Exchange Behavior Research Articles

Effects of the Ion Exchange and Adsorption Behavior of Clinoptilolite on Chloride Solidification in Cement Paste

Effects of the Ion Exchange and Adsorption Behavior of Clinoptilolite on Chloride Solidification in Cement Paste

An electrospray-active N-heterocyclic carbene ligand for real-time analysis of organometallic reactions.

A charge-tagged N-heterocyclic carbene (NHC) has been synthesized and its utility in allowing the dynamic behaviour of metal complexes to be monitored in real time using electrospray ionization mass spectrometry demonstrated. This compound was used to prepare different metal-NHC complexes, and the kinetic behaviour of complex formation and ligand exchange was monitored in real time through the use of pressurized sample infusion electrospray mass spectrometry (PSI-ESI-MS).

Three-component soliton states in spinor F = 1 Bose–Einstein condensates with PT-symmetric generalized Scarf-II potentials

Abstract Introducing PT-symmetric generalized Scarf-II potentials into the three-coupled nonlinear Gross-Pitaevskii equations offers a new way to seeking stable soliton states in quasi-one-dimensional spin-1 Bose-Einstein condensates. In scenarios where the spin-independent parameter c_0 and the spin-dependent parameter c_2 vary, we use both analytical and numerical methods to investigate the three-coupled nonlinear Gross-Pitaevskii equations with PT-symmetric generalized Scarf-II potentials. We obtain analytical soliton states and find that simply modulating c_2 may change the analytical soliton states from unstable to stable. Additionally, we obtain numerically stable double-hump soliton states propagating in the form of periodic oscillations, exhibiting distinct behavior in energy exchange. For further investigation, we discuss the interaction of numerical double-hump solitons with Gaussian solitons and observe the transfer of energy among the three components. These findings may contribute to a deeper understanding of solitons in Bose-Einstein condensates with PT-symmetric potentials and may hold significance for both theoretical understanding and experimental design in related physics experiments.

Enhanced prediction of Cs removal by CST from Hanford tank waste with K accountability

AbstractThe treatment of Hanford tank waste is one of the most challenging environmental cleanup activities to date. To expedite the processing of liquid waste stored in underground tanks in Washington State it is necessary to remove the significant dose contributor, 137Cs. Crystalline silicotitanate ion exchanger is currently used to remove 137Cs from the aqueous phase of Hanford tank wastes in preparation for vitrification at the Waste Treatment and Immobilization Plant (WTP). Improving the understanding of potassium impacts on ion exchange behavior of Cs will help in the operation of a critical component of one of the most complex treatment processes in the world today. Optimization of this process can result in significant cost savings and less waste production. Toward this effort, a series of batch contact tests varied in potassium concentration were conducted to look at the impact of potassium concentration on Cs distribution. Experimental distribution ratios (Kd) were compared to the distribution ratios predicted using the ZAM model. A significant underprediction of Cs capacity in the presence of potassium was seen with the existing model. A revision of the equilibrium constants was determined and provided a statistically better fit for determining the Cs Kd values in tank waste matrices.

Dissociative Oxygen Adsorption and Incorporation in Co3O4-Dispersed BaZr0.9Sc0.1O2.95 for a PCFC Cathode

