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The influence of a newly synthesised organic compound on the inhibition of corrosion of arsenical aluminium brass in a NaCl solution has been investigated using weight loss measurements, potentiodynamic polarization studies and impedance measurements. Different corrosion kinetic parameters obtained from polarisation studies reveal that the inhibition of corrosion of arsenical aluminium brass in NaCl is under mixed control. UV‐reflectance, X‐ray diffraction and scanning electron microscopic studies have also been carried out to understand the mechanism of inhibition of corrosion, and also the morphological changes on the surface of the alloy. The adsorption of this compound on the metal surface from 3.5% NaCl solution is found to obey Temkin’s adsorption isotherm.

The term microbiologically induced corrosion (MIC) appears to be very closely related to the composition of the bio‐film which harbours the micro‐organism. Formation of an initial slimy layer on immersed metallic substrates is the rate‐controlling parameter of bio‐fouling, as uninterrupted undesirable growth of bio‐films occurs over this layer. To contain this bio‐film problem, formation of an adherent layer of toxic and inhibited corrosion product, that interacts with biofilm, could be exploited. Deals with the preliminary interactions of a few copper‐based alloys, with mildly toxic alkaloid class‐inhibitive compounds, in a simulated marine environment. It is assumed that the toxic and inhibited corrosion product and bio‐film interaction layer will interfere with the formation of the initial slimy cover on the immersed surface, responsible for bio‐fouling. It is seen that these alkaloid compounds exert a limited response on the inhibition of copper‐based alloys like monel. Brucine appears to be a more effective inhibitor for the monel surface. Pre‐oxidation of the uninhibited brass surface and also post‐oxidation of the inhibited surface appear to consolidate the corrosion product bio‐film‐inhibitor interaction layers, indicating the compatibility of these alkaloid compounds to the probable thermal strains to be encountered in engineering services. This indicates the possibility of using these compounds in heat transfer devices, like heat exchangers, where seawater is used as coolant.

The purpose of this paper is not only to gauge the extent of technical efficiency in 31 state road transport undertakings (SRTUs) operating in India but also to explore the most influential factors explaining its variations across SRTUs.

Three popular data envelopment analysis (DEA) models, namely CCR, BCC and Andersen and Petersen's super‐efficiency models, have been utilized to compute various efficiency scores for individual SRTUs. A censored Tobit analysis is conducted to see which factors significantly explain the inter‐SRTU variations in efficiency.

The key findings of the DEA analysis are only five SRTUs define the efficient frontier, and the remaining 26 inefficient undertakings have a scope of inputs reduction, albeit by the different magnitude; the extent of average overall technical inefficiency (OTIE) in these SRTUs is to the tune of 22.8 percent, indicating that the sample SRTUs are wasting about one‐fourth of their resources in the production operations; managerial inefficiency (as captured by the pure technical inefficiency) is a relatively more dominant source of OTIE; and operation in the zone of increasing returns‐to‐scale is a common feature for most of the undertakings. The multivariate regression analysis using Tobit analysis highlights that the occupancy ratio is the most significant determinant for all the efficiency measures, and bears a positive relationship with overall technical, pure technical and scale efficiencies. Further, scale efficiency is also impacted positively by the staff productivity.

The results of this paper can be applied from management's perspective. The managers can assess the relative efficiency of their SRTUs in the industry and take corrective measures to improve efficiency by altering input‐output mix.

This paper provides more robust estimates of relative efficiency of the SRTUs and highlights the key determinants of overall technical efficiency.

The purpose of this paper is to study thickness dependent variation in microwave properties of the Mg_xMn_(0.9−x)Al_0.1Zn_0.8Fe_1.2O₄ (x=0.8, 0.9) thick films and enhancement of power efficiency of Ag thick film EMC patch antenna.

X‐band microwave properties of the Mg_xMn_(0.9−x)Al_0.1Zn_0.8Fe_1.2O₄ (x=0.8, 0.9) thick films were measured by superstrate technique using Ag thick film EMC patch antenna as the resonant element. The complex permittivity and permeability of these thick films were also measured by this technique. The microwave response of the EMC patch, complex permeability and permittivity of Mg_0.8Mn_0.1Al_0.1Zn_0.8Fe_1.2O₄ and Mg_0.9Al_0.1Zn_0.8Fe_1.2O₄ thick films and their thickness dependency were investigated.

The XRD patterns reveal the cubic spinel crystal system was obtained for both compositions. The crystallite size obtained was 134.68 nm for Mg_0.8Mn_0.1Al_0.1Zn_0.8Fe_1.2O₄ and 155.99 nm for Mg_0.9Al_0.1Zn_0.8Fe_1.2O₄ The superstrate technique has been used successfully to evaluate the complex permittivity and permeability of the ferrite thick films in the X band. The EMC patch also show thickness and composition dependent frequency agility and enhancement of power efficiency.

The complex permeability of Mg_xMn_(0.9−x)Al_0.1Zn_0.8Fe_1.2O₄ (x=0.8, 0.9) thick films measured by superstrate technique is reported in this paper. The superstrate of Mg_xMn_(0.9−x)Al_0.1Zn_0.8Fe_1.2O₄ (x=0.8, 0.9) thick films makes the Ag thick film EMC patch antenna frequency agile and power amplification is obtained.

Corrosion sensors and networks are the most effective techniques to obtain the corrosion information and recognize the corrosion status of reinforced concrete structures. However, reference electrode is the key element to provide the baseline for potential control of the corrosion monitoring sensors during corrosion measurement process. Therefore, the purpose of this paper is to provide the novel solid‐state reference electrode for the corrosion sensors.

