Hydrogen storage and transportation technologies are key components in the hydrogen energy industry chain and have the potential to become an industry with benefits of more than ten billion in the future. Currently, mainstream technologies include high-pressure gas hydrogen storage, low-temperature liquid hydrogen storage, and low-pressure solid hydrogen storage, while organic liquid hydrogen storage is still in the application demonstration phase. This paper reviewed recent research, development, and application advancements in these hydrogen storage and transportation technologies, analyzed the associated challenges, and predicted future research and development directions. Overall, hydrogen storage and transportation technologies show substantial development potential, but continued breakthroughs in cost reduction, efficiency enhancement, safety assurance, and localization improvements are necessary to drive the rapid growth of the hydrogen energy industry.

The rapid development of 5G communication, artificial intelligence, Internet of Things, and other fields has put forward demanding requirements for existing communication systems. At present, optical interconnection with low latency, low power consumption, and large capacity is receiving widespread attention as a new communication solution, among which optical interconnection based on silicon-based photoelectrons is one of the best technologies. As the core device, silicon-based germanium photodetector is crucial for the development of silicon-based optical interconnection. This article analyzed the technological development of silicon-based germanium photodetectors, systematically summarized the new structure, key processes, and technological innovations in the development of high-performance silicon-based germanium detectors, and predicted the development trend, hot technologies, and research directions, with a view to providing support for the construction and development of China’s optical communication systems.

As the development of offshore oil and gas resources ventures into deeper waters, the environmental loads escalate significantly, which presents formidable challenges to the operational safety and maintenance costs of offshore pipelines. Compared with conventional steel pipes, offshore flexible pipes have the advantages of strong corrosion resistance, great flexibility, and high installation efficiency, thus becoming pivotal equipment for the transportation of offshore oil and gas. This article reviewed the current state of three application technologies of offshore flexible pipes, including submarine flexible pipes, offshore flexible risers, and low-temperature transportation flexible pipes for liquefied natural gas. It also analyzed the challenges in the research and application of offshore flexible pipes and proposed development trends and suggestions for offshore flexible pipe transportation technologies.

Complex wells, with horizontal wells as the basic features, serve as advanced well-type technologies for the efficient development of complicated oil & gas fields with low-permeability, unconventional, marine, and deep features, and they have attracted a lot of attention in China and abroad. This article first introduces the concept of complex wells and their application scenarios. Next, some important developments in directional drilling theories and technologies for complex wells are sorted out, including rotary steerable drilling technology, magnetic steering drilling technology, and extended-reach drilling technology. At last, the challenges in directional drilling of complex wells are analyzed, and the corresponding suggestions are put forward, so as to provide support for directional drilling of complex wells in terms of theoretical and technical innovations.

Investigating national strategies, scientific frontiers, and industrial development, deep-sea biological research serves to evaluate carbon flux and storage, understand deep-sea ecosystem changes and responses, and explore new deep-sea biological resources at full-ocean depth. Deep-sea environment simulation technology and deep-sea in situ test technology have been developed to observe, detect, and analyze the physiological state, ecological function, and evolution process of organisms in the deep sea and thereby to meet the needs of deep-sea biological research. This paper summarizes the development courses and technical characteristics of deep-sea environment simulation technology and deep-sea in situ test technology, discusses their future development prospects, and proposes development strategies and suggestions to help promote China’s strength in deep-sea technologies and deep-sea bioscience research.