A microwave combustion method was used to synthesize Cu1-xZnxFe2O4 (x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5) nanoparticles. The synthesized Zn-doped CuFe2O4 nanoparticles were characterized by techniques ...such as X-ray diffraction, high-resolution scanning electron microscopy, UV–visible diffuse reflectance spectroscopy, photoluminescence spectroscopy, Fourier transform IR spectroscopy, and vibrating sample magnetometry. X-ray diffraction and Fourier transform IR spectroscopy results confirmed the formation of Cu1-xZnxFe2O4(x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) nanoparticles. The crystallite size and lattice parameter were determined as 15–19 nm and 8.319–8.400 Å, respectively. High-resolution scanning electron microscopy revealed the presence of agglomerated spherical particles of Cu1-xZnxFe2O4. Elemental mapping of pure and Zn-doped CuFe2O4 was done by energy-dispersive X-ray analysis. The band gap was calculated with the Kubelka-Munk function and was found to lie in the range from 2.30 to 2.51 eV. Finally, M-H curves were plotted and the magnetic properties, such as coercivity, remanent magnetization, and saturation magnetization, were determined.
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•Zinc-doped copper ferrite was synthesized by a microwave combustion method.•Structural, morphological, optical, vibrational, and magnetic properties are studied.•Zinc-doped copper ferrite nanoparticles exhibit ferromagnetic behavior.
In the present article, the pure PbS and different concentrations of Gd doped PbS (Gd:PbS) films were developed using the spray pyrolysis route by growing thin films on the glass substrate. The ...estimated crystallite sizes were found from 15.5 to 20.8 nm for as-deposited films. The spherical shape morphology of grains was observed by FESEM. The obtained average grain sizes varied from 52.8 to 108.2 nm were obtained from the grain size distributions for 0.0, 0.5, 1.5, and 2.5 wt % Gd: PbS films, respectively. Extinction coefficients of as-deposited films were measured from 0.04 to 0.12 in the range of wavelength 200–2500 nm. Refractive indices of films were obtained from 5.4 to 1.22 in range of 200–2500 nm wavelength. The band gaps of 2.75, 2.64, 2.45, and 3.10 eV for 0.0, 0.5, 1.0 and 2.5 wt % Gd thin films were estimated using Tauc's relation respectively. The values of the dielectric constant, dielectric loss, and optical conductivity were recorded in the range of 1.32–29.6, 0.30–0.61, and 2.34 × 1014–3.08 × 1013 between 200 and 2500 nm wavelengths for as-deposited thin films respectively. The optimum values of linear susceptibility, non-linear susceptibility and refractive index were recorded in the range of 1.23–2.93, 5.21 × 10−10 - 120 × 10−10, 3.54 × 10−9 – 74.2 × 10−9 (esu) between 1.46 and 0.52 eV respectively for as-deposited thin films. The Gd: PbS thin films improve the physical properties and therefore, it becomes suitable candidature for the applications in optoelectronic devices.
•Fabrication of PbS and Gd:PbS films on glass by nebulizer spray pyrolysis is reported.•Spherical grains with highly packed structure of PbS and Gd:PbS thin films.•Homogeneous doping of Gd in ZnO was detected by EDX/SEM mapping.•The band gaps is noticed in range of 2.45–3.10 eV for PbS and Gd:PbS thin films.•Values of linear/non-linear susceptibilities, and non-linear refractive index of Gd: PbS decreases as compared to pure.
This paper examines the urban character of Chinatown districts around the world, as a key example of an urban ethnic enclave, focusing on four large Chinatowns in San Francisco, Yokohama, Melbourne ...and Sydney. It advances knowledge about the spatial elements that define urban districts, a concept pioneered by Kevin Lynch. Existing literature on Chinatowns primarily explores the historically changing relationships between their Chinese migrant communities and their host cities, or the visual and physical character of individual cases. This paper develops new insights into how the built forms of these urban districts are similar to or different from their surroundings and from each other. It employs a methodology that combines space syntax analysis of street networks, morphological analysis of built form, land-use analysis, and mapping of visual character from street level. It examines the Chinatown districts' spatial extents in terms of contrasts between their spatial attributes and their wider urban surroundings. The findings develop a new taxonomy of Chinatowns based on their urban spatial characteristics.
•Develops new methods to map and analyse the spatial character of urban districts•Compares Chinatowns' built form and street networks to their urban surroundings•Analyses Chinatowns' varying accessibility within the overall urban street network•Reveals how contemporary Chinatowns extend beyond their traditional boundaries•Compares four case study cities to identify a new spatial taxonomy of Chinatowns
•We evaluate the relation of morphological awareness and reading comprehension.•Four potential mediators are proposed are tested in structural equation modeling.•Morphological awareness contributes ...directly and indirectly to reading comprehension.•Morphological decoding and morphological analysis are distinct indirect pathways.•Our findings inform on the mechanisms underlying the relation in children.
