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Dense ceramics in the solid solution system, Bi4Ti3O12-0.04Fe2O3 (BIT-0.04Fe) ceramics were prepared by conventional solid-state method. And the electrical properties were investigated by the dielectric and impedance spectroscopies. Moreover, the BIT-0.04Fe ceramic exhibit only one loss peak which can be analyzed in terms of the Maxwell-Wagner capacitor model at lower temperature, while the second peak related to the space charge polarization between the ceramic and electrode appeared above 920K. The Arrhenius plot of the total conductivity of BIT-0.04Fe ceramic indicates three different activation energies. The impedance complex plane plots of BIT-0.04Fe ceramic turned into one semicircular arc at 353 K and then to one semicircular arc and a line at 433 K and two single semicircular arcs at 513 K, which were analyzed as three different equivalent circuits.

Dense ceramics in the solid solution system, Ba 0.9 Ca 0.1 Ti 0.9 Zr 0.1 O 3 –0.06Fe 3+ (BCTZ–Fe 3+ ) were prepared by hydrothermal method assisted by microwave sintering. And the electrical properties were investigated by the dielectric and impedance spectroscopies. The ϵ–T /tan δ – T curve revealed relaxor behaviors below Curie temperature ( T C ) and a loss peak’s shifting to higher temperature with increasing frequency. Moreover, the BCTZ–Fe 3+ ceramic exhibits only one loss peak which can be analyzed in terms of the Maxwell–Wagner capacitor model at lower temperature, while the second peak related to the space charge polarization between the ceramic and electrode appeared above 623 K. The impedance complex plane plots of BCTZ–Fe 3+ ceramic turned into one semicircular arc at 473 K from a single line at 373 K and then to two semicircular arcs at 573 K and 643 K, which were analyzed as four different equivalent circuits.

The Dy 3+ doped and Dy 3+ /Ce 3+ co-doped CaO–Al 2 O 3 –SiO 2 –B 2 O 3 glass for light-emitting-diodes (LED) applications had been successfully prepared by the conventional melt-quenching method. Their photoluminescence properties were characterized by excitation and emission spectra. Under UV-light excitation, the Dy 3+ doped CaO–Al 2 O 3 –SiO 2 –B 2 O 3 showed a yellowish white light emission. To compensate for the lack of blue light emitting, Dy 3+ /Ce 3+ co-doped CaO–Al 2 O 3 –SiO 2 –B 2 O 3 glass with the compositions of 0.25Dy 3+ / z Ce 3+ :CaAlSiB ( z =0–0.35 mol%) were prepared, and their photoluminescence properties were studied. The results showed that the white light could be achieved by varying excitation wavelengths and the concentration of Ce 3+ ions. Furthermore, the energy transfer between Dy 3+ and Ce 3+ was also investigated.

Aurivillius phase Bi4Ti3O12–xFe2O3 (BIT–xFe, x = 0–0.08) ceramics were prepared by conventional solid-state method. The crystallographic evolution was determined via the X-ray diffraction patterns, by which the lattice parameters, a, b and c were also calculated. It was found that the increasing content of Fe2O3 reduced the lattice distortion of BIT-based ceramics, which led to a phase transition from orthorhombic to tetragonal. Ferroelectricity and magnetization data showed that BIT–xFe ceramics possess expected ferroelectric and ferromagnetic behaviors. Besides, the grain size decreased as structure changed from rod-like to sphere with increasing x, which can be observed in the SEM. The dielectric constant can be analyzed by a “brick-wall” model, the dielectric loss and dc conductivity had a tendency to decrease with increasing x.

Ceramics in the solid solution system, Ba0.9Ca0.1Ti0.9Zr0.1O3–xBi3+ (x = 0.000–0.030) were prepared by hydrothermal and were assisted by microwave sintering. Effects of Bi3+ content on the phase transition, microstructure, and electrical properties of ceramics were investigated. The single phase perovskite-type ceramics showed different polymorphs and the grain size was significantly influenced with the doping of Bi3+. Dielectric measurements indicated excellent dielectric relaxation behavior for x = 0.005 and x = 0.030. At x = 0.015 and x = 0.020, samples show giant dielectric constant (near 200,000) and lower dielectric loss (lower than 1.2), compared with other giant permittivity materials such as CCTO. The relationship between T C and 2E C was investigated and a novel conclusion of the 2E C was increased with increasing T C was reached. A maximum value of d 33 = 265 pC/N was observed at x = 0.025 for the emergence of T O–T . That is because piezoelectrics always possessed high d 33 near morphotropic phase boundary.

Ceramics in the solid solution system, Ba 0.9 Ca 0.1 Ti 0.9 Zr 0.1 O 3 – x Nd 3+ , were prepared via a hydrothermal method and were assisted by microwave sintering, and the effects of Nd 3+ -doping on the electrical properties of Ba 0.9 Ca 0.1 Ti 0.9 Zr 0.1 O 3 were studied. All the samples showed single perovskite structure without a second phase, and a change from the rhombohedral phase to the coexistence of tetragonal and cubic phase occurred at x ≥0.025. The dielectric constant and dielectric loss both decreased with increasing Nd 3+ content at 0.000≤ x ≤0.015 and the sample with x =0.020 showed giant permittivity with higher dielectric loss. At x =0.025 and 0.030, the T C significantly decreased and the samples exhibited optimistic relaxor behavior with excellent frequency dispersion. The P r decreased with increasing Nd 3+ content and the samples with x =0.025 and 0.030 showed P–E loops with lower polarization loss. The piezoelectric constant ( d 33 ) measured at room temperature increased with increasing Nd 3+ addition and exhibited the maximum value at x =0.025. The ferroelectric and piezoelectric properties could not be detected at samples with x =0.020.

