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Air traffic is rapidly growing, raising concerns about the air pollution in the surroundings of airports and its impact on public health. However, little is known about the impact of air pollution sources on air quality and health in the vicinity of airports. In this study, the sources and adverse health effects of airport-related particulate matter (PM) were investigated and compared to those of urban traffic emissions. Ambient PM 0.25 were collected at the Los Angeles International Airport (LAX) and at a central Los Angeles site (USC campus), along with PM 2.5 collected directly from turbine and diesel engines. The particle chemical composition, oxidative potential (OP) (ascorbic acid (AA), and electron spin resonance (ESR) assay) as well as their reactive oxygen species (ROS) activity, inflammatory potential (interleukin (IL) 6 and 8 and tumor necrosis factor (TNF)–α) and cytotoxicity on human bronchial epithelial (16HBE) cells were assessed. Chemical composition measurements confirmed that aircraft emissions were the major source to LAX PM 0.25 , while the sources of the USC samples were more complex, including traffic emissions, suspended road and soil dust, and secondary aerosols. The traffic-related transition metals (Fe and Cu) in LAX and USC samples mainly affected OP values of particles, while multiple factors such as composition, size distribution and internalized amount of particles contributed to the promotion of ROS generation in 16HBE cells during 4 h exposure. Internalized particles in cells might also play an important role in activating inflammatory responses during cell recovery period, with LAX particles being more potent. Our results demonstrated considerable toxicity of airport-related particles, even at low exposure concentrations, suggesting that airport emission as source of PM 0.25 may also contribute to the adverse effects on public health attributable to PM. The potency of such particles is in the same range as those collected at a site in urban area impacted heavily by traffic emissions. [ABSTRACT FROM AUTHOR]

The effect of dust particle size on the distribution and bioaccessibility of flame retardants (FRs) in indoor dust remains unclear. In this study, we analyzed 20 FRs (including 6 organophosphate flame retardants (OPFRs), 8 polybrominated diphenyl ethers (PBDEs), 4 novel brominated flame retardants (NBFRs), and 2 dechlorane plus (DPs)) in composite dust samples from offices, public microenvironments (PME), and cars in Nanjing, China. Each composite sample (one per microenvironment) was separated into 6 size fractions (F1–F6: 200–2000 µm, 150–200 µm, 100–150 µm, 63–100 µm, 43–63 µm, and <43 µm). FRs concentrations were the highest in car dust, being 16 and 6 times higher than those in offices and PME. The distribution of FRs in different size fractions was Kow-dependent and affected by surface area (Log Kow=1–4), total organic carbon (Log Kow=4–9), and FR migration pathways into dust (Log Kow>9). Bioaccessibility of FRs was measured by the physiologically-based extraction test, with OPFR bioaccessibility being 1.8–82% while bioaccessible PBDEs, NBFRs, and DPs were under detection limits due to their high hydrophobicity. The OPFR bioaccessibility in 200–2000 µm fraction was significantly higher than that of <43 µm fraction, but with no difference among the other four fractions. Risk assessment was performed for the most abundant OPFR-tris(2-chloroethyl) phosphate. The average daily dose (ADD) values were the highest for the <43 µm fraction for all three types of dust using total concentrations, but no consistent trend was found among the three types of dust if based on bioaccessible concentrations. Our results indicated that dust size impacted human exposure estimation of FRs due to their variability in distribution and bioaccessibility among different fractions. For future risk assessment, size selection for dust sampling should be standardized and bioaccessibility of FRs should not be overlooked. [ABSTRACT FROM AUTHOR]

Cancerous human liver cell line has been used to test the hepatic toxicity of indoor dust, showing its organic extract decreases cell viability. However, little is known about its impact on normal human liver cell line. In the present study, we compared the cellular responses between carcinoma cell line (HepG2) and normal cell line (HL-7702) after exposing to 10–640 μg/100 μL organic dust extract for 24 h. The dust extract caused cytotoxicity, oxidative damage, inflammatory response and loss of mitochondrial transmembrane potential (MMP) in both cells. The inhibition of cell viability in HL-7702 cells was stronger than that in HepG2 cells, with HL-7702 cells having lower LC 50 . Higher production of oxidative stress, more loss of MMP and stronger suppression of antioxidant enzymes mRNA level occurred in HepG2 cells, while mRNA expression and hepcidin secretion were enhanced in HL-7702 cells at 40/100 μL, indicating the dust extract probably perturbed their liver Fe homeostasis. Our data showed considerable differences in cellular responses between normal and cancerous cell lines. To obtain accurate data, normal hepatocytes should be employed as they better match with the in vivo tissue than cancerous cell lines. [ABSTRACT FROM AUTHOR]

