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1 – 10 of 673Seng‐Neon Gan and Kim‐Teck Teo
Reports the effects of composition and curing temperature on the film properties of three water reducible enamels prepared from palm stearin alkyds. The properties studied were…
Abstract
Reports the effects of composition and curing temperature on the film properties of three water reducible enamels prepared from palm stearin alkyds. The properties studied were hardness, flexibility, and adhesion. While all the formulations exhibit excellent adhesion, generally increasing the melamine content and curing temperature can increase the hardness but reduce the resistance to cracking and deformation of the coating. Applies Fourier transform infra‐red spectroscopy (FTIR) to the study of the curing reactions. Finds that FTIR is able to identify the predominant cross‐linking reactions.
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Bo Wang, Yanhua Zhang, Haiyan Tan and Jiyou Gu
The purpose of the study was to prepare melamine-urea-formaldehyde (MUF) resin that would be resistant to boiling water and high temperature and exhibit low formaldehyde emission.
Abstract
Purpose
The purpose of the study was to prepare melamine-urea-formaldehyde (MUF) resin that would be resistant to boiling water and high temperature and exhibit low formaldehyde emission.
Design/methodology/approach
The authors prepared MUF resin with different F/(M + U) and changed the amount of melamine added, through the analysis of MUF resin properties to get the best reaction parameters, and used different amino acid cure systems including NH4Cl cured the resin.
Findings
Resin’s heat resistance and water resistance are mainly determined by the amount of melamine added, and formaldehyde emission of the plywood can be changed by adjusting F/(M + U). The peak temperature of the curing agent-cured resin increases as compared with the self-curing resin. Stronger the acidity of curing agent, faster the viscosity increased in probation period and lower the bonding strength and heat resistance of the resin.
Research limitations/implications
Melamine improves the heat resistance and water resistance of the resin. When the amount of melamine is more than a certain value, water resistance of the resin decreased.
Practical implications
MUF resin that is resistant to boiling water and exhibits low formaldehyde emission can be used in high temperature, high humidity and strict formaldehyde emission environment and can also be combined with other materials.
Social implications
It was helpful to reduce the effect of formaldehyde emission on people’s health and environmental pollution and is also beneficial for the expansion of the application range of aldehyde resin.
Originality/value
The originality is twofold: the influence of the acid strength of curing agent on the bonding strength of the resin adhesive and the method for preparing high performance MUF resin by following the traditional process.
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A‐A.M.A. Nada, E.A.M. Youssef and K.N. Abdel‐Nour
Presents findings from a study of the effects of treating unbleached bagasse paper sheets with different resin solutions. Unbleached kraft bagasse paper sheets were treated with…
Abstract
Presents findings from a study of the effects of treating unbleached bagasse paper sheets with different resin solutions. Unbleached kraft bagasse paper sheets were treated with different resin solutions such as nitrocellulose, melamine formaldehyde, silicone, short and medium alkyd resin and the physico‐mechanical properties of the modified paper sheets were tested. The strength properties of treated paper sheets were highly improved especially in the case of treatment with melamine formaldehyde and silicone resin solutions. The effect of dipping time of paper sheets in different concentrations of resin solution on the strength properties was also investigated. Physico‐mechanical properties of thermally treated modified paper sheets with resins were also clarified. Concludes that promising results in the improvement of insulation of treated paper sheets with resin are obtained by studying the dielectric‐electric properties.
Jan Mei Soon-Sinclair, Rounaq Nayak and Louise Manning
The 2008 Chinese melamine milk scandal resulted in six reported fatalities and affected around 300,000 children, of whom 54,000 were hospitalised. Previous studies have used…
Abstract
Purpose
The 2008 Chinese melamine milk scandal resulted in six reported fatalities and affected around 300,000 children, of whom 54,000 were hospitalised. Previous studies have used linear approaches to examine the root causes of the melamine milk scandal.
