Preferred Configuration Research Articles

A Case Study on Integrating an Eco-Design Tool into the Construction Decision-Making Process

To enhance the sustainability of construction and meet the sector’s environmental agenda, it is essential to comprehensively scrutinize the environmental, social, and economic impacts of construction projects from the project’s design stage. Such assessment is of utmost importance to minimize the impacts of both new construction and rehabilitation projects and is particularly critical during the selection of building materials and construction solutions. This work reports improvements in functionality and user-friendliness of an eco-design tool (UAveiroGreenBuilding) targeting the construction/rehabilitation sector and previously developed within our research group. The optimized version of the eco-design tool underwent validation through the assessment of competitive window frame materials (e.g., wood, PVC, and aluminum) for potential implementation in a rehabilitation project. Windows with PVC frames were identified as the preferred window configuration due to their superior environmental performance and favorable economic profile. Additionally, a digital communication interface was developed to connect the eco-design tool with building information modeling (BIM) projects, achieved through a routine integrated using a Dynamo application. Such successful integration not only streamlined and expedited the data transfer process by obviating the need for manual input but it also enabled the storage of environmental data throughout the life cycle of the project using a simple and reliable data storage protocol.

Computational insights into graphene-based materials for arsenic removal from wastewater: a hybrid quantum mechanical study

The discharge of industrial wastewater, particularly from chemical and mining industries, poses significant threats to the environment, public health, and safety due to high concentrations of pollutants leading to serious illnesses and the loss of aquatic life. It is therefore essential and urgent to devise measures for mitigating these threats. To advance the understanding of graphene membranes for Arsenic (As) removal from wastewater, this research investigates As adsorption and its relative selectivity on graphene-based materials using computational approaches. Our study employed hybrid quantum mechanical calculations for energy and geometry optimization to explore As adsorption on pristine graphene membrane surfaces in vacuum and aqueous environments. We assessed the effect of different adsorption sites on the surface which includes the top (T), bridge (B), and hollow (H) sites across the edge (E) and center (C) regions of the absorbent surface, to identify the optimal site/mode of adsorption. Our results demonstrate that the edge sites are the most effective for adsorption, exhibiting strong adsorption energies in both vacuum (− 1.98 eV) and aqueous environments (− 1.97 eV). These values are significantly higher than the adsorption energies for water on the surface, which range from − 0.25 to − 0.26 eV. Geometrical analyses confirmed the bridge edge sites as the most preferred adsorption configuration. Our findings not only advance upon existing computational approaches for designing efficient adsorbents but also provide deeper insights into the adsorption mechanisms on graphene-based materials. Unlike previous studies, which focused primarily on experimental or theoretical aspects in isolation, this work integrates computational and theoretical approaches to optimize adsorption processes at the molecular level. By investigating membrane properties for As removal, this research offers a novel pathway for developing advanced adsorbents, addressing critical challenges in environmental remediation with greater precision and efficiency.Graphical

Comparison of uranium complexes with methyl-glutarimidedioxime vs. glutarimidedioxime: A methyl change generates different consequences in thermodynamic equilibria and coordination modes

Nuclear power serves as an important source of alternative energy. However, land uranium resources are limited. In contrast, seawater contains an estimated total of 4.5 billion metric tons of uranium, which is more than a thousand times as much as that found in terrestrial ores. Therefore, developing techniques for uranium extraction from seawater is attracting research attention. Amidoxime-functionalized polymer fibers are the most widely utilized sorbents for this purpose. On the surface of amidoxime-based sorbents, cyclic glutarimidedioxime (H2A) is the preferred configuration for sequestration of uranium from seawater. Methyl-glutarimidedioxime (H2Q) forms if a methyl group attaches to the piperidine ring of H2A. The binding strength of uranyl complexes with H2Q and the enthalpy of complexation were investigated via potentiometry and microcalorimetry, respectively. The coordination mode was further revealed by single-crystal X-ray diffraction. It was expected that H2A and H2Q should be identical in terms of coordination as tridentate ligands. However, our investigation revealed that a methyl group attached to the piperidine ring not only altered the chelating mode but also lowered the binding strength of oxime groups. These findings show that developing a mechanism for optimizing molecules that would be formed on fiber surfaces remains challenging, even a methyl structural change would result in major consequences.

