CHLOROPHYLL ANALYSIS OF WHOLE RAPESEED KERNELS BY NEAR INFRARED REFLECTANCE

1982 ◽  
Vol 62 (4) ◽  
pp. 875-884 ◽  
Author(s):  
RUSSELL TKACHUK ◽  
F. D. KUZINA

Chlorophyll content was determined in whole rapeseed samples, from Regent and Candle cultivars, by using a reflectance technique in the visible and near infrared region. Chlorophyll content was estimated with good accuracy when predicted results for 42 samples of Regent, 37 samples of Candle and 79 samples for both cultivars combined were compared with standard laboratory results. For Regent, a multiple correlation coefficient (R) of 0.944 and a standard error of estimate (Sy) of 4.7 were obtained when reflectance was measured at six wavelengths. For Candle, R = 0.963 and Sy = 4.4, using another six wavelengths. For both cultivars combined, R = 0.939 and Sy = 4.8, again using a different set of six wavelengths. Wavelengths for predicting chlorophyll were selected from the 630-to 754-nm visible region, and from the 1640- to 2176-nm near infrared region. This reflectance method described for whole rapeseed is rapid, involves no sample preparation, and leaves the seed intact and available for other uses.

Author(s):  
Berta Carrión-Ruiz ◽  
José Luis Lerma

This paper tackles principal component analysis (PCA) in images that include wavelengths between 380-1000 nm. Our approach is focussed on taking advantage of the potencial of ultraviolet and infrarred images, in combination with the visible ones, to improve documentation process and rock art analysis. In this way, we want to improve the discrimination between pigment and support rock, and analyse the spectral behaviour of rock art paintings in the ultraviolet and infrared regions. Three images were used, one image from the ultraviolet (UV) region, one from the visible region (VIS) and another one from the near infrared region (NIR). Optical filters coupled to the camera optics were used to take the images. These filters capture specific wavelengths excluding radiation that we are not interested in registering. Finally, PCA is applied to the acquired images. The results obtained demonstrate the PCA usefulness with imagery in this field and also it is possible to extract some conclusions about the correspondent paint pigments.http://dx.doi.org/10.4995/CIGeo2017.2017.6597


2010 ◽  
Vol 126-128 ◽  
pp. 935-939 ◽  
Author(s):  
Min Hu ◽  
Ying Liu

A series of Ti/TiN multilayer films were prepared by reactive DC magnetron sputtering onto Si(111) substrates. The resistivity and optical reflectance of these thin films were measured as a function of the modulated, multilayered thickness and the number of layered structures. The resistivity decreased with increase in the number of layers in the film up to 4 layers. The reflectance in the near infrared region increased with increase in layer thickness but after a certain thickness, the change in reflectance was minimal. An optimum thickness of 25 nm for the modulated film realized a maximum of 0.829 in the near infrared reflectance. With the number of layers greater than 15, an interfacial layer of Ti2N was observed.


1986 ◽  
Vol 41 (1) ◽  
pp. 25-31 ◽  
Author(s):  
M. Bruns ◽  
W. Preetz

The first carbonyl compound of quadrivalent osmium [OsCl5(CO)]- is prepared by chlorination of trans-[OsX4(CO)2]- (X = Br, I) dissolved in CH2Cl2. It is reduced immediately by Br- and I- to give [OsCl5(CO)]2-. The standard potential [OsCl5(CO)]-/ [OsCl5(CO)]2- in acetonitrile referred to the saturated mercury-mercurous sulphate electrode is 0.623 V. The IR and Ra bands of [OsCl5(CO)]- are assigned according to point group C4v. Compared with the corresponding Os(III) complex there is a shift to higher frequencies of ν(CO) and ν(OsCI) of about 170 and 25 cm-1, whereas ν(OsC) and δ(OsCO) are lowered by 158 and 110cm-1, respectively. The electronic absorption spectrum shows six d - d bands coupled with vibrations in the near infrared region. The O - O transitions are calculated from the vibrational fine structure, taking into consideration shifts by 13C isotopic substitution. The lowest levels are confirmed by peaks in the electronic Raman spectrum. From the estimated Racah parameter B = 280 cm-1 the low nephelauxetic ratio β55 = 0.41 is deduced indicating the high covalency in [OsCl5(CO)]-. Owing to the strong oxidizing character of Os(IV) the intensive charge transfer transitions in the visible region are shifted bathochromicly by about 4000 cm1 in relation to corresponding bands of [OsCl5(CO)]2-.


