Development of a new coated electrode with low nickel content for welding ductile iron and its response to austempering

Coated Electrodes with small amounts of nickel were developed for welding ductile iron (DI) and conversion of the same into austempered ductile iron (ADI) after austempering. Among six electrodes, Trials 3 and 4 were selected for establishing crack-free weld deposits via preheating and post-weld heat treatment. Austenitization was performed at 900℃ for 2 h and austempering at 300 or 350℃ for three different holding times to observe the results of austempering with respect to the microstructure, hardness, and austempering kinetics of the samples. The microstructures of the weld deposits showed needle-like bainitic ferrite with small amounts of retained austenite when treated at 300℃ and feathery bainitic ferrite with large amounts of retainedaustenite when treated at 350℃. The electrode labeled with Trial 3 revealed greater austenite contents than that labeled with Trial 4 when treated with a 2 h holding time regardless of the austempering temperature applied. The transformation rate of the bainitic ferrite of Trial 3 was relatively higher than that of Trial 4 and showed a lower rate constant, leading to a higher diffusion rate of carbon in austenite.     

Electron diffraction of the metallic elements in the pineal organ of a freshwater fish, Mystus vittatus (Bloch.)

By electron diffraction pattern the presence of metallic elements, particularly chromium-nickel, chromium phosphide, copper, aluminum-copper and zinc has been shown in the pineal organ of a freshwater teleost, M. vittatus. It is likely that their occurrence within the pineal is due to binding with the neurosecretory material fractions/ligands.     

Histochemical localization of acetylcholinesterase in the glycogen body (sinus rhomboidalis) of common brown dove,Streptopelia senegalensis and house sparrow,Passer domesticus

Summary Acetylcholinesterase (AChE) activity was studied in the glycogen bodies of the spinal cords of 2 birds namelyStreptopelia senegalensis andPasser domesticus. A possible functional significance of AChE in the light of relative enzymatic localization especially in Hoffmann-Kolliker nuclei (motor cell groups), substantia gelatinosa and other regions of gray matter of 2 avian glycogen bodies has been discussed.     

A possible role of guanine-deaminase inhibitor

Zusammenfassung Diskussion über die Frage der Ätiologic der Xanthinurie.     

Photo-induced optical changes in GexAs40Se60-x thin films

Ge-As-Se chalcogenide thin films show a wide range of photosensitivity, which is utilized for the fabrication of micro-optical elements for integrated optics. The photosensitivity of GexAs40Se60?x(x=0,15) chalcogenide thin films for UV light was presented. For that purpose, the bulk samples of GexAs40Se60?x(x=0,15) chalcogenide glasses were prepared using conventional melt quenching technique, and thin films were prepared using thermal evaporation technique. These thin films were exposed to UV light for two hours. Amorphous natures of bulk samples and thin films were verified by XRD and chemical compositions were verified by EDX measurements. The thicknesses of the thin films were measured using a thickness profilometer. Linear optical analysis of these thin films was done using transmission spectra in wavelength range of 300?900 nm. Optical bandgap was determined by first peak of transmission derivative as well as extrapol ation of Tauc’s plot. R2 analysis was done using R software to ensure that the material is indirect bandgap material. It is observed that two hours UV exposure causes photo-darkening along with photo-expansion in As40Se60 thin films, while photo-bleach ing and photo-densification for Ge15As40Se45 thin films. However, the amounts of photo-induced optical changes for Ge15As40Se45 thin films are smaller than those for As40Se60 thin films. The changes in optical absorption, bandgap and thickness are understood base d on the bonding rearrangement caused by UV exposure.     

Interruption of acoustic communication and mating in a leafhopper and a planthopper by aerial sound vibrations picked up by plants

Summary Each sex of the cotton leafhopper and the rice brown planthopper communicates with the opposite sex by certain specific sound vibrations which travel through the plant surface and lead to mating. External sounds of certain frequencies, viz., 200 c/sec, generated by a harmonium or an audio-oscillator are picked up from the air by the plants and interrupt the acoustic communication as well as mating of the insects. Notes with harmonics are effective whereas pure notes are ineffective.The authors gratefully acknowledge P.L. 480 grant No. FG-IN-551 from the US Department of Agriculture for project No. IN-ARS-90, under which this work was carried out.     

Differential implantation of twin blastocysts inMegaderma (Microchiroptera)

Zusammenfassung Ungleichgeschlechtige Zwillinge von verschiedener Grösse vonMegaderma lyra lyra (Microchiroptera) wurden im April letzten Jahres in einem trächtigen Weibchen gefunden. Um die Grössendifferenz der Zwillinge zu erklären, wird angenommen, dass in diesem Falle zwei Eier befruchtet worden waren, dass die linke Zygote einen Vorsprung über die rechte gewann und dass deshalb dic Implantation der rechten Blastocyste verzögert wurde.