Ultraviolet cometary spectrophotometry

During the 13 shifts dedicated to observations of Comet Bradfield (including the two European shifts), five high dispersion exposures were obtained with the LWR camera, 27 low dispersion images with the LWR camera, and 36 low dispersion images with the SWP camera of which 5 were observations of the geocoronal background and 4 were taken in a serendipity mode while the nucleus of the comet was centered on the large aperture of the LWR camera

Spectrophotometry of comets

Photoelectric spectrophotometric- and image tube equipped spectrographic-studies on comets are used to formulate a new model for the cometary nucleus that is physically similar to the icy-conglomerate. Absolute flux distributions of the principal spectral features for five comets of different compositions and heliocentric distances were evaluated. Comparison of visible and infrared brightnesses was used to calculate the optical albedos of observed particles

Multi-filter spectrophotometry simulations

To complement both the multi-filter observations of quasar environments described in these proceedings, as well as the proposed UBC 2.7 m Liquid Mirror Telescope (LMT) redshift survey, we have initiated a program of simulated multi-filter spectrophotometry. The goal of this work, still very much in progress, is a better quantitative assessment of the multiband technique as a viable mechanism for obtaining useful redshift and morphological class information from large scale multi-filter surveys

Spectrophotometry for cerebrospinal fluid pigment analysis

The use of spectrophotometry for the analysis of the cerebrospinal fluid (CSF) is reviewed. The clinically relevant CSF pigments--oxyhemoglobin and bilirubin--are introduced and discussed with regard to clinical differential diagnosis and potentially confounding variables (the four T's: traumatic tap, timing, total protein, and total bilirubin). The practical laboratory aspects of spectrophotometry and automated techniques are presented in the context of analytical and clinical specificity and sensitivity. The perceptual limitations of human color vision are highlighted and the use of visual assessment of the CSF is discouraged in light of recent evidence from a national audit in the United Kingdom. Finally, future perspectives including the need for longitudinal CSF profiling and routine spectrophotometric calibration are outlined

An analysis of the shapes of interstellar extinction curves. VII Milky Way spectrophotometric optical-through-ultraviolet extinction and its R-dependence

We produce a set of 72 NIR-through-UV extinction curves by combining new Hubble Space Telescope/STIS optical spectrophotometry with existing International Ultraviolet Explorer spectrophotometry (yielding gapless coverage from 1150 to 10000 ?) and NIR photometry. These curves are used to determine a new, internally consistent NIR-through-UV Milky Way mean curve and to characterize how the shapes of the extinction curves depend on R(V). We emphasize that while this dependence captures much of the curve variability, considerable variation remains that is independent of R(V). We use the optical spectrophotometry to verify the presence of structure at intermediate wavelength scales in the curves. The fact that the optical-through-UV portions of the curves are sampled at relatively high resolution makes them very useful for determining how extinction affects different broadband systems, and we provide several examples. Finally, we compare our results to previous investigations

CSPOB-Continuous Spectrophotometry of Black Holes

The goal of a small and dedicated satellite called the "Continuous Spectro-Photometry of Black Holes" or CSPOB is to provide the essential tool for the theoretical understanding of the hydrodynamic and magneto-hydrodynamic flows around black holes. In its life time of about three to four years, only a half a dozen black holes will be observed continuously with a pair of CSPOBs. Changes in the spectral and temporal variability properties of the high-energy emission would be caught as they happen. Several important questions are expected to be answered and many puzzles would be sorted out with this mission.Comment: 4 Pages, 3 Figures, Proceeding of the 2nd Kolkata Conference on "Observational Evidence for the Black Holes in the Universe", Published in AIP, 200

Silicon photonics for on-chip spectrophotometry

Silicon and Silicon Nitride photonics arc on their way to open the route towards integrated on-chip spectropholometers, Cost, miniaturization, miniaturization, hut also performance advantages ace at the origin of their potential We will discuss several integrated on-chip spectropholometers that are on the eve of commercial take up

Determination of Hexavalent Chromium (Cr(VI)) Concentrations via Ion Chromatography and UV-Vis Spectrophotometry in Samples Collected from Nacogdoches Wastewater Treatment Plant, East Texas (USA)

The concentration of hexavalent chromium (Cr(VI)), a toxic environmental pollutant and carcinogen, was determined in samples collected from Nacogdoches Wastewater Treatment Plant (NWWTP) using ion chromatography and UV-visible spectrophotometry (IC, UV-Vis). On reaction with 1,5-diphenylcarbazide (DPC) Cr+6 forms a 1,5-diphenylcarbazide-Cr(VI) complex, which is then analyzed at 530nm and 540nm, respectively. Via ion chromatography Cr(VI) concentrations were in the range of 0.00190 ± 0.0020 and 0.0010 ± 0.0006ppm at the influent and effluent, respectively. With the use of standard addition wastewater samples were spiked with a 0.5ppm Cr(VI) standard of various amounts and subsequently analyzed with UV-Vis spectrophotometry. The spiked concentrations gave Cr(VI) concentrations in the range of 0.0090 ± 0.0060ppm and 0.0040 ± 0.0061ppmattheinfluentandinfluentwastewater,respectively.ThedeterminedCr(VI)concentrationsthroughtheion chromatography and UV-Vis spectrophotometry are below the maximum USEPA contaminant concentration of 0.1ppm. From theanalysis,theNWWTPefficientlyremovesCr(VI)beforedischargeintotheenvironmentthroughLaNanaCreek.Theremoval efficiencyforCr(VI)wasdeterminedtobe ≥92.8%alongthewastewatertreatmentstagesfromtheinfluent(aerationstage)tothe effluentstagespriortodischargeintotheLaNanaCreek