Jiaqiang Wang

Microwave sensor for measuring the properties of a liquid drop

A novel microwave sensor for measuring the properties of a liquid drop has been invented, its analytical theory established and a working prototype has been constructed and tested. It was also found that the theory based on the microwave sensor is in good agreement with the experimental results. Excellent linearity is achieved by optimizing the design, with an accuracy of distilled water drop volume measurement of approximately 0.5 µl, and this microwave sensor has been used to measure surface tension, species concentration and the microwave absorption properties of a liquid drop simultaneously, which are the key parameters in the fields of physical chemistry and microwave chemistry.

Study of the degradation of acetaldehyde by time-resolved microwave sensor (TRMS)

The degradation of acetaldehyde in the gas phase over Co-MCM-41, Ce-MCM-41 and MCM-41 under dark condition was studied by time-resolved microwave sensor (TRMS). Characteristic of the microwave cavity was simulated by commercial finite element software ANSYS, and the relation between reaction time and moisture content of the catalyst powder during the process of the acetaldehyde degradation was obtained. It showed that Co-MCM-41 is an efficient catalyst for acetaldehyde degradation under ambient, dark conditions. The experimental results of the TRMS were in good agreement with that of Fourier transform infrared spectroscopy (FTIR).

Detection of the Catalytic Processes by Time-Resolved Microwave Sensor

A novel time-resolved microwave sensor was developed to probing information of reaction kinetics, which is of fundamental importance for the understanding of the catalytic processes and the synthesis of catalyst. The processes of the decomposition of acetaldehyde on different catalysts (Cd/MCM-41, Ce/MCM-41, Co/MCM-41 and Ni/MCM-41) had been detected by the sensor, respectively. The results showed that it was possible to use time-resolved microwave sensor for probing the information of reaction kinetics.

Acquisition of Hydration States of Zinc Acetate Dihydrate and Aluminium Potassium Sulfate Dodecahydrate by Microwave Sensor

A novel microwave sensor was developed to acquire the information of various hydration states of salt hydrates, which is a key parameter in chemistry, metallurgy, mineralogy and geology. Various hydration states of zinc acetate dihydrate (Zn(CH₃COO)₃ldrxH₂O; x=2) and aluminium potassium sulfate dodecahydrate (KAl(SO₄)₂ldrxH₂O; x=12, 6) were detected by the microwave sensor, respectively. It was found that the results obtained by the sensor were in good agreement with those determined by TG and DTA. Besides the kinetics can be detected real-timely the microwave absorption properties during losing crystalline water of Zn(CH3COO)₃ldr2H₂O and KAl(SO₄)₂ldr12H₂O could also be detected by the microwave sensor.

Absorption Properties of Materials under Microwave Irradiation

The paper presents dielectric relaxation processes of materials that is a key physical phenomenon in the fields of microwave chemistry, microwave detection and microwave processing of materials. Using the new equation for the description of dielectric losses under microwave irradiation, which was developed by authors, absorption properties of rubber compounds was simulated. It was found that the simulating results based on this new equation are in good agreement with the Volge-Fulcher law. It shows that the new equation has potential application in the study of microwave interaction with materials.