore their potential as diagnostic biomarkers. Four microbial strains—Streptococcus mutans (700610), Streptococcus sanguis (NCO 2863), Porphyromonas gingivalis (ATCC 33277), and Fusobacterium nucleatum (PK1594)—were cultured (N = 24), alongside intraoral samples (N = 60), from individuals with common oral diseases. Headspace VOCs were analyzed using gas chromatography-mass spectrometry (GC-MS), and statistical analyses were conducted by applying non-parametric Wilcoxon and Kruskal–Wallis tests. VOC identification was performed using the NIST14 database. Strain-specific VOC signatures were identified, with P. gingivalis and F. nucleatum exhibiting distinct profiles from each other and from Streptococcus strains. Comparative analysis of disease cohorts revealed statistically significant differences at multiple retention times between caries, gingivitis, and periodontitis. These findings suggest that VOC profiling enables differentiation between bacterial strains and disease phenotypes, supporting their potential application as diagnostic biomarkers for oral diseases. This study establishes a foundational framework for VOC-based diagnostic methodologies in dental pathology.
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Hu, Yuanyuan, Ge Liu, Chaomin Sun, and Shimei Wu. "Volatile Organic Compounds Produced by a Deep-Sea Bacterium Efficiently Inhibit the Growth of Pseudomonas aeruginosa PAO1." Marine Drugs 22, no. 5 (2024): 233. http://dx.doi.org/10.3390/md22050233.
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The deep-sea bacterium Spongiibacter nanhainus CSC3.9 has significant inhibitory effects on agricultural pathogenic fungi and human pathogenic bacteria, especially Pseudomonas aeruginosa, the notorious multidrug-resistant pathogen affecting human public health. We demonstrate that the corresponding antibacterial agents against P. aeruginosa PAO1 are volatile organic compounds (VOCs, namely VOC-3.9). Our findings show that VOC-3.9 leads to the abnormal cell division of P. aeruginosa PAO1 by disordering the expression of several essential division proteins associated with septal peptidoglycan synthesis. VOC-3.9 hinders the biofilm formation process and promotes the biofilm dispersion process of P. aeruginosa PAO1 by affecting its quorum sensing systems. VOC-3.9 also weakens the iron uptake capability of P. aeruginosa PAO1, leading to reduced enzymatic activity associated with key metabolic processes, such as reactive oxygen species (ROS) scavenging. Overall, our study paves the way to developing antimicrobial compounds against drug-resistant bacteria by using volatile organic compounds.
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Mohd Tombel, Nor Syahira, Hasan Firdaus Mohd Zaki, and Hanna Farihin Mohd Fadglullah. "FEATURE EXTRACTION AND SUPERVISED LEARNING FOR VOLATILE ORGANIC COMPOUNDS GAS RECOGNITION." IIUM Engineering Journal 24, no. 2 (2023): 407–20. http://dx.doi.org/10.31436/iiumej.v24i2.2832.
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The emergence of advanced technologies, particularly in the field of artificial intelligence (AI), has sparked significant interest in exploring their potential benefits for various industries, including healthcare. In the medical sector, the utilization of sensing systems has proven valuable for diagnosing pulmonary diseases by detecting volatile organic compounds (VOCs) in exhaled breath. However, the identification of the most informative and discriminating features from VOC sensor arrays remains an unresolved challenge, essential for achieving robust VOC class recognition. This research project aims to investigate effective feature extraction techniques that can be employed as discriminative features for machine learning algorithms. A preliminary dataset was used to predict VOC classification through the application of five supervised machine learning algorithms: k-Nearest Neighbors (kNN), Random Forest (RF), Support Vector Machines (SVM), Logistic Regression (LR), and Artificial Neural Networks (ANN). Ten feature extraction methods were proposed based on changes in sensor response as inputs to classify three types of gases in the dataset. The performance of each model was evaluated and compared using k-Fold cross-validation (k=10) and metrics derived from the confusion matrix. The results demonstrate that the RF model achieved the highest mean accuracy and standard deviation, with values of 0.813 ± 0.035, followed closely by kNN with 0.803 ± 0.033. Conversely, LR, SVM (kernel=Polynomial), and ANN exhibited poor performances when applied to the VOC dataset, with accuracies of 0.447 ± 0.035, 0.403 ± 0.041, and 0.419 ± 0.035, respectively. Therefore, this paper provides evidence that classifying VOC gases based on sensor responses is feasible and emphasizes the need for further research to explore sensor array analysis to enhance feature extraction techniques. ABSTRAK: Perkembangan teknologi canggih, khususnya dalam bidang kecerdasan buatan (AI), telah mencetuskan minat yang ketara dalam menerokai manfaatnya untuk pelbagai industri, termasuk bidang kesihatan. Dalam sektor perubatan, penggunaan sistem penderiaan telah terbukti bernilai untuk mendiagnosis penyakit paru-paru dengan mengesan sebatian organik meruap (VOC) dalam nafas yang dihembus manusia. Walau bagaimanapun, pengenalpastian ciri yang paling bermaklumat dan mendiskriminasi daripada penderia VOC kekal sebagai cabaran yang tidak dapat diselesaikan, penting untuk mencapai pengiktirafan kelas VOC yang kukuh. Projek penyelidikan ini bertujuan untuk menyiasat teknik pengekstrakan ciri yang berkesan yang boleh digunakan sebagai ciri diskriminatif untuk algoritma pembelajaran mesin. Set data awal digunakan untuk meramalkan klasifikasi VOC melalui aplikasi lima algoritma pembelajaran mesin yang diselia: k-Nearest Neighbors (kNN), Random Forest (RF), Support Vector Machines (SVM), Logistic Regression (LR), dan Artificial Neural Networks (ANN). Sepuluh kaedah pengekstrakan ciri telah dicadangkan berdasarkan perubahan dalam tindak balas penderia sebagai input untuk mengklasifikasikan tiga jenis gas dalam set data. Prestasi setiap model telah dinilai dan dibandingkan menggunakan pengesahan silang k-Fold (k=10) dan metrik yang diperoleh daripada confusion matriks . Keputusan menunjukkan bahawa model RF mencapai ketepatan minima tertinggi dan sisihan piawai, dengan nilai 0.813 ± 0.035, diikuti oleh kNN dengan 0.803 ± 0.033. Sebaliknya, LR, SVM (kernel=Polinomial), dan ANN mempamerkan prestasi yang lemah apabila digunakan pada dataset VOC, dengan ketepatan masing-masing 0.447 ± 0.035, 0.403 ± 0.041 dan 0.419 ± 0.035. Oleh itu, kertas kerja ini memberikan bukti bahawa mengklasifikasikan gas VOC berdasarkan tindak balas penderia adalah boleh dilaksanakan dan menekankan keperluan untuk penyelidikan lanjut untuk meneroka analisis tatasusunan penderia untuk meningkatkan teknik pengekstrakan ciri.
