Ideal Behavior Research Articles

KCl-UCl3 molten salts investigated by Ab Initio Molecular Dynamics (AIMD) simulations: A comparative study with three dispersion models

Ab Initio Molecular Dynamics (AIMD) simulations are performed on molten KCl-UCl3 salt mixtures to determine energies, heat capacities, and densities. The density-dependent energy correction (DFT-dDsC), Grimme et al.'s DFT-D3, and Langreth & Lundqvist (vdW-cx) models are used for dispersion forces and combined with the Perdew-Burke-Ernzerhof (PBE) exchange-correlation potential with a Hubbard U parameter for the 5f electrons of uranium. After validating predictions for the end-member systems to literature data, KCl-UCl3 mixtures are studied at select temperatures. Densities and energies both deviate from ideal solution behavior, with the maximum deviation occurring around 36% UCl3 for mixing energies and slightly lower (29% UCl3) for densities. Compared to the NaCl-UCl3 system, which was previously investigated using the same simulation methodologies, the KCl-UCl3 density and mixing energy deviations from ideal solution behavior are larger by almost a factor of two. No deviation from ideal solution behavior for heat capacity was observed. The AIMD predictions for mixing energies and densities agree qualitatively with experimental data, though the spread in data obtained from the various dispersion force models utilized, measurements, and empirical estimates makes strong conclusions difficult. The dependence of thermodynamic and thermophysical properties on composition is correlated with the local chemistry of the solution phase, in particular, the tendency of UCl3 to form network structures.

Morphology-Controlled Ion Transport in Mixed-Orientation Polymers.

Advancing iontronics with precisely controlled ion transport is fundamentally important to bridge external organic electronics with the biosystem. This long-standing goal, however, is thus far limited by the trade-off between the active ion electromigration and idle diffusion leakage in the (semi)crystalline film. Here, we presented a mixed-orientation strategy by blending a conjugated polymer, allowing for simultaneously high ion electromigration efficiency and low leakage. Our studies revealed that edge-on aggregation with a significant percolative pathway exhibits much higher ion permeability than that of the face-on counterpart but encounters pronounced leakage diffusion. Through carefully engineering the mixed orientations, the polymer composite demonstrated an ideal switchable ion-transport behavior, achieving a remarkably high electromigration efficiency exceeding one quadrillion ions per milliliter per minute and negligible idle leakage. This proof of concept, validated by drug release in a skin-conformable organic electronic ion pump (OEIP), offers a rational approach for the development of multifunctional iontronic devices.

Shallow beds are not plug flow reactors – Analysis of kinetic data in the presence of axial dispersion effects

Laboratory-scale shallow beds filled with catalyst particles are frequently used in catalyst screening, activity tests and kinetic measurements. Often the experimental data are interpreted with plug flow or differential reactor models. Residence time measurements have shown large deviations from ideal plug flow behavior in shallow beds, indication the presence of axial dispersion effects, i.e. is backmixing and diffusion in the bed. The behavior of laboratory-scale bed reactors was investigated by theoretical considerations of the axial dispersion model and numerical simulations in the Damköhler-Péclet space. The results revealed that large errors in kinetic parameters can appear when the dispersion model is replaced by the plug flow model. This key effect was quantified using the ratio (F) of two Damköhler numbers: the real one, and the one wrongly estimated on experimental data affected by dispersion problems and interpreted with ideal plug-flow approach. Thus, the effect of back-mixing is evaluated varying a single parameter of the kinetic model, namely the rate constant. The conclusions are valid for power-law, Langmuir-Hinshelwood and Eley-Rideal kinetics.

