Search Results (1,529)

This paper proposes a replicable, city-oriented workflow to support the preliminary screening of photovoltaic (PV) opportunities in Bogotá, Colombia, by integrating (i) georeferenced spatial inventories (roofs/land), (ii) solar-resource modeling based on local meteorological stations and radiation models, and (iii) an optional 3D module (LiDAR/DSM) to refine shading and orientation losses when higher-resolution data are available. Rather than claiming a complete citywide quantification from exhaustive building-level inputs, the workflow is demonstrated through two institutional case studies (public schools) selected to represent contrasting urban morphologies. The results show how the approach consistently transforms spatial constraints and solar estimates into comparable technical and economic indicators for decision-making at the site level. Finally, a practical scale-up pathway is described to extend the same logic from pilots to citywide portfolios through batch processing of urban footprints and the progressive enrichment of inputs—from 2D GIS screening to targeted 3D refinement—while preserving transparency and traceability of assumptions. For the two case study sites, the workflow yielded preliminary PV capacities of 72.6 and 95.0 kWp, with year-1 generation of 90.2 and 115.0 MWh, respectively. The IRR values achieved were between 18.9 and 19.5%, the simple payback period was approximately five years, and the LCOE was between 0.051 and 0.053 USD/kWh. It should be noted that the generation was reported as a central estimate with ±25% tolerance to reflect interannual solar resource variability. Full article

To address global carbon reduction demands, oxy-fuel combustion in circulating fluidized beds (oxy-CFB) has emerged as a highly promising carbon capture technology, offering extensive fuel flexibility and facilitating bioenergy with carbon capture and storage (BECCS). However, its commercialization is hindered by significant energy penalties and complex scale-up challenges. This review comprehensively analyzes the fundamental multiphase mechanisms, heat transfer behaviors, and multi-pollutant emission characteristics of oxy-CFB systems, drawing upon multiscale modeling advancements and operational data from pilot to 30 MW_th industrial demonstrations. Replacing air with an O₂/CO₂/H₂O mixture fundamentally alters gas–solid hydrodynamics and char conversion pathways, necessitating active fluidization state re-specification. Despite shifting optimal desulfurization temperatures and introducing recarbonation risks, the technology demonstrates inherent advantages in synergistic pollutant control, including the complete elimination of thermal NO_x. While atmospheric oxy-CFB is technically viable, transitioning to pressurized operation is critical to minimizing system efficiency penalties. Furthermore, integrating oxygen carrier-aided combustion (OCAC) and developing advanced predictive control strategies are essential to managing multi-module thermal inertia and enabling rapid dynamic responsiveness for modern power grids. Full article

Hydrogen-mediated microbial electrosynthesis (MES) of chemicals from CO₂ relies on effective gas–liquid transfer at the cathode interface, yet the extent to which cathode surface area regulates acetate productivity remains insufficiently quantified. In this study, three identical MES reactors equipped with stainless-steel cathodes of different geometric areas (8 × 1, 8 × 4, and 8 × 16 cm²) were operated at a constant electric current of 0.3 A. The largest cathode significantly accelerated hydrogen mass transfer (k_La = 0.592 h⁻¹), reaching dissolution equilibrium within 3 min, which was nearly twice as fast as the smallest electrode. Upon inoculation with enriched acetate-producing microbial consortia, the 8 × 16 cm²_cathode reactor fed with CO₂ achieved the highest steady-state acetate concentration of 32 g·L⁻¹ produced at a rate of 2.12 g·L⁻¹·d⁻¹, with 94% hydrogen utilization, and 59% coulombic efficiency. In contrast, smaller electrodes exhibited rapid bubble detachment and reduced residence time, thereby limiting microbial gas uptake, and resulting in low acetate productivity. These findings demonstrate that cathode surface area is a key engineering lever controlling both hydrogen availability and electron recovery efficiency in H₂-driven MES. The results provide practical guidance for electrode design and scale-up of CO₂-to-acetate bioconversion via the MES process. Full article

