(NASA/GSFC) was responsible for the design, development, and operation of the Cosmic Background Explorer (COBE). GSFC was also responsible for the development of the analysis software and for the production of the mission data sets. The COBE program was supported by the Astrophysics Division of NASA's Office of Space Science and Applications. ABSTRACT The photometric errors of the external cali...

Nowadays, hydrogen has attracted significant attention as a next generation clean energy source. Hydrogen is highly flammable, so detection of hydrogen gas is required. Gold nanoparticle based localized surface plasmon resonance (LSPR) is an advanced and powerful sensing technique, which is well known for its high sensitivity to surrounding refractive index change in the local environment. We p...

A spectrophotometer cuvet is described which is emptied by suction without removal from the instrument. The use of this cuvet saves time and minimizes the chance of breakage. Data from C " measurements and absorbances of a dye solution show minimal retention error from successive specimens. expended in determining the absonbances of a large series of individual samples in a spectrophotometer ca...

This study aimed to evaluate the physicochemical characteristics and mineral contents of dried extract Averrhoa bilimbi its antioxidant antibacterial properties. Dried extracts leaves powder A. were analysed for properties compositions. The capacities determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay disc diffusion method respectively. functional groups from active compounds identified F...

In this paper, CuO-ZnO nanocomposite was synthesized and its photocatalytic dye degradation ability from colored wastewater was studied. Basic Red 18 (BR18) and Basic Violet 16 (BV16) were used as model dyes. The characteristics of CuO-ZnO of were investigated using Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM) and X-ray diffraction (XRD). Photocatalytic dy...

An inexpensive photoreactor using LED light sources and a fibre-optic CCD spectrophotometer as a detector was built by designing a special cell holder for standard 1.000 cm cuvettes. The use of this device was demonstrated by studying the aqueous photochemical reaction of 2,5-dichloro-1,4-benzoquinone. The developed method combines the highly quantitative data collection of CCD spectrophotomete...

Problem statement: Systematic series of ZnO-TeO2 glasses with mole fraction of 0.10-0.40 ZnO content with an interval of 0.05 were studied to obtain their physical and optical properties. Approach: All the glass samples were synthesized by rapid melting quenching method under controlled conditions, while their refractive indices (n) were measured by the EL X-02C high precision ellipsometer. The...

and – 2 – ABSTRACT Observations of ultraluminous infrared galaxies (ULIRGs) with an achieved resolution approaching the diffraction limit in the mid-infrared from 8-25 µm using the Keck Telescopes are reported. We find extremely compact structures, with spatial scales of < 0.3 ′′ (diameter) in six of the seven ULIRGs observed. These compact sources emit between 30% and 100% of the mid-infrared ...