Search | Sitemap | Intranet | PhD Intranet
 
spacer
spacer
  Home | About us | Research | Calendar | Publications | Training | Library | Contact  
  General | Working papers | Briefs | Books | I&T Weekly | RSS & E-zines | Archive  
 
 

Subscribe to I&T Weekly
A free e-zine about Innovation & Technology developments

text
html


Please type the above code:
rss feed RSS feed
 

Previous Issues I&T Weekly

>> back to archive

Previous issues of I&T Weekly:

2013: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17]
2012: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37]
2011: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42] [43] [44]
2010: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42]
2009: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42]
2008: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41]
2007: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40]
2006: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42] [43] [44]
2005: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40]
2004: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42] [43]
2003: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42] [43] [44] [45] [46] [47]
2002: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [40] [41] [42] [43] [44] [45] [46] [47]
2001: [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19]

 
         
 


 
Issue no. 21, 2007
Published: Jun 22, 2007

Developing nations embrace renewable energy
Power-generating buoys shelter in the deep
Ionic liquid offers greener recycling of plastics
Better biofuel uses best of both worlds
Researchers show off sugar cube sized fuel cell
'NanoSQUIDs' to improve magnetic microscopes
Developing nations embrace renewable energy
Developing countries have increased investment in renewable energy, accounting for one-fifth of the world's total last year, according to a report by the United Nations Environment Program (UNEP). The report states that investment in developing countries rose from 15% in 2004 to 21% in 2006. The increase happened largely in Brazil, China and India with significant funding of solar, wind and biofuel sectors.

Nine per cent of the investment occurred in China last year alone, with wind, biomass and waste sectors the most dynamic. India came second behind China but was the largest buyer of renewable energy companies abroad in 2006, the report says. But sub-Saharan Africa still lagged behind other regions in investment.

The UNEP report states that the world's total investment in sustainable energy climbed from USD 80bn in 2005 to a record USD 100bn last year - with research and development in the field rising by 25% to USD 16.3bn. It also reflects the scale of investment just 2% of the world's energy comes from renewable sources, yet renewables have captured 18% of the world's investment in energy generation. Small-scale projects, such as solar roof panels and micro turbines, are attracting increasing interest partly from growing opportunities in developing countries.
SciDev    Jun 21, 2007 back to top

Power-generating buoys shelter in the deep
AWS Ocean Energy has developed an underwater buoy that harnesses wave energy from 50 metres below the surface. The British company says that because the entire device is underwater, it does not suffer from storms in the way that other wave-power devices do, and will not interfere with shipping. It will be anchoring its first five test buoys to the seabed in a test site off the Scottish coast next year.

AWS's buoys, which is made from the same materials that are used in the underwater sections of oil rigs, sits in the calm of deeper waters. It harnesses wave energy at a distance, through the changes in pressure that waves generate by increasing and decreasing the water column.

The buoys are hollow and filled with a compressible gas that allows the top half of the buoy to move up and down. When a wave passes over them at the surface, the additional water stacked on top of the buoy increases the local water pressure, and the upper half of the device is pushed down. Between waves, the water column is shorter, the pressure lower, and the upper-half rises. This wave-driven pump action is converted into electricity, which can be fed into the national grid.
New Scientist    Jun 14, 2007 back to top

Ionic liquid offers greener recycling of plastics
A way of dissolving hard-to-recycle plastics like nylon and Kevlar back to their chemical building blocks has been demonstrated by researchers at Yamaguchi University in Ube, Japan. The team thinks refinements to the process could provide a new way to completely recycle such thermosetting plastics.

Plastics are already recycled less often than materials like cardboard and glass, because of these difficulties. And thermosetting plastics, which cannot be heated and remoulded, are hardly ever recycled. Tough chemical or physical treatment involving high temperatures and pressure is normally needed to break them down into reusable substances. But the researchers have shown in laboratory experiments that liquid salts or 'ionic liquids' can dissolve nylon back into its basic chemical units.

