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Hollow microspheres with open windows on the shells have shown significant potential in adsorption, catalysis, and drug delivery fields, owing to their low density, large interior volume, high specific surface area, and abundant availability of adsorption sites. However, creating open hollow spheres with structurally stable and entirely organic‐functionalized surfaces remains a challenge. Herein, we fabricated polysilsesquioxane open hollow spheres using trialkoxysilane containing mercaptopropyl groups under vigorous stirring, employing polystyrene microspheres as a template. Various reaction parameters were explored, revealing stirring speed as the key factor influencing the morphology and openness of the microspheres. By examining the morphology of intermediate products at different reaction times, we proposed a step‐growth mechanism for microsphere formation. The resulting materials exhibited high adsorption capacity and selectivity towards Hg2+ and Pb2+, attributed to the presence of thiol groups and the open‐hollow structure. Our approach provides a robust method for producing open hollow materials with functionalized surfaces, offering potential applications in the adsorption field. [ABSTRACT FROM AUTHOR]

An open type of microchannel with diamond pin fins (OM-DPFs) is introduced for the cooling of high-performance electronic chips. For a Reynolds number (Re) of 247~1173, a three-dimensional model is established to explore the hydrothermal properties of the OM-DPF and compare it to traditional heat sinks with closed rectangular microchannels (RMs), heat sinks with open microchannels (OMs), and the results in the existing research. Firstly, the synergy between tip clearance and pin fins on the hydrothermal properties is discussed. Secondly, the entropy production principle is adopted to analyze the irreversible losses for different heat sinks. Lastly, the total efficiencies of different heat sinks are assessed. The RMs present the worst heat transfer with the lowest friction loss. For the OMs, the temperature and pressure drop are decreased slightly compared to those of the RMs, and the irreversible loss is reduced by 4% at Re = 1173 because of the small tip clearance. But the total efficiency is lower than that of the RMs because the pressure drop advantage is offset by the weak heat transfer. For the OM-DPF, the combined structure has a noticeable impact on the multiple physical fields and hydrothermal characteristics, which present the best thermal performance at the cost of the highest friction loss. The irreversible loss of heat transfer in the OM-DPF is reduced obviously, but the friction irreversible loss significantly increases at high Re values. At Re = 429, the total entropy production of the OM-DPF is reduced by 47.57% compared with the RM. Compared to the OM and the single-pin fin structure in the literature, the total efficiency of the OM-DPF is increased by 14.56% and 40.32% at Re = 614. For a pump power of 0.1 W, the total thermal resistance (Rth) of the OM-DPF is dropped by 23.77% and 21.19% compared to the RM and OM. For a similar Rth, the pump power of the combined structure is 63.64% and 42.86% lower than that of the RM and OM. Thus, the novel combined heat sink can achieve efficient heat removal while controlling the energy consumption of liquid cooling systems, which has bright application prospects. [ABSTRACT FROM AUTHOR]

An open type of microchannel with diamond pin fins (OM-DPFs) is introduced for the cooling of high-performance electronic chips. For a Reynolds number (Re) of 247~1173, a three-dimensional model is established to explore the hydrothermal properties of the OM-DPF and compare it to traditional heat sinks with closed rectangular microchannels (RMs), heat sinks with open microchannels (OMs), and the results in the existing research. Firstly, the synergy between tip clearance and pin fins on the hydrothermal properties is discussed. Secondly, the entropy production principle is adopted to analyze the irreversible losses for different heat sinks. Lastly, the total efficiencies of different heat sinks are assessed. The RMs present the worst heat transfer with the lowest friction loss. For the OMs, the temperature and pressure drop are decreased slightly compared to those of the RMs, and the irreversible loss is reduced by 4% at Re = 1173 because of the small tip clearance. But the total efficiency is lower than that of the RMs because the pressure drop advantage is offset by the weak heat transfer. For the OM-DPF, the combined structure has a noticeable impact on the multiple physical fields and hydrothermal characteristics, which present the best thermal performance at the cost of the highest friction loss. The irreversible loss of heat transfer in the OM-DPF is reduced obviously, but the friction irreversible loss significantly increases at high Re values. At Re = 429, the total entropy production of the OM-DPF is reduced by 47.57% compared with the RM. Compared to the OM and the single-pin fin structure in the literature, the total efficiency of the OM-DPF is increased by 14.56% and 40.32% at Re = 614. For a pump power of 0.1 W, the total thermal resistance (Rth) of the OM-DPF is dropped by 23.77% and 21.19% compared to the RM and OM. For a similar Rth, the pump power of the combined structure is 63.64% and 42.86% lower than that of the RM and OM. Thus, the novel combined heat sink can achieve efficient heat removal while controlling the energy consumption of liquid cooling systems, which has bright application prospects.

