Supplemental Material: Clay templates in Ediacaran vendotaeniaceans: Implications for the taphonomy of carbonaceous fossils

It is well established that unique physiological information can be obtained by rapidly freezing cells in various functional states and analyzing the cell element content and distribution by electron probe x-ray microanalysis. (The other techniques of microanalysis that are amenable to imaging, such as electron energy loss spectroscopy, secondary ion mass spectroscopy, particle induced x-ray emission etc., are not addressed in this tutorial.) However, the usual processes of data acquisition are labor intensive and lengthy, requiring that x-ray counts be collected from individually selected regions of each cell in question and that data analysis be performed subsequent to data collection. A judicious combination of quantitative elemental maps and static raster probes adds not only an additional overall perception of what is occurring during a particular biological manipulation or event, but substantially increases data productivity. Recent advances in microcomputer instrumentation and software have made readily feasible the acquisition and processing of digital quantitative x-ray maps of one to several cells.

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Simulation of the XRD patterns, structural properties of a synthetic Na-Hectorite exchanged Cu2+and Ca2+

Zeitschrift für Kristallographie ◽

10.1524/zkri.2007.2007.suppl_26.503 ◽

2007 ◽

Vol 2007 (suppl_26) ◽

pp. 503-508

Author(s):

M. S. Karmous ◽

W. Oueslati ◽

H. Ben Rhaiem ◽

J. L. Robert ◽

A. Ben Haj Amara

Keyword(s):

Structural Properties ◽

Xrd Patterns

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Structural and Magnetic Hysteresis Properties of Co-Zr Substituted Hexagonal Barium Ferrites

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v7i1.1739 ◽

2015 ◽

Vol 7 (1) ◽

pp. 1346-1351

Author(s):

Ch.Gopal Reddy ◽

Ch. Venkateshwarlu ◽

P. Vijaya Bhasker Reddy

Keyword(s):

Magnetic Properties ◽

Single Phase ◽

Magnetic Hysteresis ◽

Grain Morphology ◽

Hexagonal Structure ◽

Ion Composition ◽

X Ray Diffraction ◽

Ceramic Method ◽

Barium Ferrites ◽

Xrd Patterns

Co-Zr substituted M-type hexagonal barium ferrites, with chemical formula BaCoxZrxFe12-2xO19 (where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), have been synthesized by double sintering ceramic method. The crystallographic properties, grain morphology and magnetic properties of these ferrites have been investigated by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM). The XRD patterns confirm the single phase with hexagonal structure of prepared ferrites. The magnetic properties have been investigated as a function of Co and Zr ion composition at an applied field in the range of 20 KOe. These studies indicate that the saturation magnetization (Ms) in the samples increases initially up to the Co-Zr composition of x=0.6 and decreases thereafter. On the other hand, the coercivity (Hc) and Remanent magnetization (Mr) are found to decrease continuously with increasing Co-Zr content. This property is most useful in permanent magnetic recording. The observed results are explained on the basis of site occupation of Co and Zr ions in the samples.

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3D Observation of Elemental Distribution of Si-Device using a Dedicated FIB/STEM System

ISTFA 2005: Conference Proceedings from the 31st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2005p0382 ◽

2005 ◽

Author(s):

T. Yaguchi ◽

M. Konno ◽

T. Kamino ◽

M. Ogasawara ◽

K. Kaji ◽

...

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Three Dimensional ◽

Elemental Distribution ◽

Multivariate Statistical ◽

X Ray ◽

Sample Rotation ◽

Transmission Electron ◽

Scanning Transmission ◽

Elemental Maps

Abstract A technique for preparation of a pillar shaped sample and its multi-directional observation of the sample using a focused ion beam (FIB) / scanning transmission electron microscopy (STEM) system has been developed. The system employs an FIB/STEM compatible sample rotation holder with a specially designed rotation mechanism, which allows the sample to be rotated 360 degrees [1-3]. This technique was used for the three dimensional (3D) elemental mapping of a contact plug of a Si device in 90 nm technology. A specimen containing a contact plug was shaped to a pillar sample with a cross section of 200 nm x 200 nm and a 5 um length. Elemental analysis was performed with a 200 kV HD-2300 STEM equipped with the EDAX genesis Energy dispersive X-ray spectroscopy (EDX) system. Spectrum imaging combined with multivariate statistical analysis (MSA) [4, 5] was used to enhance the weak X-ray signals of the doped area, which contain a low concentration of As-K. The distributions of elements, especially the dopant As, were successfully enhanced by MSA. The elemental maps were .. reconstructed from the maps.