The relation between morphological awareness—defined as the awareness of and ability to manipulate the smallest units of meaning in language—and reading comprehension remains in need of specification. In this study, we evaluated four potential intervening variables through which morphological awareness may contribute indirectly to reading comprehension. We assessed word reading and vocabulary as well as children’s ability to read and analyze the meaning of morphologically complex words (morphological decoding and morphological analysis, respectively). Controls of phonological awareness and nonverbal ability were included in the model. Participants were 221 English-speaking children in Grade 3. Multivariate path analyses revealed evidence of two indirect relations and one direct relation between morphological awareness and reading comprehension. In the first indirect path, morphological awareness contributed to morphological decoding, which then influenced word reading and finally reading comprehension. In a second indirect path, morphological awareness contributed to morphological analysis, which contributed to reading comprehension. Finally, in a direct path, morphological awareness contributed to reading comprehension beyond all other variables. These findings inform as to the potential mechanisms underlying the relation between morphological awareness and reading comprehension in children.
•SF-GRAC was prepared, which showed improved mechanical properties compared to recycled aggregate concrete.•Steel fiber can significantly improve the mechanical property of SF-GRAC, especially for ...ductility and toughness.•SF-GRAC reduced about 26% of carbon emission without any mechanical property deterioration compared to OPC concrete.
Steel fiber-reinforced geopolymeric recycled aggregate concrete (SF-GRAC) was proposed as a high-performance green concrete, and the mechanical properties were investigated experimentally to promote the use of SF-GRAC in structural engineering. A series of SF-GRAC specimens were prepared with different contents of steel fibers and recycled aggregates, and compression tests, splitting tensile tests and four-point flexural tests were conducted. Meanwhile, the microstructure was observed through scanning electron microscope (SEM) for the interfacial transition zones (ITZ) between the geopolymeric matrix and the recycled aggregates or steel fibers. The results showed that the compressive, tensile and flexural strength of recycled aggregate concrete obviously increased when the original Portland cement (OPC) was replaced with ground granulated blast furnace slag-fly ash based geopolymer, but the ductility and toughness also decreased. By adding up to 1.5% steel fibers, the compressive, tensile and flexural behavior of SF-GRAC were obviously improved, and more premium than OPC concrete with natural aggregates, which made it eligible for structural application. SF-GRAC with 100% recycled aggregate and 1.5% steel fibers had 38% higher compressive strength, 83% higher tensile strength, and 41% higher flexural strength than OPC concrete with natural aggregates, while the compressive and flexural toughness indexes increased over 160% and 170% respectively. Micro morphological analyses illustrated that the microstructure of geopolymeric matrix was denser and more uniform than OPC matrix, and there was no obvious cracks and pores in the ITZs of geopolymeric matrix-aggregate and geopolymeric matrix-steel fiber, indicating a good bonding behavior. Through data-fitting, a series of regression models were proposed to predict the elastic modulus, splitting tensile strength and flexural strength of SF-GRAC, which fit reasonably well with the experimental results. Carbon emission analysis was also conducted on SF-GRAC, which was proven to be a green construction material with over 26% reduction on carbon emission compared to OPC concrete.
Despite the preventive measures taken by the WHO, childhood obesity is still on the rise and is expected to increase by 100% between 2020 and 2035. Food marketing continues to permeate children's ...environments in numerous ways and influence the food behaviour of children, thus significantly contributing to the rise of obesity. Studies suggest that the literature on the effects of food marketing on children is complex and multidimensional. To fully understand these effects, a comprehensive and systematic approach is required. Nonetheless, existing reviews have focused only on specific aspects and have not comprehensively covered the literature on food marketing to children. Therefore, this review aims to navigate potential research gaps in the existing literature through a comprehensive examination of the literature by using morphological analysis (MA) methodology, the first time in this domain. Using PRISMA, 202 papers were considered eligible for inclusion and further analysed using MA. The articles were categorised into three dimensions to develop the MA framework: Stimuli (Food well-being), Organism, and Response, and 34 variants. The review has presented future research prospects by identifying at least 218 research gaps. With these findings, researchers can further explore the gaps and develop new research questions that could foster an understanding of the multifarious literature. Moreover, these findings can also provide marketers and practitioners with a better comprehension of the current state of the literature and develop more effective strategies for responsible marketing practices and policies.
