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The aim of this paper is to present advanced experimental–numerical methods for identification of spectral absorption and scattering properties of highly porous ceria ceramics in the range of semi-transparency at room and elevated temperatures.

At room temperature, a period of quasi-steady oscillations of the sample surface temperature generated in response to recurrent laser heating at fixed values of the maximum and minimum temperature of the irradiated surface is measured along with the normal-hemispherical reflectance. Radiative properties are then identified using a combined heat transfer model. At elevated temperatures, an analytical solution proposed in an earlier study for zirconia ceramics is used to retrieve spectral absorption coefficient of ceria ceramics from the measured normal emittance.

This method can be used to obtain small absorption coefficient of ceria ceramics at room temperature. The required measurements of both the normal-hemispherical reflectance and the period of quasi-steady oscillations of the irradiated surface temperature of the ceramics sample between fixed values of the maximum and minimum temperatures can be readily conducted using thermal laboratory equipment. Another method has been suggested for identification of the spectral absorption coefficient of ceria ceramics at elevated temperatures. This method is based on a relation between the measured normal emittance of an isothermal sample and the absorption coefficient.

This paper aims to investigate the effect of introducing nano-ceria (CeO₂) particles to the epoxy coatings on mild steel in natural seawater.

The epoxy–ceria nanoparticles were coated with mild steel using a wire-wound draw-down bar method. The effects of ceria nanoparticles on the corrosion resistance of epoxy-coated samples were analyzed using scanning electrochemical microscopy (SECM) and electrochemical impedance spectroscopy (EIS).

Localized measurements such as oxygen consumption and iron dissolution were observed using SECM in natural seawater in the epoxy-coated sample. The increase in film resistance (R_f) and charge transfer resistance (R_ct) values by the addition of nano-ceria particles in the epoxy coating was measured from EIS measurements after wet and dry cyclic corrosion test. Scanning electron microscope (SEM)/energy dispersive X-ray spectroscope (EDX) analysis showed that complex oxides of nano-ceria were enriched in corrosion products at a scratched area of the coated mild steel after corrosion testing. Focused ion beam-transmission electron microscope (FIB-TEM) analysis confirmed the presence of the nanoscale oxide layers of ceria in the rust of the steel.

The tip current at −0.70 V for the epoxy–CeO₂-coated sample decreased rapidly because of cathodic reduction of the dissolved oxygen. The increase in film resistance (R_f) and charge transfer resistance (R_ct) values by the addition of nano-ceria particles in the epoxy coating were measured from EIS measurements after wet and dry cyclic corrosion test.

The presence of complex oxide layers of nano-ceria layers protects the coated steel from rusting.

The use of this nano-ceria for corrosion protection is environment-friendly.

The results of this study indicated the significant effect of nano-ceria particles on the protective performance and corrosion resistance of the epoxy coating on mild steel. The dissolution of Fe²⁺ was lower in the epoxy–ceria nanoparticle-coated mild steel than that of the epoxy-coated mild steel resulting in a lower anodic current of steel. The increase in film resistance and the charge transfer resistance showed that the nano-ceria particles and the formation of complex oxides provide better barrier protection to the coating metal surfaces.

To develop new eco‐environmentally friendly surface treatments based on cerate compounds as alternatives to the process involving toxic chromates for the corrosion protection of magnesium alloys.

A treatment process in which a surface was alkaline‐etched prior to ceria treatment is proposed. The process involves cleaning, etching in potassium hydroxide followed by treatment in ceria conversion coatings. The effect of surface preparation prior to ceria treatment on the corrosion resistance of AZ91D in 3.5 per cent NaCl solution was measured using AC impedance spectroscopy and DC polarization techniques. Surface examination was performed by scanning electron microscopy, energy dispersive X‐ray.

It was shown that the ceria treatment can be used as a localized corrosion inhibitor for alloy AZ91D in NaCl solution. The level of inhibition strongly depended on the cerium concentration. Moreover, ceria treatments improved the pitting corrosion resistance due to the formation of protective oxide films which act as a barrier to oxygen diffusion to the metal surface. According to the EIS and polarization measurements, alkaline etching in KOH is more effective in reducing the pitting corrosion of AZ91D than was HCl. It was shown that surface treatment in alkaline solution (KOH) prior to ceria treatments played an important role in inhibiting the active surface sites, rejecting the chloride ions from the surface and forming uniformly distributed oxide film.

Ceria conversion coatings seem very promising as alternatives to toxic chromating for the corrosion protection of magnesium alloys in NaCl solution.

Criminalization of drug use in Malaysia has concentrated people who inject drugs (PWID) and people living with HIV into prisons where health services are minimal and HIV-related mortality is high. Few studies have comprehensively assessed the complex health needs of this population. The paper aims to discuss these issues.

From October 2012 through March 2013, 221 sequentially selected HIV-infected male prisoners underwent a comprehensive health assessment that included a structured history, physical examination, and clinically indicated diagnostic studies.

Participants were mostly PWID (83.7 percent) and diagnosed with HIV while incarcerated (66.9 percent). Prevalence of hepatitis C virus (90.4 percent), untreated syphilis (8.1 percent), active (13.1 percent), and latent (81.2 percent) tuberculosis infection was several fold higher than non-prisoner Malaysian adults, as was tobacco use (71.9 percent) and heavy drinking (30.8 percent). Most (89.5 percent) were aware of their HIV status before the current incarceration, yet few had been engaged previously in HIV care, including pre-incarceration CD4 monitoring (24.7 percent) or prescribed antiretroviral therapy (ART) (16.7 percent). Despite most (73.7 percent) meeting Malaysia’s criteria for ART (CD4 <350 cells/μL), less than half (48.4 percent) ultimately received it. Nearly one-quarter (22.8 percent) of those with AIDS (<200 cells/μL) did not receive ART.

