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The microchannel plate (MCP) is an electron multiplier with millions of micro through-holes that must withstand strong vibrations and enormous shocks in spaceborne detectors. To ensure the reliability and robustness of the MCP in space applications, we proposed an equivalent mechanical model of the MCP to investigate its mechanical properties, since the direct creation of the finite element model using the finite element method (FEM) is not feasible. Then, we developed a test system to verify the effectiveness of the equivalent mechanical model. The results show that the error of harmonic response analysis and the test result is less than 10 %, which is acceptable. Finally, we conducted parametric studies of the MCPs and obtained the equivalent mechanical model of the MCPs with different geometric parameters. This study will help researchers to optimize the MCP for aerospace-grade detectors. [ABSTRACT FROM AUTHOR]

Abstract The diverse morphologies of 2D transition metal dichalcogenides (2D TMDs) motivate their broad potential applications in the next generation of electronic, optical, and catalytic technologies. It is advantageous to develop controllable growth techniques that afford versatility through direct manipulation of the growth parameters. A fundamental understanding of the physical mechanisms driving various growth modes is crucial for achieving the process precision necessary for obtaining reproducible morphologies in 2D TMDs. Thermodynamic and kinetic considerations are two key physical strategies. Thermodynamic strategies mainly involve the manipulation of parameters like temperature and the chemical potential of precursors to ensure the thermostability of various morphologies. Conversely, kinetic strategies, focusing on the factors, like precursor diffusion, adsorption, and desorption during the growth, also enable atomic‐level kinetics control of the resulting morphologies. Often, an interplay of both mechanisms drives the growth of a particular morphology. This review aims to provide an updated guidance for exploiting these physical strategies in the versatile technique of chemical vapor deposition. The opportunities for further exploring the control of these physical mechanisms are discussed through recent examples with an eye on unlocking the untapped potential of 2D TMDs in areas such as phase engineering and shape control for advanced applications.

Oxicam is a class of non-steroidal anti-inflammatory drugs (NSAIDs) that exhibits structural similarities to the enolic acid of 4-hydroxy-1,2-benzothiazine carboxamides. The oxicam derivatives have the ability to coordinate with different metal ions in a monodentate and bidentate fashion. The choice of ligand and reaction conditions played a key role for the synthesis of desired oxicam-based metal complexes. In this review, oxicam-based Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) transition metal complexes are being discussed. In all these complexes, the oxicams acted as N,O-coordinating chelators and stabilized metal complexes by forming six-membered ring systems. The coordination geometries of the metal complexes are dependent on the oxicam derivatives, co-ligands as well as selected metal ions. The octahedral, square pyramidal, square planar and tetrahedral geometries are concluded with the supported by electronic transitions and magnetic data of the oxicam functionalized metal complexes. The antibacterial, anticancer, and DNA interaction of the oxicam-based metal complexes have also been discussed. The antibacterial and anticancer activities indicated that some metal complexes are more potent as compared to free ligands. The DNA binding studies confirmed that the metal complexes interact with DNA via major grooves. [ABSTRACT FROM AUTHOR]

Tandem photoelectrochemical cells (PECs) are devices useful for water splitting (WS) with the production of oxygen at the photoanode (PA) and hydrogen at the photocathode (PC) by adsorbing more than 75% of the solar irradiation; a portion of the UV/Vis direct solar irradiation is captured by the PA and a diffused or transmitted IR/Vis portion by the PC. Herein, Ti-doped hematite (PA) and CuO (PC) were employed as abundant and non-critical raw semiconductors characterised by proper band gap and band edge banding for the photoelectrochemical WS and absorption of sunlight. The investigation of inexpensive PEC was focused on the scalability of an active area from 0.25 cm2 to 40 cm2 with a rectangular or square shape. For the first time, this study introduces the novel concept of a glass electrode membrane assembly (GEMA), which was developed with an ionomeric glue to improve the interfacial contact between the membrane and photoelectrodes. On a large scale, the electron–hole recombination and the non-optimal photoelectrodes/electrolyte interface were optimized by inserting a glass support at the photocathode and drilled fluorine tin oxide (FTO) at the photoanode to ensure the flow of reagents and products. Rectangular 40 cm2 PEC showed a larger maximum enthalpy efficiency of 0.6% compared to the square PEC, which had a value of 0.37% at a low bias-assisted voltage (−0.6 V). Furthermore, throughput efficiency reached a maximum value of 1.2% and 0.8%, demonstrating either an important effect of the PEC geometries or a non-significant variation of the photocurrent within the scalability. [ABSTRACT FROM AUTHOR]

This study explores the potential use of new connections to shape precast building geometries, focusing on connection performance, robotic fabrication, and foldable structural elements. Three connection types, including coupled-bolts, hinges, and steel tubes, were initially proposed and assessed in beam and portal frame geometries. In contrast, the study introduces conceptual ideas; initial experimental and numerical studies were conducted to estimate connection capacities. Robotic fabrication for connecting elements to reused concrete and converting floor elements into beams was detailed, showcasing robotic technology's performance and potential. These connections were employed in designing new precast element geometries, ranging from simple beams to multi-story buildings. Geometric properties and volume quantities of folded and opened geometries were studied using 37 CAD models. To properly discuss the joint performance reference, monolithic elements with exact dimensions were created for comparison. Despite varied connection capacity ( 38 % to 100 % ), the steel tube exhibited the most desirable performance, resembling a monolithic element with an exact size. Some proposed foldable geometries showed a significant reduction (up to 7 % ) in element dimensions to facilitate transport and construction. [ABSTRACT FROM AUTHOR]

