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Development of iron oxide based-upconversion nanocomposites for cancer therapeutics treatment
No full textAdministration of therapeutic strategies alongside magnetic multifunctional nanocomposites has displayed improved cancer prognosis. However, the clinical use of this combination is limited owing to poor bioimaging performance, low biocompatibility, restricted tissue penetration in ultraviolet/visible regions, and low therapeutic efficacy of nanocomposites. To overcome these existing challenges, we designed iron oxide (Fe3O4)-based upconversion nanoparticles (UCNPs). Fe3O4 nanoparticles were synthesized via facile solvothermal method and incorporated into mesoporous silica (mS) layer (Fe3O4@mS). Fe3O4@mS nanoparticles were further decorated onto the surface of the UCNPs as a core material (UCNP-Fe3O4@mS, FMUP). Methotrexate (MTX) an efficient anticancer drug was loaded onto the mesoporous silica to produce FMUP-MTX nanocomposite. The FMUP nanocomposite displayed excellent photothermal therapy and showed 43% photothermal conversion efficiency. The designed nanocomposite has ability to decompose H2O2 to generates hydroxyl radical that promote chemodynamic therapy effect due to attribution of Fenton reaction. FMUP-MTX nanocomposite possessed improved chemotherapeutic performance under NIR laser irradiation. Further, T2-weighted magnetic resonance imaging performance of nanocomposite was observed. In vitro studies shown that cell viability was decreased to 25% under laser irradiation due to the therapeutic effect. In vivo studies exhibited that the FMUP-MTX nanocomposite inhibited the tumor growth with the laser irradiation. Therefore, these nanocomposites can be considered as a promising candidate for cancer therapeutics treatment
Maturity model for early-age compressive strength estimation of fly ash concrete considering the effect of temperature
No full textThe significant effect of temperature on the early-age compressive strength development of fly ash concrete was investigated through experimental study and modeling calculations in this paper. The compressive strengths of concrete specimens with different fly ash to binder ratios, cured at three different temperatures, were tested at various ages. The experimental results demonstrate a significant difference in strength development between ordinary concrete and fly ash concrete, indicating that the existing maturity model for normal concrete is unsuitable for predicting the compressive strength of fly ash concrete. To further quantitatively analyze the effect, the maturity model, which takes into account the different curing temperature histories for fly ash concrete, was modified by reevaluating the coefficient s with reference to the fib Model Code 2010. This modification allows for the real-time prediction of compressive strength development based on regression analysis of experimental data obtained in this study. The results indicate that, compared to the original strength function, the compressive strength of fly ash concrete predicted by the modified maturity model is more accurate, demonstrating that the modified model can effectively monitor and predict the real-time compressive strength of fly ash concrete at construction sites
Transforming Chiller Plant Efficiency with SC+BAS: Case Study in a Hong Kong Shopping Mall
Full text linkThe imperative for building managers, in the face of high-density urban environments, is to drive existing chiller plants to greater operational efficiency through the application of advanced technological interventions. The case for applying Supervisory Control (SC) and a Building Automation System (SC+BAS) for optimizing chiller plants is the subject of investigation here, through the lens of a typical commercial shopping mall in the highdensity infrastructure of Hong Kong. The application of SC+BAS falls into the realm of advanced Trim/Respond algorithms coupled with sophisticated sequencing algorithms that allow for refined optimization of the chiller operations in response to the dynamic demands of urban infrastructure. The SC+BAS features an array of optimizations specifically for the chiller plant. Incentive parameters such as cooling capacity, energy usage, and Coefficient of Performance (COP) were thoroughly studied through 12 months’ worth of data, before and after the implementation of the SC+BAS. Empirical observations indicate a statistically significant 17.6% energy usage decrease, coupled with a 15.3% decrease in the related energy expenditure costs. Furthermore, the environmental impact is calculated, with an estimated 61.1 tons reduction in the amount of CO2 emissions, hence emphasizing the capacity for SC+BAS in offsetting the carbon footprint for commercial buildings. These data prove convincingly that the implementation of SC+BAS can increase the energy efficiency in chiller plants in commercial buildings, supporting the overall sustainability of the urban infrastructure. In turn, the authors suggest other areas for optimization through the advanced sequencing of chillers and demand-based cooling strategies. This highlights the ability of SC+BAS in creating more economical and green building operations regarding urban microclimates, occupant behavior patterns, and interactivity with the power grid, leading ultimately to the holistic optimization of chiller plant performance within the urban framework
