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This work aims to analyze the effect of mechanical activation on structural disordering (amorphization) in an alumina-silica ceramics system and formation of mullite most notably at a lower temperature using X-ray diffraction (XRD). Also, an objective of this work is to focus on a low-temperature fabrication route for the production of mullite powders.

A batch composition of kaolin, alumina and silica was manually pre-milled and then mechanically activated in a ball mill for 30 and 60 min. The activated samples were sintered at 1,150°C for a soaking period of 2 h. Mullite formation was characterized by XRD and scanning electron microscopy (SEM).

It was determined that the mechanical activation increased the quantity of the mullite phase. SEM results revealed that short milling times only helped in mixing of the precursor powders and caused partial agglomeration, while longer milling times, however, resulted in greater agglomeration.

It is noted that, a manual pre-milling of approximately 20 min and a ball milling approach of 60 min milling time can be suggested as the optimum milling time for the temperature decrease succeeded for the production of mullite from the specific stoichiometric batch formed.

A structural and textural characterization study has been performed to investigate the adherence of zeolite-based catalyst washcoated onto honey-comb-type cordierite monoliths. The supports were characterized by the scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD) and Brunauer–Emmett–Teller (BET) techniques.

SEM/EDS provided quantitative estimate of the washcoated monolith as the elemental composition of catalyst coating. The XRD pattern deduced that the zeolite-based catalysts were successfully mounted on the cordierite support, showing the characteristic peaks of zeolites (Zeolite Socony Mobil–5; ZSM-5) at Braggs angles of 7.88°, 8.76°, 23.04°, 23.88° and 24.36°, whereas the characteristic peak of cordierite is seen at a Braggs angle of 10.44°.

The BET results proved that a monolayer of zeolite may serve the need for surface area and porosity. This was evident in the increase of surface area of washcoated support as against the bare support. The obtained isotherms were of Type IV, illustrating the presence of mesopores. The adsorption and desorption isotherm branches coincided over the interval 0 < P/P0 < 0.50 and 0 < P/P0 < 0.45, showing N₂ reversible adsorption for the two samples, respectively.

It was concluded that the composite materials which are ZSM-5 (Si/Al = 25) and precursors of the transition salts of copper, zinc and ceria powders were deposited on the catalyst supports, establishing the success of the coating procedure relative to the adherence of the catalyst compositions on the ceramic support.

Small- and medium-sized enterprises (SMEs) within the construction sector are highly vulnerable to disruptions caused by political and economic decisions or even pandemics. This study evaluated the current operations of selected SMEs providing engineering design and consultancy services against Toyota Production System (TPS) lean tool. The purpose is to juxtapose SME operations and processes with TPS to ascertain the level of their operations conformity to the established TPS lean thinking tool.

This study used a qualitative data collection and analysis approach to evaluate the current processes of participating SMEs against Liker's 14 management principles of TPS. The data collected were analysed using thematic analysis to identify patterns and themes that emerged from the qualitative data.

The analysis revealed that focus on short-term goals, immediate profit and duplication of effort resulting from insufficient collaboration is currently creating waste in participating SMEs' operations. Hence, the implementation of TPS was recommended as a lean tool and a framework based on TPS lean tool was developed for improving the operations of SMEs.

The study is limited to SMEs operating only as consultants providing project planning design within the construction industry. Data collection is limited to qualitative even though observations would improve the outcome of the study.

The study advances contemporary issues in promoting lean implementation in construction sector and developed an improved framework based on the TPS to enhance the performance of SME construction businesses.

Extant studies have discussed numerous carbon reduction drivers, but there is a dearth of holistic review and understanding of the dynamic interrelationships between the drivers from a system perspective. Thus, this study aims to bridge that gap.

The study conducted a review using Preferred Reporting Items for Systematic Reviews and Meta-Analyses and adopted interpretive structural modelling (ISM) to analyse and prioritise the drivers.

Eighteen drivers were identified and grouped into five, namely, policy instruments, bid-related, cost and risk, education and training, and reward and penalty drivers. The ISM revealed two hierarchical levels of the drivers with only higher cost of electricity/fuel on the higher level, making it the most important driver that could influence others.

The study presents an overview of decarbonisation drivers in the literature and would be of benefit to the government and stakeholders towards achieving net zero emissions in the construction industry.

The findings of the study present drivers of carbon reduction and prioritise and categorise them for tailored interventions within the construction sector. Also, it could serve as foundational knowledge for further study in the construction process decarbonisation research area.

The complex interaction of politics and the economy is a critical factor for the sustainable growth and development of the construction sector (CNS). This study aims to investigate the effects of type of political administration including democracy and military on the performance of CNS using the Nigerian Construction Sector (NCS) as a case study.

A 48 year (1970–2017) time series data (TSD) on the NCS and the gross domestic product (GDP) based on 2010 constant USD were extracted from the United Nations Statistical Department database. Analysis of variance (ANOVA) and analysis of covariance (ANCOVA) models were used to analyze the TSD. The ANCOVA model includes the GDP as correlational variable or covariate.

The estimates of the ANOVA model indicate that democratic administration is significantly better than military administration in construction performance. However, the ANCOVA model indicates that the GDP is more important than political administration in the performance of the CNS. The study recommends for a new national construction policy, favourable fiscal and monetary policy, local content development policy and construction credit guaranty scheme for the rapid growth and development of the NCS.

Hitherto, little is known about the influence of political administration on the performance of the CNS. This study provides empirical evidence from a developing economy perspective. It presents the relationships and highlights recommendations for driving growth in the construction industry.