Proton-conducting fuel cells (PCFCs), which operate at lower temperatures than conventional solid oxide fuel cells (SOFCs) using an oxide-ion conductor, have attracted considerable attention owing to their high energy-conversion efficiency. Even with mobile protons, oxygen reduction reactions at the cathode limit the performance of PCFCs. To improve their cathode properties, a variety of functional oxides, including the so-called triple conductors, which have mobile oxide ions, protons, and holes, have been developed. Our group has focused on the excellent catalytic activity of Co3O4 for the dissociative adsorption of oxygen at elevated temperatures, which is comparable to that of Co-containing mixed conductors with a perovskite-type structure [1,2]. In this study, Co3O4-dispersed proton-conducting oxides, BaZr0.9Sc0.1O2.95, were prepared for use as composite-type cathodes, and their surface oxygen exchange behavior was investigated using the pulse isotopic exchange (PIE) technique.BaZr0.9Sc0.1O2.95 (BZS10) was prepared using a solid-state reaction method by sintering at 1300 °C for 10 h. To prepare the composite powders, BZS10 powders were ball-milled with x vol%Co3O4 (x = 1, 3, 5, 10, and 50). Prior to PIE, their specific surface area was determined by a BET method for the sample powder heat-treated at 880 °C, which is slightly higher than the highest PIE temperature to avoid morphological and compositional change during PIE. The PIE was performed at 800–200 °C under a 10%O2 atmosphere.Based on the almost constant lattice constants, regardless of the Co3O4 volume fractions, the composites were successfully prepared as a dual-phase state, unlike Co-doped BZS10 prepared at 1225 °C, which showed a decrease in the lattice constant [3]. At 500 °C, the surface oxygen exchange rate R0 of BZS10 without Co3O4 particles was 4.0×10-6 mol/m2·s. R0 was surprisingly enhanced by an order of magnitude with the addition of only 1 vol%Co3O4. Further addition of Co3O4 exceeding 10 vol% reduced R0 . This trend indicates that the optimum amount of Co3O4 provided sufficient dissociated oxygen on BZS10, which was readily incorporated into BZS10. Their electrochemical properties and detailed microstructural analyses are also discussed.[1] Y. Tomura et al., J. Mater. Chem. A, 8 (2022) 21634–21641.[2] A. Ishii et al., ACS Appl. Mater. Interfaces, 15 (2023) 34809−34817.[3] H. Uehara et al., Int. J. Hydrogen Energy, 47 (2022) 5577−5584.

Enhancement of Heat Transfer rate using Axially Interrupted Rectangular Fins in Double Pipe Heat Exchanger

The current investigates the thermo-fluid behavior of a double pipe heat exchanger (DPHE) featuring axially interrupted rectangular fins (AIRF) on the annulus part. The inner tube under this study with AIRF represents an interruption of straight longitudinal fins. This modification introduces periodic breaks along the tube's surface, effectively disrupting the boundary layer of the fluid flow. Consequently, it enables a non-continuous fluid passage along the length of the tube, potentially enhancing heat transfer. The experimentation employs standard liquid water, for investigations conducted under varying cold water mass flow rate 0.136 Kg/s to with 0.374 Kg/s keeping hot water at constant flow rate of 0.34 Kg/s with a fin split interval of four different lengths 7mm,27mm,55mm,100mm. A comprehensive investigation of the AIRF arrangements is carried out in contrast to the plain pipe arrangement, concentrating on fluid flow parameters such as Nusselt number (Nu), friction factor, heat transfer rate, and overall performance factor. The findings reveal that heat transfer rates in an annulus equipped with 7mm AIRF exceed those of a plain pipe by 59.31% under similar fluid flow conditions. The Nusselt number shows 1.5 times increase in the 0.007 m AIRF arrangement compared to the plain pipe. Thermal performance factor for 7mm interrupted length of AIRF outperforms other models.

Enhancing Workplace Well-being: Unveiling the Dynamics of Leader–Member Exchange and Worker Safety Behavior Through Psychological Safety and Job Satisfaction

BackgroundIn healthcare, ensuring safety is crucial for quality care and patient outcomes. While research links leader–member exchange (LMX) quality to safety behavior, this remains understudied in healthcare. Our study explores LMX's long-term impact on safety behavior, proposing a model that includes the moderated mediating role of psychological safety and job satisfaction in the relationship between LMX and safety behaviors, regarding compliance (SCB) and participation (SPB). By identifying the mechanisms through which LMX influences safety behavior, this study can provide insights into the development of interventions that promote workplace safety and enhance the well-being of healthcare workers. MethodsWe collected data from 325 Algerian healthcare workers across three public hospitals at three points. Through SmartPLS analysis, we used advanced features of Partial Least Squares Structural Equation Modeling (PLS-SEM) alongside PROCESS analysis to evaluate the relationships within our proposed model. ResultsOur analysis found a significant association between higher LMX and increased job satisfaction that positively correlated with enhanced SCB adherence and mediated the LMX–SCB relationship. This relationship was strengthened with high psychological safety. ConclusionOur study emphasizes the crucial role of LMX quality in shaping safety behavior among Algerian healthcare workers, providing insights for cultivating a safety culture in healthcare settings, highlighting the significance of prioritizing LMX, JS, and PS to improve workplace safety and support healthcare worker well-being.