Among the most structurally diverse biomacromolecules, polysaccharides have attracted increased attention as nanocarriers for precision medicine due to their inherent biocompatibility and versatility in functionalization. Molecular features, such as monomer composition, glycosidic linkages, charge density, and chemical modification, essentially determine the nanoscale assembly process of these biopolymers, as well as their biological compatibility. This review highlights the role of these properties in the assembly process of polysaccharide-based nanocarriers leading to a variety of self-assembled nanostructures, such as polyelectrolyte complexes, protein–polysaccharide complexes, amphiphilic micelles, vesicles, hybrid systems, and nanogels, which are extensively discussed throughout the review. This review also focuses on the structure–property–function relationships of nanocarriers as applied to the rapidly developing area of precision medicine, emphasizing the problems of sustainability and reproducibility. By combining the principles of molecular engineering, supramolecular assembly, and measurable properties, this work aims to present a unified view of the molecular engineering of polysaccharide-based nanocarriers for enhanced translation potential, as well as to outline a coherent framework for the rational development of next-generation polysaccharide-based nanocarriers with improved clinical relevance. Full article

This study explores the potential of using paper pulp mill sludge (PPMS) as an economical substrate for producing high-value protease enzymes with an indigenous bacterial strain, Bacillus tropicus P4. Isolated directly from PPMS, B. tropicus P4 showed high protease-producing ability, approximately 134 U/mL after 48 h—more than three times the yield of the benchmark strain (B. megaterium). Among various additives tested to boost enzyme production, Tween 80 emerged as the most effective, increasing enzyme activity by more than threefold compared to the control. Scale-up experiments in bioreactors of 5 L and 150 L confirmed that B. tropicus P4 maintains high protease yields under typical cultivation conditions with minimal modifications, specifically the addition of Tween 80 (1%) and increased total solids concentration (25 g/L). In the 5 L bioreactor, enzyme production peaked at approximately 755 U/mL within 24 h, while the 150 L bioreactor consistently achieved high enzyme activity (~848 U/mL). These results support the feasibility of a simple and scalable approach for converting industrial sludge into high-value protease enzymes, contributing to resource recovery and circular bioeconomy strategies. Full article

Qualification is the evidence-based process through which confidence is established that a component will perform its intended function, in its intended environment, for its intended lifetime, with the required reliability. It is an owner-led activity that defines the type, quantity and quality of data required for codification and for the industrial deployment of components and their structural materials. This paper presents a structured qualification framework and applies it to a fusion machine breeder blanket structure as a representative component. It demonstrates that qualification, rather than material properties alone, dictates the use of fusion structural materials and the deployment of such materials under ASME BPV and AFCEN RCC codes. Current limitations in addressing irradiation synergy, liquid metal corrosion, and joint integrity expose gaps that these codes cannot yet prescribe. Two contrasting structural blanket material case studies: metallic-based ferritic-martensitic steel Eurofer97 and non-metallic-based silicon carbide fibre-reinforced composites (SiC_f/SiC) are used to illustrate the differing evidence requirements for each system type. Industrial scale-up considerations, including alloy specifications, manufacturing readiness, inspection reliability, and supply-chain maturity, are evaluated alongside the need for internationally harmonised datasets and design methodologies. Fusion programmes can use a phased qualification strategy in which early, time-limited operation under controlled conditions builds the evidence needed for codification and scale-up, with the required pre-operation qualification level depending on risk, component criticality and failure consequences, and with the pace of qualification ultimately setting how quickly industry can supply components for commercial fusion. Codification remains essential for commercial deployment because construction codes express codified material behaviour through allowable stresses and permitted fabrication routes, enabling designers to use advanced materials without disclosing proprietary data. In jurisdictions where ASME BPV compliance is mandatory, codification determines whether a material may enter pressure boundary service and must therefore form part of the fusion machine owner’s long-term strategy for deployment. Full article

