Self-propagating high-temperature synthesis of CeO2 incorporated zirconolite-rich waste forms and the aqueous durability

2015 ◽  
Vol 35 (11) ◽  
pp. 3085-3093 ◽  
Author(s):  
Kuibao Zhang ◽  
Guanjun Wen ◽  
Haibin Zhang ◽  
Yuancheng Teng
Keyword(s):  
High Temperature ◽  
Temperature Synthesis ◽  
Waste Forms ◽  
High Temperature Synthesis

scholarly journals Rapid Immobilization of Simulated Radioactive Soil Waste Using Self-Propagating Synthesized Gd2Ti2O7 Pyrochlore Matrix

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1163 ◽  
Author(s):  
Jiali Xue ◽  
Kuibao Zhang ◽  
Zongsheng He ◽  
Wenwen Zhao ◽  
Weiwei Li ◽  
...  
Keyword(s):  
Phase Composition ◽  
High Temperature ◽  
Contaminated Soil ◽  
Chemical Durability ◽  
Leaching Rate ◽  
Rapid Synthesis ◽  
Temperature Synthesis ◽  
Main Work ◽  
Waste Forms ◽  
High Temperature Synthesis

A rapid and effective method is necessary in the disposal of severely radioactive contaminated soil waste. Simulated Ce-bearing radioactive soil waste was immobilized by self-propagating high-temperature synthesis (SHS) within 5 min in this study. The main work includes the rapid synthesis of soil waste forms, the analysis of phase composition, microstructure and chemical durability. These results show that the simulated nuclide Ce was successfully immobilized into the pyrochlore-rich waste matrice, whose main phases are SiO2, pyrochlore (Gd2Ti2O7) and Cu. The normalized leaching rates of Si and Na on the 42nd day are 1.86 × 10−3 and 1.63 × 10−2 g·m−2·d−1, respectively. And the normalized leaching rate of Ce also remains at low level (10−5–10−6 g·m−2·d−1) within 42 days.

Self-Propagating High-Temperature Synthesis of Simulated 90SrO-Contained Radioactive Graphite in N2 Atmosphere

2014 ◽  
Vol 525 ◽  
pp. 45-52 ◽  
Author(s):  
Xi Rui Lu ◽  
Si Jin Su ◽  
Meng Jun Chen
Keyword(s):  
Titanium Dioxide ◽  
High Temperature ◽  
Titanium Carbide ◽  
Exothermic Reaction ◽  
The Self ◽  
Cubic Phase ◽  
Temperature Synthesis ◽  
Radioactive Graphite ◽  
Waste Forms ◽  
High Temperature Synthesis

In order to evaluate the performance of the self-propagating high-temperature synthesis (SHS) to treat 90SrO-contained radioactive graphite in N2 atmosphere, waste forms were prepared with the self-developed SHS reactor according to the waste forms formulation designed with a solid-soluted content of 010 wt% (calibrated in mass, hereinafter the same). The waste forms were made with the exothermic reaction (3C + 4Al + 3TiO2 = 2Al2O3 + 3TiC + Q), where, 88SrO (a stable Sr isotope)-containing 88SrO was used to simulate 90SrO. And the raw materials for the waste forms were the powdery materials of graphite (C), aluminum (Al) and titanium dioxide (TiO2). Then, X-ray diffractometer (XRD) and scanning electron microscope (SEM) were used to test and analyze the phase composition and morphology of the prepared waste forms. According to the results in dealing with the treatment with the given exothermic reaction of the 90SrOcontaining radioactive graphite in N2 atmosphere, the SrO solid solubility could be up to 8 wt%. Besides, with a SrO content of 0~2 wt%, the major composition of the waste forms was including: alumina (Al2O3) in diamond scheme, titanium carbide (TiC) in cubic phase, graphite (C), anatase titanium dioxide (TiO2) and aluminum nitride (AlN) in cubic phase. Comparatively, with a SrO content of 3~8 wt%%, the major composition of the waste forms was including: alumina (Al2O3) in diamond scheme, titanium carbide (TiC) in cubic phase, graphite (C), anatase titanium dioxide (TiO2), aluminum nitride (AlN) in cubic phase and rhomboid aluminum titanate (Al2TiO5). Furthermore, diffractive peaks of unidentified phase occurred at 2θ = 7.7°, 15.6°, 19.8° and 24.1° position, whose intensities were increased with the increasing additional SrO content. The grain sizes of the prepared waste forms are mainly within 515μm, majorly exist in pieces.

