Structure- and Size-Dependent Properties of B_nCu₂^0/– (n = 2–14) Clusters: DFT Calculations

The structural and stability properties of two Cu atoms doped boron clusters (BnCu2 with n = 2–14) are investigated by a genetic algorithm method in combination with density functional theory (DFT) calculations. The lowest energy clusters of neutral clusters (BnCu20) adopt two-dimensional (2D) structures for n ≤ 6, 10, and 12. For anionic clusters (BnCu2–) the structural patterns are similar, however, the Cu atoms tend to pair up and form dimers instead of islands. The stability of the clusters, evaluated through the binding energy, second-order energy difference, and ionization energy, reveals that the neutral clusters B4Cu20, B6Cu20, and B8Cu20, as well as the anionic clusters B9Cu2–, B11Cu2–, and B13Cu2–, have greater chemical and thermodynamic stability than their neighbors in size. The favored structures for these clusters are found to be related with stable boron motifs which correspond to magic clusters. Moreover, the Cu2–Bn interaction of the clusters were analyzed using the Energy Decomposition Analysis (EDA) and Natural Bond Order (NBO) charges, which supported the current findings. According to the AdNDP analyses, the stability of the clusters can be understood by the presence of delocalized sigma orbitals along the boron backbone

Kinetic modelling and steady-state optimization of cooling crystallization by continuous oscillatory baffled crystallizer

To address an open issue of sufficiently describing crystallization kinetics in a continuous oscillatory baffled crystallizer (COBC), a comprehensive kinetic modelling method is proposed in this paper, along with a steady-state optimization approach (SOA) for operating the COBC. Taking into account the axial dispersion of crystal quantity (ADCQ), velocity dispersion of crystal population (VDCP), and growth rate dispersion (GRD), a non-ideal plug flow micro-distribution model (NPF-MDM) is firstly established, which could be used to predict the crystal size distribution (CSD) and mean crystal size (MCS) in each zone of COBC. The model parameters are estimated by heterogeneous tracer experiments and continuous cooling crystallization (CCC) experiments in a real COBC named DN15. Based on the established NPF-MDM, an SOA is provided for operating the COBC. The tube length distribution across different temperature zones of COBC is optimized to determine the maximum attainable region of product MCS. By introducing an objective function related to the target crystal size and the CSD width of product crystals, a sensitivity analysis (SA) is presented to identify the critical operating conditions (COCs), including the seed recipe and net flow rate. Subsequently, the SA-based SOA is carried out. A growth optimizer algorithm is offered to solve the related nonconvex optimization problems. Experiments on the CCC of L-glutamic acid (LGA) via DN15 are performed to validate the proposed modelling and SOA

Towards Autonomous Subsea Longitudinal Object Detection and Tracking Using a Multi-beam Echo-Sounder

Subsea pipelines and cables are critical assets which require regular maintenance and inspection to ensure their integrity and continual operation. The autonomous tracking of these assets requires robust and reliable methods especially in the challenging subsea environment. This paper presents a new method for the robust autonomous detection and tracking of subsea pipelines and cables using a multi-beam echo-sounder sensor, leveraging intensity and profiling returns for enhanced robustness. The proposed method involves four key steps. First, prepocessing operations are carried out to refine the raw sensor data, followed by a region of interest generation using the K-means clustering algorithm, then a validation step which filters implausable regions and finally a fitting processes for determining the target's position and parameters. The proposed method is also designed to extend the detection and tracking capabilities of the system to the 3-dimensional use case. Through real-world and simulated experiments we demonstrate the effectiveness of the method

Seismic stratigraphy of the Guinea Plateau before, during and after the opening of the Equatorial Atlantic Gateway

