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https://www.readbyqxmd.com/read/28944278/smoking-behavior-and-smoke-constituents-from-cigarillos-and-little-cigars
#1
Bartosz Koszowski, Zachary R Rosenberry, Daniel Yi, Sean Stewart, Wallace B Pickworth
OBJECTIVE: Although most cigarillos and little cigars smokers also smoke cigarettes (dual use), there are few studies comparing toxicant exposure and smoking behavior in cigars and cigarettes. METHODS: Two groups of dual users smoked their usual brand of cigarette and either a Winchester unflavored little cigar (N = 21) or a Black & Mild cigarillo (N = 23). Acute exposure of nicotine and exhaled carbon monoxide (CO) and puffing topography parameters were collected...
April 2017: Tobacco Regulatory Science
https://www.readbyqxmd.com/read/28943677/imaging-mercury-s-polar-deposits-during-messenger-s-low-altitude-campaign
#2
Nancy L Chabot, Carolyn M Ernst, David A Paige, Hari Nair, Brett W Denevi, David T Blewett, Scott L Murchie, Ariel N Deutsch, James W Head, Sean C Solomon
Images obtained during MESSENGER's low-altitude campaign in the final year of the mission provide the highest-spatial-resolution views of Mercury's polar deposits. Images for distinct areas of permanent shadow within 35 north polar craters were successfully captured during the campaign. All of these regions of permanent shadow were found to have low-reflectance surfaces with well-defined boundaries. Additionally, brightness variations across the deposits correlate with variations in the biannual maximum surface temperature across the permanently shadowed regions, supporting the conclusion that multiple volatile organic compounds are contained in Mercury's polar deposits, in addition to water ice...
September 28, 2016: Geophysical Research Letters
https://www.readbyqxmd.com/read/28942560/keto-ether-and-glycol-ethers-in-the-troposphere-reactivity-toward-oh-radicals-and-cl-atoms-global-lifetimes-and-atmospheric-implications
#3
Javier A Barrera, Pablo R Dalmasso, Raúl A Taccone, Silvia I Lane
Rate coefficients for the gas-phase reactions of OH radicals and Cl atoms with 1-methoxy-2-propanone (1-M-2-PONE), 1-methoxy-2-propanol (1-M-2-POL), and 1-methoxy-2-butanol (1-M-2-BOL) were determined at room temperature and atmospheric pressure using a conventional relative-rate technique. The following absolute rate coefficients were derived: k 1(OH + 1-M-2-PONE) = (0.64 ± 0.13) × 10(-11), k 2(OH + 1-M-2-BOL) = (2.19 ± 0.23) × 10(-11), k 3(Cl + 1-M-2-PONE = (1.07 ± 0.24) × 10(-10), k 4(Cl + 1-M-2-POL) = (2...
September 23, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28942244/kinetic-product-and-computational-studies-of-the-ultrasonic-induced-degradation-of-4-methylcyclohexanemethanol-mchm
#4
Danni Cui, Alexander M Mebel, Luis E Arroyo-Mora, Howard Holness, Kenneth G Furton, Kevin O'Shea
A massive spill of 4-methylcyclohexanemethanol (MCHM), a semi-volatile organic compound, contaminated the Elk river and forced the recent closure of tap water for nearly 300,000 residents. Typical water treatment methods are not effective for MCHM remediation, however ultrasonic irradiation leads to its rapid pseudo-first order degradation. The degradation processes were effectively modeled employing heterogeneous kinetic models with the reaction surface corresponding to the gas-liquid interface of the cavitation bubble...
September 5, 2017: Water Research
https://www.readbyqxmd.com/read/28942192/emissions-of-volatile-organic-compounds-during-the-ship-loading-of-petroleum-products-dispersion-modelling-and-environmental-concerns
#5
Maria Francesca Milazzo, Giuseppa Ancione, Roberto Lisi
Emissions due to ship-loading of hydrocarbons are currently not addressed neither by the Directive on the integrated pollution prevention or by other environmental regulations. The scope of this study is to point towards the environmental and safety concerns associated with such emissions, even if proper attention has not been given to this issue until now. In order to achieve this goal, the modelling of the emission volatile organic compounds (VOC), due to ship-load operations at refineries has been made by means of the definition of a simulation procedure which includes a proper treatment of the hours of calm...
