Unveiling the photocatalytic marvels:Recent advances in solar heterojunctions for environmental remediation and energy harvesting

In the quest for effective solutions to address Environ.Pollut.and meet the escalating energy demands,heterojunction photocatalysts have emerged as a captivating and versatile technology.These photocatalysts have garnered significant interest due to their wideranging applications,including wastewater treatment,air purification,CO_(2) capture,and hydrogen generation via water splitting.This technique harnesses the power of semiconductors,which are activated under light illumination,providing the necessary energy for catalytic reactions.With visible light constituting a substantial portion(46%)of the solar spectrum,the development of visible-light-driven semiconductors has become imperative.Heterojunction photocatalysts offer a promising strategy to overcome the limitations associated with activating semiconductors under visible light.In this comprehensive review,we present the recent advancements in the field of photocatalytic degradation of contaminants across diverse media,as well as the remarkable progress made in renewable energy production.Moreover,we delve into the crucial role played by various operating parameters in influencing the photocatalytic performance of heterojunction systems.Finally,we address emerging challenges and propose novel perspectives to provide valuable insights for future advancements in this dynamic research domain.By unraveling the potential of heterojunction photocatalysts,this reviewcontributes to the broader understanding of their applications and paves the way for exciting avenues of exploration and innovation.

Particles in a circulation loop for solar energy capture and storage

This study defines and assesses the selection ciiteria for suitable particulate materials to be used in an upflow bubbling fluidized bed (UBFB) or dense up-flow powder circulation system for solar energy capture and storage. The main criteria identified are based on the thermophysical and thermomechanical properties, attrition behavior, and the considerations of health and environmental hazards of the candidate powders. Finally, a cost comparison and tentative ranking of the different can didate powders is presented in addition to a weighted scoring. Significant scoring differences can be observed between the various materials. Olivine possesses the most favorable characteristics and appears to be the particulate material of choice for solid/gas suspension heat transfer fluids.

A new design approach for the established flow region of vertical,dilute-phase pneumatic conveyors

An analysis has been completed for a comprehensive set of vertical,dilute-phase pneumatic conveying pressure drop data from an investigation by Flatow.The data were collected in the established flow region for eight different materials conveyed in 0.05-,0.10-,0.20-m internal diameter,20-m tall steel risers.Particle velocities derived from the pressure drop data were used to develop an equation of motion that includes terms for pipe diameter,terminal velocity,coefficient of restitution,and particle shape.The best data fit was achieved using the actual gas density and the actual gas velocity adjusted for voidage.Adjusting the terminal velocity for voidage,an approach recommended by many investigators,did not improve the fit for reasons identified by the present research.Using the equation of motion,particle velocities were predicted and used to calculate total pressure drops that are within±15%of the measured values.The calculated values also produce the characteristic trough-shaped total pressure drop curves allowing the minimum pressure drop gas velocity to be determined without recourse to a separate correlation.A comparison with other studies using shorter risers indicates that data from these studies likely include acceleration effects.A separate study will investigate this observation further.

ACHIEVING THE NET-ZERO-ENERGY-BUILDINGS “2020 AND 2030 TARGETS” WITH THE SUPPORT OF PARAMETRIC 3-D/4-D BIM DESIGN TOOLS

INTRODUCTION The level of man-made CO_(2) emissions worldwide climbed to a new record of 30 billion tons in 2010.In 2011,at the COP17 U.N.Climate Change Conference in Durban,South Africa,high-ranking representatives from around the world met again to discuss solutions.For the building sector,numerous energy-efficiency market changes and benchmarking resolutions,like the mandatory E.U.“nearly Net-Zero-Energy-Building(NET-ZEB’s)2018 and 2020 regulations”for all new public and privately owned buildings are now set up to help minimizing carbon emissions and reverse the negative impact.1 In the United States,the American Institute of Architects(AIA)adopted the 2030 Challenge as a voluntary program,where participating buildings aim to achieve a 90%fossil fuel reduction by 2025,and carbon-neutrality by 2030.2 To accomplish these energy goals,designers must strive to best design and utilize the resources available on a site.However,are these goals of achieving carbon-neutral buildings possible?How can NET-ZEB’s become the curricular standard and practical routine in education and the profession?To date,the basic curricular design process components with integrated project delivery metrics for a robust 3-D/4-D-net-zero regulatory design framework are either incomplete or missing,However,formally-based curriculums have begun to weave carbon-neutral design tools into their pedagogy.This research paper critically compares how these new criteria for digital 3-D-building information modeling(BIM),and“Integrated Project Delivery”are mandating a better integration of collaborative carbon-neutral designs into the curriculum and practice of the profession.The majority of those in architectural academia have been using generative computation primarily for pure,aesthetic form-finding,without applying zero-carbon-energy-driven global performance metrics and CO_(2)e reduction strategies to reiterate derived carbon-neutral designs.The advantage of 3-D-parametric design is that it links variables,dimensions,and materials to geometry in a way that when an input or simulation value changes,the 3-D/4-D model automatically updates all life-cycle scenarios and components simultaneously.