scholarly journals The Role of Composition and Phase upon the Lattice Nitrogen Reactivity of Ternary Molybdenum Nitrides

2021 ◽  
Author(s):  
Angela Daisley ◽  
Lucy Costley-Wood ◽  
Justin S. J. Hargreaves
Keyword(s):  
Molybdenum Nitrides ◽  
Metal Composition

AbstractThe reactivity of the lattice nitrogen in the filled β-Mn structured Co2Mo3N and the η-carbide structured Co3Mo3N and Fe3Mo3N has been investigated under 3:1 H2/Ar at temperatures up to 900 °C. The lattice nitrogen in Co3Mo3N was found to be reactive, as reported previously, whereas Co2Mo3N was shown to be stable up to 800 °C. Upon H2/Ar treatment at 900 °C, the Co2Mo3N, Co3Mo3N and Fe3Mo3N phases decomposed. These results suggest that both metal composition and phase have an influence on the bulk lattice nitrogen reactivity of the ternary nitrides.

scholarly journals Localization of cations by pyroantimonate. I. Influence of fixation on distribution of calcium and sodium. An approach by analytical ion microscopy.

1988 ◽  
Vol 36 (1) ◽  
pp. 49-54 ◽  
Author(s):  
P Mentré ◽  
F Escaig
Keyword(s):  
Skeletal Muscle ◽  
Optical Microscopy ◽  
Large Scale ◽  
Ultrastructural Level ◽  
Metal Composition ◽  
Ion Microscopy ◽  
Potassium Pyroantimonate

A modification of the potassium pyroantimonate (PA) method for localization of calcium and sodium was tested using skeletal muscle of mouse. Massive diffusion of these cations, depending on the method of fixation, was demonstrated by analytical ion microscopy (AIM) images on the optical microscopy level. Rapid penetration of the fixative appeared to be the principal condition that reduced diffusion of Ca2+ and Na+. Paraformaldehyde (2%) appeared more efficient than glutaraldehyde (1%) for preserving metal composition. Addition of 1% phenol strikingly improved the quality of the AIM images. Supersaturated PA (4%) appeared to retain about 10 times more sodium in the tissue than insaturated PA (2%). The role of different buffers is also discussed, particularly collidine, which permitted better preservation of sodium. Fixation with this buffer should be very useful for study by AIM of large-scale distribution of sodium. These results are analyzed at the ultrastructural level in the accompanying report.

scholarly journals Key Role of Precursor Nature in Phase Composition of Supported Molybdenum Carbides and Nitrides

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 415 ◽  
Author(s):  
Zdeněk Tišler ◽  
Romana Velvarská ◽  
Lenka Skuhrovcová ◽  
Lenka Pelíšková ◽  
Uliana Akhmetzyanova
Keyword(s):  
Phase Composition ◽  
Final Phase ◽  
Ammonium Heptamolybdate ◽  
Synthesis Conditions ◽  
Temperature Conditions ◽  
Good Dispersion ◽  
Molybdenum Carbides ◽  
Molybdenum Nitrides ◽  
Different Temperatures

In this work, we studied the effect of molybdenum precursors and the synthesis conditions on the final phase composition of bulk and supported molybdenum carbides and nitrides. Ammonium heptamolybdate, its mixture with hexamethylenetetramine, and their complex were used as the precursors at different temperatures. It was investigated that the synthesis of the target molybdenum nitrides strongly depended on the structure of the precursor and temperature conditions, while the synthesis of carbide samples always led to the target phase composition. Unlike the carbide samples, where the α-Mo2C phase was predominant, the mixture of β-Mo2N, MoO2 with a small amount of metal molybdenum was generally formed during the nitridation. All supported samples showed a very good dispersion of the carbide or nitride phases.

scholarly journals Twofold role of calcined hydrotalcites in the degradation of methyl parathion pesticide

2011 ◽  
Vol 2 ◽  
pp. 99-103 ◽  
Author(s):  
Alvaro Sampieri ◽  
Geolar Fetter ◽  
María Elena Villafuerte-Castrejon ◽  
Adriana Tejeda-Cruz ◽  
Pedro Bosch
Keyword(s):  
Aqueous Solution ◽  
Room Temperature ◽  
Methyl Parathion ◽  
Organophosphate Pesticide ◽  
Anionic Clays ◽  
Rivers And Lakes ◽  
Metal Composition ◽  
By Products ◽  
Basic Strength

