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The purpose of this study is to advance the application of pulverised cow bone ash (PCBA) as a partial replacement of cement in soil stabilisation for the production of bricks. The study investigated the impact of PCBA substitution on the characteristic strength of clay bricks under variant curing media.

Dried cow bones were pulverised, and an energy-dispersive X-ray fluorescence test was conducted on PCBA samples to determine the chemical constituents and ascertain the pozzolanic characteristics. Ordinary Portland cement (OPC) and PCBA were blended at 100%, 75%, 50%, 25% and 0% of cement substitution by mass to stabilise lateritic clay at 10% total binder content for the production of bricks. The binder-to-lateritic clay matrixes were used to produce clay bricks and cylinders for compressive and splitting tensile strength tests, respectively.

The study found that PCBA and OPC have similar chemical compositions. The strength of the clay bricks increased with curing age, and the thermal curing of clay bricks positively impacted the strength development. The study established that PCBA is a suitable substitute for cement, up to 25% for stabilisation in clay brick production.

Construction stakeholders can successfully use a PCBA-OPC binder blend of 1:3 to stabilise clay at 10% total binder content for the production of bricks. The stabilised clay bricks should be cured at an elevated temperature of approximately 90°C for 48 h to achieve satisfactory performance.

The PCBA-OPC binder blend provides adequate soil stabilisation for the production of clay bricks and curing the clay bricks at elevated temperature. This aspect of the biomass/OPC binder blend has not been explored for brick production, and this is important for the reduction of the environmental impacts of cement production and waste from abattoirs.

This paper aims to control the clay’s dispersion within the PA6 matrix. Cloisite Na+, a naturally occurring sodium montmorillonite (NaMMT), and Cloisite 30B and 93A, two organophilic MMT (OMMT), were used for this purpose.

By using a twin-screw extruder for melt mixing, Polyamide 6 (PA6)/NaMMT nanocomposites with 1, 3, 5 and 10 Wt.% Cloisite Na+ and PA with 5 and 10 Wt.% Cloisite 30B and 93A were created. PA6/OMMT nanocomposite to investigate how organoclay disperses within the PA6.

The link among PA6 and the silicate layer was evaluated via (FTIR), confirming presence of a compact contact between the nanosilicate layer and PA6 segments. Thermal behavior of obtained nanocomposites was evaluated through a thermogravimetric analyzer. The data confirmed that the thermal behavior of PA6 was moderately improved once addition 5 Wt.% filler, in the order: Cloisite Na+>Cloisit 93A>Cloisit 30B.Electrical properties have been studied through measuring dielectric constant, dielectric loss and conductivity measurment that procced at frequencies from 10^–1 to 107 Hz and temperatures from 40°C to 120°C, dielectric constant (έ) and dielectric loss (έ) of the nanocomposite were sharply increased with increasing the two parameters temperature and frequency.

The hybrid nanomaterials of PA6/ Cloisite Na+, Cloisite 93A or Cloisite 30B can be credited as electronic nanodevices and microwave semiconductors materials with a small amount of nanoclay filler as illustrated in the conclusion.

At the end of the case discussion, students should be able to trace the journey of launching a start-up by evaluating how opportunities and hurdles can be navigated throughout the international entrepreneurial process; assess the increasing trend towards internationalisation for start-ups and identify a range of factors contributing to the growth in global entrepreneurship; formulate an argument highlighting the role of the networking and partnerships when adopting a global strategy; propose how a firm could develop a unique mix of resources to obtain a sustained competitive advantage globally against other firms; and make an informed decision regarding various issues that entrepreneurs need to consider when going global and analyse how they can effectively deal with a crisis they may face.

Oryx Desert Salt is sourced from ancient, unpolluted, sustainable underground salt lakes in the pristine and remote uninhabitable Kalahari semi-desert of South Africa. Samantha Skyring is the founding CEO of Oryx Desert Salt. Her inspiration for the name was her 120-km, one-week walk through the Namib Desert in 2000, when she had several close encounters with the Oryx Gazelle, becoming the symbol of that Kalahari experience. Oryx products currently feature on the tables of between 1,500 and 2,500 local restaurants country-wide, and in the retail sector, Oryx salt is on the shelves of about 1,000 stores of retailers, plus in several health shops and deli’s countrywide. Regarding the business’s global footprint, Oryx Desert Salt currently exports to 23 countries and is also available on Amazon.com. Notwithstanding that Samantha Skyring has succeeded in making Oryx Desert Salt the well-known local household brand she had intended; she is contemplating greater international expansion and reach. She has envisioned Oryx salt to become a respected global household brand, in the same way Himalayan pink salt gained popularity worldwide as a gourmet salt. Given Samantha’s challenge of finding suitable speciality distributors in the different countries to help get her product in restaurants and retail, what would be the best approach to achieve her vision of becoming a global brand? To what extent could she capitalise and leverage various resources to further globalise Oryx’s business operations? How could she ensure that the extent and diversity of global reach provides Oryx Desert Salt with a sustained competitive advantage?

