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In this study, the abilities two kinds of algae, Scenedesmus and Microcystis aeruginosa, and two kinds of bacteria, Rhodococcus and Raoultella planticola, to remove oestradiol when in a symbiotic system were investigated. The effects of the combined systems as well as the effects of each bacterium and algae alone were examined. We then compared the improvements from the bacteria-algae symbiosis systems with Microcystis aeruginosa and Raoultella planticola. The results showed that the oestradiol removal rate of the best system was 97.6%, while that from the Microcystis aeruginosa and Raoultella planticola system was 89%. Oestradiol has an effect on algal growth. The effects of algae on the growth of degrading bacteria were investigated. Degrading bacteria can affect the growth of algae. The symbiosis of bacteria and algae effectively removed oestradiol, with a removal rate that reached 97.6%. [ABSTRACT FROM AUTHOR]

A novel tert-butyl hydroperoxide tetrasubstituted cobalt phthalocyanine (CoPc(OC10H14N)4) was synthesized by the classical phthalonitrile method. Subsequently, the cobalt phthalocyanine (CoPc) was immobilized on the multi-walled carbon nanotubes (MWCNTs) by ultrasonic impregnation method to obtain CoPc(OC10H14N)4/MWCNTs composites. The obtained composites were characterized by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM) and diffuse reflectance spectra (DRS) techniques. Using tert-butyl hydroperoxide (TBHP) as an environmentally friendly oxidant, CoPc(OC10H14N)4/MWCNTs composites can be used as effective catalysts for the epoxidation of styrene. The effects of various variables, such as the mass ratio of CoPc(OC10H14N)4/MWCNTs, reaction time, temperature, molar ratio of substrate/oxidant and the amount of catalyst on the catalytic capability were evaluated. The conversion of styrene reached 97.15%, and the epoxidation product achieved the selectivity of 84.44% under the optimal reaction conditions. [ABSTRACT FROM AUTHOR]

Gradient ceramics based on (1-x)PZT + xBiFeO3(x = 0.01, 0.05, 0.10, Zr/Ti = 95/5) were prepared by a conventional solid-state reaction process. The perovskite structure in the system was confirmed by X-ray diffraction while the microstructure of the composites was characterized by scanning electron microscopy. It was observed that gradient ceramics possess both ferroelectric and ferromagnetic properties at room temperature. A large electromagnetic coupling effect was observed in such gradient system as well. It indicates that gradient ceramics with larger component differences may result in bigger dielectric change under magnetic field. Besides, electromagnetic coupling effect is not directly proportional to magnetism. The related mechanism was discussed with respect to diffusion behavior in the graded material. [ABSTRACT FROM AUTHOR]

La modified Pb(Mg1/3Nb2/3)O3-PbTiO3(PLMNT) transparent electro-optic (EO) ceramics with pure perovskite phase were fabricated by the uniaxial hot-press sintering method. An improved hot-press sintering technique with varied atmosphere was proposed to eliminate the pore defects. It consists of four stages: 1) sintering at a relatively low temperature (800°C) in the vacuum atmosphere first, and then in the pure O2atmosphere; 2) sintering in a pure O2atmosphere at high temperature by uniaxial hot-press method; 3) replacing the O2atmosphere with CO2gas to eliminate the residual closed pores; 4) finally exchanging CO2atmosphere with pure O2gas to eliminate the oxygen vacancies. The research results certified that the thermal treatment in the vacuum atmosphere and CO2atmosphere could eliminate the residual closed pores and improve the transmittance of the PLMNT transparent ceramics effectively. By the improved hot-press sintering technique, the optical transmittance of the polished PLMNT transparent ceramics with a thickness of 0.35mm increases from 61% to 64% at 632.8nm. The reasonable explanation was given about the mechanism of the improvements of this sintering technique. [ABSTRACT FROM AUTHOR]

The effects of sintering temperature on microstructure, phase, electrical and magnetic properties of LiZn ferrites prepared by hot pressing methods were examined systematically. All the ferrites were spinel strustures sintered at the temperature above 1050°C. At higher than 1100°C, pores within the grains appeared due to the volatilization of lithium. The DC electrical resistivity ρ increased firstly and decreased dramatically because of the Fe2+formation. The magnetic properties showed that the saturation magnetization (Ms) increased and coercive field (Hc) decreased with the increasing temperature. The hot pressing method is proven an effective way to obtain the densified LiZn ferrites. [ABSTRACT FROM AUTHOR]

