Multi‐Scale Imaging of Polymer Electrolyte Fuel Cells using X‐ray Micro‐ and Nano‐Computed Tomography, Transmission Electron Microscopy and Helium‐Ion Microscopy

Er2Sn2O7 pyrochlore was irradiated with swift heavy Au ions (2.2 GeV), and the induced structural modifications were systematically examined using complementary characterization techniques including transmission electron microscopy (TEM), X-ray diffraction...

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Дозовая зависимость формирования нанокристаллов в имплантированных гелием слоях кремния

Письма в журнал технической физики ◽

10.21883/pjtf.2018.07.45883.17112 ◽

2018 ◽

Vol 44 (7) ◽

pp. 39

Author(s):

А.А. Ломов ◽

А.В. Мяконьких ◽

Ю.М. Чесноков ◽

В.В. Денисов ◽

А.Н. Кириченко ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Silicon Nanocrystals ◽

Implantation Dose ◽

X Ray ◽

Transmission Electron ◽

Helium Ion ◽

Nanocrystal Formation ◽

20 Nm ◽

First Time

AbstractThe possibility of nanocrystal formation in silicon layers subjected to plasma-immersion helium-ion implantation at an energy of 5 keV has been proved for the first time. The effect of the implantation dose on the microstructure of the layers has been studied by X-ray reflectometry, transmission electron microscopy and Raman scattering. It has been established that the formation of silicon nanocrystals with dimensions of 10–20 nm is accompanied by a pronounced dependence on the ion flux and occurs at a dose of 5 × 10^17 cm^–2 with subsequent annealing at 700–800°C. The excessive dose has been shown to cause the destruction of the upper protective sublayer and the degradation of the optical properties of nanocrystals.

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Micro- and Nanometric Characterization of the Celestite Skeleton of Acantharian Species (Radiolaria, Rhizaria)

10.21203/rs.3.rs-1091014/v1 ◽

2021 ◽

Author(s):

Rina Fujimaki ◽

Noritoshi Suzuki ◽

Katsunori Kimoto ◽

Yukiko Nagai ◽

Yuya Oaki ◽

...

Keyword(s):

Electron Microscopy ◽

Computed Tomography ◽

Transmission Electron Microscopy ◽

Raman Spectroscopy ◽

Sea Water ◽

X Ray ◽

Transmission Electron ◽

Regular Arrangement ◽

X Ray Computed

Abstract We studied the micrometric morphology and nanometric structure of the celestite (SrSO4) skeleton of acantharian family Acanthometridae. A body of the skeleton composed of 20 radial spines with four blades was characterized using microfocus X-ray computed tomography. The regular arrangement of three types of spines was clarified with the connection of the blades around the root of each spine. The surface of the spines was covered with a chitin-based organic membrane to prevent dissolution in sea water. On the nanometric scale, the mesocrystalline structure that consists of nanoscale grains having a distorted single-crystal nature was revealed using scanning and transmission electron microscopy, electron diffraction, and Raman spectroscopy. The acantharian skeletons have a crystallographically controlled architecture that is covered with a protective organic membrane.

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Phase Transformations in Ti-7w/oMo-3w/oMe Alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052584 ◽

1974 ◽

Vol 32 ◽

pp. 514-515

Author(s):

S. Fujishiro

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Transmission Electron Microscopy ◽

Tensile Strength ◽

Mechanical Processing ◽

Ray Method ◽

X Ray ◽

Transmission Electron ◽

Water Quench ◽

Alpha Beta

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.

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A High Resolution Study of G.P. Zones in Aluminum - 4.2 at % Silver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055904 ◽

1982 ◽

Vol 40 ◽

pp. 722-723 ◽

Cited By ~ 1

Author(s):

R. Gronsky

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Computer Simulations ◽

Structural Characteristics ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Resolution Study

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.

