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Hydrothermal liquefaction (HTL) is an effective way to treat solid wastes with high moisture content. The co-hydrothermal liquefaction (co-HTL) experiments of oily scum and poplar sawdust biochar at the different hydrothermal temperatures were performed in this work. The changes of the appearance and components of the liquid products were comprehensively studied. The results showed that the addition of biochar into oily scum significantly reduced the moisture content of the residue hydrochars obtained after co-HTL. As the hydrothermal temperature increased, the liquid products obtained from co-HTL turned clearer and lighter in color, and the recovery rate of the liquid products significantly increased. The co-HTL of bi-ochar and oily scum could effectively improve the liquid quality and enhance the recovery rate of hydrochars. The carbon numbers of the liquid products obtained from co-HTL were concentrated in C5-C11, which were main compositions of gas-oline. This work can provide basic data and theoretical reference for oily scum efficient treatment and engineering practice.

For LCC-HVDC system with renewable energy integration, the randomness and variability of renewable energy will cause wide variations in the short-circuit capacity provided by the AC system. To effectively assess the supporting capability of the AC system, this paper proposes an active short-circuit capacity identification method for LCC-HVDC system considering the integration of renewable energy. First, an equivalent AC system was established based on Thevenin theorem, and the equivalent electromotive force was calculated. Then, the sensitivity of the voltage at the point of common coupling (PCC) to the active and reactive power flowing through the PCC was computed. Through sensitivity analysis, the key factors affecting the identification of the equivalent resistance and reactance were studied. Based on this, an active short-circuit capacity identification method combining the switching of filters and changes in DC power was proposed. Finally, a simulation model of LCC-HVDC system with grid-following wind power integration was built in PSCAD/EMTDC for verification. The results show that the proposed method is applicable to AC systems with different impedance characteristics. Moreover, with the increase of the grid-following renewable energy, the short-circuit capacity provided by the AC system shows a decreasing trend. The proposed method can actively identify the short-circuit capacity of AC system with renewable energy, thus provides a theoretical basis for the development of control strategies for LCC converter station under different AC system strength.

Climate change is an emerging global health crisis, disproportionately affecting low- and middle-income countries (LMICs) where health outcomes are increasingly compromised by environmental stressors such as pollution, natural disasters, and human migration. With a focus on promoting health equity, Global Surgery advocates for expanding access to surgical care and enhancing health outcomes, particularly in resource-limited and disaster-affected areas like LMICs. The healthcare industry—and more specifically, surgical care—significantly contributes to the global carbon footprint, primarily through resource-intensive settings, i.e. operating rooms that generate greenhouse gases and substantial medical waste. Therefore, Global Surgery efforts aimed at improving surgical access through an increase in surgical volumes may inadvertently exacerbate health challenges for vulnerable populations by further contributing to environmental degradation. This predicament is particularly pronounced in LMICs, who already suffer from a disproportionate share of the global burden of disease, and where the demand for surgery is rising without corresponding resilient infrastructure. LMICs face a double jeopardy of health inequity coupled with climate vulnerability. As a movement positioned to improve health around the world, Global Surgery has an increasingly significant role in envisioning and ensuring a sustainable future. Global Surgery initiatives must prioritise sustainable infrastructure in both high-income countries (HICs) and LMICs, all while accounting for the unequal polluting contributions between HICs and LMICs and, consequently, moral responsibilities moving forward. Moreover, through targeting upstream causes of poor health at urban and perioperative levels, Global Surgery’s interventions may help to reduce the global burden of disease—avoiding preventable surgeries and their carbon footprints from the outset. Altogether, Global Surgery and climate change are two matters of social justice whose solutions must synergistically centralise the health of both the planet and its most vulnerable people.