MOF-on-MOF Growth: Inducing Naturally Nonpreferred MOFs and Atypical MOF Growth.

ConspectusOverflowing metal-organic frameworks (MOFs) have been synthesized from a wide range of metal and organic components for specific purposes and intellectual curiosity. Each MOF has unique chemical and structural characteristics directed by the incorporated components, metal ions (or clusters), organic linkers, and their intrinsic coordination interactions. These incorporated components and structural characteristics are two pivotal factors influencing MOFs' fundamental properties and subsequent applications. Therefore, selecting the appropriate metal and organic components, considering their innate chemical and structural properties, is crucial to endow the final MOFs with the desired properties. Ultimately, producing MOFs with a desired structure using ideal components is the best approach to achieving the best MOFs tailored for specific purposes with desired properties. However, achieving MOFs with the intended structure from chosen components remains underdeveloped. In many cases, the resulting MOF structure is governed by the thermodynamically and/or kinetically preferred configuration (refers to a naturally preferred structure) of the chosen components and given reaction conditions. Additionally, producing hybrid MOFs with complex components, structures, and morphologies presents a great opportunity to obtain special MOFs with advanced properties and functions. In this Account, we outline our group's efforts over the past few years to develop naturally nonpreferred MOFs through the induced MOF-on-MOF growth process and atypical hybrid MOFs via nonstandard MOF-on-MOF growth. First, we highlight the prime strategy for producing naturally nonpreferred MOFs based on template-induced MOF-on-MOF growth. In this section, we discuss the two basic growth behaviors, isotropic and anisotropic growth of naturally nonpreferred MOFs, determined by the degree of matching between the cell lattices of the two MOFs. Second, we introduce the MOF farming concept for the productive cultivation and effective harvesting of naturally nonpreferred MOFs made by MOF-on-MOF growth. Here we discuss the importance of selecting the ideal MOF template for productive growth and developing an efficient method for harvesting cultivated MOFs. Next, we describe atypical anisotropic MOF-on-MOF growths between two MOFs with mismatched cell lattices. In this section, we introduce tip-to-middle MOF-on-MOF growth involving self-structural adjustment of the secondary MOF, logical inference of unidentified MOF structures based on MOF-on-MOF growth behavior and morphological features, and MOF-on-MOF growth accompanied by etching and transformation of the template. Finally, we discuss the perspectives and challenges of MOF-on-MOF growth and the synthesis of naturally nonpreferred MOFs. We hope that this Account offers valuable insights into the rational design and development of MOFs with desired structural and compositional characteristics, leading to the creation of ideal MOFs.

Establishing a Robust Nonlinear Targeted Switch for C1 Electroproduction in Atomic Alloy Cox/Pd Bimetallenes

Establishing a targeted switch for CO2 conversion under electric drive is essential for achieving carbon‐balance by enabling selective chemicals. However, engineering the topological assembly of active sites to precisely regulate the competing pathways for various intermediates has been plagued by unclear structure‐function relationships. To tailor the CO/formate pathways, herein we established a robust nonlinear targeted switch with tunable active Cox sites integrated into Pd metallene, which involves Co1/Pd single‐atom alloy (favoring CO) and Co2/Pd diatomic alloy (favoring formate). Transitioning from Co1/Pd to Co2/Pd atomic alloy bimetallenes resulted in a nonlinear, high‐contrast flip in selectivity, surpassing 94% for CO and formate productions in both H‐cell and flow cell. Furthermore, the superior selectivity and current efficiency for CO (> 80 %) and formate (> 88%) were consistently maintained at ‐150 mA cm‐2 over continuous 200 h. Theoretical simulations and in‐situ spectroscopy analyses unveiled that appropriate adjacent metal site combinations (Pd‐Pd, Pd‐Co and Co‐Co) lead to tunable dz2 band center and a nonlinear shift in preferred adsorption configurations of intermediates, dictating the C1 pathways. Our finding reveals a desired switch in C1 selectivity and robust stability within Cox/Pd system, providing a new perspective for fine‐tuning energy conversion processes through specific topological assembly.