Hardening of metal surface via self-propagating high-temperature synthesis in thin films

2007 ◽  
Vol 43 (4) ◽  
pp. 239-242
Author(s):  
S. Kh. Suleimanov ◽  
O. A. Dudko ◽  
V. G. Dyskin ◽  
Z. S. Settarova ◽  
M. U. Dzhanklych
Keyword(s):  
Thin Films ◽  
High Temperature ◽  
Metal Surface ◽  
Temperature Synthesis ◽  
High Temperature Synthesis

Effect of Additives on the Characteristics of Amorphous Nano Boron Powder Fabricated by Self-Propagating High Temperature Synthesis

2015 ◽  
Vol 25 (12) ◽  
pp. 659-665
Author(s):  
Sin Hyong Joo ◽  
Hayk H. Nersisyan ◽  
Tae Hyuk Lee ◽  
Young Hee Cho ◽  
Hong Moule Kim ◽  
...  
Keyword(s):  
High Temperature ◽  
Temperature Synthesis ◽  
Boron Powder ◽  
Effect Of Additives ◽  
High Temperature Synthesis

scholarly journals High-Temperature Synthesis of Metal–Matrix Composites (Ni-Ti)-TiB2

2021 ◽  
Vol 11 (5) ◽  
pp. 2426
Author(s):  
Vladimir Promakhov ◽  
Alexey Matveev ◽  
Nikita Schulz ◽  
Mikhail Grigoriev ◽  
Andrey Olisov ◽  
...  
Keyword(s):  
High Temperature ◽  
Composite Materials ◽  
Metal Matrix Composite ◽  
Matrix Composite ◽  
Metal Matrix ◽  
Average Particle Size ◽  
Synthesis Process ◽  
Average Particle ◽  
Temperature Synthesis ◽  
High Temperature Synthesis

Currently, metal–matrix composite materials are some of the most promising types of materials, and they combine the advantages of a metal matrix and reinforcing particles/fibres. Within the framework of this article, the high-temperature synthesis of metal–matrix composite materials based on the (Ni-Ti)-TiB2 system was studied. The selected approaches make it possible to obtain composite materials of various compositions without contamination and with a high degree of energy efficiency during production processes. Combustion processes in the samples of a 63.5 wt.% NiB + 36.5 wt.% Ti mixture and the phase composition and structure of the synthesis products were researched. It has been established that the synthesis process in the samples proceeds via the spin combustion mechanism. It has been shown that self-propagating high-temperature synthesis (SHS) powder particles have a composite structure and consist of a Ni-Ti matrix and TiB2 reinforcement inclusions that are uniformly distributed inside it. The inclusion size lies in the range between 0.1 and 4 µm, and the average particle size is 0.57 µm. The obtained metal-matrix composite materials can be used in additive manufacturing technologies as ligatures for heat-resistant alloys, as well as for the synthesis of composites using traditional methods of powder metallurgy.

scholarly journals Dopants Modulate Crystal Growth in Molten Salts Enabled by Surface Energy Tuning

2021 ◽  
Author(s):  
Xiaoqiao Li ◽  
Linming Zhou ◽  
Han Wang ◽  
Dechao Meng ◽  
Guannan Qian ◽  
...  
Keyword(s):  
Crystal Growth ◽  
High Temperature ◽  
Surface Energy ◽  
Molten Salts ◽  
Rational Approach ◽  
Temperature Synthesis ◽  
Crystalline Materials ◽  
Size Dependent ◽  
High Temperature Synthesis ◽  
Energy Tuning

Crystalline materials are routinely produced via high-temperature synthesis and show size-dependent properties; however, a rational approach to regulating their crystal growth has not been established. Here we show that dopants...

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