Acceder

Bibliografías temáticas / OPAHs / Artículos de revistas

Siga este enlace para ver otros tipos de publicaciones sobre el tema: OPAHs.

Artículos de revistas sobre el tema "OPAHs"

Autor: Grafiati

Publicado: 1 de junio de 2024

Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros

Elija tipo de fuente:

Consulte los 50 mejores artículos de revistas para su investigación sobre el tema "OPAHs".

Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.

También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.

Explore artículos de revistas sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.

1

Jo, Jungmin, Ji-Yi Lee, Kyoung-Soon Jang, Atsushi Matsuki, Amgalan Natsagdorj y Yun-Gyong Ahn. "Development of Quantitative Chemical Ionization Using Gas Chromatography/Mass Spectrometry and Gas Chromatography/Tandem Mass Spectrometry for Ambient Nitro- and Oxy-PAHs and Its Applications". Molecules 28, n.º 2 (12 de enero de 2023): 775. http://dx.doi.org/10.3390/molecules28020775.

Texto completo

Resumen

The concentration of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere has been continually monitored since their toxicity became known, whereas nitro-PAHs (NPAHs) and oxy-PAHs (OPAHs), which are derivatives of PAHs by primary emissions or secondary formations in the atmosphere, have gained attention more recently. In this study, a method for the quantification of 18 NPAH and OPAH congeners in the atmosphere based on combined applications of gas chromatography coupled with chemical ionization mass spectrometry is presented. A high sensitivity and selectivity for the quantification of individual NPAH and OPAH congeners without sample preparations from the extract of aerosol samples were achieved using negative chemical ionization (NCI/MS) or positive chemical ionization tandem mass spectrometry (PCI-MS/MS). This analytical method was validated and applied to the aerosol samples collected from three regions in Northeast Asia—namely, Noto, Seoul, and Ulaanbaatar—from 15 December 2020 to 17 January 2021. The ranges of the method detection limits (MDLs) of the NPAHs and OPAHs for the analytical method were from 0.272 to 3.494 pg/m3 and 0.977 to 13.345 pg/m3, respectively. Among the three regions, Ulaanbaatar had the highest total mean concentration of NPAHs and OPAHs at 313.803 ± 176.349 ng/m3. The contribution of individual NPAHs and OPAHs in the total concentration differed according to the regional emission characteristics. As a result of the aerosol samples when the developed method was applied, the concentrations of NPAHs and OPAHs were quantified in the ranges of 0.016~3.659 ng/m3 and 0.002~201.704 ng/m3, respectively. It was concluded that the method could be utilized for the quantification of NPAHs and OPAHs over a wide concentration range.

Los estilos APA, Harvard, Vancouver, ISO, etc.

2

Teng, Chong, Shimin Wu, Yaqing Sun y Guangyi Gong. "Determination of Parent and Oxygenated Polycyclic Aromatic Hydrocarbons (PAHs) in Waste Cooking Oil and Oil Deodorizer Distillate by GC–QQQ–MS". Journal of AOAC International 102, n.º 6 (1 de noviembre de 2019): 1884–91. http://dx.doi.org/10.5740/jaoacint.19-0085.

Texto completo

Resumen

Background: Polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs (OPAHs) are classes of contaminants that are present in the environment and food. They pose a great threat to human health because of their carcinogenicity and mutagenicity. Very few studies have focused on their concentration in waste cooking oil (WCO) and oil deodorizer distillate (ODD). Objective: This study aimed (1) to design a reliable method to determine 16 PAHs and 4 OPAHs in both WCO and ODD and (2) to determine and analyze PAH and OPAH concentrations in actual samples to provide references for further research. Method: The PAH determination approach included double liquid–liquid extraction, double solid-phase extraction, and GC–triple quadrupole tandem MS determination. Oxidation indices were determined by titrimetry. Results: The method reached good linearity (R2 > 0.99) and an acceptable recovery rate (55.01–126.16% for WCO and 57.48–128.97% for ODD). Ten WCO and five ODD samples were determined, and the total concentration of 16 PAHs varied from 16.34 to 239.01 and 101.08 to 198.04 μg/kg in WCO and ODD, respectively. Among the 16 PAHs, three-ring PAHs typically contributed the most. It was also found that the acid value has a strong correlation with the concentration of OPAHs, probably because of the contribution of free fatty acids to OPAH formation. Conclusions: The proposed method was effective in the analysis of PAHs and OPAHs in WCO and ODD.

Los estilos APA, Harvard, Vancouver, ISO, etc.

3

Teng, Chong, Shimin Wu, Yaqing Sun y Guangyi Gong. "Determination of Parent and Oxygenated Polycyclic Aromatic Hydrocarbons (PAHs) in Waste Cooking Oil and Oil Deodorizer Distillate by GC–QQQ–MS". Journal of AOAC INTERNATIONAL 102, n.º 6 (1 de noviembre de 2019): 1884–91. http://dx.doi.org/10.1093/jaoac/102.6.1884.

Texto completo

Resumen

Abstract Background: Polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs (OPAHs) are classes of contaminants that are present in the environment and food. They pose a great threat to human health because of their carcinogenicity and mutagenicity. Very few studies have focused on their concentration in waste cooking oil (WCO) and oil deodorizer distillate (ODD). Objective: This study aimed (1) to design a reliable method to determine 16 PAHs and 4 OPAHs in both WCO and ODD and (2) to determine and analyze PAH and OPAH concentrations in actual samples to provide references for further research. Method: The PAH determination approach included double liquid–liquid extraction, double solid-phase extraction, and GC–triple quadrupole tandem MS determination. Oxidation indices were determined by titrimetry. Results: The method reached good linearity (R2 > 0.99) and an acceptable recovery rate (55.01–126.16% for WCO and 57.48–128.97% for ODD). Ten WCO and five ODD samples were determined, and the total concentration of 16 PAHs varied from 16.34 to 239.01 and 101.08 to 198.04 μg/kg in WCO and ODD, respectively. Among the 16 PAHs, three-ring PAHs typically contributed the most. It was also found that the acid value has a strong correlation with the concentration of OPAHs, probably because of the contribution of free fatty acids to OPAH formation. Conclusions: The proposed method was effective in the analysis of PAHs and OPAHs in WCO and ODD.

Los estilos APA, Harvard, Vancouver, ISO, etc.

4

Sonego, Elisa, Bina Bhattarai y Lene Duedahl-Olesen. "Detection of Nitrated, Oxygenated and Hydrogenated Polycyclic Aromatic Compounds in Smoked Fish and Meat Products". Foods 11, n.º 16 (13 de agosto de 2022): 2446. http://dx.doi.org/10.3390/foods11162446.

Texto completo

Resumen

Polycyclic aromatic hydrocarbons (PAHs) are present in smoked food products. More toxic nitrated (NPAH) and oxygenated (OPAH) PAHs derivatives are found concomitantly to PAHs and are therefore believed to be found in smoked food products. However, only a few PAH analyses on food include these derivatives. We adjusted and successfully validated a GC-QTOFMS method including 13 NPAHs and 2 OPAHs as well as the 4 regulated PAHs for analysis of 14 smoked (13 fish and one bacon) and one pan fried fish samples.OPAHs were detected in the highest concentrations in 13 of 15 samples. Non-target screening revealed the presence of an additional four OPAHs and two methylated PAHs. Future food analysis should, based on these results, focus on PAH and oxygenated derivatives.