Human cornea is highly susceptible to damage by dust. Continued daily exposure to housedust has been associated with increasing risks of corneal injury, however, the underlying mechanism has not been elucidated. In this study, a composite housedust sample was tested for its cytotoxicity on primary human corneal epithelial (PHCE) cells, which were exposed to dust at 5–320 μg/100 μL for 24 h. PHCE cell viability showed a concentration-dependent toxic effect, attributing to elevated intracellular ROS. Moreover, when exposed at > 20–80 μg/100 μL, dust-induced oxidative damage was evidenced by increased malondialdehyde and 8-hydroxy-2-deoxyguanosine (1.3–2.3-fold) and decreased antioxidative capacity (1.6–3.5-fold). Alteration of mRNA expression of antioxidant enzymes ( SOD1 , CAT , HO-1 , TRXR1 , GSTM1 , GSTP1 , and GPX1 ) and pro-inflammatory mediators ( IL-1β , IL-6 , IL-8 , TNF-α , and MCP-1 ) were also observed. Furthermore, the mitochondrial transmembrane potential was dissipated from 9.2 to 82%. Our results suggested that dust-induced oxidative stress probably played a vital role in the cytotoxicity in PHCE cells, which may have contributed to dust-induced impairment of human cornea. [ABSTRACT FROM AUTHOR]

[Display omitted] • "Mini-BACS + AES" setup can be used for in vitro hazard characterization of simulated fume events. • Aircraft hydraulic fluid fumes are more harmful than engine oil fumes. • Higher OP level and smaller particle size may contribute to higher toxicity of hydraulic fluid fumes. • Our results clearly reflect potential health risks associated with fume events in aircraft cabins. Contamination of aircraft cabin air can result from leakage of engine oils and hydraulic fluids into bleed air. This may cause adverse health effects in cabin crews and passengers. To realistically mimic inhalation exposure to aircraft cabin bleed-air contaminants, a mini bleed-air contaminants simulator (Mini-BACS) was constructed and connected to an air-liquid interface (ALI) aerosol exposure system (AES). This unique "Mini-BACS + AES" setup provides steady conditions to perform ALI exposure of the mono- and co-culture lung models to fumes from pyrolysis of aircraft engine oils and hydraulic fluids at respectively 200 °C and 350 °C. Meanwhile, physicochemical characteristics of test atmospheres were continuously monitored during the entire ALI exposure, including chemical composition, particle number concentration (PNC) and particles size distribution (PSD). Additional off-line chemical characterization was also performed for the generated fume. We started with submerged exposure to fumes generated from 4 types of engine oil (Fume A, B, C, and D) and 2 types of hydraulic fluid (Fume E and F). Following submerged exposures, Fume E and F as well as Fume A and B exerted the highest toxicity, which were therefore further tested under ALI exposure conditions. ALI exposures reveal that these selected engine oil (0–100 mg/m3) and hydraulic fluid (0–90 mg/m3) fumes at tested dose-ranges can impair epithelial barrier functions, induce cytotoxicity, produce pro-inflammatory responses, and reduce cell viability. Hydraulic fluid fumes are more toxic than engine oil fumes on the mass concentration basis. This may be related to higher abundance of organophosphates (OPs, ≈2800 µg/m3) and smaller particle size (≈50 nm) of hydraulic fluid fumes. Our results suggest that exposure to engine oil and hydraulic fluid fumes can induce considerable lung toxicity, clearly reflecting the potential health risks of contaminated aircraft cabin air. [ABSTRACT FROM AUTHOR]

Two couples of enantiomedcally pure chiral cyano-bridged heterobimetallic chain coordination polymers, [Mn((R,R)Salcy)Fe(Tp)(CN)3∙H2O∙1/2CH3CN]n (1), [Mn((S,S)-Salcy)Fe(Tp)(CN)3∙H2O—1/2CH3CN]n (2), [Mn((R,R)Salcy)Fe(bpca)(CN)3—H2O]n (3), and [Mn((S,-Salcy)Fe(bpca)(CN)3∙H2O]n (4) [(R,R)-Salcy or (S,S)-Salcy = (R,R)- or (S,S)-N,N'-(1,2-cyclohexanediylethylene)bis(salicylideneiminato) dianion, Tp = tris(pyrazofyl)hydroborate, bpca = bis(2-pyddylcarbonyl)amidate anion], were synthesized using the mod8ied cyanometalate building blocks [Fe(L)(CN)3]- (L = Tp, bpca) and the chiral polydentate Schiff base manganese(lll) complex fragments. The circular dictiroism measurements showed Cotton effects of the opposite sign at the same wavelength for each pair of enantiomers. Magnetic property studies indicated that complexes 1 and 2 show not only intrachain but also interchain field-induced metamagnetic transitions from an antiferromagnetic to a ferromagnetic state and exhibit an antiferromagnetic tong-range ordering with a TN of 3.2 K, while enantiomers 3 and 4 are typical antiferromagnetic coupling compounds. Furthermore, complex 3 exhibits a ferroetectric behavior that relates to the polar point group C2, in which it crystallizes. [ABSTRACT FROM AUTHOR]