This study focuses on collapsible soil from hyper-arid regions in the south of Algeria (Zeribet El Oued, Biskra). A physical characterization of the studied soil was performed which revealed that the soil samples are loess. After this, an experimental study was done on the influence of the sodium silicate solution (Na2SiO3) at different doses on the collapse potential (CP) and the microstructure of the material. The microstructure investigation was made through a scanning electron microscope (SEM) observation.The main results of this study show that the treatment of collapsible soil with sodium silicate has led to a significant reduction of the collapse potential, exceeding 87%. An effective treatment is obtained with a sodium silicate solution at the optimal dose of 0.8 mol.L−1. The SEM observations have revealed micro-structural transformations which are correlated to changes to geotechnical behavior. [ABSTRACT FROM AUTHOR]

The design of efficient and sustainable platinum-based catalysts is the key to developing direct alcohol fuel cells. Here, we designed highly open, one-dimensional Pt–Ni architectures with controllable wall thickness by selectively etching Pt–Ni nanowires. Pt atoms of both the inner and outer Pt–Ni architectures can participate in the electrochemical process, dramatically increasing the number of active sites and resulting in excellent alcohol electrooxidation performance. The obtained Pt1Ni5-M architecture with an ultrathin wall of 1.18 nm and a more open structure shows the best performance. The methanol oxidation reaction and ethanol oxidation reaction mass activities of Pt 1 Ni 5 -M are 7.4 (1.93 A/mg Pt) and 4.6 (0.96 A/mg Pt) times higher than that of Pt/C, respectively. After 3600s chronoamperometry tests, these Pt–Ni architectures also show improved durability with limited decay. This simple strategy inspires us to create more suitable catalysts with open structures for direct alcohol fuel cells. One-dimensional porous PtNi architectures with controllable wall thickness, particularly Pt 1 Ni 5 -M with subnanometer walls, significantly boosted platinum atom utilization, resulting in excellent alcohol oxidation performance. [Display omitted] • A novel porous one-dimensional PtNi architecture with controllable wall thickness and high openness was designed. • The wall thickness of Pt 1 Ni 5 -M can be controlled in a sub-nanometer range. • PtNi architectures greatly improve the utilization rate of Pt atoms and increase alcohol electrooxidation activity. • The alcohol electrooxidation activity trends of Pt 1 Ni x -M catalysts were negatively correlated with the wall thickness. [ABSTRACT FROM AUTHOR]