Adsorption and sensing behavior of Cr-doped WS2 monolayer for hazardous gases in agricultural greenhouses: A DFT study

This study used Density functional theory (DFT) to analyze the adsorption behavior of the Cr-doped WS2 monolayer on five hazardous gases (NH3, SO2, NO, NO2, and CO) in agricultural greenhouses. The optimal stable doped site for the Cr atom was identified, and various adsorption parameters such as adsorption energy, adsorption distance, charge transfer and desorption time were calculated. Results indicated that intrinsic WS2 had limited adsorption capacity for five target gases. Moreover, Cr doped significantly enhanced WS2 monolayer conductivity, shifting NH3, SO2, NO and NO2 adsorption from physisorption to chemisorption with Eads <0.6 eV, while CO remained physisorbed. The conductivity of the five gases underwent significant changes after adsorption on Cr-WS2. Desorption times at four temperatures (298 K, 398 K, 498 K and 598 K) indicate that Cr-WS2 demonstrates ideal gas sensor behavior for NH3 gas. However, the physisorbed and short desorption at room temperature suggested unsuitability for CO detection in practical applications. Conversely, the extended desorption time at 598 K made Cr-WS2 more appropriate as a gas scavenger for SO2, NO and NO2 gases. These findings underscore the potential of Cr-WS2 monolayers as novel gas warning or adsorbent materials, offering crucial applications in detecting and removing hazardous gases in agricultural greenhouses.

Failure mechanisms in pre-tensioned bonded hybrid joints

ABSTRACT This study investigated the failure mode of pre-tensioned bonded hybrid joints in steel structures using Digital Image Correlation (DIC) alongside Finite Element Analysis (FEA) and compared the results with those of adhesive bonded joints of identical geometry. While all joint types initially exhibited ideal adhesive joint behaviour at low loading levels, with linear elastic response, differences emerged as loading increased. In particular, hybrid joints exhibited out-of-plane deformations near the ends of the splice plates, a feature not observed in bonded joints. Shear deformations consistently peaked at the ends of the overlap for all joint types and increased with increasing load levels. In contrast to bonded joints, hybrid joints demonstrated resilience under escalating loads, maintaining resistance due to the presence of bolts despite the increased deformations. This study contributes to the understanding of the observed failure mode: while hybrid joints initially resembled ideal bonded joints at lower loads, increasing loads caused critical cracks to initiate at the overlap ends in the adhesive layer, culminating in bonded joint failure. In conclusion, this study has elucidated the failure mode of hybrid joints, providing insights for modelling and dimensioning in steel structures.

Measurement of the double-layer capacitance of Pt(111) in acidic conditions near the potential of zero charge

Quantifying the charge density stored at the Pt(111)/aqueous interface using the double-layer capacitance close to the potential of zero charge (Cdl,PZC) at 0.30 VNHE is of critical importance to elucidating the structure of the electrical double layer (EDL) in the absence of any competing adsorption processes. Marked discrepancies in the values of Cdl for this interface exist in the literature, which we show are likely attributable to the measurement technique used. To directly observe the predicted Gouy-Chapman capacitance minimum at the PZC in the double-layer window between 0.40-0.55 VRHE, anomalously low electrolyte concentrations (0.1 mM HClO4) are needed. The measurement of accurate values of Cdl,PZC is made highly non-trivial by the extremely large solution resistances (∼80-100 kΩ) measured in this required dilute electrolyte as well as the non-negligible deviations from ideal capacitive behaviour (i.e., constant phase element behaviour) displayed even by this well-ordered model electrochemical system. We provide here a comparison between using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and alternating current-cyclic voltammetry (AC-CV) in determining Cdl,PZC for the Pt(111)/HClO4 interface, for different concentrations of the electrolyte. In particular, even when using optimized experimental parameters, we show that the estimated values of Cdl,PZC at 0.1 mM HClO4 still display a marked discrepancy depending on the technique used, ranging from 27-41 μF cm−2. At higher HClO4 concentrations, the discrepancies are much less pronounced. Importantly, however, the measured deviation from Gouy-Chapman theory, as quantified by the Parsons-Zobel plot slope, remains consistent across these techniques, implying that the EDL structure of the Pt(111)/aqueous interface continues to prove anomalous and enigmatic.

Toward Ideal Low-Frequency Noise in Monolayer CVD MoS2 FETs: Influence of van der Waals Junctions and Sulfur Vacancy Management.