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Structural and morphological characterization of CdS nanoparticles

Current Physical Chemistry ◽

10.2174/1877946810999200730222025 ◽

2020 ◽

Vol 10 ◽

Author(s):

Manish Dwivedi ◽

Vijay Tripathi ◽

Dhruv Kumar ◽

Dwijendra K. Gupta

Keyword(s):

Blue Shift ◽

Chemical Precipitation ◽

Morphological Characterization ◽

Precipitation Method ◽

Cds Nanoparticles ◽

Cubic Phase ◽

Simple Chemical ◽

Xrd Patterns ◽

Average Size ◽

Physical Tools

Aims: CdS nanoparticles are an attractive material having application in various field like as pigment in paints, biotag for bioimaging and many more optoelectronic as well as biological applications. Present study aims to synthesize and characterize the CdS nanoparticles to make it applicable in different areas Objectives: Preparation CdS nanoparticles by using simple and facile chemical methods and further physical and structural characterization using various physical tools Methods: In present work CdS nanoparticles has been synthesized by using rationally simple chemical precipitation method with some modi-fication on temperature and incubation time in existed methods. Characterizations were done by employing XRD, SEM, TEM, AFM tech-niques Results: Simple chemical method produces the CdS nanoparticles with the size about 100-200 nm in length and 5-10 nm in diameter. The SEM studies show that the CdS nanoparticles can agglomerate and form a continuous network like structure. The X-ray diffraction (XRD) measurements show the single-phase formation of CdS nanoparticles with the structure of cubic phase, and the broadening of XRD patterns indicates that the prepared samples are nanostructured. Our analysis on CdS nanoparticles by using transmission electron microscope and atomic force microscope (AFM) revealed that the nanoparticles form both spherical and nearly rod shaped with the average size applicable for biotagging. UV-Vis spectroscopic analysis reveals blue shift in the absorption peak probably caused by quantum confinement Conclusion: The observed CdS nanoparticles were appeared yellow in color. The XRD pattern of the CdS nanoparticles showed that the materials were of nanometric sized regime with a predominantly cubic phase along with the rod and round morphology. The study and char-acterization of CdS nanoparticles will bring us a new approach to understand biological problem by tagging nanoparticles with biomolecules and further suggests that the CdS nanoparticles formulate it more suitable biocompatible nanomaterial for biotagging and bioimaging

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A Tilting Procedure to Enhance Compositional Contrast and Reduce Residual Bragg Contrast in EFTEM Imaging of Planar Interfaces

Microscopy and Microanalysis ◽

10.1017/s1431927600033274 ◽

2000 ◽

Vol 6 (S2) ◽

pp. 156-157

Author(s):

K.T. Moore ◽

E.A. Stach ◽

J.M. Howe ◽

D.C. Elbert ◽

D.R. Veblen

Keyword(s):

Electron Scattering ◽

Planar Interface ◽

Zone Axis ◽

Crystalline Material ◽

Energy Losses ◽

Inelastic Electron ◽

Diffraction Contrast ◽

Background Removal ◽

Intensity Changes ◽

Elemental Maps

When acquiring energy-filtered TEM (EFTEM) images of a crystalline material, the detrimental effects of diffraction contrast can often be seen in raw energy-filtered images (EFI) (i.e., pre-edge and post-edge images), jump-ratio images and elemental maps as residual diffraction contrast. Residual diffraction contrast occurs in raw EFI because of plural scattering (i.e., inelastic-elastic and elastic-inelastic electron scattering) and in jump-ratio images and elemental maps because background removal procedures often are unable to completely account for intensity changes due to dynamical effects (elastic scattering) that occur between pre-edge and post-edge images acquired at different energy losses.It is demonstrated in these experiments that, when examining a planar interface, EFTEM images have increased compositional contrast and decreased residual diffraction contrast when the sample is oriented so that the interface is parallel to the electron beam, but not directly on a zone axis.

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Hydrothermally Assisted Fabrication of TiO2-Fe3O4 Composite Materials and Their Antibacterial Activity

Materials ◽

10.3390/ma13214715 ◽

2020 ◽

Vol 13 (21) ◽

pp. 4715

Author(s):

Adam Kubiak ◽

Marta Kubacka ◽

Elżbieta Gabała ◽

Anna Dobrowolska ◽

Karol Synoradzki ◽

...

Keyword(s):

Antibacterial Activity ◽

Composite Materials ◽

Bet Surface Area ◽

Molar Ratio ◽

Oxide Content ◽

Gram Positive ◽

Gram Negative ◽

Transmission Electron ◽

Xrd Patterns ◽

Oxide Composites

The TiO2-Fe3O4 composite materials were fabricated via the hydrothermal-assisted technique. It was determined how the molar ratio of TiO2 to Fe3O4 influences the crystalline structure and morphology of the synthesized composite materials. The effect of the molar ratio of components on the antibacterial activity was also analyzed. On the basis of XRD patterns for the obtained titanium(IV) oxide-iron(II, III) oxide composites, the two separate crystalline forms—anatase and magnetite —were observed. Transmission electron microscopy revealed particles of cubic and tetragonal shape for TiO2 and spherical for Fe3O4. The results of low-temperature nitrogen sorption analysis indicated that an increase in the iron(II, III) oxide content leads to a decrease in the BET surface area. Moreover, the superparamagnetic properties of titanium(IV) oxide-iron(II, III) oxide composites should be noted. An important aim of the work was to determine the antibacterial activity of selected TiO2-Fe3O4 materials. For this purpose, two representative strains of bacteria, the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, were used. The titanium(IV) oxide-iron(II, III) oxide composites demonstrated a large zone of growth inhibition for both Gram-positive and Gram-negative bacteria. Moreover, it was found that the analyzed materials can be reused as antibacterial agents in three consecutive cycles with good results.