Prediction of Heat Transfer in a Hybrid Solar–Thermal–Photovoltaic Heat Exchanger Using Computational Fluid Dynamics

Solar energy is one of the main renewable energy resources due to its abundance. It can be used for two purposes, thermal or photovoltaic applications. However, when the resource obtained is mixed, it is called photovoltaic thermal hybrid, where the solar panels generate electricity and are provided with a heat exchanger to absorb energy through a water flow. This is one of the techniques used by the scientific community to reduce the excess temperature generated by solar radiation in the cells, improving the electrical efficiency of photovoltaic systems and obtaining fluid with higher temperature. In this work, the thermal behavior of a heat exchanger equipped with fins in its interior to increase the thermal efficiency of the system was analyzed using CFD (Computational Fluid Dynamics). The results showed that the average fluid outlet temperature was 75.31 °C, considering an incident irradiance of 1067 W/m2 and a fluid inlet temperature of 27 °C. The operating conditions were obtained from published experimental studies, achieving 97.7% similarity between the two. This was due to the boundary conditions of the heat flux (1067 W/m2) impinging directly on the coupled cells and the heat exchanger in a working area of 0.22 m2.

Robust Self-Healing Adhesives Based on Dynamic Urethane Exchange Reactions.

Thermoset polyurethanes (PUs) have been successfully reprocessed as covalent adaptable networks (CANs) by catalyzing carbamate exchange. Here we extend bond exchange beyond the internal network cross-links to create a dynamic urethane adhesive. Interfacing PU CANs to substrates with nucleophilic functional groups creates adhesives capable of reversible transcarbamoylation with the substrate, which has not been demonstrated previously by CAN adhesives. Two types of thermoset PU films were synthesized, one containing the green carbamate exchange catalyst Zr(tmhd)4 and the other containing no catalyst. Although otherwise identical in chemical and network properties, as indicated by FT-IR spectroscopy and dynamic mechanical thermal analysis (DMTA), the film containing catalyst showed dynamic bond exchange behavior through stress relaxation analysis. When evaluated as an adhesive, the CAN film exhibited self-healing properties and retained its adhesive strength for five cycles, which is attributed to reversible covalent bonding to the glass substrate. This work expands industrially relevant CANs to structural adhesives and demonstrates their potential value in an application that presently employs PUs as single-use materials.

Novel energy exchange behaviors and mechanisms in nonlinear acoustic metamaterials with multiple nonlinear resonators

Wave-wave interactions in a nonlinear metamaterial or structure with two propagating waves can induce energy exchange within the nonlinear systems. The effects of nonlinear resonators on these interactions and energy exchanges in a nonlinear acoustic metamaterial have not been extensively studied in the literature. In this paper, a nonlinear monatomic acoustic metamaterial with multiple nonlinear resonators (NMAM-MNR) is constructed to investigate the new behaviors and mechanisms introduced by these nonlinear resonators. Stability analyses reveal that stability can be tuned by adjusting the number of nonlinear resonators and by selecting different intensities or masses of the resonators and the chain. Additionally, direct numerical simulations are performed to study the novel energy exchange behaviors and mechanisms in NMAM-MNR systems. The results demonstrate that the degree and frequency of energy exchange can be tuned by altering the mass ratios, stiffness ratios, intensities, and natural frequencies of the nonlinear resonators and the chain. The influence of mass and stiffness ratios on the time taken for the B-wave magnitude to first reach its maximum value in NMAM-MNR systems is also studied, showing that the rate of energy exchange induced by wave-wave interactions can be tuned by changing the stiffness and mass ratios of multiple nonlinear resonators. These properties have potential applications in the fields of energy harvesters, waveguides, and resonant energy transfer mechanisms.

