Nuclear Engineering and Technology
·
2023
·
IF 2.7
Linjie Zhao,Mao Yang,Chengjian Xiao,Yu Gong,Guangming Ran,Xiaojun Chen,Jiamao Li,Lei Yue,Chao Chen,Jingwei Hou,Heyi Wang,Xinggui Long,Shuming Peng
Understanding the tritium release and retention behavior of candidate tritium breeder materials is crucial for breeder blanket design. Recently, a melt spraying process was developed to prepare Li 4 SiO 4 pebbles, which were subsequently subjected to the in-pile tritium production and extraction platform in China Mianyang Research Reactor (CMRR) to investigate their in-situ tritium release behavior and irradiation performance. The results demonstrate that HT is the main tritium release form, and adding hydrogen to the purge gas reduces tritium retention while increasing the HT percent in the purge gas. Post-irradiation experiments reveal that the irradiated pebbles darken in color and their grains swell, but the mechanical properties remain largely unchanged. It is concluded that the tritium residence time of Li 4 SiO 4 made by melt spraying method at 467 °C is approximately 23.34 h. High-density Li 4 SiO 4 pebbles exhibit tritium release at relatively low temperatures (＜600 °C) that is mainly controlled by bulk diffusion. The diffusion coefficient at 525 °C and 550 °C is 1.19 × 10 −11 cm 2 /s and 5.34 × 10 −11 cm 2 /s, respectively, with corresponding tritium residence times of 21.3 hours and 4.7 hours.
研究领域:
核工程
·
材料科学
·
辐射物理
✓ 已验证
产品关联
DOI
高影响因子
Nuclear Materials and Energy
·
2023
·
IF 2.6
Xin Chen,Yichao Gong,Kun Kang,Yuefei Wang,Jiarui Li,Zhaokun Li,Tao Wu,Guojun Zhang
Li 2 TiO 3 /Li 4 SiO 4 ceramics have been regarded as promising tritium breeders due to their numerous merits. In this work, chitosan was employed as an effective binder to provide adhesion of Li 2 TiO 3 particles to Li 4 SiO 4 particles, resulting in Li 2 TiO 3 /Li 4 SiO 4 ceramics with improved performance. Chitosan could be removed during the sintering process and had little influence on the phase composition. The resulting Li 2 TiO 3 /Li 4 SiO 4 ceramics had higher density (92.5%T.D.), greater crushing loads (115.2 ± 20.8 N) and superior thermal properties (3.61 W/m∙K) when compared to the samples prepared without chitosan. SEM analyses displayed a dual-scale structure and the inter- and trans -granular fracture mode. Thermal cycling tests revealed that the phase composition was stable but the crushing load fell slightly. The crushing load remained at 92.4 ± 17.1 N after 12 cycles. Overall, chitosan plays an important role in the amelioration of interface combination between Li 4 SiO 4 and Li 2 TiO 3 , and thus significantly improve density, crushing load and thermal conductivity of Li 2 TiO 3 /Li 4 SiO 4 .
研究领域:
材料科学
·
核能工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2023
·
IF 3.1
S. Krat,A. Prishvitsyn,Yu. Gasparyan
A probabilistic and diffusion-based model describing concentrations of multiple hydrogen isotopes simultaneously co-depositing with slowly grown metal layer is given. The conditions modeled are identical to stationary ion implantation into bulk material with infinite fluence. Ratios of different multiple hydrogen isotopes occupying same trapping sites in metal layers co-deposited from plasma are estimated. It is shown that if hydrogen isotopes have different detrapping energies in regards to the same trap (vacancy, dislocation, etc.), only the concentration of the isotope with highest detrapping energy decreases monotonously with deposition temperature. The uncertainty of tritium concentration in co-deposited layer based on the uncertainty in detrapping energy of tritium and deuterium is evaluated; for an 0.01 eV difference, a >10% tritium concentration uncertainty is predicted.
