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[Display omitted] • Hydrophobicity of [Bmim] 2 [CuCl 4 ] was reported. • Hygroscopic process of [Bmim] 2 [CuCl 4 ] was monitored in situ by time-dependent IR. • Hydrogen bond in [Bmim] 2 [CuCl 4 ] was analyzed by IR bands position shift. • Water molecules aggregation states in [Bmim] 2 [CuCl 4 ] was discussed. By dissolving copper chloride in [Bmim]Cl (1-butyl-3-methylimidazolium chloride), chloride ions can coordinate with copper ions and form [CuCl 4 ]2−, thereby inducing the solution being hydrophobic. In the present work, hydrogen bonds between [Bmim]+ and anions are analyzed and discussed by two-dimensional correlation spectroscopy. Time-dependent attenuated total reflection spectroscopy (ATR-FTIR) is introduced to monitor the hygroscopic process of [Bmim] 2 [CuCl 4 ] and [Bmim]Cl in situ. Hygroscopic capacity and rate of [Bmim] 2 [CuCl 4 ] shrink compared with [Bmim]Cl. The change of water molecular clusters has been studied by second-derivative spectra in the hygroscopic process. The behaviors of water molecular in the two ionic liquids are also distinctive. [ABSTRACT FROM AUTHOR]

Novel hollow molecularly imprinted polymer (HMIPs) microspheres were synthesized via two-stage dispersion polymerization and swelling seed polymerization technique with nicotinamide (NAM) as the template molecule. Binding experiments showed that the HMIPs possessed excellent binding properties toward N-nitroamines, including fast mass transfer rate, and efficient adsorption performance with the adsorption capacity reaching up to 1.7 mg/g, which was 3 times higher than that of hollow non-imprinted polymers (HNIPs). The fast binding kinetics for one N-nitrosamine (4-(methylnitrosamino)-1-(3-pyridine)-1-butanone, NNK) was attributed to the hollow porous structure with the imprinted cavities on both external and internal surface of the HMIPs. [ABSTRACT FROM AUTHOR]

In order to enhance Ni-EDTA decomplexation and Ni recovery via photoelectrocatalytic (PEC) process, TiO 2 /Ni-Sb-SnO 2 bifunctional electrode was fabricated as the photoanode and activated carbon fiber (ACF) was introduced as the cathode. At a cell voltage of 3.5 V and initial solution pH of 6.3, the TiO 2 /Ni-Sb-SnO 2 bifunctional photoanode exhibited a synergetic effect on the decomplexation of Ni-EDTA with the pseudo-first-order rate constant of 0.01068 min−1 with 180 min by using stainless steel (SS) cathode, which was 1.5 and 2.4 times higher than that of TiO 2 photoanode and Ni-Sb-SnO 2 anode, respectively. Moreover, both the efficiencies of Ni-EDTA decomplexation and Ni recovery were improved to 98% from 86% and 73% from 41% after replacing SS cathode with ACF cathode, respectively. Influencing factors on Ni-EDTA decomplexation and Ni recovery were investigated and the efficiencies were favored at acidic condition, higher cell voltage and lower initial Ni-EDTA concentration. Ni-EDTA was mainly decomposed via ·OH radicals which generated via the interaction of O 3 , H 2 O 2 , and UV irradiation in the contrasted PEC system. Then, the liberated Ni2+ ions which liberated from Ni-EDTA decomplexation were eventually reduced to metallic Ni on the ACF cathode surface. Finally, the stability of the constructed PEC system on Ni-EDTA decomplexation and Ni recovery was exhibited. [Display omitted] [ABSTRACT FROM AUTHOR]

