Incorporation of Various Nanoclays in Semi-refined Carrageenan Film Composite

Abstract In current investigation, various commercial nanoclays with different level of hydrophilicity i.e., hydrophilic bentonite (HB), cloisite 10A, and cloisite® 30B were incorporated to a hydrophilic semi-refined carrageenan (SRC) films to observe their presence in film matrix in regards with the final film’s properties. High shear mixing and sonication were applied to the film preparation to obtain high dispersion of nanoclays in the matrix. As expected, the hydrophilic clay showed better dispersion within the matrix as shown in Energy Dispersive X-Ray Spectroscopy (EDS) image. The more hydrophilic clay inclusion resulted in higher tensile strength, while the more hydrophobic resulted in higher stiffness of the films. The water vapour permeability was decreased in corresponded to the more hydrophobic clay incorporated, and the thermal properties of the films were overall enhanced by the nanoclays reinforcement. In general, nanoclays incorporation in SRC film improved the overall properties of the SRC film.

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Lateral resolution of the electron microbeam analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109859 ◽

1978 ◽

Vol 36 (1) ◽

pp. 542-543

Author(s):

H.J. Dudek

Keyword(s):

Quantitative Analysis ◽

Depth Resolution ◽

Lateral Resolution ◽

Cylindrical Particle ◽

Correction Procedure ◽

X Ray ◽

Element Concentrations ◽

Microbeam Analysis ◽

The Matrix

The chemical inhomogenities in modern materials such as fibers, phases and inclusions, often have diameters in the region of one micrometer. Using electron microbeam analysis for the determination of the element concentrations one has to know the smallest possible diameter of such regions for a given accuracy of the quantitative analysis.In th is paper the correction procedure for the quantitative electron microbeam analysis is extended to a spacial problem to determine the smallest possible measurements of a cylindrical particle P of high D (depth resolution) and diameter L (lateral resolution) embeded in a matrix M and which has to be analysed quantitative with the accuracy q. The mathematical accounts lead to the following form of the characteristic x-ray intens ity of the element i of a particle P embeded in the matrix M in relation to the intensity of a standard S

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Analysis and lattice imaging of a transitional event on garnets

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108490 ◽

1978 ◽

Vol 36 (1) ◽

pp. 270-271

Author(s):

J.Y. Laval

Keyword(s):

Yttrium Iron Garnet ◽

Reciprocal Lattice ◽

Transitional Zone ◽

Lattice Imaging ◽

Yttrium Iron ◽

X Ray ◽

Ionic Process ◽

The Matrix ◽

High Resolution Technique ◽

Iron Garnet

The exsolution of magnetite from a substituted Yttrium Iron Garnet, containing an iron excess may lead to a transitional event. This event is characterized hy the formation of a transitional zone at the center of which the magnetite nucleates (Fig.1). Since there is a contrast between the matrix and these zones and since selected area diffraction does not show any difference between those zones and the matrix in the reciprocal lattice, it is of interest to analyze the structure of the transitional zones.By using simultaneously different techniques in electron microscopy, (oscillating crystal method microdiffraction and X-ray microanalysis)one may resolve the ionic process corresponding to the transitional event and image this event subsequently by high resolution technique.

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Phase identification in SiC whisker reinforced Al2O3-R2O3-based composites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100121168 ◽

1992 ◽

Vol 50 (1) ◽

pp. 152-153

Author(s):

C.M. Sung ◽

K.J. Ostreicher ◽

M.L. Huckabee ◽

S.T. Buljan

Keyword(s):

Analytical Electron Microscopy ◽

Phase Identification ◽

Reinforced Composites ◽

Ion Milling ◽

X Ray ◽

Binary Oxides ◽

Analytical Electron ◽

The Matrix ◽

Second Phases ◽

Convergent Beam

A series of binary oxides and SiC whisker reinforced composites both having a matrix composed of an α-(Al, R)2O3 solid solution (R: rare earth) have been studied by analytical electron microscopy (AEM). The mechanical properties of the composites as well as crystal structure, composition, and defects of both second phases and the matrix were investigated. The formation of various second phases, e.g. garnet, β-Alumina, or perovskite structures in the binary Al2O3-R2O3 and the ternary Al2O3-R2O3-SiC(w) systems are discussed.Sections of the materials having thicknesses of 100 μm - 300 μm were first diamond core drilled. The discs were then polished and dimpled. The final step was ion milling with Ar+ until breakthrough occurred. Samples prepared in this manner were then analyzed using the Philips EM400T AEM. The low-Z energy dispersive X-ray spectroscopy (EDXS) data were obtained and correlated with convergent beam electron diffraction (CBED) patterns to identify phase compositions and structures. The following EDXS parameters were maintained in the analyzed areas: accelerating voltage of 120 keV, sample tilt of 12° and 20% dead time.