Recovery of rare earth elements from ion-adsorption deposits using electro kinetic technology: A comparative study on leaching agents

Ion-adsorption rare earth deposits are crucial sources of heavy rare earth elements. Conventional ammonium-salt leaching techniques have resulted in severe environmental impacts. Electrokinetic mining technology has emerged as a potential solution that can enhance recovery efficiency. However, persistent issues associated with ammonium salts and the influence of electric fields on rare earth elements extraction from ion-adsorption rare earth deposits with alternative leaching agents remain unexplored. In addition, the electrokinetic behavior and mechanisms of rare earth ions and various ions in weathering crusts in an electric field have not been studied. Thus, we report a comparative study of rare earth elements recovery using electrokinetic mining technology with three leaching agents. The results demonstrate that the electrokinetic mining efficiency is enhanced by using magnesium sulfate and ammonium sulfate; however, hindered by sodium sulfate. These differences arise from the diversities in adsorption amounts, and transport characteristics of the leaching cations in soil. Surprisingly, electrokinetic mining technology exhibits superior mining efficiency in high-density soils, contrasting with conventional leaching techniques. Our findings indicate that electromigration, electroosmosis, and electrolysis mechanisms collectively influence the mining process. Remarkably, electrokinetic mining technology achieves a significant rare earth element recovery efficiency of 90 % using magnesium sulfate synergically promoted by the voltage and leaching agent concentration. The findings of this study are expected to provide valuable insights into rare earth elements transport and exchange behavior in an electric field with various leaching agents, thereby contributing to the advancement of sustainable rare earth elements mining practices.

Sorption, kinetic and separation studies of transition and heavy metal ions using cerium amino tris-(methylene phosphonic acid)

ABSTRACT In the present study, the ion exchange behaviour of cerium (IV) amino tris-(methylenephosphonic acid) (CeATMP) towards transition and heavy metal ions has been studied by determining the values of distribution coefficient (Kd) and breakthrough capacity (BTC). Various kinetic models such as pseudo-first-order, pseudo-second-order, and intra-particle diffusion have been applied to determine ion exchange efficiency and compared with the reported works. As a result, CeATMP was found to be an efficient ion exchange material in term of a very short equilibrium time to for a metal ion to occupy an exchange site. Among the separation studies, elution behaviour of these metal ions has been executed using various acids and electrolytes media. A few binary and ternary metal ion separations also have been performed with consideration of Kd values. A study on regeneration shows that material can be reused without loss of the performance ability in term of cation exchange capacity. The present work reveals a significant use of CeATMP as an effective cation exchange material for removing and separation of inorganic contamination as environmental cleaning applications.

Influence of CO2 injection rate and memory water on depressurization-assisted replacement in natural gas hydrates and the implications for effective CO2 sequestration and CH4 exploitation

This study was conducted to investigate the influence of CO2 injection rate and memory water on guest exchange and hydrate reformation behavior in CH4 hydrate-bearing sediment, using a one-dimensional (1-D) reactor to optimize depressurization-assisted replacement. Increasing the CO2 injection rate facilitated the rapid sweeping of CH4 into the pore space of the hydrate-bearing sediment, inducing immediate hydrate reformation and preventing CH4 re-enclathration in the middle region of the 1-D reactor. Despite dissociating 50 % of the initial CH4 hydrate for depressurization-assisted replacement, the replacement efficiency converged at around 70 % due to drastically reformed gas hydrates hindering mass transfer. Introducing time intervals between depressurization and replacement to reduce the residual memory effect of water led to delayed hydrate reformation, altering the longitudinal distribution of replacement efficiency in the 1-D reactor. An increase in replacement efficiency toward the outlet was seen, suggesting that improved CO2 propagation in the hydrate-bearing sediment resulted in a higher CO2 concentration in the vapor phase at the point of hydrate reformation, in turn enhancing CO2 storage efficiency in the newly formed hydrates. These experimental results highlight the importance of CO2 injection rates and time intervals in determining the hydrate reformation behaviors of hydrate-bearing sediments and optimizing the efficiency of depressurization-assisted replacement.

