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To convert the post‐production polyethylene terephthalate (PET)‐containing fabrics waste into new value‐added polymeric materials using maleic anhydride grafted linear low‐density polyethylene (LLDPE‐g‐MAH) for improved toughness and to optimise the results of such a modification.

For effective toughening, various blends were made of polyamide 6 (PA) and post‐production PET‐containing fabrics waste (PET) by incorporating different concentrations of maleic anhydride grafted, linear low‐density polyethylene (LLDPE‐g‐MAH). The reactions of LLDPE‐g‐MAH with blend components were studied by Fourier transformation infrared spectroscopy, solubility behaviour of the products in formic acid and rheological measurements. Blends investigated were prepared in a co‐rotating twin‐screw extruder and characterised by differential scanning calorimetry and scanning electron microscopy. The static tensile property and impact strength of the blends were also measured.

The modification of polyamide 6 and post‐production PET‐containing fabrics waste using LLDPE‐g‐MAH showed significant enhancement of impact and interfacial adhesion over the unmodified one. The modification caused a chemical linkage between LLDPE‐g‐MAH and blend components which led not only to forming PA‐co‐LLDPE‐g‐MAH‐co‐PET copolymers, but also to ensuring the intrinsically strong chemical bonds across LLDPE‐g‐MAH phase/PET phase/PA matrix interface, which was the main cause to the improved impact strength and interface adhesion. The optimum results were obtained at 10 per cent of LLDPE‐g‐MAH.

The post‐production PET‐containing fabrics waste used in the present context was defibrated before processing.

The method developed provided a simple and practical solution to recycling and improving the toughness of post‐production PET‐containing fabrics waste.

The method of recycling post‐production PET‐containing fabrics waste was novel and the new polymeric materials obtained could find numerous applications such as hybrid films, fibres and engineering polymers.

A study is performed on the properties of jute-pineapple leaf fiber (PALF) blended yarn and 100% jute yarn. The jute-PALF blend ratios of two counts of yarn (5 and 7 lbs/spy) are 70:30 and 80:20 respectively. The physical properties of the blended yarns such as load at break, strain at break, tenacity at break, tensile modulus and quality ratio are tested and measured. It is observed from the test results that the physical properties of the blended yarns are better than those of the 100% jute yarn. The experimental results also show that the physical and structural properties of the blended yarn changes with the increase of PALF in the blend ratio. So the blending of PALF has a positive impact on yarn properties. Another study is done, in which it is found that surface appearance properties like color strength (K/S value) and whiteness, yellowness and brightness indices of the blended yarns are almost the same as those of the jute yarn due to the blending of jute-PALF. Therefore, the blending ratio does not cause any notable changes in the natural color of the jute yarn.

The purpose of the study is to optimize the blending ratio of Arecanut and cotton fibers to create yarn with the best quality for various applications, particularly home furnishings. The study aims to determine the effect of different blend ratios on the physical and mechanical properties of the yarn.

The study involves blending Arecanut and cotton fibers in various ratios (90:10, 75:25, 50:50, 25:75 and 10:90) at two different yarn counts (10/1 and 5/1). Various physical and mechanical properties of the blended yarn are analyzed, including unevenness, coefficient of mass variation (cvm%), imperfection, hairiness, breaking strength, elongation, tenacity and breaking work.

The research findings suggest that the blend ratio of 10:90 (10% cotton and 90% Arecanut fiber) produced the best results in terms of physical and mechanical properties for both yarn counts. This blend ratio resulted in reduced unevenness, cvm% and imperfection, while also exhibiting good mechanical properties such as breaking strength, elongation, tenacity and breaking work. The blend with a higher concentration of cotton generally showed better properties due to the coarseness of Arecanut fiber. As the goal of the study was to determine the best blend ratio that included the most Arecanut fiber based on its physical and mechanical properties, which is suitable for home furnishing applications, 75:25 Areca cotton blend ratio of yarn count 5/1 proved to be the best.

The study acknowledges that Arecanut fiber must be blended with other commercially used fibers like cotton due to its coarseness. While the study provides insights into optimizing blend ratios for home furnishings and packaging, further research may be needed to make the material suitable for clothing applications.

The research has practical implications for industries interested in utilizing Arecanut and cotton blends for various applications, such as home furnishings and packaging materials. It suggests that specific blend ratios can result in yarn with desirable properties for these purposes.

The study mentions that the increased use of Arecanut fibers can benefit the growers of Arecanut, potentially providing economic opportunities for communities engaged in Arecanut farming.

The research explores the utilization of Arecanut fibers, an underutilized resource, in combination with cotton to create sustainable yarn. It assesses various blend ratios and their impact on yarn properties, contributing to the understanding of eco-friendly textile materials.