研究领域:
材料科学
·
核能工程
✓ 已验证
DOI
高影响因子
Environmental Chemistry Letters
·
2019
·Vol. 18
·期 2
·475-481
·
IF 4.617
Nivesse A-L.,Thibault de Chanvalon A.,Baglan N.,Montavon G.,Granger G.,Péron O.
Tritium ( 3 H), the radioactive isotope of hydrogen, is a contaminant occurring in most nuclear liquid releases from nuclear industries. The behavior of tritium in the environment is an ongoing societal concern, notably the storage of tritium in organic compounds in waters, soils and sediments. In particular, the fate of tritium depends on the availability of hydrogen for isotopic exchanges in natural organic matter, especially in lignin-like molecules. Therefore, we studied here H exchangeability using natural lignite and leonardite humic matter samples. We compared results from gas–solid isotopic exchanges ( α iso ) with those from widely used methods of functional group characterization by means of deprotonation ( α depro = α carboxyl + α phenol + α alcohol ). Since standard methods for titrating total acidity and determining protonated carboxyl groups are limited by the unconstrained slow deprotonation of humic material, we have modified methods to maximize exchangeable hydrogen reactivity by extending the reaction time in reagent solutions out to 3 weeks, while total OH groups are investigated by the standard acetylation method for alcohol group determination. Results show that more than two times less hydrogen remains available for deprotonation than for isotopic exchanges with an average of α iso = 35.9% versus α depro = 15.5%. This finding reveals the existence of a neglected pool of hydrogen likely to play a key role in processes based on hydrogen exchange, such as metal complexation by natural ligands. Results also show the reliability of the isotopic exchange method for hydrogen speciation in soil-type matrices.
研究领域:
环境科学
·
放射生物学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Yichao Gong,Junjie Li,Lin Liu,Lei Xu,Jie Cui,Guojun Zhang,Tiecheng Lu
Improving the lithium density and performance of lithium-based ceramics is the main direction for the development of advanced tritium breeder. In this work, the previously used polymers or organics were replaced by eutectic LiNO 3 –LiCl in wet process for preparing spherical green body, and then Li 4 SiO 4 pebbles were fabricated through molten salt assisted sintering. The eutectic salt used herein was eco-friendly and had little effect on the Li 4 SiO 4 pebbles. Instead, the incorporation of eutectic salt improved the lithium density and sinterability of Li 4 SiO 4 . The prepared Li 4 SiO 4 pebbles exhibited well-grained microstructure, and the grain size increased with the increasing contents of eutectic salt. Compressive tests showed that the crush load increased more than five times when 20 wt% eutectic salt was added. The proposed method may have great prospects in the preparation of tritium breeding materials.
研究领域:
核科学与技术
·
材料科学
✓ 已验证
DOI
高影响因子
Chemical Engineering and Processing-Process Intensification
·
2020
·
IF 3.731
Xin Gao,Sida Zhao,Haifeng Cong,Peng Yan,Xingang Li,Chengjian Xiao,Hong Li
Water distillation is proved to be an effective method for the recovery of tritium from nuclear power plant drainage. In addition to the geometry and material, the surface wettability of the internals also affects the mass transfer performance of the packings. In this paper, we prepared a superhydrophilic coating on the surface of copper packings by a simple method, to increase the intensity of gas-liquid interface, and thus intensifying the heterogeneous mass transfer process. Scanning electron microscopy, atomic force microscopy, X-ray diffraction and X-ray photoelectron spectroscopy were employed to study the physical and chemical condition changes of the packings surface. Measured by ultraviolet fluorescence imaging technology, the wetted area of the copper wire mesh corrugated packing increased by 58.0 % ∼ 91.2 %. The mass transfer performance for separating H 2 O-HTO mixture with tritium activity of 12.9 MBq/kg is conducted in the total reflux mode distillation column. With varied measured conditions, the height equivalent of theoretical plate (HETP) drops from 3.5 ∼ 5.8 cm to 1.9 ∼ 2.4 cm after the packing surface modification, which indicates that the mass transfer performance has been sufficiently improved.
