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Flow boiling stands out as an efficient mode of heat transfer with significant potential for reducing carbon footprint. Based on a coupled Volume-of-Fluid and Level Set (VOSET) method, this numerical study reveals the microlayer and its evaporative heat flux distributions, as well as the effects of microlayer evaporation and depletion on bubble dynamic behavior, flow pattern, wall superheat distribution, and boiling crisis for the flow boiling in a mini-channel. These aspects are firstly comprehensively reported by the numerical method. Results indicate that the rapid evaporation of a thin microlayer positioned beneath elongated bubbles significantly contributes to heat dissipation during flow boiling in a mini-channel. The heat flux through the microlayer surpasses 300 kW/m2, accounting for approximately 42% of heat dissipation at 200 kW/m2. Furthermore, this contribution increases to over 70% as the heat flux exceeds 500 kW/m2. As a result, in comparison to scenarios without microlayers, the presence of microlayers results in an average heat transfer coefficient (HTC) that is 3.97 times larger within the range of 200–500 kW/m2. Additionally, microlayer evaporation delays the happening of flow boiling crisis. Without microlayers, the wall superheat exceeds 180 K at 500 kW/m2, whereas under microlayer influence, the maximum local wall superheat is only 37.09 K at 1000 kW/m2. With further increases in heat flux, the emergence of large dry patches resulting from microlayer depletion induces the beginning of heat transfer deterioration. Finally, the ongoing coalescence of elongated bubbles necessitates a prolonged period for rewetting dry patches at the exit of the mini-channel, triggering the flow boiling crisis at 1300 kW/m2. The study results provide crucial guidance for the development and application of the flow boiling heat transfer technology for the thermal management of data centers. [ABSTRACT FROM AUTHOR]

China has committed to enhancing its national efforts to peak CO 2 emissions by 2030. Rather than applying broad emission reduction measures nationwide, a more efficient strategy involves focusing on select provinces and sectors as pioneers in emission reduction. This targeted approach is expected to drive broader, nationwide progress towards the carbon emission reduction goal, thereby improving the effectiveness of emission reduction policies. This study integrates complex network control theory with input–output modeling to develop a detailed analysis of the embodied carbon emission (EC) transfer network at the province-sector level in China for the year 2017. By examining the network's characteristics and identifying key nodes for control, the study arrives at several notable findings: (1) EC transfers predominantly flow from central and northern provinces to the economically vibrant southeast provinces, and from energy-intensive sectors towards services, manufacturing, and others. (2) The network's structure follows a scale-free distribution, indicating that a limited number of provincial sectors are central to the network, managing a majority of EC transfers and thus playing a crucial role. (3) Utilizing complex network control theory, an algorithm was developed to identify optimal control nodes, aiming to minimize the costs associated with emission reduction. This approach identified 287 provincial sectors, about one-third of the total, while keeping abatement costs below one-fourth of potential expenses. (4) The identified crucial control nodes consist of approximately 38% source nodes and 20% isolated nodes. Sectors downstream of these source nodes, such as sec04, sec05, and sec22, show significant node strength and betweenness centrality, enhancing the spread of emission reduction impacts. (5) When compared to other node selection strategies, the algorithm not only achieves complete network control but also minimizes abatement costs effectively. This research offers valuable insights for policymakers on the dynamics of interregional trade and EC management. It supports the formulation of a strategic, long-term plan for collaborative emission reduction across provinces and sectors, aligning with China's environmental commitments. [Display omitted] [ABSTRACT FROM AUTHOR]

The escalating demand for resources in urban and rural construction development raises the crucial question of achieving green development within limited resource constraints. This study delves into the interplay between environmental policy and green development in urban and rural construction. Utilizing the spatial Durbin model for analysis, findings reveal that investment-oriented environmental regulation significantly impacts green development and positive spillover effects in neighboring regions when considering spatial weight matrices. In contrast, cost-based environmental regulations positively affect green development when spatial interactions are disregarded. However, they exhibit negative effects at the spatial level, potentially leading to a "pollution relocation" phenomenon. Although the influence of R& D subsidy-based environmental regulations on green development is not significant, their impact becomes notable upon considering spatial interactions, potentially generating positive effects across regions through mechanisms such as technology diffusion and knowledge transfer. Furthermore, from an endogeneity perspective, the impact of environmental regulatory tools on green development exhibits a time lag effect. Moreover, investment-type regulation in the eastern regions significantly fosters green development, whereas cost-based regulation shows a suppressive effect; investment-type regulation in central regions has a positive spillover on neighboring areas; and R&D subsidies in western regions negatively impact local green development. Moreover, the quality of governmental institutions, market integration, and technological innovation are key factors influencing green development in China's urban and rural construction. This study reveals the direct and indirect effects of various environmental policy tools on green development in urban and rural areas. It emphasizes the importance of considering spatial interactions in implementing environmental policies, providing a theoretical foundation and practical guidance for optimizing environmental policies. [ABSTRACT FROM AUTHOR]