Los estilos APA, Harvard, Vancouver, ISO, etc.

5

Ringuet, J., E. Leoz-Garziandia, H. Budzinski, E. Villenave y A. Albinet. "Particle size distribution of nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) on traffic and suburban sites of a European megacity: Paris (France)". Atmospheric Chemistry and Physics Discussions 12, n.º 6 (6 de junio de 2012): 14169–96. http://dx.doi.org/10.5194/acpd-12-14169-2012.

Texto completo

Resumen

Abstract. The size distribution of particulate nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) was determined during two field campaigns at a traffic site in summer 2010 and at a suburban site during the MEGAPOLI (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation) experiment in summer 2009. Both, OPAHs and NPAHs were strongly associated (>85%) to fines particles (Dp < 2.5 μm) increasing the interest of their study on a sanitary point of view. Results showed really different NPAH and OPAH particle size distributions between both sites. At traffic site, clearly bimodal (notably for NPAHs) particle size distributions (Dp = 0.14 and 1.4 μm) were observed, while the particle size distributions were more scattered at the suburban site, especially for OPAHs. Bimodal particle size distribution observed at traffic site for the NPAH could be assigned to the vehicle emissions and the particle resuspension. Broadest distribution observed at the suburban site could be attributed to the mass transfer of compounds by volatilization/sorption processes during the transport of particles in the atmosphere. Results also showed that the combination of the study of particle size distributions applied to marker compounds (primary: 1-nitropyrene; secondary: 2-nitrofluoranthene) and to NPAH or OPAH chemical profiles bring some indications on their primary and/or secondary origin. Indeed, 1,4-anthraquinone seemed only primary emitted by vehicles while 7-nitrobenz[a]anthracene, benz[a]antracen7,12-dione and benzo[b]fluorenone seemed secondarily formed in the atmosphere.

Los estilos APA, Harvard, Vancouver, ISO, etc.

6

Ringuet, J., E. Leoz-Garziandia, H. Budzinski, E. Villenave y A. Albinet. "Particle size distribution of nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) on traffic and suburban sites of a European megacity: Paris (France)". Atmospheric Chemistry and Physics 12, n.º 18 (28 de septiembre de 2012): 8877–87. http://dx.doi.org/10.5194/acp-12-8877-2012.

Texto completo

Resumen

Abstract. The size distribution of particulate nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) was determined during two field campaigns at a traffic site in summer 2010 and at a suburban site during the MEGAPOLI (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation) experiment in summer 2009. Both, OPAHs and NPAHs were strongly associated (>85%) to fine particles (Dp< 2.5 μm) increasing the interest of their study on a sanitary point of view. Results showed really different NPAH and OPAH particle size distributions between both sites. At traffic site, clearly bimodal (notably for NPAHs) particle size distributions (Dp = 0.14 and 1.4 μm) were observed, while the particle size distributions were more scattered at the suburban site, especially for OPAHs. Bimodal particle size distribution observed at traffic site for the NPAH could be assigned to the vehicle emissions and the particle resuspension. Broadest distribution observed at the suburban site could be attributed to the mass transfer of compounds by volatilization/sorption processes during the transport of particles in the atmosphere. Results also showed that the combination of the study of particle size distributions applied to marker compounds (primary: 1-nitropyrene; secondary: 2-nitrofluoranthene) and to NPAH or OPAH chemical profiles bring some indications on their primary and/or secondary origin. Indeed, 1,4-anthraquinone seemed only primary emitted by vehicles while 7-nitrobenz[a]anthracene, benz[a]antracen7,12-dione and benzo[b]fluorenone seemed secondarily formed in the atmosphere.

Los estilos APA, Harvard, Vancouver, ISO, etc.

7

Kukuev, E. I. "Juvenile Individuals of Opahs (Lampridae) from the Atlantic and Pacific Oceans. Notes on the Systematics and Distribution of Opahs, Including the Description of a New Subgenus, Paralampris subgen. nov." Journal of Ichthyology 61, n.º 2 (marzo de 2021): 182–89. http://dx.doi.org/10.1134/s0032945221020089.

Texto completo

Resumen

Abstract Juvenile specimens of opahs (Lampridae) from the Southwest Atlantic, southeastern Pacific Ocean, and Gulf of Guinea are described. A taxonomic review of the composition of the family Lampridae is carried out, taking into account the recent revision of opah species of the genus Lampris and our own data. A new subgenus, Paralampris subgen. nov., has been identified.

Los estilos APA, Harvard, Vancouver, ISO, etc.

8

Elzein, Atallah, Rachel E. Dunmore, Martyn W. Ward, Jacqueline F. Hamilton y Alastair C. Lewis. "Variability of polycyclic aromatic hydrocarbons and their oxidative derivatives in wintertime Beijing, China". Atmospheric Chemistry and Physics 19, n.º 13 (10 de julio de 2019): 8741–58. http://dx.doi.org/10.5194/acp-19-8741-2019.

Texto completo

Resumen

Abstract. Ambient particulate matter (PM) can contain a mix of different toxic species derived from a wide variety of sources. This study quantifies the diurnal variation and nocturnal abundance of 16 polycyclic aromatic hydrocarbons (PAHs), 10 oxygenated PAHs (OPAHs) and 9 nitrated PAHs (NPAHs) in ambient PM in central Beijing during winter. Target compounds were identified and quantified using gas chromatography–time-of-flight mass spectrometry (GC-Q-ToF-MS). The total concentration of PAHs varied between 18 and 297 ng m−3 over 3 h daytime filter samples and from 23 to 165 ng m−3 in 15 h night-time samples. The total concentrations of PAHs over 24 h varied between 37 and 180 ng m−3 (mean: 97±43 ng m−3). The total daytime concentrations during high particulate loading conditions for PAHs, OPAHs and NPAHs were 224, 54 and 2.3 ng m−3, respectively. The most abundant PAHs were fluoranthene (33 ng m−3), chrysene (27 ng m−3), pyrene (27 ng m−3), benzo[a]pyrene (27 ng m−3), benzo[b]fluoranthene (25 ng m−3), benzo[a]anthracene (20 ng m−3) and phenanthrene (18 ng m−3). The most abundant OPAHs were 9,10-anthraquinone (18 ng m−3), 1,8-naphthalic anhydride (14 ng m−3) and 9-fluorenone (12 ng m−3), and the three most abundant NPAHs were 9-nitroanthracene (0.84 ng m−3), 3-nitrofluoranthene (0.78 ng m−3) and 3-nitrodibenzofuran (0.45 ng m−3). ∑PAHs and ∑OPAHs showed a strong positive correlation with the gas-phase abundance of NO, CO, SO2 and HONO, indicating that PAHs and OPAHs can be associated with both local and regional emissions. Diagnostic ratios suggested emissions from traffic road and coal combustion were the predominant sources of PAHs in Beijing and also revealed the main source of NPAHs to be secondary photochemical formation rather than primary emissions. PM2.5 and NPAHs showed a strong correlation with gas-phase HONO. 9-Nitroanthracene appeared to undergo a photodegradation during the daytime and showed a strong positive correlation with ambient HONO (R=0.90, P < 0.001). The lifetime excess lung cancer risk for those species that have available toxicological data (16 PAHs, 1 OPAH and 6 NPAHs) was calculated to be in the range 10−5 to 10−3 (risk per million people ranges from 26 to 2053 cases per year).

