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In this study, samples were taken of the surface dust of main roads in Xinxiang City, and the concentrations of five heavy metals (Cd, Pb, Cr, Cu and Zn) and fifteen polycyclic aromatic hydrocarbons (PAHs) were determined by inductively coupled plasma mass spectrometry (ICP-MS) and gas chromatography-mass spectrometry (GC-MS), respectively. Meanwhile, the effects of vehicle emissions on the pollution characteristics were investigated. The results showed that the concentrations of heavy metals and PAHs ranged from 2.58 to 1560 mg·kg

Surface water samples were collected in the middle reaches of the Yellow River (Weinan-Zhengzhou section) and all 28 perfluoroalkyl and polyfluoroalkyl substance (PFAS) levels were measured using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The results show that the levels of PFASs in the water and particle phase are 18.4-56.9 ng·L

Atmospheric gaseous and particle samples were collected using high-volume active samplers in Guangzhou and Wuzhishan. Concentrations of all the eight selected new halogenated flame retardants (NHFRs), including

Four types of dust from dormitories, offices, hotels and roads in Beijing were collected and fractionated into 9 fractions, respectively. Totally 36 samples were obtained and analyzed for heavy metals including Cu, Zn, Cr, Pb, Cd and Ni. Particle size distributions of those heavy metals in these four types of dust were investigated and the influencing mechanisms were discussed. Distribution patterns of the same heavy metal in different types of dust showed various characteristics. Also different metals in the same type of dust represented different distribution patterns. Heavy metals in road dust tended to concentrate in finer particles. Two offices from the same building, located in Beijing, China, were selected to study the seasonality of heavy metals in dust. Dust sampling from Office A was conducted at weekly intervals between March 2012 and August 2012, while dust from Office B was sampled fortnightly from March 2012 to December 2012. Generally, levels of all heavy metals remained stable among different seasons, however, Cr and Pb represented more significant fluctuations than other four heavy metals. Based on the geo-accumulation index method, the pollution of Zn, Cu and Pb was more serious in the investigated samples, and dust from offices and hotels were moderately polluted by Zn. According to the risk assessment results, the carcinogenic health risks of the six heavy metals in the four types of dust were negligible.

The gas and particle samples of eight cities were collected by high flow active air sampler in the Eastern and Western China and eight congeners of polybrominated diphenyl ethers were analyzed. The results showed that the concentration of BDE-28 (tri-BDE) in the gas-phase (three bromide components) was the highest, which was different from previous studies where BDE-99 and-47 were the predominant homologues in the gas-phase while the concentration of BDE-209 [(25.4 ± 124) pg · m⁻³] in particle-phase was the highest. The atmospheric concentrations of PBDEs in Beijing and Guangzhou were relatively higher, especially the BDE-209 concentration in particle phases of Guangzhou was two orders higher than those of other cities. However, the atmospheric concentrations of PBDEs declined significantly when compared with the data from previous studies. Meanwhile, the results indicated that the gas-phase concentrations decreased slowly and the particle-phase concentrations decreased rapidly. Combined with the results of correlation analysis, this phenomenon might be ascribed to the ceased commercial production of penta- and octa-BDE, the light degradation of high bromide components and reduced concentrations of atmospheric particles in urban area. Inhalation exposure for infants was about 2-3 times higher than that of adults. This reflected that the potential health risk of atmospheric PBDEs in city for residents, especially infants and young children, should not be ignored.

To rapidly identify Metoprolol Tartrate tablets from different manufacturers, a qualitative analysis model can be established by near infrared spectroscopy. Firstly, AntarisII Fourier-transform near infrared (FT-NIR) spectroscopy and Micro NIR1700 Spectrometer were used to collect spectral data of 66 batches of samples which come from four different manufacturers, then 44 samples of calibration set and 22 samples of validation set were acquired by random sampling. In order to build up a PLS-DA model, the first derivative with Savitzky-Golay 15 points smoothing (1d+SG15) and standard normal vitiate transformation (SNV) was selected as the pretreatment method and according to the variation between different samples and the characteristic absorption band, 6 468-7 104 cm(-1) and 6 468-7 156 cm(-1) were chosen as the modeling spectra region. The confusion matrix indicated that Metoprolol Tartrate tablets could be rapidly and effectively identified by two analytical models, which were established using the spectral data collected from two instruments. For these two models, both of the sensitivity and specificity were 100%. This study confirmed that it is feasible to carry out the manufacturer identification of Metoprolol Tartrate tablets by near infrared spectroscopy. Besides, the use of Micro NIR1700 Spectrometer, which is the minimum and portable near infrared spectrometer, provides valuable insights for fast on-site drug screening.

A total of 32 air samples collected during a Shiyan III voyage over the northern South China Sea (SCS) were analyzed for polybrominated diphenyl ethers (PBDEs) by gas chromatography/mass spectrometry. The concentrations of sigma 7 PBDEs ranged from 0.07 to 35.9 pg x m(-3). The sigma 7 PBDEs were dominated by tetra-(BDE-47) and penta-(BDE-99 and -100) components, which accounted for 51.5% and 36.9%, respectively. This result indicated that the widely used commercial penta-BDE product was the original source. The higher concentrations of PBDEs were monitored close to the coastline of the South China and Philippine, while the lower concentrations were found over the SCS adjacent to central coast of Vietnam. Back trajectory analysis showed that the high PBDE concentrations observed in air over the northern SCS may be related to the continental pollutant outflows from the southeast coast of China, especially the Pearl River Delta, Taiwan and Philippine, by prevailing northeast wind transport.