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Volatile organic compounds

Kyle D Custard, Kerri A Pratt, Siyuan Wang, Paul B Shepson
During springtime, unique halogen chemistry involving chlorine and bromine atoms controls the prevalence of volatile organic compounds, ozone, and mercury in the Arctic lower troposphere. In situ measurements of the chlorine monoxide radical (ClO) and its precursor Cl2, along with BrO and Br2, were conducted using chemical ionization mass spectrometry (CIMS) during the BRomine, Ozone, and Mercury EXperiment (BROMEX) near Barrow, Alaska in March 2012. To our knowledge, these data represent the first ClO measurements made using CIMS...
October 21, 2016: Environmental Science & Technology
Dong Bok Jeon, Young Shin Hong, Ga Hyun Lee, Yu Min Park, Cheong Mi Lee, Eun Yeong Nho, Ji Yeon Choi, Nargis Jamila, Naeem Khan, Kyong Su Kim
Tea contains characteristic volatile organic compounds, polyphenols, caffeine and catechins, and is therefore among the most widely consumed beverages all over the world. In this study, fresh Jukro tea leaves collected from Damyang-gun (Jeollanam-do) at 40, 60 and 90day growth stages, were semi-fermented. The volatile organic compounds (VOCs) were extracted by simultaneous distillation-solvent extraction (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS). Catechins, caffeine and theanine were analyzed by high performance liquid chromatography (HPLC)...
March 15, 2017: Food Chemistry
Jing Li, Tengfei Fan, Yong Xu, Xuemin Wu
Emulsifiers for pesticide microemulsions contain a part of volatile organic compounds (VOCs), and ionic liquids (ILs) are becoming potential substitutes. In order to apply ILs in pesticide microemulsions, the study of interaction between ILs and surfactants is necessary. Therefore, the surface properties and aggregation of anionic surfactant sodium dodecyl sulfate (SDS) in ILs, including N-hexyl-N-methylmorpholinyl bromide ([C6mm][Br]), N-hexyl-N-methylpiperidyl bromide ([C6mp][Br]), N-hexyl-N-methylpyrrolidyl bromide ([C6mpyr][Br]), N-octyl-N-methylpyrrolidyl bromide ([C8mpyr][Br]), N-dodecyl-N-methylpyrrolidyl bromide ([C12mpyr][Br]) and N-hexadecyl-N-methylpyrrolidyl bromide ([C16mpyr][Br]), were investigated in terms of surface tension, conductivity, dynamic light scattering (DLS), viscosity, fluorescence, pseudo-ternary phase diagram and (1)H NMR measurements...
October 19, 2016: Physical Chemistry Chemical Physics: PCCP
Laura Capelli, Gianluigi Taverna, Alessia Bellini, Lidia Eusebio, Niccolò Buffi, Massimo Lazzeri, Giorgio Guazzoni, Giorgio Bozzini, Mauro Seveso, Alberto Mandressi, Lorenzo Tidu, Fabio Grizzi, Paolo Sardella, Giuseppe Latorre, Rodolfo Hurle, Giovanni Lughezzani, Paolo Casale, Sara Meregali, Selena Sironi
The electronic nose is able to provide useful information through the analysis of the volatile organic compounds in body fluids, such as exhaled breath, urine and blood. This paper focuses on the review of electronic nose studies and applications in the specific field of medical diagnostics based on the analysis of the gaseous headspace of human urine, in order to provide a broad overview of the state of the art and thus enhance future developments in this field. The research in this field is rather recent and still in progress, and there are several aspects that need to be investigated more into depth, not only to develop and improve specific electronic noses for different diseases, but also with the aim to discover and analyse the connections between specific diseases and the body fluids odour...
October 14, 2016: Sensors
Marika Rai, David Spratt, Paola R Gomez-Pereira, Jay Patel, Sean P Nair
Oral malodour is a common condition which affects a large proportion of the population, resulting in social, emotional and psychological stress. Certain oral bacteria form a coating called a biofilm on the tongue dorsum and degrade organic compounds releasing volatile sulfur compounds that are malodourous. Current chemical treatments for oral malodour such as mouthwashes containing chlorhexidine or essential oils, are not sufficiently effective at reducing the bacterial load on the tongue. One potential alternative to current chemical treatments for oral malodour is the use of light activated antimicrobial agents (LAAAs), which display no toxicity or antimicrobial activity in the dark, but when exposed to light of a specific wavelength produce reactive oxygen species which induce damage to target cells in a process known as photodynamic inactivation...