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Salman, Dahlia, Wadah Ibrahim, Amisha Kanabar, et al. "The variability of volatile organic compounds in the indoor air of clinical environments." Journal of Breath Research 16, no. 1 (2021): 016005. http://dx.doi.org/10.1088/1752-7163/ac3565.
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Abstract The development of clinical breath-analysis is confounded by the variability of background volatile organic compounds (VOCs). Reliable interpretation of clinical breath-analysis at individual, and cohort levels requires characterisation of clinical-VOC levels and exposures. Active-sampling with thermal-desorption/gas chromatography-mass spectrometry recorded and evaluated VOC concentrations in 245 samples of indoor air from three sites in a large National Health Service (NHS) provider trust in the UK over 27 months. Data deconvolution, alignment and clustering isolated 7344 features attributable to VOC and described the variability (composition and concentration) of respirable clinical VOC. 328 VOC were observed in more than 5% of the samples and 68 VOC appeared in more than 30% of samples. Common VOC were associated with exogenous and endogenous sources and 17 VOC were identified as seasonal differentiators. The presence of metabolites from the anaesthetic sevoflurane, and putative-disease biomarkers in room air, indicated that exhaled VOC were a source of background-pollution in clinical breath-testing activity. With the exception of solvents, and waxes associated with personal protective equipment (PPE), exhaled VOC concentrations above 3 µg m−3 are unlikely to arise from room air contamination, and in the absence of extensive survey-data, this level could be applied as a threshold for inclusion in studies, removing a potential environmental confounding-factor in developing breath-based diagnostics.
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Ciccioli, P., A. Cecinato, E. Brancaleoni, M. Frattoni, F. Bruner, and M. Maione. "Occurrence of Oxygenated Volatile Organic Compounds (VOC) in Antarctica." International Journal of Environmental Analytical Chemistry 62, no. 3 (1996): 245–53. http://dx.doi.org/10.1080/03067319608028137.
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Molnár, Ágnes. "Estimation of volatile organic compounds (VOC) emission for Hungary." Atmospheric Environment. Part A. General Topics 24, no. 11 (1990): 2855–60. http://dx.doi.org/10.1016/0960-1686(90)90173-k.
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Hadi, Kasnawi Al, Arif Budianto, Sabila Alhadawiah, Karina Alma Fidya, and Satutik Rahayu. "VOCs (Volatile Organic Compounds) Concentration Measurement in Human-Exhaled Breath - A Preliminary Study." JURNAL SAINS TEKNOLOGI & LINGKUNGAN 10, no. 4 (2024): 618–22. https://doi.org/10.29303/jstl.v10i4.728.
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VOC is a group of organic compounds that easily evaporate into the atmosphere and have various impacts on human health and the environment. Human exhaled breath and VOC is related to each other. The concentration of VOC differs from an abnormal condition to other abnormalities. However, there is limited information or study about VOC concentration in human exhaled breath. In line with this, this study aims to develop a VOC meter or a measurement system using a CCS811 sensor for human exhaled breath. This study used a CCS811 sensor, a microcontroller, and a suction pump installed inside a sensor box. The system was calibrated using filtered and non-filtered air. The system was tested using varying flow rates. At the final test, the system was tested to measure VOC levels in human exhaled breaths. The results show that the VOC measurement system can measure VOC levels in different air conditions for both filtered and non-filtered air. The use of different flow rates influences the system's performance. The highest sensitivity level is obtained at 0.7 m/s of the flow rate of the suction pump. The system was also able to measure VOC concentrations of the human exhaled breath with concentrations of 0 ppb to 1156 ppb. The VOC concentrations of human exhaled breath depend on many factors that should be further analyzed, including the medical treatment history, food consumption, placebo effect, and many other parameters.
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Álvarez-García, Samuel, Sara Mayo-Prieto, Guzmán Carro-Huerga, et al. "Volatile Organic Compound Chamber: A Novel Technology for Microbiological Volatile Interaction Assays." Journal of Fungi 7, no. 4 (2021): 248. http://dx.doi.org/10.3390/jof7040248.
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The interest in the study of microbiological interactions mediated by volatile organic compounds (VOCs) has steadily increased in the last few years. Nevertheless, most assays still rely on the use of non-specific materials. We present a new tool, the volatile organic compound chamber (VOC chamber), specifically designed to perform these experiments. The novel devices were tested using four Trichoderma strains against Fusarium oxysporum and Rhizoctonia solani. We demonstrate that VOC chambers provide higher sensitivity and selectivity between treatments and higher homogeneity of results than the traditional method. VOC chambers are also able to test both vented and non-vented conditions. We prove that ventilation plays a very important role regarding volatile interactions, up to the point that some growth-inhibitory effects observed in closed environments switch to promoting ones when tested in vented conditions. This promoting activity seems to be related to the accumulation of squalene by T. harzianum. The VOC chambers proved to be an easy, homogeneous, flexible, and repeatable method, able to better select microorganisms with high biocontrol activity and to guide the future identification of new bioactive VOCs and their role in microbial interactions.
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Agho, C. A., E. Runno-Paurson, T. Tähtjärv, E. Kaurilind, and Ü. Niinemets. "Variation in Leaf Volatile Emissions in Potato (Solanum tuberosum) Cultivars with Different Late Blight Resistance." Plants 12, no. 11 (2023): 2100. http://dx.doi.org/10.3390/plants12112100.