September 21, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28941718/a-multi-year-study-of-voc-emissions-at-a-chemical-waste-disposal-facility-using-mobile-apci-ms-and-lpci-ms-instruments
#6
Robert M Healy, QingFeng Chen, Julie Bennett, Nicholas S Karellas
Real-time analysis of volatile organic compounds (VOCs) in air is useful both for source identification and emissions compliance applications. In this work, two complementary triple quadrupole mass spectrometers, fitted with an atmospheric pressure chemical ionization (APCI) and a low pressure chemical ionization (LPCI) source, respectively, were deployed simultaneously to investigate emissions of VOCs associated with an Ontario-based chemical waste disposal facility. Mobile measurements performed upwind and downwind of the facility enabled selection of the best locations for stationary sampling...
September 20, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28937162/experimentally-validated-mathematical-model-of-analyte-uptake-by-permeation-passive-samplers
#7
F Salim, M Ioannidis, T Górecki
A mathematical model describing the sampling process in a permeation-based passive sampler was developed and evaluated numerically. The model was applied to the Waterloo Membrane Sampler (WMS), which employs a polydimethylsiloxane (PDMS) membrane as a permeation barrier, and an adsorbent as a receiving phase. Samplers of this kind are used for sampling volatile organic compounds (VOC) from air and soil gas. The model predicts the spatio-temporal variation of sorbed and free analyte concentrations within the sampler components (membrane, sorbent bed and dead volume), from which the uptake rate throughout the sampling process can be determined...
September 22, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28936271/comparison-of-the-volatile-organic-compound-recovery-rates-of-commercial-active-samplers-for-evaluation-of-indoor-air-quality-in-work-environments
#8
Yuichi Miyake, Masahiro Tokumura, Qi Wang, Zhiwei Wang, Takashi Amagai
The Industrial Safety and Health Law in Japan established administrative levels for volatile organic compounds (VOCs) in indoor air. In the present study, these 49 VOCs were extracted from the absorbents of commercial active samplers from Sibata Scientific Technology (carbon-bead active sampler), SKC Inc. (Anasorb CSC sorbent tube), and Gastec (bead-shaped activated carbon tube) using carbon disulfide, and the recovery rates were compared. The VOCs were added to the adsorbents at three concentration levels relative to the administrative levels (×0...
2017: Air Quality, Atmosphere, & Health
https://www.readbyqxmd.com/read/28935261/optimization-of-the-solvent-based-dissolution-method-to-sample-volatile-organic-compound-vapors-for-compound-specific-isotope-analysis
#9
Daniel Bouchard, Philipp Wanner, Hong Luo, Patrick W McLoughlin, James K Henderson, Robert J Pirkle, Daniel Hunkeler
The methodology of the solvent-based dissolution method used to sample gas phase volatile organic compounds (VOC) for compound-specific isotope analysis (CSIA) was optimized to lower the method detection limits for TCE and benzene. The sampling methodology previously evaluated by [1] consists in pulling the air through a solvent to dissolve and accumulate the gaseous VOC. After the sampling process, the solvent can then be treated similarly as groundwater samples to perform routine CSIA by diluting an aliquot of the solvent into water to reach the required concentration of the targeted contaminant...
August 24, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28932891/identification-of-terpenes-and-essential-oils-by-means-of-static-headspace-gas-chromatography-ion-mobility-spectrometry
#10
Roman Rodríguez-Maecker, Eduardo Vyhmeister, Stefan Meisen, Antonio Rosales Martinez, Andriy Kuklya, Ursula Telgheder
Static headspace gas chromatography-ion mobility spectrometry (SHS GC-IMS) is a relatively new analytical technique that has considerable potential for analysis of volatile organic compounds (VOCs). In this study, SHS GC-IMS was used for the identification of the major terpene components of various essential oils (EOs). Based on the data obtained from 25 terpene standards and 50 EOs, a database for fingerprint identification of characteristic terpenes and EOs was generated utilizing SHS GC-IMS for authenticity testing of fragrances in foods, cosmetics, and personal care products...