In this paper the aim is that Aramid/alginate blended nonwoven fabrics were prepared, and the flame retardancy of the blended nonwoven fabrics was studied by thermogravimetric analysis, vertical flame test, limiting oxygen index (LOI) and cone calorimeter test.

The advantages of different fibers can be combined by blending, and the defects may be remedied. The study investigates whether incorporating alginate fibers into aramid fibers can enhance the flame retardancy and reduce the smoke production of prepared aramid/alginate blended nonwoven fabrics.

Thermogravimetric analysis indicated that alginate fibers could effectively inhibit the combustion performance of aramid fibers at a higher temperature zone, leaving more residual chars for heat isolation. And vertical flame test, LOI and cone calorimeter test testified that the incorporation of alginate fibers improved the flame retardancy and fire behaviors. When the ratio of alginate fibers for aramid/alginate blended nonwoven fabrics reached 80%, the incorporation of alginate fibers could notably decreased peak-heat release rate (54%), total heat release (THR) (29%), peak-smoke production rate (93%) and total smoke production (86%). What is more, the lower smoke production rate and lower THR of the blends vastly reduced the risk of secondary injury in fires.

This study proposes to inhibit the flue gas release of aramid fiber and enhance the flame retardant by mixing with alginate fiber, and proposes that alginate fiber can be used as a biological smoke inhibitor, as well as a flame retardant for aramid fiber.

Increasing scarcity of natural resources and the adverse effects of unsustainable practices call for more and more efficient management strategies in the energy industry. The quality of the coke plays a significant role in the quality and durability of the output steel which is produced using the energy from the coal. This paper aims to investigate the dynamic coal blending problem under overall cost and coke quality constraints in the steel industry within a periodic cycle of operations.

Considering the variability of the natural properties over a periodic cycle, this study proposes a multi-period mixed-integer non-linear programming formulation to optimize the total blending costs while taking various coke quality constraints into account. Besides, this study applies factorial design to investigate about the significant effect of coal proportions as well as improvement into the overall cost of blending.

In this case study, utilizing real data from a coal blending facility in India, through a factorial design, the authors obtain optimal desirable levels of coal proportions and their criticality levels towards the total cost of blending (TCB) or objective function. This analysis reflects the role of the coke quality constraints in the objective function value while characterizing the price of sustainability for the case study among other critical insights.

Objective function (or TCB) includes basic coal cost, movement cost and environmental costs during the coal and coke processing at a coke-oven and blast furnace of steel industry. The price of sustainability provides managerial insights on that sacrifices the industry has to make in order to become more “sustainable”.

The purpose of this paper is to investigate the effect of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and blended formulations on the corrosion inhibition of aluminium in HCl solutions at 30-60°C and to study the mechanism of action.

The inhibitive effect of the homopolymers and polymer blend was assessed using weight loss and hydrogen evolution methods at 30 and 60°C. The morphology of the corroding aluminium surface without and with the additives was visualized using atomic force microscopy. The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.

Results obtained show that inhibition efficiency (η%) increases with increase in concentration of the polymers but decreases with increase in temperature. The inhibition efficiency of the homopolymers and their blends decreased with rise in temperature. Inhibition efficiency was found to be synergistically enhanced on blending the two homopolymers with highest inhibition efficiency obtained for (PEG:PVP) blending ratio of 1:3. The phenomenon of physical adsorption is proposed from the trend of inhibition efficiency with temperature.

The mechanistic aspect of the corrosion inhibition can be better understood using electrochemical studies such as potentiodynamic polarization and electrochemical impedance spectroscopy.

Studies involving the use of polymer blends/mixtures as corrosion inhibitor for metals in corrosive environments are scarce. The results suggest that the mixture could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the use of polymer–polymer mixtures to control acid-induced corrosion of metal.

In this study, researchers applied blended learning program to investigate the success of a blended learning program on satisfaction of the psychological needs, and academic achievement of chemistry students of O-Levels, following curriculum prescribed by University of Cambridge.

Research pattern is quantitative aligned with the quasi-experimental and pre-post experimental design which aimed at examining the efficiency of a motivational strategies adopted with the use of blended learning program on psychological needs satisfaction (competence, autonomy, and relatedness) and achievement in chemistry O-Levels Syllabus, at the end of the research program.

Hypothesis testing represented that use of blended learning program has significant and positive impact on academic achievements through the mediation of autonomy. Results also revealed the substantial association of blended learning on other psychological needs (i.e., competence and relatedness); however, the competence and relatedness have no effect on academic achievements in this study. Thus, research concludes that providing an autonomous environment in substitution of the controlled environment promotes learning and produces positive outcomes.