Master of Business Administration (MBA), Master of Management, Executive Education

Teaching notes are available for educators only.

CSS 3: Entrepreneurship.

The aim of the current study is to inspect the influence of high temperatures on the compressive and split-tensile-strength (STS) of concrete mixtures produced by replacing natural river sand with waste-foundry sand (WFS) at 25%, 50%, 75% and 100%. When the experimental findings and the projected outcomes were compared by IS:456-2000 code equations, the STS results predicted by the suggested mathematical equations exhibit lower variations. It is proposed to employ the presented mathematical formulas to evaluate the STS of concrete cylindrical specimens at higher temperatures.

After fabricating, concrete mixtures were allowed to cure for 28 days. For the purpose of avoiding explosive spalling during the heating process, concrete samples are taken out from the curing chamber after 28 days and allowed to dry for two days. The manufactured concrete specimen is exposed to 100 °C, 200 °C, 300 °C, 400 °C, 500 °C and 600 °C temperatures for a duration of 2 h. After the specimens have cool down to room temperature (RT), the physical test, ultrasonic-pulse-velocity (UPV) test, compressive strength test and STS test are carried out.

With an increase in WFS content, concrete specimens' residue compressive-strength and STS decreases. The STS of samples declines as the WFS content rises with increase in temperature interval. According to the UPV test, the concrete samples quality is “good” up to 400 °C; after 500 °C, it ranges from “doubtful to poor.” The UPV values of various mixes declined as the temperature increased. Mass losses increase with exposure to greater temperatures and with an increase in the proportions of WFS in concrete specimens. For mixtures MWFS-0, MWFS-1, MWFS-2, MWFS-3 and MWFS-4 (0%, 25%, 50%, 75% and 100% WFS content), no cracks were present on any of the samples below 400 °C. Concrete surfaces start to show cracks whenever the intervals of temperature increase above 400 °C.

In this investigation, WFS elements are totally substituted for natural sand in concrete mixtures. The residue strength properties, including residual compressive strength and residual STS, were found to be lower after exposures to greater temperature when comparisons were made to referral mixtures. When comparing specimens’ compressive strength, higher temperatures have more effects on the STS of samples with higher WFS contents.

Pigments, as essential colorants, are extensively used in industries such as coatings, inks and plastics. However, the dispersibility of pigments during application critically affects their performance. Therefore, it is crucial to enhance pigment dispersion to improve their application performance. This paper aims to offer valuable insights into the enhancement of pigment dispersion.

Drawing upon existing research on pigment dispersion, this study synthesizes key achievements into two main categories: pigment dispersion mechanism and pigment dispersion technology.

Concerning pigment dispersion mechanism, the article summarizes the three pivotal processes and their respective mechanisms: wetting, dispersion and stabilization. In addition, research advances in computational modeling and structure–activity relationship studies are introduced. Regarding pigment dispersion technology, the paper reviews technological advancements in the utilization of surfactants, solid solution preparation, application of potential pigments, manufacture of pigment derivatives and encapsulation of polymer materials.

Understanding the dispersion mechanism and dispersion technology is instrumental in guiding pigment dispersion practices. Effective application of these principles can enhance pigment performance and expand their application scope.

Everyone is extremely concerned about environmental protection and health safety due to the rise in living standards. Plant-derived natural dyes have garnered much industrial attention in food, pharmaceutical, textile, cosmetics, etc. owing to their health and environmental benefits. The present study aims to focus on the elimination of the use of synthetic dyes and provides brief information about natural dyes, their sources, extraction procedures with characterization and various advantages and disadvantages.

In producing natural colors, extraction and purification are essential steps. Various conventional methods used till date have a low yield, as these consume a lot of solvent volume, time, labor and energy or may destroy the coloring behavior of the actual molecules. The establishment of proper characterization and certification protocols for natural dyes would improve the yielding of natural dyes and benefit both producers and users.

However, scientists have found modern extraction methods to obtain maximum color yield. They are also modifying the fabric surface to appraise its uptake behavior of color. Various extraction techniques such as solvent, aqueous, enzymatic and fermentation and extraction with microwave or ultrasonic energy, supercritical fluid extraction and alkaline or acid extraction are currently available for these natural dyes and are summarized in the present review article.

If natural dye availability can be increased by the different extraction measures and the cost of purified dyes can be brought down with a proper certification mechanism, there is a wide scope for the adoption of these dyes by small-scale dyeing units.

The manufacture of polymer composites with a lower environmental footprint requires incorporation of sustainably sourced components. In addition, the incorporation of novel components should not compromise the material properties. The purpose of this paper is to demonstrate the use of a synthetic amine functional toluidine acetaldehyde condensate (AFTAC) as a modifier for fiber-reinforced epoxy composites. One of the fiber components was sourced from agricultural byproducts, and glass fiber was used as the fiber component for comparison.