Ionic liquids are closely identified with the 'green chemistry' movement because they rarely evaporate, so cannot be inhaled and do not form smog. Like all salts, they are made up of positive and negative ions. But unlike most salts they have unwieldy ions that refuse to stack neatly into crystals like table salt, and instead exist as a disorganised liquid.
New Scientist / Organic Letters    Jun 21, 2007 back to top

Better biofuel uses best of both worlds
Researchers at the University of Wisconsin-Madison in the US have made a new type of biofuel with more energy than ethanol, and which can be produced more quickly and efficiently than other biofuels.

At present biofuel - most commonly in the form of ethanol - is produced biologically, using microorganisms to break down raw biomass into simple sugars, which are then fermented to produce ethanol. Ethanol is a far from perfect fuel - its production can be slow and the amount of energy it produces is vastly less than conventional fuels such as petroleum.

But now the researchers have created dimethylfuran (DMF), using a combination of conventional biological and new chemical methods. Their approach is quicker and uses far less energy than existing chemical procedures. They first use microorganism- derived enzymes to break down raw carbohydrate chains into fructose. Then an acid and a metal are used to catalyse reactions that remove oxygen molecules from the mix - minimal oxygen being more desirable in transportation fuel.

DMF is superior to ethanol in several ways. It boils at 20 degrees Celsius higher than ethanol, meaning it remains as a liquid in the fuel tank and becomes a vapour in the engine - necessary for a fuel. DMF also has a 40% higher energy density than ethanol, requiring a smaller fuel tank, and repels water, so the fuel will not absorb moisture from the air like ethanol.
SciDev / Nature    Jun 21, 2007 back to top

Researchers show off sugar cube sized fuel cell
Scientists at Japan's National Institute of Advanced Industrial Science and Technology (AIST) have developed a miniature fuel cell power source which is as small as a sugar cube. A fuel cell of this size would be suitable for a variety of applications, including mobile electronic devices, portable general-purpose power units and even vehicle power supplies.

The technology has an average power output of at least two watts per cubic centimetre, and the cells operate at a relatively low temperature of 600C or less. AIST claims that this is the highest output power density ever achieved for such a low temperature fuel cell. The micro fuel cells have been tested using a hydrogen and air fuel mix to generate electricity.

In typical applications, the micro fuel cells could be stacked to create a larger unit. A small array of fuel cells might have a volume of several cubic centimetres, with an output of tens of watts. A larger unit with a size of thousands of cubic centimetres would be able to generate several kilowatts of power, the researchers predict.
VNUnet UK    Jun 20, 2007 back to top

'NanoSQUIDs' to improve magnetic microscopes
The tiniest version yet of a superconducting device that measures faint magnetic fields has been created by researchers at the University of Twente in the Netherlands. It could be used to improve the resolution of magnetic microscopes.

SQUIDs (superconducting quantum interference devices) can measure vanishingly small magnetic fields. The most sensitive type is made from a loop of superconducting metal with two junctions. The junctions present an obstacle to superconducting current or 'supercurrent' flowing through the loop and, thanks to quantum properties of superconducting materials, this effect is closely related to the magnetic field of the loop. So, monitoring the current provides a roundabout way of measuring a nearby magnetic field. Scanning SQUID microscopes (SSMs) run a small SQUID over a sample to build up an image of its magnetic properties.

Previously, so-called nanoSQUIDs have been used to 'record' the magnetic flux over an area of around one micron square. But the device created by the Twente team has been used to look at areas more than thirty times smaller, just a few hundredths of a micron. The devices were made from strips of niobium metal, which superconducts when chilled to 9.3 kelvin. This cuts through the metal leaving only two thin 'nanobridges', each 80 nanometres across, holding the strip together and forming a completed loop. The two bridges constitute the junctions that obstruct the supercurrent and the remainder of the strip.
New Scientist / Nanoletters    Jun 19, 2007 back to top
 
         
  © UNU-MERIT | webmaster