The potential for material processing by microwave energy
This paper presents the potential applications for material processing by microwave energy which is electromagnetic waves that penetrates material and cause its molecules to rotate and generate heat. In this paper, potential uses of microwave energy in iron and steel making processes will be discussed in detail. Actually, microwave energy has been in use for various applications for over half century. One of the most well known applications is drying and cooking of food. Currently, industrial uses of microwave energy include direct-reduced iron making, wood processing, sintering, coke making, and so on. And moreover, CO2 and CH4 can be decomposed by super heating effect of microwave energy which can also be called as high temperature plasma furnace. In conventional heating processes, the materialpsilas surface is heated first and then the heat moves inward, while the material is heated the entire volume at about the same time, in microwave heating processes. Microwave heating method can be used in addition to conventional heating techniques to enhance the reaction of the material processing.
Decompositions of Carbon Dioxide, Carbon Monoxide and Gaseous Water by Microwave Discharge
Conditions for the effective decompositions of CO2, CO and H2 0(g) in microwave discharge (20–100 W) were studied in a flow method, in connection with fixation of 14C (in CO2). Carbon dioxide of 0.41 to 1.34 kPa was decomposed into CO in 73–92% yield in the linear gas velocity range of 0.01 to 0.56 m/s (the residence time in plasma, 4.50 to 0.08 s). For 0.83 kPa CO2, the maximum value of 92% was obtained at 0.04 to 0.06 m/s, and further increase in the linear gas velocity to 0.56 m/s decreased the yield to about 80%. Only 5% or less of CO (0.82 kPa) was converted to carbon under the same condition as above. Almost 100% of H20(g) of 0.82 kPa was decomposed into H2 and O2 at 0.60 m/s (the residence time, 0.08 s) and 50 W. The effective decomposition of H2 0(g) needs such a high linear gas velocity to suppress the reverse reaction. The use of the appropriate linear-gas-velocity is important for the effective decompositions of CO2 and H2 0(g). The reaction of H2 with O2 to form H2O proceeds at temperature as low as 293 K on SUS and Cu metal surfaces; this phenomenon was applied to analysis of the decomposition of H2O(g).
Adolescent sexual offenders: incidence of childhood maltreatment, serious emotional disturbance, and prior offenses.
Adolescents incarcerated for sexual offenses were compared to those incarcerated for other crimes on measures of prior child abuse and neglect, serious emotional disturbance, and involvement in child welfare and the juvenile justice system. Sexual or physical abuse was more common than neglect among sexual offenders with fewer than three prior maltreatment reports. Sexual offenders were twice as likely to be receiving special education services for severe emotional disturbance, and were usually incarcerated later than other offenders. Implications for research and practice are discussed.