The last Far Eastern leopards survived at the junction of the Southwest of Primorsky Krai in Russia and the Laoyeling-Dalongling in Jilin and Heilongjiang provinces in China. By the year 2000, there were only 30–35 individuals living in an area of approximately 3000 km2. Thanks to conservation efforts, this endangered subspecies has moved away from the edge of extinction, with more than 150 individuals living in an area over 14,000 km2 in 2022. Reliable protection of key habitats has played a crucial role in this success. Over the past 25 years, the transboundary network of protected areas dedicated to the conservation of the Far Eastern leopard has increased 12 times, from 1532 km2 to 18,961 km2, covering 12,636 km2, or 90 percent of its current range. The latest step was the proclamation in 2024 of the Sino-Russian transboundary protected area “Land of Big Cats”. This includes the Kedrovaya Pad Nature Reserve, the Land of the Leopard National Park with a buffer zone in Russia (3694 km2), and the Northeast Tiger Leopard National Park in China (14,612 km2). According to our estimates, this will ensure the long-term preservation of 17,239 km2 of suitable habitats, which will allow for the maintenance of a potential population of at least 300 Far Eastern leopards.
Amid persistent environmental pressures linked to energy dependence and structural inefficiencies, this study represents one of the first empirical attempts to concurrently investigate the effects of renewable energy, green technology, environmental taxes, economic growth, energy imports, and government effectiveness on greenhouse gas emissions (GHGE) using data updated through 2024 for Nigeria’s evolving economy. Using the “Autoregressive Distributed Lag” (ARDL) approach with “Granger causality” analysis, the results confirm a stable long-run association between the indicators. Renewable energy and energy imports indicate a negative correlation with GHGE in both the near and long term, supporting Nigeria’s low-carbon transition. Economic growth reduces emissions in the near term but shows no significant long-run effect. Environmental taxes exhibit a weak positive association with emissions, reflecting enforcement and institutional limitations, while green technology and government effectiveness show negative but insignificant impacts. The causality findings reveal unidirectional links from environmental taxes to emissions and from emissions to government effectiveness. The results highlight the importance of strengthening renewable energy, diversifying energy sources, and enhancing institutional capacity to achieve sustainable environmental outcomes in Nigeria.
Developing an oxygen evolution reaction catalyst that exhibits both high catalytic activity and robust stability in acidic media remains a significant challenge to date. In this work, a RuZrOx/Ti-1 catalyst was successfully constructed on a Ti mesh substrate via a facile one-step pyrolysis method. Physical characterization reveals that the as-prepared RuZrOx/Ti-1 catalyst exhibits a densely packed nanosphere morphology on its surface, accompanied by abundant pores, which can provide a rich interface for the oxygen evolution reaction. The RuZrOx/Ti-1 catalyst achieves a low overpotential of only 199 mV for the OER at a current density of 10 mA·cm−2 and demonstrates excellent long-term durability, operating stably for 400 h at this current density. In summary, this work provides a viable strategy for designing high-performance acidic OER catalysts, thereby paving the way for the advancement of electrodes for water oxidation.
Wide Bandgap (WBG) semiconductors, particularly Silicon Carbide (SiC), have become pivotal in advancing high-efficiency, high-power-density systems. Cascode configurations, combining a high-voltage SiC JFET with a low-voltage Si MOSFET, enable Normally-OFF operation while leveraging SiC’s superior switching and thermal properties. However, co-packaging these devices introduces critical design challenges related to parasitic inductance, thermal management, and reliability. This study investigates the impact of bonding configuration and die-attach material selection on dynamic and thermal performance in SiC-based modules. Double Pulse Test (DPT) results reveal that direct bonding provides a better tradeoff between switching losses and dynamic operation stability, mitigating VDS overshoot, gate oscillation, and EMI risk, thereby improving switching stability under system-level stress. Conversely, indirect bonding increases inductance, amplifying oscillations and dynamic stress during turn-off events. Thermal analysis demonstrates that while system-level cooling dominates Rthja, the adoption of sintered silver (Ag) as a die-attach material achieves ~20% reduction in Rthjc, lowering junction temperatures and enhancing reliability for high-power applications. These findings underscore the importance of interconnect design and attach material optimization in achieving robust, high-efficiency operation of wide-bandgap devices.
Optical fiber sensing technology offers high sensitivity, electromagnetic immunity, and distributed sensing capabilities, with broad applications in environmental, biomedical, and industrial monitoring. However, its reliance on heavy-metal-doped glasses, rare-earth elements, and non-biodegradable polymers imposes significant environmental burdens across their lifecycle. This review establishes a systematic framework based on the Twelve Principles of Green Chemistry to assess and redesign optical fiber sensing materials, including silica, soft glass, and polymer matrices, as well as functional coatings, fluorescent probes, and plasmonic nanostructures. It highlights green alternatives such as sol-gel synthesis, bio-based polymers, carbon quantum dots, and biosynthesized nanoparticles. A multi-dimensional sustainability assessment, covering performance, environmental impact, economics, and social factors, identifies key challenges such as performance-environment trade-offs and scaling-up costs. Future pathways integrating AI-assisted design, additive manufacturing, modular systems, and policy support are proposed. The study argues that green attributes and high performance are synergistic, positioning green optical fiber sensing as essential for achieving circular economy goals and UN Sustainable Development Goals.