Texte intégralRésumé :
Volatile organic compounds (VOCs) play key roles in plant abiotic and biotic stress resistance, but even for widespread crops, there is limited information on variations in the magnitude and composition of constitutive VOC emissions among cultivars with varying stress resistance. The foliage VOC emissions from nine local and commercial potato cultivars (Alouette, Sarme, Kuras, Ando, Anti, Jõgeva Kollane, Teele, 1681-11, and Reet) with medium to late maturities and varying Phytophthora infestans (the causative agent of late blight disease) resistance backgrounds were analyzed to gain an insight into the genetic diversity of constitutive VOC emissions and to test the hypothesis that cultivars more resistant to Phytophthora infestans have greater VOC emissions and different VOC fingerprints. Forty-six VOCs were identified in the emission blends of potato leaves. The majority of the VOCs were sesquiterpenes (50% of the total number of compounds and 0.5–36.9% of the total emissions) and monoterpenes (30.4% of the total number of compounds and 57.8–92.5% of the total VOC emissions). Qualitative differences in leaf volatiles, mainly in sesquiterpenes, were related to the potato genotype background. Among the volatile groups, the monoterpenes α-pinene, β-pinene, Δ3-carene, limonene, and p-cymene, the sesquiterpenes (E)-β-caryophyllene and α-copaene, and green leaf volatile hexanal were the major volatiles in all cultivars. A higher share of VOCs known to have antimicrobial activities was observed. Interestingly, the cultivars were grouped into high and low resistance categories based on the VOC profiles, and the total terpenoid and total constitutive VOC emission scale positively with resistance. To support and expedite advances in breeding for resistance to diseases such as late blight disease, the plant research community must develop a fast and precise approach to measure disease resistance. We conclude that the blend of emitted volatiles is a fast, non-invasive, and promising indicator to identify cultivars resistant to potato late blight disease.
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Webber, M. D., J. D. Goodin, P. J. A. Fowlie, R. L. Hong-You, and J. Legault. "Persistence of Volatile Organic Compounds in Sludge Treated Soils." Water Quality Research Journal 32, no. 3 (1997): 579–98. http://dx.doi.org/10.2166/wqrj.1997.034.
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Abstract Laboratory incubation studies were conducted to assess the persistence of ten volatile organic compounds (VOCs) in seven soils treated with 3% dw of anaer-obically digested municipal sludge. The VOCs were probable municipal sludge contaminants and the soils represented wide ranges of constituents likely to sorb organic compounds, e.g., organic carbon (1.3 to 12%) and clay (7 to 50%). The VOCs were spiked into soils at 50 mg kg-1 dw of soil, except for trichloro-ethylene and chloroform which were at 2.5 mg kg-1 dw. Three general patterns of VOC losses from soils were identified: (1) complete volatilization at room temperature within 24 h, (2) complete volatilization/degradation within 144 to 288 h, and (3) incomplete volatilization/degradation within 288 h. All VOC losses were consistent with first-order kinetics and indicated a combination of a rapid initial kinetic (0 to 4 h) followed by a slower kinetic. The slower kinetic was assumed to be more relevant to field VOC losses than the rapid kinetic, and first-order half-lives were calculated using the 4- to 288-h experimental data. The half-lives ranged from 5.5 to 1,926 h with a median value of 70 h, and generally increased with increasing boiling points of the VOCs and with increasing organic carbon contents of the soils. These laboratory findings indicate that VOCs in land-applied sludge are unlikely to represent a hazard to agriculture.
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Zhou, You, and Bing Yan. "A responsive MOF nanocomposite for decoding volatile organic compounds." Chemical Communications 52, no. 11 (2016): 2265–68. http://dx.doi.org/10.1039/c5cc09029f.
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A molecular decoding platform, which recognizes aromatic VOCs with distinctly different 2D readouts, has been developed by a responsive luminescent MOF nanocomposite. The VOC recognition is based on an unprecedented dual-readout orthogonal identification scheme.
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Fiorenza, Roberto. "Bimetallic Catalysts for Volatile Organic Compound Oxidation." Catalysts 10, no. 6 (2020): 661. http://dx.doi.org/10.3390/catal10060661.
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In recent years, the impending necessity to improve the quality of outdoor and indoor air has produced a constant increase of investigations in the methodologies to remove and/or to decrease the emission of volatile organic compounds (VOCs). Among the various strategies for VOC elimination, catalytic oxidation and recently photocatalytic oxidation are regarded as some of the most promising technologies for VOC total oxidation from urban and industrial waste streams. This work is focused on bimetallic supported catalysts, investigating systematically the progress and developments in the design of these materials. In particular, we highlight their advantages compared to those of their monometallic counterparts in terms of catalytic performance and physicochemical properties (catalytic stability and reusability). The formation of a synergistic effect between the two metals is the key feature of these particular catalysts. This review examines the state-of-the-art of a peculiar sector (the bimetallic systems) belonging to a wide area (i.e., the several catalysts used for VOC removal) with the aim to contribute to further increase the knowledge of the catalytic materials for VOC removal, stressing the promising potential applications of the bimetallic catalysts in the air purification.
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Chiemchaisri, Wilai, Chettiyappan Visvanathan, and Shing Wu Jy. "Effects of trace volatile organic compounds on methane oxidation." Brazilian Archives of Biology and Technology 44, no. 2 (2001): 135–40. http://dx.doi.org/10.1590/s1516-89132001000200005.
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The effects of volatile organic compounds (VOCs) on methane oxidation in landfill cover soils were examined. The batch experiments were conducted using single and mixed VOCs, such as, dichloromethane (DCM), trichloroethylene (TCE), tetrachloroethylene (PCE), and benzene. The results from all combinations showed a decrease in methane oxidation rate with increase in VOC concentrations. Moreover, inhibition effects of TCE and DCM were found higher than benzene and PCE. The reduction of methane oxidation by benzene and PCE could be attributed to the toxicity effect, whereas TCE and DCM were found to exhibit the competitive-inhibition effect. When the soil was mixed with DCM, no methane oxidation was found. Damage to the cell’s internal membrane was found in a methanotrophic culture exposed to VOC gases which is the attachment site of a key enzyme needed for methane oxidation
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el Manouni el Hassani, Sofia, Hendrik Niemarkt, Hager Said, et al. "Fecal Volatile Organic Compounds in Preterm Infants Are Influenced by Enteral Feeding Composition." Sensors 18, no. 9 (2018): 3037. http://dx.doi.org/10.3390/s18093037.