Los estilos APA, Harvard, Vancouver, ISO, etc.

9

Shahpoury, Pourya, Zoran Kitanovski y Gerhard Lammel. "Snow scavenging and phase partitioning of nitrated and oxygenated aromatic hydrocarbons in polluted and remote environments in central Europe and the European Arctic". Atmospheric Chemistry and Physics 18, n.º 18 (24 de septiembre de 2018): 13495–510. http://dx.doi.org/10.5194/acp-18-13495-2018.

Texto completo

Resumen

Abstract. Nitrated and oxygenated polycyclic aromatic hydrocarbons (N/OPAHs) are emitted in combustion processes and formed in polluted air. Their environmental cycling through wet deposition has hardly been studied. Fresh snow samples at urban and rural sites in central Europe, as well as surface snow from a remote site in Svalbard, were analysed for 17 NPAHs, 8 OPAHs, and 11 nitrated mono-aromatic hydrocarbons (NMAHs), of which most N/OPAHs as well as nitrocatechols, nitrosalicylic acids, and 4-nitroguaiacol are studied for the first time in precipitation. In order to better understand the scavenging mechanisms, the particulate mass fractions (θ) at 273 K were predicted using a multi-phase gas-particle partitioning model based on polyparameter linear free energy relationships. ∑NPAH concentrations were 1.2–17.6 and 8.8–19.1 ng L−1 at urban and rural sites, whereas ∑OPAHs were 79.8–955.2 and 343.3–1757.4 ng L−1 at these sites, respectively. 9,10-anthraquinone was predominant in snow aqueous and particulate phases. NPAHs were only found in the particulate phase with 9-nitroanthracene being predominant followed by 2-nitrofluoranthene. Among NMAHs, 4-nitrophenol showed the highest abundance in both phases. The levels found for nitrophenols were in the same range or lower than those reported in the 1980s and 1990s. The lowest levels of ∑N/OPAHs and ∑NMAHs were found at the remote site (3.5 and 390.5 ng L−1, respectively). N/OPAHs preferentially partitioned in snow particulate phase in accordance with predicted θ, whereas NMAHs were predominant in the aqueous phase, regardless of θ. It is concluded that the phase distribution of non-polar N/OPAHs in snow is determined by their gas-particle partitioning prior to snow scavenging, whereas that for polar particulate phase substances, i.e. NMAHs, is determined by an interplay between gas-particle partitioning in the aerosol and dissolution during in- or below-cloud scavenging.

Los estilos APA, Harvard, Vancouver, ISO, etc.

10

Niu, Yue, Ling Zhou, Huiqi Wang, Jiayu Dai, Ying Bao, Baohong Hou y Qiuxiang Yin. "Enhancing the Water Solubility of 9-Fluorenone Using Cyclodextrin Inclusions: A Green Approach for the Environmental Remediation of OPAHs". Crystals 13, n.º 5 (6 de mayo de 2023): 775. http://dx.doi.org/10.3390/cryst13050775.

Texto completo

Resumen

Oxygenated polycyclic aromatic hydrocarbons (OPAHs) are toxic and carcinogenic compounds widely present in the natural environment, posing a serious threat to the environment and human health. However, the removal of OPAHs is mainly hindered by their low water solubility. Cyclodextrins (CDs) are frequently used to form inclusion complexes (ICs) with hydrophobic molecules to improve their solubility. In this study, we investigated the solubility enhancement ability of different CDs on 9-fluorenone, a common OPAH, through phase solubility experiments. We successfully prepared three solid ICs of 9-fluorenone with β-, hydroxypropyl-β-(HP-β-) and sulfobutylether-β-CD (SBE-β-CD) using the cooling crystallization method for the first time and characterized them via powder X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, etc. Molecular dynamics simulations were employed to investigate the binding modes and stable configurations of the ICs in the liquid phase and to explore the factors affecting their solubility enhancement ability. The results showed that all the CDs had a solubility enhancement effect on 9-fluorenone, with SBE-β-CD displaying the strongest effect, increasing the solubility of 9-fluorenone by 146 times. HP-β-CD, β-CD, α-CD, and γ-CD followed in decreasing order. Moreover, 9-fluorenone formed a ratio of 1:1 ICs to CDs. In addition, the interaction energy between SBE-β-CD and 9-fluorenone was the lowest among the CDs, which further validated the results of the phase solubility experiments from a theoretical perspective. Overall, this study provides a green method for the removal of 9-fluorenone pollutants in the environment and is expected to be applied to the removal and environmental remediation of other OPAHs.

Los estilos APA, Harvard, Vancouver, ISO, etc.

11

Jia, Yaning, Weixia Li, Yanlin Li, Lei Zhao, Chenguang Li, Lei Wang, Junkai Fang et al. "The Levels of Polycyclic Aromatic Hydrocarbons and Their Derivatives in Plasma and Their Effect on Mitochondrial DNA Methylation in the Oilfield Workers". Toxics 11, n.º 5 (17 de mayo de 2023): 466. http://dx.doi.org/10.3390/toxics11050466.

Texto completo

Resumen

This study focuses on the components and levels of polycyclic aromatic hydrocarbons (PAHs) and their derivatives (MPAHs and OPAHs) in plasma samples from 19 oil workers, pre- and post-workshift, and their exposure–response relationship with mitochondrial DNA (mtDNA) methylation. PAH, MPAH, OPAH, and platelet mtDNA methylation levels were determined using a gas chromatograph mass spectrometer (GC-MS) and a pyrosequencing protocol, respectively. The total plasma concentrations of PAHs in mean value were, respectively, 31.4 ng/mL and 48.6 ng/mL in pre- and post-workshift, and Phe was the most abundant (13.3 ng/mL in pre-workshift and 22.1 ng/mL in post-workshift, mean value). The mean values of total concentrations of MPAHs and OPAHs in the pre-workshift were 2.7 ng/mL and 7.2 ng/mL, while in the post-workshift, they were 4.5 ng/mL and 8.7 ng/mL, respectively. The differences in the mean MT-COX1, MT-COX2, and MT-COX3 methylation levels between pre- and post-workshift were 2.36%, 5.34%, and 0.56%. Significant (p < 0.05) exposure–response relationships were found between PAHs and mtDNA methylation in the plasma of workers; exposure to Anthracene (Ant) could induce the up-regulation of the methylation of MT-COX1 (β = 0.831, SD = 0.105, p < 0.05), and exposure to Fluorene (Flo) and Phenanthrene (Phe) could induce the up-regulation of methylation of MT-COX3 (β = 0.115, SD = 0.042, p < 0.05 and β = 0.036, SD = 0.015, p < 0.05, respectively). The results indicated that exposure to PAHs was an independent factor influencing mtDNA methylation.

Los estilos APA, Harvard, Vancouver, ISO, etc.

