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The purpose of this paper is to show the effect of cinnamoylmalononitrile (CMN) compounds on the corrosion inhibition of carbon steel in HCl and the effect of some substituent groups on the corrosion inhibition.

Several papers have been published (1900‐1999), which aimed to investigate and explain the effect of organic compounds on the corrosion inhibition process. Two methods were used to determine the corrosion rate, weight loss and galvanostatic polarization. Additionally, the effects of temperature and concentration of the inhibitors were studied. The thermodynamic parameters for the process were computed and discussed.

The paper finds that surface analytical techniques such as X‐ray photoelectron spectroscopy and Auger spectroscopy can shed more light, on the mechanism of corrosion inhibition.

The use of donating and withdrawing groups will improve understanding of the mechanisms of corrosion and inhibition. However, the paper does not use the technique of impedance measurement for comparison purposes.

Other steel alloys and compounds with large or small molecular weights can be used for comparison.

The use of CMN compounds as corrosion inhibitors for carbon steel in HCl provides more information on carbon steel corrosion for academic and starting researchers.

Passive design strategies contribute to improving indoor comfort conditions and reducing buildings' energy consumption. For several years, courtyards have received wide attention from researchers because of their significant role in reducing energy demand. However, the abundance of multi-story buildings and the courtyards' incompatibility with them, the courtyard is currently limited. Therefore, it is necessary to search for alternatives. This paper aims to bridge the gaps in previous limited studies considering skycourt as a passive alternative on the vertical plane of the facades in contrast to the courtyard.

This research presents an overview and a bibliometric analysis of the evolution of the courtyard to the skycourt via VOSviewer software and the bibliometrix R package.

The research provided various concepts related to skycourt as a promising passive design strategy, which can be suitable for multi-story buildings, starting with its evolution, characteristics, configurations, benefits, and challenges.

The findings can urge designers, researchers and policymakers to incorporate such an important passive alternative.

Researchers, instructors, educational specialists, faculty members, and decision-makers can provide design motivation for skycourt in buildings, in addition to achieving awareness about skycourt and its significant benefits and its role as an important passive design strategy.

The research highlights the possibilities of the skycourt and its role as a passive design element as an extension of the courtyard in addition to identifying design indicators that help designers determine the appropriate designs.

The purpose of this paper is to study the corrosion inhibition performance of an eco-friendly drug clozapine on the corrosion of copper in 1.0 M nitric acid and 0.5 M sulfuric acid solutions.

The corrosion inhibition nature of inhibitor molecule was evaluated by weight loss, electrochemical impedance spectroscopy and potentiodynamic polarization studies. An attempt was made to correlate the molecular properties of neutral and protonated forms of inhibitor molecule using quantum chemical calculations. The effect of temperature on the corrosion inhibition efficiency was also studied using electrochemical impedance spectroscopy. The potential of zero charge was determined to explain the mechanism of corrosion inhibition.

The studies on corrosion inhibition performance of clozapine showed that it has good corrosion inhibition efficiency on the corrosion of copper in 1.0 M nitric acid and 0.5 M sulfuric acid solutions. The adsorption of clozapine molecules onto the copper surface obeyed the Langmuir adsorption isotherm. The value of free energy of adsorption calculated is very close to −40 kJmol⁻¹, indicating that the adsorption is through electrostatic coulombic attraction and chemisorption. The decrease in the value of energy of activation with the addition of inhibitor also shows the chemisorption of the inhibitor on the metal surface. The potential of zero charge and quantum chemical studies confirmed that the protonated molecules also get involved in the corrosion inhibition process through physisorption.

The present work indicates that clozapine can act as a good corrosion inhibitor for the corrosion of copper in acid media.

Lot-sizing is among the most important problems in the production and inventory management field. The purpose of this paper is to move one step forward in the direction of the real environment of the dynamic, multi-period, lot-sizing problem. For this purpose, a two-warehouse inventory system, imperfect quality and supplier capacity are simultaneously taken into consideration, where the aim is minimization of the system costs.

The problem is formulated in a novel continuous nonlinear programming model. Because of the high complexity of the lot-sizing model, invasive weed optimization (IWO), as a population-based metaheuristic algorithm, is proposed to solve the problem. The designed IWO benefits from an innovative encoding–decoding procedure and a heuristic operator for dispersing seeds. Moreover, sequential unconstrained minimization technique (SUMT) is used to improve the efficiency of the IWO.

