Xafs Studies of Cr-Si-O Interfaces with Al and Polyimide by using Synchrotron Radiation

1991 ◽  
Vol 238 ◽  
Author(s):  
Kiyoshi Ogata ◽  
Asao Nakano ◽  
Yasunori Narizuka ◽  
Takayoshi Watanabe ◽  
Tetsuya Yamazaki
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Heat Treatment ◽  
Transmission Electron Microscopy ◽  
Synchrotron Radiation ◽  
Amorphous Structure ◽  
Structure Change ◽  
Chemical Analyses ◽  
X Ray ◽  
Transmission Electron

ABSTRACTThe structure change of a Cr-Si-O thin film with regard to heat-treatment was investigated not only by the transmission XAFS method but by the surface sensitive XAFS method using synchrotron radiation. As a result of transmission XAFS, the Cr-Si-O thin film as sputtered has an amorphous structure like a mixture of SiO2, Cr and CrSix. After heat-treatment to 650 K, Si-Cr bonds decreased and Si-O and Cr-Cr bonds increased. CrSix is unstable in the system. The interfacial studies by the surface XAFS method showed i) at the interface with polyimide, there is a thin layer which is dominantly made of Cr2O3 and ii) at the interface with Al, Cr atoms are mainly coordinated to Cr. Analyses by the XAFS method gave consistent results with chemical analyses by x-ray photoelectron spei roscopy and observation by transmission electron microscopy.

scholarly journals Synchrotron Radiation Spectroscopy and Transmission Electron Microscopy Techniques to Evaluate TiO2 NPs Incorporation, Speciation, and Impact on Root Cells Ultrastructure of Pisum sativum L. Plants

Nanomaterials ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 921
Author(s):  
Simonetta Muccifora ◽  
Hiram Castillo-Michel ◽  
Francesco Barbieri ◽  
Lorenza Bellani ◽  
Monica Ruffini Castiglione ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Synchrotron Radiation ◽  
Pisum Sativum ◽  
Emission Spectrometry ◽  
Root Cells ◽  
Tio2 Nps ◽  
X Ray ◽  
Pisum Sativum L ◽  
Transmission Electron

Biosolids (Bs) for use in agriculture are an important way for introducing and transferring TiO2 nanoparticles (NPs) to plants and food chain. Roots of Pisum sativum L. plants grown in Bs-amended soils spiked with TiO2 800 mg/kg as rutile NPs, anatase NPs, mixture of both NPs and submicron particles (SMPs) were investigated by Transmission Electron Microscopy (TEM), synchrotron radiation based micro X-ray Fluorescence and micro X-ray Absorption Near-Edge Structure (µXRF/µXANES) and Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). TEM analysis showed damages in cells ultrastructure of all treated samples, although a more evident effect was observed with single anatase or rutile NPs treatments. Micro-XRF and TEM evidenced the presence of nano and SMPs mainly in the cortex cells near the rhizodermis. Micro-XRF/micro-XANES analysis revealed anatase, rutile, and ilmenite as the main TiO2 polymorphs in the original soil and Bs, and the preferential anatase uptake by the roots. For all treatments Ti concentration in the roots increased by 38–56%, however plants translocation factor (TF) increased mostly with NPs treatment (261–315%) and less with SMPs (about 85%), with respect to control. In addition, all samples showed a limited transfer of TiO2 to the shoots (very low TF value). These findings evidenced a potential toxicity of TiO2 NPs present in Bs and accumulating in soil, suggesting the necessity of appropriate regulations for the occurrence of NPs in Bs used in agriculture.

scholarly journals Multiscale X-ray phase contrast imaging of human cartilage for investigating osteoarthritis formation

2021 ◽  
Vol 28 (1) ◽  
Author(s):  
Annie Horng ◽  
Johannes Stroebel ◽  
Tobias Geith ◽  
Stefan Milz ◽  
Alexandra Pacureanu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Synchrotron Radiation ◽  
Phase Contrast ◽  
Phase Contrast Imaging ◽  
Contrast Imaging ◽  
Human Cartilage ◽  
X Ray ◽  
Transmission Electron ◽  
Architectural Organization