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Improving x-ray map resolution with image restoration techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100165458 ◽

1996 ◽

Vol 54 ◽

pp. 598-599

Author(s):

Richard B. Mott ◽

John J. Friel ◽

Charles G. Waldman

Keyword(s):

Image Restoration ◽

Hubble Space Telescope ◽

Extensive Literature ◽

Small Object ◽

X Rays ◽

X Ray ◽

Mapping Parameters ◽

The Matrix ◽

The 1960S ◽

Map Resolution

X-rays are emitted from a relatively large volume in bulk samples, limiting the smallest features which are visible in X-ray maps. Beam spreading also hampers attempts to make geometric measurements of features based on their boundaries in X-ray maps. This has prompted recent interest in using low voltages, and consequently mapping L or M lines, in order to minimize the blurring of the maps.An alternative strategy draws on the extensive work in image restoration (deblurring) developed in space science and astronomy since the 1960s. A recent example is the restoration of images from the Hubble Space Telescope prior to its new optics. Extensive literature exists on the theory of image restoration. The simplest case and its correspondence with X-ray mapping parameters is shown in Figures 1 and 2.Using pixels much smaller than the X-ray volume, a small object of differing composition from the matrix generates a broad, low response. This shape corresponds to the point spread function (PSF). The observed X-ray map can be modeled as an “ideal” map, with an X-ray volume of zero, convolved with the PSF. Figure 2a shows the 1-dimensional case of a line profile across a thin layer. Figure 2b shows an idealized noise-free profile which is then convolved with the PSF to give the blurred profile of Figure 2c.

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Possible Pitfalls in the Analysis of Minerals and Loose Materials by Portable XRF, and How to Overcome Them

Minerals ◽

10.3390/min11010033 ◽

2020 ◽

Vol 11 (1) ◽

pp. 33

Author(s):

Valérie Laperche ◽

Bruno Lemière

Keyword(s):

Fluorescence Spectroscopy ◽

Laboratory Data ◽

Data Sets ◽

Light Elements ◽

Portable Xrf ◽

X Ray ◽

Protective Films ◽

The Matrix ◽

Valuable Complement ◽

Physical Effects

Portable X-ray fluorescence spectroscopy is now widely used in almost any field of geoscience. Handheld XRF analysers are easy to use, and results are available in almost real time anywhere. However, the results do not always match laboratory analyses, and this may deter users. Rather than analytical issues, the bias often results from sample preparation differences. Instrument setup and analysis conditions need to be fully understood to avoid reporting erroneous results. The technique’s limitations must be kept in mind. We describe a number of issues and potential pitfalls observed from our experience and described in the literature. This includes the analytical mode and parameters; protective films; sample geometry and density, especially for light elements; analytical interferences between elements; physical effects of the matrix and sample condition, and more. Nevertheless, portable X-ray fluorescence spectroscopy (pXRF) results gathered with sufficient care by experienced users are both precise and reliable, if not fully accurate, and they can constitute robust data sets. Rather than being a substitute for laboratory analyses, pXRF measurements are a valuable complement to those. pXRF improves the quality and relevance of laboratory data sets.

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A New Methodological Approach to Correlate Protective and Microscopic Properties by Soft X-ray Microscopy and Solid State NMR Spectroscopy: The Case of Cusa’s Stone

Applied Sciences ◽

10.3390/app11135767 ◽

2021 ◽

Vol 11 (13) ◽

pp. 5767

Author(s):

Veronica Ciaramitaro ◽

Alberto Spinella ◽

Francesco Armetta ◽

Roberto Scaffaro ◽

Emmanuel Fortunato Gulino ◽

...