In the title compound, C6H7N3O2·H2O, all atoms of 2-ureidopyridine N-oxide molecule are approximately coplanar and adjacent molecules are connected by strong hydrogen bonds, resulting in a three-dimensional network. [ABSTRACT FROM AUTHOR]

The title complex, [Cu(C7H2N2O7)(C4H8N2O2)(H2O)], is a mononuclear copper(II) compound. The CuII ion is five-coordinated in a distorted pyramidal geometry by two N atoms from one dimethylglyoxime molecule, two O atoms from one 3,5-dinitro-2-oxidobenzoate ligand and one O atom from a water molecule. Strong hydrogen bonds connect adjacent molecules into a three-dimensional network. [ABSTRACT FROM AUTHOR]

With the use of the tailored cyanometalate precursor, (Bu4N)[(Tp)Fe(CN)3] (Tp = Tris(pyrazolyl)hydroborate) as the building block to react with fully solvated CuII, CoII, and NiII cations, four one-dimensional (1D) heterobimetallic cyano-bridged chain complexes of squares, [(Tp)2FeII2(CN)6Cu(CH3OH)·2CH3OH]n (1), [(Tp)2FeII2(CN)6Cu(DMF)·DMF]n (2), [(Tp)2FeIII2(CN)6M(CH3OH)2·2CH3OH]n (M = Co (3) and Ni (4)), have been prepared. In complexes 1 and 2, the CuII ions are pentacoordinated in the form of a slightly distorted square-based pyramid, and they are linked by distorted octahedrons of [(Tp)Fe(CN)3]- to form 1D chains of squares. In complexes 3 and 4, both the central CoII and NiII ions have a slightly distorted octahedral coordination geometry, and they are bridged by [(Tp)Fe(CN)3]- to form similar 1D chains of squares. There are weak interchain π-π stacking interactions through the pyrazolyl groups of the Tp ligands for complexes 3 and 4. The crystal structures and magnetic studies demonstrate that complexes 1 and 2 exhibit intrachain ferromagnetic coupling and single-chain magnets behavior, and the blocking temperature is ca. 6 K for complex 1 and ca. 3 K for complex 2. Complexes 3 and 4 show significant metamagnetic behavior, where the cyanides mediate the intrachain ferromagnetic coupling between FeIII and CoII or NiII ions and the interchain π-π stacking interactions lead to antiferromagnetic couplings. The field dependence of the magnetization measurements shows that the critical field is around 1 kOe for complex 3 and 0.8 kOe for complex 4 at 1.8 K. [ABSTRACT FROM AUTHOR]

Two new cyano-bridged one-dimensional heterobimetallic coordination polymers, [(bpca)2FeIII2(CN)6Cu(H2O)2·1.5H2O]n (2) and [(bpca)FeIII(CN)3Cu(bpca)(H2O)·H2O]n (3), and a trinuclear complex, [(bpca)2FeIII2(CN)6Mn(CH3OH)2(H2O)2]·2H2O (4), have been synthesized using the tailored tricyanometalate precursor (Bu4N)[Fe(bpca)(CN)3]·H2O (1) (Bu4N+ = tetrabutylammonium cation; bpca = bis(2-pyridylcarbonyl)amidate anion) as a building block and structurally characterized. In complex 2, the CuII ions are six-coordinated in an elongated distorted octahedral environment, and they are linked by distorted octahedrons of [Fe(bpca)(CN)3]- to form 1D chain of squares. Complex 3 is an unexpected chiral heterobimetallic helical chain complex, in which the helical chain consists of the asymmetric unit of [(bpca)Fe(CN)3Cu(bpca)(H2O)]. In complex 4, there are two independent trinuclear clusters in one asymmetric unit, and the coordination modes of the two methanol and two water molecules coordinating to the central Mn(II) ion are different (cis and trans). Complex 2 shows metamagnetic behavior with a Neel temperature of TN = 2.2 K and a critical field of 250 Oe at 1.8 K, where the cyanides mediate the intrachain ferromagnetic coupling between the CuII and FeIII ions. Complex 3 shows ferromagnetic coupling between CuII and FeIII ions, the best-fit for χMT versus T using a 1D alternating chain model leads to the parameters J1 = 7.9(3) cm-1, J2 = 1.03(2) cm-1, and g = 2.196(3). Complex 4 exhibits ferrimagnetic behavior caused by the noncompensation of the local interacting spins (SMn = 5/2 and SFe = 1/2) which interact antiferromagnetically through bridging cyano groups. [ABSTRACT FROM AUTHOR]

