The visible diffuse reflectance spectrum in relation to the color and crystal properties of hematite

2003 ◽  
Vol 51 (3) ◽  
pp. 309-317 ◽  
Author(s):  
José Torrent ◽  
Vidal Barrón
Keyword(s):  
Diffuse Reflectance ◽  
Reflectance Spectrum ◽  
Diffuse Reflectance Spectrum ◽  
Crystal Properties ◽  
Visible Diffuse Reflectance Spectrum

Quantification of hematite from the visible diffuse reflectance spectrum: effects of aluminium substitution and grain morphology

Clay Minerals ◽  
2011 ◽  
Vol 46 (1) ◽  
pp. 137-147 ◽  
Author(s):  
Q. S. Liu ◽  
J. Torrent ◽  
V. Barrón ◽  
Z. Q. Duan ◽  
J. Bloemendal
Keyword(s):  
Mass Concentration ◽  
Diffuse Reflectance ◽  
Reflectance Spectrum ◽  
Diffuse Reflectance Spectrum ◽  
Grain Morphology ◽  
Characteristic Absorption Band ◽  
Chinese Loess ◽  
Al Substitution ◽  
Soils And Sediments ◽  
Visible Diffuse Reflectance Spectrum

AbstractHematite exists ubiquitously in soils and sediments, and is commonly aluminium (Al)-substituted. This study investigated systematically the effects of Al substitution on the visible diffuse reflectance spectrum (DRS) of hematite by using several sets of synthetic samples. We found that the position and amplitude of the characteristic absorption band of hematite (estimated from the first- and second-order derivative curves of the Kubelka-Munk remission function spectrum derived from the DRS) was significantly affected by the degree of Al substitution as well as by sample grain morphology. Therefore, there are ambiguities in quantifying the degree of Al substitution and the mass concentration of hematite using DRS. Nevertheless, if hematite forms under similar environmental conditions, it is possible to establish a transfer function between the DRS parameters and hematite concentration as discussed here for a Chinese loess-palaeosol sequence.

One new copper iodide coordination polymer directed by 4-pyridyl dithioether ligand: Syntheses, structures, and photocatalysis

2020 ◽  
Vol 19 (3) ◽  
pp. 217-225
Author(s):  
Gui-Ying Qiao ◽  
Su-Min Li ◽  
Yun-Yin Niu
Keyword(s):  
Diffuse Reflectance ◽  
Reflectance Spectrum ◽  
Diffuse Reflectance Spectrum ◽  
Monoclinic Space Group ◽  
Copper Iodide ◽  
Tetrahedral Configuration ◽  
X Ray ◽  
Uv Visible ◽  
Dithioether Ligand ◽  
Visible Diffuse Reflectance Spectrum

One new compound consisting of 1,1-bis(4-pyridylthio)methylene ([Bpytm]) ligand, namely [Bpytm]CuI (1), has been prepared and characterized by IR spectroscopy, solid Uv-visible diffuse reflectance spectrum, and X-ray Powder Diffraction (PXRD). Compound 1 is a 2D MOF and ligand [Bpytm] coordinate with metal ions to form tetrahedral configuration. For compound 1: Crystal system: Monoclinic, Space group: C2/c, a = 13.6671(11), b = 11.6075(11), c = 17.1225(12), α= 90°, β= 93.707(3)°, γ= 90°, V = 2710.6(4) Å3, Z = 8, Dcalc = 2.082 g cm–3. The photocatalytic properties and thermal stability have been researched.

Diffuse Reflectance Spectrum of Ferric Oxide

1970 ◽  
Vol 3 (11-12) ◽  
pp. 297-301 ◽  
Author(s):  
S. P. Tandon ◽  
J. P. Gupta
Keyword(s):  
Ferric Oxide ◽  
Diffuse Reflectance ◽  
Reflectance Spectrum ◽  
Diffuse Reflectance Spectrum

Diffuse reflectance spectrum of some Nd3+ aromatic acids

1974 ◽  
Vol 15 (5) ◽  
pp. 787-789
Author(s):  
S.P. Tandon ◽  
P.P. Vaishnava ◽  
R.C. Mathur
Keyword(s):  
Diffuse Reflectance ◽  
Reflectance Spectrum ◽  
Diffuse Reflectance Spectrum ◽  
Aromatic Acids