研究领域:
核化学与化工
·
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·
IF 3.45
Yichao Gong,Junjie Li,Shenghui Yang,Mao Yang,Hao Dang,Yingying Ren,Guojun Zhang,Tiecheng Lu
Investigations on the doping modification of tritium breeding materials have been becoming one of the interesting research areas in the past few years. Recently, preparation method, mechanical and physical properties and tritium release behavior of Li 4+x Si 1-x Al x O 4 solid solution have been studied because of its potential advantages in the field of tritium breeding materials. In this paper, a facile approach was proposed to prepare Li 4+x Si 1-x Al x O 4 pebbles with a relatively small grain. TG/DSC and XRD were conducted to investigate the formation process of Li 4+x Si 1-x Al x O 4 . The results showed the crushing strength and thermal conductivity were obviously improved by introduction of hetero-element Al into Li 4 SiO 4 , and the optimal x value for Li 4+x Si 1-x Al x O 4 was 0.2 from the point of high crushing strength and thermal conductivity. This study will be expected to provide references for fabricating other solid solution tritium breeders.
研究领域:
核能科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Juemin Yan,Nanlin He,Xiaojun Chen,Chengjian Xiao,Lin Jie Zhao,Tao Gao
Lithium orthosilicate (Li 4 SiO 4 ) is an important tritium breeder for the fusion blanket concept. It was selected as the first candidate in China's test blanket model. In this study, in order to improve the thermal conductivity and mechanical properties of Li 4 SiO 4 , titanium was chosen to replace the silicon in it. This is because Ti has large atomic radius and the same charge as that of silicon. The fabrication and characterization of Li 4 Si 1-x Ti x O 4 solid solution was carried out. The Li 4 (Si,Ti)O 4 powders were synthesised via a solid-state reaction, and the pebbles were fabricated using the freeze-drying method. The structure, morphology, thermal conductivity, and mechanical properties of the Li 4 (Si,Ti)O 4 samples were analysed using X-ray diffraction, scanning electron microscopy-energy dispersive spectroscopy, a laser thermal conductivity meter, and a universal testing machine. Moreover, the thermal conductivity of Li 4 SiO 4 improved significantly after Ti doping, and the mechanical properties of the Li 4 (Si,Ti)O 4 pebbles sintered at 1000 °C were significantly better than those of Li 4 SiO 4 .
研究领域:
材料科学
·
核能工程
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 12
·1688
·
IF 4.034
Xiaoyu Hu,Peilong Li,Xin Zhang,Bin Yu,Chao Lv,Ning Zeng,Junhong Luo,Zhi Zhang,Jiangfeng Song,Yong Liu
A high-efficient and low-cost catalyst on hydrogen isotope separation between hydrogen and water is an essential factor in industrial application for heavy water production and water detritiation. In past studies, Pt-based catalysts were developed but not practical for commercial use due to their high cost for vapor phase catalytic exchange (VPCE), while for impregnated nickel catalysts with a lower cost the problems of agglomeration and low Ni utilization existed. Therefore, to solve these problems, in-situ grown Ni-based catalysts (NiAl-LDO) derived from a layered double hydroxide (LDH) precursor were fabricated and first applied in VPCE in this work. Compared with traditional impregnated Ni-based catalysts, NiAl-LDO catalysts own a unique layered structure, homogeneous dispersed metallic phase, higher specific surface area as well as stronger metal-support interactions to prevent active metal from agglomerating. These advantages are beneficial for exposing more active sites to improve dynamic contacts between H2and HDO in a catalyst surface and can bring excellent catalytic activity under a reaction temperature of lower than 400 °C. Additionally, we found that the dissociative chemisorption of HDO and H2occurs not only in Ni (111) but also in NiO species where chemisorbed H(ads), D(ads), OH(ads) and OD(ads) are formed. The results highlight that both of the Ni2+species and Ni0species possess catalytic activities for VPCE process.Keywords:vapor phase catalytic exchange;layered double oxides;Ni catalyst;water detritiation
