The study on the multi-scale hydrological cycle and global connection is important to deeply understand the law of global water cycle change and to predict its future change trend using different scale models. That will help us avoid the adverse effects of human activities, deal with basin, regional and global changes, and improve the ability of human beings to adapt to different environments. In this paper, bibliometric method is used to analyze the development trend, research force distribution and research hotspots in the field of multi-scale hydrological cycle and global connection, so as to provide reference for scientific research and decision-making in related fields.

The hydrological cycle in the Asia-Pacific region is an important part of the global climate and environment system. Based on SCIE literatures retrieved from Web of Science database, followed by manual data cleaning and content reading, 3353 ones related to hydrological change and marine process in Asia Pacific region were selected. In order to provide macro and general information support and decision-making reference for related research, the current research situations in this field were analyzed by bibliometric method, including the trend of literature’s number, main research countries, main research institutions, main researchers, key research contents, hot research topics and high impact papers.

Hydrological cycle is a link in the climate system, in which ocean-land-atmosphere interactions involve various complex physical processes. The couplings among the interactions, as important driving forces of climate change, have exerted far-reaching influence on the global climate change. Thus, studying the coupling mechanisms among ocean-land-atmosphere interactions in the hydrological cycle is a key research direction in the fields of atmospheric science, hydrology, oceanography and earth science. In order to explore the international development trend of this field, we took the publications (SCIE) as the literature data source, and used the professional analysis tool (Derwent Data Analyzer) to clean and exploit the data. By analyzing bibliographical particulars such as countries, institutions, journals and authors' key words in the paper description items, we obtained the international competition pattern over the years. The results presented here provide important reference for grasping the global basic research situation in this research direction.

The electronic information industry is one of the important battlefields in the global competition. Analyzing and comparing the knowledge evolution characteristics of electronic information industry in the global Greater Bay Areas is of great significance for improving the industry development in Guangdong-Hong Kong-Macao Greater Bay Area. Using Incopat as the data source, the science-technology-industry relevancy of the industry in the four Bay Areas—Tokyo Bay Area, New York Bay Area, San Francisco Bay Area and Guangdong-Hong Kong-Macao Greater Bay Area — were investigated by analyzing patent citation scientific documents (non-patent-references, NPR). The study found that the sub-industries in the Guangdong-Hong Kong-Macao Greater Bay Area already have certain competitiveness, but the excellent basic research results is obviously insufficient, as well as the absorption of scientific research results by patents. Hong Kong has strong scientific research capabilities and a clear lead in the Guangdong-Hong Kong-Macao Greater Bay Area. Strengthening the cooperation between Guangdong and Hong Kong, enhancing the strength of local research and development, and promoting the generation and transformation of original research results is a top priority.

As a new water treatment technology, Electrochemical Advanced Oxidation Processes (EAOPs) has attracted much attention. In this study, the overall development of the EAOPs field was studied bibliometrically, hoping to help researchers to better grasp the development context of the field, and provide references for scientific research. Based on the research articles on EAOPs retrieved from the database of SCIE, this paper analyzed the developing trends of the research field including the perspectives of publication time distribution, region distribution, journal distribution, high-yield institutions distribution, high-yield authors and research topics, by using visualization tools such as DDA, VOSviewer and CiteSpace. Results showed that the current relevant research mainly focuses on China, the United States and Spain. Recent trends indicate that electrochemical oxidation technology will usher in a period of rapid development. The research focus has also gradually shifted from the electrochemical advanced oxidation mechanism to the electrochemical advanced oxidation equipment and other systems. In addition, in order to further improve the mass transfer of pollutants, it will be a new hot spot to increase the reaction participation rate of hydroxyl radicals (hydroxyl radicals have nanosecond lifetime).