Texte intégralRésumé :
Fecal volatile organic compound (VOC) analysis has shown great potential as a noninvasive diagnostic biomarker for a variety of diseases. Before clinical implementation, the factors influencing the outcome of VOC analysis need to be assessed. Recent studies found that the sampling conditions can influence the outcome of VOC analysis. However, the dietary influences remains unknown, especially in (preterm) infants. Therefore, we assessed the effects of feeding composition on fecal VOC patterns of preterm infants (born at <30 weeks gestation). Two subgroups were defined: (1) daily intake >75% breastmilk (BM) feeding and (2) daily intake >75% formula milk (FM) feeding. Fecal samples, which were collected at 7, 14 and 21 days postnatally, were analyzed by an electronic nose device (Cyranose 320®). In total, 30 preterm infants were included (15 FM, 15 BM). No differences in the fecal VOC patterns were observed at the three predefined time-points. Combining the fecal VOC profiles of these time-points resulted in a statistically significant difference between the two subgroups although this discriminative accuracy was only modest (AUC [95% CI]; p-value; sensitivity; and specificity of 0.64 [0.51–0.77]; 0.04; 68%; and 51%, respectively). Our results suggest that the influence of enteral feeding on the outcome of fecal VOC analysis cannot be ignored in this population. Furthermore, in both subgroups, the fecal VOC patterns showed a stable longitudinal course within the first month of life.
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Musyanovych, Anna, Christoph Grimmer, Ali Enis SADAK, et al. "Polymer Capsules with Volatile Organic Compounds as Reference Materials for Controlled Emission." ACS Applied Materials and Interfaces 16, no. 50 (2024): 69999−70009. https://doi.org/10.1021/acsami.4c12826.
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Encapsulation of volatile organic compounds (VOCs) that could evaporate at a defined rate is of immense interest for application in emission reference materials (ERMs). Polyurethane/polyurea microcapsules with various VOC active ingredients (limonene, pinene, and toluene) were successfully produced by interfacial polymerization with Shirasu porous glass membrane emulsification in a size range between 10 and 50 μm. The effect of surfactant, VOC, monomer(s) type, and ratio has a great effect on the formulation process and morphology of capsules. The type of VOC played a significant role in the encapsulation efficiency. Due to the difference in vapor pressure and VOC/water interfacial tension, the formulation for encapsulation was optimized for each individual VOC. Furthermore, to achieve effective stability of the large droplets/capsules, a combination of ionic and nonionic surfactants was used. Optical and scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), were used to characterize the optimized microcapsules. The results showed that the obtained microcapsules exhibited a spherical shape and core−shell morphology and featured characteristic urethane-urea bonds. The amount of encapsulated VOC ranges between 54 and 7 wt %. The emission tests were performed with the help of the emission test chamber procedure (EN 16516). The limonene-loaded polyurethane/polyurea microcapsules show a change in emission rate of less than 10% within 14 days and can be considered as a potential candidate for use as an ERM.
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Bitas, Vasileios, Hye-Seon Kim, Joan W. Bennett, and Seogchan Kang. "Sniffing on Microbes: Diverse Roles of Microbial Volatile Organic Compounds in Plant Health." Molecular Plant-Microbe Interactions® 26, no. 8 (2013): 835–43. http://dx.doi.org/10.1094/mpmi-10-12-0249-cr.
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Secreted proteins and metabolites play diverse and critical roles in organismal and organism–environment interactions. Volatile organic compounds (VOC) can travel far from the point of production through the atmosphere, porous soils, and liquid, making them ideal info-chemicals for mediating both short- and long-distance intercellular and organismal interactions. Critical ecological roles for animal- and plant-derived VOC in directing animal behaviors and for VOC as a language for plant-to-plant communication and regulators of various physiological processes have been well documented. Similarly, microbial VOC appear to be involved in antagonism, mutualism, intra- and interspecies regulation of cellular and developmental processes, and modification of their surrounding environments. However, the available knowledge of how microbial VOC affect other organisms is very limited. Evidence supporting diverse roles of microbial VOC with the focus on their impact on plant health is reviewed here. Given the vast diversity of microbes in nature and the critical importance of microbial communities associated with plants for their ecology and fitness, systematic exploration of microbial VOC and characterization of their biological functions and ecological roles will likely uncover novel mechanisms for controlling diverse biological processes critical to plant health and will also offer tangible practical benefits in addressing agricultural and environmental problems.
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Suresh, Karantothu, Chetna, Raj Kumar Mandal, Dasari Purna Prakash, Kakadi Akhil Dora, and J. M. Kavana. "The Role of Volatile Organic Compounds (VOCs) in Determining Seed Physiological Quality: A Review." International Journal of Environment and Climate Change 14, no. 9 (2024): 124–38. http://dx.doi.org/10.9734/ijecc/2024/v14i94398.
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Volatile organic compounds (VOCs) emitted by seeds serve as promising biomarkers for assessing seed vigor, viability, and deterioration during storage. This review synthesizes current knowledge on the types and chemical classes of VOCs released by seeds, factors affecting their emission, and methods for their collection and analysis. VOCs indicate seed aging, with increased emissions of alcohols, aldehydes, and ketones associated with deterioration processes like lipid peroxidation. Volatile organic compounds (VOCs) associated with seed deterioration include alcohols like ethanol, which can indicate fermentation, aldehydes such as hexanal, which is linked to lipid oxidation, and ketones like 2-heptanone, which can result from microbial activity and contribute to off-flavors and rancidity. The quantity and composition of VOCs correlate with the extent of seed deterioration, potentially offering a rapid, non-destructive alternative to traditional germination tests for evaluating seed quality. VOCs also mediate interactions between seeds and microorganisms, influencing germination and stress responses. Different research findings regarding volatile organic compounds (VOCs) in seeds indicate their potential as indicators of seed quality, which could lead to improved seed management strategies. By utilizing VOC profiling, farmers can make informed decisions on seed selection and treatment, ultimately enhancing crop yield and resilience in agricultural practices. While VOC analysis shows promise for integration into seed quality testing, challenges remain in standardizing protocols and identifying robust markers across different seed types, species and storage conditions. Advances in VOC research may ultimately lead to novel solutions for improving seed and crop productivity. Future research directions in VOC analysis for seed quality testing should focus on standardizing VOC profiles across diverse seed species, integrating VOC analysis with precision agriculture technologies, exploring environmental influences on VOC emissions, developing non-invasive testing methods, conducting longitudinal studies on seed storage, applying VOCs in breeding programs, and establishing links between VOC emissions and disease resistance.
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Fillmore, Randolph. "Waterborne Resins for Direct-to-Metal Coatings." Materials Performance 47, no. 3 (2008): 44–45. https://doi.org/10.5006/mp2008_47_3-44.
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Industrial users and governmental bodies are seeking high-durability industrial coatings that emit low levels of volatile organic compounds (VDCs). The coming years will likely bring change from high VOC solvent-borne coatings to waterborne coatings with low VOC emissions. Water-based, low-VOC, highly durable coatings for metal are being produced.