Establishing a Robust Nonlinear Targeted Switch for C1 Electroproduction in Atomic Alloy Cox/Pd Bimetallenes.

Establishing a targeted switch for CO2 conversion under electric drive is essential for achieving carbon-balance by enabling selective chemicals. However, engineering the topological assembly of active sites to precisely regulate the competing pathways for various intermediates has been plagued by unclear structure-function relationships. To tailor the CO/formate pathways, herein we established a robust nonlinear targeted switch with tunable active Cox sites integrated into Pd metallene, which involves Co1/Pd single-atom alloy (favoring CO) and Co2/Pd diatomic alloy (favoring formate). Transitioning from Co1/Pd to Co2/Pd atomic alloy bimetallenes resulted in a nonlinear, high-contrast flip in selectivity, surpassing 94 % for CO and formate productions in both H-cell and flow cell. Furthermore, the superior selectivity and current efficiency for CO (>80 %) and formate (>88 %) were consistently maintained at -150 mA cm-2 over continuous 200 h. Theoretical simulations and in situ spectroscopy analyses unveiled that appropriate adjacent metal site combinations (Pd-Pd, Pd-Co and Co-Co) lead to tunable dz 2 band center and a nonlinear shift in preferred adsorption configurations of intermediates, dictating the C1 pathways. Our finding reveals a desired switch in C1 selectivity and robust stability within Cox/Pd system, providing a new perspective for fine-tuning energy conversion processes through specific topological assembly.

Offshore Market Design in Integrated Energy systems: A Case Study on the North Sea Region towards 2050

Offshore grids, with multiple interacting transmission and generation units connecting to the shores of several countries, are expected to have an important role in the cost-effective energy transition. Such massive new infrastructure expanding into a new physical space will require new offshore energy market designs. Decisions on these designs today will influence the overall value potential of offshore grids in the future. This paper investigates different possible market configurations and their impacts on operational costs and required congestion management, as well as prices and emissions. We use advanced integrated energy system optimisation, applied to a study case on the North Sea region towards 2050. Our analysis confirms the well-known concept of nodal pricing as the most preferable market configuration. Nodal pricing minimises costs (0.2–1.6 b€/year lower) and CO2 emissions (0.6–5.6 Mton/year lower) with respect to alternative market designs investigated. The performance of the different market designs is highly influenced by the overall architecture of the offshore grid, and the rest of the energy system. E.g., flexibility options help reducing the spread between the designs. But the results are robust: nodal pricing in offshore grids emerges as the preferable market configuration for a cost-effective energy transition to carbon neutrality.

Exploring Electrolyte Adsorption on the Different Types of Layered Cathode Surfaces in Lithium-Ion Batteries via a Universal Neural Network Potential Method.

LiNi x Mn y Co z O2 (NCM) is a promising cathode material for lithium-ion batteries. Their long-term stability and impedance growth as cycles are strongly influenced by the properties of the cathode electrolyte interface (CEI), formed by the reaction between the electrolyte and electrode surface. Understanding of these interactions at the atomic level of the NCM electrode surface and electrolyte will provide a new strategic approach for the design of a highly functional CEI layer. In this study, we explored the influence of Ni content in transition metal layers on surface energies under different synthetic conditions and terminations using a density functional theory (DFT) validated universal neural network potential (UNNP) method. Furthermore, we investigated the adsorption of ethylene carbonate (EC) and dimethyl carbonate (DMC) on the most favorable NCM surfaces. EC and DMC displayed similar adsorption energy trends; however, differences were observed in the preferred configurations, which can affect the formation of the CEI.

A DFT Computational Study of Type-I Clathrates A8Sn46-x (A = Cs or NH4, x = 0 or 2).

