Vol. 3 No. 4 (1965)

Ichtisar. Dalam penjelidikan mengenai karakteristik suatu arrester, selain mengetahui karakteristik tembus terhadap tegangan pulsa djuga perlu diselidiki sifat2 tahanan non linearnja (lazim dipergunakan Si C) terhadap pulsa arus menentukan tegangan tinggalnja (Rest spanning). Untuk kepentingan ini dipergunakan pulsa arus 5 x 10 μ sec ataupun 10 x 20 μ sec. Disini akan dibahas mengenai parameter2 rangkaian dan faktor2 jang penting diperhatikan dalam perentjanaan suatu generator pulsa arus. Abstract. In order to obtain the performance characteristic of an arrester, besides knowing the…

. The reaction of zinc with methylene blue and thiocyanate is developed to a highly sensitive spectrophotometric determination of zinc in which the unknown zinc is reacted with methylene blue and thicyanate, giving insoluble complex. This is filtered off and the decrease in the amount of zinc present, is measured. Suitable masking agents prevent interference of most common ions, even when present in large amounts, except with cobalt, copper, cadmium and mercury which do not interfere if present in small amounts only. In simplicity, sensitivity and freedom from interference this method…

. Single crystals of 6061 alumunium alloy can be produced by "strain anneal" method from wire of 2mm diameter. With this method 70% of the test specimens grown into single crystals of length of 2.5 cm. Ichtisar. Kristal tunggal dari paduan aluminium 6061 dapat dihasilkan dengan tjara "strain anneal" dari kawat jang berdiameter 2 mm. Dengan tjara ini 70% dari kawat-kawat tersebut tumbuh mendjadi kristal tunggal jang pandjangnja 2,5 cm.

. Magnitudes and colours on the B, V system are determined for stars in the galactic cluster NGC 6124, based on a photoelectric sequence measured by Koelbloed and an extension of this toward faint stars. The distance of the cluster is about 580 pcs. and the age somewhat more than 108 years. Ichtisar. Magnitudo dan warna dalam sistim B. V daripada bintang2 dalam gugus galaktik NGC 6124 telah ditentukan berdasarkan suatu deret photoelektrik jang diukur oleh Koelbloed dan perluasannja kepada bintang-bintang jang lemah tjahanja. Djarak daripada gugus itu telah ditentukan kira2 580 pc. dan usianja…