The AFTAC condensate was synthesized via an acid-catalyzed reaction between o-toluidine and acetaldehyde. To demonstrate its efficacy as a toughening agent for diglycidyl ether bisphenol A resin composites and for the comparison of reinforcing materials of interest, composites were fabricated using a natural fiber (mat stick) and a synthetic glass fiber as the reinforcing material. A matched metal die technique was used to fabricate the composites. Composites were prepared and their mechanical and thermal properties were evaluated.

The inclusion of AFTAC led to an improvement in the mechanical strengths of these composites without any significant deterioration of the thermal stability. It was also observed that the fracture strengths for mat stick fiber-reinforced composites were lower than that of glass fiber-reinforced composites.

To the best of the authors’ knowledge, the use of the AFTAC modifier as well as incorporation of mat stick fibers in epoxy composites has not been demonstrated previously.

This study explores the contributions of fly ash, bottom ash and biomass ash from coal and biomass power plants for enhancing circular economy of construction sectors in emerging economies.

This research investigates their applications in construction, emphasizing their role in reducing environmental impact and promoting circular economy principles. Through a qualitative analysis using data from structured interviews with 41 involved stakeholders, the study highlights the economic and environmental benefits of integrating these by-products into business operations.

Currently, the cement and concrete industries can successfully adopt almost 100% fly ash, but logistic optimization is necessary to address the wet fly ash problem. The practical applications of bottom ash pose disposal challenges due to their poor adoption. Biomass ash can be alternatively implemented as a soil amendment and fertilization in the agriculture industry while current growth seems significant with the shift to a clean energy policy.

This research underscores the importance of policy support and collaboration between industry stakeholders to maximize the sustainable potential of these by-products in an emerging economy context.

The sustainability development goals (SDGs) were well-established in developing economies. Nevertheless, the literature review indicates that there is a lack of understanding regarding their backgrounds, influencing factors, challenges and practical applications for the circular economy.

This paper aims to identify modern construction techniques for affordable housing, such as prefabrication and interlocking systems, that can save time and cost while also providing long-term sustainable benefits that are desperately needed in today's construction industry.

The need for housing is growing worldwide, but traditional construction cannot cater to the demand due to insufficient time. There should be some paradigm shift in the construction industry to supply housing to society. This paper presented a state-of-the-art review of modern construction techniques practiced worldwide and their advantages in affordable housing construction by conducting a systematic literature review and applying the backward snowball technique. The paper reviews modern prefabrication techniques and interlocking systems such as modular construction, formwork systems, light gauge steel/cold form steel construction and sandwich panel construction, which have been globally well practiced. It was understood from the overview that modular construction, including modular steel construction and precast concrete construction, could reduce time and costs efficiently. Further enhancement in the quality was also noticed. Besides, it was observed that light gauge steel construction is a modern phase of steel that eases construction execution efficiently. Modern formwork systems such as Mivan (Aluminium Formwork) have been reported for their minimum construction time, which leads to faster construction than traditional formwork. However, the cost is subjected to the repetitions of the formwork. An interlocking system is an innovative approach to construction that uses bricks made of sustainable materials such as earth that conserve time and cost.

The study finds that the prefabrication techniques and interlocking system have a lot of unique attributes that can enable the modern construction sector to flourish. The study summarizes modern construction techniques that can save time and cost, enhancing the sustainability of construction practices, which is the need of the Indian construction industry in particular.

This study is limited to identifying specific modern construction techniques for time and cost savings, lean concepts and sustainability which are being practiced worldwide.

Modern formwork systems such as Mivan (Aluminium Formwork) have been reported for their minimum construction time which leads to faster construction than traditional formwork.

The need for housing is growing rapidly all over the world, but traditional construction cannot cater to the need due to insufficient time. There should be some paradigm shift in the construction industry to supply housing to society.

This study is unique in identifying specific modern construction techniques for time and cost savings, lean concepts and sustainability which are being practiced worldwide.

The purpose of this article is to assess climate change impacts on four earthen heritage (EH) sites, highlighting their vulnerability and the need for an integrated approach that considers physical, social and cultural factors.

The study uses a systematic approach to assess climate change impacts on earthen heritage sites. A literature review informed the development of a conceptual model based on climate change risk guidelines and methodologies. The model evaluates site-specific hazards through quantitative and qualitative assessments, considering exposure, sensitivity and adaptive capacity. Vulnerability is calculated using a formula that categorizes it into five levels. Data collection included meteorological analysis, field observations and interviews with local experts.

Findings indicate that climate change has significant consequences for earthen heritage sites, including erosion, structural deterioration and loss of cultural value. The regions of Sistan, Yazd, Persepolis and Tchogha Zanbil are particularly vulnerable due to their specific climatic conditions. Key threats include changes in precipitation patterns, extreme weather events, rising temperatures and water scarcity. Socioeconomic factors like limited conservation resources and inadequate stakeholder communication exacerbate these vulnerabilities. The study highlights the need for interdisciplinary collaboration, effective governance and community engagement to develop comprehensive climate change adaptation strategies.

The article’s originality lies in its systematic assessment of climate change impacts on earthen heritage sites, offering a novel framework that integrates interdisciplinary approaches and site-specific factors.