Selective Laser Sintering (SLS) has the potential to offer a more accurate alternative to current-practice manipulation of oral dosage forms for pediatric, geriatric, and dysphagia-suffering patient groups. In order to create the best possible dosage forms for these patient groups, an in-depth look into how a dosage forms geometry impacts the overall properties is essential. In this study, the impact of geometry on SLS manufactured oral dosage forms on the tablet’s microstructure, actual-to-theoretical volume, mass deviation, disintegration, and dissolution was investigated. Three different shapes; cylinder, hollow cylinder, and conical frustum with similar surface area (SA), as well as three cylinders with different diameters, were investigated. The results indicate that the geometry has an impact on the mass uniformity, resultant volume, disintegration, and dissolution properties of the tablets. The mass uniformity analysis of the tablets provided the most variation between tablets of different sizes, with more uniformity for tablets with similar SA-to-volume ratio (SA/V). When examining the actual-to-theoretical volume of the tablets, a greater variance between the actual and theoretical volumes for shapes with higher overall SA was observed. The values found are approximately 1.05 for the three differently sized cylinders, 1.23 for the conical frustum, and 1.44 for the hollow cylinder, following this trend. Disintegration data supported a link between SA/V and average disintegration time, observed with the tablet of the highest SA/V disintegrating in 12 s and the tablet with the lowest SA/V disintegrating in 58 s. Dissolution results also indicated a strong dependence on SA/V. Hence, when novel ways to produce oral dosage form tablets become available by additive manufacturing, such as SLS, both geometry and SA/V must be taken into consideration in the tablet design process to ensure appropriate release kinetics and dosing standards.

Durante il periodo safavide a Isfahan, nell’organizzazione delle moschee si possono identificare i princìpi che hanno guidato le scelte dei progettisti per definire e realizzare i motivi decorativi. In questo articolo cerchiamo di spiegare come la religione sciita abbia influenzato l’ideazione degli apparati decorativi nelle moschee del periodo safavide a Isfahan, come in quella, ad esempio, chiamata di Shah o dell’Imam, verificando il grado di corrispondenza e sinergia tra progetto e decorazione. Le molte architetture realizzate durante il periodo safavide dal (XVI -XVIII secolo), mostrano l’ampia attività che caratterizzò il regno di Shah Abbas. Durante questo periodo, l’antico e tradizionale stile architettonico iraniano viene decisamente rinnovato; gran parte degli edifici safavidi, quali moschee, scuole e caravanserragli, vengono costruiti seguendo un impianto planimetrico che prevedeva lo sviluppo della costruzione intorno ai quattro lati di un portico centrale. Una delle caratteristiche più rilevanti delle decorazioni ascrivibili a questo periodo è l’osservanza delle regole di simmetria, raddoppio speculare, ripetizione e ordine geometrico.

The three‐dimensional arrangement of atoms in molecules is essential for understanding their properties and behavior. Traditional 2D representations and digital 3D models presented on 2D media often fall short in conveying the complexity of molecular structures. Autostereoscopic displays, often marketed as "holographic" displays, pose a potential solution to this challenge. These displays, with their multi‐view and single‐view configurations, promise to advance chemistry education and research by offering accurate 3D representations with depth and parallax. In this perspective, I delve into the possibilities and limitations of autostereoscopic displays in chemistry, discussing the underlying technology and potential applications, from research to teaching and science communication. Multi‐view autostereoscopic displays excel in facilitating collaborative work by enabling multiple viewers to simultaneously perceive the same 3D structure from different angles. However, they currently suffer from low resolution and high cost, which could limit their immediate widespread adoption. Conversely, single‐view autostereoscopic displays with eye‐tracking, while limited to one viewer at a time, provide higher resolution at a lower cost, thus suggesting that they might become the technology of the future given the balance of price to performance. Despite current limitations, autostereoscopic displays possess undeniable potential for shaping the future of chemistry education and research. [ABSTRACT FROM AUTHOR]

Doping W into Li can greatly enhance the activity of Li-ion battery. However, the structures and properties of W-doped Li clusters remain elusive. In this study, we combined the global-minimum optimization and the density-functional theory calculations to systematically explore the lowest-energy structures of WLin (n = 2–12) bimetallic clusters and found it evolves from a triangle structure to a polyhedron pyramid structure, and finally to an endohedral cluster with W atom inside. In particular, W@Li12 is identified as a superatom. The cluster exhibits an icosahedral structure with 18 valence electrons, which has a notable HOMO–LUMO gap of 1.56 eV. The ab initio molecular dynamics simulations confirm the thermal stability of this cluster. Furthermore, the infrared spectrum has two vibration peaks, corresponding to the bending vibration and stretching vibration of the tungsten–lithium bond, respectively. The UV–Vis spectrum has two absorption peaks at the excitation energy of 2–4 eV, revealing the characteristics of the orbital electron transition. This study paves the way for the study of Li–W alloy to understand its mechanism in Li-ion battery. [ABSTRACT FROM AUTHOR]

