scholarly journals X-RAY STRUCTURAL ANALYSIS OF COTTONS AND HERBACEOUS CELLULOSE

2021 ◽  
pp. 61-71
Author(s):  
Kseniya Sergeyevna Momziakova ◽  
Aleksey Aleksandrovich Shinkarev ◽  
Timur Rustamovich Deberdeev ◽  
Zimfira Talgatovna Valishina ◽  
Aleksandr Aleksandrovich Berlin ◽  
...  
Keyword(s):  
Transverse Direction ◽  
Raw Materials ◽  
Correlation Coefficients ◽  
Coherent Scattering ◽  
High Viscosity ◽  
Degree Of Polymerization ◽  
Degree Of Crystallinity ◽  
Hammer Mill ◽  
Mechanical Destruction ◽  
X Ray

It was found that the extrusion treatment of cotton cellulose in an aqueous medium, followed by drying and grinding on a hammer mill leads to a decrease in the crystallite size in the transverse direction ([110] and [100]) as a result of mechanical destruction of cellulose macromolecules, and the subsequent acid hydrolysis of cellulose in H2SO4 solutions to an increase in the size of crystallites in the transverse direction ([110], [110] and [100]) due to co-crystallization processes. It is shown that alkaline cooking of cellulose-containing material, followed by extrusion processing, washing, drying and grinding on a hammer mill leads to an increase in the transverse dimensions of crystallites in the [110] and [100] directions for flax cellulose and in the [110], [110] and [100] – for cellulose from oats and alfalfa as a result of partial removal of lignin and hemicelluloses from the cellulose-containing material. Differences were revealed in the sizes of the coherent scattering regions and the parameters of the crystallographic cell of cellulose samples from cotton and herbaceous plants (flax, oats, and alfalfa), as well as between samples from oats and alfalfa obtained under the same conditions with the same type of feedstock (straw). It has been established that the proposed stepwise technology for processing cotton and linen fibers leads to a slight decrease in the degree of crystallinity and the average degree of polymerization, which indicates that the developed technology for obtaining high-viscosity powder celluloses for various purposes is promising. Correlation coefficients are established between the values of the degree of ordering of the structure of cellulose samples from various plant raw materials, calculated using X-ray diffraction analysis and FT-IR spectroscopy, which make it possible to adequately compare all the known literature and experimental data.

scholarly journals PREPARATION OF NANOCELLULOSE FROM NON-WOOD PLANT RAW MATERIALS

2019 ◽  
pp. 15-21
Author(s):  
Kseniya Sergeyevna Momziakova ◽  
Timur Rustamovich Deberdeev ◽  
Maksim Sergeyevich Vershinin ◽  
Vladimir Viktorovich Leksin ◽  
Aleksandr Aleksandrovich Momziakov ◽  
...  
Keyword(s):  
Structural Modification ◽  
Raw Materials ◽  
Crystallinity Index ◽  
Subsequent Treatment ◽  
Degree Of Polymerization ◽  
Degree Of Crystallinity ◽  
X Ray ◽  
Plant Raw Materials ◽  
Transmission Electron ◽  
Effective Use

The purpose of this work was to study the possibility of obtaining nanocellulose (NC) by ultrasonic (US) processing in the medium of liquid nitrogen (LN) powdered cellulose. To achieve this goal, it was necessary to determine the effect of the time of ultrasonic treatment in the medium of LN on the dispersed composition, crystallinity index and degree of polymerization (DP) of cellulose samples. Studies were performed using a powder X-ray diffractometer, a laser particle analyzer, and a scanning and transmission electron microscope. DP of cellulose was determined by the viscosity of its solution in cadoxene by the standard method. It has been found that cryogenic grinding of flax cellulose samples does not lead to significant changes in its structural modification and degree of crystallinity, which indicates the high resistance of this material to such effects. However, ultrasonic exposure in the medium of LN with the subsequent treatment with 25%, 45%, 65% H2SO4 allows to obtain cellulose nanospheres with a diameter of 48 to 437 nm and a yield of up to 40%. Unlike other types of nanoparticles (nanofibrillary, nanocrystalline cellulose), cellulose nanospheres have a larger surface area, which opens up the possibility of their effective use for the modification of composite materials.

