Light at night

27 12 2011

Astronaut photograph ISS030-E-10008 was acquired on December 4, 2011, with a Nikon D3S digital camera using a 24 mm lens, and is provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Center. The image was taken by the Expedition 30 crew. The image has been cropped and enhanced to improve contrast. Lens artifacts have been removed. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public.


Dialèctica i tragèdia

20 12 2011

Podem discernir quelcom de la gramàtica “tràgica” sota la manera proverbial del grec de dir “u apren de l’experiència”: “ta pathemata mathemata,” “el que pateix aprén.” També podem entreveure una relació entre la dialèctica i les matemàtiques (un tipus que haguera pogut figurar en la insistència de Plató en les matemàtiques) en el fet que mathemata vol dir tant les coses apreses en general, com les ciències matemàtiques (aritmètica, geometria, astronomia) en particular. Un pathema (de la mateixa arrel que la nostra paraula “passiu”) és l’oposat d’un poiema (un fet, acció, acte; qualsevol cosa feta; un poema). Un pathema es pot referir variadament a patiment, infortuni, condició passiva, situació, estat mental. El requeriment inicial d’una tragedia, però, és una acció. Així doncs, segons la nostra interpretació, si el proverbi s’haguera de completar, a risc de redundància, tindria tres termes: poiemata, pathemata, mathemata, suggerint que el fet organitza la oposició (trau al front els factors que siguen que resisteixen o modifiquen l’acte), que l’agent que “pateix” esta oposició, en tant que aprén a prendre els motius oposicionals en consideració, ampliant en conseqüència la seua terminologia, ha arribat a un ordre superior de comprensió. Ara bé, esta descripció indica una seqüència temporal que no és normalment el cas. Les tres distincions es poden col·lapsar en un únic “moment,” de manera que podem procedir d’un a l’altre en qualsevol ordre.

Kenneth Burke “A Grammar of Motives” (1945) p. 39. Traducció meua.

Virtual Physics

19 12 2011

Here is a collection of experiments in mechanics, thermodynamics and electromagnetism for graduate student physics lab. I dessigned some of the original experiments many years ago. Now Noemi Sanchis has directed the virtual version, and they look nice and helpful.

Virtual Physics Experiments

Karl Leo and team awarded prize for Innovation and Technology by the German Federal President Christian Wulff

17 12 2011

Congratulations Karl

Press release. Dresden, Germany, 15. December 2011

German Federal President awards Novaled’s founders team for the Deutscher Zukunftspreis 2011

Novaled AG, a leading company in OLED and organic electronics technology and materials, is pleased to announce that three of Novaled’s founders have been rewarded with the prize “Deutscher Zukunftspreis 2011” for Innovation and Technology by the Federal President Christian Wulff.

The  team of Prof. Karl Leo (Technical University of Dresden and Fraunhofer IPMS  Dresden), Dr. Jan Blochwitz-Nimoth (Novaled AG) and Dr. Martin Pfeiffer (now  Heliatek GmbH) received in Berlin the Deutscher Zukunftspreis – the German  federal president’s prize for Innovations in Science and Technology. This  annual prize honours creative teams of people realizing breakthrough achievements  in science and the subsequent industrial exploitation of these new scientific  results. “I am very glad that this team won the award”, said German Federal  President Wulff. “…the topic of this team is particularly promising  because it really can make happen the energy turnaround (towards green  energy).”

„We are very happy about this precious award which is an honor and great recognition of the work of the Novaled team and our partners”, says Dr. Blochwitz-Nimoth, Chief Scientific Officer of Novaled. “At the same time the award is motivating us, to make our vision become reality to significantly improve our life in the 21st century with the help of organic electronics.”

The winners team made remarkable developments in the field of Organic Electronics. At the Technical University Dresden they developed unique OLED technologies able to radically reduce the energy consumption of an OLED product. These technologies find their application in new generations of flat panel display, low power lighting and efficient and flexible solar cells.

Karl, Jan, and Martin are at the origin of a strong Organic Electronics cluster in Saxony; especially with the creation of Novaled AG and Heliatek GmbH (a producer of organic solar cell products).

The spin-off Novaled has meanwhile successfully commercialised its OLED technologies and materials. Both are used for mass production and can be found in products like new generation flat panel displays (e.g. mobile phone displays) and in energy efficient OLED lightings and Organic Solar Cells.