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Comparison of Spectroscopic Techniques Combined with Chemometrics for Cocaine Powder Analysis

Journal of Analytical Toxicology ◽

10.1093/jat/bkaa101 ◽

2020 ◽

Vol 44 (8) ◽

pp. 851-860

Author(s):

Joy Eliaerts ◽

Natalie Meert ◽

Pierre Dardenne ◽

Vincent Baeten ◽

Juan-Antonio Fernandez Pierna ◽

...

Keyword(s):

Gas Chromatography ◽

Near Infrared ◽

Evaluation Criteria ◽

Classification Model ◽

Support Vector ◽

Spectroscopic Techniques ◽

Data Set ◽

Promising Tool ◽

Powder Analysis ◽

Mir Spectra

Abstract Spectroscopic techniques combined with chemometrics are a promising tool for analysis of seized drug powders. In this study, the performance of three spectroscopic techniques [Mid-InfraRed (MIR), Raman and Near-InfraRed (NIR)] was compared. In total, 364 seized powders were analyzed and consisted of 276 cocaine powders (with concentrations ranging from 4 to 99 w%) and 88 powders without cocaine. A classification model (using Support Vector Machines [SVM] discriminant analysis) and a quantification model (using SVM regression) were constructed with each spectral dataset in order to discriminate cocaine powders from other powders and quantify cocaine in powders classified as cocaine positive. The performances of the models were compared with gas chromatography coupled with mass spectrometry (GC–MS) and gas chromatography with flame-ionization detection (GC–FID). Different evaluation criteria were used: number of false negatives (FNs), number of false positives (FPs), accuracy, root mean square error of cross-validation (RMSECV) and determination coefficients (R2). Ten colored powders were excluded from the classification data set due to fluorescence background observed in Raman spectra. For the classification, the best accuracy (99.7%) was obtained with MIR spectra. With Raman and NIR spectra, the accuracy was 99.5% and 98.9%, respectively. For the quantification, the best results were obtained with NIR spectra. The cocaine content was determined with a RMSECV of 3.79% and a R2 of 0.97. The performance of MIR and Raman to predict cocaine concentrations was lower than NIR, with RMSECV of 6.76% and 6.79%, respectively and both with a R2 of 0.90. The three spectroscopic techniques can be applied for both classification and quantification of cocaine, but some differences in performance were detected. The best classification was obtained with MIR spectra. For quantification, however, the RMSECV of MIR and Raman was twice as high in comparison with NIR. Spectroscopic techniques combined with chemometrics can reduce the workload for confirmation analysis (e.g., chromatography based) and therefore save time and resources.

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Green Synthesis of Copper Nanoparticles Using Cotton

Polymers ◽

10.3390/polym13121906 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1906

Author(s):

Marissa Pérez-Alvarez ◽

Gregorio Cadenas-Pliego ◽

Odilia Pérez-Camacho ◽

Víctor E. Comparán-Padilla ◽

Christian J. Cabello-Alvarado ◽

...

Keyword(s):

Green Synthesis ◽

Copper Nanoparticles ◽

Uv Spectroscopy ◽

Synthesis Method ◽

Crystallinity Index ◽

Reaction Conditions ◽

New Synthesis ◽

Water As Solvent ◽

Characterization Studies ◽

Xrd Patterns

Copper nanoparticles (CuNP) were obtained by a green synthesis method using cotton textile fibers and water as solvent, avoiding the use of toxic reducing agents. The new synthesis method is environmentally friendly, inexpensive, and can be implemented on a larger scale. This method showed the cellulose capacity as a reducing and stabilizing agent for synthetizing Cellulose–Copper nanoparticles (CCuNP). Nanocomposites based on CCuNP were characterized by XRD, TGA, FTIR and DSC. Functional groups present in the CCuNP were identified by FTIR analysis, and XRD patterns disclosed that nanoparticles correspond to pure metallic Cu°, and their sizes are at a range of 13–35 nm. Results demonstrated that CuNPs produced by the new method were homogeneously distributed on the entire surface of the textile fiber, obtaining CCuNP nanocomposites with different copper wt%. Thus, CuNPs obtained by this method are very stable to oxidation and can be stored for months. Characterization studies disclose that the cellulose crystallinity index (CI) is modified in relation to the reaction conditions, and its chemical structure is destroyed when nanocomposites with high copper contents are synthesized. The formation of CuO nanoparticles was confirmed as a by-product, through UV spectroscopy, in the absorbance range of 300–350 nm.

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