Study of cosmic ray intensity measured by mariner ii and by ground neutron monitors during the forbush decrease of september 30, 1962

Cosmic ray intensity measured by Mariner III AND by ground neutron monitors during Forbush decreas

The solar wind velocity and its correlation with geomagnetic, solar and cosmic ray activity

Correlation of plasma velocity with indices of solar and terrestrial activity - cosmic radiatio

Journeys in language learning as adults : a Kannadiga learning Tamil and a Tamilian learning Kannada

This is a narrative about two people who each learnt an unfamiliar language as adults. Both felt that they had to learn the language because the situations they were in demanded it, and both got ample support in acquiring the languages. In this article, I have discussed how, in addition to the felt necessity and the support they received, it is their personal motivation and voluntary effort that led to the learning of the new languag

Contribution of changing galactic cosmic ray flux to global warming

The well established excellent correlation between low-level clouds and primary cosmic ray intensity, which act as nuclei for cloud condensation, clearly shows that a decrease in primary cosmic ray intensity results in lesser low cloud cover. Reduced albedo radiation reflected back into space, due to lesser low cloud cover, results in an increase in the surface temperature on the earth. Extrapolation of the intensity of galactic cosmic radiation using 10Be measurements in deep polar ice as the proxy, clearly shows that the primary cosmic ray intensity has decreased by 9% during the last 150 years, due to the continuing increase in solar activity. We present evidence to show that the radiative forcing component due to the decrease in primary cosmic ray intensity during the last 150 years is 1.1 Wm−2, which is about 60% of that due to CO2 increase. We conclude that the future prediction of global warming presented by IPCC4 requires a relook to take into the effect due to long-term changes in the galactic cosmic ray intensity

A single molecule switch based on two Pd nanocrystals linked by a conjugated dithiol

Tunneling spectroscopy measurements have been carried out on a single molecule device formed by two Pd nanocrystals (dia, $\sim$5 nm) electronically coupled by a conducting molecule, dimercaptodiphenylacetylene. The I-V data, obtained by positioning the tip over a nanocrystal electrode, exhibit negative differential resistance (NDR) on a background M-I-M characteristics. The NDR feature occurs at $\sim$0.67 V at 300 K and shifts to a higher bias of 1.93 V at 90 K. When the tip is held in the middle region of the device, a coulomb blockade region is observed ($\pm\sim$0.3 V).Comment: Accepted in Praman

A digital system for accurate time sector division of a spin stabilized vehicle

Digital system for accurate time sector division of spin stabilized vehicle as used on Pioneer space probe

Machining of Tungsten Heavy Alloy under Cryogenic Environment

AbstractThe machining of tungsten heavy alloy is very difficult as it has high strength and hardness, which requires special cutting tools and cutting process. Though carbide tools are extensively used in conventional cutting, these lead take high machining time and tool failures which cause to decrease in productivity. To overcome the above, special techniques are being practiced in machining of tungsten alloys, one such technique is machining under cryogenic environment. In this paper, liquid nitrogen is used as coolant in machining of tungsten heavy alloys, because it is cost effective, safe, non flammable and environmental friendly gas, in addition to that it cannot contaminate the work piece and no separate mechanism required for disposal. An experimental investigation has been carried out on machining of tungsten heavy alloys by the solid carbide cutting tools under cryogenic and conventional coolants. The material removal rate, surface integrity and cutting forces were studied for both the coolants. The chip morphology also measured for evaluation of shear stress and shear strain. The cryogenic coolant has enhanced the machinability of tungsten heavy alloys. It is observed that the material removal rate was three times higher in cryogenic cooling method when compared with conventional coolant method and the surface finish of the machined surfaces are extremely good and the magnitude of cutting forces are lesser in cryogenic coolant