Taking into consideration a two-warehouse system along with the imperfect quality items leads to model nonlinearity. Using the proposed hybrid IWO and SUMT (SUIWO) for solving small-sized instances shows that SUIWO can provide satisfactory solutions within a reasonable computational time. In comparison between SUIWO and a parameter-tuned genetic algorithm (GA), it is found that when the size of the problem increases, the superiority of SUIWO to GA to find desirable solutions becomes more tangible.

Developing a continuous nonlinear model for the concerned lot-sizing problem and designing a hybrid IWO and SUMT based on a heuristic encoding–decoding procedure are two main originalities of the present study.

The purpose of this study is to develop and investigate a fast and accurate algorithm for the modeling of characteristic impedance of double-layer coaxial waveguides.

This paper presents the newly developed numerically stable analytical formula for calculation of the characteristic impedance of double-layer coaxial conductor and its elements such as resistance, inductance, capacitance and conductance per unit length. The formula contains modified scaled Bessel functions. The results of the developed analytical formula were compared with results obtained from the axis-symmetric 2D and 3D finite element method (FEM) simulations, using three different solvers.

The proposed method shows a good agreement between results obtained with the new fast and stable analytical model and particular FEM models, selected depending on frequency range. The relative difference between characteristic impedance calculated using the new analytical method and obtained from chosen FEM method for discussed frequency range is less than 0.1 per cent which proves the correctness of the new analytical formula. Noteworthy is the fact that the relative difference of the resistance computed using the developed analytical method and obtained with Maxwell FEM solver for the frequency in range from 1 Hz to 10 MHz is less than 0.01 per cent. The presented work shows that when the calculations are performed over wide frequency range, it is necessary to use more than one solver, especially when the wavelength is comparable with dimensions of the conductor. The computation time of the new analytical model is much shorter than the computation time of FEM.

An efficient, numerically stable algorithm for computation of characteristic impedance of a double-layer coaxial conductor (waveguide).

This paper aims at examining the potentiality of using Hibiscus sabdariffa L. calyces’ (Hs) aqueous extract to remove soot stains from the surface of fire-damaged silver gelatin prints. It further studies the cleaning efficiency and impact of both a contact method and a noncontact method with argon dielectric barrier discharge plasma (DBD Ar. plasma) on the different properties of silver gelatin prints. Accordingly, it prompts using economic, eco-friendly materials and methods in the photograph conservation field.

To achieve the aims of this paper, four silver gelatin prints were stained with soot and treated with the Hs aqueous extract as a contact method and DBD Ar. plasma combined with the aqueous extract as a noncontact method. The assessment was carried out using digital microscopy, atomic force microscopy and spectrophotometer to study the efficiency of the tested treatments and their impact on the surface of the photographs. Fourier transform infrared was used to monitor the state of the binder after cleaning. Furthermore, the pH and the mechanical properties were measured.

The contact method resulted in lower concentrations of Hs extract that efficiently cleaned the surface without causing any stains or damage to the treated photographs. The noncontact method (plasma with an aqueous extract) proved to be less effective in cleaning and made the binder more susceptible to deterioration.

This paper reveals the success of Hs aqueous extract in cleaning soot on vulnerable photographs' surfaces.

Online learning has many limitations in studio-based courses, such as architectural design courses, considering the challenges during post-pandemic. Therefore, this study aims to propose a post-pandemic adopted learning approach, which integrates flipped classrooms (FC) with project-based learning (PBL). In addition, this study evaluates the perceptions of students based on and the effects of the proposed learning approach in architectural design.

This study provides a mixed methodology based on a literature review on the topic to bridge the gaps in previous studies regarding the FC and PBL. In addition, a case study survey including semi-structured interviews, observations questionnaire recruited undergraduate students to generate both qualitative and quantitative data to investigate the perceptions of students based on post-pandemic adopted learning approach.

This study has highlighted the significance of post-pandemic adopted hybrid learning method, especially in architectural education, whereas the research finds that FC is an appropriate solution to improve design courses with online technologies.

The proposed approach provides specialists to develop and integrate proposals and strategies to enable a better online practice for students and instructors. The proposed approach can enhance the students' interpersonal skills, hence active online learning related architectural design projects.

Recognizing the significance of e-learning in response to the post-pandemic scenario, this study developed and assessed new learning technique that combines online learning with traditional design studios via hybrid learning method.