1983 ◽  
Vol 38 (6) ◽  
pp. 680-686 ◽  
Author(s):  
W. Preetz ◽  
M. Bruns

Abstract (TEA)[OSCl6] is formed quantitatively by heating solid trans-(TEA)[OsX4(CO)2] (X = Br, I) in a stream of chlorine at 120 °C, and can be purified by recrystallisation from CH2Cl2 without decomposition. It is reduced immediately by acetone, methanol, Cl-, Br-, I- to give [OsCl6]2-. The standard potential [OsCl6]-/[OsCl6]2- in acetonitrile referred to the saturated mercury-mercurous sulphate electrode is 0.840 V. The IR and Ra bands of (TEA)[OsCl6], assigned according to point group Oh, are shifted to higher frequencies compared with (TEA)2[OsCl6]. The excitation at 488.0 nm gives a resonance Raman spectrum exhibiting 6 overtones of vi and combination tones up to 4ν1 + v5. The electronic absorption spectrum shows five spin-forbidden intraconfigurational transitions coupled with odd vibrational modes in the near infrared region. The spin-allowed 4A2g → 4T2g,4T1g-transitions are observed at 347 and 305 nm. The excited levels can be fitted with the parameters ⊿ = 28500 cm-1, B = 340 cm-1, ξ = 2500 cm-1 , allowing to calculate the nephelauxetic ratio β55 to 0.47. In the visible region extensive charge transfer transitions are observed. Based on the strong oxidizing character of Os(V) there is a bathochromic shift of corresponding bands of [OsCl6]- in relation to [OsCl6]2- of about 6600 cm-1 and to the isoelectronic [ReCl6]2- of about 13700 cm-1, respectively. From πt1u→dt2g the optical electronegativity is calculated to Xopt(Osv) = 2.49.


2003 ◽  
Vol 07 (02) ◽  
pp. 131-136 ◽  
Author(s):  
Tasuku Komori ◽  
Yutaka Amao

The dye-sensitized solar cell (DSSC) using visible and near-infrared sensitization of nanocrystalline TiO 2 films using a series of four aluminum phthalocyanines was developed and its photoelectrochemical properties were investigated. By using aluminum 2,9,16,23-tetrakis(phenyl-thio)-29H,31H-phthalocyanine chloride adsorbed on a nanocrystalline TiO 2 film electrode, the I SC , V OC , FF , P max and η values were largest compared with the other DSSCs using aluminum phthalocyanines. For all the DSSCs using aluminum phthalocyanines, IPCE values at near-infrared region (700 nm) are larger than those at visible region (500 nm). Thus, the DSSC using near-infrared sensitization of nanocrystalline TiO 2 film by aluminum phthalocyanines was developed.


1987 ◽  
Vol 33 (4) ◽  
pp. 502-506 ◽  
Author(s):  
G Koumantakis ◽  
F J Radcliff

Abstract We describe use of near-infrared reflectance spectroscopy (NIRRS) to estimate the amount of fat in feces, for diagnosis of steatorrhea. After sample homogenization, the spectrum of the fecal homogenate is scanned over the near-infrared region. Assay of 94 samples of feces having a known concentration of fat showed the appropriate wavelengths for the NIRRS procedure to be 1734, 1778, 1818, 2270, and 2310 nm. The reflectance output of 47 fecal samples subsequently measured at these wavelengths was used to compute the reflectance scaling factors (F values) by the instrument's microprocessor. Assay of fat content in a further 124 fecal samples, by both hydrolysis/titration (J Biol Chem 1949;177:347) and the NIRRS procedure at the wavelengths and corresponding F values previously determined, gave results that correlated highly satisfactorily. However, the NIRRS procedure demonstrated much better precision.


