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A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determining four tobacco-specific N-nitrosamines (TSNAs) in mainstream smoke from Chinese Virginia cigarettes was developed. Mainstream cigarette smoke particulate matter was collected on a Cambridge filter pad, further extracted using 100 mM ammonium acetate after 100 microL internal(More)
A multiresidue gas chromatography-tandem mass spectrometry (GC-MS/MS) method was developed for the analysis of 159 multiclass pesticides in tobacco. A modified QuEChERS sample preparation technique, based on acetonitrile extraction and toluene dilution, followed by dispersive solid-phase extraction (d-SPE) cleanup using primary-secondary amine (PSA) and(More)
A simple and sensitive high performance liquid chromatography-tandem mass spectrometry (HPLC-ESI-MS-MS) method was developed and validated for the quantification of creatinine in human urine. The analysis was carried out on an Agilent Zorbax Eclipse XDB-C18 column (2.1 × 150 mm, 3.5 μm). The mobile phase was 0.1% formic acid in water and 0.1% formic acid in(More)
1,3-Butadiene (BD) is a ubiquitous environmental pollutant found in tobacco smoke. In vivo, BD is mainly metabolized to form monohydroxybutenylmercapturic acid (MHBMA) and N-acetyl-S-(3, 4-dihydroxybutyl) cysteine (DHBMA). The accurate quantification of MHBMA and DHBMA in urine may provide important insights into the actual internal exposure of the general(More)
High surface area microporous carbon materials were synthesized using new, simple, and innovative approaches based on traditional template and chemical activation methods. The resulting surface area and porosity were characterized using Brunauer-Emmett-Teller (BET)-type measurements and analysis, and the hydrogen storage capacity was determined using excess(More)
The electrostrictive effect has some advantages over the piezoelectric effect, including temperature stability and hysteresis-free character. In the present work, we report the diffuse phase transitions and electrostrictive properties in lead-free Fe(3+)-doped 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-0.5BCT) ferroelectric ceramics. The doping(More)
Heavy metals in tobacco caused wide public concern. To study the impact of heavy metals in smokers, 193 smokers and 58 nonsmokers were surveyed, and their urinary levels of chromium (UCr), lead (UPb), and cadmium (UCd) were assayed. In this study, UCr, UPb, and UCd in smokers (33.41 ± 14.99, 3.21 ± 1.34, 0.38 ± 0.64 μg/24 h, respectively) and nonsmokers(More)
The transcription regulator PbrR691, one of the MerR family proteins, shows extremely high sensitivity and selectivity toward Pb(II) in Ralstonia metallidurans CH34. Here, we present the crystal structure of PbrR691 in complex with Pb(II) at 2.0 Å resolution. The Pb(II) coordinates with three conserved cysteines and adopts a unique trigonal-pyramidal(More)