Lead-based reactor nuclear power has the advantages of inherent safety, compact size, light weight, long service life, and high efficiency, and it is widely applied to advanced marine equipment, unmanned underwater vehicles, and deep-sea space stations for energy and power purposes. Conducting research on lead-based reactor marine nuclear power is key to the technological innovation of energy and power for marine equipment in China. This study clarifies the application scenarios and development demands of marine nuclear power, summarizes the development status of lead-based reactor nuclear power from the aspects of technical characteristics, representative applications, and research status, and analyzes corresponding key technologies including nuclear fuel and cladding materials, key components in the primary loop, coolant processes and oxygen control, and advanced power generation technologies. Moreover, the study explores the development challenges for lead-based reactor marine nuclear power and proposes there feasible technical routes: low-temperature lead-based reactor marine nuclear power, high-temperature and high-efficiency lead-based reactor marine nuclear power, and integrated natural-circulation lead-based reactor marine nuclear power. Furthermore, we propose the following suggestions to promote the leapfrog development of marine nuclear power in China: (1) strengthening research and development (R&D) of specialized technologies for the lead-based reactor marine nuclear power and accelerating the deployment of demonstrative projects; (2) incorporating lead-based reactors into the country's major energy strategies and creating a standards system; (3) establishing national joint R&D centers and creating new models for technological innovation and industrial development.

The deep sea fuels the world's largest ecosystem, and a deep knowledge of its relevant evolutionary patterns can support the sustainable development of human society. It is difficult to carry out in-situ experiments under the extreme environmental conditions in the deep sea, which puts forward harsh requirements for the development of deep-sea scientific experiment equipment. This study summarizes the development status and problems regarding deep-sea scientific experiment equipment in China and abroad from the aspects of deep-sea test equipment and test sites, deep-sea in-situ exploration and experiment equipment, and experimental equipment for deep-sea environment simulation. China has independently developed a serial of equipment and technologies in the field of deep-sea scientific experiment equipment, and some of its advantageous directions have reached the international advanced level, which has promoted the progress of deep-sea scientific research. However, the country fails to build a mature industrial chain in terms of sophisticated equipment and associated key technologies, resulting in the restricted development of some equipment and prominent technological weaknesses. Therefore, we propose the following suggestions to promote deep-sea scientific research and the high-quality development of the deep-sea scientific experiment equipment: (1) strengthening top-level planning to coordinate technical research; (2) establishing incentive mechanisms to encourage innovation transformation; (3) building demonstration platforms and forming a standards system; (4) developing sensing technologies and accelerating the localization process; and (5) strengthening international cooperation to enhance innovation capacities.

Deep-sea underwater technology and equipment are crucial aspects to cognize the deep sea, exploit deep-sea resources, and protect the marine ecosystem. Expanding the deep-sea space faces complex environmental challenges and urgently requires support of high-level deep-sea underwater technologies and equipment. This study analyzes the components and demands for the deep-sea underwater technology and equipment and reviews the current status and development trends of the technology and equipment from four aspects: deep-sea observation/detection and perception, underwater construction, deep-sea oil and gas production, and deep-sea mineral resource collection. Moreover, this study analyzes the development status and engineering challenges in China, explores the key technology and equipment systems and key physical–mechanical mechanisms behind them, and summarizes the typical equipment and corresponding diagram. Additionally, the common key technologies of the deep-sea underwater equipment in China are summarized, including the intelligent and automation technology, precision component processing and manufacturing technology, high-precision positioning and navigation technology, high-speed communication technology, computational and analytical mechanics of large systems, and multiscale engineering design methods and technologies. Furthermore, countermeasures and suggestions are proposed aiming at achieving high-quality development of the deep-sea underwater technology and equipment in China: strengthening the top-level design of deep-sea underwater engineering to promote the establishment of a coordinating system for common key technologies, enhancing the industry influence of Chinese deep-sea underwater technical standards to explore the international market, promoting the construction of compatible and universal platforms with high quality, and training innovation professionals to provide support for the high-level development of the marine science and technology industry.