The pursuit of sub-1-nm field-effect transistor (FET) channels within 3D semiconducting crystals faces challenges due to diminished gate electrostatics and increased charge carrier scattering. 2D semiconductors, exemplified by transition metal dichalcogenides, provide a promising alternative. However, the non-idealities, such as excess low-frequency noise (LFN) in 2D FETs, present substantial hurdles to their realization and commercialization. In this study, ideal LFN characteristics in monolayer MoS2 FETs are attained by engineering the metal-2D semiconductor contact and the subgap density of states (DOS). By probing non-ideal contact resistance effects using CuS and Au electrodes, it is uncovered that excess contact noise in the high drain current (ID) region can be substantially reduced by forming a van der Waals junction with CuS electrodes. Furthermore, thermal annealing effectively mitigates sulfur vacancy-induced subgap density of states (DOS), diminishing excess noise in the low ID region. Through meticulous optimization of metal-2D semiconductor contacts and subgap DOS, alignment of 1/f noise with the pure carrier number fluctuation model is achieved, ultimately achieving the sought-after ideal LFN behavior in monolayer MoS2 FETs. This study underscores the necessity of refining excess noise, heralding improved performance and reliability of 2D electronic devices.

Preferred Behavior Change Techniques for Physical Activity Interventions among Persons Newly Diagnosed with Multiple Sclerosis: A Qualitative Study

There is increasing interest by researchers and clinicians in behavior change interventions for promoting physical activity in persons newly diagnosed with MS. Ideally, such interventions require the delivery of behavior change techniques (BCTs) based on theory and the selection of BCTs might further require tailoring for this MS subpopulation. The current study examined BCTs preferred by persons newly diagnosed with MS for informing the design and delivery of physical activity behavior change interventions in early-stages of MS. We recruited and interviewed 20 persons newly diagnosed with MS (i.e., disease duration ≤ 2 years). The interviews were conducted online via video conferencing platform and followed a semi-structured script. During the interviews, participants provided opinions regarding an ideal physical activity behavior change program, and the opinions of participants were mapped with the Intervention Functions of the Behavior Change Wheel, BCTs, and BCT groups. Ten frequently mentioned BCTs were identified as preferred strategies for a physical activity behavior change intervention among persons newly diagnosed with MS. These BCTs focused on providing social support, skills and strategies for physical activity performance and regulation, and knowledge on benefits of physical activity in MS. This research provides a refined list of BCTs that can be included when designing tailored physical activity behavior change interventions for persons newly diagnosed with MS.

Microwave irradiation-induced yield enhancement of coconut shell biomass-derived graphene-like material

This paper reports a new strategy (rapid and selective microwave irradiation) to achieve an improved yield of graphene-like material derived from coconut shell biomass. The influence of various microwave irradiation (MWI) powers (80, 240, and 400 W) treatment on the crystalline structures, morphology, and electrochemical performance of the produced samples was determined and compared with the virgin-untreated specimen. The obtained samples were analyzed using varied analytical techniques. The FESEM images of the irradiated samples revealed the existence of graphene-like morphologies accompanied by some thin and transparent sheets. The sample at 80 W displayed the best quality with the highest yield, improving the carbon content, reducing the oxygen functional groups, and increasing the BET-specific surface area by as much as 1238.48 m2/g. The electrochemical properties of the sample treated at 80 W (optimum MWI power treatment) exhibited rectangular curves against scanning speeds, indicating an ideal capacitive behaviour called electric double-layer capacitance (EDLC). It is asserted that the proposed systematic and eco-friendly approach in obtaining the high-performance graphene-like material at low cost may open up sundry opportunities for practical applications, leading towards sustainable development.

