Different spectra

In this study, achira (Canna edulis) starch was oxidized by sodium hypochlorite and the effects of different concentration of oxidation agent (1, 2, 3 and 5%) on the physicochemical properties, morphological properties and crystallinity of achira starch (AS) was investigated. The carbonyl and carboxyl content, starch colour parameters, swelling capacity, solubility, IR spectra, SEM and XRD of native and oxidized achira starch (OAS) were evaluated.

7p dianmotminh02 03-05-2024 1 1   Download

In this paper, a thin stearic acid (SA) film was deposited onto the polyurethane (PU) coatings with different concentrations of stearic acid in the ethanol (1 wt.%, 2 wt.% and 3 wt.%) by centrifuged technique. Fourier transform infrared spectra (FTIR) and water contact angle (WCA) method were performed to characterize and evaluate the hydrophobic layer formed on the surface of the samples.

9p dianmotminh02 03-05-2024 3 2   Download

Ebook "Computer-based structure elucidation from spectral data: The art of solving problems" is composed of three parts. Part I contains a concise description of the ACD/Structure Elucidator flow diagram, its knowledgebase, and the fundamental concepts making up the theoretical basis of CASE (Chap. 1). Different strategies regarding the application of the system depending on the specific features of the problem being solved are discussed in Chap. 2.

458p tudohanhtau1006 29-03-2024 3 1   Download

Ebook "A structural and vibrational study of the chromyl chlorosulfate, fluorosulfate, and nitrate compounds" presents important studies related to the structural and vibrational properties on the chromyl compounds based on Ab-initio calculations. The synthesis and the study of such properties are of chemical importance because the stereo-chemistries and reactivities of these compounds are strongly dependent on the coordination modes that adopt the different ligands linked to the chromyl group.

90p coduathanh1122 27-03-2024 3 1   Download

Ebook "Infrared spectroscopy of minerals and related compounds" provides an overview of the application of IR spectroscopy in mineralogical investigations, as well as modern trends in the IR spectroscopy of minerals. It includes the most important methodological aspects; characteristic IR bands of different chemical groups and coordination polyhedra; application of IR spectroscopy to the investigation of the crystal chemistry of amphiboles, phyllosilicates, tourmalines etc.;...

1116p duongthandue0501 28-02-2024 2 1   Download

ZnO doped with different concentrations (2, 4, 6, 8 and 10%) of ceria was synthesized by the conventional solidestate reaction method. X-ray diffraction spectra confirm that all the samples have a hexagonal structure. The structural properties of the samples were studied from X-ray diffraction data.

7p viberbers 09-08-2023 5 3   Download

Polydentate, unsymmetrical, and multi metal ion sensing Schiff bases comprised of ferrocenecarboxaldehyde attached azomethine group at one side and aromatic aldehyde linked imine on the other side have been synthesized. Cumulative addition of different metal salts solution to receptors solution, changes the electronic spectra contrarily and for the addition of Cu2+ ions, generation of MLCT charge transfer band responsible for the coordination of metal ion with a receptor is observed.

21p lyhuyenthu 31-01-2023 3 2   Download

Infrared spectral analysis of milk is cheap, fast, and accurate. Infrared light interacts with chemical bonds present inside the milk, which means that Fourier transform infrared milk spectra are a reflection of the chemical composition of milk. Heritability of Fourier transform infrared milk spectra has been analysed previously.

14p vihagrid 30-01-2023 5 3   Download

Previous studies have observed mineral specific variations in the ratios of IRSL signals stimulated at the different discrete wavelengths of lines corresponding to Xe lamp emission lines, which fall within the broad excitation spectrum of IRSL. Meanwhile recent accounts of IRSL have referred to single trapping systems within the excitation band, and modelled excitation spectra as continuous gaussian distributions.

8p vironald 15-12-2022 19 4   Download

The potential confounding influence of heat on the electron spin resonance (ESR) spectra of fingernails has been studied in irradiated and unirradiated samples. The samples were heated at different temperatures between 20 and 160 ◦C for 1 h. The experimental temperature range was selected considering that the fingernails may be accidentally exposed to heat during normal daily activities or in a certain working environment.

11p vironald 15-12-2022 7 3   Download

The use of a highly divergent field distribution (i.e. corona discharge or micro discharge) is essential in order to analyse different breakdown stages. In our work, we have measured the emission spectra and specially, the pressure broadening and shift of atomic lines and molecular bands.

