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This paper mainly aims to study the influence of some thiosemicarbazides, namely, 1‐hydroxyphenyl‐4‐phenyl thiosemicarbazide (HPT), 1,4‐diphenyl thiosemicarbazide (DPT), 1‐aminophenyl‐4‐phenyl thiosemicarbazide (APT) and 1‐cinnamyl‐4‐phenyl thiosemicarbazide (CPT) on the corrosion inhibition of carbon steel in hydrochloric and sulphuric acid.

All inhibition experiments were conducted on carbon steel in 1N HCl and 1N H₂SO₄ solution. Weight loss experiments were carried out according to the ASTM standard procedure. Polarization studies were carried out in a three‐electrode cell assembly connected to an EG&G Princeton applied research potentiostat/galvanostat (model 173).

For all the compounds a consistent trend of increase in inhibition efficiency was observed as a function of inhibitor concentration. The adsorption of all the compounds on to the carbon steel surface in the acidic solution was found to obey the Tempkin's adsorption isotherm. The values of activation energy and free energy of adsorption for all the compounds were also calculated. Polarization measurement revealed that the studied thiosemicarbazides act predominantly as mixed inhibitors in both the acid solutions, with the exception of DPT, which predominantly behaved as a cathodic inhibitor in 1N HCl.

These inhibitors could have application in industries, where hydrochloric and sulphuric acid solution are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

This paper reveals that thiosemicarbazides can be successfully used for protection of carbon steel corrosion in acid solutions.

Answering to calls for further contextualizing global leadership, this study investigates power dynamics and cultural identities in global leadership in an African context. We took a grounded theory approach to investigate how a specific cultural context shapes assets and liabilities of global leaders. Drawing on our data comprising semi-structured interviews of managers of multinational enterprises operating in Ghana, we identified key assets and liabilities for being local or foreign in one’s global leadership role. Furthermore, we theorize four specific styles of leadership leveraging: identity leveraging, power leveraging, juxtapositional leveraging, and temporal leveraging. Finally, we integrated the above-mentioned elements and proposed a framework of contextualized assets and liabilities which illustrates how specific cultural context affects the assets and liabilities of localness and foreignness for global leaders, and how these assets and liabilities constitute the four styles of leveraging in such context. Implications of our findings for research and practice are discussed.

This article explores the use of informal socio-cultural practices to mitigate formal institutional voids in a qualitative study of informal self-employment in Bulawayo in Zimbabwe. Informal socio-cultural values and practices such as ubuntu and indaba were observed to be making meaningful contribution to business and lives. Development of formal institutions as a consequence was not observed though. The article proposes that economic development efforts might best serve communities in sub-Saharan Africa by facilitating institutional development that converges with local socio-culturally informed practices rather than focus on attempts to absorb informal work into a homogenously understood formal institutional system.

Advancement in optimization of VLSI circuits involves reduction in chip size from micrometer to nanometer level as well as fabrication of a billions of transistors in a single die where global routing problem remains significant with a trade-off of power dissipation and interconnect delay. This paper aims to solve the increased complexity in VLSI chip by minimization of the wire length in VLSI circuits using a new approach based on nature-inspired meta-heuristic, invasive weed optimization (IWO). Further, this paper aims to achieve maximum circuit optimization using IWO hybridized with particle swarm optimization (PSO).

This paper projects the complexities of global routing process of VLSI circuit design in mapping it with a well-known NP-complete problem, the minimum rectilinear Steiner tree (MRST) problem. IWO meta-heuristic algorithm is proposed to meet the MRST problem more efficiently and thereby reducing the overall wire-length of interconnected nodes. Further, the proposed approach is hybridized with PSO, and a comparative analysis is performed with geosteiner 5.0.1 and existing PSO technique over minimization, consistency and convergence against available benchmark.

This paper provides high performance–enhanced IWO algorithm, which keeps in generating low MRST value, thereby successful wire length reduction of VLSI circuits is significantly achieved as evident from the experimental results as compared to PSO algorithm and also generates value nearer to geosteiner 5.0.1 benchmark. Even with big VLSI instances, hybrid IWO with PSO establishes its robustness over achieving improved optimization of overall wire length of VLSI circuits.

