4 Roma e il Mit, le auto seguite con i telefonini: a settembre monitoraggio in tempo reale dei movimenti dei cittadini Il Grande Fratello del traffico così si controlla la mobilità Le tracce dei cellulari diventano punti rossi su un display Prevista l'installazione di maxi-schermi per informare gli automobilisti ROMA - La grande mappa, una specie di enorme Tuttocittà satellitare, comincia ad animarsi all'alba. Prima, sulle strade semideserte, solo qualche puntino isolato si muoveva veloce per poi spegnersi nel silenzio della notte. Sono quasi le sei di mattina quando, scosso dal ronzio delle prime radiosveglie, il quadro si anima. Le vie si popolano di luci. Una processione di lucciole pigre emerge dai garage, si raggruppa alle fermate degli autobus, scende nei tunnel del metrò. Sembrano migliaia di formiche con un casco da minatore che ne illumini il cammino. Ma questi pendolari che lentamente dalla periferia viaggiano verso il centro, non hanno una luce in testa, ma un cellulare in tasca. I telefonini, nei quali qualcuno di loro già parla, parlano di tutti loro: quanti sono? Dove vanno? La città che si sveglia registra questi dati, ci si guarda come in uno specchio e ad essi si adatta: dove servono più autobus? Qual è la strada più sgombra per andare da qui a lì? Città simili a organismi viventi, che si modellano in tempo reale sulle esigenze degli abitanti. Per chi invecchia nelle code delle tangenziali, è solo un sogno. Per gli assessorati alla mobilità, quasi fantascienza. Per i ricercatori del Massachusetts Institute of Technology, è un progetto da realizzare oggi, con tecnologie note e disponibili. A Roma l'onore di essere, a settembre, la prima capitale che sperimenterà il servizio. "Si tratterà di un test unico nel suo genere, sia per la grandezza del campione che per il livello delle tecnologie coinvolte", spiega Carlo Ratti, direttore del Senseable City Lab presso il Mit. Nelle grandi città, milioni di cellulari comunicano in ogni momento la loro esatta posizione agli operatori gsm. Niente di sorprendente: i telefonini funzionano proprio perché aziende
5 come Tim, Vodafone, Wind e H3G possono localizzarli in ogni momento e seguirli con il loro segnale. A Roma il Mit prenderà i dati sulla posizione dei cellulari forniti da Telecom Italia sotto forma di aggregati anonimi, li farà digerire ai suoi computer di Boston, e li rispedirà indietro trasformati in mappa dei movimenti dei romani. Questo procedimento, che coinvolge algoritmi particolarmente complessi (in grado di capire, ad esempio, se un telefonino molto lento si trova nelle tasche di un pedone o di un automobilista incolonnato nel traffico) avverrà in maniera quasi istantanea, così da fornire aggiornamenti in tempo reale sulla situazione della città. Con uno strumento del genere a disposizione, si può scegliere non solo la strada più scorrevole per andare al ristorante, ma anche il locale meno affollato. Seguendo i telefonini in base al loro prefisso, si possono individuare i flussi turistici: dove vanno i tedeschi? Come si spostano i giapponesi? Combinando i dati sul traffico con quelli sul flusso dei mezzi pubblici, si può capire immediatamente se la distribuzione dei bus corrisponde alla densità e alle esigenze dell'utenza. Sullo schermo del proprio cellulare, ognuno potrebbe individuare in qualunque momento il taxi più vicino, e chiamarlo. Oppure sapere sempre dove si trova il primo parcheggio disponibile. Il progetto "Real-time-Rome" sarà presentato a settembre in occasione della 10 Mostra internazionale di architettura alla Biennale di Venezia. L'anno scorso, Ratti e il suo team avevano condotto un primo test su piccola scala a Graz, in Austria. Oggi, la scelta di Roma non è casuale: "Nel 1748, la pianta dell'urbe di Nolli diede il via alla cartografia moderna", spiega Ratti. "Le mappe del futuro saranno enormi database dai quali estrapolare frammenti a seconda delle proprie esigenze, come si fa su internet". A Roma, inoltre, Telecom sta installando una rete particolarmente avanzata, ideale per fornire al Mit le informazioni di cui ha bisogno. Al progetto partecipano anche Google, Atac, Samarcanda Taxi e il Campidoglio, che durante la sperimentazione prevede di montare megaschermi sui quali i romani potranno seguire i propri movimenti nella città. Si valuteranno così i benefici del progetto, e anche i suoi effetti collaterali: "Nel campus del Mit, dove un sistema simile funziona da tempo, organizzare una riunione che inizi in orario è diventato impossibile", racconta Ratti. "Nessuno si presenta finché non vede che sono arrivati gli altri partecipanti. Va a finire che i questi meeting non iniziano mai".
6 Un sottile film di proteine potrebbe dare ai DVD la memoria di un hard disk DVD ricoperti da uno strato di proteine potrebbero contenere un giorno tanta informazione quanto quella contenuta nell'hard disk di un personal computer. Venkatesan Renugopalakrishnan, un professore della Harvard Medical School di Boston, ha spiegato alla International Conference on Nanoscience and Nanotechnology di Brisbane che questi strati sarebbero composti da proteine ricavate da microbi geneticamente modificati. Il risultato sarebbe un DVD in grado di contenere terabytes di informazione. "Congegni di questo tipo potrebbero eliminare del tutto la necessità di memorie come l'hard disk", ha spiegato il ricercatore, che ha aggiunto anche come questi DVD potrebbero venire incontro alle necessità dell'industria militare o farmaceutica che oggi devono trasferire grandi quantità di dati via satellite o sotto forma di filmati a causa della inadeguatezza delle tecnologie di immagazzinamento magnetico. Il concetto di base è quello di immagazzinare in proteine grandi pochi nanometri l'informazione. Si tratta di proteine attivate dalla luce, che si trovano nelle membrane di un batterio chiamato Halobacterium salinarum che vive nelle paludi salmastre. Battezzata bacteriorhodpsin la proteina cattura la luce e la trasforma in energia chimica attraverso una serie di passaggi, nel corso dei quali la proteina diventa una serie di molecole intermedie ognuna caratterizzata da una forma e un colore unici.queste molecole hanno una vita breve, solo qualche giorno o qualche ora. Grazie però ad alcune modifiche genetiche, il ricercatore è riuscito a produrre delle varianti con una vita media di qualche anno. In media, un DVD alle proteine potrebbe raggiungere i 50 terabyte di informazione. Grazie ai finanziamenti della casa giapponese Nec, Renugopalakrishnan ha prodotto alcuni prototipi e pensa di poter commercializzare la prima versione di una pendrive tra un anno circa e il primo DVD tra due anni.
7 Microelectronics & Nanotech
8 EU project gives insight into future of nanotechnology An EU funded project has published a series of roadmaps, providing an overview the current situation and future of nanotechnology in three fundamental sectors: materials, health and medical systems, and energy. The past years have seen an unprecedented growth in research and development (R&D) activity in the field of nanotechnology, propelled by the belief that nanotechnology represents a radically new approach to manufacturing. Experts believe that the technology will revolutionise practically all industrial sectors as well as everyday life, and that this revolution is not so far in the future. Knowing how nanotechnology will develop in the coming years, as well as which applications will be more relevant, will be of considerable value to those planning for the future. NanoRoadMap is funded under the 'nanotechnologies and nano-sciences, knowledge-based multifunctional materials and new production processes and devices' thematic priority of the Sixth Framework Programme (FP6). The NanoRoadMap consortium gathers eight research and industrial partners from the public and private sectors from the Czech Republic, Finland, France, Germany, Italy, the Netherlands, Spain, the UK and Israel. A total of 12 roadmaps are grouped into three sectoral reports, which give details of the properties of each technology, as well as the challenges and barriers to their current and future applications. The report predicts that nanomaterials will be developed the most over the next 10 years. Nanomaterials are novel materials whose elemental structure size has been engineered at the nanometre scale. At this dimension, materials exhibit greatly improved or totally new behaviours and properties. Because of their ubiquitous nature, nanomaterials can find application in a variety of markets, ranging from catalysis to membranes for fuel cells. Carbon nanotubes are the best-known nanomaterial. However, the wide spectrum of possible applications envisaged, the report says, makes it difficult to estimate with a reasonable accuracy the dimension of future markets. One market that will see an impact is the medical sector. The report notes that research into the rational delivery and targeting of therapeutic and diagnostic agents is already quite advanced, and nanotechnology will be increasingly used to create systems which can allow drugs to target specific areas within the body. With the help of nanotechnology, the medicine is moving towards more individualised treatments. Using particles smaller than 50 nanometres, or even 20 nanometres, drugs or drugs carriers can move through the walls of blood vessels, easily interacting with molecules on both the cell surface and within the cell, often in ways that do not alter the behaviour of those molecules. However, despite the huge expectations surrounding the use of nanoparticles for medical purposes, the technology is still at an early stage of development, and the report cautions that several problems need to be solved or circumvented to attain results. For example, the interaction between nanoparticles and 'intracorporeal targets' need still to be explored to in order to increase understanding of the complex biological basic principles governing the impact of these specific applications. According to the report's experts, one of the most important challenges is linked to the possible side effects or potential cell toxicity of available nanoparticles. It is important that any side effects do not prevail over the therapeutic effects of the drug. Public support at the early stages of the research is a priority, says the report, and an attempt to somehow simplify the approval processes (without, of course, any loss of quality and security within the process itself) should be considered.
9 Nanotechnology is also considered potentially promising all along the energy pipeline, from production to transmission, to distribution, conversion and utilisation, offering alternative ways of energy generation, storage and saving. According to the report, while the technology is only at an early stage of development, European research into nanoscience is already prevalent in the key alternative energy sources solar energy, thermoelectricity, rechargeable batteries, and supercapacitors. European industry is also seen to be competitive in a number of areas. In nanotechnology-related heat insulation and conductance, for example, the position of European industry is thought to be good or excellent by most of the report's experts. In solar cells, there are a number of large European companies and some start-ups that the experts consider to be in quite a good position. Also in rechargeable batteries and supercapacitors the position of European small and medium sized enterprises (SMEs) is rated from satisfactory to good. However, the report suggests that these are notable exceptions, finding that European industry is lagging behind its counterparts in the US and South East Asia. In the case of thermoelectricity, the vast majority of companies cited by report's experts as contributing the most to advancing nanotechnology in this field are based in the US. The competitive position of European industry also varies depending on the sectors and size of a company - large enterprises or SMEs. The energy roadmap reflects an overall difficulty in all three sectors under review - transferring knowledge on nanoscience from academia to industry. Given that many of the barriers encountered in one sector are present in others, the report suggests the creation of multidisciplinary centres to advance knowledge transfer on materials development/application and their own pilot production facilities. These centres will favour cooperation, facilitate access to sophisticated equipment, help to transfer research results into products, scale up production processes in line with industry requirements, and train people. Both academia and industry, most of all SMEs, would benefit from such centres, says the report. The report's recommendations are summarised below: - fundamental research for understanding structure-property-processing relationship at the molecular level; - computer modelling and simulation at the nanoscale; - online tools for characterisation, process monitoring and control; metrology; - developing a standard regulatory framework and common approval procedures; - identifying and pre-developing materials, applications and capabilities that respond to the stringent needs of mass production, thus reducing the risk associated with their development; - scaling up production; - improving collaboration between academia and industry and technology transfer; - providing education and skills both for young researchers and co-workers; - answering increasing concerns on health, safety and environment issues; - fostering transparent discussion and information with all the stakeholders on the benefit and risks of nanotechnology. To read the reports in full:
10 Paint-on Semiconductor Outperforms Chips Researchers at the University of Toronto have created a semiconductor device that outperforms today s conventional chips and they made it simply by painting a liquid onto a piece of glass. The finding, which represents the first time a so-called wet semiconductor device has bested traditional, more costly grown-crystal semiconductor devices, is reported in the July issue of the journal Nature. Traditional ways of making computer chips, fibre-optic lasers, digital camera image sensors the building blocks of the information age are costly in time, money, and energy, says Professor Ted Sargent leader of the research group. Conventional semiconductors have produced spectacular results but they rely on growing atomically-perfect crystals at 1,000 degrees Celsius and above, he explains. The Toronto team instead cooked up semiconductor particles in a flask containing extrapure oleic acid, the main ingredient in olive oil. The particles are just a few nanometres (one billionth of a metre) across. The team then placed a drop of solution on a glass slide patterned with gold electrodes and forced the drop to spread out into a smooth, continuous semiconductor film using a process called spin-coating. They then gave their film a two-hour bath in methanol. Once the solvent evaporated, it left an 800 nanometre-thick layer of the light-sensitive nanoparticles. At room temperature, the paint-on photodetectors were about ten times more sensitive to infrared rays than the sensors that are currently used in military night-vision and biomedical imaging. These are exquisitely sensitive detectors of light, says Sargent, It s now clear that solutionprocessed electronics can combine outstanding performance with low cost. The key to our success was controlled engineering at the nanometre lengthscale: tailoring colloidal nanocrystal size and surfaces to achieve exceptional device performance, says coauthor Gerasimos Konstantatos. With this finding, we now know that simple, convenient, low-cost wet chemistry can produce devices with performance that is superior compared to that of conventional grown-crystal devices.
11 Nano Lubrication Could Make Possible Ultra-Dense Memory A new way to reduce friction at the nanoscale could enable the commercialization of nano mechanical devices, including ones for data storage. Researchers have helped to smooth the way for memory chips that are 10 to 100 times denser than today's devices, by developing a way to cut down on friction at the nanoscale. The method could have far-reaching implications for both micro- and nano-electromechanical systems (MEMS and NEMS), which are used for storage and other applications in communications and computing. Liquid lubricants do not work at the nano scale; as a result, tiny mechanical devices can wear out too fast to be practical. Now physicists at the University of Basel in Switzerland have developed a dry "lubrication" method that uses tiny vibrations to keep parts from wearing out. The method, described in the current issue of Science, could be particularly useful for a new class of memory devices-such as new IBM s Millipede- which uses thousands of atomic force microscope tips to physically "write" bits to a surface by making divots in a polymer substrate and later reading them. The "nano lube" could also find uses with tiny rotating mirrors that might serve as optical routers in communications and mechanical switches, replacing transistors in computer processors, so cutting power consumption. Devices based on NEMS and MEMS are some of the most promising new nanotechnologies. Yet the commercialization of applications such as Millipede has been held up in part by wear caused by friction. Indeed, friction is a particular problem in micro- or nanodevices, where contacts between surfaces are tiny points that can do a lot of damage. "Coming down to nanoscale devices, this contact area gets smaller and smaller, so you have less surface where you can dissipate heat," says Anisoara Socoliuc, co-author of the article. "This leads to wear. It's very easy to break or damage the material at this small scale." In their experiments, the Swiss researchers moved an atomic force microscope tip made of silicon across a test material of sodium chloride or potassium bromide. Ordinarily, the ultra-sharp tip would travel in a "stick-and-slip" fashion, as friction repeatedly builds up until the tip suddenly breaks free. The researchers solved the sticky-tip problem by oscillating the tips using changing voltages. The vibrations, which are so small that the tip stays in continuous contact with the material, keep energy from building up and being suddenly released. As a result, friction decreases 100-fold. This figure shows the dramatic reduction in friction that occurs when an atomic force microscope tip is vibrated as it moves across a surface. Reducing friction could help create very dense memory devices.
12 Nanotubes unwrapped: Carbon sheet solutions Northwestern University researchers have developed a process that promises to lead to the creation of a new class of composite materials -- "graphene-based materials." The method uses graphite to produce individual graphene-based sheets with exceptional physical, chemical and barrier properties that could be mixed into materials such as polymers, glasses and ceramics. The Northwestern team, led by Rod Ruoff, reports the results of their research in the July 20 issue of the journal Nature. "This research provides a basis for developing a new class of composite materials for many applications, through tuning of their electrical and thermal conductivity, their mechanical stiffness, toughness and strength, and their permeability to flow various gases through them," "We believe that manipulating the chemical and physical properties of individual graphene-based sheets and effectively mixing them into other materials will lead to discoveries of new materials in the future." The Northwestern team's approach to its challenge was based on chemically treating and thereby "exfoliating" graphite to individual layers. Graphite is a layered material of carbon with strong chemical bonds in the layers but with moderately weak bonds between the layers. The properties of the individual layers have been expected to be exceptional because the "in-plane" properties of graphite itself are exceptional, but until now it was not possible to extract such individual layers and to embed them as a filler material in materials such as polymers, and particularly not by a scalable route that could afford large quantities. The material containing graphene sheets offers access to a broad range of useful thermal, electrical and mechanical properties for all those applications where carbon nanotubes are too expensive
13 Scientists Image 'Magnetic Semiconductors' On The Nanoscale In a first-of-its-kind achievement, scientists at the University of Iowa, the University of Illinois at Urbana-Champaign and Princeton University have directly imaged the magnetic interactions between two magnetic atoms less than one nanometer apart (one billionth of a meter) and embedded in a semiconductor chip. The findings, published in the July 27 issue of the journal Nature, bring scientists one step closer toward realizing the goal of building a very advanced semiconductor computer chip based "spintronics,". According to Michael Flatté, leader of the UI research group "With spintronics, data manipulation and long-term storage can be conducted in one computer chip, rather than separately in a CPU and a hard drive as currently practiced. The data manipulation could also be done quicker and require less power. Such a computer would be much smaller in size and use less energy," "Visualizing the magnetic interactions on the nanoscale may lead to better magnetic semiconductor materials and applications for them in the electronics industry," says Flatté, lead author of the work, predicted that the magnetic interactions could be imaged with a scanning tunneling microscope. Flatté showed that magnetic interactions depend strongly on where in the crystal lattice of the semiconductor the atoms were sitting. Some configurations interacted very strongly and others very weakly. Flatté team placed the manganese atoms one at a time into a fresh, clean piece of gallium arsenide. "Using the tip of a scanning tunneling microscope, we can take out a single atom from the base material and replace it with a single metal that gives the semiconductor its magnetic properties,". In essence, the team used this unique capability to make a semiconductor magnetic, one atom at a time. A scanning tunneling microscope has a finely-pointed electrical probe that passes over a surface in order to detect variations with a weak electric field. The team found that the charged tip could also be used to eject a single gallium atom from the surface, replacing it with one of manganese that was waiting nearby. By incorporating manganese atoms into the gallium arsenide semiconductor, the team has created an atomic-scale laboratory that can reveal what researchers have sought for decades: the precise interactions among atoms and electrons in chip materials. The team used their new technique to find the optimal arrangements for manganese atoms that enhance the magnetic properties of gallium manganese arsenide. These arrangements agreed with Flatté and Tang's predictions. "To predict how a material will behave, and then have that prediction dramatically confirmed, as in this experiment, is one of the most enjoyable experiences of research," says Flatté. Flatté cautions that further advances will be required to translate the new research results into new chip technology and also that using a scanning tunneling microscope to grow large pieces of high quality gallium manganese arsenide may not be practical. However, he says, the lessons learned about optimal arrangements of magnetic atoms in semiconductors will be transferred to other semiconductor growth techniques and to other magnetic semiconductor materials.