Inhalation exposure to environmental and occupational aerosol contaminants is associated with many respiratory health problems. To realistically mimic long-term inhalation exposure for toxicity testing, lung epithelial cells need to maintained and exposed under air-liquid interface (ALI) conditions for a prolonged period of time. In addition, to study cellular responses to aerosol particles, lung epithelial cells have to be co-cultured with macrophages. To that aim, we evaluated human bronchial epithelial Calu-3, 16HBE14o- (16HBE), H292, and BEAS-2B cell lines with respect to epithelial morphology, barrier function and cell viability under prolonged ALI culture conditions. Only the Calu-3 cells can retain the monolayer structure and maintain a strong tight junction under long-term ALI culture at least up to 2 weeks. As such, Calu-3 cells were applied as the structural barrier to create co-culture models with human monocyte-derived macrophages (MDMs) and THP-1 derived macrophages (TDMs). Adhesion of macrophages onto the epithelial monolayer was allowed for 4 h with a density of 5 × 104 macrophages/cm2. In comparison to the Calu-3 mono-culture model, Calu-3 + TDM and Calu-3 + MDM co-culture models showed an increased sensitivity in inflammatory responses to lipopolysaccharide (LPS) aerosol at Day 1 of co-culture, with the Calu-3 + MDM model giving a stronger response than Calu-3 + TDM. Therefore, the epithelial monolayer integrity and increased sensitivity make the Calu-3 + MDM co-culture model a preferred option for ALI exposure to inhaled aerosols for toxicity testing. • Calu-3+MDM model shows the epithelial monolayer integrity under prolonged ALI culture. • Calu-3+MDM model has an increased sensitivity in inflammatory responses to LPS aerosol. • Combination of Calu-3+MDM model is a preferred option for long-term ALI exposure to inhaled aerosols. [ABSTRACT FROM AUTHOR]

Relatively high concentrations of ultrafine particles (UFPs) have been observed around airports, in which aviation and road traffic emissions are the major sources. This raises concerns about the potential health impacts of airport UFPs, particularly in comparison to those emitted by road traffic. UFPs mainly derived from aviation or road traffic emissions were collected from a location near a major international airport, Amsterdam-Schiphol airport (AMS), depending on the wind direction, along with UFPs from an aircraft turbine engine at low and full thrust. Human bronchial epithelial cells (Calu-3) model in combination with an air-liquid interface (ALI) cloud system was used for the in vitro exposure to UFPs at low doses ranging from 0.09 to 2.07 μg/cm2. Particle size distribution was measured. Cell viability, cytotoxicity and inflammatory potential (interleukin (IL) 6 and 8 secretion) on Calu-3 cells were assessed after exposure for 24 h. The biological measurements on Calu-3 cells confirm that pro-inflammatory responses still can be activated at the high cell viability (> 80%) and low cytotoxicity. By the Benchmark Dose (BMD) analysis, Airport and Non-Airport (road traffic) UFPs as well as UFPs samples from a turbine engine have similar toxic properties. Our results suggest that UFPs from aviation and road traffic in airport surroundings may have similar adverse effects on public health. • Airport and road traffic UFPs can activate inflammation in Calu-3 cells. • Airport UFPs exert similar toxicity compared to UFPs from road traffic emission. • ALI condition promotes cellular responses to particles at low exposed dose. [ABSTRACT FROM AUTHOR]

The construction of multifunctional metal-organic frameworks (MOFs) has attracted considerable attention. Two novel Dy-MOFs namely [Dy2(TPTC-2OMe)1.5(H2O)4·H2O]n (1) and {[Dy2(TPTC-2OMe)(H2TPTC-2OMe) (H2O)2]·2H2O}n (2) were obtained by a solvothermal method using 2′,5′-dimethoxy-[1,1′:4′,1″-terphenyl]- 4,4″-dicarboxylic acid (H4TPTC-2OMe) as the ligand. Structure analysis demonstrates that both MOFs 1 and 2 displayed three-dimensional framework structures, in which MOF 1 was with Dy(III) metal chains as nodes, while MOF 2 was with Dy2 binuclear metal clusters as nodes. Interestingly, MOFs 1 and 2 exhibited high thermal and chemistry stabilities and presented relatively high proton conductivity (σ) values of 1.69 × 10-4 S cm-1 and 3.52 × 10-6 S cm-1 at 50 °C and 98% RH. Although there exist a large number of coordinated or free H2O molecules in both structures, it is easier to form an ordered hydrogen-bonding network between the coordinated H2O molecules in the structure of MOFs, resulting in a more excellent proton conductivity of MOF 1. Moreover, MOF 1 exhibited field-induced single-molecule magnet (SMM) behavior with energy barriers (Ueff) of 37.22 K (τ0 = 9.27 × 10-8 s). Furthermore, MOF 1 exhibits obvious second-order nonlinear optical properties. This research provides guidance for the design of novelty multifunctional MOF materials. [ABSTRACT FROM AUTHOR]

A neutral nickel complex with the extended tetrathiafulvalene-4,5-dithiolate ligand benzotetrathiafulvalenedithiolate (btdt2-) is synthesized and characterized. From the structural analysis, the neighboring molecules in this complex are stacked in a different way compared to the previously reported single-component metal [Ni(tmdt)2]. The computational studies confirm that the difference in molecular packing results in the variance of conductivity. [ABSTRACT FROM AUTHOR]

