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Article
Publication date: 3 March 2020

Yacine Abadou, Abderrahmane Ghrieb, Rosa Bustamante and Hayette Faid

The purpose of this study is to fit an appropriate mathematical model to express response variables as functions of the proportions of the mixture components. One purpose of…

Abstract

Purpose

The purpose of this study is to fit an appropriate mathematical model to express response variables as functions of the proportions of the mixture components. One purpose of statistical modeling in a mixture experiment is to model the blending surface such that predictions of the response for any mixture component, singly or in combination, can be made empirically. Testing of the model adequacy will also be an important part of the statistical procedure.

Design/methodology/approach

A series of mortar using air lime, marble and ceramic sanitary waste aggregates were prepared for statistically designed combinations. The combinations were designed based on the mixture-design concept of design of experiments; this mortar is often used as a filler material in restoration projects. The aim of this work is to find an optimal composition of a paste for the manufacture of air lime mortar with ceramic and marble waste. This investigation aims to recommend mix design for air lime-based mortar, by optimizing the input combination for different properties, and to predict properties such as mechanical strength, thermogravimetric and x-ray diffraction analysis with a high degree of accuracy, based on a statistical analysis of experimental data.

Findings

This paper discusses those mortar properties that architects, contractors and owners consider important. For each of these properties, the influence of ceramic and marble waste in the air lime mortar is explored. The flexibility of lime-based mortars with waste materials to meet a wide range of needs in both new construction and restoration of masonry projects is demonstrated.

Originality/value

The objective of the present investigation is to recommend mixture design for air lime mortar with waste, by optimizing the input combination for different properties, and to predict properties such as compressive strength, flexural strength with a high degree of accuracy, based on the statistical analysis of experimental data. The authors conducted a mixture design study that takes into account dependent parameters such as the constituents of our air lime-based mortar where we have determined an experiment matrix to which we have connected the two responses, namely, compressive and flexural strength. By introducing the desirability criteria of these two responses, using JMP software, we were able to obtain a mixture optimal for air lime mortar with ceramic and marble waste.

Details

Journal of Engineering, Design and Technology , vol. 18 no. 6
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 17 April 2009

George J. Besseris

The aim of this paper is to examine product formulation screening at the industrial level in terms of multi‐trait improvement by considering several pertinent controlling factors.

Abstract

Purpose

The aim of this paper is to examine product formulation screening at the industrial level in terms of multi‐trait improvement by considering several pertinent controlling factors.

Design/methodology/approach

The study adopts Taguchi's orthogonal arrays (OAs) for sufficient and economical sampling in a mixture problem. Robustness of testing data is instilled in this method by employing a two‐stage analysis where controlling components are investigated together while the slack variable is tested independently. Multi‐responses collapse to a single master response has been incurred according to the Super Ranking concept. Order statistics are employed to provide statistical significance. The slack variable influence is tested by regression and nonparametric correlation.

Findings

Synergy among Taguchi methodology, super ranking and nonparametric testing was seamless to offer practical resolution to product component activeness. The concurrent modulation of two key product traits due to five constituents in the industrial production of muffin‐cake is invoked. The slack variable, rich cream, is strongly active while the influence of added amount of water is barely evident.

Research limitations/implications

The method presented is suitable only for situations where industrial mixtures are investigated. The case study demonstrates prediction capabilities up to quadratic effects for five nominated effects. However, the statistical processor selected here may be adapted to any number of factor settings dictated by the OA sampling plan.

Practical implications

By using a case study from food engineering, the industrial production of a muffin‐cake is examined focusing on a total of five controlling mixture components and two responses. This demonstration emphasizes the dramatic savings in time and effort that are gained by the proposed method due to reduction of experimental effort while gaining on analysis robustness.

Originality/value

This work interconnects Taguchi methodology with powerful nonparametric tests of Kruskal‐Wallis for the difficult problem of non‐linear analysis of mixtures for saturated, unreplicated fractional factorial designs in search of multi‐factor activeness in multi‐response cases employing simple and practical tools.