The Guinea Plateau contains an ∼200 Myr stratigraphic record, encompassing the mid-Cretaceous opening of the Equatorial Atlantic Gateway (EAG). Here we present new 2D seismic data to constrain the structural and stratigraphic evolution of the plateau. Seismic stratigraphic analysis reveals five megasequences of ∼25–65 Myr duration: M1, a Jurassic synrift sequence with prominent seaward-dipping reflections; M2, a late Jurassic–Early Cretaceous post-rift carbonate platform; M3, a late Early Cretaceous transform clastic-dominated sequence; M4, an Albian–Maastrichtian ocean–continent transform to post-transform sequence; and M5, a Maastrichtian–recent passive margin sequence with low sedimentation rates. These megasequences also contain prominent transgressive–regressive cycles of 5–10 Myr duration, interpreted to be the result of dynamic topography.The boundary between M3 and M4 is a major erosional unconformity documenting the final continental break-up during the opening of the EAG. Above this, a pronounced Albian to Cenomanian/Turonian marine transgression resulted in marine inundation of the plateau. Structural deformation continued into the early Cenomanian along the Guinea Marginal Ridge, a potential structural barrier that restricted marine connection across the EAG. Bulk geochemical data from the shallow Guinea Plateau indicate that enhanced carbon burial in this setting was primarily driven by the deposition of reworked, oxidized organic matter during an oceanic anoxic event, independent of gateway opening

Seamounts of Cabo Verde: A review of their ecological and economic significance, anthropogenic impacts, and conservation needs

The deep-sea areas of the Cabo Verde Archipelago remain largely unexplored, with seamounts standing out as the most prominent and abundant geomorphological features. The ecological significance of these underwater structures is well-documented in various regions of the planet, as they often serve as biodiversity hotspots, stepping stones for species connectivity and, in some cases, areas with high levels of endemism. However, the biology and ecology of the seamounts around Cabo Verde are still largely unknown. Preliminary studies of the geomorphology, oceanographic characteristics and ecology of specific features suggest that the Cabo Verde seamount network — comprising 14 known conspicuous seamounts as well as smaller elevations less than 1000 m — harbours high biological diversity. That biodiversity associated with the Cabo Verde seamounts spans a wide range of forms, from microscopic organisms to cetaceans, encompassing both pelagic and benthic communities. Commercial activities associated with seamounts, in particular fishing, are a critical aspect to consider for ecosystem management. Evaluating their current uses, future prospects, and the existing and potential threats the Cabo Verde seamounts face is essential for effective and sustainable marine spatial planning. This study reviews and synthesises the current knowledge on the Cabo Verde seamounts within its Exclusive Economic Zone (EEZ), focusing on their environmental and biological aspects, including geology, oceanography, and associated biological communities. Key topics include primary production, zooplankton communities, benthic organisms, large vertebrates such as elasmobranchs, sea turtles, seabirds, and cetaceans, as well as microbes and trophic linkages. Additionally, this review explores the socio-economic dimensions linked to seamounts, highlighting their importance to the local economy and emphasizing the need for effective marine spatial management plans. These considerations are crucial for balancing conservation efforts with sustainable use, ensuring the long-term health of these vital underwater ecosystems.</p

Kinetic modelling and steady-state optimization of cooling crystallization by continuous oscillatory baffled crystallizer

To address an open issue of sufficiently describing crystallization kinetics in a continuous oscillatory baffled crystallizer (COBC), a comprehensive kinetic modelling method is proposed in this paper, along with a steady-state optimization approach (SOA) for operating the COBC. Taking into account the axial dispersion of crystal quantity (ADCQ), velocity dispersion of crystal population (VDCP), and growth rate dispersion (GRD), a non-ideal plug flow micro-distribution model (NPF-MDM) is firstly established, which could be used to predict the crystal size distribution (CSD) and mean crystal size (MCS) in each zone of COBC. The model parameters are estimated by heterogeneous tracer experiments and continuous cooling crystallization (CCC) experiments in a real COBC named DN15. Based on the established NPF-MDM, an SOA is provided for operating the COBC. The tube length distribution across different temperature zones of COBC is optimized to determine the maximum attainable region of product MCS. By introducing an objective function related to the target crystal size and the CSD width of product crystals, a sensitivity analysis (SA) is presented to identify the critical operating conditions (COCs), including the seed recipe and net flow rate. Subsequently, the SA-based SOA is carried out. A growth optimizer algorithm is offered to solve the related nonconvex optimization problems. Experiments on the CCC of L-glutamic acid (LGA) via DN15 are performed to validate the proposed modelling and SOA