Nanoporous gold (np-Au) differs from its macroporous counterparts through its ligament and pore length scales, its high relative density, and its very distinct mesoscale cellular architecture. When ...reexamining the applicability of conventional macroporous foam scaling laws to np-Au, difficulties persist not only in determining the solid properties of nanoscale ligaments, but also because np-Au structure is not self-similar as the relative density changes. Thus, a clear distinction of the effects of relative density and structure is required. This paper aims to capture the role of topology and morphology into the scaling laws by comparing the overall mechanical response of real np-Au structures with the behavior of spinodal and gyroid structures. Quantitative morphological and topological characterization of these structures has been carried out and their role on the macroscopic elastoplastic response of np-Au has been studied using finite element (FE) simulations. The predicted elastic modulus of real np-Au structures from FE simulations is in remarkable agreement with the nanoindentation measurements, and validates the numerical simulations. Quantitative structural analysis reveals that np-Au and spinodal structures are topologically very distinct, but similar in their morphology. On the other hand, gyroids are both morphologically and topologically very distinct from np-Au. The results suggest that the macroscopic stiffness and strength are highly sensitive to the topology, while being relatively much less sensitive to the morphology. The effects of structural topology are captured into modified scaling laws where the geometric pre-factors for the stiffness and strength are found to vary linearly with the scaled genus.
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•Synthesis of Silver Nanoparticles (AgNPs) was reported utilizing AgNO3 as precursor and PVP as stabilizing agent in ethylene glycol.•Effect of concentration ratios of AgNO3 and PVP ...was examined on the morphology and size of AgNPs.•AgNPs were evaluated for their size dependent photocatalytic and antibacterial potential.•Small size AgNPs having high energy band gap exhibited improved photocatalytic potential for degradation of MB dye following pseudo first order kinetics.•AgNPs were found more active against gram-negative strains of bacteria.
Organic dyes present in the effluents of paints, and textile industries are posing major environmental threats. Rapid decomposition of these dyes using non-toxic, renewable and cost-effective silver nanoparticles (AgNPs) is a pragmatic strategy. Therefore, in current research work, AgNPs with different size ranges have been prepared following the polyol reduction method by controlled exploitation of substrate/reducing agent molar ratio and pH of reaction media. AgNPs have been characterized by UV–Visible spectroscopy, Scanning Electron Microscope (SEM), Powder X-Ray Diffraction (XRD) and Energy Dispersive X-ray spectroscopy (EDS). Absorption peaks ranging from 420 to 465 nm confirmed the synthesis of AgNPs using surface plasmon resonance (SPR) bands. The increase in molar ratio and pH led to the blue shift in absorption bands which revealed the size reduction of AgNPs. XRD analysis confirmed the crystallite size (16–21 nm) and Face centered cubic (FCC) crystalline structure of AgNPs. EDS was utilized to check the purity of AgNPs. SEM confirmed the spherical morphology of AgNPs with a size range between 70 and 110 nm. The energy band gap was determined using the Tauc plot equation to correlate the catalytic properties of NPs with size. Different-sized AgNPs were utilized as photocatalysts for the degradation of Methylene blue (MB) dye under sunlight irradiation. AgNPs having an average size of 70 nm showed improved photocatalytic potential by 94% degradation of MB in 80 min. The AgNPs were also evaluated for their antibacterial activities against gram-positive and gram-negative strains of bacteria. Small-size AgNPs were found more active against gram-negative strains of bacteria.
Introduction We examine how awareness and analysis of morphemes contribute to children's reading comprehension and its development. A multidimensional perspective on reading comprehension posits ...morphological awareness and morphological analysis play distinct roles in reading comprehension. Assuming individual differences in growth in these aspects of morphological processing, their concurrent influences can vary depending on children's reading comprehension abilities, and predictive influences can change as children's reading comprehension abilities improve. Method The current longitudinal study examined the concurrent and predictive influences of awareness and analysis on children's reading comprehension from Grades 1 to 3. Data from 171 public school children, with diverse reading comprehension abilities, were collected across five waves and were analyzed using cross-lagged panel structural equation modeling. Results Results showed concurrent relationships among morphological awareness, analysis, and reading comprehension in Grades 1 and 2, and morphological analysis having a concurrent relationship with reading comprehension at the end of Grade 3. Morphological awareness in all waves but Wave 3, at the end of Grade 2, predicted subsequent reading comprehension. Morphological analysis did not predict subsequent reading comprehension. Discussion Findings support the multidimensional conceptualization of awareness and analysis as distinct morphological processes that play early-wave concurrent and across-wave predictive roles in children's reading comprehension development.