Keyword(s):

Solid State ◽

Nmr Spectroscopy ◽

Solid State Nmr ◽

Methodological Approach ◽

Polymer Chains ◽

General Question ◽

Protective Agent ◽

Vapour Permeability ◽

X Ray ◽

Solid State Nmr Spectroscopy

Hydrophobic treatment is one of the most important interventions usually carried out for the conservation of stone artefacts and monuments. The study here reported aims to answer a general question about how two polymers confer different protective performance. Two fluorinated-based polymer formulates applied on samples of Cusa’s stone confer a different level of water repellence and water vapour permeability. The observed protection action is here explained on the basis of chemico-physical interactions. The distribution of the polymer in the pore network was investigated using scanning electron microscopy and X-ray microscopy. The interactions between the stone substrate and the protective agents were investigated by means of solid state NMR spectroscopy. The ss-NMR findings reveal no significant changes in the chemical neighbourhood of the observed nuclei of each protective agent when applied onto the stone surface and provide information on the changes in the organization and dynamics of the studied systems, as well as on the mobility of polymer chains. This allowed us to explain the different macroscopic behaviours provided by each protective agent to the stone substrate.

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Embracing Uncertainty: Modeling Uncertainty in EPMA—Part II

Microscopy and Microanalysis ◽

10.1017/s1431927620024691 ◽

2021 ◽

Vol 27 (1) ◽

pp. 74-89

Author(s):

Nicholas W.M. Ritchie

Keyword(s):

Beam Energy ◽

Uncertainty Modeling ◽

Matrix Correction ◽

Correction Model ◽

X Ray ◽

Starting Point ◽

Uncertainty Calculation ◽

The Matrix ◽

Measurement Design ◽

New Framework

AbstractThis, the second in a series of articles present a new framework for considering the computation of uncertainty in electron excited X-ray microanalysis measurements, will discuss matrix correction. The framework presented in the first article will be applied to the matrix correction model called “Pouchou and Pichoir's Simplified Model” or simply “XPP.” This uncertainty calculation will consider the influence of beam energy, take-off angle, mass absorption coefficient, surface roughness, and other parameters. Since uncertainty calculations and measurement optimization are so intimately related, it also provides a starting point for optimizing accuracy through choice of measurement design.

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Expanded vermiculite-filled flexible polymer composites

Journal of Elastomers & Plastics ◽

10.1177/00952443211029038 ◽

2021 ◽

pp. 009524432110290

Author(s):

Mukaddes Sevval Cetin ◽

Ozan Toprakci ◽

Omer Suat Taskin ◽

Abdullah Aksu ◽

Hatice Aylin Karahan Toprakci

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Contact Angle ◽

Polymer Composites ◽

Flame Retardancy ◽

Composite Films ◽

Filler Concentration ◽

High Shear ◽

Flexible Polymer ◽

Shear Mixing

This study focuses on the fabrication and characterization of vermiculite-filled flexible polymer composites. Exfoliated vermiculite was incorporated into triblock thermoplastic elastomer copolymer, styrene- b-(ethylene- co-butylene)- b-styrene (SEBS), at various levels from 1 to 15 wt% by a high shear mixer. The composite films were obtained by the combination of solvent casting and compression molding. The morphological, structural, thermal, and mechanical properties and contact angle of the composites were determined. Some micro-morphological differences were observed between the samples and the difference was assumed to be caused by high shear mixing and filler concentration. High shear mixing was found effective in terms of the detachment of vermiculite layers at all concentrations. However, at low filler loading, that behavior was more obvious. At 1 wt% filler concentration, mechanical properties increased that was probably caused by good filler-matrix interaction stemmed from smaller particle size. At higher vermiculite concentrations, fillers found to show agglomerations that led to a decrease in mechanical strength and strain at break. Elastic and secant modulus showed an increasing trend. Contact angle measurements were carried out to determine the oleophilic character of the samples. An increase in the vermiculite content resulted in higher oleophilic character and the lowest contact angle was obtained at 15 wt% VMT loading. In addition to these, thermal stability, thermal dimensional stability and flame retardancy were improved by the incorporation of VMT. 15 wt% vermiculite-filled sample showed the best performance in terms of thermal stability and flame retardancy.

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