Search results for "Solid-State"
showing 10 items of 530 documents
Raman spectral identification of phase distribution in anodic titanium dioxide coating
2017
Growing need for cleaner environment and energy production has brought about a hunt for perspective materials. One of such perspective materials is titanium dioxide (TiO2, titania) due to its chemical stability and photocatalytic properties. Titania can be synthesized through many methods but anodization process is one of the prevailing methods to produce high active surface nanostructured titania. Various anodization electrolytes produce different polymorphs of TiO2. Uniform phase distribution on the surface is crucial for higher photocatalytic activity. In this research, the influence of two electrolytes on polymorph phase distribution of TiO2 was investigated. Phase distribution correlat…
Kinetics of solid-state fermentation of lupin with Rhizophus oligosporus based on nitrogen compounds balance
2021
Solid-state fermentation could be a potentially effective method for improving the nutritional value of legumes. The objective of this study was to explore this technology in Lupinus mutabilis, a species of lupin, using a strain of Rhizopus oligosporus mold for solid-state fermentation. Three L. mutabilis varieties (INIAP-450, INIAP-451, and Criollo) were evaluated, including the effect of the grain status (whole or ground) and integument or husk (presence or absence). Kinetic parameters of the fermentation process were studied to define the specific speed of nitrogen formation and the digestibility and nutritional quality of the resulting protein. After incubation at 28 °C for 96 h, the ti…
Grape pulp, grape pips and their mixture: Novel substrates or supports for solid state fermentation
1997
Grape marc, comprising of grape pulp and grape pips, is generated in high quantities during ethanol production, but has no significant commercial value. The components of the grape marc, individually or in combination, can serve as substrate or support in solid state fermentation. The potential benefits of sieved fractions (800-3150 µm particle size) was, therefore, evaluated using Trichoderma viride, with or whithout enrichment. Based on sorption isotherm profiles, grape pulp showed the best performance, though its ability to promote biomass formation was the lowest. The latter could be improved by enrichment with glucose. It, thus, offers potential as a reusable support. Grape pips promot…
The effect of Pediococcus acidilactici and Lactobacillus sakei on biogenic amines formation and free amino acid profile in different lupin during fer…
2016
Abstract The effect of Pediococcus acidilactici and Lactobacillus sakei strains on biogenic amines (BAs) formation during submerged and solid state fermentation of Lupinus luteus and Lupinus angustifolius was analysed. The composition of lupin seeds was evaluated and the influence of fermentation on free amino acid (FAA) profile was investigated. The highest protein and carbohydrate contents were found in L. luteus var. ‘Vilciai’, the highest carbohydrate contents – in L. angustifolius hybrid lines No. 1701 and No. 1800, and fat – in L. angustifolius hybrid lines No. 1700, No. 1703 and No. 1734. The interaction between the fermentation method, the bacterial strains used and lupin varieties …
Quantum wells within quantum dots, a CdS/HgS nanoheterostructure with global and local confinement
1998
Semiconductor nanocrystals prepared by methods of wet chemistry are similar to MBE grown quantum dots where the mobility of the charge carriers is reduced to zero dimensionality. In this paper we summarize the physics of a unique system in which the charge carriers are locally confined within a heterogeneous quantum dot. With high resolution electron microscopy we will show that epitaxial growth ot atomic layer precision is possible by methods of solution chemistry leading to CdS quantum dots with embedded HgS quantum wells (QDQWs). The photophysics of this system is investigated by time-correlated single photon counting, transient differential absorption and fluorescence line narrowing spe…