September 20, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28931931/screening-of-obstructive-sleep-apnea-syndrome-by-electronic-nose-analysis-of-volatile-organic-compounds
#11
Simone Scarlata, Giorgio Pennazza, Marco Santonico, Simona Santangelo, Isaura Rossi Bartoli, Chiara Rivera, Chiara Vernile, Antonio De Vincentis, Raffaele Antonelli Incalzi
Obstructive Sleep Apnea Syndrome (OSAS) carries important social and economic implications. Once the suspicion of OSAS has arisen, Polysomnography (PSG) represents the diagnostic gold standard. However, about 45% of people who have undergone PSG are free from OSAS. Thus, efforts should be made to improve the selection of subjects. We verified whether the pattern of Volatile Organic Compounds (VOCs) helps to select patients amenable to PSG. We studied 136 subjects (20 obese non-OSAS, 20 hypoxic OSAS, 20 non-hypoxic OSAS, and 20 non-hypoxic Chronic Obstructive Pulmonary Disease (COPD) vs 56 healthy controls) without any criteria of exclusion for comorbidity to deal with a real-life population...
September 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28930472/light-absorption-of-secondary-organic-aerosol-composition-and-contribution-of-nitro-aromatic-compounds
#12
Mingjie Xie, Xi Chen, Michael D Hays, Michael Lewandowski, John H Offenberg, Tadeusz Edward Kleindienst, Amara Holder
Secondary organic aerosol (SOA) might affect the atmospheric radiation balance through absorbing light at shorter visible and UV wavelengths. However, the composition and optical properties of light-absorbing SOA is poorly understood. In this work, SOA filter samples were collected during individual chamber experiments with three biogenic and eight aromatic volatile organic compound (VOC) precursors in the presence of NOX and H2O2. Compared with the SOA generated using the aromatic precursors, biogenic SOA in general exhibits negligible light absorption above 350 nm; the aromatic SOA generated in the presence of NOX showed stronger light absorption than that generated with H2O2...
September 20, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28930245/antioxidant-and-antimicrobial-activities-of-the-essential-oil-of-achillea-millefolium-l-grown-in-france
#13
Chaker El-Kalamouni, Petras Rimantas Venskutonis, Bachar Zebib, Othmane Merah, Christine Raynaud, Thierry Talou
Background: This study aimed to examine the composition of essential oil (EO) of A. millefolium aerial parts wild plant grown in France and evaluate its antioxidant, antibacterial, and antifungal activities. Methods: GC-MS was used to identify the chemical composition of EO. Antioxidant activity (AA) of EO was evaluated by Oxipres method. Antimicrobial activity of EO was evaluated by Agar-well diffusion and a broth microdilution assay. Results: Forty-three volatile compounds were identified. Major compounds were camphor (12...
May 19, 2017: Medicines (Basel, Switzerland)
https://www.readbyqxmd.com/read/28925377/applied-upper-airway-resistance-instantly-affects-breath-components-a-unique-insight-into-pulmonary-medicine
#14
Pritam Sukul, Jochen Schubert, Svend Kamysek, Phillip Trefz, Wolfram Miekisch
Respiratory parameters such as flow or rate have complex effects onto exhalation of volatile substances and can hamper clinical interpretation of breath biomarkers. We investigated effects of progressively applied upper-airway resistances onto exhalation of volatile organic compounds (VOCs) in healthy humans. We performed real-time mass-spectrometric determination of breath volatiles in 50 subjects with parallel non-invasive hemodynamic monitoring, breath-resolved spirometry and capnometry during controlled tidal breathing (12 breaths/min)...
September 19, 2017: Journal of Breath Research
https://www.readbyqxmd.com/read/28924742/characterization-of-pm2-5-in-delhi-role-and-impact-of-secondary-aerosol-burning-of-biomass-and-municipal-solid-waste-and-crustal-matter
#15
Pavan K Nagar, Dhirendra Singh, Mukesh Sharma, Anil Kumar, Viney P Aneja, Mohan P George, Nigam Agarwal, Sheo P Shukla
Delhi is one among the highly air polluted cities in the world. Absence of causal relationship between emitting sources of PM2.5 and their impact has resulted in inadequate actions. This research combines a set of innovative and state-of-the-art analytical techniques to establish relative predominance of PM2.5 sources. Air quality sampling at six sites in summer and winter for 40 days (at each site) showed alarmingly high PM2.5 concentrations (340 ± 135 μg/m(3)). The collected PM2.5 was subjected to chemical speciation including ions, metals, organic and elemental carbons which followed application of chemical mass balance technique for source apportionment...
