The problem of cleanmindedness among secondary pupils and some of the factors and methods involved in moral guidance

Not Available.Benj. H. WibbelerNot ListedNot ListedMaster of ScienceDepartment Not ListedCunningham Memorial library, Terre Haute, Indiana State University.isua-thesis-1929-wibbelerMastersTitle from document title page. Document formatted into pages: contains 106p. : ill. Includes bibliography

Vibrationsverdichtung von hartmagnetischen Pulvern im Magnetfeld Schlussbericht

The excitation of vibrations in bulk material can increase the mobility of the powder particles in a powder bed. This project was dedicated to investigations of the possibilities of improving the orientation of magnetic fields through vibratory compaction of magnetically hard powders in the magnetic field. The magnetic powders (Nd, Fe, B and Sr ferrite powders) were filled into the die with/out pressing aids while maintaining vibrations (f = 100 - 1000 Hz, a = 5 - 25 g) and an external magnetic field (H _m_a_x = 330 kA/m). After precompaction by filling (t = ca. 15 sec) a specific load was applied to the powder for vibratory compaction (p _m_a_x = 13.2 MPa). The results obtained for Nd, Fe, B powders showed that pressing aids such as natural rubber have a negative effect on the magnetic properties. Without pressing aids the dimensional stability of the green compact is insufficient. The vibratory compaction of Sr ferrite powders showed that moisture combined with PVA additives suppress the effect of orientation through agglomeration and that vibratory compaction in the absence of moisture results in a remarkable magnetic field orientation. (orig.)SIGLEAvailable from TIB Hannover: F94B1152+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman