Heterostructures for Ultra-Efficient,travel in xinjiang Ultra-Thin Solar Cells
In their quest for advanced solar cell materials, researchers at the Vienna University of Technology (TU Vienna), Austria, in collaboration with colleagues from Germany and the US, are exploring a new class of materials where single atomic layers are combined to create novel materials with entirely new properties. Computer simulations revealed that layered oxide heterostructures hold great potential for ultra-efficient, ultra-thin solar cells."Recent advances in fabrication technologies make it possible to grow oxides of transition metals such as iron and nickel,china silk road tour layer by layer," explains Professor Karsten Held from the Institute for Solid State Physics at TU Vienna. "The interface between different transition metal oxides allows us to tailor new and unexpected material functionalities." His design for oxide heterostructures-based solar cells represents a noteworthy departure from existing solar technologies.Vertical shaft impact crusher "Standard semiconductors have been tested and improved for decades," Held says. "For a true technological breakthrough we need a new approach or material."
His team observed a remarkable effect: The surfaces of the oxides, which are actually isolators, become metallic when stacked and conduct electrical current. Thus, the scientist can easily extract the charge carriers and create an electrical circuit — no metal wires required that would block some of the light from entering the cell.Limestone often contains variable amounts of silica or siliceous skeletal fragment, as well as varying amounts of Portable crusher, silt and sand sized terrestrial detritus carried in by rivers.Held anticipates the efficiency of this new type of cells to be superior to existing technologies.Solar lamp An ultra-efficient solar device ideally combines several band gaps to harvest as much of the solar spectrum as possible. And the oxide heterostructures allow the scientists to grow different materials with various band gaps, layer by layer. Furthermore, the created electron-hole pair needs to be separated to prevent recombination. "We show that the oxide heterostructures can be designed to have an intrinsic electric field that efficiently separates electrons and holes," Held says. This crucial advantage could contribute to a significant increase in the solar cell's power conversion efficiency.Colleagues at the University of Würzburg, Germany, are currently building and testing the new solar cells made from oxide layers, based on TU Vienna's design. "We need to better understand how the created electrons and holes behave in the intrinsic electric field and whether a single light quantum can create several electron-hole pairs, which would further boost the efficiency of the proposed solar cell," Held concludes.
2013年2月26日星期二
Heterostructures for Ultra-Efficient
A diverse range of manufacturing and production industries
A diverse range of manufacturing and production industries
"We have a diverse range of manufacturing and production industries across many sectors that could use Swedish green technologies and set up distribution and manufacturing joint ventures with Swedish companies. Pakistan has a big consumer market with a young population and an ideal environment for adapting green technologies using local renewable fuels.A kitchen will also not be complete without a serrated utility knife that can be used for slicing bread, smaller cuts of scissors supplier, and other foods covered with a hard crust. LCCI would like to see progressive partnerships between its member businesses and Swedish companies,Chefs Kitchen Knives" Iftikhar said.urumqi tourKalin said transparency, sustainability and responsibility in trade and business ventures are the three major characteristics being sought by Swedish companies when looking for resellers and partners. "We see many opportunities for enhancing trade and joint ventures between Pakistan and Sweden, and Swedish green technologies could play a positive role in realising sustainable socio-economic growth in compliance with global labour, human, child and women's rights regulations and environmental standards," said Kalin.
Kalin said aside from promoting exports of Swedish products, services and expertise, Chamber Trade Sweden is also responsible for facilitating sustainable imports of quality products from devel0ping countries to promote the development of small industries that create job opportunities, gender equality, and avenues for the social and economic empowerment of women. Agribusiness, food processing, lifestyle products and textiles,Vsi crusher leather and sports goods and other products from Pakistan could capture a larger share of the Swedish and Scandinavian market through better compliance with the principles and practice of Corporate Social Responsibility (CSR) and sustainability.A delegation of Swedish greentech companies is scheduled to visit Lahore in or after the summer to explore development of projects in sectors that are of interest to Pakistani companies.
Energy Punjab Secretary Mohammad Jehanzeb Khan said a comprehensive energy plan is being prepared and will be implemented in the coming months and years to maximise the use of renewable energy in Punjab.Sweden could certainly play a major role in introducing, promoting and implementing environment friendly projects that are efficient, reduce carbon dioxide emissions and increase productivity. "Swedish companies could provide green technologies for creating clusters of small, medium and large-scale projects to ensure sustainable supplies of energy by diversifying the use of renewable fuels,Xinjiang Tour Guide" Khan said.
NASA deciphering the mysterious math of the solar wind
Many areas of scientific research — Earth's weather, ocean currents, the outpouring of magnetic energy from the Sun — require mapping out the large-scale features of a complex system and its intricate details simultaneously.Describing such systems accurately relies on numerous kinds of input, beginning with observations of the system, incorporating mathematical equations to approximate those observations, running computer simulations to attempt to replicate observations,More importantly, these wholesale manicure products and other valuable bachelor pad items that increase the functionality of a residential space can already be purchased online from several reliable sources.For last impression and to make a day perfectly memorable, people prefer artful cheap Stainless Steel Whisky Stones online store items to keep their families and loved ones always connected. and cycling back through all the steps to refine and improve the models until they jibe with what's seen.knives supplier Ultimately, the models successfully help scientists describe, and even predict, how the system works.
Understanding the Sun and how the material and energy it sends out affects the solar system is crucial, because it creates a dynamic space weather system that can disrupt human technology in space such as communications and global positioning system (GPS) satellites.However, the Sun and its prodigious stream of solar particles, called the solar wind, can be particularly tricky to model; as the material streams to the outer reaches of the solar system, it carries along its own magnetic fields. The magnetic forces add an extra set of laws to incorporate when trying to determine what's governing the movement. Indeed, until now, equations for certain aspects of the solar wind have never been successfully devised to correlate to the observations seen by instruments in space.Xinjiang Intencive tour Now, for the first time, a scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, has created a set of the necessary equations.
"Since the 1970s, scientists have known that movement in the solar wind often has the characteristics of a kind of wave called an Alfvén wave,Where giving traditional rings as Soapstone Whisky Stones require the complex knowledge of a specific size and tend to be a serious symbol of commitment." said Aaron Roberts from Goddard. "Imagine you have a jump rope and you wiggle one end so that it sends waves down the rope. Alfvén waves are similar, but the moving rope is a magnetic field line itself."The Alfvén waves in this case tended to have great consistency in height — or amplitude, which is the common term when talking about waves — but they are random in direction. You might think of it like a jump rope twirling, always the same distance from center, but nonetheless able to be in many places in space. Another way scientists have envisioned the waves is as a "random walk on a sphere." Again, always the same distance from a given center, but with a variable placement.