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A new four-dimensional (4D)ab initiopotential energy surface (PES) for Ne–CS2involving theQ1andQ3normal modes for the ν1symmetric stretching vibration and ν3antisymmetric stretching vibration of CS2is presented. The PES is constructed at the coupled-cluster singles and doubles with noniterative inclusion of connected triples [CCSD(T)]-F12 level with a large basis set including midpoint bond functions. Two vibrationally averaged potentials with CS2at the vibrational ground and ν1+ ν3excited states are generated from the 4D potential. Each potential contains a T-shaped global minimum and two equivalent linear local minima. The rovibrational energy levels and bound states are calculated employing radial discrete variable representation/angular finite basis representation and the Lanczos algorithm. In addition, the predicted band origin shift is 0.2514 cm−1for Ne–CS2. The spectroscopic parameters are also predicted. [ABSTRACT FROM AUTHOR]

To investigate the effect of black carbon (BC) particles on complement activation in human corneal epithelial cells (HCECs) and determine whether this effect can be attenuated by inhibiting the NLPR3 inflammasome pathway. HCECs were treated with fresh BC (FBC) or ozone-oxidized BC (OBC) particles at a concentration of 200 μg/ml for 72 hours. Complement activation was observed by detecting C5b-9 protein level in cell culture supernatant using ELISA. HCECs were transfected with duplexes of siRNA targeting NLRP3 (NLRP3-siRNA) at 0.1 pmol/µl for 24 hours to inhibit the NLPR3 inflammasome pathway. RT-qPCR was performed to examine the efficacy of NLRP3-siRNA for inhibition; a random siRNA duplex was used for control siRNA. Both FBC exposure and OBC exposure for 72 hours significantly increased the C5b-9 protein level compared to negative control cells (all P <.05). However, the difference in C5b-9 level after FBC exposure and OBC exposure was not statistically significant (P >.05). NLRP3-siRNA transfection reduced C5b-9 protein levels in FBC-treated and OBC-treated HCECs compared to control (lowered by 27% in the FBC-treated group and by 23% in the OBC-treated group, all P <.05). BC particles, including FBC and OBC, triggered complement activation, increasing the protein level of C5b-9 in cultured HCECs. siRNA targeting NLRP3 to inhibit NLRP3 generation reduced C5b-9 protein level in HCECs treated with FBC or OBC particles, indicating that BC induces complement activation potentially through the NLRP3 inflammasome in HCECs. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have been extensively investigated since the exfoliation of graphene. Due to the excellent and versatile properties, the promising applications in novel nanodevices have been proposed in the last few years. Here, we chose three stable 2D materials which have been experimentally synthesized and have potential to be used for next-generation nanodevices, namely semiconducting MoS2, Janus MoSSe, and magnetic CrI3, to review their electronic/magnetic properties, and reveal the relationship of the properties-applications in devices. The showcase review on property-application is expected to provide new research insights into the investigations of 2D materials. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the cytotoxic effects of fresh black carbon (FBC) particles and ozone-oxidized BC (OBC) particles on human corneal epithelial cells (HCECs), and the role of the NLRP3 inflammasome signal pathway in the process. Methods: HCECs were treated with different doses of FBC and OBC particles, the cell inhibitory effect was observed by MTS assay and the inhibitory concentration 50 (IC50) was calculated; the effect of FBC and OBC particles on cell apoptosis was assessed using flow cytometry-based annexin V/7AAD assay; the mRNA levels of NLRP3 inflammasome signal pathway components (NLRP3, ASC, and Caspase-1) and downstream cytokine (IL-1 β) were detected in HCECs. Results: After treatment for 24 h, the IC50 of FBC and OBC particles in HCECs were 295.5 μg/ml and 224.6 μg/ml, respectively. The percentages of cells in total apoptosis after exposure to FBC and OBC were significantly higher than in untreated control cells (P <.001). Moreover, OBC exposed cells exhibited significantly more total apoptosis than FBC exposed cells (P <.001). Compared to the untreated control, there was enhanced mRNA expression of NLRP3, Caspased-1, ASC, and IL-1β in both FBC and OBC treated HCECs (all P <.01). In addition, OBC treated HCECs yielded higher levels of IL-1β mRNA compared to FBC treated cells (P <.05). Conclusion: Both FBC and OBC particles have a cytotoxic effect on HCECs, accompanied by NLRP3 inflammasome activation, indicating that the NLRP3 inflammasome signaling pathway may be involved in the pathogenesis of the BC cytotoxic process. OBC is more toxic than FBC particles. [ABSTRACT FROM AUTHOR]