12

Wietzoreck, Marco, Marios Kyprianou, Benjamin A. Musa Bandowe, Siddika Celik, John N. Crowley, Frank Drewnick, Philipp Eger et al. "Polycyclic aromatic hydrocarbons (PAHs) and their alkylated, nitrated and oxygenated derivatives in the atmosphere over the Mediterranean and Middle East seas". Atmospheric Chemistry and Physics 22, n.º 13 (7 de julio de 2022): 8739–66. http://dx.doi.org/10.5194/acp-22-8739-2022.

Texto completo

Resumen

Abstract. Polycyclic aromatic hydrocarbons (PAHs) and their alkylated (RPAHs), nitrated (NPAHs) and oxygenated (OPAHs) derivatives are air pollutants. Many of these substances are long-lived, can undergo long-range atmospheric transport and adversely affect human health upon exposure. However, the occurrence and fate of these air pollutants have hardly been studied in the marine atmosphere. In this study, we report the atmospheric concentrations over the Mediterranean Sea, the Red Sea, the Arabian Sea, the Gulf of Oman and the Arabian Gulf, determined during the AQABA (Air Quality and Climate Change in the Arabian Basin) project, a comprehensive ship-borne campaign in summer 2017. The average concentrations of ∑26PAHs, ∑19RPAHs, ∑11OPAHs and ∑17NPAHs, in the gas and particulate phases, were 2.99 ± 3.35 ng m−3, 0.83 ± 0.87 ng m−3, 0.24 ± 0.25 ng m−3 and 4.34 ± 7.37 pg m−3, respectively. The Arabian Sea region was the cleanest for all substance classes, with concentrations among the lowest ever reported. Over the Mediterranean Sea, we found the highest average burden of ∑26PAHs and ∑11OPAHs, while the ∑17NPAHs were most abundant over the Arabian Gulf (known also as the Persian Gulf). 1,4-Naphthoquinone (1,4-O2NAP) followed by 9-fluorenone and 9,10-anthraquinone were the most abundant studied OPAHs in most samples. The NPAH composition pattern varied significantly across the regions, with 2-nitronaphthalene (2-NNAP) being the most abundant NPAH. According to source apportionment investigations, the main sources of PAH derivatives in the region were ship exhaust emissions, residual oil combustion and continental pollution. All OPAHs and NPAHs except 2-nitrofluoranthene (2-NFLT), which were frequently detected during the campaign, showed elevated concentrations in fresh shipping emissions. In contrast, 2-NFLT and 2-nitropyrene (2-NPYR) were highly abundant in aged shipping emissions due to secondary formation. Apart from 2-NFLT and 2-NPYR, benz(a)anthracene-7,12-dione and 2-NNAP also had significant photochemical sources. Another finding was that the highest concentrations of PAHs, OPAHs and NPAHs were found in the sub-micrometre fraction of particulate matter (PM1).

Los estilos APA, Harvard, Vancouver, ISO, etc.

13

Kitanovski, Zoran, Pourya Shahpoury, Constantini Samara, Aristeidis Voliotis y Gerhard Lammel. "Composition and mass size distribution of nitrated and oxygenated aromatic compounds in ambient particulate matter from southern and central Europe – implications for the origin". Atmospheric Chemistry and Physics 20, n.º 4 (2 de marzo de 2020): 2471–87. http://dx.doi.org/10.5194/acp-20-2471-2020.

Texto completo

Resumen

Abstract. Nitro-monoaromatic hydrocarbons (NMAHs), such as nitrocatechols, nitrophenols and nitrosalicylic acids, are important constituents of atmospheric particulate matter (PM) water-soluble organic carbon (WSOC) and humic-like substances (HULIS). Nitrated and oxygenated derivatives of polycyclic aromatic hydrocarbons (NPAHs and OPAHs) are toxic and ubiquitous in the ambient air; due to their light absorption properties, together with NMAHs, they are part of aerosol brown carbon (BrC). We investigated the winter concentrations of these substance classes in size-resolved PM from two urban sites in central and southern Europe, i.e. Mainz (MZ), Germany, and Thessaloniki (TK), Greece. The total concentration of 11 NMAHs (∑11NMAH concentrations) measured in PM10 and total PM were 0.51–8.38 and 12.1–72.1 ng m−3 at the MZ and TK sites, respectively, whereas ∑7OPAHs were 47–1636 and 858–4306 pg m−3, and ∑8NPAHs were ≤90 and 76–578 pg m−3, respectively. NMAHs contributed 0.4 % and 1.8 % to the HULIS mass at MZ and TK, respectively. The mass size distributions of the individual substances generally peaked in the smallest or second smallest size fraction i.e. <0.49 or 0.49–0.95 µm. The mass median diameter (MMD) of NMAHs was 0.10 and 0.27 µm at MZ and TK, respectively, while the MMDs of NPAHs and OPAHs were both 0.06 µm at MZ and 0.12 and 0.10 µm at TK. Correlation analysis between NMAHs, NPAHs, and OPAHs from one side and WSOC, HULIS, sulfate, and potassium from the other suggested that fresh biomass burning (BB) and fossil fuel combustion emissions dominated at the TK site, while aged air masses were predominant at the MZ site.

Los estilos APA, Harvard, Vancouver, ISO, etc.

14

Lim, Hwanmi, Sanna Silvergren, Silvia Spinicci, Farshid Mashayekhy Rad, Ulrika Nilsson, Roger Westerholm y Christer Johansson. "Contribution of wood burning to exposures of PAHs and oxy-PAHs in Eastern Sweden". Atmospheric Chemistry and Physics 22, n.º 17 (5 de septiembre de 2022): 11359–79. http://dx.doi.org/10.5194/acp-22-11359-2022.

Texto completo

Resumen

Abstract. A growing trend in developed countries is the use of wood as fuel for domestic heating due to measures taken to reduce the usage of fossil fuels. However, this imposed another issue with the environment and human health. That is, the emission from wood burning contributed to the increased level of atmospheric particulates and the wood smoke caused various respiratory diseases. The aim of this study was to investigate the impact of wood burning on the polycyclic aromatic hydrocarbons (PAHs) in air PM10 using known wood burning tracers, i.e. levoglucosan, mannosan and galactosan from the measurement at the urban background and residential areas in Sweden. A yearly measurement from three residential areas in Sweden showed a clear seasonal variation of PAHs during the cold season mainly from increased domestic heating and meteorology. Together, an increased sugar level assured the wood burning during the same period. The sugar ratio (levoglucosan/(mannosan+galactosan)) was a good marker for wood burning source such as the wood type used for domestic heating and garden waste burning. On the Walpurgis Night, the urban background measurement demonstrated a dramatic increase in levoglucosan, benzo[a]pyrene (B[a]P) and oxygenated PAHs (OPAHs) concentrations from the increased wood burning. A significant correlation between levoglucosan and OPAHs was observed suggesting OPAHs to be an indicator of wood burning together with levoglucosan. The levoglucosan tracer method and modelling used in predicting the B[a]P concentration could not fully explain the measured levels in the cold season. The model showed that the local wood source contributed to 98 % of B[a]P emissions in the Stockholm area and 2 % from the local traffic. However, non-local sources were dominating in the urban background (60 %). A further risk assessment estimated that the airborne particulate PAHs caused 13.4 cancer cases per 0.1 million inhabitants in Stockholm County.