Abstract Background The evolution of cartilage degeneration is still not fully understood, partly due to its thinness, low radio-opacity and therefore lack of adequately resolving imaging techniques. X-ray phase-contrast imaging (X-PCI) offers increased sensitivity with respect to standard radiography and CT allowing an enhanced visibility of adjoining, low density structures with an almost histological image resolution. This study examined the feasibility of X-PCI for high-resolution (sub-) micrometer analysis of different stages in tissue degeneration of human cartilage samples and compare it to histology and transmission electron microscopy. Methods Ten 10%-formalin preserved healthy and moderately degenerated osteochondral samples, post-mortem extracted from human knee joints, were examined using four different X-PCI tomographic set-ups using synchrotron radiation the European Synchrotron Radiation Facility (France) and the Swiss Light Source (Switzerland). Volumetric datasets were acquired with voxel sizes between 0.7 × 0.7 × 0.7 and 0.1 × 0.1 × 0.1 µm3. Data were reconstructed by a filtered back-projection algorithm, post-processed by ImageJ, the WEKA machine learning pixel classification tool and VGStudio max. For correlation, osteochondral samples were processed for histology and transmission electron microscopy. Results X-PCI provides a three-dimensional visualization of healthy and moderately degenerated cartilage samples down to a (sub-)cellular level with good correlation to histologic and transmission electron microscopy images. X-PCI is able to resolve the three layers and the architectural organization of cartilage including changes in chondrocyte cell morphology, chondrocyte subgroup distribution and (re-)organization as well as its subtle matrix structures. Conclusions X-PCI captures comprehensive cartilage tissue transformation in its environment and might serve as a tissue-preserving, staining-free and volumetric virtual histology tool for examining and chronicling cartilage behavior in basic research/laboratory experiments of cartilage disease evolution.

scholarly journals One-Step Synthesis of Copper and Cupric Oxide Particles from the Liquid Phase by X-Ray Radiolysis Using Synchrotron Radiation

2016 ◽  
Vol 2016 ◽  
pp. 1-16 ◽  
Author(s):  
Akinobu Yamaguchi ◽  
Ikuo Okada ◽  
Takao Fukuoka ◽  
Mari Ishihara ◽  
Ikuya Sakurai ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Synchrotron Radiation ◽  
Cupric Oxide ◽  
Oxide Particle ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
One Step ◽  
Oxide Particles

The deposition of copper (Cu) and cupric oxide (Cu4O3, Cu2O, and CuO) particles in an aqueous copper sulfate (CuSO4) solution with additive alcohol such as methanol, ethanol, 2-propanol, and ethylene glycol has been studied by X-ray exposure from synchrotron radiation. An attenuated X-ray radiation time of 5 min allows for the synthesis of Cu, Cu4O3, Cu2O, and CuO nano/microscale particles and their aggregation into clusters. The morphology and composition of the synthesized Cu/cupric oxide particle clusters were characterized by scanning electron microscopy, scanning transmission electron microscopy, and high-resolution transmission electron microscopy with energy dispersive X-ray spectroscopy. Micro-Raman spectroscopy revealed that the clusters comprised cupric oxide core particles covered with Cu particles. Neither Cu/cupric oxide particles nor their clusters were formed without any alcohol additives. The effect of alcohol additives is attributed to the following sequential steps: photochemical reaction due to X-ray irradiation induces nucleation of the particles accompanying redox reaction and forms a cluster or aggregates by LaMer process and DLVO interactions. The procedure offers a novel route to synthesize the Cu/cupric oxide particles and aggregates. It also provides a novel additive manufacturing process or lithography of composite materials such as metal, oxide, and resin.