Reaction of 1,1′-bis(diphenylphosphino)ferrocene (dppf) with [μ-(SCH2)2NCH2CH2OH]Fe2(CO)6(A) or [μ-(SCH2)2NCH2CH2SAc]Fe2(CO)6(C) in refluxing xylene yielded an intramolecular bridging complex [μ-(SCH2)2NCH2CH2OH]Fe2(CO)4(μ-dppf) (1) or [μ-(SCH2)2NCH2CH2SAc]Fe2(CO)4(μ-dppf) (2) in moderate yield. The structures of both complexes were fully characterized by spectroscopic methods and X-ray crystallography, and the electronic structure of2was further investigated by UV–vis. The cyclic voltammetry was conducted and the reduction of protons from CF3SO3H (TfOH), HBF4·Et2O, or CF3COOH (TFA) catalyzed by2was observed. [ABSTRACT FROM AUTHOR]

Low-Cost Sensors (LCS) of fine particulate matter (PM2.5) have been widely used to supplement regular air quality monitoring stations. However, the sensor output is impacted by environmental factors, especially relative humidity, and must be calibrated to yield estimates of concentrations. In this study, we evaluate the performance of a linear model and a generalized additive model (GAM) to calibrate the output of LCS PM2.5 measurements in terms of different relative humidity levels. The method is based on co-located measurements from an LCS and a conventional reference monitor at two sites in an urban area in northern China. A stepwise variable selection of air pollutant concentrations and meteorological observations is used to select inputs to the model in order to improve the calibration ability. The results show that when relative humidity is below 75%, linear calibration of LCS PM2.5 observations can output PM2.5 mass concentrations close to the reference method with a correlation coefficient (R2) of 0.86. When relative humidity is above 75%, the GAM calibration model significantly outperforms the linear model, with an R2 of approximately 0.83. Overall, the linear model exhibits good fitness in dry conditions, while the GAM captures PM2.5 variations best in humid conditions. We conclude that low-cost PM2.5 sensors are sensitive to relative humidity and that therefore condition-specific calibration methods need to be used to improve the quality of the data as well as to improve the match with reference measurements. Copyright © 2021 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Reaction of precursor Fe2[(μ-SeCH2)2CHC6H5](CO)6 (A) with 1,3-bis(diphenylphosphine)propane (dppp) in refluxing xylene yielded one diphosphine-containing complex Fe2[(μ-SeCH2)2CHC6H5](CO)4(κ2-dppp) (1) with the diphosphine of dppp displacing the apical and one basal carbonyl ligands of a single iron center, while treatment of precursor A with one-half equivalent of dppp in MeCN in the presence of Me3NO·2H2O gave another diphosphine-containing complex {Fe2[(μ-SeCH2)2CHC6H5](CO)5}2(μ,κ1,κ1-dppp) (2) with the diphosphine of the dppp bridging two diiron diselenolato clusters upon replacing one of basal carbonyls, respectively. The structures of both complexes were fully characterized by spectroscopic methods and X-ray crystallography. The electrochemical behaviors of both complexes were investigated by cyclic voltammetry (CV) and the electrochemical reduction of protons from acetic acid to give dihydrogen catalyzed by complex Fe2[(μ-SeCH2)2CHC6H5](CO)4(κ2-dppp) was observed. [ABSTRACT FROM AUTHOR]

Reactions of [(μ-SeCH2)2CHC6H5]Fe2(CO)6 (A) with 1,1′-bis(diphenylphosphino)ferrocene (dppf) or 1,3-bis(diphenylphosphino)propane (dppp) in refluxing xylene yielded [(μ-SeCH2)2CHC6H5]Fe2(CO)4(μ-dppf) (1) or [(μ-SeCH2)2CHC6H5]Fe2(CO)4(μ-dppp) (2) in moderate yields. The chemical structures of both complexes were characterized by spectroscopic methods and X-ray crystallography, and the electronic structures were further investigated by UV–vis. The redox properties of both complexes in the absence and presence of acetic acid were observed by cyclic voltammetry (CV). [ABSTRACT FROM AUTHOR]

Reaction of 1,2-bis(diphenylphosphino)benzene (dppbz) with PhpdtFe2(CO)6 (A) in hot acetonitrile yielded a chelated complex, PhpdtFe2(CO)4(κ2-dppbz) (1), in moderate yield. Further treatment using an excess of HBF4·Et2O resulted in the protonation of 1 at room temperature in dichloromethane solution, forming a hydride [Phpdt(μ-H)Fe2(CO)4(κ2-dppbz)]BF4 (2). The chemical structures of both complexes were fully characterized by spectroscopic methods and X-ray crystallography, and the electronic structures were further investigated by UV-vis spectroscopy. The cyclic voltammetry (CV) of 1 in the absence and presence of acetic acid were also investigated. [ABSTRACT FROM AUTHOR]