Los estilos APA, Harvard, Vancouver, ISO, etc.

15

Cao, Wei, Jing Yuan, Shuying Geng, Jing Zou, Junfeng Dou y Fuqiang Fan. "Oxygenated and Nitrated Polycyclic Aromatic Hydrocarbons: Sources, Quantification, Incidence, Toxicity, and Fate in Soil—A Review Study". Processes 11, n.º 1 (26 de diciembre de 2022): 52. http://dx.doi.org/10.3390/pr11010052.

Texto completo

Resumen

The genotoxicity, mutagenesis, and carcinogenic effects of polycyclic aromatic hydrocarbon (PAH) derivatives may exceed the parent PAHs. However, their influence on the soil environment has not been explored to a large extent. Oxygenated polycyclic aromatic hydrocarbons (OPAHs) and nitrated polycyclic aromatic hydrocarbons (NPAHs) are typical polar substituted compounds. We offer a review of the literature on the sources, quantification, incidence, toxicity, and transport of these compounds in soil. Although their environmental concentrations are lower than those of their parent compounds, they exert higher toxicity. Both types of substances are basically related to carcinogenesis. OPAHs are not enzymatically activated and can generate reactive oxygen species in biological cells, while NPAHs have been shown to be mutagenic, genotoxic, and cytotoxic. These compounds are largely derived from the transformation of PAHs, but they behave differently in soil because of their higher molecular weight and dissimilar adsorption mechanisms. Therefore, specialized knowledge of model derivatives is required. We also made recommendations for future directions based on existing research. It is expected that the review will trigger scientific discussions and provide a research basis for further study on PAH derivatives in the soil environment.

Los estilos APA, Harvard, Vancouver, ISO, etc.

16

Hayakawa, Kazuichi. "Recent Research Progress on Nitropolycyclic Aromatic Hydrocarbons in Outdoor and Indoor Environments". Applied Sciences 12, n.º 21 (6 de noviembre de 2022): 11259. http://dx.doi.org/10.3390/app122111259.

Texto completo

Resumen

Nitropolycyclic aromatic hydrocarbons (NPAHs) are derivatives of PAHs and contain one or more nitro functional groups (-NO2). Some NPAHs are classified as possible or probable human carcinogens and are more mutagenic than PAHs. Although the atmospheric cancer risk is estimated as 11% from PAHs but 17% from NPAHs, many of the atmospheric behaviors of NPAHs are unknown. There are two major NPAH formation processes. Primary formation of NPAHs occurs directly during the combustion of organic materials. The secondary formation of NPAHs occurs through the transformation of PAHs after they have been released into the environment. The fate, transport, and health effects of NPAHs are considerably different from their parent PAHs because of these differing formation processes. However, the amount of research conducted on NPAHs is comparatively low relative to PAHs. This is primarily due to a lack of effective analytical method for NPAHs, which generally exist in the environment at concentrations one to three orders of magnitude lower than PAHs. However, with the development of more sensitive analytical methods, the number of research papers published on NPAHs has recently increased. The Western Pacific region, one of the post polluted areas in the world, is the most frequently studied area for NPAHs. Many of them reported that atmospheric concentrations of NPAHs were much lower than parent PAHs and oxygenated derivatives (OPAHs). In this article, recent research on sample treatment and analysis, as well as the sources and environmental fate of NPAHs, are discussed with PAHs and OPAHs. A notable achievement using NPAHs is the development of a new emission source analysis method, the NP method, whose features are also discussed in this review.

Los estilos APA, Harvard, Vancouver, ISO, etc.

17

Tidwell, Lane G., L. Blair Paulik y Kim A. Anderson. "Air-water exchange of PAHs and OPAHs at a superfund mega-site". Science of The Total Environment 603-604 (diciembre de 2017): 676–86. http://dx.doi.org/10.1016/j.scitotenv.2017.01.185.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

18

Huang, Wei, Bo Huang, Xinhui Bi, Qinhao Lin, Ming Liu, Zhaofang Ren, Guohua Zhang, Xinming Wang, Guoying Sheng y Jiamo Fu. "Emission of PAHs, NPAHs and OPAHs from residential honeycomb coal briquette combustion". Energy & Fuels 28, n.º 1 (7 de enero de 2014): 636–42. http://dx.doi.org/10.1021/ef401901d.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

19

Kukuev, E. I. "Erratum to: Juvenile Individuals of Opahs (Lampridae) from the Atlantic and Pacific Oceans. Notes on the Systematics and Distribution of Opahs, Including the Description of a New Subgenus, Paralampris subgen. nov." Journal of Ichthyology 61, n.º 4 (julio de 2021): 654. http://dx.doi.org/10.1134/s0032945221440016.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

20

Jariyasopit, Narumol, Yifeng Zhang, Jonathan W. Martin y Tom Harner. "Comparison of polycyclic aromatic compounds in air measured by conventional passive air samplers and passive dry deposition samplers and contributions from petcoke and oil sands ore". Atmospheric Chemistry and Physics 18, n.º 12 (29 de junio de 2018): 9161–71. http://dx.doi.org/10.5194/acp-18-9161-2018.

Texto completo

Resumen

Abstract. Conventional passive air samplers (PAS) and passive dry deposition samplers (PAS-DD) were deployed along a 90 km south–north transect at five sites in the Athabasca oil sands region (AOSR) during October to November 2015. The purpose was to compare and characterize the performance of the two passive sampling methods for targeted compounds across a range of site types. Samples were analyzed for polycyclic aromatic compounds (PACs), nitrated polycyclic aromatic hydrocarbons (NPAHs), and oxygenated PAHs (OPAHs). ΣPAC and ΣNPAH concentrations were highest in PAS and PAS-DD samplers at site AMS5, which is the closest sampling site to surface mining and upgrading facilities. The OPAHs were elevated at site AMS6, which is located in the town of Fort McMurray, approximately 30 km south of the main mining area. PAS-DD was enriched relative to PAS in particle-associated target chemicals, which is consistent with the relatively more open design of PAS-DD intended to capture particle-phase (and gas-phase) deposition. Petroleum coke (petcoke) (i.e., the carbonaceous byproduct of bitumen upgrading) and oil sands ore (i.e., the material mined in open-pit mines from which bitumen is extracted) were assessed for their potential to be a source of PACs to air in the oil sands region. The ore samples contained ∼ 8 times and ∼ 40 times higher ΣPACs concentrations (dry weight basis) than delayed and fluid petcoke, respectively. The residue analysis of ore and petcoke samples also revealed that the chemical 4-nitrobiphenyl (4-NBP) can be used to track gas-phase emissions to air. A comparison of chemical residues in ore, petcoke, and air samples revealed that the ore is likely a major contributor to volatile PACs present in air and that both ore and petcoke are contributing to the particle-associated PACs in air near open-pit mining areas. The contribution of petcoke particles in passive air samples was also confirmed qualitatively using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS).

Los estilos APA, Harvard, Vancouver, ISO, etc.