2015 ◽  
Vol 2015 ◽  
pp. 1-8
Author(s):  
Xin Zhou ◽  
Shuangchun Wen ◽  
Bin Tang ◽  
Diwu Yang ◽  
Jun He

The plasmon resonance behavior in Ag-Au split-ring resonator (SRR) heterogeneous dimer array has been investigated numerically by using the finite difference time domain (FDTD) method. The resonance dips were tuned with the metallic SRR dimer arrays constituted by different metals. For the Ag-Au heterogeneous SRRs dimer array, with the arms of metallic cross lengths increasing, the resonance dips in the visible region red shifted but the locations of resonance modes in the near-infrared region kept immovability. On the contrary, the locations of resonance dips in the visible region kept immovability but the resonance modes in the near-infrared region red shifted obviously with the air cuts widths decreasing. The whole resonance dips exhibited a red-shift as the environmental dielectric constants increase. The electric and magnetic field distributions of certain resonance wavelengths were also investigated.


Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2023 ◽  
Author(s):  
Haoguo Yue ◽  
Lingqian Kong ◽  
Bo Wang ◽  
Qing Yuan ◽  
Yan Zhang ◽  
...  

Three soluble conjugated polymers, named BEDPP, FLDPP, and CADPP, were prepared through the Suzuki polymerized reaction, and employed benzene (BE), fluorene (FL), and carbazole (CA) as the donor units, respectively. The electron-deficient molecule 2,5-bis-(2-octyldodecyl)-3,6-bis-(5-bromo-thiophene)-pyrrole[3-c]pyrrole-1,4-diketone(DPP) was introduced and used as the acceptor unit. The properties of these three copolymers were studied by a series of detailed characterization analysis, including X-ray photoelectron spectroscopy (XPS), colorimetry, electrochemical measurements, spectroelectrochemistry, kinetics, quantitative calculation, and thermogravimetric (TG) analysis, etc. The results revealed that BEDPP displayed a blue color in the neutral state and a light brown color in the oxidized state, FLDPP exhibited a cyan color in the neutral state and a gray color in the oxidized state, while CADPP displayed pure blue color in the neutral state and a light gray color in the oxidized state. All these polymers possess narrow optical band gaps lower than 1.80 eV and satisfactory thermal stability. The kinetic characterization showed that the optical contrasts (ΔT%) in the near-infrared region were superior to the visible region. The optical contrasts of BEDPP, FLDPP, and CADPP are 41.32%, 42.39%, and 45.95% in the near-infrared region, respectively, which made them a good application prospect in the near-infrared region. Amid the three polymers, CADPP has the highest coloration efficiency (around about 288 cm2·C−1) and fast switching times (0.77 s in the coloring process and 0.52 s in the bleaching process) in the visible region, and the comprehensive performance of CADPP can be comparable to that of the reported D-A (Donor-Acceptor) type blue color polymers. In general, based on the good performances and the stable neutral blue color, the three polymers had profound theoretical significance for the development of electrochromic material and the completion of the RGB (Red, Green, Blue) color space.


RSC Advances ◽  
2018 ◽  
Vol 8 (25) ◽  
pp. 14072-14083 ◽  
Author(s):  
Hidemitsu Uno ◽  
Takayuki Honda ◽  
Manami Kitatsuka ◽  
Shogo Hiraoka ◽  
Shigeki Mori ◽  
...  

Benzene-fused bis(acenaphthoBODIPY)s prepared by retro-Diels–Alder reaction of bicyclo[2.2.2]octadiene-fused precursors showed strong absorption bands in the near-infrared region and very weak absorptions in the visible region.


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