Two enantiopure one-dimensional complexes with helical structures, [Mn3((R,R)-Salcy)3(H2O)2Fe(CN)6·2H2O]n (1) and [Mn3((S,S)-Salcy)3- (H2O)2Fe(CN)6·2H2O]n (2) [Salcy = N,N′-(1,2-cyclohexanediylethylene)bis(salicylideneiminato) dianion], have been synthesized and characterized. Magnetic studies show that both complexes are ferrimagnets with the magnetic transition temperature at 3 K. [ABSTRACT FROM AUTHOR]

Cleanup goals for sites contaminated with persistent organic pollutants (POPs) are often established based on total contaminant concentrations. However, mounting evidence suggests that understanding contaminant bioavailability in soils is necessary for accurate assessment of contaminant exposure to humans via oral ingestion pathway. Animal-based in vivo tests have been used to assess contaminant bioavailability in soils; however, due to ethical issues and cost, it is desirable to use in vitro assays as alternatives. Various in vitro methods have been developed, which simulate human gastrointestinal (GI) tract using different digestion fluids. These methods can be used to predict POP bioavailability in soils, foods, and indoor dust after showing good correlation with in vivo animal data. Here, five common in vitro methods are evaluated and compared using PAHs and PBDEs as an example of traditional and emerging POPs. Their applications and limitations are discussed while focusing on method improvements and future challenges to predict POP bioavailability in different matrices. The discussions should shed light for future research to accurately assess human exposure to POPs via oral ingestion pathway. [ABSTRACT FROM AUTHOR]

A novel CdII-based two-fold interpenetrated metal--organic framework (MOF), namely {[Cd2(BTDB)2(4,4-bpy)]·DMF}n (JXUST-14), (H2BTDB = 4,4'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic acid and 4,4-bpy = 4,4-bipyridine), has been prepared and characterized. Single-crystal structure determination reveals that JXUST-14 has a tetranuclear cluster based 6-connected pcu topological network with Schlafli symbol {412·63}. When soaked in common organic solvents and aqueous solutions with diverse pH values of 2-12 for 48 h, JXUST-14 remains stable. JXUST-14 is a highly selective and sensitive luminescent sensor for L-histidine (His) with a detection limit of 11.1 ppm. JXUST-14 is the first CdII-based MOF for the detection of His via turn-on and fluorescence blue-shift effects. Experimental study and theoretical calculation suggest that the sensing process can be mainly attributed to a charge transfer and energy transfer mechanism. More interestingly, LED lamps of JXUST-14 and JXUST-14@His were successfully developed, which endowed efficient sensitivity for His detection and thus provide great potential for future applications. [ABSTRACT FROM AUTHOR]

Monodispersed spheres (1-4 μm in diameter) of BaWO:Eu (hereafter BWO:Eu) red-phosphor exhibiting intense emission at 615 nm were synthesized via a mild hydrothermal method. X-ray diffraction, scanning electron microscope, photoluminescence excitation and emission spectra, and decay curve were used to characterize the properties of BWO:Eu phosphors. An intense red emission was obtained by exciting either into the L state with 394 nm or the D state with 465 nm, that correspond to two popular emission lines from near-UV and blue LED chips, respectively. The values of Ω experimental intensity parameters (13.8 × 10 and 8.2 × 10 cm) are determined. The high-emission quantum efficiency of the BWO:Eu phosphor suggests this material could be promising red phosphors for generating white light in phosphor-converted white light-emitting diodes. [ABSTRACT FROM AUTHOR]

The article describes how a previously unreported dianion can affect the crystallization of polymeric metal complex cations. The structures of both title compounds are described in detail. It examines the two-coordinate Ag structure features of the title compounds. Also illustrated are the two-dimensional supramolecular layered architectures of the title compounds.

Six new coordination polymers (CPs) based on the V-shaped 1,3-bis(benzimidazolyl)benzene (bbib) have been synthesized under solvothermal conditions: [Zn(bbib)(ip)]n (1), {[Zn(bbib)(oba)]·solvents}n (2), {[Zn(bbib)(tp)]·DMF}n (3), [Cd(bbib)(ip)]n (4), {[Cd(bbib)(oba)]·H2O·solvents}n (5) and {[Cd(bbib)(tp)]·DMF}n (6) (ip = isophthalate, oba = 4,4′-oxybisbenzoate and tp = terephthalate). Complexes 1-3 display a plane minimal net, (4,4) sheet and a hexagonal plane net, respectively. The structures of 4-6 range from a 1D zigzag chain (4), 2D (4,4) sheet (5) to a 3D "pillar-layer" coordination framework with pcu α-Po topology (6). The structural transition from 1D to 3D among these complexes is realized with the aid of different auxiliary ligands. The results demonstrate that the conformations and coordination modes of dicarboxylate ligands make an impact on the structural diversity of ZnII/CdII coordination polymers. To the best of our knowledge, the CPs based on the bbib ligand have been successfully prepared for the first time. Moreover, complex 2 is a good bifunctional chemosensor for the detection of both Fe3+ and MnO4 - with the detection limits of 3.31 ppm and 8.81 ppm, respectively, indicating that 2 could be used as an efficient fluorescent sensor with high sensitivity and selectivity for Fe3+ and MnO4-. [ABSTRACT FROM AUTHOR]