Design/methodology/approach
In the present study, we applied a systems approach to the melamine milk scandal to identify the complex systems-level failures across the supply chain leading to the incident and why food fraud incidents such as this occurred in the dairy sector. Additionally, systemic failures associated with food fraud vulnerability factors were considered (i.e. opportunities, motivation and control measures).
Findings
48 contributory factors of influence were identified and grouped across six sociotechnical levels across the Chinese dairy system, from government to equipment and surroundings. Lack of vertical integration (processes and communication) contributed to the failure. When viewed from a broader perspective, the melamine milk scandal can be linked to a series of human errors and organisational issues associated with government bodies, the dairy supply chain, individual organisations and management decisions and individual actions of staff or processes.
Practical implications
This approach is of value to policymakers and the industry as it supports public health investigations of food fraud incidents and proactive food safety management.
Originality/value
To the best of our knowledge, this is the first study to analyse a food safety or fraud incident using the AcciMap approach and the food fraud vulnerability assessment (FFVA) technique. AcciMap analysis is applied to both unintentional and intentional aspects of the incident.
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This paper aims to analyze the factors that influence urban consumers' attitudes towards food safety after the melamine scandal.
Abstract
Purpose
This paper aims to analyze the factors that influence urban consumers' attitudes towards food safety after the melamine scandal.
Design/methodology/approach
Based on the research about the attitudes of urban consumers in Nanjing towards the safety of milk powder after the melamine scandal in 2008, this paper adopts the ordered logit model to test which factors significantly influence consumers' attitudes.
Findings
The findings suggest that: first, there is a common concern among consumers about the safety of milk powder after the melamine scandal; second, according to the research, the concern is in inverse relation to the level of educational attainment, consumers' awareness of food safety incidents and their opinion of governments' action after the incident. Moreover, those who always have a concern about the safety of the alternatives to milk powder are more easily affected.
Originality/value
Different from other researches, the paper focuses on consumers' attitudes towards food safety by studying a specific case, namely the melamine scandal.
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Linjie Su, Bohong Li, Dongyu Zhao, Chuanli Qin and Zheng Jin
The purpose of this paper is to prepare a new modified activated carbon fibers (ACFs) of high specific capacitance used for electrode material of supercapacitor.
Abstract
Purpose
The purpose of this paper is to prepare a new modified activated carbon fibers (ACFs) of high specific capacitance used for electrode material of supercapacitor.
Design/methodology/approach
In this study, the specific capacitance of ACF was significantly increased by using the phenolic resin microspheres and melamine as modifiers to prepare modified PAN-based activated carbon fibers (MACFs) via electrospinning, pre-oxidation and carbonization. The symmetrical supercapacitor (using MACF as electrode) and hybrid supercapacitor (using MACF and activated carbon as electrodes) were tested in term of electrochemical properties by cyclic voltammetry, AC impedance and cycle stability test.
Findings
It was found that the specific capacitance value of the modified fibers were increased to 167 Fg-1 by adding modifiers (i.e. 20 wt.% microspheres and 15 wt.% melamine) compared to that of unmodified fibers (86.17 Fg-1). Specific capacitance of modified electrode material had little degradation over 10,000 cycles. This result can be attributed to that the modifiers embedded into the fibers changed the original morphology and enhanced the specific surface area of the fibers.
Originality/value
The modified ACFs in our study had high specific surface area and significantly high specific capacitance, which can be applied as efficient and environmental absorbent, and advanced electrode material of supercapacitor.
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Hung‐Yi Lu, Hsin‐Ya Hou, Tzong‐Horng Dzwo, Yi‐Chen Wu, James E. Andrews, Shao‐Ting Weng, Mei‐Chun Lin and Jun‐Ying Lu
The melamine milk scandal caused a crisis of confidence in food containing dairy products. The purpose of this paper is to explore the determinants of precautionary behaviour to…
Abstract
Purpose
The melamine milk scandal caused a crisis of confidence in food containing dairy products. The purpose of this paper is to explore the determinants of precautionary behaviour to avoid food containing dairy products among Taiwanese college students.