Silicon carbide (SiC) and SiC fiber-reinforced SiC matrix composites (SiC/SiC) are receiving renewed attention for use in next-generation fusion reactors due to their ability to withstand extreme conditions, including high temperatures, neutron irradiation, and plasma interactions. General Atomics Electromagnetic Systems (GA-EMS) has demonstrated significant progress in scaling up the fabrication of SiC/SiC, achieving high mechanical uniformity and meeting dimensional requirements in components up to 12 feet in length. Key developments are discussed including scale-up of the chemical vapor infiltration (CVI) process from lab-scale to full sized parts, high-dose (100 dpa) irradiation testing, nuclear-grade ceramic joining technologies, and production-focused quality control with the collective aim to establish SiC/SiC as a reliable solution for structural and functional components in fusion systems. Beyond manufacturing, the paper addresses supply chain barriers, particularly the limited availability and high cost of nuclear-grade SiC fiber. GA-EMS is developing a novel SiC fiber production method based on a thermochemical cure step that is anticipated to reduce costs compared to traditional approaches. Additionally, advancements in engineered SiC materials, such as SiC foams and tungsten-graded SiC composites, are discussed as promising solutions for specific fusion reactor components. Full article

The Cinnamomum camphora seed kernel (CCSK) shows great promise as a natural source of bioactive alkaloids. However, there is little data about recovering alkaloids from CCSK by-products after oil extraction using an aqueous method. This study aimed to establish an efficient technology for enriching CCSK alkaloids (including magnoflorine, lindoldhamine and N,N-methyldomesticinium) using macroporous resin technology. The results showed that XR918C resin was the most suitable adsorbent due to its high adsorption/desorption capacity for CCSK alkaloids. The adsorption process was best described by Langmuir isotherm models and pseudo-second-order kinetics; it was spontaneous and physical in nature. The optimum procedure for CCSK alkaloids enrichment using XR918C resin was as follows: for adsorption, the injection flow rate and sample volume were 2.0 BV/h and 7.0 BV, respectively; for desorption, the eluent type, elution flow rate and volume were 80% ethanol, 2.0 BV/h and 6.0 BV, respectively. Furthermore, the scale-up of the CCSK alkaloid enrichment process was performed under optimal conditions. Following the 10-fold scale-up enrichment, the content of CCSK alkaloids was raised 4.41-fold, with a recovery rate of 89.19 ± 0.01%. After nine regeneration cycles, the efficiency of the XR918C resin remained stable, indicating its good reusability. In addition, CCSK alkaloids exhibited strong in vitro antioxidant activity. This study provides a useful reference for the industrial-scale enrichment of CCSK alkaloids. Full article

Polyethylene terephthalate (PET) plays a pivotal role in the chemical fiber industry, constituting over 50% of fiber consumption. However, the reduction of the recycled fiber-derived viscosity of the PET significantly impacts its spinning performance and restricts its closed-loop recycling to high-value regenerated fibers. To address these limitations, this study explored the viscosity improvement of black and white waste fiber-derived polyester particles through a two-step process involving micro-glycolysis and self-polycondensation. Initially, a continuous micro-glycolysis of fiber-derived PET was carried out in a twin-screw extruder with ethylene glycol (EG), which effectively cleaves the ester bonds in the PET chains, generating oligomers with reactive hydroxyl end groups. Subsequently, these oligomers were repolymerized without purification, and a higher molecular weight regenerated PET with enhanced intrinsic viscosity was obtained with antimony ethylene glycolate (Sb-EG) as a catalyst. The results revealed that the intrinsic viscosity decreased exponentially with increasing EG dosage during glycolysis, reaching approximately 50% of the initial value at 0.2–2 phr EG dosages. Optimal viscosity enhancement was achieved at a polycondensation time of 1–3 h, resulting in improved thermal stability and reduced crystallization temperatures. Importantly, regenerated PET samples with EG dosages of ≤2 phr demonstrated intrinsic viscosities of about 0.70 dL/g, meeting the standard for spin-grade polyester fiber, which is used to produce regenerated polyester fibers. This recycling process is low cost, environmentally friendly, and easy to scale-up, contributing significantly to the development of industrial recycling of waste polyester fabrics. Full article