Hyper-reticulated calixarene polymers: a new example of entirely synthetic nanosponge materials
2018
New calixarene-based nanosponges (CaNSs), i.e., hyper-reticulated polymers constituted by calixarene monomer units joined by means of bis(1,2,3-trialzolyl)alkyl linkers, were synthesized, characterized and subjected to preliminary tests to assess their supramolecular absorption abilities towards a set of suitable organic guests, selected as pollutant models. The synthesis was accomplished by means of a CuAAC reaction between a tetrakis(propargyloxy)calix[4]arene and an alkyl diazide. The formation of the polymeric network was assessed by means of FTIR and 13C{1H} CP-MAS solid-state NMR techniques, whereas morphological characterization was provided by SEM microghaphy. The materials were pro…
Supramolecular complexes formed by dimethoxypillar[5]arenes and imidazolium salts: A joint experimental and computational investigation
2017
To gain more insights into the factors acting on the stability of complexes formed by pillar[5]arenes, we investigated the interaction of dimethoxypillar[5]arene with some 1-(n-alkyl)-3-(9-anthracenylmethyl)-imidazolium based organic salts. In particular, we used salts differing in not only the anion nature ([Cl−], [BF4−], [NTf2−] and [SbF6−]) and alkyl chain length (butyl, octyl and dodecylimidazolium derivatives), but also the presence of a hydrogenated or fluorinated tail (octyl and perfluorooctylimidazolium derivatives). Host–guest systems were analysed in solution, solid state and gas phase, using a combined approach of different techniques like fluorescence, 1H NMR, ESI-MS, DSC and DF…
Highly Functionalized Brønsted Acidic/Lewis Basic Hybrid Ferrocene Ligands: Synthesis and Coordination Chemistry
2019
International audience; A general challenging issue in the synthesis of hemilabile ferrocene ligands is the access to highly functionalized ferrocene starting materials. These can bear donor/acceptor atoms, additional functional and structuring spectator substituents, but the preparation of such species poses general synthetic difficulties. We report herein alternative synthetic routes to hybrid ferrocene donors such as tert-butylated phosphanylcarboxylic acids and their corresponding aldehydes. These hybrid ambiphilic species that combine Brønsted-acidic and Lewis-basic functional moieties in their structure were characterized by multinuclear NMR and single-crystal X-ray diffraction analys…
A New Synthetic Method and Solution Equilibria for the Chlorotitanate( IV ) Anions − Evidence for the Existence of a New Species: [Ti 2 Cl 11 ] 3−
2004
TiCl3 is oxidized by SOCl2 in the presence of the appropriate amount of [NEt3Bz]Cl or [PPN]Cl [Bz = benzyl; PPN = bis(triphenylphosphanyl)iminium] to afford the corresponding salts of [Ti2Cl9]−, [Ti2Cl10]2− or [TiCl6]2−. The results of cyclic voltammetric and solution IR studies in the Ti−Cl stretching region are interpreted in terms of a rapid chloride-redistribution equilibrium between [Ti2Cl10]2− on one side and a mixture of [Ti2Cl9]− and a previously unreported [Ti2Cl11]3− species on the other side. In the solid state, however, a compound with the [PPN]3[Ti2Cl11] stoichiometry exists as a mixture of [PPN]2[Ti2Cl10] and [PPN]2[TiCl6]. The PPN salt of [Ti2Cl9]− has been structurally chara…
Cysteamine and its homoleptic complexes with group 12 metal ions. Differences in the coordination chemistry of ZnII, CdII, and HgII with a small N,S-…
2005
2-Ammoniumethanethiolate, (-)SCH(2)CH(2)NH(3)(+), the first structurally characterized zwitterionic ammoniumthiolate, is the stable form of cysteamine (HL) in the solid state and in aqueous solution. Reactions of ZnCl(2), Cd(Oac)(2), and HgCl(2) with cysteamine and NaOH in a 1:2:2 ratio, respectively, lead to the homoleptic complexes ML(2). Their single-crystal X-ray structures demonstrate basic differences in the coordination chemistry of Zn(II), Cd(II), and Hg(II). While chelating N,S-coordination modes are found for all metal ions, Zn(II) forms a mononuclear complex with a distorted tetrahedral Zn(N(2)S(2)) coordination mode, whereas Hg(II) displays a dimer with Hg(N(2)S(2)) coordinated …