The exploitation of non noble metal oxygen evolution reaction (OER) electrocatalysts with tuneable electronic structures and chemical compositions is an effective way to improve water splitting, which is of great significance to the development of clean energy. Here, we report a zirconium-induced transition metal phosphide supported by nitrogen-doped carbon fiber (P–CoFeZr/NCBC) as an efficient electrocatalyst for the OER. The electrocatalyst is produced in situ on the surface of nitrogen-doped carbon fibers to form an open structure, achieving a high concentration of active sites. Additionally, the electronic structure is modified through the introduction of zirconium to increase the intrinsic activity of the electrocatalyst. These phenomena greatly enhance the oxygen evolution activity of the electrocatalyst. In alkaline media, P–CoFeZr/NCBC exhibits excellent catalytic activity and fast kinetics, with overpotentials and Tafel slopes of 300 mV and 51 mV/dec at 10 mA/cm2, and displays excellent long-term stability for more than 24 h at 50 mA/cm2. • N-doped carbon fibers loaded with Zr-induced bimetallic phosphides was synthesized. • The introduction of Zr improves the intrinsic activity of the electrocatalyst. • Abundant active sites in favor of OER are produced through N-doped carbon fibers. • P–CoFeZr/NCBC delivers OER performance of 300 mV and 51 mV/dec at 10 mA/cm2. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to develop a non-homogeneous NDEA model for measuring the efficiency of a mixed network with an open structure at each stage, interlayer connections, and uncertainties in inputs, outputs, and intermediate processes. Design/methodology/approach: To model the problem, a new model has been proposed first to determine the efficiency of each layer, based on the average weight of the layers. Then, the model has been developed to calculate the total efficiency. The Bertismas and Sim approach has been used to consider the uncertainty of inputs, outputs, and intermediate processes. Pistachio orchards in Yazd province have been selected as a case study, and relevant data of 10 cities in the Yazd province has been collected from the Agricultural Jihad Organization of Yazd province. Findings: The results indicated that with increasing the deviation in uncertain network data from 0.01 to 0.1, the average total efficiency decreased from 0.933 to 0.915. Such a reduction was also observed in the efficiency score of each of the DMUs. Reducing the average levels of efficiency and tightening the constraints on the proposed models reduced the number of units on the Performance boundary and eliminated the need to use super-efficient models to re-evaluate the efficiency. In other words, the computation of the total efficiency of decision-making units and sub-layers was enhanced. Research limitations/implications : The proposed approach was developed based on the model of Charans et al. (1978). As a limitation, the weighted sum of the outputs was less than or equal to the weighted sum of the inputs. The proposed model can be developed further to include other factors, such as undesirable outputs. Practical implications: Findings can provide a more accurate understanding of the performance of the components of decision-making units to managers and decision-makers. This study highlights the usefulness of the proposed models as a decision tool in agricultural units. Social implications: The developed models can be used in various social contexts. According to the case study, it is overemphasized that water resources management is significantly important for Yazd as a province located in an arid and desert region. Therefore, increasing the efficiency of orchards by identifying and improving inefficient processes, can lead to helpful-agricultural consequences in this province. Originality/value: While many studies have been conducted in the field of NDEA, this is the first study in the field of open non-homogeneous mixed networks considering uncertainty in all data, simultaneously. [ABSTRACT FROM AUTHOR]

In order to facilitate widespread commercialization of proton‐exchange membrane fuel cells (PEMFCs), the synthesis of advanced catalysts toward oxygen reduction reaction with high activity and stability is essential. Here, we report the synthesis of strongly coupled porous Pt nanospheres /three‐dimensional graphene (P−Pt @3DG) hybrid materials through a facile strategy. The P−Pt @3DG displays an excellent oxygen reduction reaction (ORR) performance with the mass activity of 0.542 A/mgPt and specific activity of 0.976 mA/cm2 at 0.9 V vs. RHE, respectively, which are 4.0‐ and 3.7‐ times higher than those of commercial Pt/C catalysts. More importantly, high stability with only 5.35 % loss after 10,000 cycles is achieved. The superior performance of P−Pt @3DG is mainly attributed to the open structure of porous Pt spheres, which exposes the internal Pt atoms with an ultrahigh Pt utilization. Moreover, the 3D graphenes possess an open and interconnected porous structure and allow efficient charge and mass transfer. Besides, this synthetic method is suitable for large scale production, which is highly applicable to the commercialization of PEMFCs. [ABSTRACT FROM AUTHOR]