The Least Action Admissibility Principle

This paper provides a new admissibility criterion for choosing physically relevant weak solutions of the equations of Lagrangian and continuum mechanics when non-uniqueness of solutions to the initial value problem occurs. The criterion is motivated by the classical least action principle but is now applied to initial value problems which exhibit non-unique solutions. Examples are provided for Lagrangian mechanics and the Euler equations of barotropic fluid mechanics. In particular, we show that the least action admissibility principle prefers the classical two shock solution to the Riemann initial value problem to certain solutions generated by convex integration. On the other hand, Dafermos’s entropy criterion prefers convex integration solutions to the two shock solutions. Furthermore, when the pressure is given by p(ρ)=ρ2, we show that the two shock solution is always preferred whenever the convex integration solutions are defined for the same initial data

Acceleration of Digitalisation in Manufacturing SMEs Through Capability Maturity Assessment

Digitalisation enables organisations to redesign their value propositions, processes and systems. The value created by digitalisation makes it attractive for many other organisations; however, despite the undeniable benefits, numerous manufacturing SMEs continue to struggle with adopting digital tools to create value for their business. Consequently, the level of digitalisation in the manufacturing sector lags behind that of other industries. Various maturity models exist to assess organisations’ level of digitalisation, such as SIRI, IMPULS, and DDX. These maturity models are extensively designed and utilised to assess digitalisation in larger organisations. This study applied a tailored digital capability maturity assessment tool to evaluate ten manufacturing SMEs in the United Kingdom. The objective was to develop firm-specific digitalisation roadmaps aligned with each organisation’s strategic goals and operational context. The assessment revealed diverse digital maturity profiles across the firms. Some SMEs had invested in digital infrastructure but lacked the skills or processes to generate value. In contrast, others demonstrated strong data-driven decision-making capabilities but lacked the infrastructure to scale digital initiatives. These contrasting patterns underscore the importance of a balanced digital capacity and maturity approach. As an outcome, all ten SMEs received customised digital transformation roadmaps. Notably, six firms began implementing capability-building initiatives, including investments in digital infrastructure and workforce development. These findings suggest that effective SME digitalisation requires both technological readiness and organisational alignment and highlight the need for maturity models that accommodate SME-specific constraints and strategic priorities. This study employed a digital capability maturity assessment tool.</p

Water content in pure CO₂ and CO₂-rich mixtures using the DSH analytical technique

The accurate determination of water content in equilibrium with hydrates helps to prevent operational problems related to flow assurance, and it is essential for the emerging Carbon Capture and Storage (CCS) processes for decarbonization. However, the experimental challenges associated with these measurements cause a scarcity of data. The development of the Differential Scanning Hygrometer (DSH) method has increased the number of water content reports for CO2-rich systems in equilibrium with hydrates. It monitors not absolute values but fluctuations in the water content due to the formation of ice or dew inside a temperature-controlled tube. Here, we provide experimental and modeling investigation for water content on pure CO2 and two CO2-rich mixtures (CO2+CH4 and CO2+CH4+N2) in equilibrium with hydrates: the sCPA and the SRK+EMS equations of state were used to model the obtained experimental data, both using the van der Waals-Platteeuw (vdW-P) model for the hydrate phase

A fractional partition of unity finite element method for transient anomalous diffusion problems

A fractional partition of unity finite element method is proposed for the solution of the transient anomalous diffusion equation. The Caputo integro-differential operator is employed to represent the fractional time-derivative in these problems. To approximate the Caputo fractional derivative, we propose a new numerical differentiation formula using quadratic splines. For the spatial discretization, we implement an enriched finite element method on unstructured meshes. In the present study, a category of exponential functions incorporating fractional orders is introduced as enrichment functions to refine the finite element approximation. These functions are designed to capture the fractional characteristics of the solution more effectively. By integrating these enrichment functions through the partition of unity framework, the method utilizes prior knowledge of the fractional problem, leading to a substantial enhancement in approximation accuracy while preserving the fundamental advantages of the traditional finite element method. Consequently, the proposed approach delivers precise numerical solutions even with coarse meshes and requires significantly fewer degrees of freedom compared to conventional finite element techniques. Moreover, the mesh resolution remains unaffected by variations in the fractional order, allowing for a consistent mesh structure regardless of changes in fractional parameters. Through extensive numerical simulations, we consistently verify the effectiveness of the proposed technique in achieving high levels of accuracy. This approach not only ensures reliable and precise results but also broadens the applicability of the finite element method, making it more capable of handling time-fractional transient diffusion problems that have traditionally been challenging for standard methods