An in situ Study of the Kinetics of a Solid-Phase Reaction Activated by the Energy of Elastic Stresses Arisen upon the Formation of the Cu/As2Se3 Nanosized Film Structure

2018 ◽  
Vol 44 (11) ◽  
pp. 1002-1004
Author(s):  
V. Ya. Kogai
Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 330
Author(s):  
Hengli Xiang ◽  
Genkuan Ren ◽  
Yanjun Zhong ◽  
Dehua Xu ◽  
Zhiye Zhang ◽  
...  

Fe3O4@C nanoparticles were prepared by an in situ, solid-phase reaction, without any precursor, using FeSO4, FeS2, and PVP K30 as raw materials. The nanoparticles were utilized to decolorize high concentrations methylene blue (MB). The results indicated that the maximum adsorption capacity of the Fe3O4@C nanoparticles was 18.52 mg/g, and that the adsorption process was exothermic. Additionally, by employing H2O2 as the initiator of a Fenton-like reaction, the removal efficiency of 100 mg/L MB reached ~99% with Fe3O4@C nanoparticles, while that of MB was only ~34% using pure Fe3O4 nanoparticles. The mechanism of H2O2 activated on the Fe3O4@C nanoparticles and the possible degradation pathways of MB are discussed. The Fe3O4@C nanoparticles retained high catalytic activity after five usage cycles. This work describes a facile method for producing Fe3O4@C nanoparticles with excellent catalytic reactivity, and therefore, represents a promising approach for the industrial production of Fe3O4@C nanoparticles for the treatment of high concentrations of dyes in wastewater.


2007 ◽  
Vol 124-126 ◽  
pp. 287-290 ◽  
Author(s):  
Fei Liu ◽  
Yong Jun He ◽  
Jeung Soo Huh

The nano-CeO2 was synthesized by two-step solid-phase reaction. The image of TEM showed that nano-CeO2 with an average size of about 70 nm. The series of polyaniline/nano-CeO2 composites with different PANi: CeO2 ratios were prepared by in-situ polymerization in the presence of hydrochloric acid (HCl) as dopant by adding nano-CeO2 into the polymerization reaction mixture of aniline. The composites obtained were characterized by FT-IR and UV-vis spectroscopy analysis. The FT-IR spectra of nanocomposites indicate different blue-shifts, attributed to C–N stretching mode for benzenoid unit. The UV-vis spectra of nanocomposites display einstein-shifts compared with PANi at 620nm. The conductivity properties of the composites are also changed compare to the pure PANi. These results suggest that the interactions between the polymer matrix and nanoparticles take place in polyaniline/nano- CeO2 composites.


2020 ◽  
Author(s):  
Eszter Badenszki ◽  
J. Stephen Daly ◽  
Martin J. Whitehouse ◽  
Brian G. J. Upton

<p>EN-101, a rare albitite [Pl +Fe-Ti oxide +Ap +Zrn] xenolith from Elie Ness, Scottish Midland Valley, is hosted by a c. 290 Ma old alkali basaltic diatreme [1, 2].  EN-101 is considered to belong to the Scottish “anorthoclasite suite” comprising xenoliths and megacrysts of various compositions which are interpreted as samples from the upper mantle – lower crust where they form (syenitic) vein or dyke-like bodies e.g., [3, 4, 5]. The “anorthoclasite suite” has been found in all Scottish terranes suggesting that the presumed dyke system must be extensive.</p><p>Xenoliths of the “anorthoclasite suite” primarily consist of Na-rich and Ca-poor feldspar megacrysts, with generally high Na/K ratios [3] that are typically accompanied by accessory zircon, apatite, biotite, magnetite and Fe-rich pyroxene whereas garnet and corundum with Nb-rich oxides are only occasionally present [3, 4, 5]. Upton et al. [4, 5] argued that the parental melt of the “anorthoclasite suite” formed though small–fraction melting of metasomatized mantle and subsequent melt–solid phase reaction was also involved.  Upton et al. [5] proposed that crystallization of the anorthoclasite suite samples occurred shortly prior to- or contemporaneously with their entrainment. However so far no in-situ dating has been carried out on these samples.</p><p>Early attempts to date the anorthoclasite suite using zircon and feldspar megacrysts from Elie Ness suggested at least a two-stage formation mechanism, where zircon megacrysts yielded a U-Pb age of c. 318 Ma, while euhedral feldspar xenocrysts are significantly younger and roughly coeval with the host volcanism yielding a K-Ar whole-rock age of c. 294 Ma [6].  In this study we present the first in situ U-Pb dating of zircon, which yielded a concordia age of 328 ± 2 Ma (MSWD=0.19; n=12) for EN-101. Zircons εHf<sub>328</sub> values range from +5.2 to +7.5 consistent with a mildly depleted source refreshed by metasomatism. These results may indicate that the proposed extensive syenitic veining within the Scottish upper mantle not only has a complex source [5], but is possibly the result of repeated episodes of magma intrusion.</p><p>References:</p><ol><li>Gernon, T.M. et al. 2013 Bulletin of Volcanology. 75:1-20.</li> <li>Gernon, T.M. et al. 2016 Lithos. 264:70-85.</li> <li>Aspen, P. et al. 1990 European Journal of Mineralogy 2:503-17.</li> <li>Upton, B.G.J. et al. 1990 Journal of Petrology.40:935-56.</li> <li>Upton, B.G.J. et al. 2009 Mineral Mag. 73:943-56.</li> <li>Macintyre, R.M. et al. 1981 Transactions of the Royal Society of Edinburgh: Earth Sciences. 72:1-7.</li> </ol>