Drug addiction and communicable disease comorbidity, which interact negatively and synergistically with HIV and pose serious public health threats, are highly prevalent in HIV-infected prisoners. Interventions to address the critical shortage of healthcare providers and large gaps in treatment for HIV and other co-morbid conditions are urgently needed to meet the health needs of HIV-infected Malaysian prisoners, most of whom will soon transition to the community.

The purpose of this article is twofold. First, this study characterises the current state of the bio-packaging market's development. Second, it identifies key factors influencing and possible scenarios of the bio-packaging market transition to increase the market share of compostable packaging.

The results of 29 in-depth interviews (IDIs) with representatives of the key groups of bio-packaging supply chains' (SCs') stakeholders were the input for the consideration of the research problem.

The main economic, legal, social and technological enablers and barriers to the bio-packaging regime transition are recognised, and their impact at the market level is explained. The authors recognised the hybrid transition scenario towards an increase in the market share of compostable packaging related to the three traditional pathways of transformation, reconfiguration and technological substitution.

This study contributes to a better understanding of the socio-technical system theory by examining interdependencies between landscape (external environment), market regime (bio-packaging market) and niche innovations (compostable packaging) as well as system transition pathways. The findings and conclusions on bio-packaging market developments can be important lessons learnt to be applied in different countries due to the same current development stage of the compostable packaging lifecycle worldwide.

The purpose of this work is to present the strategies and current state of development in the field of micro solid oxide fuel cells (μSOFC).

In the paper recent strategies of conventional and single chamber μSOFC are described. Some examples based on the author's research are presented.

It can be concluded that scale down of ceramic technologies is still more popular than MEMS. However, MEMS‐based technologies become recently to be used more frequently.

The work is limited to the description of materials and technologies used in μSOFC.

The review presents very recent research in μSOFC. The results demonstrate critical areas in development of suitable technologies.

The purpose of this study is to develop a simulation method to calculate non-stationary distributions of the chemical potential of oxygen in a solid oxide fuel cell (SOFC) under operation.

The initial-boundary value problem was appropriately formulated and the appropriate boundary conditions were implemented so that the problem of non-stationary behavior of SOFC can be solved in accordance with actual operational and typical experimental conditions. The dependencies of the material properties on the temperature and partial pressure of oxygen were also elaborately introduced to realize actual material responses. The capability of the proposed simulation method was demonstrated under arbitrary operating conditions.

The steady state calculated with the open circuit voltage condition was conformable with the analytical solution. In addition, the transient states of the spatial distributions of potentials and currents under the voltage- and current-controlled conditions were successfully differentiated, even though they eventually became the same steady state. Furthermore, the effects of dense materials assumed for interconnects and current collectors were found to not be influential. It is thus safe to conclude that the proposed method enables us to simulate any type of transient simulations regardless of controlling conditions.

Although only uniaxial models were tested in the numerical examples in this paper, the proposed method is applicable for arbitrary shapes of SOFC cells.

The value of this paper is that adequate numerical simulations by the proposed method properly captured the electrochemical transient transport phenomena in SOFC under various operational conditions, and that the applicability was confirmed by some numerical examples.

This paper aims to study the effects of MnO₂ on the ZnO–Bi₂O₃-based varistor prepared via flash sintering (FS)

MnO₂-doped ZnO–Bi₂O₃-based varistors were successfully prepared by the FS with a step-wise increase of the .current in 60 s at the furnace temperature <750°C under the direct current electric field of 300 V cm⁻¹. The FS process, microstructure and the electrical performance of ZnO–Bi₂O₃-based varistors were systematically investigated.

The doping of MnO₂ significantly decreased the onset temperature of FS and improved the electrical performance of FS ZnO varistor ceramic. The sample with 0.5 mol% MnO₂ doping shows the highest improvement, with the nonlinear coefficient of 18, the leakage current of 16.82 µA, the threshold voltage of 459 V/mm and the dielectric constant of 1,221 at 1 kHz.

FS is a wonderful technology to enhance ZnO varistors for its low energy consumption, and a short sintering time can reduce grain growth and inhabit Bi₂O₃ volatilize, yet few research studies work on that. In this research, the authors analyzed the FS process and improved the electrical characteristics through MnO₂ doping.

This study aims to examine the moderating role of two product-related variables – product type and product involvement on the relationship between shelf-based scarcity (SBS) and purchase intention.

The authors used four 2 × 2 between-subject experiments to test the proposed moderation.

Results from the four experimental studies provide the following insights. SBS enhances customers’ purchase intentions for utilitarian products and decreases purchase intentions for hedonic products. The positive influence of SBS cues on purchase intentions is more pronounced for low-involvement products than for high-involvement products. Perceived popularity and perceived quality mediate the relationship between SBS and perceived consumption risk for utilitarian products but not hedonic products.

This study builds on prior research on scarcity by investigating the impact of product-related factors on the SBS-purchase intention relationship through the elaboration likelihood model.

The results suggest that retailers benefit from using SBS cues for utilitarian and low-involvement products to increase purchase intention. Retailers can avoid SBS cues for hedonic products to prevent them from seeming commonplace. Furthermore, retailers can boost purchase intentions by highlighting the popularity and quality of utilitarian and low-involvement products.

To the best of the authors knowledge, this is the first study to examine the interaction between SBS and product-related attributes, along with the serial mediation of perceived popularity, quality and consumption risk.