As global construction solid wastes surged and to achieve the carbon peak and carbon neutrality goals, the application of fully recycled coarse aggregate concrete (FRCAC, 100% replacement rate) in structural engineering has emerged as a breakthrough solution to addressing resource-environmental constraints and reshaping low-carbon structural systems. However, current codes and standards lack long-term empirical data under actual service conditions, constraining technological updates and large-scale application. This study aims to break technological bottlenecks, drive code upgrades, and promote low-carbon application. It explores the service performance of FRCAC structures using a 30-m-span simply supported beam as the engineering prototype. Under self-weight loading, the maximum compressive stress at the edge of the compression zone of FRCAC is approximately 50% of its axial compressive strength, simulating the stress state under actual loading conditions, thus enabling quantitative analysis of performance evolution mechanisms and low-carbon benefits under long-term coupled effects of mechanical loading and environmental exposure. Through designing comparative beams with equivalent reinforcement and water-to-binder ratios between FRCAC and conventional concrete, we established a comprehensive framework covering material preparation, component behaviors, and carbon benefit quantification. We tracked deformations, crack patterns, and carbonation depth evolution over 4-year service periods, and quantified carbon absorption effects using life cycle assessment models. Results demonstrate that although FRCAC exhibits 7.8%~14% reduced elastic modulus under the same-condition curing, pre-cambering completely compensates deformation discrepancies, satisfying structural requirements. While bending cracks increased by 8% and the crack length increased by 15%, the average width remained comparable to conventional concrete. Considering service-period carbon absorption, FRCAC beams achieved 7.69% reduction in net carbon emissions. This study pioneers engineering prototype validation of FRCAC's feasibility under actual load-environment coupling conditions. The findings are expected to advance the transformation of construction wastes from extensive landfilling to high-value utilization, providing a forward-looking solution for low-carbon structural engineering.

In recent years, global marine plastic waste pollution has become increasingly severe, posing a serious threat to marine ecosystems and human health, and it has become one of the urgent environmental issues of great concern. In China, a large coastal country, the prevention and management of marine plastic waste pollution is crucial for ensuring national marine ecological security. This study sorts out the main sources of marine plastic wastes in China, the migration characteristics of these wastes into the sea, and the current status of pollution prevention and control. It analyzes the major problems regarding environmental leakage, plastic outflow accounting, and key driving factor identification in the production, discharge, disposal, and recycling of plastics. Moreover, the study identifies the deficiencies in the monitoring, identification, interception, and disposal modes of marine plastic wastes in China, as well as the major challenges faced in the land‒sea integrated management, and further explores new types of marine plastic waste management modes, including plastic waste reduction at source, biodegradable product substitution, synergistic participation of multiple subjects of liability, and empowerment by artificial intelligence. Furthermore, the study suggests clarifying the key nodes for marine plastic waste governance, developing core technologies of intelligent regulation and resource utilization, and establishing a cross-sectoral collaborative management mechanism, thus to strengthen China's land‒sea integrated governance capacity in marine plastic waste pollution control, with a view to promoting the sustainable development of the marine environment and assisting in the construction of China's marine ecological civilization.

In recent years, China has demonstrated significant green development, with remarkable achievements in air pollution control evidenced by the sustained decline in annual average fine particulate matter (PM_2.5) concentration and continuous reduction of heavy pollution days. However, the structural and essential stress on air quality improvement remains prominent, as manifested by the increasing proportion of secondary components in PM_2.5 and the high-level fluctuations of ozone concentration, indicating that severe challenges remain in atmospheric environment governance in China and highlighting the urgent need to address multiple pressures, including multi-objective synergy, multi-pollutant collaborative control, and compliance with international environmental conventions. This study analyzes the current status of atmospheric environment governance in China, identifying prominent challenges including insufficient theoretical innovation in systematic atmospheric environment governance, urgent needs to harness the potential of synergistic effects from carbon-pollution co-governance, and the requirement for formulating multi-scale-integrated air-quality management strategies. Furthermore, it elucidates the intrinsic relationships among atmospheric environmental issues, particularly the interactions between regional and global atmospheric problems as well as the cross-sphere mechanisms of multi-pollutant, multi-media processes. A critical framework of systematic atmospheric environment governance is proposed, comprising fundamental theories and applications of atmospheric oxidation capacity, along with innovative technological chains of systematic environmental management. Strategic recommendations are outlined, including implementing top-level design for systematic governance, initiating scientific innovation programs for holistic pollution control, establishing coordinated management mechanisms, and deploying action plans. These measures aim to advance systematic air-quality management in China and enhance health risk prevention and ecological risk control capabilities in atmospheric environment governance.