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Malone, Shealyn C., David K. Weaver, Tim F. Seipel, et al. "Herbivore-induced volatile emissions are altered by soil legacy effects in cereal cropping systems." Plant and Soil 455, no. 1-2 (2020): 171–86. http://dx.doi.org/10.1007/s11104-020-04674-2.
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Abstract Aims (main purpose and research question) Soil properties, including microbial composition and nutrient availability, can influence the emissions of plant volatile organic compounds (VOCs) that serve as host-location cues for insect pests and their natural enemies. Agricultural practices have profound effects on soil properties, but how these influence crop VOCs remains largely unknown. The aim of this study was to investigate the effect of agricultural practices on constitutive and herbivore-induced VOC emissions by a major staple crop through soil legacy effects. Methods In a full factorial experiment, we measured VOC emissions by wheat (Triticum aestivum) grown in soil inoculum from wheat-fallow or wheat-cover crop rotations that was subjected to feeding by larval Cephus cinctus. Results (main findings) Under herbivory, plants grown in cover crop inoculum emitted greater total VOCs, including higher concentrations of 2-pentadecanone, an insect repellent, and nonanal, a compound important in the recruitment of natural enemies. Plants grown in fallow inoculum showed no differences in emissions whether under herbivory or not. Soil inoculum did not influence VOC emissions of plants in the absence of larval feeding. Conclusions These results suggest that agricultural practices influence crop VOC emissions through soil legacy effects. Additionally, crops grown in wheat-fallow rotations may be less successful recruiting natural enemies of pests through herbivore-induced VOC signaling. Abbreviations Volatile organic compounds (VOCs); herbivore-induced plant volatiles (HIPV); green leaf volatiles (GLVs); northern Great Plains (NGP); wheat stem sawfly (WSS); gas chromatography-mass spectrometry (GC-MS); non-metric multidimensional scaling (NMDS); generalized linear mixed-effects model (GLMM).
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Peera, Asghar, and Vania Buzatto. "Sustainable Materials: The New Bottom Line in Paint and Coatings." CoatingsPro 15, no. 2 (2015): 24–26. https://doi.org/10.5006/cp2015_15_2-24.
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Jure, Pohleven, David Burnard Michael, and Kutnar Andreja. "Volatile organic compounds emitted from untreated and thermally modified wood - a review." Wood and fiber science 51, no. 3 (2019): 1–24. https://doi.org/10.22382/wfs-2019-023.
Texte intégralRésumé :
Volatile organic compounds (VOCs) are a diverse group of compounds that can have a strong impact on indoor air quality.Wood and thermally modified wood emit VOCs, which are referred to as wood VOCs, and can elicit various negative or positive effects in different organisms, including humans. Wood is a complex multicomponent biopolymer with inherent variability, which is also reflected in the emissions of VOCs. Variability in wood VOC emissions has been attributed to endogenous and exogenous factors, such as wood species, type of wood sample, wood treatment, etc. Nevertheless, studies have reported reasonably consistent results regarding VOC emissions from individual (thermally modified) wood species. Softwoods emit the highest concentrations of wood VOCs composed primarily of volatile terpene emissions (70-90%) and lower concentrations of hexanal and acetic acid (10-25%). VOC emissions from hardwoods are considerably lower (approximately 50 times) and include hexanal and pentanal, acetic acid, as well as other VOCs formed during wood degradation processes, but not volatile terpenes. Total VOC emissions from softwoods are reduced following thermal treatment, whereas emissions are increased from hardwoods after thermal treatment. In thermally treated softwoods, emissions of volatile terpenes and hexanal are drastically decreased, whereas those of acetic acid and furfural increase. Similarly, in thermally treated hardwoods, the emissions of hexanal and pentanal are reduced, whereas acetic acid and furfural, as well as other compounds increase. In addition, formaldehyde emissions are ubiquitous, albeit at low concentrations, but increase following heat treatment. Furthermore, the number of VOCs emitted from thermally treated wood increases with heat treatment temperature. This review article will help guide future research, particularly the evaluation of the impact of different wood species on indoor air quality and the development ofmodification techniques that target extraction or suppression of VOCemissions.
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Umarani, R., M. Bhaskaran, C. Vanitha, and M. Tilak. "Fingerprinting of volatile organic compounds for quick assessment of vigour status of seeds." Seed Science Research 30, no. 2 (2020): 112–21. http://dx.doi.org/10.1017/s0960258520000252.
Texte intégralRésumé :
AbstractSeed is a fertilized mature ovule, which possesses an embryonic plant. When the dry, mature seeds are subjected to imbibition, they release a wide range of organic substances, which include low molecular weight carbonyl compounds (gases and volatiles) and water-soluble organic substances (enzymes and polysaccharides). The volatile organic compounds (VOCs) are molecules of low molecular weight (300 g mol−1) and high vapour pressure (0.01 kPa at 20°C) and include diverse chemical compounds. The nature and emission kinetics of volatiles produced from seeds vary, depending on the moisture content of the seeds. Orthodox seeds stored at ‘low seed moisture content’ undergo seed deterioration, predominantly due to lipid peroxidation, initiated by autoxidation or enzymatic oxidation of unsaturated or polyunsaturated fatty acids. This peroxidation leads to emission of volatile compounds. The quantity of VOCs emitted is positively correlated with the advancement of seed deterioration. With respect to the seed germination process, exposure of seeds to ‘high moisture conditions’ leads to increased respiration, triggers glycolysis and mobilization of storage reserves, resulting in the emission of volatile metabolic products. The quantity of VOCs emitted on commencement of metabolic activity in germinating seeds depends on (1) vigour status and (2) amount of storage reserves. Since it has been established that there is a significant difference between high and low vigour seeds with respect to quantity and profile of VOCs emitted, there is great potential for utilizing the VOC profile to obtain a quick and reproducible test of vigour status of crop seeds. In order to harness the VOC profile for quick assessment of vigour status of seeds, research has to be taken up to develop standard protocols for fingerprinting of VOCs for the purpose of seed vigour assessment and to fix the standard volatile biomarker(s) specific to crop and vigour status of seeds.
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Zhang, Ruishan, Zihao Wang, Qihua Hou, et al. "First-principles insights into the C6N7 monolayer as a highly efficient sensor and scavenger for the detection of selective volatile organic compounds." RSC Advances 13, no. 41 (2023): 28703–12. http://dx.doi.org/10.1039/d3ra05573f.