Economic Assessment of Hybrid and Non-Hybrid Maize Crop in Sahiwal Division Under Changing Climate

It is a fine admissible verity all over the world that the changing climate exerts influence on all the kinds of survivals. As an agricultural based economy Pakistan rely on well-being of agriculture and it makes huge contribution in the gross domestic product (GDP) of Pakistan. Agriculture totally nature based and it is straight exaggerated by the exchange behavior of different climatic variables i.e. humidity, rainfall as well as temperature. Minor alter in one of these variables can cause extreme alter in the production of crops and the country’s economy damaged in the result of yield loss. This study will be focused on climate changing impact on hybrid as well as non- hybrid maize crop within Sahiwal division, in the province of Punjab, Pakistan. Sahiwal division is the well-known agricultural production location and on the other side, it is very sensitive to climate change. That is the reason behind the study of the economic assessment of hybrid and non-hybrid maize crop under the climate change in Sahiwal division. With the help of arranged set of questions, check the impact of crop production on net farm revenue and Ricardian analysis operated to quantify the supposed impact due to changing climate. After estimating net farm revenue, it is a regressed against climate, soil and socio-economic variables. Study helps out in assessing the climate changing impact on hybrid as well as non-hybrid maize crop and plus suggesting adoption practices to farmers and thus giving reasonable policy support in the end.

Correlation between Na-Cs Ion Exchange Properties in the Alkaline Form and Acid Strength in the Proton Form of Zeolite.

The ion exchange function of zeolite is useful for such a purpose as the removal of radioactive Cs species from water. In the very early days of zeolite science, the affinity of zeolites for metal cations was explained based on geometry. After the explanation presented above was proposed, many new zeolites and related materials were discovered or synthesized. Furthermore, it has become clear that the chemical nature of the ion exchange sites is strongly dependent on the framework topology. In this study, the ion exchange behavior between Na-form zeolites with different framework topologies and Cs-containing aqueous solutions was analyzed, and the equilibrium constant was calculated based on the Langmuir type equation to investigate the influence of the chemical nature of the zeolite framework on ion selectivity. The equilibrium constants at room temperature were in the order FAU < LTA < MFI < YFI < MOR. This order is the same as the order of Bro̷nsted acid strengths in the corresponding proton form zeolites. It is suggested that the delocalization of charge around the ion exchange site stabilizes a large cation whose charge is delocalized. In contrast, the equilibrium constant was not related to the pore and cavity size. This opens new insight into the influence of the chemical nature of zeolite on the affinity to cation.

Simulation of the Effect of Soil Temperature on Earth - Air Heat Exchanger Behavior

Simulation of the Effect of Soil Temperature on Earth - Air Heat Exchanger Behavior

Strengthening Person Organization Fit and Innovative Work Behavior Through Psychological Capital and Leader-Member Exchange

This study investigates the interrelationships among Psychological Capital, Leader-Member Exchange (LMX), Person-Organization Fit (POF), and Innovative Work Behavior (IWB) within the context of the construction industry in Makassar. The research aims to determine the direct and indirect effects of Psychological Capital and LMX on POF and, subsequently, on IWB among employees. Specifically, the study poses the following research questions: (1) Does Psychological Capital influence Person-Organization Fit among construction company employees? (2) What is the impact of Leader-Member Exchange on Person-Organization Fit in this setting? (3) How do Psychological Capital and Leader-Member Exchange directly affect Innovative Work Behavior? (4) Do Psychological Capital and Leader-Member Exchange indirectly influence Innovative Work Behavior through Person-Organization Fit? The significance of this research lies in its potential to enhance understanding of key human resource constructs and their interplay, which could inform the development of HR management practices. Moreover, the findings are expected to provide actionable insights for construction companies aiming to foster a culture of innovation among their workforce. The methodology encompasses the collection of primary data from 397 employees across various construction companies, employing proportional stratified random sampling to select 199 respondents based on the Slovin Formula with a 5% precision level. Path analysis is conducted using the AMOS 24 software to analyze the data. The anticipated outcomes of this research include the establishment of significant relationships between Psychological Capital and both Person-Organization Fit and Innovative Work Behavior, as well as between Leader-Member Exchange and Person-Organization Fit. Furthermore, the study seeks to explore whether Psychological Capital and Leader-Member Exchange can enhance Innovative Work Behavior mediated by Person-Organization Fit. The results aim to contribute both theoretically to academic discourse and practically as a resource for organizational development in the construction sector.