The Democratic Republic of the Congo faces a high tuberculosis (TB) burden. In 2022, 61% of an estimated 402,000 TB cases were reported (World Health Organization Global tuberculosis report). To enhance case detection, the national TB program (NTP) introduced a program quality and efficiency approach (PQE), integrating systematic TB screening into outpatient departments (OPDs). Observational data of the PQE on the TB care cascade (from screening to treatment) across 70 sites in Kinshasa that initiated PQE during the first quarter of 2023 are presented. Data were collected monthly and validated during supervision visits, and disaggregated by sex, healthcare facility type (public, private, or faith-based), facility level (primary or secondary), and OPD within each facility. In 2024, 639,464 individuals were consulted in various OPDs in the participating facilities, 57% of which were female. The median number needed to screen (NNS) was 22.1, with an interquartile range of [9.5–104.3]. There was a significantly lower NNS observed in general practice and human immunodeficiency virus departments. Throughout the TB care cascade, women were less likely than men to be screened, tested, or treated. These findings, to be interpreted within the context of Kinshasa pilot facilities, provide insights to the NTP for developing PQE implementation research aimed at understanding the reasons for these discrepancies and informing NTP scale-up at the national level. Full article

The water–energy–carbon (WEC) nexus provides a systems framework for minimizing trade-offs among water security, energy reliability, and carbon mitigation. Within this framework, waste-derived biochar catalysts offer a circular pathway that simultaneously valorizes residues, reduces process energy demand, and supports carbon management through stable carbon storage and catalytic co-benefits. This review consolidates recent advances in biochar-based catalysts engineered from agricultural, industrial, municipal, and sludge-derived wastes, highlighting how feedstock selection and thermochemical processing, namely pyrolysis, hydrothermal carbonization (HTC), and torrefaction, as well as activation and post-modification (heteroatom doping and metal/metal-oxide incorporation) govern structure–property–performance relationships. The synthesized catalysts have been widely applied in water and wastewater treatment, including adsorption–advanced oxidation process (AOP) hybrids, Fenton-like systems, peroxydisulfate/persulfate (PS) and peroxymonosulfate (PMS) activation, photocatalysis, and the removal of emerging contaminants. They have also demonstrated strong potential in energy conversion processes such as the hydrogen evolution reaction (HER), oxygen reduction and evolution reactions (ORR/OER), biomass reforming, and carbon dioxide (CO₂) conversion. In addition, these materials contribute to carbon management through sequestration pathways, avoided emissions, and life cycle assessment (LCA)-based sustainability evaluations. Finally, we propose a WEC-aligned design roadmap integrating techno-economic analysis (TEA), LCA, and scale-up considerations to guide next-generation biochar catalysts toward robust performance in real matrices and deployment-ready systems. Full article

The increasing interest in valorizing agricultural by-products has positioned grape pomace as a rich source of bioactive compounds. This study developed an effect-directed extraction (EDE) approach guided by bioactivity quantification on thin layer chromatography (TLC). Twelve grape pomaces were screened based on antioxidant and tyrosinase inhibitory properties. Using hydroalcoholic solvent (ethanol:water, 1:1), the two most promising sources (Malbec from San Rafael) were subjected to response surface methodology (RSM) to optimize extraction of anti-browning and antioxidant compounds visualized as TLC spots. Temperature and time were optimized (76 °C, 45 min), and samples were analyzed using TLC coupled with DPPH and laccase inhibition bioautography. Antioxidant compounds showed retention factor values on TLC plates of 0.37 and 0.75 (DPPH/ABTS-active), while laccase inhibition occurred at Rf 0.35, coinciding with the primary tyrosinase inhibition zone. However, subsequent bioassay-guided HPLC fractionation and HRMS/MS analysis revealed that tyrosinase and laccase inhibitions are mediated by distinct compounds within this bioactive zone, highlighting a synergistic multi-target effect in the optimized extract that is retained throughout the process. The primary tyrosinase inhibitor at Rf ~0.35 was tentatively elucidated as an acylated anthocyanin, consistent with malvidin-3-O-(p-coumaroyl)glucoside. Optimized extracts were evaluated on Pink Lady apple slices at different timepoints. The browning index was reduced by 25% versus the control at 15 h, confirmed by significantly lower ΔE values (p < 0.05). The process requires only food-grade solvents and conventional equipment, facilitating scale-up for grape pomace generated worldwide. Validating the EDE strategy, this TLC-guided approach successfully tracked and preserved the primary anti-tyrosinase activity from the crude waste matrix down to the tentatively identified molecule, contributing to circular economy objectives in the wine industry. Full article

