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Bi0.5(Na0.82K0.18)0.5TiO3(NKBT) lead-free ferroelectric thick films with various porosities have been produced by screen printing. Their microstructures, pyroelectric and piezoelectric properties were investigated with variation of porosity. The results show that the relative dielectric constant of the resulting 90 μm NKBT thick films with 19% and 32% porosity was down to 161 and 56, respectively. The pyroelectric voltage figure of merit ( Fv) and detectivity figure of merit ( FD) of NKBT thick films were increased from 10.2 × 10−13 to 19.7 × 10−13 Cm/J and 1.1 × 10−5 to 3.8 × 10−5 Pa−0.5. Moreover, the hydrostatic voltage constant and hydrostatic figure of merit of the NKBT thick films with 32% porosity reached 81 × 10−3 V/mPa and 8200 × 10−15 Pa−1 respectively. The decreasing of relative dielectric constant, volume specific heat, and piezoelectric coefficient with increasing porosity was responsible for the improved pyroelectric and piezoelectric figures of merit of the NKBT thick films. Furthermore, screen printing with the addition of controlled fraction of organic vehicle in pastes has been proved to be an alternative method for fabrication of porous pyroelectric and piezoelectric thick films. Our work demonstrates that introduction of pores in ferroelectric thick films creates a matrix void composite resulting in high figures of merit for pyroelectric and piezoelectric applications. [ABSTRACT FROM AUTHOR]

La2O3-doped sodium–potassium bismuth titanate (Na0.82K0.18)0.5Bi0.5TiO3 (NKBT) lead-free thick films have been prepared on Pt-electroded alumina substrates using a combination of screen printing and subsequent infiltration of the corresponding composite sol. Their densification, microstructure, dielectric, ferroelectric, pyroelectric, and piezoelectric properties were investigated with variation of the La2O3 content. The resulting 40 μm-thick NKBT films doped with 1.0 mol% La2O3 show minimum leakage current density of 1.56 × 10−9 A/cm2 at an applied field of 100 kV/cm, remanent polarization of 21.6 μC/cm2, and coercive field of 58 kV/cm. The high pyroelectric coefficient of 2.0 × 10−4 C·(m2·°C)−1, the calculated detectivity figure of merit as high as 0.81 × 10−5 Pa−0.5, and the value of remanent d33eff of 108 pm/V at room temperature (20°C) were observed in 1.0 mol% La2O3-doped NKBT thick films, which can be comparable with that of the commonly used lead-based materials. The enhancement of the pyroelectric and piezoelectric performances is attributed to the reduction of lattice tetragonality, uniform microstructure, and improved densification in La-modified NKBT thick films. [ABSTRACT FROM AUTHOR]

MnO-doped 0.82Bi0.5Na0.5TiO3–0.18Bi0.5K0.5TiO3(NBT–KBT) thick films with thickness about 40 μm have been prepared using screen printing on Pt electroded alumina substrates. The strong pyroelectric coefficient of 3.8 × 10−4 C·(m2·°C)–1 was observed in 1.0 mol% MnO-doped-thick films, and the calculated detectivity figure of merit as high as 1.1 × 10−5 Pa−0.5, which can be comparable to that of the commonly used lead based materials. The enhancement of the pyroelectric performances is attributed to the reductions in dielectric constant and loss and the improvements in the pyroelectric coefficient, which can be ascribed to the Mn acts as a hard dopant in the NBT–KBT lattice, creating oxygen vacancies and pinning the residual domains. [ABSTRACT FROM AUTHOR]

Organochlorine pesticides were used extensively in the Yangtze River Delta, China. However, knowledge about their residual levels and environmental fates in soils of this area is limited. This paper presents the residue isomers and spatial pattern of dichlorodiphenyltrichloroethane (DDT) in soils across 17 main cities in the Yangtze River Delta. Forty-three soil surface (0-15 cm) samples were collected during a field campaign conducted in October 2003 in the Delta. Six DDT isomers (1-[2-chlorophenyl]- 1-[4-chlorophenyl]-2,2-dichloroethane [o,p'-DDD], 1-[2-chlorophenyl]-1-[4-chlorophenyl]-2,2-dichloroethylene [o,p-'DDE], 1,1,1- trichloro-2-[p-chlorophenyl]-2-[o-chlorophenyl]ethane [o,p'-DDT], p,p'-dichlorodiphenyldichloroethane [p,p'-DDD], p,p'-dichlorodiphenyldichloroethylene [p,p'-DDE], p,p'-dichlorodiphenyltrichloroethane [p,p'-DDT]) were detected using gas chromatography. The results show that p,p'-DDE was the dominant isomer in the soil samples. The levels of DDT are generally low in soils of this area and are comparable to DDT levels in other cities in China and in soils from developed countries such as the United States and Germany. The isomer ratios of o,p'-DDT to p,p'-DDT and DDT to (DDD + DDE) were employed to identify the source of DDT. The computed ratios implied that the source of DDT might be related to the application of dicofol, an acaricide manufactured from technical DDTs and mainly used on cotton fields to treat mites. [ABSTRACT FROM AUTHOR]

