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Highly nonlinear optical 4-N, N-dimethylamino-4-N-methyl stilbazolium tosylate (DAST) crystals with large surface and thickness was grown by the slope nucleation technology with slow-cooling in a high concentration solution. The structure and composition of the crystal were confirmed by X-ray diffraction (XRD). The surface morphology of the crystal was characterized by optical microscope. Growth layers were observed on the (001) surface and several isolated “island layers” were also found. The mechanism of crystal growth was analyzed. Etching behavior of the (001) and ( 00 1 ¯ ) faces of the crystal was studied with methanol, respectively. Optical properties of the crystal were also characterized by UV–vis–NIR spectrometer. The dielectric constants and the dielectric loss were tested by impedance analyzer. [ABSTRACT FROM AUTHOR]

The challenge of simultaneous removal of nitrobenzene (NB), aniline (AN) and nitrate from groundwater in a single bioreactor is mainly attributed to the persistence of AN to degradation with anoxic denitrification conditions. In this work, simultaneous removal of NB (100 μM), AN (100 μM) and nitrate (1 mM) was achieved within 8 h with a COD/N ratio of 8 in a vertical baffled biofilm reactor (VBBR). By setting DO concentration at 0.4–0.5 mg L−1 to create a micro-aerobic condition, NB removal rate was accelerated without accumulation of AN, and AN could serve as electron donors for denitrification after ring cleavage. High-throughput sequencing showed that biofilm was predominated by denitrifiers (Luteimonas , Planctomyces , Thiobacillus , Thauera and so on) and NB-degrading bacteria (Pseudomonas), and biodiversity varied vertically along the height of the reactor. A dominantly anaerobic pathway for reducing NB to AN was identified by PICRUSt analysis, as the predicted genes involved in aerobic transformation of NB were several magnitudes lower than those in the anaerobic pathway. This study provided a new insight to the role of oxygen in robust bioremediation groundwater contaminated with NB, AN and nitrate. [Display omitted] • Simultaneous removal of NB, AN and nitrate was achieved in a VBBR. • AN could serve as electron donors for denitrification only in the presence of O 2. • Biofilm was predominated by denitrifiers and NB-degrading bacteria. • A dominantly anaerobic pathway for reducing NB to AN was identified. [ABSTRACT FROM AUTHOR]

The 4-N,N-dimethylamino-4-N-methyl stilbazolium tosylate (DAST) crystal with large size and nearly square shape was grown in high concentration solution by slope nucleation method coupled slow cooling (SNM-SC). Striations considered as planar defects were found on the (0 0 1) face along a -axis in the crystal by optical microscope. Some of the striations were continuous while some of them were discontinuous. In addition, the striations were found on (2 3 1) diffracting face and such lines did not occur on the (3-21) and (−2 2 1) planes. The surface distribution and morphological structure of the crystal were characterized by XRD and atomic force microscope (AFM). The presence of striations in the sample was also confirmed by white-beam synchrotron radiation topography (WBSRT). The mechanism of striations formation was also discussed. [ABSTRACT FROM AUTHOR]

Vertical baffled biofilm reactors (VBBR) equipped with Plastic-carriers and Fe-carriers were employed to explore the effect of biofilm carriers on biofilm formation and p -nitrophenol (PNP) degradation. The results showed that Fe-carriers enhanced biofilm formation and PNP degradation. The maximum thickness of biofilm grown on the Fe-carriers was 1.5-fold higher than that on the Plastic-carriers. The Fe-VBBR reached a maximum rate of PNP removal at 13.02 μM L−1 h−1 with less sodium acetate addition (3 mM), while the maximum rate of PNP removal was 11.53 μM L−1 h−1 with more sodium acetate addition (6 mM) in the Plastic-based VBBR. High-throughput sequencing suggested that the Fe-VBBR had a higher biodiversity of the bacterial community in evenness, and the Achromobacter genus and Xanthobacteraceae family were as main PNP degraders. Kyoto Encyclopedia of Genes and Genomes (KEGG) Orthology analysis suggested more abundances of iron uptake genes were expressed to transport iron into the cytoplasm under an iron-limited condition in two VBBRs, and the metabolic pathway of PNP degradation went through 4-nitrocatechol and 1,2,4-benzenetriol. Our results provide a new insight for iron enhancing biofilm formation and PNP degradation. [Display omitted] • Fe-carriers can promote biofilm formation and PNP degradation. • More iron uptake genes were expressed under iron-limited conditions. • Plastic-VBBR had a lower community diversity than Fe-VBBR. • Achromobacter genus and Xanthobacteraceae family may be as PNP degraders. [ABSTRACT FROM AUTHOR]