October 18, 2016: Journal of Breath Research
Sang Pil Hong, Eun Joo Lee, Young Ho Kim, Dong Uk Ahn
This study was conducted to evaluate the effect of fermentation temperature on the volatile composition in Kimchi. Kimchi was fermented at 2 temperature conditions (4 and 20 °C). Volatile compounds of Kimchi samples were analyzed during the fermentation periods using the dynamic headspace gas chromatography-mass spectrometry method. The optimum ripening time for the Kimchi fermented at 4 °C was 35 d, and that of 20 °C was 2 d. The pH at the optimum ripening time was 4.97 and 4.41, and the titratable acidity was 0...
October 17, 2016: Journal of Food Science
Anandram Venkatasubramanian, Vincent T K Sauer, Swapan K Roy, Mike Xia, David S Wishart, Wayne K Hiebert
Micro-Gas Chromatography (GC) is promising for portable chemical analysis. We demonstrate a nano-optomechanical system (NOMS) as an ultrasensitive mass detector in gas chromatography. Bare, native oxide, silicon surfaces are sensitive enough to monitor volatile organic compounds at ppm levels, while simultaneously demonstrating chemical selectivity. The NOMS is able to sense GC peaks from derivatized metabolites at physiological concentrations. This is an important milestone for small-molecule quantitation assays in next generation metabolite analyses for applications such as disease diagnosis and personalized medicine...
October 17, 2016: Nano Letters
Guozhu Zhao, Guohua Yin, Arati A Inamdar, Jing Luo, Ning Zhang, Ill Yang, Brian Buckley, Joan W Bennett
Super Storm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to 8 genera: Penicillium (12 species), Fusarium (4 species), Aspergillus (3 species), Trichoderma (2 species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis...
October 17, 2016: Indoor Air
Kenion H Blakeman, Craig A Cavanaugh, William M Gilliland, J Michael Ramsey
RATIONALE: There are many chemical measurement scenarios that would benefit from hand portable mass spectrometry tools including forensics, environmental monitoring, and safety and security. High pressure mass spectrometry (HPMS) facilitates miniaturization by significantly reducing vacuum system requirements. Previous work demonstrated HPMS using helium buffer gas, but HPMS conducted using ambient air would further reduce the size and weight of a portable instrument while also reducing logistical demands by eliminating the need for a helium supply...
October 17, 2016: Rapid Communications in Mass Spectrometry: RCM
Charlie E Kivi, Datong Song
A new metal-organic framework (1) constructed from 4-(4-(3,5-dimethyl-1H-pyrazol-4-yl)phenyl)pyridine (HL) and CuBr shows potential as a luminescent sensor for volatile organic compounds.
October 17, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Jin-Lian Chen, Shi-Zhong Sun, Cui-Ping Miao, Kai Wu, You-Wei Chen, Li-Hua Xu, Hui-Lin Guan, Li-Xing Zhao
BACKGROUND: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. METHODS: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T...
October 2016: Journal of Ginseng Research
Guiqian Tang, Na Chao, Yuesi Wang, Jiashan Chen
Vehicular emissions in China in 2006 and 2010 were calculated at a high spatial resolution based on the data released by the National Bureau of Statistics, by taking the emission standards into consideration. China's vehicular emissions of carbon monoxide (CO), nitrogen oxides (NOx), volatile organic compounds (VOCs), ammonia (NH3), fine particulate matters (PM2.5), inhalable particulate matters (PM10), black carbon (BC), and organic carbon (OC) were 30,113.9, 4593.7, 6838.0, 20.9, 400.2, 430.5, 285.6, and 105...
October 2016: Journal of Environmental Sciences (China)
Qinghuan Xu, Lin Yang, Wangting Yang, Yan Bai, Ping Hou, Jingxian Zhao, Lv Zhou, Zhaojiang Zuo
Eutrophication promotes massive growth of cyanobacteria and algal blooms, which can poison other algae and reduce biodiversity. To investigate the differences in multiple nitrogen (N) sources in eutrophicated water on the emission of volatile organic compounds (VOCs) from cyanobacteria, and their toxic effects on other algal growth, we analyzed VOCs emitted from Microcystis flos-aquae with different types and concentrations of nitrogen, and determined the effects under Normal-N and Non-N conditions on Chlorella vulgaris...
October 11, 2016: Ecotoxicology and Environmental Safety
Cleyton Martins da Silva, Luane Lima da Silva, Sergio Machado Corrêa, Graciela Arbilla
Volatile organic compounds (VOCs) play a central role in atmospheric chemistry. In this work, the kinetic and mechanistic reactivities of VOCs are analyzed, and the contribution of the organic compounds emitted by anthropogenic and natural sources is estimated. VOCs react with hydroxyl radicals and other photochemical oxidants, such as ozone and nitrate radicals, which cause the conversion of NO to NO2 in various potential reaction paths, including photolysis, to form oxygen atoms, which generate ozone. The kinetic reactivity was evaluated based on the reaction coefficients for hydroxyl radicals with VOCs...
