The enhancement of the performance of advanced nitride-based optoelectronic devices requires the fine tuning of their composition, which has to be determined with a high accuracy and at the nanometer scale. For that purpose, we have evaluated and compared energy dispersive X-ray spectroscopy (EDX) in a scanning transmission electron microscope (STEM) and atom probe tomography (APT) in terms of composition analysis of AlGaN/GaN multilayers. Both techniques give comparable results with a composition accuracy better than 0.6 % even for layers as thin as 3 nm. In case of EDX, we show the relevance of correcting the X-ray absorption by simultaneous determination of the mass thickness and chemical composition at each point of the analysis. Limitations of both techniques are discussed when applied to specimens with different geometries or compositions.
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http://dx.doi.org/10.1186/s11671-016-1668-2 | DOI Listing |
J Environ Manage
December 2024
Institute of Rural Management Anand, Gujarat, India. Electronic address:
India's progress vis-à-vis the United Nations' Sustainable Development Goals (SDG) has stagnated since 2020. The consequences of the non-attainment of the SDGs can be severe. Therefore, questions arise as to what steps must be taken to accelerate progress in India's SDG attainment.
View Article and Find Full Text PDFJ Environ Manage
December 2024
College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266520, China.
The disposal of municipal solid waste (MSW) is a significant source of greenhouse gas (GHG) emissions. As incineration becomes the primary method of MSW disposal in China, MSW incineration (MSWI) plants are expected to play a crucial role in mitigating GHG emissions in the waste sector. This study estimated the quarterly GHG emissions from two representative MSWI plants in Qingdao using a life-cycle assessment (LCA) approach.
View Article and Find Full Text PDFInorg Chem
December 2024
Laboratory of Complex Heterostructures and Multifunctional Materials, National Institute of Materials Physics, Atomistilor 405A, Magurele 077125, Romania.
CuZnSnSe (CZTSe) is a promising material for thin-film solar cells due to its suitable band gap, high absorption coefficient, and composition of earth-abundant and nontoxic elements. In this study, we prepared CZTSe thin films from Cu/SnSe and ZnSe stacks using a two-step annealing process. Initially, Cu-Sn-Se (CTSe) films were synthesized by sequential deposition and annealing of Cu and SnSe precursors in either a selenium (Se) or tin-selenium (Sn+Se) atmosphere.
View Article and Find Full Text PDFHum Reprod
December 2024
Department of Medical BioSciences, Radboudumc, Nijmegen, The Netherlands.
Study Question: How can we best achieve tissue segmentation and cell counting of multichannel-stained endometriosis sections to understand tissue composition?
Summary Answer: A combination of a machine learning-based tissue analysis software for tissue segmentation and a deep learning-based algorithm for segmentation-independent cell identification shows strong performance on the automated histological analysis of endometriosis sections.
What Is Known Already: Endometriosis is characterized by the complex interplay of various cell types and exhibits great variation between patients and endometriosis subtypes.
Study Design, Size, Duration: Endometriosis tissue samples of eight patients of different subtypes were obtained during surgery.
Land use conversion from natural forests to grassland, plantation forests, mono-cropping coffee and croplands is a significant causes of soil degradation, leading to aggravate soil acidity and nutrient depletion. However, there is limited information regarding comprehensive effect of land use conversion on soil fertility and acidity in western Oromia Region of Ethiopia. Hence, this study aims to assess the surface soil fertility and acidity across different land use types (forest, crop, eucalyptus land, grazing land, and coffee farmland) to provide management options.
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