Solar cells for windows

A team at UCLA have developed a transparent solar cell that is an advance toward giving windows in homes and other buildings the ability to generate electricity while still allowing people to see outside. Based on the PEDOT:PSS polymer with a silver metal oxide composite electrode, the devices can exhibit a 66% transparency whilst simultaneously giving a 4% power conversion efficiency. The polymer solar cells are lightweight, flexible and can be produced in high volumes and at low costs.

Open access

The UK government has said that it plans to make publicly funded scientific research available for anyone to read for free by 2014. It is adopting the main recommendations of the French Group that looked into how to expand access to research publications. Research papers that describe work paid for by the UK taxpayer will be free online for universities, companies and individuals to use for any purpose. The funding model will change from one of universities paying subscription fees to journal publishers, to one of authors paying an article processing charge to have their papers peer reviewed, edited and made openly available online. The change will have to be funded from within existing science budgets.

Real time X-rays - to probe Li-S battery degradation

Continuing the theme of Li-ion batteries, a team at Standford University have been investigating lithium - sulphur batteries as a alternative. Most electric cars use rechargeable lithium-ion batteries. These account for more than half of the vehicle's total cost. An alternative is the lithium-sulphur battery, which can potentially store five times more energy at a much lower cost. A major drawback with this technology is that after a few dozen cycles of charging and discharging, the battery stops working. Using X-ray diffraction and transmission X-ray microscopy in real time the group are unravelling the complex formation of polysulphides that form at the electrodes and leaking into the electrolyte limit the battery cycle life.

Towards 450-mm - just another 50% in diameter ...

Within the silicon IC industry momentum is building for the transition to 450-mm wafers from 300-mm wafers, although current thinking is that only the leading-edge chip companies will initially make the move with the first fabs generating products in 2017. The concern has always been the huge cumulative costs of the R&D required to develop a full suite of 450-mm IC production equipment and tools. Estimates of $15bn - £20bn have been made. Last month progress was made with the announcement that Intel and ASML have entered into agreements intended to accelerate the development of 450-mm wafer technology and extreme ultra-violet lithography. The investments including R&D and product developments will total approximately $4.1 billion. The objective is to shorten the schedule for deploying the lithography equipment supporting 450-mm technologies by as much as two years.

This month also saw KLA Tencor announce that their Surfscan wafer defect inspection tool is capable of handling and inspecting 450-mm wafers.

Lightweight research - 75x lighter than Styrofoam

They have named it Aerographite and it is jet black. Scientists at Kiel University and Hamburg University of Technology have created the lightest material in the world, it weighs 0.2 milligrams per cubic centimetre. As such it is 75 times lighter than Styrofoam. The material is a network of porous carbon tubes that is three-dimensionally interwoven at the nano and micro levels formed by CVD of graphite on a zinc oxide sacrificial substrate. One potential application of Aerographite being the electrodes of Li-ion batteries. The full publication is available at this link.

Security gaits

Work is underway to develop special shoe insoles for defining access to high security areas. The shoe insole idea comes from research that shows each of us actually have unique feet and unique ways of walking. Sensors in shoe insoles can check the pressure of feet, monitor gait, and use a microcomputer to compare the patterns to a master file for that individual. If the patterns match then access to an area is allowed, if they don't a wireless alarm message can be issued and access restricted. Three steps are apparently sufficient to delineate between most people. Having read that 123456 and password were the most common passwords of the recently hacked Yahoo accounts perhaps there is an opportunity for Mr Gates to introduce a security gate based on gaits?

Self healing graphene - wonder material properties never cease!

There appear to be no end to the surprises that graphene can heap onto the scientific world. Work at the UK STFC Daresbury Laboratory using the SuperSTEM has shown that graphene undertakes a self-repair mechanism to mend holes. The group had previously observed that metals can initiate the formation of holes in graphene sheets. However recently they have seen that some of the holes were mending themselves spontaneously using nearby carbon atoms to re-knit the graphene structure. Having the capability of structures to reform or self-knit following, for example, a fabrication process would be a beneficial feature for nano device engineers.

RTA August Newsletter

Last month I read a short newspaper article quoting an insurance company. The piece stated that in the UK dancing teachers and choreographers were the most dangerous drivers on the road covering on average 23500 miles between motoring convictions with dental technicians amongst the safest. The piece prompted several negative comments concerning the interpretation of the data, the definitions of safe and dangerous driving and the use of statistics in general. Thinking about these discussions led me to a blog by the economist Jeff Ely in which he notes "......that statistics is a rhetorical practice. The goal is not just to convey information but rather to change minds. " In an ideal world we would all be capable of taking any amount of raw data, analysing it in our own favourite way and arriving at the same conclusions, job done. But the real world contains people like us with prior perceptions, variable knowledge and limited attention spans. We desire certainty, simplicity and clarity of message or we are distracted and move on. Nuances and caveats undermine the power of conclusion. The inevitable tendency is to push data into the background and interpretation into the foreground.

This leads to the dilemma that in order to maximise the impact of the truth one has to filter it. This line between filtering and distorting is a dangerous one to cross.

Science is founded on the unchanging Laws of Nature. Technology help can address the ever changing socio-economic global challenges that confront us but we rarely face decisions to be made with the clarity of certainty in the evidence. Probabilities are just that, probabilities. Statistics may be the heuristics of extrapolating data but it is a much needed discipline.

So who should control the statisticians? It might be relevant to the entire human race and not just dance teachers and choreographers.