The junChS‐F12 composite method has been improved by means of the latest implementation of the CCSD(F12*)(T+) ansatz and validated for the thermochemistry of molecules containing atoms of the first three rows of the periodic table. A thorough benchmark showed that this model, in conjunction with cost‐effective revDSD‐PBEP86‐D3(BJ) reference geometries, offers an optimal compromise between accuracy and computational cost. If improved geometries are sought, the most effective option is to add MP2‐F12 core‐valence correlation corrections to CCSD(T)‐F12b/jun‐cc‐pVTZ geometries without the need of performing any extrapolation to the complete basis set limit. In the same vein, CCSD(T)‐F12b/jun‐cc‐pVTZ harmonic frequencies are remarkably accurate without any additional contribution. Pilot applications to noncovalent intermolecular interactions, conformational landscapes, and tautomeric equilibria confirm the effectiveness and reliability of the model. [ABSTRACT FROM AUTHOR]

This paper investigates the integration of multiple geometries present within a ReLU-based neural network. A ReLU neural network determines a piecewise affine linear continuous map, M, from an input space ℝm to an output space ℝn. The piecewise behavior corresponds to a polyhedral decomposition of ℝm. Each polyhedron in the decomposition can be labeled with a binary vector (whose length equals the number of ReLU nodes in the network) and with an affine linear function (which agrees with M when restricted to points in the polyhedron). We develop a toolbox that calculates the binary vector for a polyhedra containing a given data point with respect to a given ReLU FFNN. We utilize this binary vector to derive bounding facets for the corresponding polyhedron, extraction of “active” bits within the binary vector, enumeration of neighboring binary vectors, and visualization of the polyhedral decomposition (Python code is available at https://github.com/cglrtrgy/GoL_Toolbox). Polyhedra in the polyhedral decomposition of ℝm are neighbors if they share a facet. Binary vectors for neighboring polyhedra differ in exactly 1 bit. Using the toolbox, we analyze the Hamming distance between the binary vectors for polyhedra containing points from adversarial/nonadversarial datasets revealing distinct geometric properties. A bisection method is employed to identify sample points with a Hamming distance of 1 along the shortest Euclidean distance path, facilitating the analysis of local geometric interplay between Euclidean geometry and the polyhedral decomposition along the path. Additionally, we study the distribution of Chebyshev centers and related radii across different polyhedra, shedding light on the polyhedral shape, size, clustering, and aiding in the understanding of decision boundaries.

Labyrinth weirs are complex hydraulic structures. They have been widely used as a water regulator and to increase discharge in channels and spillway dams. Labyrinth weirs are an economical and effective method to pass large floods. In addition, they are used to reduce the requirements of the structural footprint. These features make them an interesting and appropriate choice to increase the capacity of discharge. Several factors affect the discharge capacity and the hydraulic performance of labyrinth weirs, including water level to crest height ratio, angle of sidewalls, apex width, conveyance channel conditions, and vertical aspect ratio. The present paper aims to summarise the most relevant knowledge of the hydraulic characteristics of the labyrinth weirs reported in previous articles. The importance of the present study is to provide a better understanding of how these weirs operate, in addition to which future studies deserve further investigation. The results demonstrated that some parameters still need further investigation. Also, energy dissipation over the labyrinth weir needs further investigation with different weir geometry. Furthermore, the results showed that common design equations did not take into account all parameters affecting labyrinth weir performance, including geometries, flow conditions, site conditions, and scale effect. In addition, machine learning techniques need further study. HIGHLIGHTS The highlights of this review article are as follows:; • The physical modelling was reviewed.; • The numerical modelling was reviewed.; • The design methods of labyrinth weirs were reviewed.; • Machine learning techniques were reviewed.; • The present review article provides a scope of future works of labyrinth weirs.;

Tandem photoelectrochemical cells (PECs) are devices useful for water splitting (WS) with the production of oxygen at the photoanode (PA) and hydrogen at the photocathode (PC) by adsorbing more than 75% of the solar irradiation; a portion of the UV/Vis direct solar irradiation is captured by the PA and a diffused or transmitted IR/Vis portion by the PC. Herein, Ti-doped hematite (PA) and CuO (PC) were employed as abundant and non-critical raw semiconductors characterised by proper band gap and band edge banding for the photoelectrochemical WS and absorption of sunlight. The investigation of inexpensive PEC was focused on the scalability of an active area from 0.25 cm2 to 40 cm2 with a rectangular or square shape. For the first time, this study introduces the novel concept of a glass electrode membrane assembly (GEMA), which was developed with an ionomeric glue to improve the interfacial contact between the membrane and photoelectrodes. On a large scale, the electron–hole recombination and the non-optimal photoelectrodes/electrolyte interface were optimized by inserting a glass support at the photocathode and drilled fluorine tin oxide (FTO) at the photoanode to ensure the flow of reagents and products. Rectangular 40 cm2 PEC showed a larger maximum enthalpy efficiency of 0.6% compared to the square PEC, which had a value of 0.37% at a low bias-assisted voltage (−0.6 V). Furthermore, throughput efficiency reached a maximum value of 1.2% and 0.8%, demonstrating either an important effect of the PEC geometries or a non-significant variation of the photocurrent within the scalability.