A solid‐state Ag/AgCl reference electrode has been prepared. Furthermore, the performance of the reference electrode, such as stability, temperature response, anti‐polarization and influence of the concrete admixture, has been investigated.

The results indicate that the balance potential and the temperature coefficient of the reference electrode are 3.64±1mv (vs. SCE) at 25°C and −0.51 mv/°C±0.03 mv/°C, respectively. Furthermore, the polarization curve exhibits characteristics of three stages as the polarization current is in (−10μA/cm2,+10μA/cm2). Additionally, the reference electrode is insensitive to the concrete admixtures which include Na2SO4, NaCl, NaNO3 and NaNO2.

The research provides the key element for the corrosion monitoring sensors to integrate structural health monitoring system in future.

Inhibition of the corrosion of mild steel in 1‐5 N HCl and H₂SO₄ by a macrocyclic compound viz., tetramethyl‐dithia‐octaazacyclotetradeca hexaene (MTAT) was studied as a corrosion inhibitor by weight loss and electrochemical potentiodynamic polarization methods. The influence of temperature, immersion time and acid concentration was also studied in the presence of MTAT in HCl and H₂SO₄. The potentiodynamic polarization carried out in 1‐5 N HCl and H₂SO₄ in the absence and presence of inhibitor revealed that MTAT is a mixed inhibitor. MTAT exhibited better performance as a corrosion inhibitor in H₂SO₄ and its performance was further improved the addition of KI due to synergism. The adsorption of MTAT on the mild steel surface obeyed Temkin adsorption isotherm.

The purposes of this research are to examine the extent to which daughters view their mothers as consumption role models, the extent to which daughters serve as consumption role models for their mothers, and the extent to which external role models are shared by mothers and their adolescent daughters.

Two qualitative studies focused on mothers‐adolescent daughters‐vicarious role models interactions as drivers of consumption behaviors in Western cultures. Study 1 included 20 in‐depth interviews with mothers and their adolescent daughters (conducted separately). Study 2 included five of the original dyads interviewed jointly and observed in fashion stores.

Regarding adolescent daughters' use as role models and fashion markers for their mothers, most mothers confirmed that their adolescent daughters' fashion opinion was very important. Second, based on consumer socialization arguments, mothers served as role models for their adolescent daughters. Most dyads shop for fashion items together and in the same stores. Regarding the issue of cognitive versus chronological ages, the studies suggest that there is a gap between mothers' cognitive and chronological ages in support of cognitive age theory and the youthfulness ideal of Western cultures. Notably, such a gap mostly failed to materialize for adolescent daughters. Hence, consumption similarity appears to be driven more by the gap for mothers than the gap for daughters. Finally, external role models such as celebrities did not have a great influence on mothers or their adolescent daughters.

The research used in‐depth interviews with and in‐store observation of mothers and adolescent daughters. Future research might use similar interviews with younger daughters. Another extension of the work reported here that can provide triangulation for the findings is to change from a qualitative to a quantitative methodology.

Surface pretreatment of iron and its alloys to remove stains and inorganic contaminants on the metal surface undergoes dissolution by virtue of the strong acidic media thereby increasing its susceptibility to corrosion. The purpose of this study is to explore the corrosion mitigation prospects of green corrosion inhibitors on mild steel surface.

Corrosion inhibition performance of Garcinia gummi-gutta leaf extract (GGLE) was explored against mild steel in 1 M HCl solution using the weight-loss method, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) techniques. Surface characterization was carried out to study the mechanism of inhibitor action.

The concentration of GGLE varied from 100 to 6,000 ppm and the result indicates that corrosion inhibition efficiency was amplified by raising the inhibitor concentration. The maximum inhibition efficiency was 82.2% at 6,000 ppm concentration. EIS results show the development of a protective layer of inhibitor molecule over the metal surface and PDP demonstrates that the inhibitor operates as a mixed-type inhibitor. Scanning electron microscopy and atomic force microscopy were executed to assess the surface morphology and roughness, respectively.

To the best of the authors’ knowledge, so far, no studies have been reported on the corrosion inhibition performance of GGLE which is rich in many bioactive components especially hydroxyl citric acid. This work encompasses the corrosion inhibition capability of GGLE against mild steel in an acidic medium.

The synergistic influence caused by iodide ions on the inhibition of corrosion of mild steel in 0.5M H₂SO₄ in the presence of n‐hexyl amine (n‐HA) has been studied using potentiodynamic polarization, linear polarization and a.c impedance technique. n‐HA accelerates the corrosion of mild steel at lower concentrations but inhibits the corrosion at higher concentrations. The addition of iodide ions enhances the inhibition efficiency to a considerable extent. The adsorption of this compound is found to obey Temkin’s adsorption isotherm. The increase in surface coverage in the presence of iodide ions indicates that iodide ions enhance the adsorption of n‐HA on the metal surface. Defines and evaluates synergism parameter (S_I). Values of the parameter which are more than unity indicate the fact that the enhanced inhibition efficiency in the presence of iodide ions is only due to synergism and there is a definite contribution from the inhibitor molecule. n‐HA is then adsorbed by coulombic interaction on the metal surface, where iodide ions are already adsorbed, and thus reduces the corrosion rate.

As the leisure industry matures, it is important for marketers to have a clear understanding of why people choose to consume specific leisure services. The paper proposes that “timestyle”, or how a person customarily perceives and uses time, influences the choice of leisure goals and resultant leisure services. Individuals’ timestyles can be characterized in terms of social, temporal, planning, and polychronic orientations. Data from qualitative research suggest that all four dimensions of timestyle can have systematic effects on leisure choices. Knowledge of the timestyle concept and its antecedent influences should allow leisure marketers to better understand and target the motivations that underlie consumer decisions on leisure services.