21

Zhang, Bin, Zezhi Peng, Jing Lv, Qin Peng, Kun He, Hongmei Xu, Jian Sun y Zhenxing Shen. "Gas Particle Partitioning of PAHs Emissions from Typical Solid Fuel Combustions as Well as Their Health Risk Assessment in Rural Guanzhong Plain, China". Toxics 11, n.º 1 (15 de enero de 2023): 80. http://dx.doi.org/10.3390/toxics11010080.

Texto completo

Resumen

Air pollutants from the incomplete combustion of rural solid fuels are seriously harmful to both air quality and human health. To quantify the health effects of different fuel–stove combinations, gas and particle partitioning of twenty-nine species of polycyclic aromatic hydrocarbons (PAHs) emitted from seven fuel–stove combinations were examined in this study, and the benzo (a) pyrene toxicity equivalent (BaPeq) and cancer risks were estimated accordingly. The results showed that the gas phase PAHs (accounting for 68–78% of the total PAHs) had higher emission factors (EFs) than particulate ones. For all combustion combinations, pPAHs accounted for the highest proportion (84.5% to 99.3%) in both the gas and particulate phases, followed by aPAHs (0.63–14.7%), while the proportions of nPAHs and oPAHs were much lower (2–4 orders of magnitude) than pPAHs. For BaPeq, particulate phase PAHs dominated the BaPeq rather than gas ones, which may be due to the greater abundance of 5-ring particle PAHs. Gas and particle pPAHs were both predominant in the BaPeq, with proportions of 95.2–98.6% for all combustion combinations. Cancer risk results showed a descending order of bituminous coal combustion (0.003–0.05), biomass burning (0.002–0.01), and clean briquette coal combustion (10−5–0.001), indicating that local residents caused a severe health threat by solid fuel combustion (the threshold: 10−4). The results also highlighted that clean briquette coal could reduce cancer risks by 1–2 orders of magnitude compared to bulk coal and biomass. For oPAH, BcdPQ (6H-benzo(c,d)pyrene-6-one) had the highest cancer risk, ranging from 4.83 × 10−5 to 2.45 × 10−4, which were even higher than the total of aPAHs and nPAHs. The dramatically high toxicity and cancer risk of PAHs from solid fuel combustion strengthened the necessity and urgency of clean heating innovation in Guanzhong Plain and in similar places.

Los estilos APA, Harvard, Vancouver, ISO, etc.

22

O’Connell, Steven G., Theodore Haigh, Glenn Wilson y Kim A. Anderson. "An analytical investigation of 24 oxygenated-PAHs (OPAHs) using liquid and gas chromatography–mass spectrometry". Analytical and Bioanalytical Chemistry 405, n.º 27 (5 de septiembre de 2013): 8885–96. http://dx.doi.org/10.1007/s00216-013-7319-x.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

23

Xiao, Lingfeng, Song Hu, Hengda Han, Qiangqiang Ren, Limo He, Long Jiang, Sheng Su, Yi Wang y Jun Xiang. "An insight into the OPAHs and SPAHs formation mechanisms during alkaline lignin pyrolysis at different temperatures". Journal of Analytical and Applied Pyrolysis 156 (junio de 2021): 105104. http://dx.doi.org/10.1016/j.jaap.2021.105104.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

24

Wang, Wentao, Narumol Jariyasopit, Jill Schrlau, Yuling Jia, Shu Tao, Tian-Wei Yu, Roderick H. Dashwood, Wei Zhang, Xuejun Wang y Staci L. Massey Simonich. "Concentration and Photochemistry of PAHs, NPAHs, and OPAHs and Toxicity of PM2.5during the Beijing Olympic Games". Environmental Science & Technology 45, n.º 16 (15 de agosto de 2011): 6887–95. http://dx.doi.org/10.1021/es201443z.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

25

Chen, Weisong, Weixuan Xian, Guiying He, Zhongye Xue, Shaomin Li, Wenyan Li, Yongtao Li, Yulong Zhang y Xingjian Yang. "Occurrence and spatiotemporal distribution of PAHs and OPAHs in urban agricultural soils from Guangzhou City, China". Ecotoxicology and Environmental Safety 254 (abril de 2023): 114767. http://dx.doi.org/10.1016/j.ecoenv.2023.114767.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

26

Wilcke, Wolfgang, Mario Kiesewetter y Benjamin A. Musa Bandowe. "Microbial formation and degradation of oxygen-containing polycyclic aromatic hydrocarbons (OPAHs) in soil during short-term incubation". Environmental Pollution 184 (enero de 2014): 385–90. http://dx.doi.org/10.1016/j.envpol.2013.09.020.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

27

Kayanuma, Megumi, Shunsuke Suzuki, Yoong-Kee Choe y Yukihiro Shimoi. "Structure dependency of the reactivity of aromatic hydrocarbons involving the formation of oxygenated polycyclic aromatic hydrocarbons (OPAHs)". Chemical Physics Letters 754 (septiembre de 2020): 137652. http://dx.doi.org/10.1016/j.cplett.2020.137652.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

28

Xiao, Lingfeng, Song Hu, Long Jiang, Sheng Su, Yi Wang y Jun Xiang. "The OPAHs from hemicellulose pyrolysis tar at different temperature characterization via GC-MS and ESI FT-ICR MS". IOP Conference Series: Earth and Environmental Science 657 (20 de febrero de 2021): 012028. http://dx.doi.org/10.1088/1755-1315/657/1/012028.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

29

Ringuet, Johany, Alexandre Albinet, Eva Leoz-Garziandia, Hélène Budzinski y Eric Villenave. "Reactivity of polycyclic aromatic compounds (PAHs, NPAHs and OPAHs) adsorbed on natural aerosol particles exposed to atmospheric oxidants". Atmospheric Environment 61 (diciembre de 2012): 15–22. http://dx.doi.org/10.1016/j.atmosenv.2012.07.025.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

30

Musa Bandowe, Benjamin A., Nosir Shukurov, Michael Kersten y Wolfgang Wilcke. "Polycyclic aromatic hydrocarbons (PAHs) and their oxygen-containing derivatives (OPAHs) in soils from the Angren industrial area, Uzbekistan". Environmental Pollution 158, n.º 9 (septiembre de 2010): 2888–99. http://dx.doi.org/10.1016/j.envpol.2010.06.012.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

31

Lan, Jianqiang y Shimin Wu. "Occurrence, Concentration and Toxicity of 54 Polycyclic Aromatic Hydrocarbons in Butter during Storage". Foods 12, n.º 24 (6 de diciembre de 2023): 4393. http://dx.doi.org/10.3390/foods12244393.

Texto completo

Resumen

Polycyclic aromatic hydrocarbons (PAHs) are a class of highly carcinogenic compounds with a lipophilic nature. This study investigated the characterization of PAH24 contamination in twenty-one types of butter and five types of margarines using the QuEChERS pretreatment coupled with GC-QqQ-MS. Additionally, low-temperature storage experiments were conducted to explore the variations in oxidation index as well as the PAH levels. The results revealed that PAH24 concentrations in butter and margarine were 50.75–310.64 μg/kg and 47.66–118.62 μg/kg, respectively. The PAH4 level in one type of butter reached 11.24 μg/kg beyond the EU standards. Over 160 days of storage at 4 °C, acid value (AV), peroxide value (POV), and acidity significantly increased, while malondialdehyde (MDA) content and carbonyl value (CGV) fluctuated. Concentrations of PAH24 and oxidized PAHs (OPAHs) experienced a notable reduction of 29.09% and 63.85%, respectively. The slow reduction in naphthalene (NaP) indicated the dynamic nature of PAHs during storage. However, the toxic equivalency quotients (TEQs) decreased slightly from a range of 0.65–1.90 to 0.39–1.77, with no significant difference. This study contributes to the understanding of variations in PAHs during storage, which is of great significance for food safety.