This study explores the potential use of new connections to shape precast building geometries, focusing on connection performance, robotic fabrication, and foldable structural elements. Three connection types, including coupled-bolts, hinges, and steel tubes, were initially proposed and assessed in beam and portal frame geometries. In contrast, the study introduces conceptual ideas; initial experimental and numerical studies were conducted to estimate connection capacities. Robotic fabrication for connecting elements to reused concrete and converting floor elements into beams was detailed, showcasing robotic technology’s performance and potential. These connections were employed in designing new precast element geometries, ranging from simple beams to multi-story buildings. Geometric properties and volume quantities of folded and opened geometries were studied using 37 CAD models. To properly discuss the joint performance reference, monolithic elements with exact dimensions were created for comparison. Despite varied connection capacity (38% to 100%), the steel tube exhibited the most desirable performance, resembling a monolithic element with an exact size. Some proposed foldable geometries showed a significant reduction (up to 7%) in element dimensions to facilitate transport and construction.

Cold Spray Additive Manufacturing (CSAM) produces freeform parts by accelerating powder particles at supersonic speed which, impacting against a substrate material, trigger a process to consolidate the CSAM part by bonding mechanisms. The literature has presented scholars' efforts to improve CSAM materials' quality, properties, and possibilities of use. This work is a review of the CSAM advances in the last decade, considering new materials, process parameters optimization, post-treatments, and hybrid processing. The literature considered includes articles, books, standards, and patents, which were selected by their relevance to the CSAM theme. In addition, this work contributes to compiling important information from the literature and presents how CSAM has advanced quickly in diverse sectors and applications. Another approach presented is the academic contributions by a bibliometric review, showing the most relevant contributors, authors, institutions, and countries during the last decade for CSAM research. Finally, this work presents a trend for the future of CSAM, its challenges, and barriers to be overcome. [ABSTRACT FROM AUTHOR]

In this paper, for a highly coupled two-stage ejector-based cooling cycle, the optimization of primary nozzle length and angle of the second-stage ejector under varied primary nozzle diameters of the second stage was conducted first. Next, the evaluation for the influence of variable back pressure on ER of the two-stage ejector was performed. Last, the identification of the effect of the variable back pressure on the key geometries of the two-stage ejector was carried out. The results revealed that: (1) with the increase of the nozzle diameter at the second stage, the ER of both stages decreased with the increases of the length and angle of the converging section of the second-stage primary nozzle; (2) the pressure lift ratio range of the second-stage ejector in the critical mode gradually increased with the increase of the nozzle diameter of the second-stage; (3) when the pressure lift ratio increased from 102% to 106%, the peak ER of the second-stage decreased, and the influence of the area ratio and nozzle exit position of the second-stage ejector on its ER was reduced; (4) with the increase of nozzle diameter of the second-stage, the influence of area ratio and nozzle exit position of the second-stage on the second-stage performance decreased; and (5) the optimal AR of the second stage decreased but the optimal nozzle exit position of the second stage kept constant with the pressure lift ratio of the two-stage ejector. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are important and widely used as antimicrobials and nanodrug carriers. The increased use of AgNPs in consumer products has raised concerns about nanosafety; for instance, AgNPs may be inhaled and translocated to the brain via olfactory neural stem cells/progenitors. While the biological effects of nanoparticle size have been widely investigated, there are little data on the effects of particle shape on cellular phenotype. Therefore, here we investigated the interactions between AgNP spheres, rods, cubes, and triangles and human plasma proteins as well as their effects on the viability of NE‐4C neural stem cells. Nanoparticles were synthesized by wet chemistry methods and characterized by UV‐vis spectroscopy, dynamic light scattering, zeta potential measurement, transmission electron microscopy, nanoparticle tracking analysis, and differential centrifugal sedimentation. NE‐4C cell viability was assessed using the MTT reduction assay, and the cellular uptake of differently shaped nanoparticles was monitored by electron microscopy. All 50 nm (in at least one dimension) AgNPs exerted toxic effects, with rods and cubes displaying greater toxicity than spheres and triangles. These cellular and physicochemical results indicate that edges on the AgNPs increase toxicity, presumably due to enhanced ion dissolution from the edges. [ABSTRACT FROM AUTHOR]