Methyl parathion (MP) is a very toxic organophosphate pesticide used as a non-systematic insecticide and acaricide on many corps. As MP and its by-products are highly toxic, they have to be retained to avoid pollution of rivers and lakes. Highly efficient sorbents are hydrotalcites (HTs) (or anionic clays). We have correlated the degradation of an aqueous solution of MP at room temperature, with the basicity of the adsorbing materials. It was found that the metal composition of hydrotalcites determines both the surface electronic properties (basic or acidic) and the sorption capacity. Depending on the basic strength, some calcined hydrotalcites can catalyze the transformation of MP to p-nitrophenol (p-NP) and retain its by-products. Such a process has the advantage of being able to be carried out at room temperature and at the pH of the pesticide solution.

Role of dactinomycin in the improved survival of children with Wilms' tumor

JAMA ◽  
1966 ◽  
Vol 195 (12) ◽  
pp. 1005-1009 ◽  
Author(s):  
D. J. Fernbach
Keyword(s):  
Wilms Tumor

Role of the allergist in diagnosis and management of patients with uveitis

JAMA ◽  
1966 ◽  
Vol 195 (3) ◽  
pp. 167-172 ◽  
Author(s):  
T. E. Van Metre
Keyword(s):  
Diagnosis And Management

The power of norms to sway fused group members

2018 ◽  
Vol 41 ◽  
Author(s):  
Winnifred R. Louis ◽  
Craig McGarty ◽  
Emma F. Thomas ◽  
Catherine E. Amiot ◽  
Fathali M. Moghaddam
Keyword(s):  
Evolutionary Anthropology ◽  
Normative Systems ◽  
Violent Extremism ◽  
Identity Fusion ◽  
Group Members

AbstractWhitehouse adapts insights from evolutionary anthropology to interpret extreme self-sacrifice through the concept of identity fusion. The model neglects the role of normative systems in shaping behaviors, especially in relation to violent extremism. In peaceful groups, increasing fusion will actually decrease extremism. Groups collectively appraise threats and opportunities, actively debate action options, and rarely choose violence toward self or others.

Elaborating the role of reflection and individual differences in the study of folk-economic beliefs

2018 ◽  
Vol 41 ◽  
Author(s):  
Kevin Arceneaux
Keyword(s):  
Decision Making ◽  
Individual Differences ◽  
Cognitive Processes ◽  
Evolutionary History ◽  
Behavioral Responses ◽  
History Of ◽  
Economic Beliefs

AbstractIntuitions guide decision-making, and looking to the evolutionary history of humans illuminates why some behavioral responses are more intuitive than others. Yet a place remains for cognitive processes to second-guess intuitive responses – that is, to be reflective – and individual differences abound in automatic, intuitive processing as well.

The role of affect in feelings of obligation

2020 ◽  
Vol 43 ◽  
Author(s):  
Stefen Beeler-Duden ◽  
Meltem Yucel ◽  
Amrisha Vaish
Keyword(s):  
Positive Emotions ◽  
The Creation ◽  
Sense Of Obligation

Abstract Tomasello offers a compelling account of the emergence of humans’ sense of obligation. We suggest that more needs to be said about the role of affect in the creation of obligations. We also argue that positive emotions such as gratitude evolved to encourage individuals to fulfill cooperative obligations without the negative quality that Tomasello proposes is inherent in obligations.

Refining our understanding of the “elephant in the room”

2020 ◽  
Vol 43 ◽  
Author(s):  
Andrew Whiten
Keyword(s):  
Social Cognition ◽  
Cultural Evolution ◽  
Cognitive Abilities ◽  
Critical Factors ◽  
Technological Culture

Abstract The authors do the field of cultural evolution a service by exploring the role of non-social cognition in human cumulative technological culture, truly neglected in comparison with socio-cognitive abilities frequently assumed to be the primary drivers. Some specifics of their delineation of the critical factors are problematic, however. I highlight recent chimpanzee–human comparative findings that should help refine such analyses.

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