A characteristic spectral emission is observed in vegetation chlorophyll under excitation by solar radiation. This emission, known as solar-induced chlorophyll fluorescence, occurs in the red and near infra-red spectral regions. In this paper a new methodology for the estimation of solar-induced chlorophyll fluorescence from spaceborne and airborne sensors is presented. The fluorescence signal ...

We report in this communication the two-photon absorption (TPA)-induced room-temperature lasing performance of ZnO nanowires. Under femtosecond pulse-excitation at lambda = 700 nm in the infrared regime, a remarkably low threshold of 160 microJ/cm(2) was observed for the TPA-induced lasing action, which is of the same order of magnitude as that measured for the linear lasing process. Time-resol...

The relation between the γ-ray and the emission line luminosities for a sample of 36 γ-ray loud blazars is investigated; an apparent correlation between them, Lγ ∝ L 0.69±0.11 Line , with a correlation coefficient r = 0.741 and a chance probability of p = 1.9× 10, is found. It is found, however, that there is no intrinsic correlation between them: the apparent correlation is due to the redshift...

We showed that if the non-thermal emission from the Galactic center in the range 14− 40 keV is due to inverse bremsstrahlung emission of subrelativistic protons, their interactions with hot and cold fractions of the interstellar medium are equally important. Our estimation show that about 30% of the total non-thermal flux from the GC in the range 14− 40 keV is generated in regions of cold gas w...

As molecular labels for cells and tissues, fluorescent probes have shaped our understanding of biological structures and processes. However, their capacity for quantitative analysis is limited because photon emission rates from multicolour fluorophores are dissimilar, unstable and often unpredictable, which obscures correlations between measured fluorescence and molecular concentration. Here we...

We detail our efforts toward the selective detection of cyclic ketones, e.g. cyclohexanone, a component of plasticized explosives. Thin films comprised of a conjugated polymer are used to amplify the emission of an emissive receptor via energy transfer. We propose that the energy transfer is dominated by an electron-exchange mechanism to an upper excited state of the fluorophore followed by rel...

Electrogenerated chemiluminescence (ECL) of CdSe quantum dots (QDs) dispersed in aqueous solution was studied with bare electrode. The ECL emission was observed at -1.4 V vs. Ag/AgCl and the ECL spectrum peak is similar to that of the defect photoluminescence (PL) spectrum, indicating the surface defects played a critical role in the emission process. The experiment results suggested that disso...

This paper examines the long run cointegrating relation and short run dynamics among carbon emissions, energy consumption, economic growth, urbanization, financial development and openness to trade in Bangladesh by using autoregressive distributed lag (ARDL) bounds testing approach of cointegration. Empirical results for Bangladesh over the period 1975-2010 suggest an evidence of a long-run rel...