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The analysis of spectra is fundamental to our modern understanding of wave optics and color perception. Every student should have the opportunity to conduct their own optical emissions experiments. Since spectrometers are expensive and accurate calibration is necessary to achieve high quality spectra, we developed a remote lab for optical spectrometry. The VirtualRemoteLab combines the remote lab...
There is an increasing interest in the classification of vegetable oils as an effective means to examine authenticity and to detect possible adulteration of extra virgin olive oils with seed oils or low-quality olive oils. Classical methods such as, Gas Chromatography, High Performance Liquid Chromatography, Fourier Transform Infrared and Nuclear Magnetic Resonance, are too expensive for widespread...
The surfaces of the large uranian satellites are characterized by a mixture of H2O ice and a dark, potentially carbon-rich, constituent, along with CO2 ice. At the mean heliocentric distance of the uranian system, native CO2 ice should be removed on timescales shorter than the age of the Solar System. Consequently, the detected CO2 ice might be actively produced. Analogous to irradiation of icy moons...
The Panoramic Camera (Pancam) on the Mars Exploration Rovers Spirit and Opportunity acquired visible/near-infrared (432–1009nm) multispectral observations of soils and rocks under varying viewing and illumination geometries. Data retrieved from these images were modeled using radiative transfer theory to study the microphysical and surface scattering nature of materials at both sites. Nearly 57,000...
Charge transfer complexes of loperamide hydrochloride (LOP.HCl) and trimebutine (TB) drugs as electron donor with 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), tetracyanoethylene (TCNE) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) as π-acceptors in acetonitrile were investigated spectrophotometrically to determine the cited drugs in pure and dosage forms. The reaction gives highly coloured complex...
We report a comprehensive review of the UV–visible spectrum and rotational lightcurve of Vesta combining new observations by Hubble Space Telescope and Swift Gamma-ray Burst Observatory with archival International Ultraviolet Explorer observations. The geometric albedos of Vesta from 220nm to 953nm are derived by carefully comparing these observations from various instruments at different times and...
Based on the spectrometry, a new method by derivative visible spectrophotometry for the determination of atrazine was built which was called P-aminoacetophenone Spectrophotometric. Results showed that this method presented favorable accuracy and precision within the range of 0.01 0.16mg/L, and R2=0.9997%. Moreover, the optimal operating condition of measurement method was fixed as maximum absorption=464nm;...
Fast classification of soil with different texture is essential for site-specific application of different inputs into farmland. Total 203 soil samples with five textures were collected from Silsoe Experimental Farm, Cranfield University, England. Using a Vis/NIR spectrophotometer (Tech5, Germany), spectra of soil samples were recorded for the study. Amongst the pre-processing methods, smoothing with...
Measurements of the disk-integrated reflectance spectrum of Mercury and the Moon have been obtained by the MESSENGER spacecraft. A comparison of spectra from the two bodies, spanning the wavelength range 220–1450nm, shows that the absolute reflectance of Mercury is lower than that of the nearside waxing Moon at the same phase angle with a spectral slope that is less steep at visible and near-infrared...
We have extended our earlier work on space weathering of the youngest S-complex asteroid families to include results from asteroid clusters with ages <10 6 years and to newly identified asteroid pairs with ages <5×10 5 years. We have identified three S-complex asteroid clusters amongst the set of clusters with ages in the range 10 5–6 years—(1270) Datura, (21509) Lucascavin...
Reflectance spectra in visible and near-infrared wavelengths of 97 nominal members of the Eunomia asteroid family have been obtained and analyzed. According to these investigations, 94% of the observed dynamic family members belong to the Tholen S-class, only 4% to the C-class and 2% to the M-class. The S-asteroids are believed to be “genetic” members of the Eunomia family and thus are fragments of...
In this study, artificial antigens for Bensulfuron-methyl (BSM) were prepared by means of two-step procedure of glutaraldehyde method. The hapten BSM was covalently attached to ovalbumin to synthesis immunogen (BSM-OVA), and hapten Benzyl sulfonamide (BS) was linked to BSA to prepare coating antigen (BS-BSA). The conjugates were identified by UV spectrophotometry and SDS-PAGE. After immunized with...
Arsenic compounds are highly toxic and the toxicity of trivalent arsenic compounds is more powerful than others. There are many ways of its determination. This article describes the determination of trace Arsenic in Qin River by Paper Absorption Spectrophotometry. The result indicate that the limit of detection of this method is 0.001 mg/L, the standard deviation is 0.0007 mg/L and the mark-on recovery...
Reflectance spectrophotometry is the most established and widely used objective technique for the assessment of port-wine stain (PWS) skin, and has been applied extensively in other dermatological applications. To date, no review has been published regarding the different spectrophotometric devices used on PWS skin. This paper comprises such a review, introducing the reader to the relevant background...
An innovative fiber optic setup for the scattering-free absorption spectroscopy of liquids is presented. It makes use of an integrating sphere that contains the sample under test, coupled to a fiber optic supercontinuum source and to a fiber optic spectrometer. The highly-bright broadband light shining on the sphere's surface is diffusely reflected and collected by the fiber-coupled spectrometric...
A novel spectrophotometric method for the determination of trace amount of Chromium (VI) by tri-hydroxyl phenylfluorone (THPF) in the microemulsion medium has been developed. All the variables were studied in order to optimize the reaction conditions. At pH = 5.82, Cr(VI) reacts with THPF to form a 1 : 2 complex, which has a maximum absorption at 560 nm with a molar absorptivity of 8.99times104 L/mol/cm...
A new sensitive and selective catalytic kinetic spectrophotometric method for the determination of trace amount of palladium (II) has been developed. The method is based on the catalytic effects of palladium (II) on the reduction reactions of Poniacyl Carmine 2B (PC 2B) by sodium dihydrogen hypophosphite (NaH2PO2) in sulfuric acid medium. The optimal reaction conditions are PC 2B (1.0 times 10-3 mol/L)...
A highly sensitive and selective spectrophotometric method is proposed for the determination of trace lead in food. The method is based on the reaction of lead(II) with a new analytical reagent trihydroxyphenylfluorone (TH-PF). TH-PF reacts with lead(II) and form a stable 1 : 2 complex at pH 10.40. Its apparent molar absorption coefficient and Sandell's sensitivity at 580 nm are 4.56 times 104 L/mol/cm...
In the present work, a new imaging device for multi spectral analysis in the visible range is presented, together with its own performances and an example of its application. The instruments can be used to acquire photometric and colorimetric characteristics of wide surfaces in quick and easy way. It is composed by a scientific grade CCD camera and a tunable narrow band filter bench; it acts as a...
Titan is known to have a young surface. Here we present evidence from the Cassini Visual and Infrared Mapping Spectrometer that it is currently geologically active. We report that changes in the near-infrared reflectance of a 73,000 km 2 area on Titan (latitude 26° S, longitude 78° W) occurred between July 2004 and March of 2006. The reflectance of the area increased by a factor of two between...
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