Schematic plot of the attacking process of ROS and ACS to E.coli. [Display omitted] • ACS outperformed ROS on the inactivation of E.coli. • O 2 – conceived higher inactivation rate of E.coli than OH. • The membrane was broken firstly, and then inactivated by disinfectant. • Total protein would be the attacking point for ROS rather than RCS. Comprehensive study on the roles of reactive oxygen species (ROS) and active chlorine species (ACS) on the failure of bacteria cell were crucial for the development of electrochemical oxidation disinfection. Pure Na 2 SO 4 and chloride-containing solution were used to generate ROS and ACS, separately. When 14.4 mA/cm2 current density was applied, 5 logs reduction of E.coli was achieved with 60 min treatment in pure Na 2 SO 4 solution, while in the chloride-containing solution, E.coli was completely inactivated in 15 min as the initial concentration was about 7.5 logs. Cell membrane damage is a crucial step in electrochemical oxidation disinfection process. With 3.6 mA/cm2, there were ∼ 1.1 logs cells injured and it was about 37 times to that of inactivated cells with 5 min treatment in pure Na 2 SO 4 solution. Hydroxyl radical and superoxide radical were confirmed responsible for the inactivation of E.coli in pure Na 2 SO 4 electrolyte, while hypochlorite was dominated in chloride-containing solution. Noticeable shrinkages, wrinkles, and indentations were observed on the cell surfaces after treatment without any differences for ROS and ACS. However, total protein would be the attacking point for ROS rather than ACS. The changes of Optical density, total organic carbon, and potassium ions leakage presented slight differences. Nucleic acid matters may be destroyed in the electrochemical disinfection process, while the damage on nucleic acid fragment need more research to reveal. [ABSTRACT FROM AUTHOR]

• A portable NIRS quantification of 6-gingerol in ginger powder was developed. • Real ginger powder from different geographical origins were modeled and recognized. • NIRS analysis of ginger can be considered not just in lab but also at casual inspection. Ginger powder is an important spice that is susceptible to improper sales such as adulteration or geographical fraud. In this study, a portable near infrared spectroscopy was used to quantitatively predict the 6-gingerol content, an important quality index of ginger, as well as to identify the gingers from three origins in China. Specifically, the optimal preprocessing method was first investigated by comparing the predictions of models. Then three feature variable selection methods including PCA, CARS, and RFrog, on the quantitative analysis of 6-gingerol were also compared, respectively. After comparison, the PLS model established on the S-G combined with SNV preprocessing outperformed the others. The PLS regression of 6-gingerol with variables selected by RFrog possessed the R c 2 of 0.9463, R p 2 of 0.9497, and the RPD of 4.2257, respectively. Moreover, the results further verified that the LDA model by SPA variables extraction successfully identify gingers from different origins with 100 % accuracy. [ABSTRACT FROM AUTHOR]

The carbon nanotubes (CNTs) have been combined with graphitic carbon nitride (g-C 3 N 4 ) through the amidation reaction. The hybrid catalyst of g-C 3 N 4 -CNTs with well-defined and stable structure exhibits efficient catalytic performance (32.6 μmol h −1 ) for photocatalytic H 2 O 2 production in the presence of formic acid under visible light. The value of electron transfer during the oxygen reduction reaction (ORR) process obtained from the Koutecky-Levich plot for g-C 3 N 4 -CNTs (n = 1.96) is higher than that for g-C 3 N 4 (n = 1.29), suggesting that the CNTs covalent combined with g-C 3 N 4 can promote the electrons generation. The p -benzoquinone (PBQ) scavenger experiments, the electron spin resonance (ESR) signal and quantitative experiment of O 2 − results reveal that the negative shifts of the conduction band (CB) level from g-C 3 N 4 to g-C 3 N 4 -CNTs can enhance the single-electron reduction of O 2 to O 2 − and further promote the sequential two-step single-electron O 2 reduction reaction to H 2 O 2 . [ABSTRACT FROM AUTHOR]

