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Embodied energy is termed as the total (direct and indirect) energy required to produce economic or environmental goods and services. It is different from the direct energy measurement of energy consumption. Due to the importance of energy security, it has attracted increasing attention. In order to explore whether and to what extent embodied energy can provide a more innovative approach and competitive perspective to energy security issues, 2608 relevant pieces of literature from the Web of Science core collection are analyzed in this study. Results show that embodied energy has been taken seriously. Moreover, by reviewing the typical literature, this paper first summarizes the embodied energy calculation methods and models, then investigates how embodied energy provides a new perspective to energy issues, and lastly analyzes how to show value in energy security issues in its application of guiding policy-making and energy security studies. In summary, there is no doubt that embodied energy can provide a more integrated perspective on energy consumption and demand and provide a more scientific reference for policy-making to enhance energy security. However, because of data and application scope limitations, establishing a comprehensive energy security research and application system with embodied energy measurements needs hard work.

Technology transfer is a conscious knowledge transfer and diffusion, which can promote the coordinated configuration and balanced development of technological innovation elements in geographical space. From the perspective of “space of flow”, the technology transfer network is constructed. Utilizing patent technology transaction data from 2018, this study analyzes the agglomeration differentiation and spatial polarization patterns of technology transfer from network nodes, network layers, and network partition in Guangdong–Hong Kong–Macao Greater Bay Area. The conclusions are as follows: (1) The agglomeration of technology transfer is remarkable in the network, showing “two poles and two strong” as well as proximity advantages; Shenzhen and Guangzhou have become spatial poles within the network. (2) The Matthew effect is prominent and technology transfer at the spatial level is largely caused by core node interactions, while core‐edge hierarchical transmission mechanisms and geographical proximity contact characteristics are gradually developing. (3) Differences in roles between the plates are pronounced, and there is an agglomeration effect within a plate and between plates, as well as clear spillover effects.

The Sino–US trade war has prompted China to re-examine the development of manufacturing, while the energy crisis restricts such development. Scientifically planning industrial energy allocation is important for supporting industrial transformation and the upgrading of manufacturing. The embodied energy flow in China’s manufacturing was investigated by reconstructing the energy flow network; taking a systems perspective, a fine-grained analysis of the emerging patterns and evolution of these flows in the internal and external manufacturing industries was performed, thus providing useful insights for energy planning. The results show that in the internal and external networks of Chinese manufacturing, most of the embodied energy convergence and transmission is concentrated in a few industries Moreover, it is clear that industries with stronger embodied energy convergence and conductivity are generally more likely to be associated with industries with weak convergence and conductivity. Preferential selection is an important mechanism for the generation of embodied energy flow paths. The choices of the embodied energy flow paths of various industries exhibit the preference that ‘the rich get richer,’ and newly generated flow paths are more likely to be chosen for connectivity to a path of strong convergence or conductivity. The embodied energy flow patterns of the internal network of manufacturing mainly include two-focus and multi-focus convergence patterns, while that of the external network of manufacturing is mainly a two-focus transmission pattern. Within in-edge networks, communities of high-end manufacturing have gathered most of the embodied energy, while in out-edge networks, communities of traditional manufacturing have been key in the transmission of embodied energy. The impacts of the internal and external network types, and of the in-edge and out-edge types on the stability of the embodied energy flow pattern are separate, and the embodied energy flow pattern is stable. Based on these findings, an ‘energy-related industrial cluster’ model is proposed here to aid in energy convergence and transmission, as well as to realize network cluster synergy.

Pulsed fiber lasers, with high peak power and narrow pulse widths, have been proven to be an important tool for a variety of fields of application. In this work, frontier and hot topics in pulsed fiber lasers were analyzed with 11,064 articles. Benefitting from the scientometric analysis capabilities of CiteSpace, the analysis found that passively mode-locked fiber lasers with saturable absorbers (SAs) based on two-dimensional (2D) materials have become a hot research topic in the field of pulsed fiber lasers due to the advantages of self-starting operation, high stability, and good compatibility. The excellent nonlinear optical properties exhibited by 2D materials at nanometer-scale thicknesses have become a particularly popular research topic; the research has paved the way for exploring its wider applications. We summarize the performance of several typical 2D materials in ultrafast fiber lasers, such as graphene, topological insulators (TIs), transition metal dichalcogenides (TMDs), and black phosphorus (BP). Meanwhile, we review and analyze the direction of the development of 2D SAs for ultrafast fiber lasers.