This paper includes implications in the areas of optimization of VLSI circuit design specifically in the arena of VLSI routing and the recent developments in routing optimization using meta-heuristic algorithms.

This paper fulfills an identified need to study optimization of VLSI circuits where minimization of overall interconnected wire length in global routing plays a significant role. Use of nature-based meta-heuristics in solving the global routing problem is projected to be an alternative approach other than conventional method.

This chapter addresses growing concerns that, despite being a radically intentioned community, Critical Management Studies (CMS) lacks an orientation to achieve pragmatic change. In response I argue that the failure to address the continuing marginalisation of the subaltern is key to CMS being negatively represented as an elitist self-preoccupied endeavour. This state of affairs is linked to a legacy of the ‘postmodern’ turn, which emerged in the 1980s and 1990s, as evidenced by the nature of contemporary debates continuing to reflect the stylistic fetishes of that time. I contend that the ghost of postmodernism is evident in the continuing predilection to produce signification discourses marked by symbolic absences, which politically confine such texts to the level of epistemology. The lack of integration of ontological concerns means that corporeal aspects of daily life are neglected, resulting in an abstracted ‘subjectless’ mode of representation. To address these limitations, a feminist activist version of post-structuralism (PSF) of the time is revisited, which through its distinctive attention to community concerns, enabled the linking of epistemological and ontological representations; thereby facilitating the creation of a framework for pragmatic change. As the chapter demonstrates, by drawing attention to the integral relationship between the modes of representation, power relations and subsequent social effects, poststructuralist feminists were able to achieve praxis outcomes. Accordingly, I argue this treasure house of ideas needs to be reclaimed and provides illustrations of the design principles proffered to support my contentions.

Mental health problems during the initial years of life are precursors of mental disorders in later life, as well as poor quality of life. However, understanding and assessing the quality of life among children is very challenging and requires appropriate assessment measures. Against this backdrop, this study aims to establish the evidence for the construct and convergent validity of Urdu version of Pediatric Quality of Life Inventory (PedsQL) in Pakistani children.

This study has a cross-sectional study design in which a sample of 291 primary school children (53.3% male children and 44.7% female children) were enrolled from 6 primary schools located in Rawalpindi District in 2021 through random sampling. Children’s ages ranged between 9 and 13 years (M = 10.51 years; SD = 0.73). Urdu translated version PedsQL, Rosenburg self-esteem scale (RSES), strengths and difficulties questionnaire (SDQ), difficulty subscale and socio-demographic form were administered in a group setting.

Confirmatory factor analysis showed model provided a better fit similar to three factors: social/school functioning; psychological functioning; and physical functioning with good alpha reliability for full scale as well for subscales (r = 0.87, r = 0.75, r = 0.77 and r = 0.73), respectively. Pearson’s correlation of the translated version with SDQ_difficulties (r = −0.33; p < 0.01) and RSES (r = −016; p < 0.01) depicted solid discriminant validity (r = −0.33; p < 0.01) and RSES showed good convergent validity (r = −0.16; p < 0.01). Hence; PedsQL, Urdu proved to be a reliable, valid and efficient tool for the assessment of quality of life among Pakistani children, and its three-factor structure model suggested previously for Pakistani children was confirmed.

This study is original work by the researcher as part of their PhD project.

The purpose of this paper is to study the inhibitory activity of benzene‐1,2,4,5‐tetracarboxylic dianhydride (PMDH) on aluminium corrosion in hydrochloric acid 1 M HCl.

The inhibitive effect of PMDH towards the corrosion of aluminium in 1 M HCl solution is studied by means of electrochemical impedance spectroscopy, polarization curves (LSV) and scanning electron microscopic techniques. The effect of inhibitor concentration and temperature against inhibitor action is investigated.

