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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.
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Metoprolol , Comprimidos , Calibración , Modelos Teóricos , Espectroscopía Infrarroja por Transformada de Fourier , Espectroscopía Infrarroja CortaRESUMEN
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-1 and 26.8-164 ng·g-1, respectively. Perfluorohexanoic acid (PFHxA) in the water and particle phases is the main pollutant, accounting for 27% and 16% of the total concentrations, respectively, and 3H-perfluoro-3-[(3-methoxy-propoxy)-propanoate] acid (ADONA) and chlorinated polyfluorinated ethersulfonic acids (6:2 and 8:2 Cl-PFESA) were detected in the particle phase, indicating that the use of PFAS alternatives gradually increases. The lgKd of PFASs between the water and particle phase ranges from 2.95±0.553 (PFPeA) to 3.85±0.237 (8:2 FTUCA)and the adsorption of fluorotelomer carboxylic acids (FTCAs) and fluorotelomer unsaturated carboxylic acids (FTUCAs) on particulate matter increases with increasing of carbon chain length. Perfluoroalkane sulfonic acids (PFSAs) are more easily adsorbed by particulate matter than perfluoroalkyl carboxylic acids (PFCAs). The fluxes of PFASs in the Weinan-Zhengzhou section of the Yellow River show a decrease at first and then increase, indicating that this section receives pollution inputs from the upstream and tributaries. In addition, the results show that the fluxes of PFASs in the water phase are greater than those in the particle phase.
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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-1 and ND to 1.30 mg·kg-1, respectively. Overall, the concentrations of heavy metals and PAHs increased with a decrease in dust particle size. In terms of composition, the heavy metals were dominated by Zn while the high-molecular-weight PAHs were mainly homologous. In spatial distribution, the concentrations of heavy metals and PAHs were different. The total concentrations of heavy metals in road dust near Renmin Road, Xiaodian Industrial Park, and Cement Plant were the highest, while the high concentrations of PAHs appeared in the dust of Renmin Road, Upper Expressway, and 107 National Highway. Pearson correlation analysis showed that there was no positive correlation between the five heavy metals and fifteen PAHs. Then cluster analysis and factor analysis indicated that the PAHs were greatly affected by vehicle emissions, while the heavy metals were basically unaffected.
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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 syn-DP, anti-DP, TBPH, PBEB, HBB, TBE, TBB, and DBDPE, were measured. The mean ∑NHFR concentration was significantly higher in Guangzhou (335 pg·m-3) than in Wuzhishan (90.6 pg·m-3). DBDPE was the most abundant component in Guangzhou, accounting for 66.9% of the ∑NHFR concentration, while TBPH was the major component (65.8%) in Wuzhishan. This indicates different pollution characteristics in Guangzhou and Wuzhishan. In addition, ∑NHFR concentration presented distinct seasonal variations only in Guangzhou, which could result from the different sources of origin of NHFRs. Principle component analysis showed that the atmospheric NHFRs in Guangzhou and Wuzhishan could originate from different sources. In the light of the results of wind frequency and HYSPLIT model analysis, NHFRs seem to originate mainly from the emissions from surrounding areas, including from the inputs of e-waste recycling, industrial activities, and re-volatilization of consumer goods in Guangzhou, while NHFRs mainly seem to originate from the movement of air mass over the Pearl River Delta and the seas in Wuzhishan. Meanwhile, several NHFRs presented different loading patterns in Guangzhou and Wuzhishan, and the emissions from different sources and commercial products could be the impactors. With detection of high NHFR concentrations in the atmosphere of Guangzhou, the long-time exposure of the surrounding residents (especially infants) is suspected to cause potential health risk.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Retardadores de Llama/análisis , Éteres Difenilos Halogenados/análisis , Atmósfera , China , Contaminación Ambiental , HumanosRESUMEN
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⻳] 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.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Éteres Difenilos Halogenados/análisis , Beijing , China , Ciudades , Humanos , Exposición por Inhalación , Bifenilos PolibrominadosRESUMEN
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.
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Polvo/análisis , Monitoreo del Ambiente , Contaminación Ambiental/análisis , Metales Pesados/análisis , Tamaño de la Partícula , Estaciones del Año , Beijing , China , Humanos , Medición de RiesgoRESUMEN
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.