Effect of doping and preparation parameter on AC conductivity and dielectric modulus formalism of Al doped DLC thin films

Here, we report the composite effect of aluminum doping on the dielectric response of Diamond-Like Carbon (DLC) thin films. In addition, the contribution from preparation parameters like acetylene flow rate is also considered to understand sample behavior. AC conductivity study shows the existence of a nonlinear increase of conductivity with frequency leading toward the Jump Relaxation Model (JRM). The transition frequency (ft) is observed, which increases with conductivity. The study reveals that dielectric response is influenced by space charge conductivity, prompting us to adopt the modified Debye law. Deviation from ideal Debye behavior is also confirmed in dielectric modulus analysis. The deviation is frequency-dependent, and a higher deviation is observed in the high-frequency region. Plotting of the Master curve shows the presence of different relaxation dynamics in different samples. A current-voltage (I-V) study of different samples is also undertaken, showing higher values (greater than unity) of the ideality factor.

Spectral Analysis of Proton Eigenfunctions in Crystalline Environments

The Schrödinger equation and Bloch theorem are applied to examine a system of protons confined within a periodic potential, accounting for deviations from ideal harmonic behavior due to real-world conditions like truncated and non-quadratic potentials, in both one-dimensional and three-dimensional scenarios. Numerical computation of the energy spectrum of bound eigenfunctions in both cases reveals intriguing structures, including bound states with degeneracy matching the site number Nw, reminiscent of a finite harmonic oscillator spectrum. In contrast to electronic energy bands, the proton system displays a greater number of possible bound states due to the significant mass of protons. Extending previous research, this study rigorously determines the constraints on the energy gap and oscillation amplitude of the previously identified coherent states. The deviations in energy level spacing identified in the computed spectrum, leading to the minor splitting of electromagnetic modes, are analyzed and found not to hinder the onset of coherence. Finally, a more precise value of the energy gap is determined for the proton coherent states, ensuring their stability against thermal decoherence up to the melting temperature of the hosting metal.

Anisotropic exchange interaction of two hole-spin qubits

Semiconductor spin qubits offer the potential to employ industrial transistor technology to produce large-scale quantum computers. Silicon hole spin qubits benefit from fast all-electrical qubit control and sweet spots to counteract charge and nuclear spin noise. However, the demonstration of a two-qubit interaction has remained an open challenge. One missing factor is an understanding of the exchange coupling in the presence of a strong spin–orbit interaction. Here we study two hole-spin qubits in a silicon fin field-effect transistor, the workhorse device of today’s semiconductor industry. We demonstrate electrical tunability of the exchange splitting from above 500 MHz to close-to-off and perform a conditional spin-flip in 24 ns. The exchange is anisotropic because of the spin–orbit interaction. Upon tunnelling from one quantum dot to the other, the spin is rotated by almost 180 degrees. The exchange Hamiltonian no longer has the Heisenberg form and can be engineered such that it enables two-qubit controlled rotation gates without a trade-off between speed and fidelity. This ideal behaviour applies over a wide range of magnetic field orientations, rendering the concept robust with respect to variations from qubit to qubit, indicating that it is a suitable approach for realizing a large-scale quantum computer.

A Study on the Effect of Dilution on Refractive Index of Acetone

This r study investigates the impact of dilution on the refractive index of acetone-water solutions, aiming to study the relationship between solution concentration and optical properties. The experiment involves preparing a series of acetone-water solutions with varying concentrations and measuring their refractive indices using a spectrometer. The abstract will outline the methodology employed, including the preparation of solutions, experimental setup, and data collection procedures. It will also highlight the use of refractive index measurements in describing the characteristics of solutions and their applicability in physics, chemistry, and materials science. The study's expected findings, including the possibility of departures from ideal behaviour and the relationship between solution concentration and refractive index, will be covered in the abstract. It will also stress how crucial it is to understand how dilution affects refractive index for real-world uses, like those in the food, chemical, and pharmaceutical sectors. A greater understanding of solution chemistry and optical phenomena will result from this research's insightful observations of the optical behaviour of acetone-water solutions. Key Words: optics, spectrometer, refractive index, acetone

Cardiovascular Health and Colorectal Cancer Screening in Black Men: A Cross-Sectional Analysis.