In the presence of inhibitor (PMDH), the corrosion resistance of aluminium is improved and the corrosion rate and corrosion current are reduced, therefore the inhibition efficiency and polarization resistance are increased. With increasing temperature and decreasing inhibitor concentrations, the rate of aluminium corrosion increased. The surfactant acts as mixed type inhibitor and obeys a Langmuir isotherm.

The results shown in this paper are an insight to the understanding of the corrosion resistance and electrochemical behaviour of aluminium for future industrial applications and development.

Copper and its alloys are widely used in industries because of their good resistance to corrosion and are often used in cooling water systems. Brass has been widely used for shipboard condensers, power plant condensers and petrochemical heat exchangers. Brass is susceptible to the corrosion process known as dezincification by means of which brass looses its valuable physical and mechanical properties leading to failure of structure. The aim of this investigation was to control the dezincification of brass in 3 per cent NaCl solution using benzotriazole (BTA) derivatives.

BTA derivatives namely 1‐hydroxymethylbenzotriazole (HBTA) and N,N‐dibenzotriazol‐l‐ylmethylamine(ABTA) were synthesised and their inhibition behaviour on brass in 3 per cent NaCl solution was investigated by the weight‐loss method, potentiodynamic polarisation, electrochemical impedance and solution analysis techniques. The morphology of the brass after corrosion in the presence and absence of the BTA derivatives was examined using scanning electron microscopy (SEM).

Potentiodynamic polarisation studies showed that the BTA derivatives investigated were mixed type inhibitors, inhibiting the corrosion of brass by blocking the active sites of the brass surface. Changes in the impedance parameters (charge transfer resistance and double layer capacitance) were related to the adsorption of BTA derivatives on the brass surface, leading to the formation of a protective film. Solution analysis revealed that the BTA derivatives excellently controlled the corrosion of brass. SEM micrographs showed the formation of compact surface film on the brass surface in the presence of inhibitors, thereby providing better corrosion inhibition.

Contributes to research on corrosion protection for copper and its alloys.

Following Braudel's conceptualization of capitalism and Arrighi's periodization of systemic cycles of accumulation, the authors focus on the patterns of recurrence of financial expansions enabling capitalism to revitalize itself through crisis; in this, crisis is considered in both aspects — crisis‐as‐restructuring and crisis‐as‐rupture. The ways in which finance aided by the blocks of governmental and business agencies in the present stage affects investment and business cycles result in a progressive increase of inequality between rich and poor countries, as well as inequality within the most developed countries. The authors tackle the crisis phenomenon through a genealogical analysis of the formation, consolidation and disintegration of the successive regimes of accumulation on a world scale through which the capital economy expands. They furthermore examine the crisis of capitalist accumulation through the relation of money and the state, which leads them to the field of debates on the changed relationship between the global economy and the national state. However, the crisis is also marked by a milestone which, despite dangers and pitfalls, opens up endless possibilities. They end the paper with a critique of the politics of money and advocate a socially responsible finance management, which will pave the way for a structure of society in which humanity will exist as an end in itself, rather than as a resource for the accumulation of money.

This paper aims to examine the dynamic nexus between corporate governance (CG) and firm performance in hybrid model countries. It also investigates the effect of horizontal agency conflicts on CG adherence.

This research uses vector autoregression methods and dynamic panels to examine the cross-sectional and longitudinal association between CG and performance, using three CG adherence indexes of transparency, management and board governance. The data set includes annual market and firm performance data from a sample of 93 companies trading in the Mexican stock market for the period 2010–2016.

This study finds evidence of dynamic interdependence between CG and firm performance, as well as weak effects of CG adherence on firms’ performance. The adverse effect of increasing return on equity and return on assets (ROE-ROA) gaps on CG adherence, which results from agency conflicts and insider ownership, is likely behind the weak association between CG and firm performance.

The findings in this study provide evidence that hybrid systems weaken the nexus between CG and firm performance. The propensity to prefer banking and bond debt to issuing stocks, as indicated by a greater ROE-ROA gap, points to favorable provisions for majority shareholders, adverse normative environments for minority shareholders and a low level of compliance with CG measures, among other problems.