Four transition metal-organic frameworks were solvothermally synthesized with V-shaped 1,3-bis(1-imidazolyl)benzene (bib) and two Y-shaped carboxylate ligands (1,3,5-benzenetricarboxylic acid (H3btc) and 3,5-pyridinedicarboxylic acid (H2pydc)), namely, {[M2(μ3-OH)(bib)(btc)]·H2O} n (M = Co (1) and Fe (2)) and {[M'2(μ3-OH)(μ2-NO3)(bib)(pydc)]·solvents} n (M' = Co (3) and Ni (4)). All of them are characterized by single-crystal X-ray diffraction, infrared spectrosopy, and powder X-ray diffraction. Both complexes 1 and 2 present two-dimensional (3,8)-connected layer structures, and the point symbol is (3.4²)2(34.46.56.68.7³.8), but Fe2 in 2 is weakly coordinated to O5 as a trigonal bipyramidal geometry compared with the tetrahedral Co2 in 1, while complexes 3 and 4 exhibit three-dimensional "pillar-layer" structures with (3,8)-connected tfz-d net. Interestingly, nitrate anions with a rare μ2-η² coordination mode take part in coordination, and rectangular channels along the c axis exist in 3 and 4. Magnetic studies indicate that 1 and 2 present antiferromagnetic behaviors, while 3 and 4 show the coexistence of spin-canting and long-range magnetic ordering. [ABSTRACT FROM AUTHOR]

Human corneal epithelial (HCE) cells are continually exposed to dust in the air, which may cause corneal epithelium damage. Both water and organic soluble contaminants in dust may contribute to cytotoxicity in HCE cells, however, the associated toxicity mechanisms are not fully elucidated. In this study, indoor dust from residential houses and commercial offices in Nanjing, China was collected and the effects of organic and water soluble fraction of dust on primary HCE cells were examined. The concentrations of heavy metals in the dust and dust extracts were determined by ICP-MS and PAHs by GC–MS, with office dust having greater concentrations of heavy metals and PAHs than house dust. Based on LC 50 , organic extract was more toxic than water extract, and office dust was more toxic than house dust. Accordingly, the organic extracts induced more ROS, malondialdehyde, and 8-Hydroxydeoxyguanosine and higher expression of inflammatory mediators ( IL-1β , IL-6 , and IL-8 ), and AhR inducible genes ( CYP1A1 , and CYP1B1 ) than water extracts ( p < 0.05). Extracts of office dust presented greater suppression of superoxide dismutase and catalase activity than those of house dust. In addition, exposure to dust extracts activated NF-κB signal pathway except water extract of house dust. The results suggested that both water and organic soluble fractions of dust caused cytotoxicity, oxidative damage, inflammatory response, and activation of AhR inducible genes, with organic extracts having higher potential to induce adverse effects on primary HCE cells. The results based on primary HCE cells demonstrated the importance of reducing contaminants in indoor dust to reduce their adverse impacts on human eyes. [ABSTRACT FROM AUTHOR]

Spontaneous resolutions from an in situ reaction especially for a Sharpless reaction are really rare. Here we display a new pair of enantiomeric compounds Δ- and Λ-[Mn(4-tzba)(bpy)2·H2O](bpy)·3H2O (labeled as Δ-1 and Λ-1 respectively) (4-tzba = 4-tetrazolbenzoic acid; bpy = 2,2′-bipyridine) from a Sharpless reaction. They crystallized in the P212121 chiral space group and demonstrated strong second harmonic generation (SHG) responses and red photoluminescence property. The chiral metal conformations were captured by the introduction of the distorted bpy and the in situ synthesized 4-tzba ligands. The hydrogen bonds connecting the 4-tzba and central metal play a crucial role in the chirality transmission, as well as the donor-acceptor type SHG nonlinear response. [ABSTRACT FROM AUTHOR]