Effect of Partial Substitution of Sr by Ba on the Structural Properties of Tl0.8Ni0.2Sr2-xBrxCa2Cu3O9-δ System

2021 ◽  
Vol 900 ◽  
pp. 172-179
Author(s):  
Mohammed Abdul Nebi Thejeel ◽  
Rihab Nassr Fadhil ◽  
Shatha H. Mahdie ◽  
Kareem Ali Jasim ◽  
Auday H. Shaban
Keyword(s):  
Structural Properties ◽  
Crystal Size ◽  
Full Width Half Maximum ◽  
Raw Materials ◽  
Degree Of Crystallinity ◽  
Partial Substitution ◽  
X Ray Diffraction ◽  
Solid State Reaction Technique ◽  
X Ray ◽  
Barium Concentration

In this manuscript, the effect of substituting strontium with barium on the structural properties of Tl0.8Ni0.2Sr2-xBrxCa2Cu3O9-δ compound with x= 0, 0.2, 0.4, have been studied. Samples were prepared using solid state reaction technique, suitable oxides alternatives of Pb2O3, CaO, BaO and CuO with 99.99% purity as raw materials and then mixed. They were prepared in the form of discs with a diameter of 1.5 cm and a thickness of (0.2-0.3) cm under pressures 7 tons / cm2, and the samples were sintered at a constant temperature of 860 ° C. The structural properties were studied using X-ray diffraction for all samples, and the results showed that the samples have tetragonal structure and the change of the parameters structure with the change of the barium concentration. Full Width Half Maximum (FWHM) was calculated by Orange Pro using X-RAY data. The crystal size was calculated using Scherrer and Willeamson-Heall methods, where the results showed that the crystal size, compliance and degree of crystallinity changed with the change of barium concentration, and the highest average for the crystal size was 70.0271nm at x=0, and crystallization at 61.46% at x=0.6, and the strain decreased to 0.0037 when barium concentration equals 0.4.

scholarly journals ANALYSIS OF STRUCTURAL CHANGES OF CELLULOSE COMPONENT IN PROCESS OF ELEMENTARIZATION OF FLAX FIBERS

2017 ◽  
Vol 60 (6) ◽  
pp. 102 ◽  
Author(s):  
Alexandr E. Zavadskii ◽  
Valeria G. Stokozenko ◽  
Andrey P. Moryganov ◽  
Igor Yu. Larin
Keyword(s):  
Supramolecular Structure ◽  
Structural Changes ◽  
Raw Materials ◽  
Diffraction Method ◽  
Degree Of Crystallinity ◽  
X Ray ◽  
Flax Fibers ◽  
Cellulose Iβ ◽  
Deep Purification ◽  
Cellulose Component

The comparative research of composition and supramolecular structure of the flax fibers received by methods of a cottonization and a mechanical elementarization under the influence of the cyclic deforming loadings was conducted. It was shown that under the influence of cyclic loadings removal of a considerable part of impurity with the increase in content of cellulose to 80.1% is reached. At the same time, division of complexes onto elementary filament provides the increase in the total surface of material and, as a result, to availability of fibers to the reagents at the subsequent alkaline boiling. X-ray analysis of flax samples with a method of comparison of the normalized parameters of diffraction by crystalline regions of cellulose allowed to establish that degree of crystallinity of a cellulose component of fibers remains constant even at deep purification of raw materials under the influence of cyclic deformations and subsequent boiling. The research of the oriented fibers by X-ray diffraction method has shown that removal of impurity from flax in the course of an elementarization has only weak influence on the sizes of crystallites of cellulose. The increase in the cross sizes of crystallites by 4 – 6% was observed at deep purification of fibers due to the boiling. This phenomenon can be connected with the decrease in influence of a diffraction maximum from impurity on half-width of the equatorial reflex 200 for cellulose Iβ. It should be noted that the longitudinal sizes of crystallites at the same time do not change. It was suggested on possible influence of decrease in content of impurity on supramolecular structure of an amorphous phase of cellulose and as a result on the observed growth of sorption and mechanical properties of flax fibers at an elementarization by method of cyclic deformation.Forcitation:Zavadskii A.E., Stokozenko V.G., Moryganov A.P., Larin I.Yu. Analysis of structural changes of cellulose component in process of elementarization of flax fibers. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 6. P. 102-108.

Usability of field X-ray fluorescence analyzers for determination of the chemistry of cement raw materials - using an example of Mokrá Quarry

2016 ◽  
Author(s):  
Jiří Zimák ◽  
Kristýna Dalajková ◽  
Roman Donocik ◽  
Petr Krist ◽  
Daniel Reif ◽  
...  
Keyword(s):  
Raw Materials ◽  
X Ray

scholarly journals Characterization of a back-illuminated CMOS camera for soft x-ray coherent scattering

2019 ◽  
Author(s):  
Kewin Desjardins ◽  
Horia Popescu ◽  
Pascal Mercère ◽  
Claude Menneglier ◽  
Roland Gaudemer ◽  
...  
Keyword(s):  
Coherent Scattering ◽  
Cmos Camera ◽  
X Ray ◽  
Back Illuminated

scholarly journals Waste and Solar Energy: An Eco-Friendly Way for Glass Melting

2021 ◽  
Vol 5 (2) ◽  
pp. 16
Author(s):  
Isabel Padilla ◽  
Maximina Romero ◽  
José I. Robla ◽  
Aurora López-Delgado
Keyword(s):  
Solar Energy ◽  
Environmental Sustainability ◽  
Raw Materials ◽  
Glass Melting ◽  
Glass Network ◽  
X Ray Diffraction ◽  
X Ray ◽  
Concentrated Solar Energy ◽  
Calcium Source ◽  
The Aluminum Industry