Tobacco-specific N -nitrosamines (TSNAs) are strong carcinogens widely found in tobacco products, environmental tobacco smoke, lake, and wastewater. The main objective of this study was to investigate the effects of cigarette smoke with different yields of TSNAs (NNK, NNN, NAT, NAB) and nicotine on the levels of biomarkers of exposure in smokers' plasma. Three hundred healthy volunteers were recruited comprising 60 smokers of each of 3 mg, 8 mg and 10 mg ISO tar yield cigarettes and 60 smokers who smoked 10 mg, 8 mg, and 3 mg for 14 days sequentially and 60 non-smokers. All study participants were male, aged from 21 to 45 years old, and were recruited from a same unit in Hebei, China. We measured the levels of NNAL, NAT, NNN, NAB and cotinine in plasma from 240 smokers and 60 non-smokers using a novel method established by online two-dimensional solid phase extraction-liquid chromatography-tandem mass spectrometry. The results showed that NNAL, NAT, NNN, NAB and cotinine in the plasma of smokers smoking cigarette with low TSNAs and nicotine were lower than that with high TSNAs and nicotine. When smokers switched from higher to lower TSNA yields of cigarettes, their plasma NNAL, NAT, NNN, NAB levels significantly decreased. The plasma concentrations of NNAL were significantly correlated with those of cotinine, NNN, NAT and NAB for smokers (p < 0.001). Similarly, the plasma concentrations of cotinine were significantly correlated with those of NNN, NAT and NAB for smokers (p < 0.001). The plasma NNAL, NAT, NNN, NAB and cotinine levels for smokers were significantly higher than those for non-smokers. These findings suggested that the total NNAL, NNN, NAT, NAB and cotinine in plasma were valid and reliable biomarkers for human exposure to TSNAs and nicotine. • The plasma levels of TSNAs in smokers and non-smokers were measured. • The variations of plasma TSNAs of smokers after switching were investigated. • The reductions in smoke TSNA yields can reduce mean biomarkers of exposure levels. • TSNAs and nicotine metabolite biomarkers in plasma were highly correlated. • The plasma TSNA were valid and reliable biomarkers of human exposure to TSNAs. [ABSTRACT FROM AUTHOR]

Tobacco-specific N -nitrosamines (TSNAs) are strong carcinogens widely found in tobacco products, environmental tobacco smoke, lake, and wastewater. The main objective of this study was to investigate the effects of cigarette smoke with different yields of TSNAs (NNK, NNN, NAT, NAB) and nicotine on the levels of biomarkers of exposure in smokers' plasma. Three hundred healthy volunteers were recruited comprising 60 smokers of each of 3 mg, 8 mg and 10 mg ISO tar yield cigarettes and 60 smokers who smoked 10 mg, 8 mg, and 3 mg for 14 days sequentially and 60 non-smokers. All study participants were male, aged from 21 to 45 years old, and were recruited from a same unit in Hebei, China. We measured the levels of NNAL, NAT, NNN, NAB and cotinine in plasma from 240 smokers and 60 non-smokers using a novel method established by online two-dimensional solid phase extraction-liquid chromatography-tandem mass spectrometry. The results showed that NNAL, NAT, NNN, NAB and cotinine in the plasma of smokers smoking cigarette with low TSNAs and nicotine were lower than that with high TSNAs and nicotine. When smokers switched from higher to lower TSNA yields of cigarettes, their plasma NNAL, NAT, NNN, NAB levels significantly decreased. The plasma concentrations of NNAL were significantly correlated with those of cotinine, NNN, NAT and NAB for smokers (p < 0.001). Similarly, the plasma concentrations of cotinine were significantly correlated with those of NNN, NAT and NAB for smokers (p < 0.001). The plasma NNAL, NAT, NNN, NAB and cotinine levels for smokers were significantly higher than those for non-smokers. These findings suggested that the total NNAL, NNN, NAT, NAB and cotinine in plasma were valid and reliable biomarkers for human exposure to TSNAs and nicotine. • The plasma levels of TSNAs in smokers and non-smokers were measured. • The variations of plasma TSNAs of smokers after switching were investigated. • The reductions in smoke TSNA yields can reduce mean biomarkers of exposure levels. • TSNAs and nicotine metabolite biomarkers in plasma were highly correlated. • The plasma TSNA were valid and reliable biomarkers of human exposure to TSNAs. [ABSTRACT FROM AUTHOR]