As the manufacturing industry integrates deeply with the next-generation information technology and accelerates its transformation to intelligence, it is necessary to break the technical bottlenecks regarding industrial software development and high-end equipment manufacturing and establish an independent and controllable industrial Internet technology system to support the optimization of the entire process of intelligent manufacturing. This study analyzes the current status of intelligent manufacturing and industrial Internet, and presents an overall picture of the independent and controllable industrial Internet technology system for intelligent manufacturing from three aspects: industrial Internet technologies, intelligent manufacturing technologies based on industrial Internet, and independent and controllable software and hardware systems for industrial Internet. Moreover, this study summarizes the demonstrative applications of independent and controllable industrial Internet technologies for intelligent manufacturing, covering independent robotized intelligent manufacturing, industrial detection and perception based on independent and controllable industrial Internet, networked multi-robot collaboration for intelligent manufacturing, and multi-robot collaborative scheduling for intelligent manufacturing. The current challenges and technical directions of independent and controllable industrial Internet for intelligent manufacturing are also identified. Furthermore, it is proposed to actively apply technologies including the fifth-generation mobile communications, independent and controllable industrial software, cloud-edge-end collaboration of industrial Internet, robots equipped with domestic distributed operating systems, and independent and controllable multi-robot collaborative manufacturing. Meanwhile, it is necessary to accelerate the construction of an independent and controllable standards system to drive the integrated development of the industrial Internet and intelligent manufacturing, creating new paths for the upgrading and high-quality development of China's manufacturing industry.

Engineering sediment design is a common technical challenge faced by the water conservancy hubs in sediment-laden rivers worldwide. As a typical reservoir in the sediment-laden river, the Guxian Water Conservancy Project is a milestone project in improving the Yellow River water and sediment regulation system and implementing the national strategy of ecological protection and high-quality development of the Yellow River Basin. Proper handling of engineering sediment issues is crucial for the project development. On the basis of in-depth analysis of the design and regulation experiences from existing water conservancy projects in sediment-laden rivers such as Sanmenxia and Xiaolangdi Reservoir, this study focuses on the characteristics and changing trend of the incoming water and sediment of the Guxian Water Conservancy. In response to the design requirements in engineering sediment design, including the coupling design of long-term water and sediment series, active control of sedimentation morphology, and dynamic resilience maintenance of effective reservoir capacities, dynamic regulation is used as the guide of engineering sediment design. And several key technologies are developed, including the design of sediment-discharge bottom holes with ultra-deep and ultra-large discharge capacities, design of dynamic sediment erosion base level and capacity, coupling design between three sediment deposition patterns and dynamic storage capacity, and operation mode of storing clean water and regulating muddy flow. A water-sediment co-treatment technology system for sediment-laden rivers that features morphology control, process regulation, and dynamic response is formed. Moreover, the adaptability of Guxian Water Conservancy is improved to the extreme incoming water and sediment combinations, which is of great significance for enhancing the water-sediment regulation and water resource storage capacities of the Yellow River, and achieving the long-term stability in the lower reach of the Yellow River. Meanwhile, it provides a new technological paradigm for the treatment of engineering sediment problems in reservoirs of sediment-laden river.

The large-scale generation and accumulation of bulk industrial solid waste in China have significant ecological and environmental impacts. Therefore, strengthening the multi-level recycling of bulk industrial solid waste to reduce stock and minimize increment becomes crucial for ecological civilization and the construction of a Beautiful China. This study analyzes the prominent challenges faced by the comprehensive utilization of bulk industrial solid waste in China. Drawing on international advanced concepts and the current progress in circular economy research, it proposes a new concept of "Earth macro-cycle" and elaborates on its background and core elements. The study focuses on creating new paradigms in "Earth macro-cycle" research, including the reconstruction of bulk industrial solid waste through simulated natural mineralization and mine backfilling, transformation of bulk industrial solid waste into soil-like materials for ecological reuse, ecological balance and risk control of historically accumulated bulk industrial solid waste stockpiles, and intelligent decision-making and management system platform for the "Earth macro-cycle." By precisely applying the concept of "Earth macro-cycle," the study aims to build a circular green production model, establish an "Earth macro-cycle" model for hard-to-dispose industrial solid waste, and drive the creation of a circular society through systematic design. This will gradually enable the large-scale disposal and ecological return of bulk industrial solid waste.