We have taken optical and infrared observations during the 2002 outburst of the soft X-ray transient, 4U 154347. A secondary maximum occurs in the lightcurves during the outburst decline. This feature is much stronger at infrared wavelengths than optical. We have applied single blackbody, multicolor blackbody and broken-power law models to the optical/infrared spectral energy distribution of th...

We studied the UV-vis absorption and fluorescence in solution/solid states of [n]cycloparaphenylene ([n]CPP: n = 9, 12, 14, 15, and 16), and conducted theoretical studies to better understand the experimental results. The representative experimental findings include (i) the most intense absorption maxima (λ(abs1)) display remarkably close values (338-339 nm), (ii) the longest-wavelength absorpt...

In this paper, the fluorescence behaviour of nano colloids of ZnO has been studied as a function of the excitation wavelength. We have found that excitation at the tail of the absorption band gives rise to an emission that shifts with the change of the excitation wavelength. The excitation wavelength dependent shift of the fluorescence maximum is measured to be between 60 and 100 nm. This kind ...

Light enters the eye, is focused by the cornea, passes through the variable-diameter iris, is further focused by the lens, and strikes the light-sensitive receptors of the retina in the back of the eye. The photoreceptors of the retina can be divided into two basic categories: rods and cones. At normal light levels, cones dominate the initial response to light, resulting in photopic vision. Thr...

A wavelength-switchable single-longitudinal-mode thulium-doped fiber laser using a sampled Bragg grating is proposed in this study. The can be switched between three single-wavelength and dual-wavelength modes of operation. For the mode operation, maximum power wavelength fluctuations 50 min were ±0.404 dB ±0.01 nm, linewidths at wavelengths 0.39, 1.88, 0.89 kHz, respectively. 20 ±0.926 ±0.03 w...

A multi-wavelength solar radiometer has been used to monitor the directly transmitted solar radiation at discrete wavelengths spaced through the visible and near-infrared wavelength regions. The relative irradiance of the directly transmitted sunlight at each wavelength was measured during the course of each cloud-free day, from which the total optical depth of the atmosphere was determined usi...

We isolated and characterized a green fluorescent protein (GFP) from the sea cactus Cavernularia obesa. This GFP exists as a dimer and has absorption maxima at 388 and 498 nm. Excitation at 388 nm leads to blue fluorescence (456 nm maximum) at pH 5 and below, and green fluorescence (507 nm maximum) at pH 7 and above, and the GFP is remarkably stable at pH 4. Excitation at 498 nm leads to green ...

A high power bottom-emitting InGaAs/GaAsP vertical-cavity surface-emitting laser with a large aperture (400 μm diameter) is described. The device has been fabricated by using oxidation confinement technology. The device threshold current is 610 mA, and the maximum output power is up to the watt regime (1.42 W) at room temperature (24 ◦C) with a pulse condition (pulse width of 50 μs, repetition ...

In the present paper, the recent applications of optical parametric amplifiers (OPAs) in hybrid wavelength division multiplexing (WDM)/time division multiplexing (TDM) local area passive optical networks have been modeled and parametrically investigated over wide range of the affecting parameters. Moreover, we have analyzed the ability of the hybrid WDM/TDM Passive optical networks to handle a ...