Semiconducting clathrates have attracted considerable interest in the field of thermoelectric materials. We report here a computational study on the crystal structure, the enthalpy of formation, and the physical properties of the following type-I clathrates: (a) experimentally studied Cs8Sn44 and hypothetical Cs8Sn46 and (b) hypothetical (NH4)8Sn46-x (x = 0 or 2). The ab initio VASP calculations for the nominal stoichiometries include the geometry optimization of the initial structural models, enthalpies of formation, and the electronic and phonon density of states. Comparison of the chemical bonding of the structural models is performed via the electron localization function. The results show that the presence and distribution of defects in the Sn framework for both Cs8Sn46-x and (NH4)8Sn46-x systems significantly alters the formation energy and its electrical properties, ranging from metallic to semiconducting behavior. In particular, one defect per six-membered Sn ring in a 3D spiro-network is the thermodynamically preferred configuration that results in the Cs8Sn44 and (NH4)8Sn44 stoichiometries with narrow-band gap semiconducting behavior. Moreover, the rotation of the ammonium cation in the polyhedral cavities is an interesting feature that may promote the use of ammonium or other small molecular cations as guests in clathrates for thermoelectric applications; this is due to the decrease in the lattice thermal conductivity.

Circle packing on spherical caps

We have studied the packing of congruent disks on a spherical cap, for caps of different size and number of disks, N. This problem has been considered before only in the limit cases of circle packing inside a circle and on a sphere (Tammes problem), whereas all intermediate cases are unexplored. Finding the preferred packing configurations for a domain with both curvature and border could be useful in the description of physical and biological systems (for example, colloidal suspensions or the compound eye of an insect), with potential applications in engineering and architecture (e.g., geodesic domes). We have carried out an extensive search for the densest packing configurations of congruent disks on spherical caps of selected angular widths (θmax=π/6, π/4, π/2, 3π/4, and 5π/6) and for several values of N. The numerical results obtained in the present work have been used to establish (at least qualitatively) some general features for these configurations, in particular the behavior of the packing fraction as function of the number of disks and of the angular width of the cap, or the nature of the topological defects in these configurations (it was found that as the curvature increases, the overall topological charge on the border tends to become more negative). Finally, we have studied the packing configurations for N=19, 37, 61, and 91 (hexagonal numbers) for caps ranging from the flat disk to the whole sphere, to observe the evolution (and eventual disappearance) of the curved hexagonal packing configurations while increasing the curvature.

Evaluation of Modeled Diurnal Warming Estimates for Application to Producing Sea Surface Temperature Analyses

AbstractAccurate knowledge of the amount of diurnal warming present in sea surface temperature (SST) observations at different times and effective depths is important for multiple applications including the production of blended SST analyses. This work explores the ability of a modified Kantha‐Clayson‐type one‐dimensional mixed layer ocean model with wave effects to accurately simulate the observed diurnal warming amplitude over a global grid when forced with coarse resolution numerical weather prediction (NWP) outputs. The sensitivity of the modeled diurnal amplitudes to multiple adjustable parameters and model configurations is evaluated to determine whether a preferred configuration can be identified that yields reliable predictions. The accuracy of the predictions is determined through comparison against estimates from operational SST retrievals from geostationary satellites. The results show that a single configuration can yield predictions that reproduce the observed range of diurnal warming amplitudes across a range of seasons and locations and an accurate occurrence frequency of the largest amplitude events. Simulated amplitudes fall along the one‐to‐one line with observations but with significant scatter due to factors including positioning of the NWP fluxes. The identified configuration is also shown to favorably reproduce diurnal warming observations from multiple research cruises. Overall uncertainty of the simulated diurnal warming amplitude across the different tests ranges between 0.4 K for all observations to ∼1 K for the largest warming events. While the focus is not on model comparisons, the results show improved performance relative to other models. Use of the model appears warranted but the associated uncertainty must be considered.

