[Comparison of two types of T-shaped coronectomy applied in extraction of impacted mandibular third molars].

Purpose: To compare the clinical efficiency of two types of T-shaped coronectomy applied in extraction of impacted mandibular third molars. METHODS：One hundred and twenty patients meeting with the criteria were randomly divided into 2 groups. Two types of T-shaped coronectomy were applied in extraction of impacted mandibular third molars.

[Diagonal root separation method for extracting impacted double-root mandibular third molars].

Double-root mandibular third molars are the common types of mandibular third molars that are prone to impac-tion. Based on the summary of clinical cases and experience, the commonly used crown-root separation technique is improved as diagonal root separation technique that divides the roots by the line connecting the distal axis angle to the root furcation. This new method improves the efficiency of the operation and reduces surgical trauma.

[CoCuMnOx Photocatalyzed Oxidation of Multi-component VOCs and Kinetic Analysis].

Solar energy absorption coating CoCuMnOx was prepared by co-precipitation method and applied to photodegrade multi- component VOCs including toluene, ethyl acetate and acetone under visible light irradiation. The photocatalytic oxidation performance of toluene, ethyl acetate and acetone was analyzed and reaction kinetics of VOCs were investigated synchronously. The research indicated that removal rates of single-component toluene, ethyl acetate and acetone were 57%, 62% and 58% respectively under conditions of 400 mg · m⁻³ initial concentration, 120 mm illumination distance, 1 g/350 cm² dosage of CoCuMnOx and 6 h of irradiation time by 100 W tungsten halogen lamp.

[Microwave In-situ Regeneration of Cu-Mn-Ce/ZSM Catalyst Adsorbed Toluene and Distribution of Bed Temperature].

Microwave in-situ regeneration of Cu-Mn-Ce/ZSM catalyst adsorbed toluene, distribution of fixed bed temperature, adsorption breakthrough curves of the catalyst after several regenerations and characterizations of the catalyst by BET and SEM were investigated in this study. The research indicated that regeneration effect of the catalyst adsorbed was excellent under conditions of microwave power 117 W, air flow 0.5 m3 x h(-1) and catalyst dosage of 800 g.

[Catalytic oxidation of two-component VOCs and kinetic analysis ].

Catalytic oxidations of two-component volatile organic compounds (VOCs) toluene and chlorobenzene were investigated under microwave heating and tube furnace heating, respectively, and reaction kinetics were analyzed in this paper. The research indicated that competitive adsorption between toluene and chlorobenzene reduced their removal efficiencies by 3% -12% as compared to single component. 'Hot spot effect' and 'non-thermal effect' under microwave irradiation obviously enhanced conversion efficiencies of VOCs, especially, the chlorobenzene removal was increased by 31% -38%.

[Synergetic effects of silicon carbide and molecular sieve loaded catalyst on microwave assisted catalytic oxidation of toluene].

Molecular sieve loaded catalyst was prepared by impregnation method, microwave-absorbing material silicon carbide and the catalyst were investigated for catalytic oxidation of toluene by microwave irradiation. Research work examined effects of silicon carbide and molecular sieve loading Cu-V catalyst's mixture ratio as well as mixed approach changes on degradation of toluene, and characteristics of catalyst were measured through scanning electron microscope, specific surface area test and X-ray diffraction analysis. The result showed that the fixed bed reactor had advantages of both thermal storage property and low-temperature catalytic oxidation when 20% silicon carbide was filled at the bottom of the reactor, and this could effectively improve the utilization of microwave energy as well as catalytic oxidation efficiency of toluene.

[Study on catalytic oxidation of benzene by microwave heating].

The performance in catalytic oxidation of benzene was investigated in two different heating modes, microwave heating and conventional electric furnace heating. The effects of copper (Cu)-manganese (Mn) mass ratio, doping dose of cerium (Ce) and calcination temperature on the catalytic activity of Cu-Mn-Ce/molecular sieve catalyst were also checked in catalytic oxidation of benzene with microwave heating, and the catalysts were subsequently characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The results showed that the catalyst had better catalytic activity for the oxidation of benzene under microwave heating than electric furnace heating, and high oxidation efficiency for benzene was reached due to the "local hot spots" and dipole polarization effect of microwave and stable bed reaction temperature.