Electroforming Copper Feedhorns Using Aluminum Mandrels

Chemistry, Technology
[caption id="attachment_24084" align="alignright" width="480"] Copper electroforming bath, with growing electroforms and bagged anodes. Pump and continuous bath filtration are essential, though they are not shown for clarity.[/caption] The electroplating laboratory technician may be asked to grow a metal object from scratch, rather than merely plate an existing part. The result, before final external machining, is called an electroform. Electroforming involves much more than merely plating a long time. Critical issues need to be addressed to ensure success. While electroforming involves science, it is truly an art. Definitions and Basics [caption id="attachment_24085" align="alignleft" width="300"] A microwave feedhorn is similar to an old-fashioned ear trumpet. Image National Archives.[/caption] Microwaves are electromagnetic waves with a wavelength in the range of 0.001–0.3 meters. When creating a microwave feedhorn via electroforming, the scientist will grow…
Read More

Imidazole Synthesis and Chemistry

Biology, Chemistry
Imidazole is an aromatic 5-member ring organic compound containing two skeletal atoms other than carbon. Both of those are nitrogen. One of the molecule's resonance structures, if it actually existed, would contain a secondary amine group (-NH-), an imine group (=N-), and an alkene group (-C=C-). The other resonance structure would contain two imine groups and a methylene group (-CHβ‚‚-). Those structures are drawn below. However, imidazole doesn't act like either of them. This is typical for aromatic compounds. We will briefly discuss the ring's synthesis and chemistry. Synthesis Imidazole is formed by reacting glyoxal with formaldehyde in the presence of ammonium acetate in acetic acid. The driving energy is microwave radiation. More generally, this reaction is used to produce substituted imidazoles. The basic reaction, however, is written, OHC-CHO +…
Read More