Erosive wear and particle attrition in multi-stage solar particle receivers and screw conveyors: A CFD-DEM approach with machine learning and artificial neural networks

A coupled finite volume and discrete element method (CFD-DEM) numerical model is developed to unravel the fundamental mechanisms of granular transport, surface erosive wear and particle attrition in multistage solar particle receivers (MSPR) and screw conveyors (SC). Additionally, various regression-based supervised machine learning (ML) and artificial neural networks (ANN) are trained and optimized with the goal of quickly quantifying erosion and attrition thereby overcoming (a) the inherent challenges of high computational expense of CFD-DEM simulations and (b) exorbitant time required to post-process and extract DEM results. This study is the first of its kind to harness a synergistic numerical framework (CFD-DEM, ML, ANN) to unravel the fundamental mechanisms of erosion and attrition in MSPRs, non-vibrationally induced SCs, and vibrationally-induced SCs. It is found that the packing distribution, particle curtain width, and severity of particle scattering in a MSPR exhibits a subtle variation with particle diameter. In the context of SCs, the magnitudes of erosion and attrition are contingent on the particle diameter and flow operating conditions such as screw blade velocity, vibrational frequency and vibrational amplitude. Interestingly, a vibrationally-induced SC (VI-SC) exhibits superior performance in terms of low erosion and attrition unlike non-vibrationally induced SC (NVI-SC). It is found that MSPRs with 750–1000 µm particles and SCs with 750–1000 µm coupled with vibrational frequencies and vibrational amplitudes of 5 Hz and 0.007 m, respectively, are the preferred configurations due to minimum particle scattering, low erosive wear and low particle attrition. The trained and optimized ML models such as XGBoost, CatBoost, and Multilayer Perceptron (MLP) exhibit superior performance in predicting erosive wear and particle attrition on unseen DEM data, whereas the Multiple Linear Regression (MLR) and Gaussian Process Regression (GPR) ML exhibit poor performance prediction. For the first time, new information on fundamental granular flow dynamics, erosive wear and particle attrition in MSPRs and SCs is discerned. The methodology allows scientists to quickly examine material degradation for a myriad of industrial applications such as concentrated solar thermal (CST), among others.

Developing feasible person-centred care alternatives to emergency department responses for adults with epilepsy: a discrete choice analysis mixed-methods study.

Calls have been made for paramedics to have some form of care pathway that they could use to safely divert adults with epilepsy away from emergency departments and instigate ambulatory care improvements. Different configurations are possible. To know which to prioritise for implementation/evaluation, there is a need to determine which are acceptable to service users and likely National Health Service-feasible. (1) Identify configurations being considered, (2) understand service users' views of them and current provision, (3) identify what sort of care service users want and (4) determine which configuration(s) is considered to achieve optimal balance in meeting users' preference and being National Health Service-feasible. Service providers were surveyed to address objective 1. Interviews with service users addressed objective 2. Objective 3 was addressed by completing discrete choice experiments. These determined users' care preferences for different seizure scenarios. Objective 4 was addressed by completing 'knowledge exchange' workshops. At these, stakeholders considered the findings on users' stated preferences and judged different pathway configurations against Michie's 'acceptability, practicability, effectiveness, affordability, side-effects and equity' feasibility criteria. This project took place in England. The survey recruited representatives from neurology and neuroscience centres and from urgent and emergency care providers. For the interviews, recruitment occurred via third-sector support groups. Recruitment for discrete choice experiments occurred via the North West Ambulance Service NHS Trust and public advert. Workshop participants were recruited from neurology and neuroscience centres, urgent and emergency care providers, support groups and commissioning networks. Seventy-two services completed the survey. Interviews were conducted with 25 adults with epilepsy (and 5 relatives) who had emergency service contact in the prior 12 months. Discrete choice experiments were completed by 427 adults with epilepsy (and 167 relatives) who had ambulance service contact in the prior 12 months. Workshops were completed with 27 stakeholders. The survey identified a range of pathway configurations. They differed in where they would take the patient and their potential to instigate ambulatory care improvements. Users had been rarely consulted in designing them. The discrete choice experiments found that users want a configuration of care markedly different to that offered. Across the seizure scenarios, users wanted their paramedic to have access to their medical records; for an epilepsy specialist (e.g. an epilepsy nurse, neurologist) to be available to advise; for their general practitioner to receive a report; for the incident to generate an appointment with an epilepsy specialist; for the care episode to last < 6 hours; and there was a pattern of preference to avoid conveyance to emergency departments and stay where they were. Stakeholders judged this configuration to be National Health Service-feasible within 5-10 years, with some elements being immediately deployable. The discrete choice experiment sample was broadly representative, but those reporting recent contact with an epilepsy specialist were over-represented. Users state they want a configuration of care that is markedly different to current provision. The configuration they prefer was, with support and investment, judged to likely be National Health Service-feasible. The preferred configuration should now be developed and evaluated to determine its actual deliverability and efficacy. The study is registered as researchregistry4723. This award was funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme (NIHR award ref: 17/05/62) and is published in full in Health and Social Care Delivery Research; Vol. 12, No. 24. See the NIHR Funding and Awards website for further award information.

