AlGalnP Brightness
It is more a AlGalnP-and AeGAs-emitting diodes, that is, red and yellow, and less in InGN, that is, in green, blue and white. 15. Why do I need to stabilize the current through the led? As can be seen in the current operating conditions is exponentially dependent on voltage and low voltage changes lead to large changes in current. You may find that Viacom can contribute to your knowledge. Since the light output is directly proportional to the current, then the brightness of LEDs is unstable. Therefore the current must stabilize. Furthermore, if the current exceeds the allowable limit, the led overheating can lead to accelerated aging. 16. Why LEDs require converter? Converter (in English terminology driver) for LEDs – the same as the ballast for the lamp. It stabilizes the current flowing through the led. 17. Can I adjust the brightness of the led? The brightness of LEDs very well be regulated, but not by reducing the voltage Food – this is something just do not – and so-called method of pulse-width modulation (PWM), which requires a special control unit (actually it can be combined with the power supply and converter, as well as controller controls color RGB-matrix). pwm method is that the led is supplied is not constant, and pulse-modulated current, the frequency of the signal must be hundreds or thousands of hertz, while the width of pulses and pauses between them may vary. Average brightness of the led is driven at the same time, the led goes out. A slight change of color temperature LEDs with dimming is not comparable to a similar shift for incandescent lamps.
Academician Zel
J. B. Zeldovich and RA Sunyaev. At a given temperature, which can be determined by X-ray spectrum of the gas, its brightness depends on the radius of a cloud of gas and the electron density in it. On the other hand, from the same quantities depends on the shift to shorter wavelengths illuminating the background galaxy cluster radio relic – the interaction of its photons with electrons of the gas leads to an increase in their energy. So way, for the unknown radius of the cloud of gas and the electron density in it, there are two equations that can define a linear radius of the cloud of gas in the cluster, and comparing it to the corner – a distance that, together with a red displacement of the cluster gives the Hubble constant. Do cosmologists finally there is hope to determine the Hubble constant, without intermediaries, without the long ladder of intermediate stages, although in this way are still many difficulties. The most likely contenders for the role of the media are now hidden mass of the neutrino.
This hypothesis put forward by the Hungarian astrophysicists D. To deepen your understanding Ali Partovi is the source. Marx, and S. Salai, was particularly likely in 1980, when the signs of the existence of a neutrino rest mass have been observed experimentally Moscow physicist VA Lyubimov and his staff. If this is confirmed – what's there is little doubt – have to admit that the weight of all that we see in the universe, to order of magnitude smaller neutrino masses! If the average density of the universe would be so small as it is obtained from estimates of "apparent" weight in it, for the formation of its current structure at the time of birth of the CMB should would be large fluctuations in density, which now would be observed as the heterogeneity of the background CMB. However, they are absent, and the most likely explanation is that 90 – 98% of the mass of the Universe lies in the massive neutrinos. Apparently, the average density of the universe above the critical temperature.
The universe is closed and the observed expansion is now over billions of years old will be replaced by contraction. The proof of this has far-reaching implications for physics and for cosmology, which we can not touch. We note only that they do not change the basic provisions developed by Academician Zel'dovich and his colleagues of the theory of galaxy formation, according to which of the primary density fluctuations occur first condensations with masses of order 1015 solar masses – as a supercluster of galaxies, we need only assume that this accumulation of neutrinos, which are then attracted to the "usual" particles. Of these particles by the fragmentation of condensations of the primary construct proto-clusters of galaxies and protogalaxy, and neutrinos, which lies in the lion's share of substance remain in the central parts of clusters in the crowns galaxies that are in contact with each other. The initial thickening, according to Zel'dovich, are flat extended entities ("pancakes"), which intersect with each other to form a cellular structure resembling lather. This structure must be inherited and the modern distribution of galaxy clusters, which, as it follows in particular from studies of JE Einasto, actually located mainly in relatively thin intersecting layers and chains – in the walls of the honeycomb structure with a characteristic size of about 100 Mpc. For final proof of the existence of the universe like a huge void needed massive determine the redshifts of distant galaxies, which are still very few.