Blended learning or use of Learning Management Systems is being commonly used mostly in the tertiary level of studies; however, blended learning with secondary classes especially in the field of chemistry is yet not studied in detail. Similarly, the usefulness of the motivational strategies to learn chemistry is observed with university-level students, but very rare data about encouraging students at the secondary level have been gathered. Therefore, the researcher designed this blended learning program to enhance students’ motivation towards achievements in secondary chemistry.

The purpose of this study is to improve the coating properties of shellac–epoxidised novolac blends by treatment with melamine formaldehyde resin (MF) at ambient temperature for its use as a coating material.

Epoxidised-novolac resin was synthesised by epoxidation of novolac resin with epichlorohydrin. Novolac resin was synthesised by reaction of phenol with formaldehyde in acidic medium. Shellac was blended with the epoxidised-novolac resin in solution in varying ratios and treated the blends with MF resin in fixed ratio. Coating properties of the treated compositions were studied using a standard procedure. The compositions were characterised with Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA) and scanning electron microscopic (SEM) spectroscopy.

Treatment of shellac–epoxidised-novolac blends with MF resin improved water and alkali resistance of the blends, besides enhancing gloss. Gloss in all the blends was uniformly increased on treatment with MF resin. Water resistance of the blends tremendously improved after treatment with MF resin. Contact angle of the blends against water increased while decreased against ethylene glycol and dioxane. The compositions were more resistant to polar solvent than non-polar ones, suggesting that the compositions shifted to hydrophobic (lipophilic) nature on treatment with the MF resin.

A specified concentration of MF resin was used in the study. Different concentrations of the MF resin can also be tried for treatment of shellac–epoxidised-novolac blends to see the effect of the resin on the blends.

Treatment of shellac–epoxidised-novolac blend with MF resin improved the coating properties of the blends. The formulation SeNB-64 is the best with high gloss, good impact, scratch hardness and water resistance, and hence can be used as coating material for metal surfaces.

Blending of shellac with epoxidised-novolac resin and treatment of the blends with the MF resin was done for the first time. The formulation SeNB-64 can be used as coating material for metal surfaces.

E-learning is a very popular concept in the education sector today, and one of the best ways to implement this is through blended learning. However, the implementation of blended learning program at Higher Education Institutions (HEIs) is quite new in Bangladesh. The purpose of this paper is to explore the concept of blended learning, how to construct a blended learning program, the benefits of blended learning and some prerequisites to implement blended learning program successfully at HEIs in Bangladesh.

Nature of the study is explanatory, descriptive as well as evaluative. Primary data were collected through face-to-face interviews using structured questionnaire having both open- and close-ended questions including personal observations. Secondary data comprise relevant documents available from government agencies, archives, and library and research organizations.

By utilizing the blended learning tools, HEIs in Bangladesh can achieve radical improvements in education quality as well as in the accessibility and cost-effectiveness of learning programs. Moreover, any innovative educational reform will be successful only when it is fully accepted and adopted by all the key stakeholders: students, parents, teachers, academic administrators, researchers and policy makers.

Several practical solutions have been presented in this paper: how to create a blended learning program, how to overcome the obstacles for successful implementation of blended learning and how to create a flipped classroom with the aid of technology.

A country’s soul and economic well-being depends to a large extent on the quality of their citizen’s education. Implementing innovative teaching programs within the education system will enhance the quality of education at HEIs in Bangladesh, creating more efficient labor force hence benefiting the overall society.

Originality in terms of exposing the hurdles that needs to be addressed for successful implementation of blended learning programs at HEIs in Bangladesh and providing an easy guideline to educators on how to create flipped classrooms.

The purpose of the present research is to examine the role and influence of modern method of blended learning in the formation and development of professional competencies on the example of the faculty members of Al Ain University from the viewpoint of its students and determine the relevance of the educational method of blended learning in modern society and science according to world situation.

The study sample consisted of 980 male and female students in the second semester of 2019–2020. The comparative analysis of the influence of blended learning on the knowledge level and improvement of professional competencies among students of two faculties was taken into account.

The results of the survey according to chosen criteria showed that the professional competencies required for the faculty members were moderate. According to the results of the survey, most of respondents (75%) are sure that the level of blended learning at their educational institution is high. 35% of respondents think that blended learning helps to develop technological competency as well as self-development (25%), motivation (18%), critical thinking (12%), self-discipline and time management (10%).

The relevance of problematic issue of blended learning is determined by the new conditions of educational process connected with pandemic. The prospects for further research can be based on the results of this study especially the relevance is connected with the study of the experience of using modern method of blended learning in different foreign countries on the basis of surveys and developed programs.