Manganese-doped zinc silicate powder samples were prepared successfully by solution combustion process,and their photoluminescence were investigated in ultraviolet region. The single-phase of Zn_(2- x )SiO_4: x Mn (0...Manganese-doped zinc silicate powder samples were prepared successfully by solution combustion process,and their photoluminescence were investigated in ultraviolet region. The single-phase of Zn_(2- x )SiO_4: x Mn (0≤ x ≤0.10,willemite) was obtained by combustion synthesis at 600 ℃ for afew minutes,then heat treated at above 900 ℃ for 4 h. In the excitation spectra of Zn_(2- x )SiO_4: x Mn (0< x ≤0.10),the strongest broad band at about 254 nm is observed and assigned to (() 6A_1)→(() 4T_1) transition of Mn (2+) monitoring at 525 nm emission. At about 525 nm,the intense broad band emission is observed under 254 nm excitation in Zn_(2- x )SiO_4: x Mn (0< x ≤0.10). This broad band is attributed to (() 4T_1)→(() 6A_1) transition of Mn (2+). The results indicate that photoluminescence efficiency,the location of the strongest excitation or emission band,and the optimum concentration of activator depend on starting materials,combustion temperatures,the dosage of fuels,and the size of powder samples etc..展开更多
Through a lot of experiments, a new kind of stove using horizontal combustion tech-nique for bituminous coal briquet has been developed. Making use of this stove, studies have been made on burning process of bituminou...Through a lot of experiments, a new kind of stove using horizontal combustion tech-nique for bituminous coal briquet has been developed. Making use of this stove, studies have been made on burning process of bituminous coal briquet, distribution of temperature field in the stove, the regularities of evolution and combustion of volatile matter, the burning rate and edi-ciency of bituminous coal briquet, characteristics of fire-sealing and sulfur-retention. The results show that, with the technique, some achievements can be obtained in combustion of bituminous coal briquet, such as lower pollution that the flue gas black degree is below 0. 5R and dust con-centration is below 90 mg/m3. The stove’s combustion efficiency reaches 90%, sulfur fixing effi-ciency is 60%, and oO concentration is decreased by 40% compared with other traditional stoves. With so many advantages, the stove can be used extensively in civil stoves and smaller industrial boilers.展开更多
In combination with low NOX combustion techniques inChina and in view of limits of the Standard of Discharging Atmo-spheric Pollutants from Thermal Power Plants to be published soon,this paper presents corresponding t...In combination with low NOX combustion techniques inChina and in view of limits of the Standard of Discharging Atmo-spheric Pollutants from Thermal Power Plants to be published soon,this paper presents corresponding technical countermeasures andkey subjects to be studied.展开更多
文摘Manganese-doped zinc silicate powder samples were prepared successfully by solution combustion process,and their photoluminescence were investigated in ultraviolet region. The single-phase of Zn_(2- x )SiO_4: x Mn (0≤ x ≤0.10,willemite) was obtained by combustion synthesis at 600 ℃ for afew minutes,then heat treated at above 900 ℃ for 4 h. In the excitation spectra of Zn_(2- x )SiO_4: x Mn (0< x ≤0.10),the strongest broad band at about 254 nm is observed and assigned to (() 6A_1)→(() 4T_1) transition of Mn (2+) monitoring at 525 nm emission. At about 525 nm,the intense broad band emission is observed under 254 nm excitation in Zn_(2- x )SiO_4: x Mn (0< x ≤0.10). This broad band is attributed to (() 4T_1)→(() 6A_1) transition of Mn (2+). The results indicate that photoluminescence efficiency,the location of the strongest excitation or emission band,and the optimum concentration of activator depend on starting materials,combustion temperatures,the dosage of fuels,and the size of powder samples etc..
文摘Through a lot of experiments, a new kind of stove using horizontal combustion tech-nique for bituminous coal briquet has been developed. Making use of this stove, studies have been made on burning process of bituminous coal briquet, distribution of temperature field in the stove, the regularities of evolution and combustion of volatile matter, the burning rate and edi-ciency of bituminous coal briquet, characteristics of fire-sealing and sulfur-retention. The results show that, with the technique, some achievements can be obtained in combustion of bituminous coal briquet, such as lower pollution that the flue gas black degree is below 0. 5R and dust con-centration is below 90 mg/m3. The stove’s combustion efficiency reaches 90%, sulfur fixing effi-ciency is 60%, and oO concentration is decreased by 40% compared with other traditional stoves. With so many advantages, the stove can be used extensively in civil stoves and smaller industrial boilers.
文摘In combination with low NOX combustion techniques inChina and in view of limits of the Standard of Discharging Atmo-spheric Pollutants from Thermal Power Plants to be published soon,this paper presents corresponding technical countermeasures andkey subjects to be studied.