Cold Spray Additive Manufacturing (CSAM) is an emergent technique to produce parts by the additive method, and, like other technologies, it has pros and cons. Some advantages are using oxygen-sensitive materials to make parts, such as Ti alloys, with fast production due to the high deposition rate, and lower harmful residual stress levels. However, the limitation in the range of the parts' geometries is a huge CSAM con. This work presents a new conceptual strategy for CSAM spraying. The controlled manipulation of the robot arm combined with the proper spraying parameters aims to optimize the deposition efficiency and the adhesion of particles on the part sidewalls, resulting in geometries from thin straight walls, less than 5 mm thick, up to large bulks. This new strategy, Metal Knitting, is presented regarding its fundamentals and by comparing the parts' geometries produced by Metal Knitting with the traditional strategy. The Metal Knitting described here made parts with vertical sidewalls, in contrast to the 40 degrees of inclination obtained by the traditional strategy. Their mechanical properties, microstructures, hardness, and porosity are also compared for Cu, Ti, Ti6Al4V, 316L stainless steel, and Al. [ABSTRACT FROM AUTHOR]

The combination of polymer-derived ceramics and DLP 3D printing has significant advantages for manufacturing special polynary ceramics with complex structures. However, a large number of the organic components in the precursor rapidly burn out and release after evaporation during pyrolysis. This leads to structural retention issues such as sample deformation, shrinkage and cracking. The surface morphology and accuracy of the sample are greatly affected by the escape of organic matter and the release of thermal stress during the pyrolysis process. Therefore, this study employs the method of adding low-melting-point silicone oil based on the original material components. The slow burn-out process of silicone oil at a lower temperature can produce fine pores, which would aid the release of thermal stress. Additionally, it can provide channels for escape of the organic gas at high-temperature, which helps to reduce large deformation and cracking and improves the surface morphology and dimensional accuracy of the final pyrolyzed samples. The method studied in this work helps to enhance the structural retention of complex-shaped polymer-derived ceramics manufactured by 3D printing and high-temperature pyrolysis, which could be beneficial to the further mass fabrication of such ceramic products. [ABSTRACT FROM AUTHOR]

TiO2 nanotubes (TiO2NTs) are beneficial for photogenerated electron separation in photocatalysis. In order to improve the utilization rate of TiO2NTs in the visible light region, an effective method is to use Aun cluster deposition-modified TiO2NTs. It is of great significance to investigate the mechanism of Aun clusters supported on TiO2NTs to strengthen its visible-light response. In this work, the structures, electronic properties, Mulliken atomic charge, density of states, band structure, and deformation density of Aun (n = 1, 8, 13) clusters supported on TiO2NTs were investigated by DMOL3. Based on published research results, the most stable adsorption configurations of Aun (n = 1, 8, 13) clusters supported with TiO2NTs were obtained. The adsorption energy increased as the number of Au adatoms increased linearly. The Aun clusters supported on TiO2NTs carry a negative charge. The band gaps of the three most stable structures of each adsorption system decreased compared to TiO2NTs; the valence top and the conduction bottom of the Fermi level come mainly from the contribution of 5d and 6s-Au. The electronic properties of the 5d and 6s impurity orbitals cause valence widening and band gap narrowing. [ABSTRACT FROM AUTHOR]

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In this paper, for a highly coupled two-stage ejector-based cooling cycle, the optimization of primary nozzle length and angle of the second-stage ejector under varied primary nozzle diameters of the second stage was conducted first. Next, the evaluation for the influence of variable back pressure on ER of the two-stage ejector was performed. Last, the identification of the effect of the variable back pressure on the key geometries of the two-stage ejector was carried out. The results revealed that: (1) with the increase of the nozzle diameter at the second stage, the ER of both stages decreased with the increases of the length and angle of the converging section of the second-stage primary nozzle; (2) the pressure lift ratio range of the second-stage ejector in the critical mode gradually increased with the increase of the nozzle diameter of the second-stage; (3) when the pressure lift ratio increased from 102% to 106%, the peak ER of the second-stage decreased, and the influence of the area ratio and nozzle exit position of the second-stage ejector on its ER was reduced; (4) with the increase of nozzle diameter of the second-stage, the influence of area ratio and nozzle exit position of the second-stage on the second-stage performance decreased; and (5) the optimal AR of the second stage decreased but the optimal nozzle exit position of the second stage kept constant with the pressure lift ratio of the two-stage ejector.

Cold Spray Additive Manufacturing (CSAM) is an emergent technique to produce parts by the additive method, and, like other technologies, it has pros and cons. Some advantages are using oxygen-sensitive materials to make parts, such as Ti alloys, with fast production due to the high deposition rate, and lower harmful residual stress levels. However, the limitation in the range of the parts’ geometries is a huge CSAM con. This work presents a new conceptual strategy for CSAM spraying. The controlled manipulation of the robot arm combined with the proper spraying parameters aims to optimize the deposition efficiency and the adhesion of particles on the part sidewalls, resulting in geometries from thin straight walls, less than 5 mm thick, up to large bulks. This new strategy, Metal Knitting, is presented regarding its fundamentals and by comparing the parts’ geometries produced by Metal Knitting with the traditional strategy. The Metal Knitting described here made parts with vertical sidewalls, in contrast to the 40 degrees of inclination obtained by the traditional strategy. Their mechanical properties, microstructures, hardness, and porosity are also compared for Cu, Ti, Ti6Al4V, 316L stainless steel, and Al.