Molecular ferroelectrics with high-temperature reversible phase-transition behaviors are very rare and have currently become one of the hotspots in the field of ferroelectric materials. Herein we display two new crown ether clathrates possessing unusual high-temperature ferroelectric phase-transition behaviors, cyclohexyl ammonium 18-crown-6 tetrafluoroborate (or perchlorate), [Hcha-(18-crown-6)]+ [BF4]- (1) and [Hcha-(18-crown-6)]+[ClO4]- (2) (Hcha = protonated cyclohexyl ammonium). We have proven their reversible structural phase transitions by variable-temperature PXRD measurements and temperature evolutions of Raman bands. Both clathrates exhibit clear ferroelectric phase transitions at about 397 and 390 K, respectively, revealed by the thermal anomalies of differential scanning calorimetry (DSC) measurements, together with abrupt dielectric anomalies in the heating and cooling processes. The measurements on ferroelectric properties using the single crystals showed optimized spontaneous polarization (Ps) of ca. 3.27 μC cm-2 for 1 and 3.78 μC cm-2 for 2. [ABSTRACT FROM AUTHOR]

Although a number of acentric or chiral tetrazole complexes were synthesized from Sharpless reaction, there are no spontaneous resolution Cu(I)-tetrazole compounds from in situ [2 + 3] cycloaddition synthesis that have been reported before. The first enantiomers Δ- and Λ- of metal tetrazole compound [Cu(Tzmp)]n (1) (HTzmp = 3-tetrazolemethylpyridine) were obtained and isolated from in situ [2 + 3] cycloaddition reactions of a flexible organic nitrile (3-cyanomethylpyridine) with sodium azide in the presence of CuCl2 as the Lewis acid. Δ-1 and Λ-1 feature a homochiral helical coordination polymeric system and {4(4).6(2)} two-dimensional framework. The photoluminescence study suggests 1 exhibits strong green fluorescence in solid state with maximal emission peaks around 535 nm. Remarkably, the Δ- and Λ- of [Cu(Tzmp)]n (1) catalyzes the enantioselective Henry reaction with high yield (more than 96%) and certain enantioselectivity (up to 69%). [ABSTRACT FROM AUTHOR]

A new series of mononuclear copper(l) complexes (l-- 9) with functionalized 3-(2'-pyridyl)-l,2,4-triazole chelating ligands, as well as the halide and/or phosphine ancillary ligands, have been synthesized. Complexes 1--9 were fully characterized by elemental analysis, NMR spectroscopy, mass spectroscopy, electronic absorption spectroscopy, fluorescence spectroscopy, cyclic voltammetry, and X-ray crystallography (1--8). They adopt a distorted tetrahedral configuration, and are considerably air-stable in solid state and in solution. All these Cu(l) complexes display a comparatively weak low-energy absorption in CH2C12 solution, assigned to charge-transfer transitions with appreciable MLCT character, as supported by TD-DFT studies. Cu(l) halide complexes 1--4 each shows bright solid-state emission at room temperature, although they are nonemissive in fluid solutions, in which the emission markedly depends on the halide and the substituent on the 2-pyridyl ring. Complexes 5--9 bearing 2-pyridyl functionalized 1,2,4-triazole and phosphine exhibit good photoluminescence properties in solution and solid states at ambient temperature, which are well-modulated via the alteration of the auxiliary phosphine ligand and the structural modification of 3-(2'-pyridyl)-l,2,4-triazole. Interestingly, cationic complex 6 and neutral derivative 7 can readily be interconverted through die ring inversion of the 1,2,4-triazolyl regulated by the NH N~ transformation. [ABSTRACT FROM AUTHOR]

Three new mononuclear copper(I) halide complexes of 2-(2-benzimidazoly)-6-methylpyridine (Hbmp), [Cu(Hbmp)(PPh3)X] (X = I (1); Br (2); Cl (3)), have been synthesized and structurally characterized by X-ray crystallography. It is revealed that the most significant impact of the auxiliary halide ligand on the structure is on the Cu一Npyridyl and Cu一P bond lengths. Complexes 1–3 show a weak low-energy absorption band at 350–600 nm in CH2Cl2, ascribed to the Cu(I) to Hbmp metal-to-ligand charge-transfer (MLCT) transitions, perhaps mixed with some halide-to-ligand charge-transfer (XLCT) character. The solid-state emissions of 1–3 are observed at ambient temperature, markedly depending on the halide ancillary ligand bound to the {Cu(Hbmp)(PPh3)} unit, which are assigned to the MLCT excited states with some mixing of the XLCT characters. [ABSTRACT FROM AUTHOR]