研究领域:
化学工程
·
核化学与化工
✓ 已验证
产品关联
DOI
PubMed
高影响因子
VACUUM
·
2021
·
IF 3.627
Dong-Guang Liu,Ting-Ting Yang,Yu-Lan Liu,Lai-Ma Luo,Yu-Cheng Wu
Tritium permeation is an essential challenge that should be solved in fusion reactors. In this study, the inner wall SiO 2 coating of the 316L stainless steel pipeline for tritium permeation barrier (TPB) is prepared by slurry-spraying method. The microstructure, phase composition, thermal shock resistance, and hydrogen permeation resistance of the SiO 2 coating are investigated. Results show that the coating is amorphous SiO 2 , and the coating is bonded well to the substrate and the thickness of the coating is about 10–15 μm. After six thermal shock treatments, the SiO 2 coating exhibit good thermal shock resistance stability below 700 °C. Results from the hydrogen penetration test indicate that the hydrogen resistance capability of the SiO 2 coating is 16-fold higher than that of the 316L stainless steel substrate. Hydrogen resistance is also 6-fold more stable than that of 316L stainless steel. These characteristics improve significantly the hydrogen resistance performance of the 316L stainless steel substrate.
研究领域:
材料科学
·
核能工程
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2024
·
IF 13
Guilin Wei,Linsen Zhou,Xianglin Wang,Ru Tang,Kelin Chen,Junhong Luo,Jiangfeng Song,Yan Shi,Ning Liu,Xingwen Feng
The construction, use, and maintenance of tritium-related equipment will inevitably produce tritium-containing radioactive waste gas, and the production of efficient catalysts for tritium removal remains a difficult problem. Herein, silicalite-1 zeolite with entrapped Pt nanoclusters is skillfully post-oxidized at an appropriate temperature, building highly active Pt─O sites on the nanoclusters to achieve efficient oxidation of hydrogen isotopes at low temperatures. The designed Pt─O sites can directly participate in the oxidation reaction of hydrogen isotopes. Compared to the case without Pt─O sites, the presence of these sites significantly reduces the reaction energy barrier to 0.55 eV, enabling the catalyst to achieve a hydrogen conversion rate of 99% at a low temperature of 40 °C. Specifically, the O atoms consumed by the Pt─O sites in the reaction are replaced by O 2 gas and this cycle repeats, which is consistent with the Mars-van Krevelen (M–K) theory. This ensures efficient catalytic oxidation of hydrogen isotopes, and provides an astonishingly high conversion rate of 99% in the nearly 34 days restart performance test. The results of this study provide insights into the strategic design of efficient catalysts for hydrogen isotope oxidation.
研究领域:
催化化学
·
核能科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xin Luo,Weilong Ren,Huanhuan Xing,Muhammad Irfan Hussain,Qumail Arshad,Yuzeng Li,Zhiyuan Liu,Changyong Liu,Zhangwei Chen
Vat photopolymerization 3D printing technique enables the precise fabrication of ceramic components with highly complex shapes and improved performance. It has been used for the preparation of Li 4 SiO 4 ceramic units, which are a promising candidate for stable tritium breeding in fusion reactions. In order to further enhance the production properties, herein metal oxide additions are proposed to combine with the previously reported generative shaping and material-forming (GSM) strategy. A remarkable theoretical density of 92.8 % and crushing load of 38.54 N reveal the effectiveness of this approach in producing robust ceramic units potentially suitable for tritium production. The study is proved to be cost-effective, highly efficient in production and most importantly to be able to produce high-performance Li₄SiO₄-based tritium breeding ceramics. Our findings provide a new insight into lithium-based tritium breeders preparation and applications, supporting their potential in fusion energy.
研究领域:
材料科学
·
核能工程
·
先进制造
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）