Abstract: Raman measurements of xCaF2–Ag(Nb,Ta)O3 perovskite ceramics, with x =0, 4, 4.5, and 5wt.%, are taken at room temperature. Raman spectra of the ceramics are analyzed through the characteristic parameters: peak position and line width of phonon modes. With the increase in CaF2 concentration, the vibration frequency of A1g(Ag) phonon, as well as the full-width-at-half-maximum (FWHM), decreases. The decrease in vibration frequency of A1g(O) mode indicates that Nb–O and Ta–O bonds become weak. These suggest that the addition of CaF2 leads to the distortion of (Nb,Ta)O6 octahedra. In addition, the increase in the width of A1g(O) stretch mode leads to the increase in permittivity and the decrease in dielectric loss of the ceramics. These conclude that the (Nb,Ta)O6 octahedra play an important role on dielectric properties of xCaF2–Ag(Nb,Ta)O3 ceramics. [Copyright &y& Elsevier]

Abstract: Novel soluble porphyrin–bisindolylmaleimides dyad and pentamer have been prepared conveniently by coupling of amino-porphyrins and bisindolylmaleic anhydride. The bisindolylmaleimide groups function as the antenna to efficiently enhance the intramolecular energy transfer to the porphyrin core. These compounds may serve as good candidates of red-light emitting materials for organic light-emitting diodes. [Copyright &y& Elsevier]

Abstract The organic crystal 4-chlorobenzaldehyde -N- methyl 4-stilbazolium tosylate (CMST) was grown from acetonitrile and methanol mixed solvent using slow cooling method for the first time. The optimum growth conditions based on different solution concentrations were investigated. The crystal atomic packing and bond length alternation (BLA) of CMST were identified through single crystal X-ray diffraction analysis, the calculated BLA value 0.1475 Å is close to optimum value for nonlinear optical (NLO) response. The composition and different functional groups of CMST compound were determined by 1H NMR and FT-IR studies. Moreover, the thermal stability and melting point were obtained through TG/DTG and DSC analyses. Important optical parameters such as optical transmittance, cut-off wavelength, absorption coefficient, band gap energy and refractive index were ascertained through UV–vis-NIR study, the low cut-off wavelength and wide optical transmittance of CMST crystal are favorable to optical device fabrication. The dielectric constant has been investigated. Green emission occurred at 521 nm was found through photoluminescence excitation study. These encouraging results suggest that the CMST crystal is a promising candidate for nonlinear optical device applications. [ABSTRACT FROM AUTHOR]

PFASs and chlorinated solvents are the common co-contaminants in soil and groundwater at firefighter training areas (FTAs). Although PFASs mixtures could have adverse impacts on bioremediation of trichloroethylene (TCE) by inhibiting Dehalococcoides (Dhc), little is known about the effect and contribution of PFOA or PFOS on dechlorination of TCE by non- Dhc organohalide-respiring bacteria (OHRB). To study this, PFOA and PFOS were amended to the growth medium of a non- Dhc OHRB-containing enrichment culture to determine the impact on dechlorination. This study demonstrated that high levels of PFOA or PFOS (100 mg L–1) inhibited TCE dechlorination in four non- Dhc OHRB-containing community including Geobacter, Desulfuromonas, Desulfitobacterium , and Dehalobacter , but low levels of PFOA or PFOS (≤10 mg L–1) enhanced TCE dechlorination. Four non- Dhc OHRB were less inhibited by PFOA than that by PFOS, and high level of PFOS killed Desulfitobacterium and Dehalobacter and decreased the biodiversity of bacterial community. Although most fermenters were killed by the presence of 100 mg L–1 PFOS, two important co-cultures (Desulfovibrio and Sedimentibacter) of OHRB were enriched, indicating that the syntrophic relationships between OHRB and co-cultures still remained, and PFOA or PFOS inhibited TCE dechlorination by directly repressing non- Dhc OHRB. Our results highlight that the bioattenuation of chloroethene contamination could be confounded by non- Dhc OHRB in high levels of PFOS contaminated subsurface environments at FTAs. [Display omitted] [ABSTRACT FROM AUTHOR]

A new NLO chalcone crystal 1-(2-furyl)-3-(4-methylthio phenyl)-2-propen-1-one (FTMS) was successfully designed and the crystal was grown by slow evaporation solution growth technique. The cell data and structure refinement were determined from the single crystal X-ray diffraction. It was found that the SHG efficiency intensity of FTMS was 18 times that of KDP. The thermal decomposition temperature of FTMS was observed at 235 ℃. The crystal has a high transmittance (95%) in 500–2000 nm with a cutoff wavelength of 405 nm. [ABSTRACT FROM AUTHOR]

