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The ocean covers 70% of the earth’s area, and the seawater uranium is more than 1000 times that of terrestrial uranium ore. In order to increase the power generation and ensure the sustainable operation of nuclear power plants, the development of unconventional uranium resources is of great significance. As an effective means to solve shortage of terrestrial uranium resources, uranium extraction from seawater has received extensive attention in recent years. At present, many methods including membrane separation, chemical deposition, solvent extraction, ion exchange, reduction and adsorption have been applied to uranium extraction from seawater. This paper focuses on the recent research progress of adsorption method used inorganic materials, organic materials, carbon materials as adsorbent, and emerging electroreduction technologies, and further discusses the challenges and opportunities of these two methods.

Quantum chemical calculations were used to determine the energetic viability of several mechanisms for formation of ladderanes from oligocyclopropanes. Pathways involving radical cations, diradicals, and carbocations were considered, and a hybrid of carbocation and radical cation pathways was predicted to have the lowest overall barrier.

As the most important nuclear fuel for nuclear power operation, the safe supply of uranium resources is the key to ensure the sustainable development of nuclear power in China. Uranium extraction from seawater has important and longterm strategic significance to ensure the sustainable development of nuclear power in China. With the updating and development of uranium extraction technology from seawater, the research work of uranium extraction from seawater is facing new opportunities and challenges. Based on the research status of uranium extraction from seawater at home and abroad, this paper puts forward the future plan and prospect of uranium extraction from seawater, which is proposed by “Seawater Uranium Extraction Technology Innovation Alliance” led by China National Nuclear Corporation. It points out the research direction of uranium extraction from seawater in the future, and provides technical support for uranium extraction from seawater to industrialization.

Natural uranium is an important material basis to ensure the sustainable and stable development of national nuclear energy. Ocean contains abundant natural uranium resources, and the extraction of uranium from seawater is of great strategic and economic significance for supplementing and improving our country’s uranium supply system and realizing the autonomy of natural uranium supply. In this paper, the latest progress in the research direction of seawater uranium extraction technology in recent years is reviewed. This paper mainly summarizes the research results of adsorption materials and field tests for uranium extraction from seawater at home and abroad, and prospects the future development of uranium extraction from seawater.

2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (HNIW)-based polymer-bonded explosives (PBXs) were prepared through an aqueous suspension method using cellulose acetate butyrate (CAB) or fluorine rubber F2311 as a binder. Then the variation rules of mass, surface micro-topography, mechanical properties, thermal decomposition performance, detonation velocity and mechanical sensitivity of the samples before and after accelerated aging tests for different durations were measured. Then the variables of the samples that before and after accelerated aging tests for different durations, will be measured, these variables including the variation rules of mass, surface micro-topography, mechanical properties, thermal decomposition performance, detonation velocity, and mechanical sensitivity. The PBX columns showed an acceptable mass loss of less than 1%, after accelerated aging tests. The surface of the PBX samples became more and more uneven as the aging duration prolonged, which was in a good agreement with the order of mass loss. Moreover, the tensile strength, the thermal stability, the detonation velocity and the mechanical sensitivity of the samples were not significantly affected by the aging process, suggesting that the PBXs remained valid after an accelerated aging test at 60°C for 60 days. A further estimation using the modified Arrhenius equation revealed that the storage life at ambient temperature (20°C) of the HNIW-based PBXs was over 10 years, which satisfies the application demands for explosives. [ABSTRACT FROM AUTHOR]

Dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) is a promising candidate for high-energy explosive (e.g. HMX), which can be used as the main component in composite explosive formulations processed through a melting method. In the present study, TKX-50-based explosive composites were prepared using 2,4,6-Trinitrotoluene (TNT) or TNT/wax as the carrier, and were compared with HMX-, 3-nitro-1,2,4-triazol-5-one (NTO)-, and hexahydro-1,3,5-trinitro-1,3,5-s-triazine (RDX)-based formulations. Crystal stability, surface micro-topography, thermal decomposition performance, mechanical property, thermal sensitivity, and mechanical sensitivity of the composites were comprehensively investigated. Overall, TKX-50-based formulations exhibited improved properties with a superior safety performance compared to HMX- and RDX-based formulations and better mechanical properties than NTO-based formulations. [ABSTRACT FROM AUTHOR]