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This paper aims to investigate the corrosion resistance of two types of coatings – one is ceria sol coating and the other is ceria sol coating modified by ZnO nanoparticles on 7075 aluminum alloy in 3.5% NaCl solution.

Aluminum alloys were dipped into ceria sol and ceria sol modified by ZnO nanoparticles separately and removed after 10 min from the solutions and dried at 110°C for 30 min and heated at 500 °C for 30 min to form the coatings. The coatings have been characterized by using field emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The EIS tests were performed in a corrosive solution of 3.5% NaCl.

The results showed that the coating of ceria sol modified by ZnO nanoparticles has higher corrosion resistance than the ceria sol coating and the bare sample. Also, the best efficiency is related to aluminum sample immersion after 1 h in NaCl corrosive solution for coating modified by ZnO nanoparticles.

In this research, the modification of ceria sol coating by ZnO nanoparticles had an effect on improving the corrosion behavior of aluminum alloy. It is also understood that modification of coatings is an effective parameter on corrosion resistance.

In spite of the growing interest in using corpora in language teaching and learning, applying computers and software (especially corpora software) is still new in second language teaching and learning. In addition, employing a learner corpus-based perspective in teaching metadiscourse features in International English Language Testing System (IELTS) writing tasks is not reported to the best knowledge of the researchers. Understanding and spotting this gap, the purpose of this paper is to utilize a learner corpus-based approach in teaching metadiscourse features and investigate its possible impacts on IELTS writing performance of the Iranian second language learners. Therefore, this study addressed the following research questions and hypotheses.

The current research utilized a quasi-experimental research design. In addition, this research used a learner corpus-based methodology. The corpus-based methodology was exploited to enable the researchers to have access to a large body of authentic language materials. In other words, a corpus-based methodology was used due to the fact that it made it possible for the researchers to elicit the metadiscourse features from a large number of authentic writing materials and to employ them during the treatment process with authentic examples.

The findings showed that there was a positive correlation between teaching metadiscourse features and writing performance of IELTS learners; in that, teaching metadiscourse features could soar the writing performance of the subjects. In addition, interactional metadiscourse features had more impact than interactive metadiscourse features on writing performance.

The results of this research can have useful implications for second language teachers and learners as well as researchers in learner corpus as they can learn the creation and application of learner corpora in second language teaching and learning.

This paper is value in that it uses corpus software and methodology in teaching metadiscourse features in writing section of IELTS test.

The paper aims to report a fire test conducted on a three-dimensional frame in order to investigate the behaviour of bare steel flush end-plate connections with relatively low thickness at elevated temperatures.

A half-scale model was fabricated and exposed to modified (scaled) ISO 834 heating curve using a semi-open furnace. The maximum temperature inside the furnace reached 1,026 °C.

The rotations of connections are reported and compared with those of a previous study on an exactly the same model with thick end-plates. Various modes of failure such as local buckling of the beams flanges and lateral-torsional buckling of beams were observed during the test. Finally, the structure collapsed after 29 min of heating due to the fracture of weld between one of the beams and one of its attached end-plates whilst the other beam had undergone a maximum deflection of 35 cm (≈ 1/6 span length). Other observed failure modes included bolt fracture, bolt thread stripping and large inelastic deformation of the end-plates.

Although the adoption of thin end-plates increased the rotational capacity of the connections, it did not improve the robustness of the structure under fire conditions.

This study aims to assess and decompose the sustainable development using the 17 sustainable development goals (SDGs) in Iran in 2018, for proposing agenda-setting of public policy.

It ranks the SDGs not only in Iran but also in the region and the world to reveal the synergetic effects.

Based on the results, subaltern-populace generally suffers from the hegemonic domination of ruling elite-bourgeois, lack of strong institutions, heterogeneous policy networks and lack of advocacy role of non-governmental organizations, due to no transparency, issues in law or no rule of law, no stringent regulation, rent, suppression and Mafia, all leading to corruption and injustice.

To stop the loop of corruption-injustice, Iran should homogenize the structure of the policy network. Furthermore, the failed SDGs of the three-geographic analysis are the same in a character; all of them propose SDG 3, good health and well-being as a serious failed goal.