Measurement of Diffuse Reflectance Spectrum of Biological Material with Single Integrating-Sphere

2011 ◽  
Vol 321 ◽  
pp. 252-255
Author(s):  
Lian Shun Zhang ◽  
Lei Fu ◽  
Kong Yang Zhao
Keyword(s):  
Biological Material ◽  
Diffuse Reflectance ◽  
Reflectance Spectrum ◽  
Diffuse Reflectance Spectrum ◽  
Experimental System ◽  
Integrating Sphere ◽  
Light Sources ◽  
Human Breast ◽  
Human Breast Tissue ◽  
Halogen Light

Detection of interactions between light and biological material can be used to characterize the optical properties of the biological material. The purpose of this paper is to develop a method that measures the diffuse reflectance spectrum of biological material with single integrating-sphere. The experimental system incorporated a DH-2000 Deuterium Tungsten Halogen Light Sources, USB4000-VIS-NIR Miniature Fiber Optic Spectrometer and an integrating-sphere. Intralipid and ink were used to mimic scattering and absorbing properties of biological material in the tested sample. Total of 30 sample representing of normal and malignant human breast tissue were measured. The measured optical reflectance spectrums with different scattering and absorbing properties were analyzed. The result showed that the diffuse reflectance spectrums of normal and malignant biological material are different in intensity.

Spectrophotometric Studies on Sb(III) in Hydrochloric Acid Solutions

1975 ◽  
Vol 53 (6) ◽  
pp. 888-893 ◽  
Author(s):  
John Milne
Keyword(s):  
Raman Spectrum ◽  
Hydrochloric Acid ◽  
Diffuse Reflectance ◽  
Reflectance Spectrum ◽  
Diffuse Reflectance Spectrum ◽  
Equilibrium Mixture ◽  
Ultraviolet Spectroscopy ◽  
Acid Solutions ◽  
Hydrochloric Acid Solutions ◽  
Solubility Studies

Ultraviolet spectroscopy confirms the findings of solubility studies that Sb(III) in 3–12 M hydrochloric acid solutions is present as an equilibrium mixture of SbCl4− and SbCl63− ions. In the presence of H2SO4 a further equilibrium with the SbCl3(HSO4)− ion is found. The spectrum of the SbCl63− ion in solution is unlike the diffuse reflectance spectrum of this anion in Co(NH3)6SbCl6 but is similar to that in K3SbCl6. The Raman spectrum of 2 M SbCl3 in 2.8 M hydrochloric acid is shown to be due to the SbCl4− ion and the spectrum is assigned under C2υ symmetry. The Raman spectrum of the SbCl63− ion in solution is discussed.

scholarly journals Adsorption-Photometric and Test-Determination of Fe(III) in Natural Water Using Silica Lyer-by-Lyer Modified with Polyhexamethylene Guanidine and Ferron

2020 ◽  
pp. 349-362
Author(s):  
Svetlana L. Didukh-Shadrina ◽  
Olga V. Buyko ◽  
Vladimir N. Losev
Keyword(s):  
Natural Water ◽  
Mineral Water ◽  
Diffuse Reflectance ◽  
Reflectance Spectrum ◽  
Diffuse Reflectance Spectrum ◽  
Photometric Determination ◽  
Test Method ◽  
Test Determination ◽  
Polyhexamethylene Guanidine

Silica based adsorbent sequentially modified with polyhexamethylene guanidine and 7-iodine-8-hydroxyquinoline-5-sulfonic acid (Ferron) was proposed for adsorption-photometric and test-determination of Fe(III) in natural water. During adsorption of Fe(III) from solutions with pH 2.0-3.5 adsorbent became green colored. Formation of green-colored surface complex of Fe(III) with Ferron with the maximum in diffuse reflectance spectrum at 600 nm was used for developing the procedure of its adsorption-photometric determination. Detection limit calculated by 3s-criterion was 0.03 μg/0.1 g of adsorbent (3 μg/L if the adsorption was carried out from 10 mL of solution); the analytical range was 10 – 220 μg/L. Test-method was proposed for quick visual determination of Fe(III) in natural water in the variant of test-scale. Developed procedures were tested for determination of iron in natural river water of Krasnoyarskii kray and mineral water “Zagorie”

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