5p vijaguar 16-11-2022 12 1   Download

In the work "A Raman study of cation-disorder transition temperature of natural \(MgA{l_2}{O_4}\) spinel", the author have measured Raman spectra of samples of natural \(MgA{l_2}{O_4}\) spinel before and after annealing at different temperatures and quenching. The appearance of 727 cm 1 mode in the samples annealed at 800oC or higher is believed to be due to the cation-disorder of spinel.

4p runordie5 04-07-2022 3 2   Download

The paper "The photoluminescence enhancement of Mn2+ ions and the crystal field in ZnS:Mn nanoparticles covered by polyvinyl alcohol" report the synthesis of ZnS:Mn/PVA nanoparticles by second method, in which PVA solution is mixed from the beginning with the initial solutions used to synthesize ZnS:Mn nanoparticles. The microstructures, morphology of ZnS:Mn/PVA nanoparticles, the PL enhancement of Mn2? ions by different PVA mass, the absorption and radiation transitions in the ZnS:Mn crystals and the crystal field strength Dq are investigated and explained.

17p runordie3 27-06-2022 6 2   Download

Lifelong learning is fragmented and in different spectra according to users, organizations, lectures and so on. The desire to study is different from children to the elderly and any of them cannot be ignored. Accordingly, the characteristics of the organization and the purpose of a lecture are different by the desired users and this makes lifelong learning data impossible to be included in a standardized framework.

13p vimarissamayer 02-06-2022 13 1   Download

Fractal analysis helped find differences in species in the organisation of fish otolith crystalline surfaces in 2 closely related and 2 distant species. To determine regularities of this organisation, we used the microcanonical method of multifractal spectra. It was revealed that the differences of multifractal spectra were more significant for longer distances of taxonomic divergence.

7p dolomite36 30-12-2021 10 0   Download

In this study peripherally tetra-substituted metal-free, metallophthalocyanines bearing (3,4-dimethoxybenzyl) oxy groups have been synthesized and characterized. Electrochemical properties of novel phthalocyanines 4, 5, 6, and 7 were determined by cyclic and square wave voltammetry in order to define their possible applications in different electrochemical technologies. CoII and TiIVO metal ions behave as redox active cations in the core of the CoPc and TiOPc complexes, respectively

12p langthannam 29-12-2021 5 0   Download

The photophysical properties of new sulfonamides synthesized recently were investigated in different solvents. Shifts in the absorption and fluorescence spectra of both compounds (S10 and S11) occurred depending on the solvents used. Ground and excited state dipole moments of the molecules were calculated using the spectral shifts of the compounds in different solvents and polarity function of solvents, respectively. They were 1.32 and 1.46 D for S10 and 1.71 and 4.89 D for S11.

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In this report, Raman spectra of the Zn1−xMnxO samples annealed at various temperatures in different ambients, such as in air, in argon and in oxygen were studied. The results indicate that the Raman spectra of the samples are affected significantly by the annealing temperature and by the ambient. The most intensive peak in the Raman spectra at approximately 570 cm−1 has two components, one at around 570 cm−1 (A1(LO)) and the other at 580 cm−1 (E1(LO)). In contrast to previous results, with increasing annealing temperature, the intensity of 570 cm−1 peak still remains anomalously high.

7p thienlangso 15-12-2021 12 0   Download

Photophysical properties of lamotrigine (LMT) were investigated at different pH values. Lamotrigine exhibited a broad absorption band at 308 nm that was shifted to 268 nm at pH 2.0 due to protonation (HLMT+). Emission spectra of LMT at different pH values showed a single band at 483 nm except for at pH 2.0, where a second band at 502 nm was observed due to the deprotonation from the singlet excited state. LMT pH profile was used to calculate pK a of LMT in excited and ground states (pK a* = 4.50 and pK a = 5.90).

10p tudichquannguyet 29-11-2021 20 0   Download

Eight novel 3-(4-(benzyloxy)phenyl)-5-(4-bromophenyl)-1-(4-substituted-phenyl)formazan (4a–4h) were synthesized by coupling of substituted phenylhydrazones with diazonium salts of 4-bromoaniline. The substituted phenylhydrazones, which are intermediate products, were obtained from the condensation of substituted phenylhydrazines with 4-(benzyloxy)benzaldehyde. All target compounds were characterized by using FTIR, 1 H NMR, 13 C NMR, LC−MS spectrometry, and elemental analysis. Absorption spectra of these compounds in solvents with different polarities were investigated thoroughly.

31p tudichquannguyet 29-11-2021 8 1   Download