In this regard, strong evidence is the pandemic Coronavirus, COVID 19 since 2019, due to its highly-disastrous consequences in early 2020 where the public policymakers could not adopt policies promptly in the glob, particularly in Iran.

In Iran, in addition to this, the malfunction of health is rooted in “subjective well-being” and “traffic deaths,” respectively. Concerning the transportations system in Iran, it is underscored that it is damaging the sustainable development from all the three pillars of sustainable development including, economic, social and environmental.

Herbal medicine has been used for the management of complications of diabetes. The purpose of this paper is to examine the anti-diabetic effects of Achillea millefolium extract on diabetic rats.

To this aim, 32 male Wistar rats were randomly assigned into four groups in which each group comprised eight rats. The four experimental groups were as follows: control group, diabetic control (DC) group (STZ; 50 mg/kg), diabetic rats, receiving 250 mg/kg hydro-alcoholic extract of the A. millefolium (DAM) and diabetic rats, receiving 5 mg/kg glibenclamide (DG). After 21 days of the treatment course, tissues of the kidney and blood samples were collected for histopathological, biochemical and molecular analysis.

The concentration of malondialdehyde (MDA) and glucose serum were markedly reduced in the DC group while significantly increased in DG and DAM groups (1.11 ± 0.57 to 19.4 ± 3.5 and 17.8 ± 1.2 p = 0.002 and 325 ± 0.18 to 223 ± 0.11 and 211 ± 0.32 p = 0.02, respectively). Also, the activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) were markedly reduced in the DC group while significantly increased in DAM and DG groups (9.1 ± 2.21 to 18.7 ± 3.81 and 14.9 ± 3.1 p = 0.03 and p = 0.02, respectively). The concentrations of creatinine, blood urea nitrogen (BUN) and urea were substantially decreased in DAM and DG groups as compared with the DC group (0.49 ± 0.02 to 0.27 ± 0.01 and 0.25 ± 0.01 p = 0.01, 15.6 ± 2.1 to 7.2 ± 0.68 and 8.6 ± 1.2 p = 0.02 and 114 ± 9.4 to 59.8 ± 5.2 and 64 ± 5.2 p = 0.03, respectively). Also, Bcl-2-associated X protein (BAX) expression was significantly decreased in DAM and DG groups as compared with the DC group (1.3 ± 0.32 to 0.91 ± 0.03 and 0.93 ± 0.02 p = <0.01) and Bcl-2 expression were significantly increased in DAM and DG groups as compared with the DC group (0.42 ± 0.05 to 0.88 ± 0.07 and 0.85 ± 0.06 p = 0.01).

Diabetes led to degenerative damages in the kidney of rats and increased the mRNA level of Bax, while treatment with A. millefolium could protect the kidney tissue against diabetes complications and increased the mRNA expression of Bcl-2. This study indicated that A. millefolium extracts not only improves renal function as a result of anti-oxidant activity but also modulates some biochemical factors in diabetic rats.

Mechanical and chemical properties of acrylic-melamine automotive clear coat in the presence of different percentages of well dispersed nano-layered sodium montmorillonite (Na-MMT) silicate particles were investigated. For this purpose, prepared dry clear coat film samples were subjected to the entire standard test series, usually carried out in automotive coating industry.

Effects of adding different percentages of nano-layered silicate on mechanical and chemical properties of acrylic-melamine automotive clear coat were investigated. To increase the compatibility of nanoclays with polymer matrix of clear coat, the surface of nanoclays was modified by benzalkonium chloride as a cationic surfactant. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used for characterization and comparison between clays before and after modification, and also after dispersion in coating. Prepared dry clear coat film samples subjected to the test series are usually carried out in automotive coating industry.

The results indicated that incorporation of 1 and 2 Wt.% of nano-layered silicate caused desired improvement in chemical and physical properties of the acrylic-melamine clear coat. Increasing the percentage of nanoclay to over 2 Wt.% caused damage in some properties such as hardness, cupping and gloss.

All materials and methods were used in this research are industrial grade. Therefore, the introduced modified clear coat sample has potential for commercial production as an automotive clear coat.