The effect of Zr4+ content on the grain growth, dielectric relaxation, and piezoelectric properties of Ba0.4Sr0.6Ti1−xZrxO3 (BSTZ; x = 0, 0.02, 0.04, 0.06) ceramics prepared by solid-state (SS) and sol–gel modified hydrothermal (SH) methods assisted by fast microwave sintering was investigated in this study. A combination of x-ray diffraction (XRD), scanning electron microscopy (SEM), impedance analysis, and ferroelectric analysis was used. All the ceramics had pure perovskite structures at room temperature, as seen from XRD patterns, indicating that Zr4+ was incorporated into Ba0.4Sr0.6TiO3 lattices to form a solid solution. In the SEM micrographs, SH samples had higher densities and smaller and more homogeneous grain size than SS samples, which was in agreement with density measurements. Nano-ceramics were obtained by this method. When the temperature dependence of dielectric constant and dielectric loss was studied, SH samples had higher permittivity, better thermally activated relaxation, and lower dielectric loss at high temperature. Ferroelectric characteristics can still be detected in Ba0.4Sr0.6Ti1−xZrxO3 ceramics and residual polarization (Pr) decreased with increasing Zr4+ content.

Bag-hose precipitation for its efficient, reliable, low energy consumption and simple maintenance has been widely recognized in various industries. The application of bag-hose precipitation in more than twenty fields presents rapid development trend, such as electric power, cement, steel, non-ferrous metals, machinery, chemical industry and municipal. The research status of bag-hose precipitation technology is reviewed. The application situation and developing trend in the electric power, cement, waste incineration and steel are summarized. The developing direction of high temperature filter materials in bag-hose precipitation is anticipated.

The thermal behaviors of enoxacin and its hydrochloride under inert conditions were investigated by TG, FTIR, and TG/DSC-FTIR. The results indicated that the thermal behavior of enoxacin can be divided into three stages, while its hydrochloride consisted of four stages. The main difference lay in the sequence of decarboxylation and decarbonylation. For the enoxacin, the decarboxylation and decarbonylation occurred simultaneously, but for its hydrochloride, the two processes occurred in turn. The reason for this was the existence of hydrochloric acid in enoxacin hydrochloride, which changed its intermolecular force. The thermal analysis kinetic calculations of their first two stages were carried out, respectively. The apparent activation energy, pre-exponential factor, and the most probable model function were obtained using the master plots method. The results indicated that all these stages can be described by the model of nucleation and nucleus growing.

The thermal behavior of nicotinic acid under inert conditions was investigated by TG, FTIR and TG/DSC-FTIR. The results of TG/DSC-FTIR and FTIR indicated that the thermal behavior of nicotinic acid can be divided into four stages: a solid-solid phase transition (176–198°C), the process of sublimation (198–232°C), melting (232–263°C) and evaporation (263–325°C) when experiment was performed at the heating rate of 20 K min−1. The thermal analysis kinetic calculation of the second stage (sublimation) and the fourth stage (evaporation) were carried out respectively. Heating rates of 1, 1.5, 2 and 3 K min−1 were used to determine the sublimation kinetics.

Thermal stability of horseradish peroxidase (HRP) was studied by differential scanning calorimetry, tryptophan fluorescence, the heme absorption and enzymatic activity analysis while the concentrations of sodium phosphate buffer ranged from 2.5 to 50 mM at pH 7.0. The results showed that the denaturation temperature (Tm) values decreased and the intrinsic tryptophan fluorescence intensity of denatured HRP increased as sodium phosphate buffer concentration increased. Furthermore, the heme absorbance at 403 nm and enzymatic activity of HRP decreased with the increasing buffer concentrations. According to data obtained in this experiment, it can be concluded that sodium phosphate accelerated the denaturation process of HRP and reduced the thermal stability of HRP.

An online-coupled TG–FTIR evolved gas analysis (EGA) instruments have been used to identify and monitor the evolution of gaseous products during the thermal decomposition of phenylalanine and tyrosine in flowing N 2 atmosphere up to 800 °C. The results indicate that the thermolysis processes of these two compounds are similar. For both of them the main primary decomposition steps are two competing paths: the direct decarboxylation and the concerted rupturing of C–C bonds. And the primary decomposition reactions also include deamination and dehydration. The main secondary reaction is the crack of cyclic dipeptide which also presents two competing pathways. The main gaseous products are NH 3 , H 2 O, CO 2 , CO, HNCO, HCN and some organic compounds. However, compared with tyrosine, the decomposition of phenylalanine is more complete and involves less secondary reaction. That is caused by their different thermal stability and decomposition temperature.