RSC Advances Blog

By Sarah Brown, web writer for RSC Advances

Superhuman olfaction isn’t right up there on my list of desired super powers for a number of reasons that I won’t share here; however, an enhanced appreciation for the detection of various gases is underrated.

For example, the ability to detect toxic gases is of huge benefit, particularly at levels before they pose danger to humans. Electronic noses (E-noses) have been created from nanowire arrays as devices for sensing technology; however, most E-noses require operating temperatures of over 200 °C, which may be a limiting factor in their practical application.

Writing in RSC Advances, Chatchawal Wongchoosuk and co-workers describe the fabrication of a ZnO-based E-nose that operates at room temperature and can detect down to the ppb level. The ZnO nanowires were surface modified to include ZnO-ZnAl₂O₃ and ZnO-Zn₂TiO₄ core-shell nanowires, which formed electrical connections by self-assembly. Ultraviolet light, positioned above the sensors, was used to generate electron hole pairs and oxygen species, which, on reaction with a gas or gases could change the layer width of the nanowires and ultimately lead to the detection and characterisation of the substance.

The ability for the E-nose to operate sensitively at room temperature makes a lot of scents and these developments are not something to be sniffed at (groan!)

Read the full article by clicking the link below – free to access until 16th October:

Electronic nose for toxic gas detection based on photostimulated core–shell nanowires
Chatchawal Wongchoosuk, Kittitat Subannajui, Chunyu Wang, Yang Yang, Firat Güder, Teerakiat Kerdcharoen, Volker Cimalla and Margit Zacharias, RSC Adv., 2014, 4, 35084–35088, DOI: 10.1039/C4RA06143H

Sarah Brown is a guest web-writer for RSC Advances. Sarah hung up her lab coat after finishing her PhD and post-doctorate in nanotechnology for diagnostics and therapeutics and now works in academic publishing. When not trying to explain science through ridiculous analogies, you can often find her crocheting, baking or climbing, but not all at once.

Posted on behalf of Sarah Brown, web writer for RSC Advances

To state the obvious, Louis Braille was a bit of a legend. Taking an existing idea, developing and simplifying it, he enabled those with visual impairments another level of independence. What adds to his profile as genius is that he wasn’t even appreciated in his own time.

The Braille system was based on a system known as ‘night writing’ invented by the fabulously titled Captain Charles Barbiere la Sierre for soldiers to communicate in the dark without having to turn on a light or talk. This comprised 12 dots in six rows, formed by indents into the back of a surface to create patterns of raised dots that could be scanned by touch. Louis Braille stripped this back to the system that we now recognise, of up to six dots in three rows. Apparently Barbiere took the hump at this and Braille’s peers at the school for the blind where he taught were reluctant to take it up until after his death. I detect a hint of jealousy.

As Wongjin Jo and co-workers, authors of a paper recently published in RSC Advances, point out, characters in Braille generally come in only one font size, with no distinctions for titles or paragraph text. Furthermore, the characters can become more difficult to detect if repeatedly depressed. The recent surge in the capabilities of 3D printing can help overcome these limitations and more by adding the ‘dots’ to surfaces, rather than indenting them. Using a thermoplastic polymer, layers of dots can be added to generate characters of varying sizes and thicknesses on various surfaces, with the potential to offer visually impaired people the ability to add braille characters as they require and for the circumstances they personally encounter.

To protect the characters and improve their durability, the authors used a thermal reflow process to improve the surface smoothness and adhesion to the platform it was built on.

The flexibility of 3D printers and their expected drop in costs as they become more ubiquitous furthers the work of Louis Braille and opens the world up a little wider for those with visual impairments.

Interested in finding out more? Read the full article using the link below:

3D printed tactile pattern formation on paper with thermal reflow method, Wonjin Jo, Hyun Kim, Jeong Sim Lee, Jeon Ju Lee and Myoung-Woon Moon, RSC Advances, 2014, 4, 31764

Sarah Brown is a guest web-writer for RSC Advances. Sarah hung up her lab coat after finishing her PhD and post-doctorate in nanotechnology for diagnostics and therapeutics and now works in academic publishing. When not trying to explain science through ridiculous analogies, you can often find her crocheting, baking or climbing, but not all at once.

Scientists in Taiwan have put together a system that uses a computer screen and digital camera to obtain spatial, temporal and spectral information on reaction samples, with a set-up cost of just £400.

Pawel Urban who led the research at National Chiao Tung University, Taiwan, points out that ‘chemical processes occur in space and time, but few analytical methods provide both spatial and temporal information’. Most chemical reaction mixtures are also not homogeneous, but traditional spectral techniques for monitoring them assume homogeneity. Pawel believes it is important to look into the intrinsic non-uniformities which can affect the progress of chemical reactions

Read the full article in Chemistry World»

Read the original journal article in RSC Advances – it’s free to access until 10th September:
Spectral imaging of chemical reactions using a computer display and a digital camera
Kai-Ta Hsieh and Pawel L. Urban  
RSC Adv., 2014, 4, 31094-31100, DOI: 10.1039/C4RA04207G

Scientists in Spain have developed a new material that changes colour around air- or waterborne TNT. The chemical, which could be used to make intelligent clothing, alerts users to the presence of the explosive. It may prove lifesaving in former war zones, and invaluable in anti-terrorism investigations.

Read the full article in Chemistry World»

Read the original journal article in RSC Advances – it’s free to access until 1st August:
Involuntary graphene intake with food and medicine
Manav Saxena and Sabyasachi Sarkar  
RSC Adv., 2014, Accepted Manuscript, DOI: 10.1039/C4RA04022H, Paper