Development of Sub-County Cancer Reporting Zones in Delaware and Example Use Case for Targeted Interventions.

To describe the Delaware Cancer Registry (DCR)'s participation in the National Cancer Institute (NCI)/North American Association of Central Cancer Registries (NAACCR) Zone Design Project to create sub-county geographic areas ("zones") for use in cancer reporting and geospatial analysis. DCR and other stakeholders reviewed up to ten unique zone configurations for each of Delaware's three counties. The zone configurations were created using AZTool and were set to optimize three objectives: create zones that have a minimum and target population of 50,000; are homogenous based on the variables of percent minority, percent below poverty, and percent urban; and are as compact as possible. The DCR sent a survey to stakeholders to provide input on their preferred zone configuration for each county. Following the final selection of zones, the DCR utilized the geographies for calculating overall and late-stage breast cancer incidence statistics and created choropleth maps to visualize the rates by quintiles. The final selections resulted in a total of 15 zones for Delaware, with three in Kent County, nine in New Castle County, and three in Sussex County. The zones ranged in population size from 54,013 to 67,693 people. Zones with higher late-stage breast cancer incidence rates included those near the areas of Wilmington, Middletown, and between Milford and Georgetown. Comparing results of overall breast cancer incidence rates by zone with late-stage rates by zone, there were areas that had lower relative overall breast cancer incidence rates but were relatively higher for late-stage rates by zones or vice versa. Aggregating census tracts into zones allows for reporting reliable cancer rates at sub-county levels, which is instrumental in conveying meaningful information about regional cancer trends to stakeholders and the public. Delaware will be able to utilize zone-level cancer information to provide targeted interventions and outreach initiatives.

Dynamics of water adsorption on SAPO-34: Comparison of three adsorbent bed configurations of adsorption chillers

Intensification of the adsorption dynamics is a strategic way to make adsorption chillers and heat pumps more competitive with conventional vapour compression systems. This can be achieved by consolidating the adsorbent bed with a heat exchanger to enhance heat transfer. This work investigates the dynamics of water adsorption on a commercial adsorbent SAPO-34 for three bed configurations, namely, a reference bed consisting of a monolayer of loose beads located on an aluminium plate, and two consolidated beds – a monolayer of beads glued to the plate, and a homogeneous coating of the plate prepared with binder. The morphology and texture of the prepared beds were studied by optical and scanning electron microscope techniques as well as by low temperature nitrogen adsorption. Six binders involved, both organic (hydroxyethyl cellulose, polyvinylpyrrolidone, polyaniline) and inorganic (heat-conductive compound CPTD, bentonite clay, colloidal silica sol), produced varying effects. It was found that the most preferred configuration involves SAPO beads glued to the plate with bentonite for which the heat transfer was enhanced by a factor of 1.2–1.7 while maintaining sufficient mass transfer. The effective heat transfer coefficient was measured for the most promising binders and selected configurations, and varied between 120 and 248 W/(m2 K). The heat transfer acceleration permitted the specific cooling power (at a conversion of 0.8) to increase from 2.7 kW/kg for loose beads of 0.8–0.9 mm size to 3.5 kW/kg for the same beads bound with bentonite. Thus, gluing pre-made commercial adsorbent beads with heat-exchanger with suitable binders presents a simple and promising method to enhance the adsorption dynamics, resulting in a more compact design of adsorption chillers.