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Sun, Shi Jing, and Jun Shen. "Study on Reducing the Volatile Organic Compounds Emissions from Different Processing Particleboards." Advanced Materials Research 113-116 (June 2010): 1101–5. http://dx.doi.org/10.4028/www.scientific.net/amr.113-116.1101.
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The aim of this paper is to study on how to control VOC emissions from wood-based panel manufacturing. Total volatile organic compounds (TVOC) emissions from larch particleboard under different processing conditions were collected by an environmental chamber. VOC samples were prepared by desiccator, adsorbed by activated carbon, desorpted with Methylene dichloride and measured by GC/MS. The result showed that the optimal process parameters were single-layer structure, moisture content of 6%, density of 0.60 g•cm-3, thickness of 8mm, resin content of 7%, hot-pressing time of 4min.TVOC increased with board density going up，hot-pressing time increasing, moisture content and resin content rising. The predominant compounds emissions from the particleboards are aromatic compound and hydrocarbon. 24 kinds of compounds were identified from the standard board. With hydrocarbon decreasing, aromatic VOC type increased.
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Rondanelli, Mariangela, Federica Perdoni, Vittoria Infantino, et al. "Volatile Organic Compounds as Biomarkers of Gastrointestinal Diseases and Nutritional Status." Journal of Analytical Methods in Chemistry 2019 (September 10, 2019): 1–14. http://dx.doi.org/10.1155/2019/7247802.
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Purpose. The purpose of this review was to identify the best solution for rapid and noninvasive diagnosis and long-term monitoring of patients affected by inflammatory gastrointestinal diseases, colon and gastric cancer, obesity in correlation to diet, and breast milk to evaluate exposure to VOCs in women and infants. Methods. This review included 20 previously published eligible studies. VOC analysis has allowed us to highlight differences in lifestyles, intestinal microbiota, and metabolism. New innovative methods have been described that allow the detection and quantification of a broad spectrum of metabolites present in exhaled breath even at very low levels, some of which have been shown to be indicators of pathological conditions. Results. Five studies were analyzed that involved VOC analysis in relation to type of diet. All of them showed that the type of diet can have an impact on metabolites excreted and therefore can be a useful tool in the nutritional studies related to metabolism and health and disease status. Two studies concerned VOC analysis in inflammatory bowel diseases, and the results showed that VOCs can distinguish active disease from remission; VOC profile is clearly different in patients. In particular, C15H30 1-pentadecene, 3-methyl-1-butanal, octane, acetic acid, alpha-pinene, and m-cymene are elevated in active ulcerative colitis. Four studies examined VOCs in gastric and colorectal tumors showing a change in metabolic biomarkers of cancer patients compared to the control group. Finally, the study of VOCs in breast milk has improved the understanding of the potential health risks of exposure of children to chemical pollutants. Conclusions. VOC analysis allowed to highlight differences in behavior, lifestyle, and metabolism of individuals. Analytical methods are continuously developed to allow for better detection and quantification of metabolites, thus enabling the detection of a broader spectrum of pathophysiology and disease biomarkers.
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Saarikoski, Sanna, Heidi Hellén, Arnaud P. Praplan, et al. "Characterization of volatile organic compounds and submicron organic aerosol in a traffic environment." Atmospheric Chemistry and Physics 23, no. 5 (2023): 2963–82. http://dx.doi.org/10.5194/acp-23-2963-2023.
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Abstract. Urban air consists of a complex mixture of gaseous and particulate species from anthropogenic and biogenic sources that are further processed in the atmosphere. This study investigated the characteristics and sources of volatile organic compounds (VOCs) and submicron organic aerosol (OA) in a traffic environment in Helsinki, Finland, in late summer. The anthropogenic VOCs (aVOCs; aromatic hydrocarbons) and biogenic VOCs (bVOCs; terpenoids) relevant for secondary-organic-aerosol formation were analyzed with an online gas chromatograph mass spectrometer, whereas the composition and size distribution of submicron particles was measured with a soot particle aerosol mass spectrometer. This study showed that aVOC concentrations were significantly higher than bVOC concentrations in the traffic environment. The largest aVOC concentrations were measured for toluene (campaign average of 1630 ng m−3) and p/m xylene (campaign average of 1070 ng m−3), while the dominating bVOC was α-pinene (campaign average of 200 ng m−3). For particle-phase organics, the campaign-average OA concentration was 2.4 µg m−3. The source apportionment analysis extracted six factors for OA. Three OA factors were related to primary OA sources – traffic (24 % of OA, two OA types) and a coffee roastery (7 % of OA) – whereas the largest fraction of OA (69 %) consisted of oxygenated OA (OOA). OOA was divided into less oxidized semi-volatile OA (SV-OOA; 40 % of OA) and two types of low-volatility OA (LV-OOA; 30 %). The focus of this research was also on the oxidation potential of the measured VOCs and the association between VOCs and OA in ambient air. Production rates of the oxidized compounds (OxPR) from the VOC reactions revealed that the main local sources of the oxidation products were O3 oxidation of bVOCs (66 % of total OxPR) and OH radical oxidation of aVOCs and bVOCs (25 % of total OxPR). Overall, aVOCs produced a much smaller portion of the oxidation products (18 %) than bVOCs (82 %). In terms of OA factors, SV-OOA was likely to originate from biogenic sources since it correlated with an oxidation product of monoterpene, nopinone. LV-OOA consisted of highly oxygenated long-range or regionally transported OA that had no correlation with local oxidant concentrations as it had already spent several days in the atmosphere before reaching the measurement site. In general, the main sources were different for VOCs and OA in the traffic environment. Vehicle emissions impacted both VOC and OA concentrations. Due to the specific VOCs attributed to biogenic emissions, the influence of biogenic emissions was more clearly detected in the VOC concentrations than in OA. In contrast, the emissions from the local coffee roastery had a distinctive mass spectrum for OA, but they could not be seen in the VOC measurements due to the measurement limitations for the large VOC compounds. Long-range transport increased the OA concentration and oxidation state considerably, while its effect was observed less clearly in the VOC measurements due to the oxidation of most VOC in the atmosphere during the transport. Overall, this study revealed that in order to properly characterize the impact of different emission sources on air quality, health, and climate, it is of importance to describe both gaseous and particulate emissions and understand how they interact as well as their phase transfers in the atmosphere during the aging process.
