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CsPbX 3 (X = Cl, Br, I) perovskite quantum dots (QDs) have emerged as competitive candidate luminescent materials in the photoelectric fields due to their superior luminescence properties. However, the major drawback such as poor resistance to temperature, moisture, and irradiation of light, especially for the red QDs with I - , hinders their practical applications. Herein, we synthesized Mn 2+ -doped CsPbCl 3 embedded in the cage of zeolite-Y as a new orange-red phosphor for the white light-emitting diode (WLED). The composites have significantly improved resistance to both elevated temperature and water over the bare Mn 2+ -doped QDs. The former exhibits little degradation whereas the latter shows apparent decline upon the irradiation of lights in the orange LED devices, which are fabricated by employing each material as a color-conversion phosphor coated on a 365 nm UV chip. A WLED is also achieved with a 365 nm UV chip coated with a CsPb(Cl 0.5 ,Br 0.5 ) 3 -Y blue phosphor and a CsPb 0.75 Mn 0.25 Cl 3 -Y orange phosphor. The device possesses a Commission Internationale de l'Éclairage coordinate of (0.34, 0.36), a correlated color temperature of 5336 K and a color rendering index of 81.

The plasmas generated by dielectric barrier discharge in atmospheric pressure air have wide application prospect in industry. In order to study generation condition and mechanism, the dielectric barrier uniform discharge in atmospheric pressure air has been studied experimentally with a micro-gap discharge device. Results of electrical characteristics indicate that it exist several current pulses with short width in half period of the applied voltage at a low voltage, a large number of micro-discharge filaments are observed. The discharge power increases with increasing peak value of applied voltage, the micro-discharge filaments increase meanwhile. When the peak of applied voltage reaches to 9.2 kV, only a discharge hump with a width of about 5.5 μs appears in a half period of the applied voltage, micro-discharge filaments cannot be discerned. The uniform discharge has been obtained finally as the micro-discharge filaments extend and superimpose randomly. The emission spectrum of dielectric barrier discharge scanning from 330 to 420 nm is collected. It is found that the intensity of 337.1 nm is stronger than that of 391.4 nm. If the intensity of 337.1 nm is considered as the datum reference, the intensity of 391.4 nm shows the magnitude of electron average energy. The molecule internal energy is evaluated by vibration temperature. The electron average energy and molecule internal energy have been investigated by optical emission spectra. It is found that both of them decrease with increasing the applied voltage. Results indicate that it is not easy to form filamentary discharge when the electrical energy is lower. The average electron energy of uniform discharge is lower than that of the filamentary discharge. These results are of great significance to the application of dielectric barrier uniform discharge obtained in air at atmospheric pressure.

In order to enhance the efficiency of anaerobic digestion, the effects of ultrasonic pretreatment, alkaline pretreatment and the combination of these two methods have been studied on sludge disintegration by using multifrequency ultrasonic batch. The results showed that the combining of ultrasonic and alkaline treatment was more effective than alkaline or ultrasonic treatment alone in releasing SCOD and VSS solubilization. The VSS reduction rate was 15.98% with ultrasonic pretreatment alone, 22.12% with alkaline pretreatment alone(NaOH/TS = 0.04). When the sludge was pretreated by the alkaline treatment (NaOH/TS = 0.04) for 24 h followed by ultrasonic vibration for 60 min, and simultaneous ultrasonic (60 min) and alkaline( NaOH/TS = 0.04) treatment, the VSS reduction rate could reach 51.45% and 54.45% respectively. Two distinct phases of hydrolysis were observed. The first phase was a very rapid increase in solubilization, followed by a much slower second phase. According to kinetic analysis for first rapid phase, the simultaneous alkaline and ultrasonic treatment could not only get the highest hydrolysis rate among these methods, but also reduce the pretreatment time in ultrasonic pretreatment and alkaline dose in alkaline treatment.