The Land Use Act of 1978 is a promoter of land occupation regardless of gender. However, the marginalisation of women in the occupation of land remains a serious concern. Hence, this study explored the inhibitors to women's right to occupy land in the Ajebamidele Community in Ile-Ife with a view to supporting the need for the proper implementation of land regulations.

The data for the study were elicited from 13 women who were purposively selected. With the aid of Atlas.ti software, the study took a phenomenological approach to the analysis of the data obtained during structured interviews with the respondents.

The results revealed the factors inhibiting women's right to occupy land were unavailability of finance, education status/awareness, intrapersonal factor, custom and tradition, mode of acquisition and socio-economic characteristics.

Like their male counterparts, the role that women play in national development are significant. As such, the findings of this study will assist the government in the formulation of policy for the proper implementation of the current land policies and regulations.

Only a few attempts have been made to study the inhibitors to women's right to occupy land using the qualitative approach in emerging economies.

Brain-drain insurgency has become pervasive amongst professionals and the last option for everyone in the country to realise a sustainable quality of work-life (QWL). All youths now in the country have perceived migrating to the international workspace as a noble idea. This study investigates the incidence of brain-drain and QWL amongst academics in Nigerian universities.

To sparkle a clearer understanding concerning factors preventing the QWL amongst Nigeria's lecturers, this study utilised a cross-sectional research design to survey the participants across all departments in federal institutions through an explanatory research approach. This study applied an array of adapted scales to evaluate members of academic staff track of what provoked the incidence of brain-drain amongst Nigerian lecturers and possible influence on their QWL. The study surveyed 431 members of academic staff in Nigerian universities to collect useful data and employed a structural equation model (SEM) to analyse the obtained data.

The outcome of this study highlights that there is a horrible condition of service amongst Nigerian lecturers, a poor compensation system, poor academic research funding and lack of autonomy are bane to the QWL experienced in Nigerian tertiary institutions today. This study indicates that poor staff development and inadequate university funding are part of the justification that provoked brain-drain insurgence, and allowed the government to lose their skilled and competent egg-heads in the university to other foreign nations of the world.

This study demonstrated that brain-drain has become part of Nigeria's national life given that all professionals are seeking better life where their skills, competence and energy would be valued. Brain-drain was not common until these days amongst academics and fewer studies were noted but this study showed a novel paradigm regarding the QWL and brain-drain trajectory.

Studies on the maturity status of Sub-Saharan African property markets are scanty. The absence of such studies appear to have made African property markets – such as the Nigerian market – unattractive to foreign investors who require market information to assess the viability of proposed investments. The purpose of this paper is to explore the maturity status of selected city property markets in Southwestern Nigeria (i.e. markets in the capital cities of Lagos, Ibadan and Osogbo), with a view to providing information for enhanced property investment in Africa.

The study adopted and expanded on property market maturity paradigms suggested by Keogh and D’Arcy (1994), Akinbogun et al. (2014) and Jones Lang LaSalle (2014) to measure the maturity status of the property markets in the Nigerian cities. The study investigated the maturity of three markets in Nigeria by scoring the stated views of a range of stakeholders (estate surveyors and valuers, public land administrators and financiers represented by commercial banks) across a range of ten indicators. The responses were classified by means of a five-point classification scale which expanded on the initial four-point scale developed by Dugeri (2011).

The three property markets were found to exhibit varying maturity characteristics (with weighted mean scores of 3.07, 2.71 and 2.51, respectively), representing emerging and immature stages of evolution on the maturity path. These results suggest that there is a correlation between the tier of the market and the level of property market maturity.

The study concluded that first- and second-tier city property markets have emerged sufficiently to the point where they may safely attract foreign direct and indirect investment from courageous foreign investors. However, the state governments and real estate professional regulatory bodies in the second and third markets need to undertake substantial remodeling of market structures to make them attractive to international investors.

The value of the paper is in providing much needed information for enhanced property investment in Africa.

This chapter examines the influence of external public borrowing resources on economic progress in Tunisia. The study focuses on two stages: First, the influence is studied in a direct sense and then in an indirect sense, i.e., through a transmission channel of this influence. By applying the autoregressive distributed technique with staggered lags (ARDL), over a period ranging from 1986 to 2019, the results showed that the influence of external borrowing resources on growth seems to be unfavorable in the short term but positive in the long term, hence the importance of the empirical technique chosen. Second, three interaction variables were tested, namely total government expenditure, government investment expenditure, and the real effective exchange rate. The results obtained call for better attention to the channels identified to maximize the positive influence of external public debt on the country's economic progress.

The paper examined the factors influencing the role of estate surveyors in facilities management (FM).

The study administered questionnaires on 247 practicing estate surveyors within Lagos metropolis, Nigeria in 2006. These were selected through alphabetic systematic sampling of estate surveyors from the list of financial members with designations (2004/2005) of the Lagos state branch of Nigerian Institution of Estate Surveyors and Valuers. The survey achieved a total response rate of 85 percent. Statistical tools employed in analyzing data were relative importance indices and factor analysis.

The findings suggest that training in FM and type of business of the organisation managed by the estate surveyor were significant factors that influence surveyors' participation in areas of core competence in FM.

Owing to time constraints, authors have only studied one location. No urban area can be representative of all cities in the country. Nevertheless, the results of the study should at least apply to the majority because most of the estate surveyors in Nigeria are based in Lagos.

The paper introduces an empirical approach to the discussion on role of estate surveyors in FM in Nigeria.