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Powder synthesis is crucial for achieving the densification and facilitating widespread applications of high entropy carbide (HEC). Specifically, the production of fine particle‐size powders is essential to enhance the densification of HECs. Consequently, this paper proposes the molten salt method for synthesizing HEC powders. The synthesis process successfully yielded (Ta Nb Ti V) C powders with a particle size of only 0.44 µm at 1400°C, exhibiting a uniform distribution of each element. Subsequent densification of (Ta Nb Ti V) C within the 1700–1900°C temperature range was carried out using spark plasma sintering. It was observed that as the densification temperature increased, the densification and mechanical properties of HEC significantly improved. This study presents innovative ideas for the preparation of HEC at lower temperatures. [ABSTRACT FROM AUTHOR]

Borosilicate glass has been extensively studied due to its unique properties of solidifying high‐level radioactive waste (HLW). However, the responses of borosilicate glass under γ irradiation are not fully understood. In this work, NBS9 and NBS10 glass were irradiated by γ‐rays at absorbed doses of 8 kGy and 800 kGy, respectively. Scanning electronic microscopy, energy dispersive X‐ray, and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) were used to observe the surface morphology and elemental distributions. The results show that the borosilicate glass remains stable until the absorbed dose was up to 800 kGy. At 800 kGy, the samples precipitate particles composed of Na and O on the surface. Na and B near the surface are significantly reduced under γ‐rays irradiation. The results indicate that the effects of γ irradiation on glass vitrification are obvious with certain accumulated doses. The changes of glass structures and elemental distributions by γ‐ray irradiation are also dependent on glass compositions. [ABSTRACT FROM AUTHOR]

There is an urgent demand for multifunctional insulation materials with neutron shielding ability that can be particularly used in the nuclear energy system. GdBO3 ceramics are one of the candidates for such materials. In this study, GdBO3 ceramics were successfully synthesized using a simple solid‐phase method. The effect of boric acid content on the micro and macro properties of GdBO3 ceramics was explored. The experimental results indicate that the thermal conductivity of the resulting GdBO3 ceramics ranged from.12 to.68 W/(m⋅K), and lower thermal conductivity was achieved with smaller pore size and higher apparent porosity of the sintered product. Moreover, the mechanical properties of the samples in multiple temperature ranges can be improved by increasing boric acid content. Finally, neutron shielding permeability study, performed on the samples in different thicknesses, reveal that GdBO3 ceramics possessed excellent neutron shielding performance (NSP). The obtained results manifest that GdBO3 ceramics with outstanding heat insulation and NSP have a potential application in a nuclear reactor. [ABSTRACT FROM AUTHOR]

Fast neutron detection is significant for neutron imaging and flux monitoring but cannot be directly achieved by inorganic semiconductors. The traditional detection is mainly mediated by an organic scintillator and a coupled photodetector, resulting in signal losses. Here, a direct detection method for fast neutrons is demonstrated based on organic semiconducting single crystals (OSSCs) detectors. Methyl 4‐hydroxybenzoate (4MHB, C6H5O‐COOCH3) and 4‐hydroxycyanobenzene (4HCB, C6H5O‐CN). The organic semiconductor acts as a fast neutron sensitive material due to its high hydrogen density, simultaneously as a semiconductor that generates the electric signal. The detectors based on 4MHB crystals can quantitatively measure the dose and energy of the fast neutron flux with a response time of 0.5 µs and detection efficiency of 78.5% cm−3. Effects of functional groups on fast neutron detection performances are also investigated as a guideline to synthesis new molecules for this purpose. Furthermore, neutron radiation effects on these detectors are investigated. Hydrogen‐related point defects are generated by fast neutrons, but device performances remain robust after irradiation of 1013 n cm−2 fast neutrons. This study demonstrates that OSSCs show great potential as direct fast neutron detectors and particularly have highly‐localized and tissue‐equivalent properties that benefit neutron imaging and cancer therapy applications. [ABSTRACT FROM AUTHOR]

Environment‐oriented low‐cost Al2O3 reticulated porous ceramics with hierarchical pore structure were fabricated by the polymer sponge replica method combined with vacuum infiltration methods, using Al2O3 powders and SiC solid waste (SCSW) as raw material and a pore‐forming agent. The effects of SCSW addition amount on mechanical properties, microstructure and pore size of Ceramics were investigated. The results showed that the thermal shock resistance of specimens increased gradually with addition of SCSW, however, the median pore diameter increased firstly and then decreased, due to the generation of mullite and liquid phase. After calcination, the residual stress was generated within the coating layer because of the difference in the thermal expansion coefficients of ceramic matrix and coating layer, which could improve the properties of Ceramics by deflecting and bifurcating crack growth path. The results showed that the best dosage of SCSW was 30 wt%. [ABSTRACT FROM AUTHOR]

Aluminum borate ceramics (ABCs) with a skeleton structure of rod‐like crystals were established via a solid‐state reaction synthesis. The influence of heat treatment systems on the phase composition and microstructural evolution of an anisotropic grain were firstly studied. Next, the impact of boric acid content on the activation energy of reaction, microstructure, mechanical properties, and neutron shielding capability were investigated. The results demonstrate that orthorhombic Al18B4O33 formed between 900°C and 1000°C which was the stable phase during heating treatment. In addition, increasing the boric acid content was favorable for reducing the activation energy of forming aluminum borate, resulting in increased in situ formation and growth of aluminum borate whiskers in fired samples. Next, mircropores could be generated by the decomposition of boric acid at high temperatures, which had a considerable influence on the physical properties of the sample. Furthermore, the Monte Carlo particle transport program simulation and neutron shielding experiments showed that the prepared ABCs could shield neutron effectively manifested as possessing a high neutron absorption cross‐section in the case of porous materials. Moreover, ABCs have potential application value as thermal insulation material in the nuclear energy field. [ABSTRACT FROM AUTHOR]