Cross-Sectional TEM Study Of Phase Separation In Reaction Of Ni-Ta Films With GaAs

1985 ◽  
Vol 54 ◽  
Author(s):  
A. Lahav ◽  
M. Eizenberg ◽  
Y. Komem
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Transmission Electron Microscopy ◽  
Phase Separation ◽  
Gaas Substrate ◽  
Auger Spectroscopy ◽  
X Ray Diffraction ◽  
Cross Sectional ◽  
X Ray ◽  
Transmission Electron

ABSTRACTThe reaction between Ni60Ta40 amorphous alloy and (001) GaAs was studied by cross-sectional transmission electron microscopy, Auger spectroscopy, and x-ray diffraction. At 400°C formation of Ni GaAs at the interface with GaAs was observed. After heat treatment at 600°C in vacuum a layered structure of TaAs/NiGa/GaAs has been formed. The NiGa layer has epitaxial relations to the GaAs substrate. The vertical phase separation can be explained by opposite diffusion directions of nickel and arsenic atoms.

Carbonate and cation substitutions in hydroxylapatite in breast cancer micro-calcifications

2021 ◽  
pp. 1-11
Author(s):  
Yan Zhang ◽  
Changqiu Wang ◽  
Yan Li ◽  
Anhuai Lu ◽  
Fanlu Meng ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fourier Transform ◽  
Synchrotron Radiation ◽  
Optical Microscopy ◽  
Fourier Transform Infrared ◽  
X Ray ◽  
Transmission Electron ◽  
Cation Substitutions

Abstract Calcification within breast cancer is a diagnostically significant radiological feature that generally consists of hydroxylapatite. Samples from 30 cases of breast carcinoma with calcification were investigated using optical microscopy, energy-dispersive X-ray analysis, transmission-electron microscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, synchrotron radiation X-ray diffraction and X-ray fluorescence. Under optical microscopy, the calcifications were found to consist of either irregular aggregates with widths > 200 μm or spherical aggregates similar to psammoma bodies with an average diameter of 30 μm. Transmission-electron microscopy showed that short columnar or dumbbell-shaped crystals with widths of 10–15 nm and lengths of 20–50 nm were the most common morphology; spherical aggregates (~1 μm in diameter) with amorphous coatings of fibrous nanocrystals were also observed. Results indicated that hydroxylapatite was the dominant mineral phase in the calcifications, and both CO32– and cation substitutions (Na, Mg, Zn, Fe, Sr, Cu and Mn) were present in the hydroxylapatite structure. Fourier-transform infrared spectra show peaks at 872 and 880 cm–1 indicating that CO32– substituted both the OH– (A type) and PO43– (B type) sites of hydroxylapatite, making it an A and B mixed type. The ratio of B- to A-type substitution was estimated in the range of 1.1–18.7 from the ratio of peak intensities (I872/I880), accompanied with CO32– contents from 1.1% to 14.5%. Trace arsenic, detected in situ by synchrotron radiation X-ray fluorescence was found to be distributed uniformly in the calcifications in the form of AsO43– substituting for PO43–. It is therefore proposed that identifying these trace elements in breast cancer calcifications may be promising for future clinical diagnostics.

Identification of the Failure Mechanism of a Thin Film on a Thick Substrate by Means of Synchrotron X-Ray Topography Combined with Transmission Electron Microscopy

1987 ◽  
Vol 108 ◽  
Author(s):  
D. Goyal ◽  
W. Ng ◽  
A. H. King ◽  
J. C. Bilello
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Film Thickness ◽  
Film Stress ◽  
Silicon Substrates ◽  
X Ray ◽  
Transmission Electron ◽  
Thick Substrate

ABSTRACTWe have used synchrotron x-ray topographic techniques to study the stresses in thin films formed upon silicon substrates either by evaporation or sputtering. It is found that the film stress generally decreases with increasing film thickness for evaporated films, but film delamination occurs at a well defined film thickness. Transmission electron microscope studies have been performed on the same specimens in order to reveal what mechanisms are involved with the delamination of the films.

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