Mineralogy of Pb-P grains in the roots of Agrostis capillaris L. by ATEM and EXAFS

AbstractAnalytical transmission electron microscopy (ATEM) and X-ray absorption spectroscopy (XAS) have been used to determine the mineralogy of Pb-P deposits in the roots of the heavy metal tolerant grass cultivar Agrostis capillaris L. cv. Parys Mountain. The deposits have a pyromorphite (Pb5(PO4)3Cl)-type structure and composition although some of the Cl may be substituted by OH. Energy-dispersive mapping under the scanning electron microscope demonstrated that the majority of these deposits are present in the outer cell wall of the epidermis (the outermost layer of root cells). The phosphate composition of these grains contrasts with the phytate (C6H18O24P612−) composition of Zn-P deposits observed in similar electron microscopy studies. The physiological role of heavy metal P deposits is unclear. Heavy metal P precipitates may form actively as a tolerance mechanism to heavy metals or passively, sequestering P in a metabolically inactive form.

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On Future Directions in Pathology

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053991 ◽

1982 ◽

Vol 40 ◽

pp. 274-277

Author(s):

Benjamin F. Trump ◽

Irene K. Berezesky ◽

Raymond T. Jones

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Clinical Pathology ◽

Future Directions ◽

Diagnostic Pathology ◽

The Past ◽

Transmission Electron ◽

Organ Systems ◽

The Many

The role of electron microscopy and associated techniques is assured in diagnostic pathology. At the present time, most of the progress has been made on tissues examined by transmission electron microscopy (TEM) and correlated with light microscopy (LM) and by cytochemistry using both plastic and paraffin-embedded materials. As mentioned elsewhere in this symposium, this has revolutionized many fields of pathology including diagnostic, anatomic and clinical pathology. It began with the kidney; however, it has now been extended to most other organ systems and to tumor diagnosis in general. The results of the past few years tend to indicate the future directions and needs of this expanding field. Now, in addition to routine EM, pathologists have access to the many newly developed methods and instruments mentioned below which should aid considerably not only in diagnostic pathology but in investigative pathology as well.

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Transmission Electron Microscopy studies of texture of Cr underlayer of magnetic recording hard disk

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087215 ◽

1991 ◽

Vol 49 ◽

pp. 580-581

Author(s):

L. Tang ◽

G. Thomas ◽

M. R. Khan ◽

S. L. Duan

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Magnetic Recording ◽

Magnetic Thin Films ◽

Magnetic Films ◽

Substrate Bias ◽

Epitaxial Relationship ◽

Transmission Electron

Cr thin films are often used as underlayers for Co alloy magnetic thin films, such as Co1, CoNi2, and CoNiCr3, for high density longitudinal magnetic recording. It is belived that the role of the Cr underlayer is to control the growth and texture of the Co alloy magnetic thin films, and, then, to increase the in plane coercivity of the films. Although many epitaxial relationship between the Cr underlayer and the magnetic films, such as ﹛1010﹜Co/ {110﹜Cr4, ﹛2110﹜Co/ ﹛001﹜Cr5, ﹛0002﹜Co/﹛110﹜Cr6, have been suggested and appear to be related to the Cr thickness, the texture of the Cr underlayer itself is still not understood very well. In this study, the texture of a 2000 Å thick Cr underlayer on Nip/Al substrate for thin films of (Co75Ni25)1-xTix dc-sputtered with - 200 V substrate bias is investigated by electron microscopy.

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Transmission Electron Microscopy of Evaporated Perylene Thin Films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135289 ◽

1990 ◽

Vol 48 (2) ◽

pp. 336-337

Author(s):

C. Ewins ◽

J.R. Fryer

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Molecular Electronics ◽

High Vacuum ◽

Amorphous Layer ◽

Electric Heater ◽

Transmission Electron ◽

Polycyclic Aromatic

The preparation of thin films of organic molecules is currently receiving much attention because of the need to produce good quality thin films for molecular electronics. We have produced thin films of the polycyclic aromatic, perylene C10H12 by evaporation under high vacuum onto a potassium chloride (KCl) substrate. The role of substrate temperature in determining the morphology and crystallography of the films was then investigated by transmission electron microscopy (TEM).The substrate studied was the (001) face of a freshly cleaved crystal of KCl. The temperature of the KCl was controlled by an electric heater or a cold finger. The KCl was heated to 200°C under a vacuum of 10-6 torr and allowed to cool to the desired temperature. The perylene was then evaporated over a period of one minute from a molybdenum boat at a distance of 10cm from the KCl. The perylene thin film was then backed with an amorphous layer of carbon and floated onto copper microscope grids.