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Pedrini, Alessandro, Angelo Maspero, Silvia Bracco, et al. "Synthesis, crystal structure, and optical properties of fluorinated poly(pyrazole) ligands and in silico assessment of their affinity for volatile organic compounds." New Journal of Chemistry 44, no. 16 (2020): 6443–55. http://dx.doi.org/10.1039/d0nj00259c.
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Increasing fluorination of an organic ligand forming porous coordination polymers results in enhanced affinity for volatile organic compounds (VOCs) without affecting the fluorescence properties, thus opening new perspectives for VOC sensing.
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Novitsky, E. G., P. O. Tokarev, Yu I. Matveeva, V. V. Volkov, and E. A. Grushevenko. "Capture and Recovery of Volatile Organic Compounds Vapors Using Membrane Technology." Membrany i membrannye tehnologii 14, no. 4 (2024): 249–62. http://dx.doi.org/10.31857/s2218117224040017.
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The problem of separation and recovery of volatile organic compounds (VOC) vapors is important both from the point of view of reducing the negative anthropogenic impact on the environment and from the point of view of resource conservation. The main classes of VOCs are, first of all, aliphatic, aromatic and oxygen-containing hydrocarbons. A significant source of VOC emissions of various natures are waste gas process flows (or off-gases) of petrochemical industries (polymerization processes, hydrotreating, isomerization, dehydrogenation, etc.). The capture and recovery of VOC vapors is implemented mainly using recovery technology and decomposition technology. This review is devoted to a brief overview of modern technologies for the removal and recovery of VOCs from vapor-gas mixtures. The technology of membrane separation of vapor-gas mixtures, including promising membrane materials, is considered in detail. This technology allows for the selective separation of VOCs, and the purified main gas flow can be returned to the production cycle, if necessary, without additional preparation.
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Pui, Wee Kong, Rozita Yusoff, and Mohamed Kheireddine Aroua. "A review on activated carbon adsorption for volatile organic compounds (VOCs)." Reviews in Chemical Engineering 35, no. 5 (2019): 649–68. http://dx.doi.org/10.1515/revce-2017-0057.
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Abstract A number of control methods have been adopted for the removal of hazardous volatile organic compounds (VOCs) from gas streams, particularly adsorption processes which are considered more prominent in terms of feasibility, effectiveness as well as cost competence compared to other methods. In this study, most of the activated-carbon-based adsorbents are critically reviewed in terms of their advantages and limitations for VOC gas adsorption. The choice of adsorbent and process parameters depends mainly on the type of VOC used, its chemical and structural properties, in addition to the adsorbent’s characteristics. The review discusses in detail the application of fixed-bed adsorption systems. A computational simulation study using quantum-chemical conductor like screening model for real solvents is included in this review which determines the efficiency in describing and predicting the adsorption technique required for each process. This review offers a comprehensive discussion of the VOC adsorption techniques and their implementation for different applications.
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Wu, Shu Yun, Zeng Feng Yan, Jun Gang Dong, and Huan Huan Liu. "Research of the Distribution of Volatile Organic Compounds (VOC) in Print Shops in Xi’an." Applied Mechanics and Materials 209-211 (October 2012): 1560–65. http://dx.doi.org/10.4028/www.scientific.net/amm.209-211.1560.
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Volatile organic compounds (VOCs) are major constituents of the indoor air pollutants. The indoor air quality has caused wide concern for VOCs may affect human health in many ways. The VOCs in general rooms volatilize from building materials, furniture and so on. In print shops the print equipment and materials may produce a large amount of VOCs that may affect the health of the long-term print shop workers. The author has measured the VOC content and the air indexes in a seventy square-meter print shop in Xi’an with comprehensive functions, then, evaluated the pollution and proposed the preventions of the VOC content in print shops.
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Vargas, Victor, Marie-Cecile Chalbot, Robert O'Brien, et al. "The effect of anthropogenic volatile organic compound sources on ozone in Boise, Idaho." Environmental Chemistry 11, no. 4 (2014): 445. http://dx.doi.org/10.1071/en13150.
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Environmental context Volatile organic compounds are precursors of ozone, a pollutant with adverse environmental effects. It is important to determine the associations between the various sources of volatile organic compounds and ozone levels because emission controls are based on sources. We estimated the contributions of specific sources of volatile organic compounds on ozone levels using both measurements and statistical models, and found that traffic is the largest source even in events when wildfire smoke is present. Abstract Here, we present the application of a tiered approach to apportion the contributions of volatile organic compound (VOC) sources on ozone (O3) concentrations. VOCs from acetylene to n-propylbenzene were measured at two sites at Boise, Idaho, using an online pneumatically focussed gas chromatography system. The mean 24-h concentrations of individual VOCs varied from 0.4ppbC (parts per billion carbon) for 1-butene to 23.2ppbC for m- and p-xylene. The VOC sources at the two monitoring sites were determined by positive matrix factorisation. They were attributed to: (i) liquefied petroleum and natural gas (LPG/NG) emissions; (ii) fugitive emissions of olefins from fuel and solvents; (iii) fugitive emissions of aromatic VOCs from area sources and (iv) vehicular emissions. Vehicle exhausts accounted for 36 to 45% of VOCs followed by LPG/NG and fugitive emissions of aromatic VOCs. Evaluation of photochemical changes showed that the four separate VOC sources were identified by PMF rather than different stages of photochemical processing of fresh emissions. The contributions of VOC sources on daily 8-h maximum O3 concentrations measured at seven locations in the metropolitan urban area were identified by regression analysis. The four VOC sources added, on average, 6.4 to 16.5 parts per billion by volume (ppbv) O3, whereas the unexplained (i.e. intercept) O3 was comparable to non-wildfire policy-relevant background O3 levels in the absence of all anthropogenic emissions of VOC precursors in North America for the region. Traffic was the most significant source influencing O3 levels contributing up to 32ppbv for days with O3 concentrations higher than 75ppbv.
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Kleeblatt, Juliane, Benjamin Stengel, Christian Radischat, et al. "Needle trap sampling thermal-desorption resonance enhanced multiphoton ionization time-of-flight mass spectrometry for analysis of marine diesel engine exhaust." Analytical Methods 7, no. 8 (2015): 3608–17. http://dx.doi.org/10.1039/c5ay00321k.
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Lim, M., and A. R. Lea-Langton. "Simulation of ozonolysis of volatile organic compounds: Effect on flue gas composition." IOP Conference Series: Materials Science and Engineering 1195, no. 1 (2021): 012012. http://dx.doi.org/10.1088/1757-899x/1195/1/012012.