The question is whether debt market investors see through managers' attempts to hide their pension obligations. The authors establish a robust relation between understated pension liabilities and corporate bond yield spreads after controlling for factors that have been previously identified as having a significant impact on firms' cost of borrowing. The results support the idea that bond market investors are not being misled by the use of high pension liability discount rates by some companies to lower their reported pension obligations. For a small fraction of debt issuers, the reported pension liabilities are larger than the pension liabilities valued at the stipulated interest rate benchmarks. For these issuers with overstated pension liabilities, bond investors adjust their borrowing costs downward.

The authors investigate the relation between corporate bond yield spreads and understated pension liabilities relative to long-term Treasury and high-grade corporate bond yields. They aim to answer two questions. First, what are the sizes of over or understated pension liabilities relative to guideline benchmarks? Second, do debt market investors see through the potential management manipulation of pension discount rates? The authors find that firms with large understated pension liabilities face higher marginal borrowing costs after taking into account issue-specific features, firm characteristics, macroeconomic conditions and other pension information such as funded status and mandatory contributions.

The average understated projected benefit obligations (PBOs) are understated by $394.3 and $335.6, equivalent to 3.5 and 3.0% of the beginning of the fiscal year market value, respectively. The average understated accumulated benefit obligations (ABOs) are understated by $359.3 and $305.3 million, equivalent to 3.1 and 2.6%, of the beginning of the fiscal year market value, respectively. Relative to AA-grade corporate bond yields, the average difference between firm pension discount rates and benchmark yields becomes much smaller; the percentage of firm pension discount rates higher than benchmark yields is also much smaller. As a result, understated pension liabilities become negligible. The authors establish a robust relation between corporate bond yield spreads and measures of understated pension liabilities after controlling for issue-specific features, firm characteristics, other pension information (funded status and mandatory contributions), macroeconomic conditions, calendar effects and industry effects.

S&P Rating Services recognizes the issue that there is considerably more variability in discount rate assumptions among companies than in workforce demographics or the interest rate environment in which firms operate (Standard and Poor's, 2006). S&P also indicates that it would be desirable to normalize different discount rate assumptions but acknowledges that it is difficult to do so. In practice, S&P Rating Services conducts periodic surveys to see whether firms' assumed discount rates conform to the normal standard. The paper makes an initial attempt to quantify the size of understated pension liabilities and their impact on corporate bond yield spreads. This approach can be extended to study firms' costs of equity capital, the pricing of seasoned equity offerings and the pricing of merger and acquisition transaction deals, among other questions.

The performance of different pretreatment‐primer systems for hot‐dip galvanized (HDG) and Galfan coated steel has been studied. The materials were pretreated with three pretreatment processes; an alkaline oxide pretreatment with either a chromate or a zirconium based post‐rinse, and a zinc phosphating pretreatment. After the pretreatment, the panels were coated with four commercially available primers. The chemically treated substrates were characterized by using ESCA and GD‐OES, and the cured paint films by using FTIR. Paint adhesion of primed panels was determined with a combined cross‐cut and impact test and also with the NMP test. Formability of the panels was tested by T‐bend test and corrosion resistance with a cyclic prohesion test. According to the prohesion test results, primed Galfan coated panels have better edge corrosion resistance than primed HDG panels. Test results also show that the effect of pre‐treatment is not as significant for the corrosion resistance as the effect of primer. However, in the case of zinc phosphated samples, excellent synergistics between the pretreatment and two of the primers was detected.

Fingerprints and blood samples are important for the identification of individuals and criminals. The present study aims to identify the predominant fingerprint patterns and the association between the fingerprint patterns and ABO–Rh blood groups in Omani population.

A cross-sectional study was conducted on 200 Omani individuals aged 18 years (104 males and 96 females). The imprints of all right and left-hand fingers were taken, and the types of the fingerprints were determined using a standard protocol. The blood group of all the subjects was recorded. Chi-square test was performed to identify the association between the fingerprint patterns and the ABO and Rh blood groups.

The loop fingerprint pattern was the most common in Omani subjects (49.4%), followed by whorl (44.9%) and arch (5.7%) pattern. A significant association (p < 0.001) was found between gender and fingerprint pattern. The loop was the highest occurring pattern in the females (54.6%), while the whorl was more in males (50.0%). The whorl pattern was the most common in the AB+ and O− groups. The loop was a predominant pattern in the A+, A−, B+, B− and O+ groups. The Chi-square test also revealed a significant correlation between different fingerprint patterns and blood groups of the subjects (p < 0.001).

The present study is an outcome of undergraduate student's research project thesis for the Doctor of Medicine (MD) program. The results of the present study may help in creating a data bank for biometrics, which can be useful for diagnosing associated diseases and also help in identification of individuals.