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Groundwater nitrate contamination is a worldwide water environment problem with few phased summaries in this field. Here, 14 407 articles were selected from the Web of Science database for the years 1968—2022 to analyze the development trends and current hotspots in the field of groundwater nitrate contamination research with bibliometric visualization analysis software (VOS viewer). The results showed that: (1) The number of relevant publications has been exponentially increasing. The published journals are mainly related to environmental science and water resources, indicating an important role in this field. (2) The results from the publication institutions and funding institutions show that more than half of the total number of articles from the top ten publication institutions and funding institutions are from the United States and China. (3) The main issues in groundwater nitrate contamination research can be summarized as four subsets: source tracing, migration and transformation mechanisms, pollution remediation, and risk assessment. Among them, pollution remediation has the most keywords, demonstrating the importance of this research area. (4) From 1990 to 2014, the research hotspots in groundwater nitrate research were mainly focused on source tracing and migration and transformation mechanisms. Specifically, the main topic was the identification of nitrate pollution sources during the stage from 1990 to 1998, while the focus shifted to the methods for identifying nitrate pollution sources from 1999 to 2014, with isotopes and models being particularly effective. For the recent stage from 2015 to 2022, the research hotspots have shifted to risk assessment. The bibliometric analysis results in the field of groundwater nitrate pollution can provide some reference for the direction of this field.

With the rapid development of the e-commerce industry, e-commerce live broadcasting has become a crucial retail outlet for consumers. However, live broadcasting e-commerce faces the “anchor dilemma,” such as the difficulty of finding a suitable live anchor, the collapse of the live anchor, and so on. With the advent of the meta-universe era and the progress of artificial intelligence, e-commerce virtual anchors have become an effective way to solve the “anchor dilemma” in practice. Virtual anchors can carry goods like real people, replacing some real-life e-commerce anchors. Personification is a significant feature of virtual humans. E-commerce virtual anchoring has the ability, the appearance, and the cultural identity of personification. Consumer citizenship behavior is a kind of spontaneous altruistic behavior that improves the overall quality of e-commerce virtual anchor live broadcasts. Through the Stimulus Organism Response (SOR) model, this study explores the personification mechanism of virtual anchors on consumer citizenship behavior in the live broadcast scene of e-commerce. Through empirical research on 343 questionnaires, this study finds that the personification of e-commerce virtual anchors has a positive effect on consumer citizenship behavior and shopping value; and in turn, shopping value has a positive effect on consumer citizenship behavior. This study suggests applying virtual anchors in e-commerce live broadcasting based on the research results.

Nanomaterials with unique structures and functions have been widely used in the fields of microelectronics, biology, medicine, and aerospace, etc. With advantages of high resolution and multi functions (e.g., milling, deposition, and implantation), focused ion beam (FIB) technology has been widely developed due to urgent demands for the 3D fabrication of nanomaterials in recent years. In this paper, FIB technology is illustrated in detail, including ion optical systems, operating modes, and combining equipment with other systems. Together with the in situ and real-time monitoring of scanning electron microscopy (SEM) imaging, a FIB-SEM synchronization system achieved 3D controllable fabrication from conductive to semiconductive and insulative nanomaterials. The controllable FIB-SEM processing of conductive nanomaterials with a high precision is studied, especially for the FIB-induced deposition (FIBID) 3D nano-patterning and nano-origami. As for semiconductive nanomaterials, the realization of high resolution and controllability is focused on nano-origami and 3D milling with a high aspect ratio. The parameters of FIB-SEM and its working modes are analyzed and optimized to achieve the high aspect ratio fabrication and 3D reconstruction of insulative nanomaterials. Furthermore, the current challenges and future outlooks are prospected for the 3D controllable processing of flexible insulative materials with high resolution.

With the continuous development of in-line inspection, two or more rounds of in-line inspection have been performed to most pipelines, and a large number of in-line inspection data are obtained. Due to the influence of external environment and detection error, the in-line inspection data in multiple rounds have deviations in mileage, defect identification and quantification, they are difficult to be aligned rapidly, and manual alignment is a huge workload. In order to study the rapid alignment method of in-line inspection data, an in-line inspection data alignment algorithm model was established based on the massive in-line inspection data, and with the model, the rapid alignment of in-line inspection data was realized, for which application test was conducted with the in-line inspection data of different units in different formats. The test results show that: the achievable alignment with this method is 100% for the features of pipeline valve and tee, over 99% for pipe joint and at least 90% for elbow. Further, based on the method, the inspection data could be quickly mined and analyzed in depth and the development trend of defects on pipe body could be predicted, so that data support could be provided for internal and external corrosion control and management of pipe body, the risks of pipe body could be pre-controlled, and the pipeline integrity management could be improved.

In the context of today’s rapid economic development and increasingly strict ecological protection, interactions between humans and wildlife will intensify. Therefore, we need to identify the spatial distribution of such interactions and to take measures to mitigate possible negative interactions. Using the Three-Rivers Source Region as a case study, we combined species habitat suitability, species feeding habits, species conservation levels and human impact intensity to construct a “human-wildlife spatial interaction index” (HWSII) to evaluate the intensity of human-wildlife spatial interactions. The overall level of HWSII was relatively low in the Three-River Source Region. Higher potential human-wildlife interactions occurred in areas with roads and railways. Areas of relatively high interactions between carnivores and livestock were mainly located in the southern part of the study area, and those with relatively high interactions between herbivores and livestock appeared in the western and eastern parts. Managers in these areas should consider mitigation measures. Although developed for a specific region of China, the ‘human-wildlife spatial interaction index’ could have application in other areas of the world for setting a baseline reference to identify areas with the potential for high levels of human-wildlife interactions and pinpoint places where potential negative interactions can be mitigated.