Design/methodology/approach
Of the total respondents selected using a multistage cluster sampling plan, 1,213 respondents completed the questionnaire.
Findings
The survey results showed that subjective norms, attitude, perceived behavioural control, attention to news, and perceived credibility of information are significantly associated with the intention to take precautionary behaviour.
Originality/value
The paper developed a modified theory of planned behaviour (TPB) that focused on attention and perceived credibility of milk scandal‐related information as additional determinants of precautionary behaviour to avoid food containing dairy products. The inclusion of attention and perceived credibility of information constructs enabled a better model fit than that of the TPB model.
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Zaker Bahreini, Vahid Heydari and Zahra Namdari
Mechanical and chemical properties of acrylic-melamine automotive clear coat in the presence of different percentages of well dispersed nano-layered sodium montmorillonite…
Abstract
Purpose
Mechanical and chemical properties of acrylic-melamine automotive clear coat in the presence of different percentages of well dispersed nano-layered sodium montmorillonite (Na-MMT) silicate particles were investigated. For this purpose, prepared dry clear coat film samples were subjected to the entire standard test series, usually carried out in automotive coating industry.
Design/methodology/approach
Effects of adding different percentages of nano-layered silicate on mechanical and chemical properties of acrylic-melamine automotive clear coat were investigated. To increase the compatibility of nanoclays with polymer matrix of clear coat, the surface of nanoclays was modified by benzalkonium chloride as a cationic surfactant. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used for characterization and comparison between clays before and after modification, and also after dispersion in coating. Prepared dry clear coat film samples subjected to the test series are usually carried out in automotive coating industry.
Findings
The results indicated that incorporation of 1 and 2 Wt.% of nano-layered silicate caused desired improvement in chemical and physical properties of the acrylic-melamine clear coat. Increasing the percentage of nanoclay to over 2 Wt.% caused damage in some properties such as hardness, cupping and gloss.
Research limitations/implications
All materials and methods were used in this research are industrial grade. Therefore, the introduced modified clear coat sample has potential for commercial production as an automotive clear coat.
Originality/value
As far as it was searched in the literature, effects of adding nanoclay particles on mechanical and physical properties of different clear coats, such as epoxy clear coat, have been investigated in a few researches, but in this research, common and special tests which are necessary in automotive coating industry have been ignored. In the present study for the first time, acrylic-melamine clear coat was subjected to modification using nano-clay, and also, the most common industrial test methods were used for investigation of mechanical and chemical properties.
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It may be hard to believe that system furniture has only been in existence for twenty years, but no real analysis of office work was carried out until Herman Miller formed its…
Abstract
It may be hard to believe that system furniture has only been in existence for twenty years, but no real analysis of office work was carried out until Herman Miller formed its Research Corporation in 1960 under the direction of Robert Propst, leading to the launch of Action Office 1 in 1964. It was claimed to have a ‘forgiving’ nature because of the ease of revision allowed by breaking the workstation down into small components but it was not a commercial success — cost was one major drawback. Further design work gave rise to Action Office 2, still the brand leader in the UK and the progenitor of numerous copies.
The paper deals with the mode of film formation from urea–formaldehyde and melamine–formaldehyde resins combined with alkyd resin based on castor oil‐modified alkyd. The…
Abstract
The paper deals with the mode of film formation from urea–formaldehyde and melamine–formaldehyde resins combined with alkyd resin based on castor oil‐modified alkyd. The properties of hardened coatings (such as hardness, chemical stability, and adhesion to substrate) were followed in dependence on the ratios of reaction components. An apparatus was built for measuring the formaldehyde emissions escaping from the solid coating films. The determination was performed by the pararosaniline method. The addition of imidazolidine in a concentration up to 10 per cent can reduce the emissions of formaldehyde escaping from the solid films to a considerable amount.
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