Identifying and quantifying amorphous and crystalline content in complex powdered samples: application to archaeological carbon blacks

2016 ◽  
Vol 49 (2) ◽  
pp. 585-593 ◽  
Author(s):  
Sophie Cersoy ◽  
Pauline Martinetto ◽  
Pierre Bordet ◽  
Jean Louis Hodeau ◽  
Elsa Van Elslande ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Organic Matter ◽  
Carbon Black ◽  
Methodological Approach ◽  
Mixed Phase ◽  
Carbon Blacks ◽  
Heterogeneous Samples ◽  
Scanning Electron ◽  
Black Materials

Carbon black materials have been frequently used from prehistory as pigments for drawings and paintings and also as dyes, inks and cosmetics, since they are easy to make by burning organic matter. However, the carbonaceous phases they form are often ill-ordered and not easy to characterize. Five carbon black Roman micro samples found in vessels in houses in Pompeii were studied. These precious powders correspond to mixed phase samples that contain both crystalline and ill-ordered components. Here, a methodological approach that accomplishes the identification, quantification and mapping of the different phases in these heterogeneous samples using synchrotron-based techniques is proposed. The results were compared with those from scanning electron microscopy. Information about the nature of the mixtures and the origin of carbon black pigments is obtained. The use of charred vegetable materials is concluded, independently of the shape and the nature of the container.

Characterization of Dispersions

1991 ◽  
Vol 64 (3) ◽  
pp. 386-449 ◽  
Author(s):  
W. M. Hess
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Carbon Black ◽  
Phase Distribution ◽  
Automated Image Analysis ◽  
Carbon Blacks ◽  
Transmission Electron ◽  
Vehicle Systems ◽  
Scanning Electron

Abstract The methods of pigment dispersion analysis have been reviewed in regard to their application to rubber, plastics, and other vehicle systems. The characteristics of dispersions have been divided into three categories: (1) agglomeration (2) microdispersion (networking) and (3) polymer-phase distribution. Stylus roughness measurements on cut surfaces offer the combination of simplicity and speed of operation with high accuracy and precision for measuring pigment agglomeration in elastomer systems of known composition. This method may also be applied to the surface of thin plastic extrudates. However, optical analyses of thin cryosections are preferred for most plastics or unknown rubber compounds containing high loadings of carbon black. X-radiography is generally preferable for the analysis of inorganic agglomeration in most polymeric vehicle systems. The scanning electron microscope is also applicable for this type of analysis and has the added capability of identifying unknown agglomerates by energy dispersive x-ray analysis. Automated image-analysis techniques may also be utilized in conjunction with microscopical methods for quantifying the agglomeration of most types of pigments. For carbon blacks, the most suitable materials for on-line image analyses with transmitted light are plastics, paints, and inks which contain low black loadings. Higher carbon-black loadings in rubber can be analyzed by incident light using metallographic polishing of sulfur-hardened specimens. The microdispersion of carbon blacks at the primary aggregate level can be measured by means of electrical conductivity. This method is not applicable to inorganic pigments, large-particle-size carbon blacks, or blacks at very high or low loadings. Pigment microdispersion in different vehicle systems may also be assessed by means of scanning electron microscopy of thick cross sections (plasma etched to enhance contrast) or by transmission electron microscopy of thin cryosections. The tendency for the finer pigments to form 3-dimensional network structures in elastomers may also be measured as a function of the augmentation of dynamic modulus from high to low strain amplitudes. Pigment phase distribution in elastomer blends may be studied by scanning electron microscopy or transmission electron microscopy of thin cryosections, in conjunction with a staining or etching procedure to produce contrast between the separate polymer components. Selective staining is applicable to blends of polymers which differ significantly in their relative levels of unsaturation (e.g., NR/CIIR). Pyrolytic etching (under vacuum) may be used to produce interzone contrast in blends of polymers which differ significantly in their resistance to thermal degradation (e.g., NR/BR, NR/SBR). Pyrolysis GC may be utilized to determine the amount of carbon black in the separate phases of certain elastomer blends. This method is based on the relative intensity of the primary GC peaks for the individual polymers. The chromatographs are obtained from the bound rubber (carbon-polymer gel) that is developed during the mixing of the compound.