About Novaled
Novaled AG is a world leader in the OLED (Organic Light Emitting Diode) field and specializes in high efficiency long lifetime OLED structures and is an expert in organic electronics. The company is known for its Novaled PIN OLED® technology, its proprietary OLED materials and the customized OLED products and services. Novaled has developed long term partnerships with major OLED producers throughout the world. Based on more than 500 patents granted or pending, Novaled has a strong IP position in the field of OLED technology. Since 2003 the spin off of Technical University (IAPP) and Fraunhofer (IPMS) Dresden is active in the market. Novaled has some 120 staff worldwide with headquarters in Dresden and offices in Korea and Japan. The company was named No. 1 in a list of ‘up and coming’ world market leaders by the German newspapers Handelsblatt and Wirtschaftswoche. Its main investors include eCAPITAL, Crédit Agricole Private Equity, TechnoStart, TechFund and CDC Innovation. For further details please visit
Contact: Ms Anke Lemke, phone: +49 (0)351 796 5819 or

About OLEDs
OLEDs (organic light-emitting diode) are semiconductors made of thin organic material layers of only a few nanometers thickness. They emit light in a diffuse way to form an area light source. In a fast growing display market OLEDs are key part of a revolution: the dream of paper-thin, highly efficient displays with brilliant colors and great flexibility in design. OLEDs represent the future of a vast array of completely new lighting applications. By combining color with shape, organic LEDs will create a new way of decorating and personalizing personal surroundings with light.

L’Odissea en valencià

16 12 2011

Ai, els mortals ens culpen, als déus, de tantíssimes coses!
Diuen que som el motiu dels seus mals, mentre són ells mateixos,
per insensats i per boigs, els qui es busquen dolors sense mida.

S’acaba de publicar l’Odissea, d’Homer, traduida al català pel millor escriptor valencià (viu), Joan F Mira.

És una versió erudita però natural, és llig fàcil i sense perdre el ritme profund, pots disfrutar perfectament el llenguatge a més de les eternes aventures de la èpica més lírica. Això no passava en les traduccions anteriors.

És el moment de llegir l’Odissea una altra volta en català amb gust valencià.


EU policies on Solid State Lighting

15 12 2011
Excerpt of te European Commission  Green Paper

SSL technologies for general lighting applications comprise LED and OLED light sources, luminaires and control gear. They produce white light in different colour tones and variations, from warm to cold white. LED lamps and luminaires integrate high-brightness LED point light sources. OLED devices are based on organic light sources (e.g. polymers) that emit light homogeneously from a two-dimensional surface and can be made in arbitrary shapes and sizes, including as transparent panels.
Lighting is an essential service for domestic use, in public spaces and other applications, from advertising panels, automotive, traffic and street lights to public offices and buildings. In Europe, professional lighting (non-residential buildings and street lighting) accounts for 52% of the total market revenues and residential lighting for the rest. Office buildings use up to 50% of their total electricity consumption for lighting, while this share is 20-30% in hospitals, 15% in factories, 10-15% in schools and 10-12% in residential buildings.
While LEDs have become available on the general lighting market as spotlights integrated in ceilings and as “retrofit” light bulb replacements, recent LED technology advancement has allowed their integration and use in far more demanding applications: street lighting, high-brightness indoor and outdoor lighting, retail displays, general merchandise lighting, etc. Shopping malls quickly followed the trend and some achieved energy savings of 60% and payback times of about 3 years. LED lighting is also appreciated in hotels where refurbishments achieve up to 90% higher efficiencies compared to previous installations. The potential for LED deployment in Europe is very large, as 75% of existing lighting installations are older than 25 years.

Get the full document

Growth of BIPV

9 12 2011

By Renewable Energy World Network Editors

Building-integrated photovoltaics (BIPV) currently make up a small but increasing part of the world PV market, and many analysts predict a growth explosion in the sector, resulting in a multibillion-dollar annual market segment. The global BIPV market was estimated at 1201 MW in 2010 and is expected to increase at a 56% compound annual growth rate (CAGR) to reach a capacity of 11,392 MW in 2015, according to Building-Integrated Photovoltaics (BIPV): Technologies and Global Markets, a new report from analysis firm BCC Research.

BIPV roofing is the largest near- and mid-term market segment, the report says and the global market for BIPV capacity in the roofing sector was 404 MW in 2010 and is expected to reach 3197 MW in 2015, a CAGR of 51 percent. The BIPV sector had a manufacturing capacity of just 200 kW in that year, but BCC Research expects it to increase at a 670 percent CAGR, reaching a capacity of 5439 MW in 2015.

Full article

Characteristics of Organic Bulk Heterojunction Solar Cells

6 12 2011

This is the talk presented 1 december 2011 at MRS Boston

Characteristics of Organic Bulk Heterojunction Solar Cells Investigated by Impedance Spectroscopy.

This is work done with my colleague Germà Garcia-Belmonte and other collaborators. We describe our view of the basic mechanisms of this type of solar cell. Much of these ideas aim to build a simple and useful model for the BHJ solar cell that is consistent with impedance spectroscopy mesurements. This is a very powerful characterization technique but to use it, we first need to establish how to do and interpret the measurements.

Some people asked to have the talk so here I publish for everybody interested.


Follow up:

Direct observation of internal potential distributions in a bulk heterojunction solar cell
Jongjin Lee, Jaemin Kong, Heejoo Kim, Sung-Oong Kang, and Kwanghee Lee
Appl. Phys. Lett. 99, 243301 (2011)