September 18, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28922624/quantification-of-voc-emissions-from-paint-spraying-on-a-construction-site-using-solid-phase-microextraction-devices
#16
Wen-Hsi Cheng, Hsiao-Lin Huang, Kang-Shin Chen, Yu-Jen Chang
The objective of this study was to measure the emission of, and personal exposure to workers, volatile organic compound (VOC) during paint spraying on a construction site. Needle trap samplers (NTSs), which are a green solid phase microextraction sampling technology, were used to obtain air samples at a large music exhibition center. The standard active sampling method using charcoal tubes and a personal air pump, Method 1501, was simultaneously utilized at the sampling sites to assess the workers' VOC exposures...
September 18, 2017: Journal of Environmental Science and Health. Part A, Toxic/hazardous Substances & Environmental Engineering
https://www.readbyqxmd.com/read/28918281/distribution-of-vocs-in-urban-and-rural-atmospheres-of-subtropical-india-temporal-variation-source-attribution-ratios-ofp-and-risk-assessment
#17
Amit Kumar, Deepak Singh, Krishan Kumar, Braj Bihari Singh, Vinod Kumar Jain
This paper reports the first study which comprises the seasonal, diurnal variability, source characterization, ozone forming potential and risk assessment of volatile organic compounds (VOCs) at three sites (two urban and one rural) in the National Capital Territory of Delhi, India. The study was performed during three seasons of the year 2013-14 and two different categories of VOCs (aromatics and halogenated) have been selected. The study used the sampling and analytical procedures of NIOSH methods. Results showed that the mean concentration of sum of VOCs (∑VOC) is significantly higher at urban sites (110...
September 14, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28918273/volatile-and-semivolatile-emissions-from-the-pyrolysis-of-almond-shell-loaded-with-heavy-metals
#18
M A Martín-Lara, N Ortuño, J A Conesa
Heavy metal-loaded almond shell was subjected to pyrolysis to understand the effect of the presence of different heavy metals on its thermal degradation. Pyrolysis behavior of native and metal-loaded samples was studied by thermogravimetric analysis. Similar shapes of thermogravimetric curves indicate that the presence of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and lead (Pb) did not change the main degradation pathways of almond shell. However, the temperature at which the decomposition in each stage takes place at a higher rate and char yield was considerably modified by the presence of Cr and Ni...
September 14, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28918122/pre-harvest-uv-c-irradiation-triggers-vocs-accumulation-with-alteration-of-antioxidant-enzymes-and-phytohormones-in-strawberry-leaves
#19
Yanqun Xu, Zisheng Luo, Marie Thérèse Charles, Daniel Rolland, Dominique Roussel
Recent studies have highlighted the biological and physiological effects of pre-harvest ultraviolet (UV)-C treatment on growing plants. However, little is known about the involvement of volatile organic compounds (VOCs) and their response to this treatment. In this study, strawberry plants were exposed to three different doses of UV-C radiation for seven weeks (a low dose: 9.6kJm(-2); a medium dose: 15kJm(-2); and a high-dose: 29.4kJm(-2)). Changes in VOC profiles were investigated and an attempt was made to identify factors that may be involved in the regulation of these alterations...
September 8, 2017: Journal of Plant Physiology
https://www.readbyqxmd.com/read/28917787/gas-chromatographic-mass-spectrometric-analysis-of-urinary-volatile-organic-metabolites-optimization-of-the-hs-spme-procedure-and-sample-storage-conditions
#20
Tanja Živković Semren, Irena Brčić Karačonji, Toni Safner, Nataša Brajenović, Blanka Tariba Lovaković, Alica Pizent
Non-targeted metabolomics research of human volatile urinary metabolome can be used to identify potential biomarkers associated with the changes in metabolism related to various health disorders. To ensure reliable analysis of urinary volatile organic metabolites (VOMs) by gas chromatography-mass spectrometry (GC-MS), parameters affecting the headspace-solid phase microextraction (HS-SPME) procedure have been evaluated and optimized. The influence of incubation and extraction temperatures and times, coating fibre material and salt addition on SPME efficiency was investigated by multivariate optimization methods using reduced factorial and Doehlert matrix designs...
January 1, 2018: Talanta
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