Uranium-bearing stratiform organic matter in paleoplacers of the lower Huronian Supergroup, Elliot Lake – Blind River region, Canada

1985 ◽  
Vol 22 (12) ◽  
pp. 1930-1944 ◽  
Author(s):  
Tylon O. Willingham ◽  
Bartholomew Nagy ◽  
Lois Anne Nagy ◽  
David H. Krinsley ◽  
David J. Mossman
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Organic Matter ◽  
Local Development ◽  
Analytical Data ◽  
High Vacuum ◽  
Gas Chromatography Mass Spectrometry ◽  
River Region ◽  
Backscattered Scanning Electron Microscopy ◽  
Scanning Electron

The Elliot Lake – Blind River, Ontario, paleoplacer deposits in the basal Matineda Formation, lowermost member of the 2.25–2.45 Ga old Huronian Supergroup, contain organic matter chemically consistent with kerogen. This substance is also referred to as thucholite. Uranium ores and some gold occur here, and these minerals may be in close association with the kerogen. Two uraniferous and auriferous stratiform kerogens, obtained from the Denison Mines Limited's Denison mine and Rio Algom Limited's Stanleigh mine, have been analyzed by combined high-vacuum pyrolysis – gas chromatography – mass spectrometry and by neutron activation. The reflectances of these samples have also been determined. Related samples containing dispersed kerogen have been examined by backscattered scanning electron microscopy. The polymer-like matrix of the two stratiform kerogens consists of aromatic, alkyl aromatic hydrocarbon, and sulphur moieties and contains 20 and 32% uranium with gold abundances in the parts per billion range. The reflectances of the two stratiform kerogens are generally higher than those of the dispersed kerogens; the atomic H/C ratios of the former are −0.6 and −0.4. Backscattered scanning electron microscopy and petrographic observations reveal a complex diagenetic history. Stratigraphic position and supportive analytical data suggest that the stratiform kerogens were probably derived from ancient mats of cyanobacteria, subjected to various radiation-induced reactions, and, at least in part, were affected in a manner similar to the surrounding rocks. The latter experienced physical and chemical diagenetic reactions, which often caused repeated mineral fracturing and led to the local development of authigenic carbonates and feldspar. Some of the chemical nature and history of the stratiform kerogens resemble those of the Witwatersrand carbon seam kerogens.

scholarly journals Advanced Characterization of Organic Matter Decaying during Composting of Industrial Waste Using Spectral Methods

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1364
Author(s):  
Saloua Biyada ◽  
Mohammed Merzouki ◽  
Hamada Imtara ◽  
Mohamed F. Alajmi ◽  
Karima Elkarrach ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Organic Matter ◽  
Microbiological Analysis ◽  
Least Squares Regression ◽  
X Ray Diffraction ◽  
Compost Maturity ◽  
X Ray ◽  
Physical Chemical ◽  
Scanning Electron

To date, compost maturation monitoring is carried out by physical-chemical and microbiological analysis, which could be considered an overweening consumption of time and products. Nowadays, spectroscopy is chosen as a simple tool for monitoring compost maturity. In the present investigation, spectroscopy analysis was performed in the interest of corroborating the compost maturity. This goal was achieved by using the X-ray diffraction, infrared spectroscopy, and scanning electron microscopy. X-ray diffraction analysis showed the presence of the cellulose fraction in compost samples. At the same time, the intensity of pics decreased depending on composting time, thus proving that there was organic matter degradation. Infrared and scanning electron microscopy analysis allow for confirming these results. The correlation between spectroscopies analysis and physical-chemical properties was employed by partial least squares-regression (PLS-R) model. PLS-R model was applied to build a model to predict the compost quality depending on the composting time, the results obtained show that all the parameters analysis are well predicted. The current study proposed that final compost was more stabilized compared with the initial feedstock mixture. Ultimately, spectroscopy techniques used allowed us to confirm the physical-chemical results obtained, and both of them depict maturity and stability of the final compost, thus proving that spectral techniques are more reliable, fast, and promising than physical-chemical analyses.

Resistances of Carbon Black and Polymers in Smart Paints for Temperature Sensors

2021 ◽  
Vol 21 (7) ◽  
pp. 3716-3720
Author(s):  
Ju-Hun Ahn ◽  
Dae-San Choi ◽  
Chang-Yull Lee
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Carbon Black ◽  
Temperature Sensors ◽  
Temperature Sensing ◽  
Sem Images ◽  
Electrical Components ◽  
And Control ◽  
Polymer Type ◽  
Scanning Electron

Temperature sensing and control is an important factor to prevent the overheating of mechanical and electrical components in various devices. However, commercialized temperature sensors can be disadvantageous due to their limited shapes. Therefore, we propose a smart paint to solve this issue. In this study, smart paints were produced based on carbon black, and their properties were measured using thermistors. Experiments were conducted to analyze the resistance properties using carbon and four types of polymers. Through the scanning electron microscopy (SEM) images of the mixed paints, it was shown that the resistances were decreased due to the necking phenomena. Furthermore, each paint provides a different temperature coefficient depending on the polymer type.