Los estilos APA, Harvard, Vancouver, ISO, etc.

32

Musa Bandowe, Benjamin A., Jaroslava Sobocka y Wolfgang Wilcke. "Oxygen-containing polycyclic aromatic hydrocarbons (OPAHs) in urban soils of Bratislava, Slovakia: Patterns, relation to PAHs and vertical distribution". Environmental Pollution 159, n.º 2 (febrero de 2011): 539–49. http://dx.doi.org/10.1016/j.envpol.2010.10.011.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

33

Zhang, Junmei, Lingxiao Yang, Abdelwahid Mellouki, Jianmin Chen, Xiangfeng Chen, Ying Gao, Pan Jiang, Yanyan Li, Hao Yu y Wenxing Wang. "Diurnal concentrations, sources, and cancer risk assessments of PM2.5-bound PAHs, NPAHs, and OPAHs in urban, marine and mountain environments". Chemosphere 209 (octubre de 2018): 147–55. http://dx.doi.org/10.1016/j.chemosphere.2018.06.054.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

34

Zhang, Junmei, Lingxiao Yang, Abdelwahid Mellouki, Jianmin Chen, Xiangfeng Chen, Ying Gao, Pan Jiang, Yanyan Li, Hao Yu y Wenxing Wang. "Atmospheric PAHs, NPAHs, and OPAHs at an urban, mountainous, and marine sites in Northern China: Molecular composition, sources, and ageing". Atmospheric Environment 173 (enero de 2018): 256–64. http://dx.doi.org/10.1016/j.atmosenv.2017.11.002.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

35

Shin, Sun Min, Ji Yi Lee, Hye Jung Shin y Yong Pyo Kim. "Seasonal variation and source apportionment of Oxygenated Polycyclic Aromatic Hydrocarbons (OPAHs) and Polycyclic Aromatic Hydrocarbons (PAHs) in PM2.5 in Seoul, Korea". Atmospheric Environment 272 (marzo de 2022): 118937. http://dx.doi.org/10.1016/j.atmosenv.2022.118937.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

36

Huang, Bo, Ming Liu, Xinhui Bi, Chakra Chaemfa, Zhaofang Ren, Xinming Wang, Guoying Sheng y Jiamo Fu. "Phase distribution, sources and risk assessment of PAHs, NPAHs and OPAHs in a rural site of Pearl River Delta region, China". Atmospheric Pollution Research 5, n.º 2 (abril de 2014): 210–18. http://dx.doi.org/10.5094/apr.2014.026.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

37

Jiang, Pan, Lingxiao Yang, Xiangfeng Chen, Ying Gao, Yanyan Li, Junmei Zhang, Tong Zhao, Hao Yu y Wenxing Wang. "Impact of Dust Storms on NPAHs and OPAHs in PM2.5 in Jinan, China, in Spring 2016: Concentrations, Health Risks, and Sources". Aerosol and Air Quality Research 18, n.º 2 (2018): 471–84. http://dx.doi.org/10.4209/aaqr.2017.08.0274.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

38

Obrist, Daniel, Barbara Zielinska y Judith A. Perlinger. "Accumulation of polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs (OPAHs) in organic and mineral soil horizons from four U.S. remote forests". Chemosphere 134 (septiembre de 2015): 98–105. http://dx.doi.org/10.1016/j.chemosphere.2015.03.087.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

39

Zhang, Limin, Wei Li y Shimin Wu. "Rapid Determination of Oxygenated and Parent Polycyclic Aromatic Hydrocarbons in Milk Using Supercritical Fluid Chromatography-Mass Spectrometry". Foods 11, n.º 24 (8 de diciembre de 2022): 3980. http://dx.doi.org/10.3390/foods11243980.

Texto completo

Resumen

Liquid milks are consumed worldwide in large amounts, especially by adolescents and infants. Thus, their health quality linked with polycyclic aromatic hydrocarbon (PAH) contamination has attracted great concern. This study developed a rapid and sensitive supercritical fluid chromatography (SFC)-MS method to determine two typical oxygenated PAHs (OPAHs) and EU 15+1PAHs except for benzo[k]fluoranthene (BkF) in three types of liquid milks: 10 ultra heat treated (UHT) milks, 8 pasteurized milks, and 4 extended-shelf-life pasteurized milks. The instrumental analysis was 15 min with a recovery of 67.66–118.46%, a precision of 1.45–14.68%, detection limits of 0.04–0.24 μg/kg, and quantification limits of 0.13–0.78 μg/kg. We found 9-fluorenone, anthraquinone, 15 EU priority PAHs, and benzo[a]pyrene toxic equivalent quantity (BaPeq) in the 22 milk samples, which were 0.32–1.56 μg/kg, 0.40–1.74 μg/kg, 0.57–8.48 μg/kg, and 0.01–17.42 μg/kg, respectively. The UHT milks and whole fat milks showed higher PAH concentrations than other investigated samples, where the maximum levels of BaP and PAH4 were 0.77 and 3.61 μg/kg, respectively. PAH4 dominantly contributed to the PAH8 concentration and was detected in 73% and 32% of samples at more than 1.0 and 2.0 μg/kg, respectively. The results suggest that raw milks should be strictly monitored and extensively investigated for PAH4 and BaP concentrations for future risk assessment, limitations, and dietary guidance.

Los estilos APA, Harvard, Vancouver, ISO, etc.

40

Li, Yanyan, Lingxiao Yang, Xiangfeng Chen, Pan Jiang, Ying Gao, Junmei Zhang, Hao Yu y Wenxing Wang. "Indoor/outdoor relationships, sources and cancer risk assessment of NPAHs and OPAHs in PM2.5 at urban and suburban hotels in Jinan, China". Atmospheric Environment 182 (junio de 2018): 325–34. http://dx.doi.org/10.1016/j.atmosenv.2018.03.058.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

41

Degrendele, Céline, Tjaša Kanduč, David Kocman, Gerhard Lammel, Adriana Cambelová, Saul Garcia Dos Santos, Milena Horvat et al. "NPAHs and OPAHs in the atmosphere of two central European cities: Seasonality, urban-to-background gradients, cancer risks and gas-to-particle partitioning". Science of The Total Environment 793 (noviembre de 2021): 148528. http://dx.doi.org/10.1016/j.scitotenv.2021.148528.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

42

Arnoldsson, Kristina, Roger Magnusson, Lars Hägglund, Christian Lejon y Håkan Wingfors. "Initial evaluation of an axial passive sampler for PAHs and OPAHs using substrates with and without gas sampling capacity and varying diffusion distances". Atmospheric Pollution Research 6, n.º 4 (julio de 2015): 673–81. http://dx.doi.org/10.5094/apr.2015.076.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

