scholarly journals Study of Cotton Fiber Surface After Thermal Processing in the Vacuum Chamber by the Method of Scanning Electron Microscopy

2020 ◽  
Vol 6 (8) ◽  
pp. 34-38
Author(s):  
N. Zhogashtiev ◽  
Y. Tashpolotov ◽  
N. Kalmurzaev

The article presents the results of a study of the surface of cotton fibers before and after thermal processing in a vacuum chamber by scanning electron microscopy. It has been established that various factors affect the structural and physicochemical properties of an ultrathin composite material based on ultra-dispersed carbon fiber. In this work, the microstructures of an ultrathin composite material obtained based on ultrafine cotton fibers were investigated and a chemical analysis of these fibers was carried out. Based on chemical analysis, it was found that the content of heat-treated cotton fiber is 98.62% during heat treatment (from 1000 to 1200 °C). Along with this, the resulting powder had carbon fibers with sizes from 2.42 to 9.18 μm, and thus ultra-thin fibers have high chemical activity. It is shown that heat treatment of the fiber leads to molecular bonding of the outer layer of the cotton fiber.

Clay Minerals ◽  
2014 ◽  
Vol 49 (1) ◽  
pp. 75-89 ◽  
Author(s):  
D. Papoulis ◽  
S. Komarneni ◽  
D. Panagiotaras

AbstractTrachyandesite rocks, occurring over an area of about 1 km2in the southwest part of Limnos Island, Greece, are altered mainly to halloysite. The samples were collected and analysed by polarizing microscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and chemical analysis. The alteration of plagioclase to halloysite follows seven discrete stages that are described in detail. The geochemical evaluation of the data shows enrichment of the lightREE(LREE) over heavyREE(HREE) as expressed by the (La/Yb)n ratio. TheΣLREErange from 206.44 to 272.30, while the sum ofHREEvaries from 11.01 to 26.26. The (La/Yb)n ratio ranges from 9.72 to 27.64. Fractionation amongLREEexpressed as (La/Sm)n and between middleREE(MREE) andHREEis shown as (Tb/Yb)n ratios. The most altered rocks close to the fault zone have high (Tb/Yb)n ratios and low (La/Sm)n and Eu/Eu* ratios. Although mineralogy and clay mineral textures indicate hydrothermal genesis of halloysite, the geochemical data are not conclusive due to a secondary weathering effect.


2020 ◽  
Vol 94 ◽  
Author(s):  
O.M. Amin ◽  
M. Sharifdini ◽  
R.A. Heckmann ◽  
M. Zarean

We describe morphological features not previously reported for this old acanthocephalan Nephridiacanthus major (Bremser, 1811 in Westrumb, 1821) Golvan, 1962 first described over 200 years ago. Our specimens were collected from long-eared hedgehog Hemiechinus auritus (Gmelin, 1770) (Erinaceidae) in Iran. We compare the morphometrics of our material with others previously reported from the same host in Iran, Russia, central Asia and Europe. Our specimens had markedly smaller proboscides, proboscis hooks and lemnisci than those reported from Russia and central Asia, but comparable measurements of other structures with specimens previously described from other collections. We document our new observations with scanning electron microscopy features not previously demonstrable by other observers and provide a chemical analysis of proboscis hooks using energy-dispersive X-ray analysis for the first time. The molecular profile of this acanthocephalan, based on 18S rDNA and cox1 genes, was generated for the first time. The phylogenetic analysis showed that N. major is placed in a clade of the family Oligacanthorhynchidae, well separated from the families Moniliformidae and Gigantorhynchidae.


Cerâmica ◽  
2020 ◽  
Vol 66 (380) ◽  
pp. 483-495
Author(s):  
V. M. J. Salgado-Campos ◽  
L. C. Bertolino ◽  
F. J. da Silva ◽  
J. C. Mendes

Abstract This study reports the mineralogical characterization of kaolin occurrences in the State of Rio de Janeiro, Brazil, to identify new kaolinite and halloysite deposits. Samples were collected in 10 pegmatites with varying sizes for X-ray diffractometry, chemical analysis by X-ray fluorescence, and scanning electron microscopy studies. The results indicated that the kaolin occurrences were of weathered origin, wherein some places there were occurrences of tubular halloysite. Concerning the regolith stratigraphy, samples located in the saprock zone were found to contain kaolinite and/or halloysite contents from 0 to 10.1%, while those located in the saprolite zone contained kaolinite and/or halloysite contents from 16.3% to 34.9%. Kaolinite and/or halloysite-7Å were formed from plagioclase weathering instead of K-feldspar or mica, and the halloysite-7Å occurrence was related to samples in regions with a higher degree of weathering.


1997 ◽  
Vol 3 (4) ◽  
pp. 381-396
Author(s):  
S. Chandra ◽  
D. Van Gemert

Abstract Interior plaster from the Abbot's Palace of the Abbey of Villers-la-Ville, Brabant Wallon province, Belgium has been investigated. It is done by using chemical analysis, x-ray diffraction analysis, scanning electron microscopy, energy dispersive electron spectroscopy, and transmission electron microscopy. It is found that the rendering was made with lime rich mortar and animal hairs. The sand used was very fine and the hairs were very short. The solid constituents and the hairs were uniformly dispersed, which could have been obtained by the addition of some other natural polymer, containing protein.


Minerals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1122
Author(s):  
Zdeněk Klika ◽  
Marta Valášková ◽  
Lucie Bartoňová ◽  
Petra Maierová

An innovative chemical quantitative mineral analysis (CQMA) was successfully tested on a cordierite-based clay ceramic sample to quantify crystalline and amorphous components. The accuracy of this method was demonstrated on an added module to the CQMA program that used oxide formulas of amorphous phases obtained by energy dispersive X-ray spectroscopy (EDS) microprobe chemical analysis. This CQMA method was tested for three variants calculated using chemical analysis, i.e., X-ray diffraction (XRD) identification of crystalline (cordierite and enstatite) and amorphous phases by scanning electron microscopy (SEM)/EDS texture and microanalyses. The test results from CQMA suggest their application possibilities as well as the limits of their utilization.


2013 ◽  
Vol 750-752 ◽  
pp. 336-339
Author(s):  
Fa Chao Wu ◽  
Teng Fei Shen

In this work, CaCO3 nanoparticles have been synthesized via heat-treatment of a new precursor. Effect of calcinations temperature on particle size has been investigated. The products were characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). nanoCaCO3 was modified using chloroform as solvent and fatty acid as modifier atroom temperature. The advantage of this modification is that it can be proceed at room temperature and it can reduce energy consumption.


2014 ◽  
Vol 782 ◽  
pp. 537-540
Author(s):  
Peter Keša ◽  
Igor Hrmo ◽  
Pavel Diko ◽  
Marián Antalík

A composite material of graphite/polystyrene sulfonate was prepared by solvothermal method. The dissolution of polystyrene sulfonate in water ensures homogeneous distributions of graphite and creates composition material at room temperatures. Water removing by the drying, permit to prepare films. Structure of the film was analyzed by scanning electron microscopy. The influence of different ratio between graphite and polystyrene sulfonate is discussed.


Sign in / Sign up

Export Citation Format

Share Document