Details

International Journal of Quality & Reliability Management, vol. 26 no. 4
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 26 September 2008

Yagoub Mansoori and Firdovsi Tataroglu Seyidov

The aim of this paper is to focus on the production of mixed‐synthetic diester base oils from the waste of electrochemical production of sebacic acid (mixtures of methyl esters of…

1573

Abstract

Purpose

The aim of this paper is to focus on the production of mixed‐synthetic diester base oils from the waste of electrochemical production of sebacic acid (mixtures of methyl esters of dicarboxylic acids, HOOC(CH2)nCOOH, n=4, 6, 8).

Design/methodology/approach

The mixtures of methyl esters of dicarboxylic acids ((CH2)n, n=4, 6, 8) are transesterified by pure alcohols and also different mixtures of aliphatic monohydric alcohols, C6‐C10 of iso‐ and normal structure, in the presence of a new catalyst system (tetra‐n‐butyl orthotitanate, Ti(O‐n‐Bu)4). The effects of starting materials ratios on the reaction progress and characteristic features of the obtained diester oils have been studied.

Findings

The obtained mixed diester oils showed similar thermal properties and low pour point (minimum −70°C), and improved viscosity‐temperature properties compared with commercially available dioctyl sebacate (DOS) and dioctyl adipate (DOA) diester oils.

Research limitations/implications

Because of the complexity of the obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

Practical implications

The mixtures of methyl esters of dicarboxylic acids obtained from different batches of sebacic acid production have different molar ratios and must be analyzed before use. The process is based on transesterification reactions of methyl esters of mixture of the aliphatic dicarboxylic acids ((CH2)n, n=4, 6, 8) by mixture of aliphatic alcohols having iso‐ and normal structure in the presence of a new transesterification catalyst (mixture of p‐toluene sulfonic acid and tetra‐n‐butyl orthotitanate). The obtained mixed diester oils showed similar thermal properties, low pour point (minimum −70°C) and improved viscosity‐temperature properties compared with commercially available DOS and DOA diester oils.

Originality/value

The paper illustrates a new process for the production of mixed‐synthetic diester base oils.

Details

Industrial Lubrication and Tribology, vol. 60 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 27 October 2020

Pavana Kumara Bellairu, Shreeranga Bhat and E.V. Gijo

The aim of this article is to demonstrate the development of environment friendly, low cost natural fibre composites by robust engineering approach. More specifically, the prime…

Abstract

Purpose

The aim of this article is to demonstrate the development of environment friendly, low cost natural fibre composites by robust engineering approach. More specifically, the prime objective of the study is to optimise the composition of natural fibre reinforced polymer nanocomposites using a robust statistical approach.

Design/methodology/approach

In this research, the material is prepared using multi-walled carbon nanotubes (MWCNT), Cantala fibres and Epoxy Resin in accordance with the ASTM (American Society for Testing and Materials) standards. Further, the composition is prepared and optimised using the mixture-design approach for the flexural strength of the material.

Findings

The results of the study indicate that MWCNT plays a vital role in increasing the flexural strength of the composite. Moreover, it is observed that interactions between second order and third order parameters in the composition are statistically significant. This leads to proposing a special cubic model for the novel composite material with residual analysis. Moreover, the methodology assists in optimising the mixture component values to maximise the flexural strength of the novel composite material.

Originality/value

This article attempts to include both MWCNT and Cantala fibres to develop a novel composite material. In addition, it employs the mixture-design technique to optimise the composition and predict the model of the study in a step-by-step manner, which will act as a guideline for academicians and practitioners to optimise the material composition with specific reference to natural fibre reinforced nanocomposites.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 3 November 2021

M. Poornesh, Shreeranga Bhat, E.V. Gijo and Pavana Kumara Bellairu

This article aims to study the tensile properties of a functionally graded composite structure with Al–18wt%Si alloy as the matrix material and silicon carbide (SiC) particles as…

Abstract

Purpose

This article aims to study the tensile properties of a functionally graded composite structure with Al–18wt%Si alloy as the matrix material and silicon carbide (SiC) particles as the reinforcing element. More specifically, the study's primary objective is to optimize the composition of the material elements using a robust statistical approach.