In this work, concentrated solar energy (CSE) was applied to an energy-intensive process such as the vitrification of waste with the aim of manufacturing glasses. Different types of waste were used as raw materials: a hazardous waste from the aluminum industry as aluminum source; two residues from the food industry (eggshell and mussel shell) and dolomite ore as calcium source; quartz sand was also employed as glass network former. The use of CSE allowed obtaining glasses in the SiO2-Al2O3-CaO system at exposure time as short as 15 min. The raw materials, their mixtures, and the resulting glasses were characterized by means of X-ray fluorescence, X-ray diffraction, and differential thermal analysis. The feasibility of combining a renewable energy, as solar energy and different waste for the manufacture of glasses, would highly contribute to circular economy and environmental sustainability.

scholarly journals Brewers’ spent grain as substrate for dextran biosynthesis by Leuconostoc pseudomesenteroides DSM20193 and Weissella confusa A16

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Prabin Koirala ◽  
Ndegwa Henry Maina ◽  
Hanna Nihtilä ◽  
Kati Katina ◽  
Rossana Coda
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Raw Materials ◽  
Degree Of Polymerization ◽  
Raw Material ◽  
Fermentation Time ◽  
Viscosity Increase ◽  
Spent Grain ◽  
Leuconostoc Pseudomesenteroides ◽  
Weissella Confusa

Abstract Background Lactic acid bacteria can synthesize dextran and oligosaccharides with different functionality, depending on the strain and fermentation conditions. As natural structure-forming agent, dextran has proven useful as food additive, improving the properties of several raw materials with poor technological quality, such as cereal by-products, fiber-and protein-rich matrices, enabling their use in food applications. In this study, we assessed dextran biosynthesis in situ during fermentation of brewers´ spent grain (BSG), the main by-product of beer brewing industry, with Leuconostoc pseudomesenteroides DSM20193 and Weissella confusa A16. The starters performance and the primary metabolites formed during 24 h of fermentation with and without 4% sucrose (w/w) were followed. Results The starters showed similar growth and acidification kinetics, but different sugar utilization, especially in presence of sucrose. Viscosity increase in fermented BSG containing sucrose occurred first after 10 h, and it kept increasing until 24 h concomitantly with dextran formation. Dextran content after 24 h was approximately 1% on the total weight of the BSG. Oligosaccharides with different degree of polymerization were formed together with dextran from 10 to 24 h. Three dextransucrase genes were identified in L. pseudomesenteroides DSM20193, one of which was significantly upregulated and remained active throughout the fermentation time. One dextransucrase gene was identified in W. confusa A16 also showing a typical induction profile, with highest upregulation at 10 h. Conclusions Selected lactic acid bacteria starters produced significant amount of dextran in brewers’ spent grain while forming oligosaccharides with different degree of polymerization. Putative dextransucrase genes identified in the starters showed a typical induction profile. Formation of dextran and oligosaccharides in BSG during lactic acid bacteria fermentation can be tailored to achieve specific technological properties of this raw material, contributing to its reintegration into the food chain.

scholarly journals Polyurethane Composite Foams Synthesized Using Bio-Polyols and Cellulose Filler

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3474
Author(s):  
Katarzyna Uram ◽  
Milena Leszczyńska ◽  
Aleksander Prociak ◽  
Anna Czajka ◽  
Michał Gloc ◽  
...  
Keyword(s):  
Cross Sections ◽  
Raw Materials ◽  
Polyurethane Foams ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Polyurethane Composite ◽  
Composite Foams ◽  
Closed Cell ◽  
Ft Ir ◽  
The Fourier Transform

Rigid polyurethane foams were obtained using two types of renewable raw materials: bio-polyols and a cellulose filler (ARBOCEL® P 4000 X, JRS Rettenmaier, Rosenberg, Germany). A polyurethane system containing 40 wt.% of rapeseed oil-based polyols was modified with the cellulose filler in amounts of 1, 2, and 3 php (per hundred polyols). The cellulose was incorporated into the polyol premix as filler dispersion in a petrochemical polyol made using calenders. The cellulose filler was examined in terms of the degree of crystallinity using the powder X-ray diffraction PXRD -and the presence of bonds by means of the fourier transform infrared spectroscopy FT-IR. It was found that the addition of the cellulose filler increased the number of cells in the foams in both cross-sections—parallel and perpendicular to the direction of the foam growth—while reducing the sizes of those cells. Additionally, the foams had closed cell contents of more than 90% and initial thermal conductivity coefficients of 24.8 mW/m∙K. The insulation materials were dimensionally stable, especially at temperatures close to 0 °C, which qualifies them for use as insulation at low temperatures.

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