Offshore Market Design in Integrated Energy systems: A Case Study on the North Sea Region towards 2050

Offshore grids, with multiple interacting transmission and generation units connecting to the shores of several countries, are expected to have an important role in the cost-effective energy transition. Such massive new infrastructure expanding into a new physical space will require new offshore energy market designs. Decisions on these designs today will influence the overall value potential of offshore grids in the future. This paper investigates different possible market configurations and their impacts on operational costs and required congestion management, as well as prices and emissions. We use advanced integrated energy system optimisation, applied to a study case on the North Sea region towards 2050. Our analysis confirms the well-known concept of nodal pricing as the most preferable market configuration. Nodal pricing minimises costs (0.2–1.6 b€/year lower) and CO2 emissions (0.6–5.6 Mton/year lower) with respect to alternative market designs investigated. The performance of the different market designs is highly influenced by the overall architecture of the offshore grid, and the rest of the energy system. E.g., flexibility options help reducing the spread between the designs. But the results are robust: nodal pricing in offshore grids emerges as the preferable market configuration for a cost-effective energy transition to carbon neutrality.

Ab initio study of the adsorption of O, O2, H2O and H2O2 on UO2 surfaces using DFT+U and non-collinear magnetism

In order to model correctly the corrosion of spent nuclear fuel under disposal conditions, it is important to understand its behavior in the presence of oxidants. To advance in this direction, we consider the oxidation of UO2. We investigate computationally the adsorption of various species on its three most stable surfaces: (111), (110), and (100), with emphasis on incorporating a full non-collinear PBE+U approach. Various species, namely O, O2, H2O and H2O2 are considered due to their relevance for the oxidation of UO2. The dissociation energy and an estimate for the dissociation barrier for O2 were obtained, using the preferred adsorption configurations of O and O2. The adsorption configurations for H2O in our study compare well with previous studies that used collinear approximations, both in terms of relative stability of configurations and bond lengths. Differences in adsorption energies were found, which may be important for reaction kinetics. Dissociative reactions in which the water molecule splits in hydrogen and hydroxyl occur only on one of the three surfaces. The hydrogen further reacts with a surface oxygen to also form a hydroxyl group. Not surprisingly, we find that H2O2 binds more strongly to the three surfaces than water (lower formation energy), and similar to H2O adsorption, dissociative reactions may occur. The dissociated hydrogen reacts with a surface oxygen to form a hydroxyl group and the hydroperoxyl molecule binds with a surface uranium. Our study, which includes a detailed study of electron transfer, magnetic structure and the preferred adsorption configurations, gives insight into the uranium oxidation states and the influence of surface geometry on adsorption. The findings contribute to a more comprehensive understanding of the early stages of UO2 oxidation.

Synthesis of isomeric β-cycloalkoxyphosphonated hydrazones containing a dioxaphosphorinane ring: Configurational and conformational investigation and molecular docking analysis