2018 ◽  
Vol 60 (7) ◽  
pp. 1397
Author(s):  
Р.Р. Алтунин ◽  
Е.Т. Моисеенко ◽  
С.М. Жарков

AbstractA sequence of phases forming during the solid-phase reaction in Al/Pt bilayer thin films has been investigated by in situ electron diffraction. It is shown that the amorphous PtAl_2 phase forms first during the solid-phase reaction initiated by heating. Upon further heating, PtAl_2, Pt_2Al_3, PtAl, and Pt_3Al crystalline phases sequentially form, which is qualitatively consistent with an effective formation heat model. The content of phases forming during the reaction has been quantitatively analyzed and the structural phase transformations have been examined.


2008 ◽  
Vol 53 (4) ◽  
pp. 495-498 ◽  
Author(s):  
A. S. Vanetsev ◽  
A. E. Baranchikov ◽  
Yu. D. Tret’yakov

1998 ◽  
Vol 4 (S2) ◽  
pp. 634-635
Author(s):  
J.K. Farrer ◽  
D.A. Caldwell ◽  
C.J. Palmstrom ◽  
C.B. Carter

A transmission electron microscopy (TEM) analysis on the regrowth of GaAs by a two-stage reaction between a metal layer (M) and a GaAs substrate is presented. The first stage of the regrowth process is the consumption of GaAs in a low temperature reaction with the metal layer, producing an intermediate phase of (MxGaAs). A second solid-phase reaction, induced by the deposition of Ga or As, results in the decomposition of the intermediate phase and the epitaxial regrowth of a layer of GaAs. The sample growth and reactions were performed in-situ in a molecular beam epitaxy system, using Ni for the metal and As deposition for the second reaction. TEM data confirm the formation of the ternary phase, NixGaAs, and its subsequent decomposition into NiAs and GaAs by reacting with the deposited As. A layer of AlGaAs, 100 nm thick, was grown in all samples as a marker.


2016 ◽  
Vol 697 ◽  
pp. 510-514 ◽  
Author(s):  
Feng Rui Zhai ◽  
Ke Shan ◽  
Ruo Meng Xu ◽  
Min Lu ◽  
Zhong Zhou Yi ◽  
...  

In the present paper, the ZrB2/h-BN multiphase ceramics were fabricated by SPS (spark plasma sintering) technology at lower sintering temperature using h-BN, ZrO2, AlN and Si as raw materials and B2O3 as a sintering aid. The phase constitution and microstructure of specimens were analyzed by XRD and SEM. Moreover, the effects of different sintering pressures on the densification, microstructure and mechanical properties of ZrB2/h-BN multiphase ceramics were also systematically investigated. The results show that the ZrB2 was obtained through solid phase reaction at different sintering pressures, and increasing sintering pressure could accelerate the formation of ZrB2 phase. As the sintering pressure increasing, the fracture strength and toughness of the sintered samples had a similar increasing tendency as the relative density. The better comprehensive properties were obtained at given sintering pressure of 50MPa, and the relative density, fracture strength and toughness reached about 93.4%, 321MPa and 3.3MPa·m1/2, respectively. The SEM analysis shows that the h-BN grains were fine and uniform, and the effect of sintering pressure on grain size was inconspicuous. The distribution of grain is random cross array, and the fracture texture was more obvious with the increase of sintering pressure. The fracture mode of sintered samples remained intergranular fracture mechanism as sintering pressure changed, and the grain refinement, grain pullout and crack deflection helped to increase the mechanical properties.


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