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This paper aims to assess the suitability of cement combination containing CEM I, fly ash, silica fume and metakaolin for durability design against carbonation-induced corrosion in concrete.

Cube compressive strengths at 28 days and accelerated carbonation depths at 28 days and at various exposure ages were determined at the water/cement ratios of 0.35, 0.50 and 0.65. To assess their suitability for carbonation-induced corrosion, the material costs and embodied carbon dioxide (eCO₂) contents of the concretes at equivalent performance were compared.

Cement combination concretes achieved equal carbonation resistance with CEM I at higher compressive strengths, lower water/cement ratios and higher cement contents. The comparison of the concretes, at equivalent performance, based on the carbonation-induced corrosion exposure classes XC3 and XC4 (Table A.4 of BS 8500-1), shows that ternary and more binary cement concretes have lower costs and eCO₂ contents than those recommended in Table A.6 of BS 8500-1.

This analysis is limited to a working life of 50 years. Further research is needed to verify the suitability of the cement combinations for a working life of 100 years and for the other aspects of durability design covered in BS 8500.

Cement combination concretes have lower eCO₂ content. Hence, when they are cheaper than CEM I concrete at equivalent performance, they would make concrete construction more economic and environmentally compatible.

This research suggests the inclusion of metakaolin and ternary cement combination concretes in BS 8500 for durability design against carbonation-induced corrosion.

The purpose of this study is to explore the feasibility of utilizing agricultural (almond shell, rice husk and wood) waste biochars for partial cement replacement by evaluating the relationships between the physiochemical properties of biochars and the early-age characteristics of cement pastes.

Biochars are prepared through the thermal decomposition of biomass in an inert atmosphere. Using varying percentages, biochars are used to replace ordinary Portland cement (OPC) in cement pastes at a water/binder ratio of 0.35. Characterization methods include XPS, FTIR, SEM, TGA, BET, Raman, loss-on-ignition, setting, compression and water absorption tests.

Accelerated setting in biochar-modified cement pastes is attributed to chemical interactions between surface functional groups of biochars and calcium cations from OPC, leading to the early development of metal carboxylate and alkyne salts, alongside the typical calcium-silicate-hydrate (C-S-H). Also, metal chlorides such as calcium chlorides in biochars contribute to the accelerate setting in pastes. Lower compression strength and higher water absorption result from weakened microstructure due to poor C-S-H development as the high carbon content in biochars reduces water available for optimum C-S-H hydration. Amorphous silica contributes to strength development in pastes through pozzolanic interactions. With its optimal physiochemical properties, rice-husk biochars are best suited for cement replacement.

While biochar parent material properties have an impact on biochar properties, these are not investigated in this study. Additional investigations will be conducted in the future.

Carbon/silicon ratio, oxygen/carbon ratio, alkali and alkaline metal content, chlorine content, carboxylic and alkyne surface functional groups and surface areas of biochars may be used to estimate biochar suitability for cement replacement. Biochars with chlorides and reactive functional groups such as C=C and COOH demonstrate potential for concrete accelerator applications. Such applications will speed up the construction of concrete structures and reduce overall construction time and related costs.

Reductions in OPC production and agricultural waste deterioration will slow down the progression of negative environmental and human health impacts. Also, agricultural, manufacturing and construction employment opportunities will improve the quality of life in agricultural communities.

Empirical findings advance research and practice toward optimum utilization of biomass in cement-based materials.

This study aims to examine the housing outcomes of natives and multiple generations of non-natives using a longitudinal survey data in Britain.

The authors use longitudinal data from Britain, in which they can observe multiple generations of immigrants and their demographic and economic information.

The probability models for housing tenure reveal significant variation in the outcomes which are robust to several econometric specifications.

As migration and its impact on local economy is a highly debated topic across several major regions of the world, the findings bring out important insights with policy implications. The research is limited by the sample size of the longitudinal survey.

The empirical evidence on the topic is quite limited with mixed findings. Especially, the authors’ ability to look through multiple generations is unique in identifying the variation in housing outcomes for the native and non-native citizens.

The purpose of this paper is to discuss the durability and flexibility characteristics of latex modified ferrocement in comparison with conventional ferrocement particularly when exposed to severe environmental conditions.

The research programme encompasses the laboratory investigation on the structural, the deformation behaviour and characteristic of latex modified ferrocement elements cured in air and salt‐water environments. The tests include determination of load and deflection characteristics, moments, crack widths, crack spacing, and the number of cracks when subjected to static flexure.

Test result indicates a significant improvement in reducing and bridging micro cracks, especially in the pre‐peak load region. Fracture toughness and deformability increased significantly. However, the post peak behaviour was quite similar to conventional ferrocement.

The results show that latex modification has improved the mechanical properties of cement mortars, particularly their flexural strength.

Recycled fibres used as reinforcements are obtained from garment cut wastes of cotton, polyester and cotton/polyester fabrics to develop these composites. These composites are developed by using Epoxy resin, Kaolinite, Polypropylene sheet as matrices. Reinforcements and matrices have been used in different compositions and combinations to develop these composites. The main advantages of this type of composites are to combine the different properties of different materials to obtain unique and high-performance material.

Garment cut wastes from apparel industries are used for various applications in various industries. Normally, garment cut wastes and recycled fibres from garment cut wastes are used in textile, furniture, carpet, paper, automobile, construction and agricultural industries in low mechanical performance applications. In this research, composites are developed by using recycled fibres obtained from garment cut wastes as reinforcement and with different types of matrices.