43

Ringuet, Johany, Alexandre Albinet, Eva Leoz-Garziandia, Hélène Budzinski y Eric Villenave. "Diurnal/nocturnal concentrations and sources of particulate-bound PAHs, OPAHs and NPAHs at traffic and suburban sites in the region of Paris (France)". Science of The Total Environment 437 (octubre de 2012): 297–305. http://dx.doi.org/10.1016/j.scitotenv.2012.07.072.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

44

Kamiya, Yuta, Takayuki Kameda, Takeshi Ohura y Susumu Tohno. "Determination of Particle-Associated PAH Derivatives (ClPAHs, NPAHs, OPAHs) in Ambient Air and Automobile Exhaust by Gas Chromatography/Mass Spectrometry with Negative Chemical Ionization". Polycyclic Aromatic Compounds 37, n.º 2-3 (13 de julio de 2016): 128–40. http://dx.doi.org/10.1080/10406638.2016.1202290.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

45

Wei, Lijia, Jingya Lv, Peijie Zuo, Yingming Li, Ruiqiang Yang, Qinghua Zhang y Guibin Jiang. "The occurrence and sources of PAHs, oxygenated PAHs (OPAHs), and nitrated PAHs (NPAHs) in soil and vegetation from the Antarctic, Arctic, and Tibetan Plateau". Science of The Total Environment 912 (febrero de 2024): 169394. http://dx.doi.org/10.1016/j.scitotenv.2023.169394.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

46

Guo, Liqiong, Ziquan Liu, Penghui Li, Yaqin Ji, Shanjun Song, Na Zheng, Lei Zhao et al. "Association between mitochondrial DNA methylation and internal exposure to polycyclic aromatic hydrocarbons (PAHs), nitrated-PAHs (NPAHs) and oxygenated-PAHs (OPAHs) in young adults from Tianjin, China". Ecotoxicology and Environmental Safety 241 (agosto de 2022): 113799. http://dx.doi.org/10.1016/j.ecoenv.2022.113799.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

47

Li, Jingshu, Lingxiao Yang, Ying Gao, Pan Jiang, Yanyan Li, Tong Zhao, Junmei Zhang y Wenxing Wang. "Seasonal variations of NPAHs and OPAHs in PM2.5 at heavily polluted urban and suburban sites in North China: Concentrations, molecular compositions, cancer risk assessments and sources". Ecotoxicology and Environmental Safety 178 (agosto de 2019): 58–65. http://dx.doi.org/10.1016/j.ecoenv.2019.04.009.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

48

Xiao, Lingfeng, Song Hu, Yao Song, Liangping Zhang, Hengda Han, Changyi Liu, Long Jiang et al. "The formation mechanism for OPAHs during the cellulose thermal conversion in inert atmosphere at different temperatures based on ESI(−) FT-ICR MS measurement and density functional theory (DFT)". Fuel 239 (marzo de 2019): 320–29. http://dx.doi.org/10.1016/j.fuel.2018.10.113.

Texto completo

Los estilos APA, Harvard, Vancouver, ISO, etc.

49

Li, Jianjun, Qi Zhang, Gehui Wang, Jin Li, Can Wu, Lang Liu, Jiayuan Wang et al. "Optical properties and molecular compositions of water-soluble and water-insoluble brown carbon (BrC) aerosols in northwest China". Atmospheric Chemistry and Physics 20, n.º 8 (27 de abril de 2020): 4889–904. http://dx.doi.org/10.5194/acp-20-4889-2020.

Texto completo

Resumen

Abstract. Brown carbon (BrC) contributes significantly to aerosol light absorption and thus can affect the Earth's radiation balance and atmospheric photochemical processes. In this study, we examined the light absorption properties and molecular compositions of water-soluble (WS-BrC) and water-insoluble (WI-BrC) BrC in PM2.5 collected from a rural site in the Guanzhong Basin – a highly polluted region in northwest China. Both WS-BrC and WI-BrC showed elevated light absorption coefficients (Abs) in winter (4–7 times those in summer) mainly attributed to enhanced emissions from residential biomass burning (BB) for heating of homes. While the average mass absorption coefficients (MACs) at 365 nm (MAC365) of WS-BrC were similar between daytime and nighttime in summer (0.99±0.17 and 1.01±0.18 m2 g−1, respectively), the average MAC365 of WI-BrC was more than a factor of 2 higher during daytime (2.45±1.14 m2 g−1) than at night (1.18±0.36 m2 g−1). This difference was partly attributed to enhanced photochemical formation of WI-BrC species, such as oxygenated polycyclic aromatic hydrocarbons (OPAHs). In contrast, the MACs of WS-BrC and WI-BrC were generally similar in winter and both showed few diel differences. The Abs of wintertime WS-BrC correlated strongly with relative humidity, sulfate and NO2, suggesting that aqueous-phase reaction is an important pathway for secondary BrC formation during the winter season in northwest China. Nitrophenols on average contributed 2.44±1.78 % of the Abs of WS-BrC in winter but only 0.12±0.03 % in summer due to faster photodegradation reactions. WS-BrC and WI-BrC were estimated to account for 0.83±0.23 % and 0.53±0.33 %, respectively, of the total down-welling solar radiation in the ultraviolet (UV) range in summer, and 1.67±0.72 % and 2.07±1.24 %, respectively, in winter. The total absorption by BrC in the UV region was about 55 %–79 % relative to the elemental carbon (EC) absorption.

Los estilos APA, Harvard, Vancouver, ISO, etc.

50

Chen, T., R. J. Belland, J. Wilson y J. Swanson. "Adherence of pilus- Opa+ gonococci to epithelial cells in vitro involves heparan sulfate." Journal of Experimental Medicine 182, n.º 2 (1 de agosto de 1995): 511–17. http://dx.doi.org/10.1084/jem.182.2.511.

Texto completo

Resumen

Neisseria gonorrhoeae attaches to host epithelial cells via pili and opacity-associated (Opa) outer membrane proteins. Pilus- gonococci (Gc) of strain MS11 adhere to both human and nonhuman cells, but only when particular Opa proteins are expressed; OpaA+ variants adhere best, OpaC+ variants are next best, and the seven other Opa+ variants adhere poorly or not at all. The adherence of OpaA+ Gc to Chinese hamster ovary (CHO) cells is inhibited by heparin or heparan sulfate (HS), but not by chondroitin sulfate. OpaA+ Gc do not adhere to CHO cells devoid of HS proteoglycans; low concentrations of heparin restore OpaA+ Gc adherence to these HS-deficient CHO cells and high concentrations inhibit it. 3H-heparin binding to whole Gc parallels their adherence abilities (OpaA+ > OpaC+ > OpaH+ > Opas B, D, E, F, G, I = Opa- = 0). Opa proteins separated by SDS-PAGE also bind 3H-heparin. These data suggest that adherence of pilus-, Opa+ Gc involves HS-proteoglycan of eukaryotic cells.

Los estilos APA, Harvard, Vancouver, ISO, etc.

Ofrecemos descuentos en todos los planes premium para autores cuyas obras están incluidas en selecciones literarias temáticas. ¡Contáctenos para obtener un código promocional único!