Mechanism of Heavy Element Retention in Hydrated Layers Formed on Leached Silicate Glasses

1988 ◽  
Vol 127 ◽  
Author(s):  
J.-C. Petit ◽  
J.-C. Dran ◽  
L. Trotignon ◽  
J.-M. Casabonne ◽  
A. Paccagnella ◽  
...  
Keyword(s):  
Rutherford Backscattering Spectrometry ◽  
Selective Dissolution ◽  
Silicate Glasses ◽  
Heavy Elements ◽  
Nuclear Reaction Analysis ◽  
Aqueous Corrosion ◽  
Silica Surfaces ◽  
Dissolution Behaviour ◽  
The Relationship

ABSTRACTWe have investigated the relationship between hydrated layer formation during aqueous corrosion of silicates and retention of heavy elements (Fe, REE, actinides). Our approach is based on the comparison of the dissolution behaviour of silicate glasses, silicate minerals implanted with increasing doses of lead ions (1×E+12 to 1×E+15 ions/cm2), sorption experiments on silica surfaces and direct precipitation of hydrosilicates. The characterization of reacted surfaces was performed by combining Rutherford backscattering spectrometry (RBS) for profiling heavy elements with Resonant Nuclear Reaction Analysis (RNRA) for hydrogen profilimetry. The accumulation of these elements does not necessarily imply a selective dissolution and can be explained by the “precipitation” of hydroxides or hydrosilicates.

Characterization of SiC Thin Film Obtained by Magnetron Reactive Sputtering: IBA, IR and Raman Studies

2005 ◽  
Vol 483-485 ◽  
pp. 287-290
Author(s):  
H. Colder ◽  
M. Morales ◽  
Richard Rizk ◽  
I. Vickridge
Keyword(s):  
Nuclear Reaction ◽  
Hydrogen Content ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Nuclear Reaction Analysis ◽  
Elastic Recoil ◽  
Crystalline Fraction ◽  
Elastic Recoil Detection ◽  
Beam Analysis

Co-sputtering of silicon and carbon in a hydrogenated plasma (20%Ar-80%H2) at temperatures, Ts, varying from 200°C to 600°C has been used to grow SiC thin films. We report on the influence of Ts on the crystallization, the ratio Si/C and the hydrogen content of the grown films. Film composition is determined by ion beam analysis via Rutherford backscattering spectrometry, nuclear reaction analysis via the 12C(d,p0)13C nuclear reaction and elastic recoil detection analysi(ERDA) for hydrogen content. Infrared absorption (IR) has been used to determine the crystalline fraction of the films and the concentration of the hydrogen bonded to Si or to C. Complementary to IR, bonding configuration has been also characterized by Raman spectroscopy. As Ts is increased, the crystalline fraction increases and the hydrogen content decreases, as observed by both ERDA and IR. It also appears that some films contain a few Si excess, probably located at the nanograin boundaries.

Ion Beam Techniques for Low K Materials Characterization

1998 ◽  
Vol 511 ◽  
Author(s):  
H. Bakhru ◽  
A. Kumar ◽  
T. Kaplan ◽  
M. Delarosa ◽  
J. Fortin ◽  
...  
Keyword(s):  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Nuclear Reaction Analysis ◽  
Ion Beam Analysis ◽  
Analytical Technique ◽  
Analysis Techniques ◽  
Teflon Af ◽  
Beam Analysis ◽  
Low K

ABSTRACTIon beam analysis techniques have become very useful for characterization of low k materials. Studies on several ion beam analysis techniques will be discussed. Rutherford Backscattering Spectrometry (RBS) provides a very powerful analytical technique for the thickness and porosity measurements on porous Si0 2 films. Nuclear Reaction Analysis (NRA) techniques for hydrogen and fluorine profiling are very useful to characterize fluorinated polymer and fluorinated oxide films. Examples of low k materials including Si02:F, Parylene-AF and Teflon-AF will be discussed. Fluorine diffusion in to metals and various interface effects between metal and low k materials will be presented.

Preparation and characterization of oxide film electrodes

1997 ◽  
Vol 75 (11) ◽  
pp. 1759-1765 ◽  
Author(s):  
A. De Battisti ◽  
G. Lodi ◽  
L. Nanni ◽  
G. Battaglin ◽  
A. Benedetti
Keyword(s):  
Oxide Film ◽  
Nuclear Reaction ◽  
Mixed Oxide ◽  
Preparation Method ◽  
Rutherford Backscattering Spectrometry ◽  
Oxide Films ◽  
Rutherford Backscattering ◽  
Model Systems ◽  
Nuclear Reaction Analysis

In this paper are presented data on the preparation and characterization of different oxide electrodes. RuO2–TiO2, IrO2–TiO2, and SnO2–Sb2O5 mixed-oxide films have been taken as model systems. For the first, the traditional preparation method based on the pyrolysis of precursor salt deposits was adopted. For the SnO2-based films, the spray pyrolysis preparation has been used. The characterization of RuO2–TiO2 films confirms the existence of a solid solution between the two component oxides over a wide composition range. Rutherford backscattering spectrometry confirms the occurrence of segregation of titanium oxide species in the outermost part of the films. Nuclear reaction analysis indicates that large amounts of carbon and hydrogen impurities are trapped in the oxide films. SnO2-based films were found to be less porous and chemically more simple. The differences between the two systems have been discussed in terms of the preparation method and the differences in chemical properties of the precursors. Keywords: oxide film electrodes, mixed-oxide films, Rutherford backscattering spectrometry, nuclear reaction analysis.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Microstructural Characterization of Au-Ge-Ni based ohmic contacts to GaAs/AlGaAs modfet device