We reported multiferroic ceramics (1-x)PZT +xBiFeO3(x = 0.01–0.10, Zr/Ti = 95/5–100/0) were prepared by a conventional solid-state reaction process. The structures were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD showed that the (1-x)PZT+xBiFeO3samples formed perovskite structure. SEM indicated that the dense ceramics were obtained when the sintering process was modified. It is well known that the PZT95/5 system is a typical ferroelectric material and BiFeO3possesses antiferromagnetic property. It was found that (1-x)PZT+xBiFeO3exhibited both ferroelectric and ferromagnetic properties at room temperature. The relationship between the ferroelectric and ferromagnetic properties was discussed. [ABSTRACT FROM AUTHOR]

Lithium zinc (Li0.35+xZn0.3Mn0.08Fe2.27O4±δ) ferrites with excess lithium concentrationxvarying from 0 to 0.08 in steps of 0.02 were prepared by conventional oxide ceramic method. XRD patterns confirm the spinel structure of Li0.35+xZn0.3Mn0.08Fe2.27O4±δferrites. According to the results of SEM photograph, excess lithium can compensate the volatilization of lithium during the sintering process and an appropriate amount of excess lithium is found to decrease the material porosity obviously, which improves the comprehensive performance of Li-Zn ferrites effectively. As the excess lithium concentration increases, the grain growth is restricted and the average grain size decreases. The bulk densitydand saturation magnetizationMsincrease firstly and then decrease with the increase of Li-excessx. In the meanwhile, the coercive forceHcshows a gradually increasing trend from 190A/m to 1036A/m, and the resistivity ρ has a monotonically increase due to the decrease of Fe2+irons. [ABSTRACT FROM AUTHOR]

(Na0.52K0.48)NbO3-xLiNbO3(KNLN), (Na0.52K0.48)NbO3-xLiSbO3(KNLS), and (Na0.52K0.48)NbO3-xLiTaO3(KNLT) lead-free piezoelectric ceramics were prepared by a solid-state method. A pure perovskite structure was investigated in these samples at room temperature. The ferroelectric domain morphology was observed with piezoresponse force microscope (PFM) technology. It was observed that the excellent dielectric property was acquired with appropriate shrinkage. The related mechanism was discussed. [ABSTRACT FROM AUTHOR]

This paper reports the relationship between the conductive property and the ultraviolet-visible spectrum in Mn-doped BaTiO3-based ceramics. It was observed that the conductance increased with the addition of Mn in BaTiO3. Ultraviolet-visible absorption effects were observed in the pure BaTiO3and the doped BaTiO3ceramics as well. The addition of MnO2resulted in an increase of absorption wavelength. The phenomena were discussed in terms of the change of the band-gap energy between valence band and conduction band. According to the mechanism, similar electrical and optical behaviors were predicted and shown in a parallel system, Mn-doped barium strontium titanate ceramics, Ba0.93Sr0.07TiO3. [ABSTRACT FROM AUTHOR]

Pr-doped barium titanate-calcium titanate with rich barium is prepared by a sol-gel technique. A relatively strong red luminescence is observed in the material when Pr-BaTiO3 material does not exhibit obvious red luminescence. The wavelength range of luminescence near red light is broad. The phenomenon is discussed with respect to the substitute of Ca and the two-photon luminescence effect. The experimental results provide a possible way to develop new materials with photoluminescence properties that can be controlled by external fields because the microscopic structure of BaTiO3 can be changed by temperature, stress, electric field, and so on. [ABSTRACT FROM AUTHOR]

Ferroelectric material possesses a high dielectric constant during ferroelectric to paraelectric phase transition. But, the high dielectric constant exhibits only within a very small temperature window because the phase transition region is narrow. Functionally graded material is suggested to enlarge the phase transition region. Here, both functionally graded ferroelectric ceramics lead titanate zirconate(PZT) and PZT with single composition are prepared. Dielectric property in two systems is measured and compared each other. Functionally graded ceramics PZT possesses a relatively high dielectric constant within a large temperature range. It is due to the FGM PZT has a wide phase transformation temperature region. [ABSTRACT FROM AUTHOR]

The reverse transformation (from ferroelectric to paraelectric phase) temperature in aged ferroeletric lead lanthanum titanate ceramics is measured precisely by differential scanning calorimetry (DSC). It is observed that the transformation temperature increases with increasing aging time, indicating ferroelectric phase is stabilized by aging. This behavior is similar to those in ferroelectric single crystal barium titanate. The origin of the stabilization effect in the system is discussed with respect to the diffusion of point defects. [ABSTRACT FROM AUTHOR]