Les conséquences du changement climatique sont particulièrement aiguës au Kenya, où 80 % des terres sont arides ou semi-arides. Quelle perspective critique et constructive le concept d’habitabilité peut-il offrir dans ce contexte ? Fondé sur un travail de terrain réalisé au Kenya en 2022 et 2023, cet article entend affiner une définition in situ de l’habitabilité, en utilisant exclusivement des données qualitatives issues de deux phases de recherche, complétées par des exercices de vidéo-cartographie. Loin de proposer une lecture positiviste de l’habitabilité, portée par une conception exclusivement mécanique et linéaire des dynamiques de mobilité, cette étude propose de mieux relier l’habitabilité aux pratiques quotidiennes, aux habitudes, aux solidarités, voire aux résistances qui constituent la vie ordinaire des habitants des communautés et des personnes déplacées. L’habitabilité se situerait alors au cœur de l’intrication entre socialité et spatialité, entre social et biologique, qui définit – selon Stanley Cavell – la forme de vie humaine. The consequences of climate change are particularly acute in Kenya, where 80% of the land is arid or semi-arid. What critical and constructive perspective can the concept of habitability offer in this context? Based on fieldwork carried out in Kenya in 2022 and 2023, this article aims to refine an in-situ definition of habitability, using exclusively qualitative data from two research phases, supplemented by video-mapping exercises. Far from proposing a positivist reading of habitability, driven by an exclusively mechanical and linear conception of mobility dynamics, this study proposes to better link habitability to the daily practices, habits, solidarities and even resistances that make up the ordinary lives of community dwellers and displaced persons. Habitability would then lie at the heart of the intricacy between sociality and spatiality, between the social and the biological, which defines – according to Stanley Cavell – “the human form of life.”

Achieving the Sustainable Development Goals (SDGs) is crucial for addressing global environmental challenges. SDG 13 calls for urgent climate action, while SDG 7 promotes sustainable energy. These objectives are particularly relevant to China, where transport-related CO2 emissions continue to rise due to urbanization, industrial growth, and increasing energy demand. This study examines the impact of economic governance, population aging, human capital, financial innovation, GDP growth, and energy transition on China’s transport-related CO2 emissions, using quarterly data from 2006Q1 to 2018Q4. The Method of Moments Quantile Regression (MMQR) is applied to analyze heterogeneous effects across different emission levels. The findings reveal that economic governance (ECOG), energy transition (ENT), and human capital (HI) significantly reduce transport CO2 emissions (TCO2E) by enhancing institutional effectiveness and promoting clean energy adoption. In contrast, population aging (POPAGE), financial innovation (FI), and GDP contribute to higher emissions by increasing energy consumption and private transport dependency. These insights highlight the need for stronger governance frameworks, sustainable financial policies, and increased investment in renewable energy. Policymakers should strengthen environmental regulations, expand green financing initiatives, and enhance public transport infrastructure to align with SDGs 7 and 13. By implementing these strategies, China can make significant progress toward reducing transport emissions, achieving carbon neutrality, and ensuring long-term sustainability.

Using 1281 pedestrian tunnels scattered over Stockholm, Sweden’s capital, we investigate the nature and distribution of graffiti in three types of underpasses (pathways, cycleways, and stairways). Combining crowdsourced data and police records, we compare graffiti levels and geography using fieldwork inspections, regression models, and Geographic Information Systems (GIS). The findings indicate that graffiti recorded to the police is present in only a quarter of the pedestrian tunnels, suggesting that recorded practices are concentrated in specific underpasses. Graffiti is more commonly found in larger tunnels, particularly cycling underpasses. Proximity to metro stations, schools, and the presence of young males in the area are factors linked to graffiti occurrence, although not consistently. These results highlight the complexities of relying on graffiti records for public space management, particularly the challenges professionals face in aligning the maintenance of pedestrian tunnels with urban sustainability goals. QC 20250317

The power module package insulation is prone to partial discharge (PD) under fast square pulses, which is one of the main reasons for power module packaging failure. However, there are few studies on PD under square electrothermal coupling stress. One of the important reasons is that the electromagnetic interference and displacement current generated by the rising and falling edges of the square pulse seriously interfere with the detection of PD. To address this problem, this paper proposes a multi-spectral optical detection method with high sensitivity and strong anti-interference. Based on the multi-spectral synchronous detection platform, the high-temperature PD characteristics of power module package insulation under square pulses are studied. The results show that the partial discharge inception voltage (PDIV) decreases with increasing temperature, and the intensity of the PD multi-spectral signal increases with increasing temperature. In addition, the statistical analysis of the maximum optical signal intensity, cumulative optical signal intensity, number of PDs, and phase of PD under square pulse shows that with the increase of temperature, the maximum optical signal intensity and cumulative optical signal intensity of PD increase, and PD events mostly occur on both sides of the square pulse. Among them, the optical signal in the near-ultraviolet band is dominant, and the near-infrared signal has an obvious increase trend. These findings are of great significance for the reliability detection of power module package insulation.