Gadolinium nanoparticles (GdNPs) have gained increasing attention as multifunctional metal-based nanoplatforms that extend far beyond their traditional use as magnetic resonance imaging (MRI) contrast agents. Their specific magnetic properties, tunable physicochemical features, and tunable biocompatibilities with biocompatible coatings give them great potential as drug delivery and theranostic applications. They offer greater stability, lower systemic toxicity, and more surface modification options compared to molecular gadolinium chelates. The functionalized GdNPs not only show excellent properties as drug carriers for their specific indications but also serve as agents in various imaging modalities with superior therapeutic efficacy by means of radio sensitization and magnetically assisted delivery. Note too that GdNP-based formulations have demonstrated synergistic activity when administered with chemotherapeutic agents such as doxorubicin. GdNPs have demonstrated promising preclinical outcomes, and their clinical translation remains restricted due to a number of scale-up constraints, long-term safety challenges, pharmacokinetics, and regulatory problems. This review provides information on the use of GdNPs, their key physicochemical and magnetic properties, ligand engineering for targeted delivery, and biological mechanisms of their theranostic performance. Full article

The electrochemical conversion of CO₂ into value-added aromatic carboxylic acids represents an emerging route for carbon utilization. This work investigates the regioselective electrochemical synthesis of ortho- and para-hydroxybenzoic acids (o-HBA and p-HBA) from CO₂ using a stirred batch cell, supported by a phenomenological Aspen Plus (version 12) model to assess process-level behavior. Experiments conducted at −1.2 V vs. Ag/AgCl, 3 atm CO₂, and 50 °C achieved yields of 58.4 ± 2.1% for o-HBA and 40.2 ± 1.6% for p-HBA, with a combined selectivity of 64.8%. Faradaic efficiencies were 76.2% (o-HBA) and 66.8% (p-HBA). A complete carbon balance, including dissolved inorganic carbon species, was established, demonstrating a single-pass CO₂ conversion of 42.6% and an overall conversion of 74.8% when the recycle loop was considered. Aspen Plus simulations based on ELECNRTL(Electrolyte Non-Random Two-Liquid model) thermodynamics and RYield fitting reproduced qualitative trends but underpredicted yields (21% and 9% for o- and p-HBA, respectively), reflecting the limitations of non-kinetic modeling. Sensitivity analyses confirmed that both electrolysis temperature and electrolyte concentration substantially influence yields and purity. This work provides reproducible electrochemical data, process-level mass balances, and a validated phenomenological simulation framework for future scale-up studies. Full article

Heyndrickxia coagulans is widely used for industrial L-lactic acid production, but carbon catabolite repression (CCR) and its link to fermentative metabolism remain poorly understood. A ccpA deletion mutant (ΔccpA) and a complementation strain (C-ccpA) were constructed to investigated the physiological, enzymatic, and transcriptomic consequences of CcpA loss. Deletion of ccpA completely abolished glucose-mediated CCR, enabling simultaneous glucose–xylose co-utilization, and triggered a marked shift from L-lactic to mixed-acid fermentation, with an 82.5% reduction in lactate titer accompanied by 24.1-fold and 51.6-fold increases in acetate and formate, respectively. Enzyme activity assays showed that L-lactate dehydrogenase activity was reduced by half, whereas acetate kinase activity increased nearly six-fold. Transcriptomic analysis revealed downregulation of ldhL and upregulation of pflB and ackA. Scale-up fermentation in a 5 L bioreactor confirmed that the wild type directed 90.2% of carbon flux to lactate (yield, 0.95 g/g glucose), compared with only 24.5% in the mutant. All phenotypes were fully restored upon complementation. These results demonstrate that CcpA is as an indispensable dual regulator of both CCR and L-lactic fermentation, providing a foundation for rational metabolic engineering of H. coagulans. Full article