Influence of MgAl–NO2-LDHs on passivation of reinforcing steel in simulated geopolymer solution

Because of ion exchange properties, the presence of layered double hydroxides (LDHs) influences passivation process of reinforcement embedded in geopolymer concrete. In this study, the ion exchange behavior of MgAl–NO2-LDHs and its effect on the characteristics of passivation film and electrochemical behavior of passive reinforcement in simulated slag-fly ash-waste ceramic powders geopolymer solution (SGP) are extensively investigated. The results indicate that LDHs with layered structure improve the protection efficiency of adsorption layer in SGP. Further, the intercalated NO2− is efficiently exchanged with OH− in SGP, thus increasing the thickness and corrosion resistance of the formed passivation film. However, because the adsorption layer halts NO2− release process, the beneficial effect is mainly observed during later immersion stage.

Ricardo’s Law of Comparative Advantage in Bronze Age, Iron Age, and Early Historic Mainland Southeast Asian Metallurgy: Copper-base Metal Production, Exchange, and Consumption Behaviours at Khao Sai On, Nil Kham Haeng, Non Pa Wai, Phromthin Tai, Sab Champa, and Tha Kae in Central Thailand

Since its late 1970s to early 1980s discovery, the Khao Wong Prachan Valley (KWPV) of central Thailand has been assumed to have been a major supplier of copper in Bronze Age, Iron Age, and Early Historic Southeast Asia. KWPV was the first regional metal production system to be characterised by lead isotope (LI) analysis in the late 2000s, revealing a coherent signature easily distinguished from subsequent analyses of production systems at Phu Lon (northern Thailand) and the Vilabouly Complex (central Laos). Despite KWPV’s scale of production, its LI signature has scarcely been detected at Bronze Age metal consumption sites in nearby northeast Thailand and not at all in Iron Age assemblages. We study copper production and copper/bronze consumption behaviours of Iron Age and Early Historic sites in KWPV’s immediate vicinity: Khao Sai On, Phromthin Tai, Tha Kae, and Sab Champa. Khao Sai On and Phromthin Tai production signatures are highly consistent with those previously established, while the uranogenic tendency at Tha Kae explains outliers from Bronze Age Non Pa Wai and Nil Kham Haeng. Analysis of consumption assemblages reveals little to no consistency with local production signatures. This tendency was tested with LI Iron Age and Early Historic datasets for Ban Khu Muang, Ban Mai Chaimongkol, Ban Pong Manao, and Ban Pong Takhob. The pattern is clear: central Thai populations imported copper/bronze, potentially from the Vilabouly Complex or production loci with closely comparable signatures. We examine this counterintuitive behaviour inductively using Ricardo’s Law of Comparative Advantage combined with a technological appreciation of the relatively low productivity of central Thai primary copper production. This suggests central Thailand’s unattached copper producers freely exchanged copper for exotic goods (bronze, glass, semi-precious stone), with potentially poor terms of exchange, from their desire to participate in wider regional trends in conspicuous consumption.

Knowledge Sharing Behaviour is Critical for Business Continuity in A Pandemic

The widespread COVID-19 epidemic has had a profound impact on businesses all around the world by hastening their digitalization. The operations of the airport are also being transformed to ensure business continuity. The Malaysian government's mobility control order (MCO) requires workers to work from home on alternate days. This working structure necessitated requirements for active knowledge exchange behavior. This study examines Airport Terminal Services (ATS) employees' knowledge sharing attitudes, subjective standards, and perceived control behaviors using quantitative method. The findings show that the associations between attitude and perceived control behavior in knowledge sharing are moderate. The respondents demonstrate weak relationships between subjective norms and knowledge sharing. As a result, it is suggested that ATS should invest in improving the subjective norm by developing a knowledge sharing culture within the firm. A comprehensive knowledge management system that includes data and information access, storage, and retrieval would allow the corporation to continue operations regardless of the situation. Knowledge sharing is accelerated via constant communication, staff engagement, and training. Airport operations are vulnerable to a variety of unforeseen events, including pandemics, natural disasters, and accidents. As a result, ensuring a resilient design of work processes and workers' desire to embark on the change endeavor is critical to corporate sustainability.