Underwater wireless communication (UWC) equipment facilitates information transmission and data exchange in underwater environments, playing vital roles in marine scientific research, underwater network monitoring, underwater collaborative operation, and marine safety maintenance. This study explores four primary UWC equipment categories: underwater acoustic communication, underwater optical communication, underwater electromagnetic communication, and underwater magnetic induction communication. It conducts in-depth analyses of the technical challenges associated with each category, comprehensively reviews their development status in China and abroad, and forecasts future trends. Focusing on the UWC industry of China, we summarize the development challenges in terms of overarching gaps, common issues, and top-level system, and propose the following development suggestions: (1) improving fundamental mechanisms and addressing common issues, (2) prioritizing breakthroughs in industry core areas, (3) elucidating the top-level system structure of the UWC equipment, and (4) enhancing safeguard measures and support policies. This study is expected to provide references for understanding the developmental trend and promoting the research and application of the UWC equipment.

Maritime search, rescue, and salvage, as the last line of defense for maritime safety, provide a reliable guarantee for the construction of a national transport system and the sustainable development of marine economy. Maritime search, rescue, and salvage equipment is an important support to fulfil public welfare duties regarding life, environment, property rescue, and emergency recovery and salvage, and to guarantee the security of a national maritime logistics supply chain. This study summarizes the global development status of maritime search, rescue, and salvage equipment as well as the research and application progress of these equipment in China from four aspects: (1) target search, location, and detection equipment, (2) life rescue equipment, (3) environment rescue equipment, and (4) salvage engineering equipment. China still lags behind developed countries regarding the maritime search, rescue, and salvage equipment in terms of search and positioning equipment, life rescue capabilities, hazardous chemical disposal capabilities, and the ability to salvage large-tonnage sunken vessels. Therefore, we propose the following suggestions to promote the high-quality development of the maritime search, rescue and salvage equipment in China: (1) increasing investment in the research and development of key equipment, (2) promoting the upgrading of these equipment, (3) strengthening the innovation capabilities of the country to enhance the intelligence level of these equipment, (4) establishing major research projects, and (5) providing industrial policy support.

Pipeline transportation is an economical and effective way for transferring carbon dioxide (CO₂) to the sea, serving as a key procedure for an offshore carbon capture, utilization and sequestration (CCUS) project, as well as a core technology for the large-scale construction of CCUS projects in China. This study clarifies the advantages of China in the construction of offshore CCUS projects, typical offshore carbon pipeline scenarios, and typical offshore CO₂ transportation modes. It also reviews the technologies and projects in China and abroad regarding offshore CO₂ transportation via pipelines. The current technologies relevant to offshore CO₂ pipeline transportation are systematically reviewed. Specifically, the process technologies include CO₂ fluid state analysis and flow assurance; corrosion evaluation, monitoring, and early warning; real-time monitoring of pipe leakage; and release of high-pressure CO₂ and its environmental impacts. The material technologies include the fracture of pipeline materials and its mitigation, high corrosion-resistant and sealing materials, key corrosion-control techniques for the long-term operation of pipelines, and corrosion risk evaluation of CO₂ injection wells. Further efforts should focus on the following aspects: material selection systems for the complex conditions during offshore CO₂ pipeline transportation, full-chain intelligent management and digital twin technologies for CO₂ pipelines, key technologies regarding the whole life-time operation of subsea CO₂ pipelines, and evaluation and assurance techniques for the transferred transportation pipelines. Furthermore, the following suggestions are proposed to promote the high-quality development of the offshore CO₂ pipeline transportation system in China: (1) promoting the planning of offshore CO₂ pipeline networks, (2) expanding interdisciplinary innovations, (3) establishing standards systems that applicable to both onshore and offshore scenarios, and (4) encouraging the participation of diversified technology service enterprises.