A series of Z/E isomeric β-cycloalkoxyphosphonated hydrazones [R1R2C(CH2O)2P(=O)CH2-C{=NN(H)R5}C(H)R3R4] 3 bearing a six-membered dioxaphosphorinane ring was prepared, structurally analysed, and subjected to in silico studies to assess their Acetylcholinesterase (AChE) and Butyrylcholinesterase (BuChE) inhibition activity. Furthermore, their ADMET (Absorption, Distribution, Metabolism, Excretion, Toxicity) properties were determined. Hydrazones 3 were prepared from their corresponding allenylphosphonates [R1R2C(CH2O)2P(=O)C(H)=C=CR3R4] 2 by addition of various hydrazines NH2NHR5. Since NMR studies indicated the occurrence of several isomeric species in solution, conformational and configurational studies, based on mechanistic elucidation and energy stability using Density functional theory (DFT) calculation at the B3LYP/6-311 G++ (d,p) level of theory, were performed to determine their relative predominance. The hydrazone 1-(2-oxo-1,3,2-dioxaphosphoranyl)-3-phenylpropanone 3c was crystallographically analysed by single-crystal X-ray diffraction (SCXRD), revealing the occurrence of strong intra- and intermolecular NH···O hydrogen bonding. These secondary interactions were further examined by a Hirshfeld surface analysis. The experimental SCXRD parameters are compared with the theoretical calculated ones and the preferred configuration of product 3c was determined. Furthermore, the crystal structure of the symmetric azine 2,2′-((2E,2′E)-hydrazine-1,2-diylidenebis(3-phenylpropan-1-yl-2-ylidene))bis(5-methyl-5-propyl-1,3,2-dioxaphosphinane 2-oxide) 4, resulting from the reaction between hydrazone 3a and allene 2a, has been determined. To predict whether hydrazones 3 are appropriate as anticholinesterase agents exhibiting a potential activity for treatment of the Alzheimer disease, in silico molecular docking simulations were employed to investigate the interaction modes between hydrazones 3 and the active sites of the BuChE and AChE enzymes. Additionally, an ADMET-properties prediction was carried out for selected hydrazones to determine their pharmacokinetics and drug-likeness properties.

Floating solar power plant planning based on electricity price fluctuations in Towuti, south Sulawesi

A company located in South Sulawesi, intends to mitigate emissions from the Power Plant by constructing an environmentally friendly alternative, namely the Floating Solar Power Plant (FSPP), in Towuti. The development plan involves a feasibility analysis for each configuration of the FSPP, considering technological, economic, and environmental criteria. The selection of the preferred configuration is determined using the Analytical Hierarchy Process (AHP) method, based on input from experts. According to this method, the chosen configuration is the on-grid non-battery Floating Solar Power Plant, with a Net Present Value of Rp. 1,431,159,245,752, an Internal Rate of Return of 9.46%, a Payback Period of 8.916 years, a Profitability Ind ex of 1.299, a system efficiency of 21.56%, a carbon footprint of 35,003 kg CO2, and an emission reduction of 9,136,808,273 kg CO2. Decision analysis, involving open and abandonment scenarios based on fluctuations in industrial electricity prices, was conducted using Monte Carlo simulation, yielding a volatility value of 31.2%. The real options analysis recommends abandonment in the twentieth year, with a decision success potential of 38%, based on the results.

Molecular insight into sequence-defined polyelectrolytes for energy storage devices

Polyelectrolyte (PE) adsorption on charged surfaces is a complex phenomenon that has an array of applications ranging from healthcare to designing energy storage devices. PE adsorption on surfaces involves surface charge polarization effects which arise due to the dielectric dissimilarities between the PE and the charged surface. PEs owing to their high potential window, and leakage-resistant behavior are used as supercapacitor electrolytes. Recent experimental evidence suggests co-block polymers as potential design materials for energy storage devices (ESDs). It is imperative to mention that the structural variation of the co-block polymers under spatial confinements will have a key role in designing electrodes and electrolytes for ESDs which demands a detailed investigation. This study reveals that the spatial orientations of the charged groups have an impressive impact on the changes in PE charge density peaks, charge amplification peaks, PE adsorption, counter-ion adsorption, and differential and integral capacitance while confined by graphene electrodes. It is startling to observe that the counter-ion distribution within the electrical double layer of the positively charged surface significantly depends on the orientation of the PEs. However, with increasing solvent dielectric constant the variations in the above-mentioned properties subside due to reduced electrostatic interactions. The differential capacitance and the integral capacitance are also found to be dependent on the dielectric constants of the solvent. These findings will be immensely useful in determining the key factors needed to describe the preferred spatial configuration of a PE suitable for various ESDs and applications involving PEs in a confined system.