Aligning Forces on Wood Particles in an Electric Field

Electrostatic alignment affords a promising route to improved mechanical properties in anisotropic particleboards aimed at competition with sawn lumber in structural uses. A quartz-fiber torque balance was used to measure the aligning torque exerted on elongated wood particles by DC and AC fields over a range of wood moisture content, field intensity, and frequency. Approximate predicting equations relating aligning torque to relevant process parameters have been developed, which should aid the process designer. The dynamics of free-falling particles in an electric field favors small slender particles and high field intensity for best alignment. However, slender particles have long charge relaxation times and thus require high moisture content for effective alignment in a field of a given frequency

Effect of Iodine on Mercury Concentrations in Dental-unit Wastewater

Dental amalgam is a mixture of mercury, silver, tin, and copper. Mercury typically makes up about 50% of it. The amalgam is used to provide the dental patient with a strong durable filling. Some of the dental amalgam may end up in the dental wastewater along with the water used for rinsing. Iodine is often used to control bacteria in dental-unit fresh waterlines. Could Iodine effect mercury concentrations in the wastewater?ISTC partnered with researchers at the Naval Institute for Dental and Biomedical Research to answer that question. Full results appear in Stone, Mark E., et al (2006). "Effect of Iodine on Mercury Concentrations in Dental-unit Wastewater." Dental Materials 22(2), 119-124. https://doi.org/10.1016/j.dental.2005.04.009.Ope

The Development and Validation of the Ethical Climate Index for Middle and High Schools

One school characteristic that needs to be considered as important in keeping schools safe is school climate. The purposes of this study were to develop and validate an instrument that measures the ethical climate of middle and high schools. To create the School Ethical Climate Index (SECI), we adapted the Ethical Climate Index for graduate and professional school programs to apply to middle and high schools. The SECI measures a school’s sense of community by assessing student and teacher interactions and relationships through the application of five ethical principles: respect for autonomy, nonmaleficence, beneficence, justice, and fidelity. To provide evidence of the SECI’s reliability and validity, we distributed the SECI to 101 teachers and administrators who worked at middle and/or high schools. The reliability coefficients for each of the SECI subscales were greater than .80. Differences between middle and high school teacher and administrator perceptions provided evidence of construct validity. The SECI could be used in school districts to assess areas for school improvement and, thereby, help to reduce school disorder and violence