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Magnesium and sulfur in mast cell and basophil granules of lower vertebrates in relation with histamine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132613 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1596-1597

Author(s):

Kenichi Takaya

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Mast Cell ◽

Mast Cells ◽

Tree Frog ◽

X Ray ◽

Transmission Electron ◽

Scanning Transmission ◽

Fresh Frozen ◽

Ultrathin Sections

Mast cell and basophil granules of the vertebrate contain heparin or related sulfated proteoglycans. Histamine is also present in mammalian mast cells and basophils. However, no histamine is detected in mast cell granules of the amphibian or fish, while it is shown in those of reptiles and birds A quantitative x-ray microanalysis of mast cell granules of fresh frozen dried ultrathin sections of the tongue of Wistar rats and tree frogs disclosed high concentrations of sulfur in rat mast cell granules and those of sulfur and magnesium in the tree frog granules. Their concentrations in tree frog mast cell granules were closely correlated (r=0.94).Fresh frozen dried ultrathin sections and fresh air-dried prints of the tree frog tongue and spleen and young red-eared turtle (ca. 6 g) spleen and heart blood were examined by a quantitative energy-dispersive x-ray microanalysis (X-650, Kevex-7000) for the element constituents of the granules of mast cells and basophils. The specimens were observed by transmission electron microscopy (TEM) (80-200 kV) and followed by scanning transmission electron microscopy (STEM) under an analytical electron microscope (X-650) at an acceleration voltage of 40 kV and a specimen current of 0.2 nA. A spot analysis was performed in a STEM mode for 100 s at a specimen current of 2 nA on the mast cell and basophil granules and other areas of the cells. Histamine was examined by the o-phthalaldehyde method.

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STUDY OF NUCLEATION PROCESS IN (SiO2, Al2O3, Li2O) GLASSES, BY X-RAY ABSORPTION SPECTROSCOPY AND TRANSMISSION ELECTRON MICROSCOPY

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1985876 ◽

1985 ◽

Vol 46 (C8) ◽

pp. C8-491-C8-494 ◽

Cited By ~ 1

Author(s):

A. Ramos ◽

M. Gandais ◽

J. Petiau

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Absorption Spectroscopy ◽

Nucleation Process ◽

X Ray ◽

Transmission Electron ◽

X Ray Absorption

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Quartz Crystallite Size and Moganite Content as Indicators of the Mineralogical Maturity of the Carboniferous Chert: The Case of Cherts from Eastern Asturias (Spain)

Minerals ◽

10.3390/min11060611 ◽

2021 ◽

Vol 11 (6) ◽

pp. 611

Author(s):

Celia Marcos ◽

María de Uribe-Zorita ◽

Pedro Álvarez-Lloret ◽

Alaa Adawy ◽

Patricia Fernández ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Crystallite Size ◽

Archaeological Sites ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Infrared And Raman Spectroscopy ◽

First Time ◽

Geological Formations

Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.

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Revisiting the Bøggild Intergrowth in Iridescent Labradorite Feldspars: Ordering, Kinetics, and Phase Equilibria

Minerals ◽

10.3390/min11070727 ◽

2021 ◽

Vol 11 (7) ◽

pp. 727

Author(s):

Shiyun Jin ◽

Huifang Xu ◽

Seungyeol Lee

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Atom Probe ◽

Phase Region ◽

Two Phase ◽

Subsolidus Phase ◽

Plagioclase Feldspar ◽

X Ray ◽

Transmission Electron ◽

Scanning Transmission

The enigmatic Bøggild intergrowth in iridescent labradorite crystals was revisited in light of recent work on the incommensurately modulated structures in the intermediated plagioclase. Five igneous samples and one metamorphic labradorite sample with various compositions and lamellar thicknesses were studied in this paper. The lamellar textures were characterized with conventional transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). The compositions of individual lamellae were analyzed with high-resolution energy-dispersive X-ray spectroscopy (EDS) mapping and atom probe tomography (APT). The average structure states of the studied samples were also compared with single-crystal X-ray diffraction data (SC-XRD). The Na-rich lamellae have a composition of An44–48, and the Ca-rich lamellae range from An56 to An63. Significant differences between the lamellar compositions of different samples were observed. The compositions of the Bøggild intergrowth do not only depend on the bulk compositions, but also on the thermal history of the host rock. The implications on the subsolidus phase relationships of the plagioclase feldspar solid solution are discussed. The results cannot be explained by a regular symmetrical solvus such as the Bøggild gap, but they support an inclined two-phase region that closes at low temperature.

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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 ◽

10.3390/nano11040921 ◽

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.

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