Although briquetting is an appropriate technology for the production of renewable energy, its widespreadness in Southeast Asia is limited. Especially due to the high initial investments and energy consumption of a high-pressure briquetting press. However, manual low-pressure briquetting presses (operating pressure <5 MPa) can represent a relevant alternative, regarding to their ease of use and modest energy consumption. The aim of the present research was to develop and verify a manual wooden low pressure briquetting press with a square-shaped pressing chamber, piston and a single lever as a pressing unit. In practice, press was designed, manufactured, and verified by successful bio-briquette samples production. Four different feedstock mixtures were prepared from coconut mesocarp fibre (CF), bamboo skin (BS), pineapple leaves (PL), sugarcane bagasse (SB); each mixed with external binding agent (wastepaper) in biomass:binder ratios of 1:1 and 2:1. The achieved bulk density ρ ranged from 204.30 ± 15.73 kg m−3 for 1:1 feedstock mixtures and 199.31 ± 23.13 kg m−3 for 2:1 feedstock mixtures. The press efficiency, feasibility and practicability were positively evaluated within their possible utilisation in rural areas of developing countries. The importance of research increases constantly due to the worldwide need for a transition from fossil fuels to renewable energy sources, proper waste management, and reduction of environmental and health risks related to improper treatment of waste materials. The final idea of the article contributes to the development of the sector of clean green energy production, simultaneously with raising awareness about sustainable technologies for proper waste management within the wide public. [Display omitted] [ABSTRACT FROM AUTHOR]

The common ground of both critics and proponents of green productivity is arguably hinged on the main role of environmental technological advancement. Considering the drive for climate-neutral economy among the Nordic states, the current study examines the role of climate change technological development within the countries and technological spillovers across countries in the pursuit for green economy. By using a combination of pooled mean group approach of autoregressive distributed lag (for coefficient estimation) and the recently developed Granger non-causality approach by Juodis et al. (2021) for the panel dataset analysis over the period 1990–2018, the results reveal that both domestic technological development and spillovers from abroad promote long-run green productivity growth in the panel and country-specific estimations. In both estimations, the impact of international diffusion of climate change technologies on green productivity is found to be larger. Additionally, the influence of these two dynamics of climate change-related technologies on attaining greening economy is the most impactful in Sweden. In the remaining Nordic economies, climate change technology spillovers in Denmark are more impactful than in Finland and least in Norway, while climate change technological development in Norway drives green productivity more than in Finland and least in Denmark. As a robust insight, the Granger causality techniques revealed causality from climate change technologies within the countries, climate change technology spillovers, and population to green productivity. Consequently, public policies should promote green innovativeness and especially learning and knowledge transfer from other countries to achieve climate neutrality targets. • The drivers of green productivity in the Nordic countries are investigated. • Domestic and foreign spillovers of green technology promote green productivity. • Green productivity responds more strongly to foreign technology spillovers. • The impact of climate change-related technologies is the highest in Sweden. • Financial development and population also drive green productivity. [ABSTRACT FROM AUTHOR]

The innovation performance of Chinese wind power enterprises has not been effectively improved, which may be caused by the behavior of enterprises using the information asymmetry between government and enterprises to camouflage R & D and obtain policies incentives. Therefore, this paper attempts to construct an evolutionary game model of tax incentives in complex network, introduces technology spillover and reputation cost, and discusses the diffusion of R & D in Chinese wind power industry. The results show that: (1) Reducing technology spillover not only contributes to the R & D diffusion, but also reduces the peak in the proportion of enterprises with camouflaging R & D. (2) Increasing reputation cost of violations can accelerate enterprises to reach the equilibrium and reduce the time that the proportion of the behavior with camouflaging R & D decreases. (3) The increase in incentives of lower tax rate for high-tech enterprises will create "lowland effect" for high-tech enterprises. And the increase in incentives of extra deduction for R & D expenses will increase the R & D diffusion of non-high-tech enterprises, while also suppressing the peak of the proportion in non-high-tech enterprises with camouflaging R & D. [ABSTRACT FROM AUTHOR]