Rapid advances in additive manufacturing have kindled widespread interest in the rational design of metamaterials with unique properties over the past decade. However, many applications require multi‐physics metamaterials, where multiple properties are simultaneously optimized. This is challenging since different properties, such as mechanical and mass transport properties, typically impose competing requirements on the nano‐/micro‐/meso‐architecture of metamaterials. Here, a parametric metamaterial design strategy that enables independent tuning of the effective permeability and elastic properties is proposed. Hyperbolic tiling theory is applied to devise simple templates, based on which triply periodic minimal surfaces (TPMS) are partitioned into hard and soft regions. Through computational analyses, it is demonstrated how the decoration of hard, soft, and void phases within the TPMS substantially enhances their permeability–elasticity property space and offers high tunability in the elastic properties and anisotropy at constant permeability. Also shown is that this permeability–elasticity balance is well captured using simple scaling laws. The proposed concept is demonstrated through multi‐material additive manufacturing of representative specimens. The approach, which is generalizable to other designs, offers a route towards multi‐physics metamaterials that need to simultaneously carry a load and enable mass transport, such as load‐bearing heat exchangers or architected tissue‐substituting meta‐biomaterials. [ABSTRACT FROM AUTHOR]

This paper describes the experience of a three-day workshop at the end of the Visual Communication and Design course, in the first year of the Sciences of Primary Education degree course. The days of full immersion turned into a lively and creative “happening” during which communication and representation strategies for children were put into practice. The activities of painting, comics, photography, art and geometry were combined and integrated in order to experiment with reading images and to learn how to compose with them. At the end of the workshop, an exhibition of the final works was held, open to pre-schools and primary schools.

Geometry optimization of the mixed SinRe (n=12, 16, 20, 24, 28, 32, 36, and 40) cages with doublet, quartet, and sextet spin configurations is carried out systematically at the UHF/LanL2DZ level. Equilibrium structures, total energies, and stabilities of Re@Sin cages are presented and discussed. The calculated results show that all Re@Sin cages of highest symmetry undergo slight distortion into much more stable structures of lower symmetry. The Re atom in the Re@Sin (n=12, 16, 20, 24, 28, 32, 36, and 40) cages deviates from the cage center site of Sin fullerenes. Charge-transfer between Re and Si atoms makes a contribution to the stability of the Sin fullerenes; In addition, the relative stability is discussed, the most stable geometry is assigned.

TiO2 nanotubes (TiO2NTs) are beneficial for photogenerated electron separation in photocatalysis. In order to improve the utilization rate of TiO2NTs in the visible light region, an effective method is to use Aun cluster deposition-modified TiO2NTs. It is of great significance to investigate the mechanism of Aun clusters supported on TiO2NTs to strengthen its visible-light response. In this work, the structures, electronic properties, Mulliken atomic charge, density of states, band structure, and deformation density of Aun (n = 1, 8, 13) clusters supported on TiO2NTs were investigated by DMOL3. Based on published research results, the most stable adsorption configurations of Aun (n = 1, 8, 13) clusters supported with TiO2NTs were obtained. The adsorption energy increased as the number of Au adatoms increased linearly. The Aun clusters supported on TiO2NTs carry a negative charge. The band gaps of the three most stable structures of each adsorption system decreased compared to TiO2NTs; the valence top and the conduction bottom of the Fermi level come mainly from the contribution of 5d and 6s-Au. The electronic properties of the 5d and 6s impurity orbitals cause valence widening and band gap narrowing.

A glossary of commonly used terms related to the geometric forms and geological settings of basement highs is presented to assist cross‐disciplinary understanding, qualifying prefixes for the term basement are discussed and a scheme for characterising basement highs is presented. This scheme is designed to standardise, and to add rigour to, description of basement highs. It will thereby enhance basement high comparisons and assist understanding of basement highs across technical disciplines. The scheme enables systematic characterisation of: the geometry of a basement high; the lithologic units and structures in, above and around it; timings; tectonics and origins of the basement high and play elements relating to resource prospectivity. Use of this scheme is demonstrated using the southern Rona Ridge (West of Shetland, UK Continental Shelf). The tectonic, isostatic, erosional and stratigraphic processes that form basement highs are also discussed, and examples in proven petroleum systems are presented. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterostructure, vertically assembled by two kinds of two-dimensional layered materials with extraordinary electronic and optical properties, has emerged as an interesting candidate in the applications of electronics and optoelectronics. It is known that vacancies are crucial in determining the physical properties of materials, and always exist in the materials during the process of actual experimental preparations and can be artificially introduced. In the present work, the structures and electronic properties of a black phosphorus/molybdenum disulfide (BP/MoS2) vdW heterostructure with P atom vacancies are investigated via first principles calculations. Based on the structural symmetry, two types of heterostructures with single-atom vacancy and three types of heterostructures with diatomic vacancies are constructed. It is found that the presence of a single P atom vacancy leads to the transformation from semiconductor to metal in the BP/MoS2 heterostructure, which is mainly due to the contribution of the remaining P atomic p orbitals based on analyses of the partial density of states (PDOS). On the other hand, the heterostructures with diatomic P atom vacancies still maintain their pristine semiconductor features, along with a decrease in their bandgap value. In addition, the plane electrostatic potential indicates that the introduction of P atom vacancy defects causes a change in the electrostatic potential of the BP atomic layer, resulting in asymmetric electrostatic potential on both sides of the BP layer. Finally, it is interesting to note that the accumulation-depletion of electrons occurs around the vacancy, but also partially emerges at the MoS2 layer. Our results provide the possibility for the application of 2D-vacancy-defect heterostructure systems. [ABSTRACT FROM AUTHOR]