Design/methodology/approach

In this research, the composite material is fabricated using a combination of stir casting and the centrifugal casting technique. Moreover, the test specimen required to study the tensile strength are prepared according to the ASTM (American Society for Testing and Materials) standards. Eventually, optimal composition to maximize the tensile property of the material is determined using the mixture design approach.

Findings

The investigation results imply that the addition of the SiC plays a crucial role in increasing the tensile strength of the composite. The optical microstructural images of the composite show the adequate distribution of the reinforcing particles with the matrix. The proposed regression model shows better predictability of tensile strength. In addition, the methodology aids in optimizing the mixture component values to maximize the tensile strength of the produced functionally graded composite structure.

Originality/value

Little work has been reported so far where a hypereutectic Al–Si alloy is considered the matrix material to produce the composite structure. The article attempts to make a composite structure by using a combination of stir casting and centrifugal casting. Furthermore, it employs the mixture design to optimize the composition and predict the model of the study, which is one of a kind in the field of material science.

Abstract

Purpose

The purpose of this paper is to optimize a mixed juice made from Brazilian Cerrado fruits (cagaita, mangaba and marolo).

Design/methodology/approach

The juices were evaluated by rheological, physical, physicochemical, nutritional and sensory acceptance analyses. The mixture design is a widely used tool for product optimization, allowing the determination of factors, combinations and levels that provide best responses.

Findings

The results show that using mangaba pulp negatively contributed to juice acceptance, but resulted in the highest ascorbic acid content. The treatments produced using cagaita and marolo pulps presented a greater acceptance by consumers, and contributed to higher antioxidant activity and phenolic compounds content. The juice prepared with a mixture of equivalent quantities of the three fruits had the highest β-carotene and lycopene contents.

Practical implications

This research has shown that different fruit combinations can improve sensory and nutritional characteristics, adding value to the final product.

Social implications

The processing of mixed juices could increase population access to the nutrients present in Brazilian Cerrado fruits, given that they are seasonal and perishable fruits.

Originality/value

In recent years, there has been an increase in the development of new food products based on Cerrado native fruits, however information on the chemical and nutritional characteristics, rheological behavior, and sensory attributes of the derivative products are still limited, resulting in a lack of scientific investments in this area. In addition, it is necessary to optimize the developed products to offer the consumer a unique product, combining the characteristics of two or more fruits, which adds value to the final product.

Details

British Food Journal, vol. 120 no. 10
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 20 September 2021

Jared Allison, John Pearce, Joseph Beaman and Carolyn Seepersad

Additive manufacturing (AM) of thermoplastic polymers for powder bed fusion processes typically requires each layer to be fused before the next can be deposited. The purpose of…

Abstract

Purpose

Additive manufacturing (AM) of thermoplastic polymers for powder bed fusion processes typically requires each layer to be fused before the next can be deposited. The purpose of this paper is to present a volumetric AM method in the form of deeply penetrating radio frequency (RF) radiation to improve the speed of the process and the mechanical properties of the polymer parts.

Design/methodology/approach

The focus of this study was to demonstrate the volumetric fusion of composite mixtures containing polyamide (nylon) 12 and graphite powders using RF radiation as the sole energy source to establish the feasibility of a volumetric AM process for thermoplastic polymers. Impedance spectroscopy was used to measure the dielectric properties of the mixtures as a function of increasing graphite content and identify the percolation limit. The mixtures were then tested in a parallel plate electrode chamber connected to an RF generator to measure the heating effectiveness of different graphite concentrations. During the experiments, the surface temperature of the doped mixtures was monitored.

Findings

Nylon 12 mixtures containing between 10% and 60% graphite by weight were created, and the loss tangent reached a maximum of 35%. Selective RF heating was shown through the formation of fused composite parts within the powder beds.

Originality/value

The feasibility of a novel volumetric AM process for thermoplastic polymers was demonstrated in this study, in which RF radiation was used to achieve fusion in graphite-doped nylon powders.