Since the financial crisis of 2008, architecture must face growing conditions of instability. This rekindles the necessity to integrate the parameter of uncertainty into architectural design much like the concerns developed by the radical architects of the 1960s. At that time, these architects associated with megastructures challenged the opposites: fix/transient, permanent/ephemeral, primary/secondary structure, indeterminate/determinate. They raised the questions of uncertainty, instability over time, and gave shape to this condition. Their predecessors inside Team X introduced concepts like the ‘aesthetics of change’ (Smithsons), the ‘open form’ (Hansen), ‘open aesthetic’ (Voelcker) and developed architectural theories regarding indeterminacy and fragmentation. Out of a synthesis of this theoretical background, we propose to withdraw a conceptual tool with which we review the approach of two contemporary architectural offices, particularly concerned by the question of indeterminacy, uncertainty, open aesthetics and open structure in their achievements. Doing so, we aim to provide insights of what can constitutes a legacy out of megastrucuralist theory and identifies conceptual shifts.

The method of moments (MoM) is the primary numerical method for electromagnetic (EM) analysis by integral equation approach. The Nyström method (NM) has rapidly developed in recent years and could become a strong competitor or alternative to the MoM. The NM is a kind of point-matching method (PMM), but they are actually different. The NM uses a quadrature rule to select matching points within an element while the PMM can randomly choose the matching points. The used quadrature rule allows the NM to transform a continuous integral over a small domain into a discrete summation, leading to a direct evaluation of integrands to generate far-interaction matrix entries. In contrast, the PMM has to rely on numerical integrations to evaluate matrix entries. We propose a hybrid scheme by combining the merits of the two methods and use it to solve EM scattering by open structures, which have an abnormal EM behavior. Numerical examples are presented to illustrate the scheme and its good performance has been verified. [ABSTRACT FROM AUTHOR]

• Particle-size effects on aeolian deposition and sediment structure were examined. • Two distinct structures form during air-fall deposition as particle sizes vary. • The relevance between interparticle forces and gravity control structure formation. • A dimensionless granular bond number Bo captures the relevance of governing forces. • Open and collapsible structures form due to special accumulation behavior at Bo < 10. Aeolian deposition is significant to the landscape formation on Earth and even other planetary bodies. Particle size controls the transport distance of particles. However, the understanding of particle-size effects on the structure and mechanical behavior of aeolian accumulations remains limited. We investigate the effect of particle size on the structure and collapse of aeolian sediments by one-dimensional compression and collapse tests following the initial air-fall deposition of particles of various sizes from sand to fine silt. Results reveal that the relevance between interparticle forces and gravity controls the formation of two distinct sediment structures as the particle size varies. A loose structure with a packing density close to the simple cubic packing forms for sands and is not collapsible. An open structure with higher porosity forms as particle size becomes smaller. The structure can stack vertically. The stacking height, porosity, and collapsibility increase as particle size decreases. A dimensionless granular bond number Bo captures the relevance between van der Waals forces and gravity. A threshold particle size corresponding to Bo = 10 is identified, below which open and collapsible structures form. The structure forms due to distinctive accumulation behavior. Particle interaction forces create porous aggregates, stabilize the aggregate as it contacts the deposit, and retain open pores. The effect of fine particles on properties of deposited mixtures is also analyzed. Results are relevant to understanding the formation of collapsible aeolian deposits on Earth and may contribute to the estimation of the physical properties of aeolian sediments on other planetary bodies. [ABSTRACT FROM AUTHOR]

We present acoustic metasurfaces to achieve high noise reduction for an open structure, which refers to a structure with openings, by manipulating complex impedances along unit cells called impedance tiles. These acoustic metasurfaces are applied to inner walls of the open structure to suppress noise emanating through openings. Each impedance tile is made up of subwavelength Helmholtz resonators (HRs), and its effective impedance is tuned to minimize the noise level outside the open structure at an arbitrary target frequency by adjusting the geometrical parameters of those HRs. Rather than absorbing incident waves, the proposed metasurfaces significantly affect the magnitude and phase of scattered waves, causing the sound energy to be trapped near their surfaces and dissipated by visco-thermal losses in narrow orifices of the impedance tiles. As a result, the metasurfaces enable more effective noise reduction for the open structure compared to impedance-matching conditions, which absorb sound waves impinging on the surface. Experimental results show that the sound pressure level reduction exceeding 12.6 dB is verified for a single source at a target frequency of 360 Hz with λ /31-thick metasurfaces fabricated via three-dimensional printing. Furthermore, we demonstrate that the proposed metasurfaces are also useful in reducing noise when the number of target frequencies is more than one or when multiple sources are distributed in different locations, thereby offering a potential solution for noise reduction in a wide range of mechanical systems with open structures. [ABSTRACT FROM AUTHOR]