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Fine structure and possible functions of the hermaphrodite duct of some pulmonate snails (Mollusca: Gastropoda)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100157887 ◽

1990 ◽

Vol 48 (3) ◽

pp. 68-69

Author(s):

Alan N. Hodgson

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Fine Structure ◽

Seminal Vesicle ◽

Reproductive Biology ◽

Light Microscope ◽

Light Microscope Level ◽

Transmission Electron ◽

Standard Techniques

The hermaphrodite duct of pulmonate snails connects the ovotestis to the fertilization pouch. The duct is typically divided into three zones; aproximal duct which leaves the ovotestis, the middle duct (seminal vesicle) and the distal ovotestis duct. The seminal vesicle forms the major portion of the duct and is thought to store sperm prior to copulation. In addition the duct may also play a role in sperm maturation and degredation. Although the structure of the seminal vesicle has been described for a number of snails at the light microscope level there appear to be only two descriptions of the ultrastructure of this tissue. Clearly if the role of the hermaphrodite duct in the reproductive biology of pulmonatesis to be understood, knowledge of its fine structure is required.Hermaphrodite ducts, both containing and lacking sperm, of species of the terrestrial pulmonate genera Sphincterochila, Levantina, and Helix and the marine pulmonate genus Siphonaria were prepared for transmission electron microscopy by standard techniques.

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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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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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The Role of Microscopy in Preclinical Safety Assessment

Microscopy and Microanalysis ◽

10.1017/s143192760003748x ◽

2000 ◽

Vol 6 (S2) ◽

pp. 998-999

Author(s):

Barbara J. Dovey-Hartman

Keyword(s):

Electron Microscopy ◽

Vital Role ◽

Pathology Report ◽

Clinical Phase ◽

Transmission Electron ◽

New Chemical Entities ◽

Regulatory Submissions ◽

Hematoxylin And Eosin ◽

Preclinical Safety

Microscopy plays a vital role in assessing the safety of New Chemical Entities (NCE) in the pre-clinical phase of drug development. Light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) are used at the Schering-Plough Research Institute (SPRI) for evaluation of NCE. To support regulatory submissions, NCE are routinely tested in rodents in short-term studies such as one-month toxicity studies, and in longterm studies such as oncogenicity studies that may last 24 months. At the completion of a study, the animals are necropsied and the required tissues collected and stored in fixative. The tissues for LM are processed to slides and stained with Hematoxylin and Eosin (H&E). The information derived from the examination of these tissues by LM becomes an essential part of the pathology report. The LM examination of these tissues usually yields the information needed to either progress a NCE or otherwise deter or halt development.

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Strengthening Evaluation in a Composite Mg-RE Alloy Using TEM

Materials Science Forum ◽

10.4028/www.scientific.net/msf.678.75 ◽

2011 ◽

Vol 678 ◽

pp. 75-84 ◽

Cited By ~ 2

Author(s):

Marcello Cabibbo

Keyword(s):

Electron Microscopy ◽

Metal Matrix ◽

Room Temperature ◽

Strengthening Mechanism ◽

Composite Alloy ◽

Specific Strength ◽

High Specific Strength ◽

Transmission Electron ◽

Sic Ceramic

Magnesium alloys containing rare earth elements are known to have high specific strength and corrosion resistance. The addition of SiC ceramic particles makes the metal matrix composite stronger with better wear and creep resistance and a still good machinability. The role of the reinforcement particles to the enhanced strength can be quantitatively evaluated using transmission electron microscopy (TEM). This paper presents a quantitative strengthening evaluation in a SiC Mg-RE composite alloy. The different contributions were determined by TEM inspections. The microstructure strengthening mechanism was studied after room temperature compression specimens. The way of combining the different contributions and the comparison to the measured yield stress, is also discussed and justified.

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Synthesis and Characterizations of Nanocubes, Monodispersed Nanocrystals and Nanospheres of Au

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.2163 ◽

2007 ◽

Vol 353-358 ◽

pp. 2163-2166

Author(s):

Ming Yang ◽

Guo Qing Zhou ◽

Jiang Guo Zhao ◽

Zhan Jun Li

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Powder Diffraction ◽

Visible Absorption ◽

X Ray ◽

Transmission Electron ◽

Uv Visible ◽

Scherrer Formula ◽

Visible Absorption Spectroscopy

Nanocubes, monodispersed nanocrystals and nanospheres of Au have been prepared by a simple reaction between HAuCl4·4H2O, NaOH and NH2OH·HCl in the presence of gelatin. The role of gelatin and the affection of pH in producing the nanoparticles of Au were discussed. The products were characterized by X-ray powder diffraction, transmission electron microscopy, and UV-visible absorption spectroscopy. The sizes of the monodispersed nanocrystals of Au were estimated by Debye-Scherrer formula according to XRD spectrum.

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