1987 ◽  
Vol 45 ◽  
pp. 326-327
Author(s):  
A.K. Rai ◽  
A.K. Petford-Long ◽  
A. Ezis ◽  
D.W. Langer
Keyword(s):  
Contact Resistance ◽  
Ohmic Contact ◽  
Ohmic Contacts ◽  
Microstructural Characterization ◽  
Almost Everywhere ◽  
Spacer Layer ◽  
Good Contact ◽  
The Relationship ◽  
Lower Contact

Considerable amount of work has been done in studying the relationship between the contact resistance and the microstructure of the Au-Ge-Ni based ohmic contacts to n-GaAs. It has been found that the lower contact resistivity is due to the presence of Ge rich and Au free regions (good contact area) in contact with GaAs. Thus in order to obtain an ohmic contact with lower contact resistance one should obtain a uniformly alloyed region of good contact areas almost everywhere. This can possibly be accomplished by utilizing various alloying schemes. In this work microstructural characterization, employing TEM techniques, of the sequentially deposited Au-Ge-Ni based ohmic contact to the MODFET device is presented.The substrate used in the present work consists of 1 μm thick buffer layer of GaAs grown on a semi-insulating GaAs substrate followed by a 25 Å spacer layer of undoped AlGaAs.

Characterization of Auditory Disability and Its Relation to the Resilience

2018 ◽  
Vol 5 (2) ◽  
pp. 15
Author(s):  
Bibian Bibeca Bumbila García ◽  
Hernán Andrés Cedeño Cedeño ◽  
Tatiana Moreira Chica ◽  
Yaritza Rossana Parrales Ríos
Keyword(s):  
Social Integration ◽  
Conceptual Analysis ◽  
Disabled People ◽  
Disabled Students ◽  
Hearing Disability ◽  
Technical University ◽  
The Relationship ◽  
Made In

The objective of the work is to establish the characterization of the auditory disability and its relationship with resilience at the Technical University of Manabí. The article shows a conceptual analysis related to the inclusion and social integration of disabled students. Based on the fact that the person with disabilities grows and develops in the same way as that of people without disabilities and what usually happens is that disabled people are rejected and discriminated against based on a prefabricated and erroneous conceptualization of these people. The results associated with the application of the SV-RES test prepared by the researchers are shown (Saavedra & Villalta, 2008b). Characterization of the auditory deficit is made in the students, and the limitations that derive from it are pointed out. We analyze the particularities related to communication with students who have a hearing disability and resilience in this type of student, where some personal highlights that in this sense constitute an example of resilience. Finally, the results related to the study of the relationship between students' hearing disability and the level of resilience dimensions are shown.

The Problem of Divine Hiddenness

2018 ◽  
Author(s):  
Michael C. Rea
Keyword(s):  
Problem Of Evil ◽  
Philosophical Discussion ◽  
Detailed Characterization ◽  
The Past ◽  
Divine Hiddenness ◽  
The Problem Of Evil ◽  
The Relationship

This chapter provides a detailed characterization of the various meanings of the term “divine hiddenness,” carefully and rigorously articulates the version of the problem of divine hiddenness that has dominated contemporary philosophical discussion for the past twenty-five years, and then explains the relationship between that problem and the problem of evil.

scholarly journals Crowdsourcing and open innovation: a systematic literature review, an integrated framework and a research agenda

2021 ◽  
Author(s):  
Livio Cricelli ◽  
Michele Grimaldi ◽  
Silvia Vermicelli
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Open Innovation ◽  
Innovation Management ◽  
Academic Research ◽  
Future Research ◽  
Four Dimensions ◽  
Word Analysis ◽  
The Relationship

AbstractIn recent years, Open Innovation (OI) and crowdsourcing have been very popular topics in the innovation management literature, attracting significant interest and attention, and inspiring a rich production of publications. Although these two topics share common themes and address similar managerial challenges, to the best of our knowledge, there is no systematic literature review that digs deep into the intersection of both fields. To fill in this gap a joint review of crowdsourcing and OI topics is both timely and of interest. Therefore, the main objective of this study is to carry out a comprehensive, systematic, and objective review of academic research to help shed light on the relationship between OI and crowdsourcing. For this purpose, we reviewed the literature published on these two topics between 2008 and 2019, applying two bibliometric techniques, co-citation and co-word analysis. We obtained the following results: (i) we provide a qualitative analysis of the emerging and trending themes, (ii) we discuss a characterization of the intersection between OI and crowdsourcing, identifying four dimensions (strategic, managerial, behavioral, and technological), (iii) we present a schematic reconceptualization of the thematic clusters, proposing an integrated view. We conclude by suggesting promising opportunities for future research.

scholarly journals Characterization of the Relationship between Polysaccharide Intercellular Adhesin and Hemagglutination inStaphylococcus epidermidis

1999 ◽  
Vol 179 (6) ◽  
pp. 1561-1564 ◽  
Author(s):  
Paul D. Fey ◽  
Joseph S. Ulphani ◽  
Friedrich Götz ◽  
Christine Heilmann ◽  
Dietrich Mack ◽  
...  
Keyword(s):  
Polysaccharide Intercellular Adhesin ◽  
The Relationship
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