African American/Black (henceforth Black) men face disproportionate risks of morbidity and mortality from both cardiovascular disease (CVD) and colorectal cancer (CRC). The American Heart Association's Life's Simple 7 (LS7) tool was designed to examine predictors of CVD with included behaviors also linked to CRC risk (i.e., smoking status, weight, diet, and physical activity). However, no studies have combined LS7 assessment alongside CRC screening history, which serves as a proxy for assessing CRC risk, in Black men. In this study, Black men aged 45-75 participating in annual community wellness events were screened for 6 of 7 LS7 measures (excluding diet, LS6) and self-reported CRC screening. Analyses conducted using R 4.0.5. revealed that Black men (N = 680), with an average age of 57.3 years (SD = 7.5), reported poor (39.7%), intermediate (34.6%), or ideal (25.7%) LS6 scores with higher scores corresponding to lower risk for CVD. However, for every 1-point increase in LS6 scores (0-6), there was a 26% lower odds of reported CRC screening (p = .001). In the fully adjusted model, men with 4+ ideal LS6 behaviors had a 60% lower odds of self-reported CRC screening compared to those with two ideal LS6 behaviors (p < .001). These findings underscore the need for culturally relevant interventions for Black men across all levels of cardiovascular health (CVH) to increase CRC screening uptake.

Synthesis of Niobium Pentoxide and Its Reduced Graphene Oxide Nanocomposite for Enhanced Supercapacitor Applications

Synthesis of Niobium Pentoxide and Its Reduced Graphene Oxide Nanocomposite for Enhanced Supercapacitor Applications

Analysis of the non-ideal crosslinking process in thiol-X “click” thermosets

Thiol-click reactions are widely used in the preparation of thermosets. The network build-up process follows step-wise polymerization behavior, which is commonly analyzed assuming ideal step-wise behavior using well-known expressions such as the Flory-Stockmayer equation for the prediction of the gel point conversion. However, a number of factors contributing to departures from the expected ideal behavior can be identified: a) impurity of the reagents, b) complexity of the reaction mechanism and c) internal cyclization processes. In order to maximize the accuracy of predictions about the expected crosslinking behavior and therefore fine-tune the design of thermosets designed as dual-curing systems or covalent adaptable networks (CANs), it is necessary to take into consideration all these sources of non-ideality. In this work, we aim to describe the effects of such factors on the network build-up process of thiol-click thermosets, making use of the recursive methodology of Miller and Macosko. The contribution of each factor is analyzed separately and their overall combined effect is discussed in relation with real data reported in the literature and experimental results.

On the temperature dependence of the current conduction mode in non-homogeneous Pt/n-GaN Schottky barrier diode

Forward current-voltage (I–V) measurements of Pt/n-GaN Schottky barrier diode (SBD) are investigated in a wide temperature range (80–400 K). The temperature dependence of the effective Schottky barrier height (SBH) and ideality factor are analyzed on the basis of the thermionic emission (TE) model by considering a double Gaussian distribution (DGD) of SBH due to the presence of barrier height inhomogeneities at the Pt/n-GaN interface. In the high temperature (HT) region (200–400 K), Pt/n-GaN SBD exhibits nearly an ideal behavior in accordance with the TE conduction mode. The obtained values of the homogeneous SBH Φ‾0bn = 1.33 eV and Richardson constant AHT* = 26.86 A cm−2 K−2are in agreement with the theoretical values for n-type GaN. In the low temperature (LT) region (80–160 K), the corresponding values Φ‾0bn = 0.94 eV and ALT* = 14.74 A cm−2 K−2 deduced within the TE mode deviate strongly from the ideal behavior. This deviation is further confirmed by the large ideality factor. In this work, we provide a strong evidence that the tunneling current including thermionic field emission (TFE) largely dominates the conduction mode at low temperature.