As far as it was searched in the literature, effects of adding nanoclay particles on mechanical and physical properties of different clear coats, such as epoxy clear coat, have been investigated in a few researches, but in this research, common and special tests which are necessary in automotive coating industry have been ignored. In the present study for the first time, acrylic-melamine clear coat was subjected to modification using nano-clay, and also, the most common industrial test methods were used for investigation of mechanical and chemical properties.

The purpose of this study is three-dimensional flow and heat transfer investigation of water/Al₂O₃ nanofluid inside a microchannel with different cross-sections in two-phase mode.

The effect of microchannel walls geometry (trapezoidal, sinusoidal and stepped microchannels) on flow characteristics and also changing circular cross section to trapezoidal cross section in laminar flow at Reynolds numbers of 50, 100, 300 and 600 were investigated. In this study, two-phase water/Al₂O₃ nanofluid is simulated by the mixture model, and the effect of volume fraction of nanoparticles on performance evaluation criterion (PEC) is studied. The accuracy of obtained results was compared with the experimental and numerical results of other similar papers.

Results show that in flow at lower Reynolds numbers, sinusoidal walls create a pressure drop in pure water flow which improves heat transfer to obtain PEC < 1. However, in sinusoidal and stepped microchannel with higher Reynolds numbers, PEC > 1. Results showed that the stepped microchannel had higher pressure drop, better thermal performance and higher PEC than other microchannels.

Review of previous studies showed that existing papers have not compared and investigated nanofluid in a two-phase mode in inhomogeneous circular, stepped and sinusoidal cross and trapezoidal cross-sections by considering the effect of changing channel shape, which is the aim of the present paper.

This chapter aims to identify, analyse, classify and rank the sustainability indices and internationalisation challenges of the footwear industry in the emerging economy of Iran. This would provide deeper decision-making insights into Iranian footwear businesses. First, a list of sustainability indices and internationalisation challenges was obtained by reviewing the literature. Then, a combination of multi-criteria decision-making (MCDM) approaches was implemented. The initial sustainability indices and internationalisation challenges were screened using the fuzzy Delphi method, keeping a total of 14 criteria. The best–worst method (BWM) was employed to weigh and rank the criteria. The interpretive structural modelling (ISM) technique and cross-impact matrix applied in MICMAC were employed to visualise the conceptual model based on the levels and classification of the important criteria for the internationalisation of the Iranian footwear industry. The 14 criteria were demonstrated to be important in internationalisation. The most critical sustainability indices were reducing hazardous substances in leather tanning and labour education and training. In contrast, exchange rate instability in Iran’s economy and strict chemical regulations for clothing and footwear were found to be the most important internationalisation challenges. Hence, these criteria should be considered in the internationalisation strategies of the Iranian footwear industry. A combined multilayer sustainable decision-making approach was used to analyse the Iranian footwear industry’s essential sustainability indices and internationalisation challenges. Furthermore, implications and insights are offered to footwear businesses for future decision-making.

This study aims to develop a price policy for fossil fuel consumption, as it is an effective instrument to manage the demand-side of energy economics.

This research estimates the demand elasticities of diesel, gasoline, fuel oil and kerosene by using static, dynamic and error-correction models in log-linear form.

The findings show that fossil fuel demand responds to price changes less than income changes, as fuel price is inelastic, but income is elastic. In that respect, the impact of price change decreases constantly with increasing energy price, followed by subsidy reform. Subsidy removal and price policy reformation is the UN recommendation for subsidizing countries, including Iran, to reduce fossil fuel consumption, whose intensity depends on the price elasticities.

As a result of this price policy, diesel, gasoline and liquefied petroleum gas prices should increase at least 1.8%–7.3%, 4.4%–6.4% and 7%–8.6%, respectively, and gradually within 2018–2030. The price policy improves all the pillars of sustainable development, including economy, environment and social (health). Overall, such a target can potentially save 3%–29% of diesel, 34%–56% of gasoline and 15%–20% of liquefied petroleum gas, as well as reduce 15%–40% of CO₂ emissions annually, and can save potentially more than 510,000 lives annually. Thus, the energy price policy can fundamentally improve sustainability.

The estimated elasticities outline the required prices to decrease the fossil fuels, according to the UN mitigation targets, as price policy recommendation.