Lignocellulosic biomass from sugarcane (
Saccharum
spp. hybrids) could potentially be a major feedstock for second-generation biofuel production. Consequently, selecting sugarcane varieties with ...favorable biomass characteristics, typically less enzymatic recalcitrance and better saccharification yield without sugar-yield penalty, will be important in sugarcane breeding. Economical and high-throughput techniques for profiling the major biomass components of this complex system will facilitate selection of clones with ideal lignocellulosic composition from large numbers of genotypes in breeding programs. We used a combined high-throughput profiling approach to evaluate the biomass composition of samples from a sugarcane germplasm collection. This employed near-infrared (NIR) spectroscopy for fiber characterization and high-performance liquid chromatography (HPLC) for determining the sugar content in juice. The results for 331 samples, from a diverse sugarcane population of 186 genotypes, derived from 143 parents of different genetic backgrounds, showed that high-quality NIR spectroscopic predictions were feasible for cellulose, hemicellulose, lignin, and extractives values in fiber, and sugars in juice were suitably analyzed by HPLC. The analysis of total biomass indicated that this NIR- and HPLC-based high-throughput method allowed a robust phenotypic assessment of a large number of samples for the key biomass traits in the sugarcane system, including total dry biomass, fiber, sugar content, and theoretical ethanol yields, and could potentially become the method of choice for sugarcane germplasm screening in breeding programs targeting the support of biofuel production.
The Raman spectrum of atelestite Bi2O(OH)(AsO4), a hydroxy-arsenate mineral containing bismuth, has been studied in terms of spectra-structure relations. The studied spectrum is compared with the ...Raman spectrum of atelestite downloaded from the RRUFF database. The sharp intense band at 834 cm(-1) is assigned to the ν1 AsO4(3-) (A1) symmetric stretching mode and the three bands at 767, 782 and 802 cm(-1) to the ν3 AsO4(3-) antisymmetric stretching modes. The bands at 310, 324, 353, 370, 395, 450, 480 and 623 cm(-1) are assigned to the corresponding ν4 and ν2 bending modes and BiOBi (vibration of bridging oxygen) and BiO (vibration of non-bridging oxygen) stretching vibrations. Lattice modes are observed at 172, 199 and 218 cm(-1). A broad low intensity band at 3095 cm(-1) is attributed to the hydrogen bonded OH units in the atelestite structure. A weak band at 1082 cm(-1) is assigned to δ(BiOH) vibration.
The NIR spectra of reichenbachite, scholzite and parascholzite have been studied at 298
K. The spectra of the minerals are different, in line with composition and crystal structural variations. ...Cation substitution effects are significant in their electronic spectra and three distinctly different electronic transition bands are observed in the near-infrared spectra at high wavenumbers in the 12,000–7600
cm
−1 spectral region. Reichenbachite electronic spectrum is characterised by Cu(II) transition bands at 9755 and 7520
cm
−1. A broad spectral feature observed for ferrous ion in the 12,000–9000
cm
−1 region both in scholzite and parascholzite. Some what similarities in the vibrational spectra of the three phosphate minerals are observed particularly in the OH stretching region. The observation of strong band at 5090
cm
−1 indicates strong hydrogen bonding in the structure of the dimorphs, scholzite and parascholzite. The three phosphates exhibit overlapping bands in the 4800–4000
cm
−1 region resulting from the combinations of vibrational modes of (PO
4)
3− units.
The application of near-infrared and infrared spectroscopy has been used for identification and distinction of basic Cu-sulphates that include devilline, chalcoalumite and caledonite. Near-infrared ...spectra of copper sulphate minerals confirm copper in divalent state. Jahn–Teller effect is more significant in chalcoalumite where
2B
1g
→
2B
2g transition band shows a larger splitting (490
cm
−1) confirming more distorted octahedral coordination of Cu
2+ ion. One symmetrical band at 5145
cm
−1 with shoulder band 5715
cm
−1 result from the absorbed molecular water in the copper complexes are the combinations of OH vibrations of H
2O. One sharp band at around 3400
cm
−1 in IR common to the three complexes is evidenced by Cu
OH vibrations. The strong absorptions observed at 1685 and 1620
cm
−1 for water bending modes in two species confirm strong hydrogen bonding in devilline and chalcoalumite. The multiple bands in
ν
3 and
ν
4(SO
4)
2− stretching regions are attributed to the reduction of symmetry to the sulphate ion from T
d to C
2V. Chalcoalumite, the excellent IR absorber over the range 3800–500
cm
−1 is treated as most efficient heat insulator among the Cu–sulphate complexes.
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