Communication Ideologies and Social Interface Expertise of Public Elementary School Teachers

This study aimed to determine if communication ideologies significantly influence the social interface expertise of public secondary school teachers in the Division of Panabo, Davao del Norte. It utilized a non-experimental quantitative research design employing the correlational method. The respondents included 130 teachers from public elementary schools, selected through universal sampling. Data analysis involved calculating the mean, Pearson correlation coefficient (r), and regression analysis. The findings revealed that public secondary school teachers often demonstrated high communication ideologies across dimensions such as incomparable, inspirational, consistent, ideal behaviour, good listening, and charismatic traits. Moreover, the teachers frequently manifested the social interface expertise of public secondary school teachers, including skills in edition, goal accomplishment, assimilation, and expectancy. Furthermore, the study found a significant relationship between communication ideologies and social interface expertise among public secondary school teachers. It also indicated that the domains of communication ideologies significantly influenced the social interface expertise of these teachers. The results suggest that teachers should be adept at delivering and comprehending information quickly and accurately. Effective communication is a vital life skill that should not be underestimated. It fosters respect and encourages the willingness to consider different points of view. Facilitating open and constructive exchanges among colleagues can contribute to a more positive working environment.

Edukasi Peningkatan Motivasi Kunjungan Kesehatan Gigi Dan Mulut di Puskesmas Muara Siberut, Kabupaten Kepulauan Mentawai, Provinsi Sumatera Barat

Mentawai ethnic group has unique traditions like anterior teeth mutilation and the use of herbal medicines by sikerei or siaggai laggek (traditional doctor) that cause low visitation to community health centers. The low level of puskesmas utilization rate impacts the failure to achieve the work program of the puskesmas in improving public health status, especially oral health, then influences the quality of health center services (puskesmas). This activity aims to increase community visits and the utilization of health services in Puskesmas Muara Siberut. This activity lasted on July 21, 2023, and was carried out in Muntei Village (work area of the Puskesmas Muara Siberut), South Siberut District, Mentawai Islands Regency, West Sumatra Province. This service uses four methods: observation, planning, action, and evaluation. The results obtained from this activity were an increase in public knowledge regarding ideal behavior in increasing motivation to utilize dental and oral health services at the Muara Siberut Community Health Center through post-test scores at the end of the counseling session. With this service activity, it is hoped that the attitudes and actions of the oral health utilization will increase significantly, along with the high level of public knowledge after being given counseling, so that it will also have an impact in improving the degree of oral health communities

Symmetric physically unclonable functions of the arbiter type

Objectives. The problem of constructing a new class of physically unclonable functions of the arbiter type (APUF) that combines the advantages of both classical and balanced APUF is solved. The relevance of such a study is associated with the active development of physical cryptography. The following goals are pursued in the work: research and analysis of classical APUF, construction of a new mathematical model of APUF and development of a new basic element of APUF.Methods. The methods of synthesis and analysis of digital devices are used, including those based on programmable logic integrated circuits, the basics of Boolean algebra and circuitry.Results. It has been established that classical APUF uses a standard basic element that performs three functions, namely, the function of generating two random variables Generate, the function of choosing a pair of paths Select and the function of switching paths Switch, which are specified by one bit of the challenge. It is shown that the joint use of these functions, on the one hand, makes it possible to achieve high characteristics of the APUF, and on the other hand, leads to the formation of an asymmetric behavior of the APUF. In order to analyze the main characteristics of APUF and their ideal behavior, a new mathematical model of APUF was considered, similar to the model of random coin toss. To implement APUF functioning according to the proposed model, a new basic element was developed. It is shown that the use of the proposed basic element allows to build symmetrical physically unclonable functions (C_APUF), which differ from the classical APUF in that the Generate, Select and Switch functions of the basic element are performed by their independent components and are specified by different bits of challenge.Conclusion. The proposed approach to the construction of symmetrical physically unclonable functions, based on the implementation of the Generate, Select and Switch functions by various components of the base element, has shown its efficiency and promise. The effect of improving the characteristics of similar C_APUF has been experimentally confirmed, and, first of all, a noticeable improvement in their probabilistic properties expressed in equal probability of responses. It seems promising to further develop the ideas of building C_APUF, experimental study of their characteristics, as well as analysis of resistance to various types of attacks, including using machine learning.