Mahmood Golzarian

Luminescent solar concentrators (LSCs) utilizing carbon dots (CDs) have emerged as promising solutions for transparent photovoltaic applications due to their high transparency and efficient light-to-electricity conversion. This study investigates the synthesis and optical enhancement of CDs doped with transition metal ions-cobalt, nickel, copper, and zinc-to improve LSC performance. Using a microwave synthesis method, we produced CDs with a high quantum yield of 81%, a substantial Stokes shift of 0.71 eV, and excellent stability. Doping CDs with metal ions at molar concentrations of 1%, 3%, and 5% revealed that 1 mol% copper-doped CDs exhibited superior optical properties, enhancing light absorption and emission through effective metal-ion interactions. LSCs, fabricated with dimensions of 15 x 15 x 0.6 cm3 using glass and PMMA waveguides, achieved notable photovoltaic performance with an optical efficiency of 3.99% and a photoconversion efficiency (PCE) of 1.45% for PMMA-based devices. The introduction of copper at 1% concentration resulted in a 22% increase in both optical efficiency and PCE. Stability assessments over 90 days indicated minimal performance degradation, underscoring the robustness of the synthesized materials. This research highlights the potential of metal-doped CDs to optimize LSC technology, facilitating integration into urban environments and advancing the commercialization of transparent photovoltaic systems.

Turfgrasses are essential landscape plants with social, environmental, and aesthetic services for urban ecosystems. However, more is needed to know how to establish them so that they can benefit from their ecosystem services in urban environments. This research examined some quality and morphological and physiological factors for the establishment and social and environmental service assessment of three warm-season turfgrasses, including Kikuyu grass (Pennisetum clandestinum), bermuda grass (Cynodon dactylon), and buffalo grass (Buchloe dactyloides), compared to the cool-season grass of tall fescue (Festuca arundinacea Schreb.). The experiment was split-plot in time, based on a randomized complete block design with eight replications. The main plot was the season with four levels, and the subplot was the four turfgrass species types. The results indicated that seasons and turfgrass types and their interaction significantly impacted most measured variables (p ≤ 0.01). Some quality measurements like turf density, color, texture, coverage, and quality after clipping and establishment confirmed the superiority of Buchloe dactyloides over the other species. Also, kikuyu grass showed higher turfgrass density, more potential for weed control, and higher coverage and growth rate but also showed invasiveness features. Tall fescue had the lowest visual aesthetic compared with the other turfgrass species. Warm-season turfgrasses adaptable to the ecology of the region should be used compared to tall fescue to achieve better turfgrass quality and social and ecosystem services for the sustainable development of arid urban environments.

Besides the importance of internal quality, the textural quality properties of the product have a remarkable effect on consumer satisfaction and market price. Mainly, the three-dimensional (3D) modeling technique is applied to evaluate the quality of agricultural products. This study aimed to employ the structure from motion (SFM) method along with the particle film technique to predict the physical features of tomatoes. Reconstructing 3D models of tomatoes is challenging due to their shiny skin. In this study, a new method based on particle films was developed to address this issue. Fifty samples of tomatoes were randomly selected with various sizes and four ripeness levels with no-external damage. The SFM technique applied with kaolin particle film was a suitable approach for assessing the surface area, volume, and color index, with a correlation coefficient of 0.76, 0.88, and 0.67, respectively. Also, 3D model predictions achieved these textural properties by obtaining RMSEs of 2.44, 2.30, and 0.35, respectively. Finally, the proposed SFM method’s results showed an error of less than 5%. This technique has proven to be a cable technique for the 3D reconstruction of products with a glossy surface.