Frontiers of Energy Storage Technologies

Energy storage technologies (ESTs) play a crucial role in ensuring energy security and addressing the challenges posed by climate change. They enable us to overcome the mismatch between energy supply and demand caused by the intermittent and unpredictable nature of renewable energy sources. The identification of research frontiers in ESTs has primarily relied on expert experience and has been limited to specific areas of study. However, there is a relative lack of data-driven approaches to identify these frontiers. In this study, we employed an integrated technique combining bibliographic coupling and sliding window analysis to identify the research frontiers in ESTs and understand their evolution over time. Our study reveals 19 research frontiers in ESTs distributed across four knowledge domains: electrochemical energy storage, electrical energy storage, chemical energy storage, and energy storage systems. Among these frontiers, two noteworthy areas are aqueous zinc batteries (AZBs) and two-dimensional transition metal carbon-nitride composites (MXenes). By identifying these research frontiers, our study provides insights into the potential future directions for research and development (R&D) deployment in energy storage technologies

Investigating mechanism of inclined CPT in granular ground using DEM

Abstract. This paper presents an investigation on mechanism of the inclined 1 cone penetration test (CPT) using the numerical discrete element method (DEM). 2 A series of penetration tests with the penetrometer inclined at different angles 3 (i.e., 0°,15°, 30°, 45° and 60°) were numerically performed under µ=0.0 and 4 µ=0.5, where µ is the frictional coefficient between the penetrometer and the soil. 5 The deformation patterns, displacements of soil particles adjacent to the cone tip, 6 velocity fields, rotations of the principal stresses and the averaged pure rotation 7 rate (APR) were analyzed. Special focus was placed on the effect of friction. The 8 DEM results showed that soils around the cone tip experienced complex 9 displacement paths at different positions as the inclined penetration proceeded, 10 and the friction only had significant effects on the soils adjacent to the 11 penetrometer side and tip. Soils exhibited characteristic velocity fields 12 corresponding to three different failure mechanisms and the right side was easier 13 to be disturbed by friction. Friction started to play its role when the tip approached 14 the observation points, while it had little influence on rotation rate. The 15 normalized tip resistance (q c = f /σ v0 ) increased with friction as well as inclination 16 angle. The relationship between q c and relative depth (y/R) can be described as q c 17 =a×(y/R) -b , with parameters a and b dependent on penetration direction. The 18 normalized resistance perpendicular to the penetrometer axis q p increases with the 19 inclination angle, thus the inclination angle should be carefully selected to ensure 20 the penetrometer not to deviate from its original direction or even be broken in 21 real tests. 2

The Orbitofrontal Cortex Gray Matter Is Associated With the Interaction Between Insomnia and Depression

Insomnia and depression are highly comorbid symptoms in both primary insomnia (PI) and major depressive disorder (MDD). In the current study, we aimed at exploring both the homogeneous and heterogeneous brain structure alteration in PI and MDD patients. Sixty-five MDD patients and 67 matched PI patients were recruited and underwent a structural MRI scan. The subjects were sub-divided into four groups, namely MDD patients with higher or lower insomnia, and PI patients with higher or lower severe depression. A general linear model was employed to explore the changes in cortical thickness and volume as a result of depression or insomnia, and their interaction. In addition, partial correlation analysis was conducted to detect the clinical significance of the altered brain structural regions. A main effect of depression on cortical thickness was seen in the superior parietal lobe, middle cingulate cortex, and parahippocampal gyrus, while a main effect of insomnia on cortical thickness was found in the posterior cingulate cortex. Importantly, the interaction between depression and insomnia was associated with decreased gray matter volume in the right orbitofrontal cortex, i.e., patients with co-occurring depression and insomnia showed smaller brain volume in the right orbitofrontal cortex when compared to patients with lower insomnia/depression. These findings highlighted the role of the orbitofrontal cortex in the neuropathology of the comorbidity of insomnia and depression. Our findings provide new insights into the understanding of the brain mechanism underlying comorbidity of insomnia and depression

Origin and Radiative Forcing of Black Carbon Aerosol: Production and Consumption Perspectives.

Air pollution, a threat to air quality and human health, has attracted ever-increasing attention in recent years. In addition to having local influence, air pollutants can also travel the globe via atmospheric circulation and international trade. Black carbon (BC), emitted from incomplete combustion, is a unique but representative particulate pollutant. This study tracked down the BC aerosol and its direct radiative forcing to the emission sources and final consumers using the global chemical transport model (MOZART-4), the rapid radiative transfer model for general circulation simulations (RRTM), and a multiregional input-output analysis (MRIO). BC was physically transported (i.e., atmospheric transport) from western to eastern countries in the midlatitude westerlies, but its magnitude is near an order of magnitude higher if the virtual flow embodied in international trade is considered. The transboundary effects on East and South Asia by other regions increased from about 3% (physical transport only) to 10% when considering both physical and virtual transport. The influence efficiency on East Asia was also large because of the comparatively large emission intensity and emission-intensive exports (e.g., machinery and equipment). The radiative forcing in Africa imposed by consumption from Europe, North America, and East Asia (0.01 Wm-2) was even larger than the total forcing in North America. Understanding the supply chain and incorporating both atmospheric and virtual transport may improve multilateral cooperation on air pollutant mitigation both domestically and internationally

Climate change : strategies for mitigation and adaptation

The sustainability of life on Earth is under increasing threat due to humaninduced climate change. This perilous change in the Earth's climate is caused by increases in carbon dioxide and other greenhouse gases in the atmosphere, primarily due to emissions associated with burning fossil fuels. Over the next two to three decades, the effects of climate change, such as heatwaves, wildfires, droughts, storms, and floods, are expected to worsen, posing greater risks to human health and global stability. These trends call for the implementation of mitigation and adaptation strategies. Pollution and environmental degradation exacerbate existing problems and make people and nature more susceptible to the effects of climate change. In this review, we examine the current state of global climate change from different perspectives. We summarize evidence of climate change in Earth’s spheres, discuss emission pathways and drivers of climate change, and analyze the impact of climate change on environmental and human health. We also explore strategies for climate change mitigation and adaptation and highlight key challenges for reversing and adapting to global climate change

Methodology and applications of city level CO2 emission accounts in China

China is the world's largest energy consumer and CO2 emitter. Cities contribute 85% of the total CO2 emissions in China and thus are considered as the key areas for implementing policies designed for climate change adaption and CO2 emission mitigation. However, the emission inventory construction of Chinese cities has not been well researched, mainly owing to the lack of systematic statistics and poor data quality. Focusing on this research gap, we developed a set of methods for constructing CO2 emissions inventories for Chinese cities based on energy balance table. The newly constructed emission inventory is compiled in terms of the definition provided by the IPCC territorial emission accounting approach and covers 47 socioeconomic sectors, 17 fossil fuels and 9 primary industry products, which is corresponding with the national and provincial inventory. In the study, we applied the methods to compile CO2 emissions inventories for 24 common Chinese cities and examined uncertainties of the inventories. Understanding the emissions sources in Chinese cities is the basis for many climate policy and goal research in the future