ZnO Quantum dots with particle sizes about 5 nm were prepared by sol-gel method, the research about the photo luminescence(PL)/photoluminescence excitation(PLE) spectrum and the fluorescence lifetime indicated that the green emissions can be divided into two parts which were attributed to different transit mechanisms. The higher energy green emission was due to the electrons transit from conduction band to oxygen vacancies while the lower energy green emission was assigned to the electrons transit from the shallow donor levels which enhanced the green emission to the oxygen vacancies and the shallow donor levels was also the reason why the green emission reach strongest intensity when the excitation energy was a little lower than the band gap energy. While the blue emission can be explained by the electrons transiting from Zinc intervals to the valence band. The two mechanisms of green emission are first highlighted and should be considered in the optical application.
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Sci Rep
January 2025
Key Research Base of Philosophy and Social Sciences in Jiangsu Universities, Research Institute of Huai River Eco-economic Belt, Huaiyin Normal University, Huaian, 223300, China.
Carrying out carbon budget assessment and carbon compensation zoning research from inter-regional perspective can actively boost the formulation of green, low-carbon transformation strategies, guiding the flow of compensation credits, promoting regional equity and sustainable development, and realizing China's "dual-carbon" goal. Huai River Eco-economic Belt is considered to be a typical example of how land use affects carbon budget due to its more drastic land changes. The paper uses the carbon emission coefficient method to analyze the carbon revenue and expenditure of kinds of land-use patterns, and constructs the carbon compensation model with the help of the carbon budget concentration index and the dominant comparative advantage index, and puts forward the carbon compensation zoning program.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Zhejiang Provincial Engineering Research Center for Green and Low-carbon Dyeing & Finishing, Zhejiang Sci-Tech University, Hangzhou 310018, China; Zhejiang Provincial Innovation Center of Advanced Textile Technology, Shaoxing 312000, China. Electronic address:
Comparing to the solvent-based and waterborne polyurethanes (PU), the solvent-free reactive PU (RPU) is prepared via in-situ polymerization and film-formation of isocyanate-capped prepolymers and macromolecular polyols in solvent-free system. Thus, the carbon emissions and environmental pollutions are significantly reduced. However, the rapid polymerization also challenges the well control of structure and properties, especially the ordered microstructures.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
iBB-Institute for Bioengineering and Biosciences and i4HB-Institute for Health and Bioeconomy, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal; Bioengineering Department, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
A green approach towards the synthesis of both conventional and magnetic fluorescent powders for revealing latent fingerprints (FPs) is disclosed. The powders formulation is based on a biodegradable matrix and fluorescent dyes extracted from commercial felt-tip markers. Two classes of powders are described: one with a fluorescent component, and other with both fluorescent and magnetic components.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Institute of Blue and Green Development, Shandong University, Weihai, 264209, China; Faculty of Finance, City University of Macau, Macao, China. Electronic address:
Owing to critical policy significance, a growing body of literature has been predominantly concentrating on the social welfare benefits brought by green finance (GF) initiatives. However, there is a paucity of research that quantifies the economic costs of GF initiatives on carbon reduction, raising the increasing concerns about the irreconcilable climate-economy trade-offs. To end this, the present study systematically investigates the influence of GF initiatives on the carbon-related marginal abatement cost (MAC) using two competing hypotheses: regulatory versus technical effects.
View Article and Find Full Text PDFJ Environ Manage
January 2025
School of Geographical Science, Nanjing Normal University, Nanjing, 210023, China.
Urban agglomerations are central to global economic growth and the shift towards green development, particularly in developing countries. This study examines regional comparisons and variations in green development mechanisms within urban agglomerations to better understand their spatiotemporal patterns. An input-output indicator system was developed, accounting for social benefits and carbon emissions.
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