Technical properties like thickness, mass per unit area, Tensile strength, Flexural strength, Impact strength, Water absorbency and Scanning Electron Microscope of developed composites were tested and analyzed. The outcome of the results demonstrates that many of the composite proportions with different blend, reinforcement and matrcies show superior mechanical performances when compared with each other, and it can be recommended for many potential applications.

The properties of composites are dependent on the different blend proportions of recycled fibres with reinforcement and matrices. Based on the result of tensile strength, polyester/cotton fibre reinforced composites show superior strength compared to other recycled fibre reinforced samples and it can be suitably tailored further by appropriate design of different lay-up angle and orientation with the number of different preformed layers of reinforcements to suit the intended applications.

This paper examines the link between parental income during adolescent years and higher education choices of the offspring at age 18. This study is the first to use a recent longitudinal data set from New Zealand (Christchurch Health and Development Surveys, CHDS), in the higher education context. The paper examines the impact of family income and other resources throughout adolescent years on later decisions to participate in higher education and the choice of type of tertiary education at age 18. A binary choice model of participation in education, and a multinomial choice model of the broader set of choices faced at age 18, of employment, university, or polytechnic participation are estimated. Among the features of the study are that it incorporates a number of variables, from birth to age 18, which allow us to control further than most earlier studies for ability heterogeneity, academic performance in secondary school, in addition to parental resources (e.g. childhood IQ, nationally comparable high school academic performance, peer effects, family size and family financial information over time). The results highlight useful features of intergenerational participation in higher education, and the effect of parental income on university education, in particular.

This study aims to analyze the individual and joint effects of institutional support by government and nongovernment institutions on early internationalizing firms’ (EIFs) performance. It also investigated the moderating impact of firm age and size on the institutional support-firms’ export performance relationships.

Data were collected from 705 EIFs in the apparel industry of Bangladesh and analyzed with hierarchical regression.

The positive influence of institutional support on exporting firms’ financial performance is stronger for the joint effect of government and nongovernment assistance than the individual impact. Firms’ size positively moderates the impact of individual government and nongovernment assistance, while age positively moderates their resource-bundling effect.

The findings suggest the necessity of integrating resources from diverse but complementary sources of institutional support for superior export performance. The findings also show the presence of the liability of smallness and liability of newness in the standalone and joint influence of institutional support, respectively.

Firms need to bundle resources obtained from the government (unrequited) and nongovernment (reciprocal) institutional support to overcome the liability of smallness they might encounter while availing of support from only one source.

Distinguishing between government and nongovernment institutional support, this paper sheds light on exporting firms’ resource-bundling mechanism for these two sources of support in the backdrop of an emerging economy. It also offers fresh insights into the critical role of the liabilities of newness and smallness in early internationalization, especially with regard to the home-country institutional environment.

The dual forces of an increasing dependency ratio and lower labor market participation on the part of mature individuals does not bode well for the American and European Communities. To begin to better understand such macro influences, changing demographic trends in the U.S. and European community with regard to the aging population and workforce participation are reviewed. In addition, recent research which continues to dispel the myth of a negative relationship between age and job performance is reviewed. A more informative way of looking at possible relationships between age and job performance is presented. A variety of contingent work arrangements and flexible employment policies are reviewed as a potential solution to the decreased supply of skilled labor for employers and the need for continued income and community involvement on the part of mature individuals. In addition, a call for a redefinition of how we currently view retirement is sounded. We conclude with recommendations for both employers and mature individuals on dealing with the issues presented.

The purpose of this study is to examine the impact of chief executive officer (CEO) personal characteristics on the performance of Indian commercial banks. Additionally, it also analyses the nonlinear relationship of CEO age and CEO tenure on the bank performance.

A balanced panel data approach has been used in this study. Particularly, the fixed effect estimation technique is used to examine the relationship between CEO characteristics and bank performance during the period 2009–2010 to 2016–2017.

The authors find that professional qualification of CEOs in finance stream enhances performance. Additionally, the impact of CEO duality is found to be positive and significant on performance. Male CEOs are beneficial for bank performance. Well experienced CEOs contribute to higher performance. The results are robust across the various proxies of bank performance, and sub-samples based on ownership, size of the bank and board size.

This study provides insights to policy regulators and policymakers who are entrusted with the appointment of the CEOs in the banks in the light of the ongoing regulatory reforms.

This study can be considered as one of the early studies, which examines the association between CEO characteristics and bank performance from an emerging economy perspective. It also extends the existing study by considering both public and private banks operating in India.

The purpose of this paper is to investigate the determinants of mobile banking (m-banking) for individual performance and whether or not there are any age or gender differences.

The research model is based on the task-technology fit (TTF) theory, which integrates elements of task and technology characteristics, technology usage, and individual performance, while combining the age and gender subsamples. The empirical approach was based on an online survey questionnaire of 256 individuals. Partial least squares based on the multi-group analysis were used to analyse the proposed framework construct relationships.

The results reveal that TTF and usage are important precedents of individual performance. The authors find statistically significant differences in path usage to performance impact for the age subsample, and no statistically significant differences for the gender subsample.

The paper highlights the TTF model to understand the determinants that influence the individual performance of m-banking, and whether or not there are any age or gender differences. While most earlier research focuses on m-banking adoption, the approach diverges from the majority of the work by examining the individual performance, which has not been considered in earlier studies.