Ligand influence on the structural, electronic and optical properties of neutral Au 13 L clusters, where L = NH 3 , N (CH 3) 3 , PH 3 , P (CH 3) 3 , SCH 3 , SCH 2 Ph , SCH (CH 3) NH 2 , SCH (CH 3) Cl , SPh, SPhCH 3 , SPhCOOH and SeCH 3 , which has been investigated using density functional theory and its time-dependent approach. The analysis of the electronic stabilities reveals that the Au 13 SCH (CH 3) Cl and Au 13 NH 3 are the most stable among the other clusters of the thiolate or selenolate and of the phosphine or amine-ligated groups, respectively. The ligand effect on the optical absorption spectra of Au 13 L is relatively small, in which the main change is observed in the oscillator strength of the highest energy peak. [ABSTRACT FROM AUTHOR]

As an interdisciplinary manufacturing technique, microfluidics has attracted great attention in fields such as food structuring, chemical analysis, biomedicine, and biological testing. In particular, significant efforts have been recently made to design food structures via microfluidics, starting with its fundamental principles, thus contributing to developing next-generation, high-quality food products with satisfactory properties and attributes. This review first introduces the fundamental principles of microfluidic systems, and then focuses on their applications in the fabrication of different food structures, including emulsions (via shear-driven, spontaneous, or wettability-controlled emulsification), foams, microparticles (biopolymers-based and liposomes), and microgels (induced by temperature or ions). The upscaling strategies for microfluidic devices and challenges for application in the food industry are also reviewed. Despite such advances, it is still vital to further understand the flowing, droplet formation, and structuring of multi-component food matrices and the related developments of cost-effective microfluidic devices to meet practical requirements. [Display omitted] • Basic principles of microfluidics and its application in food structuring reviewed. • Microfluidic dimensionless numbers affect fluid flow regime and droplet formation. • Microfluidic system geometry affects fluid flow regime and droplet formation. • Microfluidics useful for structuration of emulsions, microparticles and microgels. [ABSTRACT FROM AUTHOR]

The effect of different thermal conditions on battery performance has been evaluated by computer simulation through a thermal model coupled to the electrochemical model. Three different active materials, lithium cobalt oxide, LiCoO 2 , lithium iron phosphate, LiFePO 4 and lithium manganese oxide, LiMn 2 O 4 , were evaluated together with two battery geometries: conventional and interdigitated. The delivered capacity of the different active materials and both geometries were thus obtained as a function of the scan rate and correlated with the produced reversible, reaction, ohmic and total heat. For isothermal conditions, the highest capacity is obtained for LiCoO 2 , being 739,31 Ahm−2 at 1C for the conventional geometry. Further, battery performance as a function of the scan rate is independent of the geometry and similar for the different active materials. Under adiabatic conditions and independent geometry, LiFePO 4 produces lower heat in the discharge process, the temperature ranging from 298 K to 308.9 K when the battery operates up to 500C for and interdigitated geometry with eight digits, which is critical for improving battery safety. This fact is also confirmed by the ohmic heat value along the cathode at the rate of 300C, which is 42700 W m−3, 118000 W m−3 and 69000 W m−3 for LiFePO 4 , LiMn 2 O 4 and LiCoO 2 , respectively, for a conventional geometry as at a time of 50s of battery operation. Thus, it is demonstrated how battery geometry and the intrinsic parameters of the active materials affect the heat generated by the batteries and, considering the balance between cycle performance and thermal properties, the best active material for improved battery safety and performance is LiFePO 4. [ABSTRACT FROM AUTHOR]

Abstract The advancements in software and hardware technologies provide opportunities for solar shading systems to function dynamically within their context. This development has helped dynamic shading systems respond to variable environmental parameters such as sun angles and solar insolation. However, the technical understanding of system design, mechanism and controlling methods presents a challenge for architects and designers. Therefore, this study aims to review the current applications and trends of dynamic shading systems to clarify the potentials and limitations in enhancing system performance based on integrated design objectives. This study assessed several systems on the basis of a critical review to identify different models, applications and methodologies. This study is divided into two main sections: (i) design elements and platforms that engage with specific methods in creating a dynamic shading system and (ii) evaluation strategies to examine system performance. The systems were investigated based on the multiplicity and integration of the parameters involved through various components, such as architectural, mechanical, operational and automation components. The review analysed various studies on the following two bases: (1) geometric-based analysis, which distinguishes between simple and complex shading models, and (2) performance-based analysis, which assesses the shading systems based on two groups of methodologies, namely, theoretical and experimental. The outcome of the review reflects a clear classification of shading models and a comprehensive analysis of their performance. This study generally provides a systematic framework for architects based on thorough research and investigation. Finally, the study introduced several findings and recommendations to improve the performance of dynamic shading systems. Highlights • A critical review of the current applications and trends of dynamic shading systems is presented. • A research concept to investigate dynamic shading systems is developed. • A clear systematic framework for architects is proposed. [ABSTRACT FROM AUTHOR]