A novel [2]pseudorotaxane of cucurbit[6]uril(CB[6]) and 1-butyl-3-methyl-imidazolium bromide ([C4mim]Br) was synthesized by directly mixing the host and the guest molecules in non-aqueous system. Structural characterizations of the [2]pseudorotaxane were carried out by 1D, 2D NMR and X-ray crystallography techniques both in solution and in crystal structure. The crystal structure demonstrated that CB[6] and [C4mim]Br formed a complex with the ratio 1:1, in which one guest [C4mim]Br was included inside the CB[6], while two other [C4mim]Br molecules were free and surrounded the [2]pseudorotaxane as solvent molecules, which could stabilize the crystal structure through hydrogen bonds. Moreover, parallel solvent channels consisting by free [C4mim]Br molecules occupied the pores among the frame of the pseudorotaxanes and formed zigzag lines in the crystal structure. [C4mim]Br can serve as not only the guest reactant but also the solvent in the formation of [2]pseudorotaxane formation. [ABSTRACT FROM AUTHOR]

This review focuses on the research literatures published in 2016 relating to thermal effects in water pollution control. This review is divided into five sections: biological nitrogen removal, organic pollutant degradation, resource recovery, pretreatment and anaerobic digestion, microbial community. [ABSTRACT FROM AUTHOR]

Identification of nitrogen (N) sources is important in water quality control and management. Nitrogen pollution can lead to eutrophication of waterbodies and high concentrations of nitrate in drinking water can pose potential health problems. The 15N isotope and nitrogen fluxes budget approach is useful for determining the source of NO-3 to surface waters. In this study, mass balance and bN isotope approaches and nitrogen flux budgets were applied to identify total nitrogen (TN) sources and nitrogen transformation processes in the Menlou Reservoir (MR), Jiaodong Peninsula, China. The different fractions of nitrogen and their 15N isotope signatures were analyzed in the reservoir water, river water, groundwater, soil, and atmospheric precipitation. The results indicate that surface runoff pollution (e.g., fertilizer and animal manure) is the main source of NO-3 in MR. High concentrations of TN in MR are caused by low nitrogen self-purification (denitrification) rate, low sediment adsorption capacity, and the influx of NOJ rich groundwater. [ABSTRACT FROM AUTHOR]

Hacs1, a SH3 and SAM domain-containing adaptor protein, is up-regulated by IL-4 in activated B cells and strongly expressed in dendritic cells. To elucidate the function of Hacs1 in immune regulation, we generated Hacs1-/- mice by deletion of the SH3 and SAM domains. Hacs1-/- mice were viable and fertile and had normal bone marrow B-cell development and normal splenic T- and B-cell populations. However, adult Hacs1-/- mice had increased peritoneal B1a cells (IgM+CD5+). On immunization with T-cell-independent antigen TNP-Ficoll, Hacs1-/- mice had increased production of anti-TNP IgM and IgG3. Purified splenic B cells from Hacs1-/- mice showed increased cell proliferation on BCR (B-cell receptor) stimulation. We further demonstrate that the Hacs1-/- B cells had increased global tyrosine phosphorylation, including tyrosine kinases Lyn and Akt. Both T-helper type 1 (Th1) and T-helper type 2 (Th2) humoral responses were enhanced in Hacs1-/- mice. In vitro bone marrow-derived Hacs1-/- dendritic cells showed increased IL-12 production on stimulation with ovalbumin (OVA). This study suggests that Hacs1 is an immunoinhibitory adaptor that might be a useful target for immune suppression therapy. [ABSTRACT FROM AUTHOR]

Human neutrophil peptides (HNP) kill microorganisms but also modulate immune responses through upregulation of the chemokine IL-8 by activation of the nucleotide P2Y6 receptor. However, the intracellular signaling mechanisms remain yet to be determined. Human lung epithelial cells (A549) and monocytes (U937) were stimulated with HNP in the absence and presence of the specific kinase inhibitors for Src, extracellular signal-regulated kinase-1 and -2 (ERK1/2), p38 mitogen-activated protein kinase (MAPK), c-Jun-N-terminal kinases (JNK), and Akt. HNP induced a rapid phosphorylation of the kinases in both cell types associated with a dose-dependent, selective production of IL-8 among 10 cytokines assayed. The HNP-induced IL-8 production was blocked by the Src tyrosine kinase inhibitor PP2, MEK1/2 inhibitor U0126, and the phosphatidylinositol 3 kinase (PI3K) inhibitor LY294002, but not by the JNK inhibitor SP600125 in both cell types. Treatment with the p38 inhibitor SB203580 attenuated the HNP-induced IL-8 production only in monocytes. Blockade of Src kinase blunted HNP-induced phosphorylation of the ERK1/2 and Akt but not p38 in monocytes. In contrast, Src inhibition had no effect on phosphorylation of the other kinases in the lung epithelial cells. We conclude that the activation of ERK1/2 and PI3K/Akt pathways is required for HNP-induced IL-8 release which occurs in a Src-independent manner in lung epithelial cells, while is Src-dependent in monocytes. J. Cell. Physiol. 214: 820–827, 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]