The gradual retardation of heterogeneous interface reactions during extended cycling results in significant capacity loss, particularly in the initial few cycles. This is due to the inhomogeneous distribution and structural degradation of heterointerfaces. Currently, a range of atomic-level tuning strategies are employed to enhance the intrinsic transfer characteristics for sodium-ion batteries (SIBs). Herein, the defect-rich single-phase ternary tin sulfide selenide (SnSe 1. 33 S 0.67) anode is constructed via favorable heteroatom(S) introducing. Such a defective open structure employed as anodes for SIBs, delivers a superior rate performance of 452.3 mAh g−1 at 5.0 A g−1, and excellent cycling stability, with a capacity retention of 535.8 mAh g−1 after 500 cycles at 1.0 A g−1. The exceptional performance is attributed to the rapid diffusion of ions/electrons through lattice defects and heteroatom coexistence, as well as the high tolerance for volume changes resulting from optimized phase transition modes and enhanced structural rigidity, as demonstrated by experimental results and density functional theory (DFT) calculations. Through the heteroatoms injection strategy, this work offers deeper insights into the correlation between precise regulation of internal defects and superior storage performance in SIBs. [ABSTRACT FROM AUTHOR]

Increased knowledge on the factors that affect emissions from open-sided dairy buildings may lead to an improvement of the mitigation strategies. In this study, ammonia (NH3) and methane (CH4) emissions were assessed in an open dairy barn in a hot Mediterranean climate at different managements of the cooling system, as well as the influence of environmental and animal-related parameters on daily emissions. Measurements of gas concentrations and micro-climatic parameters were carried out in a cubicle free-stall dairy barn located in the province of Ragusa (Italy) in two weeks of 2016 characterised by similar climatic conditions in the warm period. Emissions of NH3 and CH4 were estimated through the application of the carbon-dioxide (CO2) mass balance method. Data collected were organised in specific datasets to carry out different statistical analyses on gas emissions depending on selected parameters for the two weeks with a different management of the cooling system. The results showed higher NH3 emissions and lower CH4 emissions in W1 than those in W2. The variability in gas emissions was related to the effect of temperature humidity index (THI) (p < 0.001) and cow behaviour (p < 0.01). The highest emissions were recorded during the cleaning procedures for both NH3 (p < 0.001) and CH4 (p < 0.001), whereas the lowest emissions were recorded during the central hours of the day.

The article starts from an interpretation of the famous review of James Joyce’s Ulysses by Carl Gustav Jung called “Ulysses: A Monologue”. It focuses mainly on the comparison of the semiological assumptions of the two authors. Although both are aware of the principle of openness and fluidity of the text, it is evident, that their hypotheses, submitted to justify this view, do not have the same efficiency. The article can be also read as an attempt to articulate the so called „serial method“, i. e. the Deleuzian critique of the concept of representation from the Logic of Sense. From this point of view, the article could be considered a contribution to the poststructuralist discussion of the concept of sense.