Article
Publication date: 29 November 2023

Devendra Pratap Singh, Vijay Kumar Dwivedi and Mayank Agarwal

The purpose of this study is to investigate and evaluate the impact of varying proportions of reinforcement on the mechanical properties of a modified Al2O3-LM6 cast composite…

Abstract

Purpose

The purpose of this study is to investigate and evaluate the impact of varying proportions of reinforcement on the mechanical properties of a modified Al2O3-LM6 cast composite under self-pouring temperature conditions. This study aims to determine the optimal mixture proportion of fine powders of Al, Si and xAl2O3 (with x values of 2%, 3% and 4%) through the application of design of experiment (DoE) and statistical analysis using the Minitab software. This study also involved evaluating the microstructural estimation and other physical properties of the cast composite to understand the combined effect of the reinforcement proportion on the material’s properties.

Design/methodology/approach

The researchers initially mixed the powders through ball milling and then compacted the moisture-free powder mix in a closed steel die. The resulting preforms were heated at the self-pouring temperature in an inert environment to fabricate the final cast composite. By applying DoE and performing an analysis of variance (ANOVA), the researchers sought to optimize the mixture proportion that would yield the best mechanical properties.

Findings

The experimental results indicated that a mixture combination of 83.5% Al blended with 12.5% Si and 4% Al2O3 led to the greatest improvement in mechanical properties, specifically in terms of increased density, hardness and impact strength. The ANOVA further supported the interaction effect of each processing parameter on the observed results. The results of this study offer valuable insights for the fabrication of modified Al2O3-LM6 cast composites under self-pouring temperature conditions. The identified optimal mixture proportion provides guidance for manufacturing processes and material selection to achieve improved mechanical properties in similar applications.

Originality/value

This study focuses on a specific composite material consisting of modified Al2O3 and LM6. Although Al2O3 and LM6 have been studied individually in various contexts, the combination of these materials and their impact on mechanical properties under self-pouring temperature conditions is a novel aspect of this research. The researchers use DoE methodology, along with statistical analysis using Minitab software, to optimize the mixture proportion and analyze the data. This systematic approach allows for a comprehensive exploration of the parameter space and the identification of significant factors that influence the mechanical properties of the composite.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 January 1972

P.G. Garrett

Although the technique of electron curing has been well developed, there are very few suitable coatings available.

Abstract

Although the technique of electron curing has been well developed, there are very few suitable coatings available.

Details

Pigment & Resin Technology, vol. 1 no. 1
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 13 February 2007

Firdovsi Tataroglu Sejidov and Yagoub Mansoori

The paper aims to study the effects of introducing oxypropyl segments into the trimethylolpropane (TMP) esters along with lowering the linear chain length from C5‐C9 to C5‐C6 on…

Abstract

Purpose

The paper aims to study the effects of introducing oxypropyl segments into the trimethylolpropane (TMP) esters along with lowering the linear chain length from C5‐C9 to C5‐C6 on the properties of base lubricants.

Design/methodology/approach

Various amounts of oxypropylene segments were introduced into the TMP skeleton and obtained polyols subsequently esterified by pure C5‐, C6‐, and mixture of C5‐C6‐ aliphatic monocarboxylic acids of normal structure (SFAc mixture).

Findings

Introducing oxypropylene segments into TMP skeleton, along with lowering the carboxylic acid chain length from C5‐C9 to C5‐C6, ester base lubricants obtained improved mechanical and wear preventive characteristics.

Research limitations/implications

Because of complexity of obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

Practical implications

The obtained materials have high boiling points under reduced pressure (2 mmHg). Producing higher vacuums will make the distillation process easier.

Originality/value

This paper fulfils detail information on the experimentally preparation of oxypropylated TMPs as synthetic base lubricants. The synthesized compounds showed improved properties such as high viscosity at 100°C, low pour point, high flash point, and totally excellent viscosity‐temperature properties than simple TMP esters and some literature reported ester base lubricants.

Details

Industrial Lubrication and Tribology, vol. 59 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

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