October 13, 2016: Bulletin of Environmental Contamination and Toxicology
Miyuki Noguchi, Saya Tanaka, Kaede Watanabe, Akihiro Yamasaki
We examined the correlation between the odor concentration and the chemical composition of environmental tobacco smoke (ETS). Three types of ETS samples were prepared: secondhand smoke (SHS), thirdhand smoke (THS), and field ETS samples from an outside smoking area. The odor concentrations of the ETS, SHS, and THS samples were determined by the triangle-odor-bag method, and the chemical compositions were determined by proton transfer mass spectrometry. The odor concentration of the SHS samples was three or four orders of magnitude higher than that of the field ETS samples, and three orders of magnitude higher than that of the THS samples...
October 9, 2016: International Journal of Environmental Research and Public Health
Ivan Kourtchev, Chiara Giorio, Antti Manninen, Eoin Wilson, Brendan Mahon, Juho Aalto, Maija Kajos, Dean Venables, Taina Ruuskanen, Janne Levula, Matti Loponen, Sarah Connors, Neil Harris, Defeng Zhao, Astrid Kiendler-Scharr, Thomas Mentel, Yinon Rudich, Mattias Hallquist, Jean-Francois Doussin, Willy Maenhaut, Jaana Bäck, Tuukka Petäjä, John Wenger, Markku Kulmala, Markus Kalberer
Secondary organic aerosol (SOA) accounts for a dominant fraction of the submicron atmospheric particle mass, but knowledge of the formation, composition and climate effects of SOA is incomplete and limits our understanding of overall aerosol effects in the atmosphere. Organic oligomers were discovered as dominant components in SOA over a decade ago in laboratory experiments and have since been proposed to play a dominant role in many aerosol processes. However, it remains unclear whether oligomers are relevant under ambient atmospheric conditions because they are often not clearly observed in field samples...
October 13, 2016: Scientific Reports
Sean W Harshman, Nilan Mani, Brian A Geier, Jae Kwak, Phillip Shepard, Maomian Fan, Gregory L Sudberry, Ryan S Mayes, Darrin K Ott, Jennifer A Martin, Claude C Grigsby
Exhaled breath is coming to the forefront of non-invasive biomarker discovery efforts. Concentration of exhaled breath volatile organic compounds (VOCs) on thermal desorption (TD) tubes with subsequent analysis by gas chromatography-mass spectrometry (GC-MS) has dominated this field. As discovery experimentation increases in frequency, the need to evaluate the long-term storage stability of exhaled breath VOCs on thermal desorption adsorbent material is critical. To address this gap, exhaled breath was loaded on Tenax TA thermal desorption tubes and stored at various temperature conditions...
October 12, 2016: Journal of Breath Research
Kristin Schallschmidt, Roland Becker, Christian Jung, Wolfram Bremser, Thorsten Walles, Jens Neudecker, Gunda Leschber, Steffen Frese, Irene Nehls
This paper outlines the design and performance of an observational study on the profiles of volatile organic compounds (VOCs) in the breath of 37 lung cancer patients and 23 healthy controls of similar age. The need to quantify each VOC considered as a potential disease marker on the basis of individual calibration is elaborated, and the quality control measures required to maintain reproducibility in breath sampling and subsequent instrumental trace VOC analysis using solid phase microextraction-gas chromatography-mass spectrometry over a study period of 14 months are described...
October 12, 2016: Journal of Breath Research
Philip B Pedros, Omid Askari, Hameed Metghalchi
During the last decade municipal wastewater treatment plants have been regulated with increasingly stringent nutrient removal requirements including nitrogen. Typically biological treatment processes are employed to meet these limits. Although the nitrogen in the wastewater stream is reduced, certain steps in the biological processes allow for the release of gaseous nitrous oxide (N2O), a greenhouse gas (GHG). A comprehensive study was conducted to investigate the potential to mitigate N2O emissions from biological nutrient removal (BNR) processes by means of thermal decomposition...
October 4, 2016: Water Research
Rongyu Zhuang, Yongjiang Lou, Xiaoting Qiu, Yangyong Zhao, Dong Qian, Xiaojun Yan, Xiaodie He, Qingqing Shen, Lizhen Qian
Hydrogen sulfide is a common odor gas of volatile sulfur-containing compound. The emission of hydrogen sulfide in the waste gas from industrial processing and agricultural operations could cause air pollution to the surrounding environment. The aim of this study was screening and isolation of wild yeast strains from the sludge of sewage pool in the fishmeal processing plant to remove hydrogen sulfide odor. A yeast strain ZJY-7 was obtained. Its hydrogen sulfide removal efficiency was 97.1 %. The morphology studies were investigated using microscope and scanning electron microscope...
October 10, 2016: Applied Microbiology and Biotechnology
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