A facile one-pot method using molten salt medium is developed to fabricate an open structured N-doped carbon (ONC) derived from biomass. SEM and TEM show the ONC is made up of interconnected thin amorphous carbon layers. N 2 isotherm shows that ONC has hierarchical porous structure with a high specific surface area of 1893.5 m 2 g − 1 . Compared to commercial Pt/C (20 wt%), the ONC has comparable ORR activity and better durability. Due to its high ORR activity and durability, producing an opened N-doped carbon in this molten salt medium can provide a promising approach for synthesizing heteroatom doped carbons with electrochemical performance. [ABSTRACT FROM AUTHOR]

The article starts from an interpretation of the famous review of James Joyce's Ulysses by Carl Gustav Jung called "Ulysses: A Monologue". It focuses mainly on the comparison of the semiological assumptions of the two authors. Although both are aware of the principle of openness and fluidity of the text, it is evident, that their hypotheses, submitted to justify this view, do not have the same efficiency. The article can be also read as an attempt to articulate the so called „serial method", i. e. the Deleuzian critique of the concept of representation from the Logic of Sense. From this point of view, the article could be considered a contribution to the poststructuralist discussion of the concept of sense. [ABSTRACT FROM AUTHOR]

The accurate detection of high-frequency transient fault currents in overhead transmission lines is the basis of malfunction detection and diagnosis. This paper proposes a novel differential winding printed circuit board (PCB) Rogowski coil for the detection of transient fault currents in overhead transmission lines. The interference mechanism of the sensor surrounding the overhead transmission line is analyzed and the guideline for the interference elimination is obtained, and then a differential winding printed circuit board (PCB) Rogowski coil is proposed, where the branch and return line of the PCB coil were designed to be strictly symmetrical by using a joining structure of two semi-rings and collinear twisted pair differential windings in each semi-ring. A serial test is conducted, including the frequency response, linearity, and anti-interference performance as well as a comparison with commercial sensors. Results show that a PCB Rogowski coil has good linearity and resistance to various external magnetic field interferences, thus enabling it to be widely applied in fault-current-collecting devices. [ABSTRACT FROM AUTHOR]

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Background HIV-1 is decorated with trimeric glycoprotein spikes that enable infection by engaging CD4 and a chemokine coreceptor, either CCR5 or CXCR4. The variable loop 3 (V3) of the HIV-1 envelope protein (Env) is the main determinant for coreceptor usage. The predominant CCR5 using (R5) HIV-1 Env has been intensively studied in function and structure, whereas the trimeric architecture of the less frequent, but more cytopathic CXCR4 using (X4) HIV-1 Env is largely unknown, as are the consequences of sequence changes in and near V3 on antigenicity and trimeric Env structure. Results Soluble trimeric gp140 Env constructs were used as immunogenic mimics of the native spikes to analyze their antigenic properties in the context of their overall 3D structure. We generated soluble, uncleaved, gp140 trimers from a prototypic T-cell line-adapted (TCLA) X4 HIV-1 strain (NL4-3) and a hybrid (NL4-3/ADA), in which the V3 spanning region was substituted with that from the primary R5 isolate ADA. Compared to an ADA (R5) gp140, the NL4-3 (X4) construct revealed an overall higher antibody accessibility, which was most pronounced for the CD4 binding site ( CD4bs), but also observed for mAbs against CD4 induced (CD4i) epitopes and gp41 mAbs. V3 mAbs showed significant binding differences to the three constructs, which were refined by SPR analysis. Of interest, the NL4-3/ADA construct with the hybrid NL4-3/ADA CD4bs showed impaired CD4 and CD4bs mAb reactivity despite the presence of the essential elements of the CD4bs epitope. We obtained 3D reconstructions of the NL4-3 and the NL4-3/ADA gp140 trimers via electron microscopy and single particle analysis, which indicates that both constructs inherit a propeller-like architecture. The first 3D reconstruction of an Env construct from an X4 TCLA HIV-1 strain reveals an open conformation, in contrast to recently published more closed structures from R5 Env. Exchanging the X4 V3 spanning region for that of R5 ADA did not alter the open Env architecture as deduced from its very similar 3D reconstruction. Conclusions 3D EM analysis showed an apparent open trimer configuration of X4 NL4-3 gp140 that is not modified by exchanging the V3 spanning region for R5 ADA. [ABSTRACT FROM AUTHOR]