This study investigates a pyridinium-based NLO crystal 4-N, N-dimethylamino-4′-N′-methyl-stilbazolium 3,4-dimethoxysulfonate (DOST) containing the strong electron donor, which act the electron and hydrogen bond donors. A DOST signal crystal with a size of 2 × 5 × 1 mm3 has been grown in methanol solution by the slow cooling growth method. Physical property measurements indicate DOST crystal possesses a strong second harmonic generation response that is 8 times that of KH 2 PO 4 (KDP) crystal and a bandgap of 2.90 eV, making it very promising for nonlinear optical applications. The NLO properties as dipole moment, polarizability, first order hyperpolarizability are performed using density functional theory (DFT) method. Benefiting for the near-perfect alignment of DOS cations, DOST crystal exhibits a large diagonal component of the effective hyperpolarization, about 105.21 × 10−30 esu. Furthermore, information about the sites of intermolecular interaction has been obtained by molecular electrostatic potential (MEP) surface and Hirshfeld Surface. In order to understand the electronic properties, the absorption wavelengths, excitation energies, oscillator strength, the frontier molecular orbitals and global reactivity descriptors are also calculated. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The crystal structure and microwave dielectric properties of ZnTi(Nb1−x Ta x )2O8 ceramics were investigated. The ZnTi(Nb1−x Ta x )2O8 ceramics mainly contained ixiolite structure phase ZnTiNb2O8 and an unknown Columbite-type phase. The change of microwave dielectric properties was affected by the change of crystal structure of each phase. In ZnTi(Nb1−x Ta x )2O8 ceramics, the Columbite structure phase with increasing degree of ordering led to decrease of dielectric constant, increase of Qf, and to τf moving in the positive direction. The ZnTiNb2O8 with decreasing cation valence led to the increase of τf . The typical values were: ε = 34.05, Qf = 40,000 GHz, τf  = −66.07 ppm/°C. [Copyright &y& Elsevier]

• Removal of Cl at the para position was key for mineralization of 2,4-DCP. • Bacteria acclimated to 4-CP could rapidly remove Cl at the para position. • Augmenting with 4-CP-dechlorinating bacteria allowed mineralization of 2,4-DCP. • Treponema, Dechloromonas, and Thauera were involved in dechlorinating 2,4-DCP. • Nitrospira and Blvii28 also may play roles in removal of Cl at the para -position. The key step for anaerobic biodegradation of 2,4-dichlorophenol (2,4-DCP) is an initial dechlorination reaction, but Cl in the para- position is more difficult to remove than Cl in the ortho -position using normal 2,4-DCP-acclimated bacteria. In this work, a bacterial community previously acclimated to biodegrading 2,4-DCP slowly dechlorinated 4-chlorophenol (4-CP Cl only in the para -position), which limited mineralization. That community was exposed to the selective pressure of having 4-CP as its only organic substrate in order to generate a 4-CP-dechlorinating community. When the 4-CP-dechlorinating community was challenged with 2,4-DCP, 4-CP hardly accumulated, although the kinetics for 2,4-DCP biodegradation were slower. When the community acclimated to 4-CP was mixed with the community acclimated to 2,4-DCP, the 2,4-DCP removal rate remained high, and 4-CP was more rapidly biodegraded. The genera Treponema , Blvii28, Dechloromonas , Nitrospira , and Thauera were significantly more abundant in the 4-CP-dechlorinating biomass and may have played roles in 2,4-DCP dechlorination and mineralization. [ABSTRACT FROM AUTHOR]

1-(4-methoxyphenyl)-3-(3,4-dimethoxyphenyl)-2-propen-1-one(DMMC), a chalcone derivative was synthesized by Claisen-Schmidt condensation reaction method. The growth of DMMC in methanol was used the slow evaporation technique. Single crystal X-ray diffraction revealed that the space group of DMMC is P2 1. The intermolecular interaction of crystal was analyzed by Hirshfeld surface. The second harmonic generation efficiency of DMMC was measured by Kurtz-Perry powder method. When the particle size was between 250 and 300 μm, the SHG efficiency of DMMC was the largest, which was about 60 times that of the KDP with the same particle size. All functional groups of the crystal were identified by FT-IR and 1H NMR spectral. This crystal had a wide transmission range in the region of 350−2000 nm with the cut off wavelength is 400 nm. The thermal properties of the sample were tested, and the melting point was at 95.59 °C. The dielectric constant of the compounds was found to be 17 below 45 °C. [ABSTRACT FROM AUTHOR]