Abstract In this study, the detonation propagation characteristics of stoichiometric CH 4 -2H 2 -3O 2 mixture are investigated comprehensively in a round tube with an inner diameter of 90-mm and 6-m in length. Three different orifice plates with the blockage ratios (BR) of 0.7 and 0.8 including circular, triangular and square orifice, are considered for the first time to investigate the effect of obstacle geometries on the detonation evolution. Eight high-speed piezoelectric pressure transducers are mounted on the outer wall to obtain the detonation velocity while the smoked foil technique is adopted to record the detonation cellular patterns. The results indicate that well within the limit, the detonation can propagate at about the theoretical CJ velocity (V CJ). Near the limit, the velocity deficit is sharply enhanced but the detonation still can propagate at about 0.6V CJ , which seems to be a universal phenomenon before the failure of the detonation. In the smooth tube, a sudden velocity drop and the single-headed spin can be seen near the critical condition, and the critical pressure (P c) is 3 kPa. In the tube filled with obstacles, the effect of obstacle geometries on the detonation transmission can be ignored approximately for the BR = 0.7 case, and the critical pressures are increased to 7, 7 and 10 kPa, respectively. In the case of BR = 0.8, the effect of the orifice plates structures on the detonation propagation becomes more significant. The square orifice has the most serious impact on the detonation transmission, followed by triangular ones and the round hole has the least impact. The critical pressures are sharply enhanced to 10, 12 and 18 kPa, respectively. Finally, the effective diameter (d eff) and the characteristic parameter (L) are introduced to analyze the critical condition of the detonation propagation. The critical condition can quantified as d eff /λ > 1 and L/λ > 7 where λ is the detonation cell size. Highlights • Effect of obstacle geometries on the detonation propagation is investigated. • Near the limit, the detonation velocity deficit is explored. • The mechanisms of detonation propagation are described. • Analysis of the critical condition of detonation propagation are performed. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the effect of shrinkage on the heat-transfer-controlled processes of tabular (slab), cylindrical, and spherical geometries. A model is used to simulate the product yield, pyrolysis time, particle size, specific heat capacity, and Biot number for analyzing the effect of shrinkage on different geometries. Spherical, tabular, and cylindrical biomass briquettes with an equivalent diameter of 0.0002–0.1 m are used for simulation. The proposed model is validated using the experimental product yield data obtained from the two-stage gasifier in this study and the experimental data reported in the literature. Thermal waves are observed with an increase in particle size. The tabular geometry exhibits the maximum number of thermal waves, whereas the spherical geometry exhibits the least number of thermal waves. The shrinking effect favors the formation of volatiles and gases, whereas the nonshrinking effect favors the formation of char. The product yield remains unchanged with an increase in the specific heat capacity and Biot number. However, the production of volatiles and gases increases in the order sphere > cylinder > tabular, whereas the production of char increases in the order tabular > cylinder > sphere for the entire specific heat capacity range. Highlights • Yield of volatiles and gases is higher for shrinking than nonshrinking particles. • Shrinkage has a significant effect on the pyrolysis time of thick particles. • Shrinking particles requires less pyrolysis conversion time than nonshrinking. • Yield of volatiles and gases increases in the order sphere > cylinder > tabular. • Yield of char increases in the order tabular > cylinder > sphere. [ABSTRACT FROM AUTHOR]

In many nuclear reactor physics texts (excluding Elmer Lewis’s recent text however), “Chapter 5” is dedicated to diffusion theory; hence, the title of this submission. Here, we will investigate analytical solutions to the most basic form of the monoenergetic 1D stationary diffusion equation. The intuitive approach taken radically departs from the usual method of solving the diffusion equation. In particular, we consider a general setting such that the method accommodates all solutions to the monoenergetic diffusion equations in 1D plane and curvilinear geometries. This is not your father’s diffusion theory and, for this reason, we anticipate it will eventually become the classroom standard.

Within certain categories of geometric shapes, prototypical exemplars that best characterize the category have been evidenced. These geometric prototypes are classically identified through the visual and haptic perception or motor production and are usually characterized by their spatial dimension. However, whether prototypes can be recalled through the auditory channel has not been formally investigated. Here we address this question by using auditory cues issued from timbre-modulated friction sounds evoking human drawing elliptic movements. Since non-spatial auditory cues were previously found useful for discriminating distinct geometric shapes such as circles or ellipses, it is hypothesized that sound dynamics alone can evoke shapes such as an exemplary ellipse. Four experiments were conducted and altogether revealed that a common elliptic prototype emerges from auditory, visual, and motor modalities. This finding supports the hypothesis of a common coding of geometric shapes according to biological rules with a prominent role of sensory-motor contingencies in the emergence of such prototypical geometry. [ABSTRACT FROM AUTHOR]