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Abstract This study shows that the reaction of ozone with various volatile organic compounds (VOC) yields different flue gas composition in terms of the carbon dioxide, oxygen and moisture contents. Steam production and thermal output requirements from a combustion system (i.e., a boiler) may dictate the range of operating conditions, such as the air to fuel mass flow rates. To improve the combustion efficiency in these operating conditions, low temperature plasmas have been used to ionize air and generate ozone as an oxidant for ozonolysis with the VOC. Therefore, this study simulates the reaction mechanism of the ozonolysis of VOC and the effect on the flue gas composition, which affects the combustion efficiency. Simulation results show that residual oxygen in the flue gas reduces, reducing the excess air. Thus, the corresponding efficiency loss through dry flue gas would be reduced. Literature data shows that emissions of alkanes, alkynes and alkenes per unit mass of solid fuel is evident for both coal and biomass, and thus ozonolysis of these VOC would reduce the excess air, improving the combustion efficiency.
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Zhang, Hong Hua, Shao Peng Wu, Ling Pang, Kim Jenkins, Man Yu, and Pei Qiang Cui. "Grey System Theoretical Analysis on the Influence of Volatile Organic Compounds Emission from Asphalt on its Performance." Advanced Materials Research 753-755 (August 2013): 481–85. http://dx.doi.org/10.4028/www.scientific.net/amr.753-755.481.
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Light components in the asphalt can volatilize under the circumstances of high temperature or long-term service process, leading to the deteriorating of the asphalt pavement. This paper tried to discuss the influences of volatile organic compounds (VOC) emission from the asphalt on physical properties in the high temperature (at 180) by grey system theory. Both Heat and Vacuum environment were monitored as the emission conditions and the emission temperature was 180°C, physical properties of asphalt, released and unreleased were analyzed. Basic tests, including mass change, chemical compositions, penetration and soften point, were used to compare the influences of VOC emission on the asphalts performances. Meanwhile, grey system theory was used to investigate the sequent performances influenced by VOC emission. Results show that physical properties and four generic components of the asphalts are affected obviously in these two emission conditions, and the oxygen may promote VOC emission from the asphalt. In additional, the greatest factor associating with VOC emission is light components in the asphalt.
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Shammay, A., I. Evanson, and R. M. Stuetz. "A comparison of removal performance of volatile organic and sulfurous compounds between odour abatement systems." Water Science and Technology 77, no. 11 (2018): 2657–67. http://dx.doi.org/10.2166/wst.2018.223.
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Abstract Three types of odour abatement systems in sewer networks in Australia were studied for 18 months to determine the removals of different compounds. Six volatile sulfurous compounds and seven volatile organic compounds (VOCs) were further investigated. All types of odour abatement systems exhibited good removal of hydrogen sulfide with the biotrickling filters (BTFs) showing the highest consistent removal. Biofilters outperformed BTFs and activated carbon (AC) filters in the removal of dimethyl mono-, di- and tri-sulfide species at the low inlet concentrations typically found. AC filters exhibited little VOC removal with no compound consistently identified as having a removal greater than 0%. Biofilters outperformed BTFs in VOC removal, yet both had high removal variability.
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Čech, Petr. "Influence of adhesive bonding on quantity of emissions VOCs." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 56, no. 4 (2008): 29–36. http://dx.doi.org/10.11118/actaun200856040029.
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The study deals with the influence of urea-formaldehyde glue and veneered bolstering on technological operation veneering on quantity of emission VOCs (volatile organic compounds).The so-called Volatile Organic Compounds (VOC) are among the largest pollution sources of both the internal and external environments.VOC is defined as emission of any organic compound or a mixture thereof, with the exception of methane, whereby the compound exerts the pressure of 0.01 kPa or more at the temperature of 20 °C (293.15 K) and reaches the corresponding volatility under the specific conditions of its use and can undergo photochemical reactions with nitrogen oxides when exposed to solar radiation.The effects of VOC upon environment can be described by equation:VOC + NOx + UV radiation + heat = tropospheric ozone (O3).In this work there were tested background working environment in various parts of multi-storeyed press, next was judged emissive charge of veneered device and used glue. We used surface material such as chipboard. We used urea-formaldehyde glue KRONOCOL U300 on technological operation veneering.The VOC emissions from the wooden surfaces with or without finishing were tested in the Equipment for VOC Measuring with a small-space chamber. This equipment was installed in and made available by the Institute of Furniture, Design and Habitation. The small-space chamber is suitable for testing small parts of wood products. The device equipped with small-chamber satisfies all conditions mandated in the standard ENV 13 419 DIN -V-ENV 13 419 ”Determination of the emissions of Volatile organic compounds”.The VOC emissions were collected in columns with sorbent Tenax TA. We analyzed the columns with the VOC emissions by: the gas chromatography in conjunction with mass spectrometer and Direct Thermal Desorption.
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Murphy, J. G., D. E. Oram, and C. E. Reeves. "Measurements of volatile organic compounds over West Africa." Atmospheric Chemistry and Physics 10, no. 12 (2010): 5281–94. http://dx.doi.org/10.5194/acp-10-5281-2010.
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Abstract. In this paper we describe measurements of volatile organic compounds (VOC) made using a Proton Transfer Reaction Mass Spectrometer (PTR-MS) aboard the UK Facility for Atmospheric Airborne Measurements during the African Monsoon Multidisciplinary Analyses (AMMA) campaign. Observations were made during approximately 85 h of flying time between 17 July and 17 August 2006, above an area between 4° N and 18° N and 3° W and 4° E, encompassing ocean, mosaic forest, and the Sahel desert. High time resolution observations of counts at mass to charge (m/z) ratios of 42, 59, 69, 71, and 79 were used to calculate mixing ratios of acetonitrile, acetone, isoprene, the sum of methyl vinyl ketone and methacrolein, and benzene respectively using laboratory-derived humidity-dependent calibration factors. Strong spatial associations between vegetation and isoprene and its oxidation products were observed in the boundary layer, consistent with biogenic emissions followed by rapid atmospheric oxidation. Acetonitrile, benzene, and acetone were all enhanced in airmasses which had been heavily influenced by biomass burning. Benzene and acetone were also elevated in airmasses with urban influence from cities such as Lagos, Cotonou, and Niamey. The observations provide evidence that both deep convection and mixing associated with fair-weather cumulus were responsible for vertical redistribution of VOC emitted from the surface. Profiles over the ocean showed a depletion of acetone in the marine boundary layer, but no significant decrease for acetonitrile.