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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.

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.

In this paper, using experimental results [1], empirical equations [2], and the concept of effective carriers while hopping in ionic conduction, an alternative explanation is discussed for open circuit voltage (OCV) using Sm‐doped Ceria electrolytes (SDC) in solid oxide fuel cells (SOFCs). Consequently, one chapter of the standard textbook [3] must be entirely modified. This alternative explanation not only coexists with major existing experimental results but also is useful for explaining minor experimental results. An experimental method is proposed to clarify the theoretical consideration.

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.

This intensified case finding study aimed to evaluate the prevalence of tuberculosis (TB) disease among people with HIV entering the largest prison in Malaysia.

The study was conducted in Kajang prison, starting in July 2013 in the men’s prison and June 2015 in the women’s prison. Individuals tested positive for HIV infection, during the mandatory HIV testing at the prison entry, were consecutively recruited over five months at each prison. Consented participants were interviewed using a structured questionnaire and asked to submit two sputum samples that were assessed using GeneXpert MTB/RIF (Xpert) and culture, irrespective of clinical presentation. Factors associated with active TB (defined as a positive result on either Xpert or culture) were assessed using regression analyses.

Overall, 214 incarcerated people with HIV were recruited. Most were men (84.6%), Malaysians (84.1%) and people who inject drugs (67.8%). The mean age was 37.5 (SD 8.2) years, and median CD4 lymphocyte count was 376 cells/mL (IQR 232–526). Overall, 27 (12.6%) TB cases were identified, which was independently associated with scores of five or more on the World Health Organization clinical scoring system for prisons (ARR 2.90 [95% CI 1.48–5.68]).

Limited data exists about the prevalence of TB disease at prison entry, globally and none from Malaysia. The reported high prevalence of TB disease in the study adds an important and highly needed information to design comprehensive TB control programmes in prisons.

The present study aims to encompass the bidirectional magnetized flowing of a hybrid-nanofluid over an unsteady stretching device with the inclusion of thermal radiation and entropy generation. Brick-shaped nanoparticles (zinc-oxide and ceria) are suspended in water, serving as the base-fluid to observe the performance of the hybrid mixture. The Maxwell thermal conductivity relation is employed to link the thermophysical attributes of the hybrid mixture with the host liquid. Additionally, a heat source/sink term is incorporated in the energy balance to enhance the impact of the investigation. Both prescribed-surface-temperature (PST) and prescribed-heat-flux (PHF) conditions are applied to inspect the thermal performance of the hybrid nanofluid.

The transport equations in Cartesian configuration are transformed into ordinary differential equations (ODEs), and an efficient method, namely the Keller-Box method (KBM), is utilized to solve the transformed system. Postprocessing is conducted to visually represent the velocity profile, thermal distribution, skin-friction coefficients, Bejan number, Nusselt number and entropy generation function against the variations of the involved parameters.

It is observed that more entropy is generated due to the increases in temperature difference and radiation parameters. The Bejan number initially declines but then improves with higher estimations of unsteadiness and Hartmann number. Overall, the thermal performance of the system is developed for the PST scenario than the PHF scenario for different estimations of the involved constraints.

To the best of the authors' knowledge, no investigation has been reported yet that explains the bidirectional flow of a CeO2-ZnO/water hybrid nanofluid with the combined effects of prescribed thermal aspects (PST and PHF) and entropy generation.

This paper aims to introduce constructed CeO2/TiO2 core/shell nanoparticle as sensitive substance organic compounds.

The CeO₂ nanoparticles were synthesized by hydrothermal treatment. Then CeO₂/TiO₂ core/shell was fabricated by sol–gel method preparation of TiO₂ in the presence of ceria nanoparticles and applied as the sensitive material to make a sensor.

Formation of the nanoparticles was confirmed by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM). The synthesized sensor exhibited not only good sensitivity to volatile organic compounds at room temperature but also logarithm of sensitivity versus concentrations was linear.

The sensor shows acceptable sensitivity to volatile organic compound at room temperature.

Experimental data revealed satisfactory reproducibility and short response and recovery times.

A radical mechanism for gas sensor reaction in two pathways was considered and activation energies were calculated by density functional theory (DFT) method to describe different sensitivities of tested volatile gases. The experimental results were consistent with the calculations.

This research aims to deal with the law of evidence invoked in Islamic banking cases reported in Malaysia from 1983 to 2015 and determine whether the invoked provisions of the statute in the case law have any conflicts with Islamic law that are threatening the development of Islamic banking in Malaysia.

The methodology used in this research is assessing the implication by studying the provisions of the law of evidence that has been invoked in the reported case law.

It is evident from this research that following are the evident conflicts found in the Evidence Act 1950. In this arena, the following changes are significant for sustaining Islamic banking in Malaysia. Expert opinion under Section 45 of the Evidence Act 1950 should be amended such that in Islamic banking, under this Act, expert opinion can be sought by the court. The rule and exceptions of parol evidence in Sections 91 and 92 of the Evidence Act 1950 need to be amended such that in Islamic banking matters, anything that is contrary to Shari^cah is mentioned in the contract; this amendment will be an exception to the parol evidence rule on the grounds that the written Islamic contract can be amended or set aside depending on the circumstances of the case.

It is anticipated that this research will assist jurisdictions to understand that even adjective laws applicable to Islamic banking will be harmonized with Islamic law. This is because the prefix Islam attached to the term banking is not merely a namesake, but it means more than that, i.e. all aspects of Islamic banking will be consistent with Islamic law.