See if you can find the 8 differences in each set of images.
Superconducting city
This optical profilometer image shows ink-jet printed micrometer-scale tracks of YBa2Cu3Ox superconductor. The ink used is an aqueous solution containing Cu, Ba, and Y ions. The “printing” is followed by a thermal treatment. The molecular structures are examples of how Cu ions in the ink are stabilized by triethanolamine (TEA) molecules.
Petra Lommens, Ghent University, Belgium
![](https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary-alt:20160712023338-12042-mediumThumb-S0883769413001474_figu1g.jpg?pub-status=live)
Dendritic baby giraffe
This scanning electron microscope image depicts a baby giraffe formed within a jungle of Ni-Al-C dendrites. As the molten alloy was being solidified inside a graphitic crucible, the melt was decanted, leaving behind a little dendrite wetted by a thin molten blanket. As the dendritic jungle got colder, the blanket froze and rejected carbon, which eventually crystallized as a graphite cover. Upon further cooling, the graphitic cover wrinkled, due to its thermal expansion coefficient mismatch with the metallic substrate, creating a faceted network of creases resembling the skin patches of a giraffe.
Shaahin Amini, University of California–Riverside, USA
![](https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary-alt:20160712023338-09270-mediumThumb-S0883769413001474_figu2g.jpg?pub-status=live)
The answers will be in the August 2013 issue.
![](https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary-alt:20160712023338-32494-mediumThumb-S0883769413001474_figu3g.jpg?pub-status=live)