A number of literatures have documented adverse health effects of exposure to fine particulate matter (PM2.5), and secondary sulfate aerosol and black carbon may contribute to health impacts of PM2.5exposure. We designed an exposure system to generate sulfate and traffic soot particles, and assessed the feasibility of using it for human exposure assessment in a pilot human exposure study. In the designed exposure system, average mass concentrations of generated sulfate and soot particles were 74.19μg/m3and 11.54μg/m3in the chamber and did not vary significantly during two-hour human exposure sessions. The size ranges of generated sulfate were largely between 20 to 200 nm, whereas those of generated soot particles were in the size ranges of 50 to 200nm. Following two-hour exposure to generated sulfate and soot particles, we observed significant increases in fractional exhaled NO (FeNO) in young and health subjects. Building on established human exposure system and health response follow-up methods, future full-scale studies focusing on the effects of mixed particulates and individual PM2.5components would provide data in understanding the underpinning cardio-respiratory outcomes in relation to air pollution mixture exposure. Implications: Controlled exposure is a useful design to measure the biological responses repeatedly following particulate exposures of target components and set exposure at target levels of health concerns. Our study provides rational and establishes method for future full-scale studies to focus on examining the effects of mixed particulates and individual PM2.5components. [ABSTRACT FROM PUBLISHER]

Treatment of diiron dithiolate complex, [(μ-SCH2)2CHC6H5]Fe2(CO)6(A), with one equivalent of bidentate phosphine-containing ligandN,N-bis(diphenylphosphine)butanamine [(Ph2P)2N-Bu-n] in refluxing xylene afforded the diphosphine-bridged complex [(μ-SCH2)2CHC6H5]Fe2(CO)4[(μ-PPh2)2N-Bu-n] (1) in high yield, while reaction ofAwith two equivalents of triphenylphosphine (PPh3) in the presence of decarbonylating agent Me3NO yielded the disubstituted complex [(μ-SCH2)2CHC6H5]Fe2(CO)4(PPh3)2(2) in low yield. Both complexes were characterized by spectroscopic methods and X-ray crystallography. In the solid state, two phosphines of (PPh2)2N-Bu-n bridge the two irons withcisbasal-basal conformation, while PPh3occupies an apical position of the square pyramidal geometries of each iron. The influence of coordination manner on the electrochemical properties of both complexes was investigated by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Reaction of the diiron propanedithiolate complex [μ-(SCH2)2CHO2CC6H5]Fe2(CO)6(A) with triphenylphosphine (PPh3) orcis-1,2-bis(diphenylphosphine)ethylene (cis-dppv) in the presence of one equivalent of Me3NO·2H2O yielded a mono-substituted complex [μ-(SCH2)2CHO2CC6H5]Fe2(CO)5(PPh3) (1) or an asymmetrically substituted complex [(μ-SCH2)2CHO2CC6H5]Fe2(CO)4(κ2-dppv) (2), respectively. The structures of both complexes were characterized by spectroscopic methods and X-ray crystallography. In the solid state, the PPh3ligand in1occupies an apical position of the square pyramidal geometries of the Fe2, while thecis-dppv in2coordinates Fe2 in an apical-basal manner. The electrochemistry of both complexes was investigated. The electron-withdrawing benzoate functionality on the bridgehead carbon of the propanedithiolate bridge shifts the oxidation and reduction potentials of1or2slightly. Both complexes can catalyze the reduction of protons from CF3COOH but with a higher efficiency for2. [ABSTRACT FROM AUTHOR]

A new binuclear zinc complex, namely [Zn(Salpn)4(1,3-btp)]n(1, H2salpn = N,N′- bis(salicylidene)-1,3-diaminopropane, while 1,3- btp = 1,3-bis (triazole) propane) has been synthesized under one-pot reaction conditions in high yield, and has been characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction. The complex 1 crystallizes in the monoclinic system, space group ofC2/cwitha= 18.2270(17),b= 10.7435(10),c= 20.2896(19) Å,β= 92.9780(10)°. The two adjacent zinc-Salpn moieties were connected through the flexible 1,3-btp ligand into a binuclear unit. The bulk purity of the materials of 1 was confirmed through the powder X-ray diffraction (PXRD) experiments. Furthermore, the luminescent property of the complex 1 has also been investigated. Supplemental materials are available for this article. Go to the publisher's online edition ofSynthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistryto view the supplemental file. [ABSTRACT FROM AUTHOR]

In this work, a chloro-bridged trinuclear copper complex {[Cu(bpea)Cl]2CuCl4} (1) (bpea = N,N-bis(2-pyridylmethyl)ethylamine) has been synthesized and structurally characterized. In 1, two mononuclear [Cu(bpea)Cl]+ are linked by one [image omitted], generating a sandwich-like trinuclear unit. A crystallographic C2 axis passes through the Cu of the connecting [image omitted]. Susceptibility data of 1 indicate weak intratrimer ferromagnetic coupling with J = 5.16 cm-1. Elemental analysis, infrared, UV spectra, and electrochemistry of the complex were also determined. [ABSTRACT FROM AUTHOR]