New Worlds: New data from old books

Weizmann Institute researchers have found that some of the history preserved in old books and newspapers may be hiding between the lines.

By JUDY SIEGEL-ITZKOVICH
Everyone knows the rings of a felled tree can tell a lot about the local history and climate over decades and even centuries. Now, Weizmann Institute researchers have found that some of the history preserved in old books and newspapers may be hiding between the lines. Analyzing the carbon isotopes in bits of paper uncovers a record of atmospheric conditions at the time the trees were growing, says chemistry Prof. Dan Yakir of the Rehovot institute’s environmental sciences and energy research department, who has traced the effects of atmospheric pollution from burning fossil fuel going back to the Industrial Revolution. His project has been ongoing for about 14 years. The technique showed up differences between US and European records, and could be used to authenticate antique paper.
Scientists generally reconstruct the record of past climate change from ice cores or tree rings. But a reliable tree-ring history, says Yakir, requires the analysis of quite a few trees.
“Rather than going to forests all over the world to sample trees,” says Yakir, “we just went to the local library.” In the Weizmann archives, Yakir found issues of Science, Nature and the Journal of the Royal Chemical Society going back over 100 years. Removing small samples from successive volumes, he took them back to the lab for analysis, which was based on a finding that the proportion of a carbon isotope – carbon 13 (13C) – to its lighter counterpart – carbon 12 (12C) – could provide information on the CO2 added to the atmosphere from burning fossil fuel. All plants prefer to use CO2 made with the more common version of carbon, 12C, than the slightly heavier 13C.
Plant biomass from millions of years ago was transformed into reservoirs of oil, gas and coal, and so these are naturally low in 13C. “When we started to burn those reservoirs following the industrial revolution, we began returning the 13C-poor CO2 to the atmosphere. Now the atmospheric 13C content has become increasingly diluted, and this is reflected in the carbon ratios of trees milled for pulp and paper,” he explains. Yakir’s work shows that this continuing dilution is, indeed, clearly recorded in the archival paper and, plotted over time, it demonstrates the increasing intensity of our fossil fuel burning in the past 150 years.”
THE FUTURE OF PRINTED ELECTRONICS
Printing is not just to produce books, newspapers and package labels. The technology can also be used for the exciting fields of printed electronics – the ability to print electric circuits on almost any surface, including paper, plastic, silicon and ceramics. Printed electronics is already being used and being considered for use in multiple applications, including displays and thin-film photovoltaics, radio frequency identification (RFID) tags, organic light-emitting diode (OLED) lighting and sensors.
Now the Hebrew University’s technology transfer company Yissum Research Development and Vaxan Steel of Korea have signed a licensing and research agreement for the development of silver nanoparticles and silvercoated copper nanoparticles for conductive inks.
These inks can be utilized in a variety of printing technologies, including inkjet printing.The novel conductive inks were invented by Prof. Shlomo Magdassi, Dr. Alexander Kamyshny and Michael Grouchko from HU’s Institute of Chemistry. According to the terms of the agreement, Yissum grants Vaxan a license to commercialize the technology exclusively in Asia, excluding Israel and former Soviet Union countries, and will receive in return research fees and royalties from future sales.
Printing for the electronics industry is traditionally achieved by lithography and screen-printing technologies. But these methods are usually time consuming and expensive. In this technology, droplets of ink containing metallic nanoparticles are jetted from a micron-sized orifice onto the substrate, which can be a plastic sheet, glass or a silicon wafer.
“We are proud that the Hebrew University has had the opportunity to take part in this collaboration, and hope to strengthen our ties with the Korean industry in the future,” said Yissum CEO Yaacov Michlin. “We are confident that our new partners will help us in introducing this invention to the market.” Vaxan CEO Duek Chi Lee added: “The nanotechnology application we have licensed from Yissum will be applied to semiconductors, IT, LED, and OLED industries.
“ We are certain this technological innovation will be an international success in electronic markets of the future.