A novel family of iridium(III) bis-tridentate complexes are reported that contain the deprotonated, N∧N∧N-coordinated 6-(5-trifluoromethylpyrazol-3-yl)-2,2′-bipyridine (fpbpyH) ligand. The monocationic homoleptic iridium(III) complex [Ir(fpbpy)2](PF6) (1) was first prepared by treatment of IrCl3·3H2O with 2.2 equiv of fpbpyH in degassed ethylene glycol at 196 °C and structurally characterized by single-crystal X-ray crystallography. The reaction of Ir(tpy)Cl3with an equimolar amount of fpbpyH under comparable conditions generated a dicationic heteroleptic iridium(III) complex, [Ir(fpbpy)(tpy)](PF6)2(2), featuring one 2,2′:6′2′′-terpyridine (tpy) in place of one fpbpy. The charge-neutral heteroleptic complex [Ir(fpbpy)(dppy)] (3) (dppyH2= 2,6-diphenylpyridine) was also afforded successfully via a solvent-free method, giving a complex with one dppy bound to the Ir(III) ion through two carbon atoms for the cyclometalation reaction. Complexes 1−3are emissive in acetonitrile solution at ambient temperature, perhaps best assigned to the MLCT character, mixed with intraligand charge transfer (ILCT) transition inside fpbpy and ligand-to-ligand charge transfer (LLCT) π(fpbpy) → π*(tpy) or π(dppy) → π*(fpbpy) transition, respectively, which are supported by DFT calculations. It is noteworthy that the photoluminescence of 3displays a significant red-shifting compared to those of 1and 2due to the large reduction of the HOMO−LUMO energy gap as a consequence of the introduction of the more electron-donating and strong ligand-field cyclometalate dppy chelate. [ABSTRACT FROM AUTHOR]

The title complex, [Co(C12H8N2)(H2O)4](C10H6O6S2)·2H2O, was synthesized hydrothermally. The Co2+ cation, which lies on a twofold rotation axis, is six-coordinate. The anion is located on a centre of inversion. An extensive network of O—H⋯O hydrogen bonds links the components into a threedimensional network. [ABSTRACT FROM AUTHOR]

The title polymer, [Cu(C6H5O6PS)(C10H8N2)(H2O)] n, was synthesized by a hydrothermal method. The CuII ion is five-coordinated by one phosphonate O atom, one sulfonate O atom, two N atoms of the bipyridyl ligand and one water molecule. The coordination geometry around the metal centre can be described as slightly distorted square-pyramidal. The CuII ions are connected by bidentate bridging phosphonato-benzenesulfonate ligands, forming one-dimensional helical chains along [010], which are further bridged by bidentate 4,4′-bipyridyl ligands, generating a two-dimensional layered crystal structure. The layered structure features an eight-membered ring including four CuII ions, two [O3S–C6H4–PO3H]2− anions and two 4,4′-bipyridyl ligands. Hydrogen bonds involving aqua ligands, phosphonate O and sulfonate O atoms are observed between the layers, [ABSTRACT FROM AUTHOR]

Hydrothermal reactions of aluminum(III) nitrate or iron(III) nitrate with N,N-dimethylaminomethane-1, 1-diphosphonic acid (H4L) and sodium hydroxide lead to two novel isostructural octanuclear metal phosphonate cages encapsulating two NaI ions, namely, [Al8Na2(HL)2(H2L)10(H2O)6]·20H2O (1) and [Fe8Na2(HL)2(H2L)10·(H2O)6]·22H2O (2). The molecular structure of 1 can be viewed as a three-in-one cluster, in which a central zeolite D6R SBU lookalike aluminophosphonate cage is capped by two symmetry-related aluminophosphonate tetrahedral cages above and below and such a tetrahedral cage, being composed of four zeolite S6R SBU lookalike aluminophosphonate rings, further hexadentately traps one Na+ ion in its cavity. [ABSTRACT FROM AUTHOR]

Indoor dust often contains organic contaminants, which adversely impacts human health. In this study, the organic contaminants in the indoor dust from commercial offices and residential houses in Nanjing, China were extracted and their effects on human breast cancer cells (MCF-7) were investigated. Both dust extracts promoted proliferation of MCF-7 cells at ≤24 μg/100 μL, with cell viability being decreased with increasing dust concentrations. Based on LC 50 , house dust was less toxic than office dust. At 8 μg/100 μL, both extracts caused more MCF-7 cells into active cycling (G2/M + S) and increased intracellular Ca2+ influx, with house dust inducing stronger effects than office dust. Further, the expression of estrogen-responsive genes for TFF1 and EGR3 was enhanced by 3-9 and 4-9 folds, while the expression of cell cycle regulatory genes for cyclin D was enhanced by 2-5 folds. The results suggested that organic dust extract influenced cell viability, altered cell cycle, increased intracellular Ca2+ levels, and activated cell cycle regulatory and estrogen-responsive gene expressions, with house dust showing lower cytotoxicity but higher estrogenic potential on MCF-7 cells. The results indicate the importance of reducing organic contaminants in indoor dust to mitigate their adverse impacts on human health. Unlabelled Image • Effects of organic dust extract on human breast cancer cells (MCF-7) were examined. • Both extracts stimulated proliferation of MCF-7 cells at ≤24 μg/100 μL. • Extracts reduced cell viability, altered cell cycle and enhanced intracellular Ca2+. • Extracts increased expression of estrogen-responsive & cell cycle regulatory genes. • House dust induced lower toxicity but higher estrogenic potential on MCF-7 cells. [ABSTRACT FROM AUTHOR]