Scanning Electron Microscopy Studies of Tear of Carboxylated Nitrile Rubber

1982 ◽  
Vol 55 (1) ◽  
pp. 41-50 ◽  
Author(s):  
S. K. Chakraborty ◽  
A. K. Bhowmick ◽  
S. K. De ◽  
B. K. Dhindaw
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Carbon Black ◽  
Scanning Electron Microscope ◽  
Mixed Type ◽  
Nitrile Rubber ◽  
Stick Slip ◽  
Ionic Crosslinks ◽  
Scanning Electron

Abstract Mechanism of tear of unfilled and carbon black filled carboxylated nitrile rubber (XNBR) having metallocarboxylate crosslinks, sulfur-sulfur crosslinks and mixed type crosslinking systems has been studied by Scanning Electron Microscope. Tear proceeds through stick-slip process in the case of gum mixes. The number of tear lines is more in the sulfur crosslinked system, resulting in poor tear strength. Addition of reinforcing carbon black changes the mechanism of tear. The sulfur crosslinked system shows knotty tear, while introduction of ionic crosslinks results in smooth tear presumably due to the large tip diameter reaching the edge of the specimen.

Understanding variations in reservoir porosity in the Eagle Ford Shale using scanning electron microscopy: implications for basin modelling

2020 ◽  
Vol 484 (1) ◽  
pp. 229-239 ◽  
Author(s):  
Mark Osborne ◽  
Herbert Volk
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Organic Matter ◽  
Pore Size ◽  
Source Rocks ◽  
Thermal Maturity ◽  
Eagle Ford Shale ◽  
Eagle Ford ◽  
Basin Modelling ◽  
Scanning Electron

AbstractReliable evaluation of shale-play potential requires robust geological models that can simulate the generation and retention of petroleum, porosity and permeability in source rocks from first principles, and that can be implemented in basin modelling software. To be predictive, such basin models need to be calibrated against observations from real shale plays. A key control on the amount of retained petroleum is the porosity in the shale and the abundance of organic matter. Scanning electron microscopy of argon-ion milled shale samples can potentially reveal systematic variations in the amount of porosity, pore types and distributions across a range of thermal maturities. These observed variations in porosity can be used to calibrate basin modelling outputs and refine predictive models. For these reasons BP has conducted scanning electron microscopy studies of shale plays including the Eagle Ford Shale, a carbonate-rich mudstone sequence of Cenomanian to Turonian age. The results clearly show that the mean pore size decreases as thermal maturity increases and that organic matter-hosted pores are absent in low thermal maturity samples (where vitrinite random reflectance Ro <0.7) and become increasingly more abundant as thermal maturity increases). In moderately mature samples there are organic matter hosted pores that range in pore size from 5 to 500 nm. In highly mature samples, small (<50 nm) organic matter-hosted pores predominate. Our studies reveal that porosity evolution in this organic-rich, fine-grained, carbonate mudrock shows a strong correlation with increasing thermal maturity.

Irradiated rubber composite with nano and micro fillers for mining rock application

2019 ◽  
Vol 107 (8) ◽  
pp. 737-753
Author(s):  
Hanan M. Eyssa ◽  
Wael S. Mohamed ◽  
Mai M. El-Zayat
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermal Properties ◽  
Carbon Black ◽  
Field Emission ◽  
Rubber Matrix ◽  
Styrene Butadiene Rubber ◽  
Mechanical And Thermal Properties ◽  
Butadiene Rubber ◽  
Scanning Electron

Abstract In this work, nanosilica and micro carbon black (CB) as a fillers were used to improve the properties of styrene butadiene rubber/natural rubber blends (SBR/NR) crosslinked by γ radiation. Nanosilica was prepared from silica sand and used as eco-friendly material. These composites were characterized by field emission scanning electron microscopy (FESEM) and the measurements of the physic-mechanical and thermal properties were measured. Field emission scanning electron microscopy showed that the composites reinforced by nanosilica and the measurements of the CB are uniformly dispersed in the blends matrix. The results showed that the physico-mechanical and thermal properties were improved indicating a good interaction between the fillers and rubber matrix. The volume fraction measurements confirmed the formation of crosslinking network structure. Meanwhile, the reinforcement of SBR/NR blend loaded with nanosilica showed improved mechanical than blend loaded with both the nanosilica/carbon black and the CB alone. The highest enhancement was obtained for the three fillers by using a concentration of 35 phr at a dose of 150 kGy of γ-irradiation. Thermogravimetric analysis (TGA) indicated that the thermal stability of SBR/NR blend reinforced by nanosilica is higher than those blends reinforced with combined filler the silica. It was also found that the irradiated SBR/NR nanocomposites were more stable than the un-irradiated ones.

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