A copper-(lignin/silica/fatty acids) complex as an antioxidant/electrical conductivity agent for rubber composites (Part iii)

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hoda Sabry Othman ◽  
Maher A. El-Hashash ◽  
S. H. El-Sabbagh ◽  
A. A. Ward ◽  
Galal A.M. Nawwar
Keyword(s):  
Electrical Conductivity ◽  
Antioxidant Activity ◽  
Design Methodology ◽  
Black Liquor ◽  
Coupling Agents ◽  
Rheological Characteristics ◽  
Rubber Composites ◽  
Content Type ◽  
Mechanical And Electrical Properties ◽  
Antioxidant Additives

Purpose Calcium and Zinc lignates were proven to be good antioxidants for rubber composites. The purpose of this paper is to evaluate the copper lignate antioxidant activity along with evaluating its electrical conductivity in rubber composites. Design/methodology/approach The antioxidant activity of the Cu-LSF complex was compared with that of standard commercial antioxidant additives as a green alternative. The rheological characteristics, thermal aging and mechanical and electrical properties were evaluated for the NBR vulcanizates containing the different antioxidants in the presence or absence of coupling agents. Findings Results revealed that the Cu-LSF complex (5 phr) can function as a compatibilizing, antioxidant and electrical conductivity agent. Originality/value The new copper complex prepared from paper-pulping black liquor of wastes could be used as a green antioxidant and electrical conductivity agent in rubber composites.

Utility of copper (lignin/silica/fatty acids) complex derived from rice straw as antioxidant/hardening and fluid resistant agent in nitrile-butadiene rubber composites (PART IV)

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hoda Sabry Othman ◽  
Salwa H. El-Sabbagh ◽  
Galal A. Nawwar
Keyword(s):  
Thermal Stability ◽  
Electrical Conductivity ◽  
Fatty Acids ◽  
Design Methodology ◽  
Rubber Matrix ◽  
Butadiene Rubber ◽  
Rubber Composites ◽  
Content Type ◽  
Nitrile Butadiene Rubber ◽  
Fluid Resistance

Purpose In continuation to the previous work on copper (lignin/silica/fatty acids) (Cu-LSF) complex as a natural antioxidant/electrical conductivity agent for nitrile-butadiene rubber (NBR), this study aims to perform further investigations for NBR vulcanizates loaded with different concentrations of Cu-LSF complex, including swelling behavior and hardness properties, as well as evaluating their thermal stability via thermogravimetric analysis. Design/methodology/approach The behavior of Cu-LSF complex in NBR matrix was compared with that of the standard commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline/N-isopropyl-N′-phenyl-p-phenylenediamine [TMQ/IPPD]). Findings Results revealed that Cu-LSF complex can act as an effective reinforcing and hardening agent, with exhibiting fluid resistance, even when compared with the commercial antioxidants. In comparison with the previous studies on its Zn and Ca analogues and their behavior in different rubber matrixes, Cu-LSF complex showed higher values of hardness and less susceptibility for swelling, respectively. Moreover, Cu-LSF antioxidant activity becomes in accordance with the previous work. Originality/value The new Cu-LSF complex could be used as a green alternative to the commercial antioxidants (TMQ/IPPD) with introducing further advantages to the rubber matrix, such as hardening, fluid resistance and thermal stability.

scholarly journals Extracts of red peppers: antioxidant activity and sensory evaluation

2016 ◽  
Vol 46 (2) ◽  
pp. 228-236 ◽  
Author(s):  
Neuza Jorge ◽  
Carolina Médici Veronezi ◽  
Danusa Cassiano Pereira
Keyword(s):  
Antioxidant Activity ◽  
Ascorbic Acid ◽  
Phenolic Compounds ◽  
Antioxidant Capacity ◽  
Design Methodology ◽  
Reducing Power ◽  
Content Type ◽  
High Antioxidant Activity ◽  
Red Peppers ◽  
Practical Implications

Purpose – This study aims to deal with the evaluation of the antioxidant capacity of lyophilized hydroalcoholic extracts of red peppers in natura. Furthermore, preference was evaluated for the taste and color of soybean oil added red pepper extracts. Design/methodology/approach – The antioxidant capacity was determined by four methods. The content of phenolic compounds, carotenoids and ascorbic acid in the extracts was determined by chromatographic, spectrophotometric and titration methods, respectively. Findings – The results showed that the highest antioxidant capacity was found in Malagueta pepper extract through reducing power (FRAP) method. In this same extract, high amount of phenolic compounds was found. However, the extracts of Bode and Dedo-de-moça peppers had higher amounts of carotenoids and ascorbic acid, respectively. Sensorially, the oil added extracts were preferred. Practical implications – Red peppers are very popular and consumed worldwide, besides being constituted of important phytochemicals. Results showed high antioxidant activity in the extracts of peppers, and high content of phenolic compounds, carotenoids and ascorbic acid mainly in chili. This study highlights the importance of the extracts of red peppers, genus Capsicum, as a source of antioxidants, in addition to vegetable oils. Originality/value – It is important to check the acceptance of the application of extract in vegetable oil, so it can be marketed as a natural antioxidant. This study provides valuable information about the antioxidant capacity of extracts of red peppers and its acceptance.

The influence of localized mechanical stresses on the non-homogeneous distribution of electrical conductivity

2016 ◽  
Vol 35 (6) ◽  
pp. 1983-1995 ◽  
Author(s):  
Ewa Napieralska-Juszczak ◽  
Piotr Napieralski ◽  
Krzysztof Komeza ◽  
Youcef Zeroukhi
Keyword(s):  
Electrical Conductivity ◽  
Design Methodology ◽  
Simulation Method ◽  
Uneven Distribution ◽  
Design Parameters ◽  
Homogeneous Distribution ◽  
Physical Parameters ◽  
Total Resistance ◽  
Content Type ◽  
Practical Implications

Purpose The purpose of this paper is to determine the physical design parameters that influence the total resistance of a twisted conductor (cable). One of the physical parameters characterizing this type of structures is the uneven distribution of resistivity due to hardening, which is the result of stress exerted on the wires during the manufacturing process. Design/methodology/approach The authors have developed a method to take into account the effect of localized hardening on the inhomogeneous distribution of electrical conductivity in the distorted structures of the conductor. To achieve this goal, the authors have implemented a mechanical-electrical simulation method. The resistance characteristics have been measured as a function of mechanical stress. Findings As demonstrated by the results of measurements conducted on various samples and with various cable design parameters, the resistance of a given material (copper or aluminum), expressed as a function of stress, does not depend on the type of force applied. Therefore, the same characteristics may be applied to various cable designs. Practical implications The method presented in this paper enables more detailed investigation of the influence of particular design parameters on the total resistance of a cable. It also provides the ability to determine optimal settings of design parameters. Originality/value The approach is distinct from similar studies because it takes into account the deformed geometry of the conductor and the uneven distribution of the resistivity within a filament. In the literature, it is sometimes stated that the distribution of resistivity in a compacted cable is uneven, but its measurement is deemed impossible. This paper provides a method for determining such a distribution.

scholarly journals Vulnerable adults in police custody

2019 ◽  
Vol 22 (1) ◽  
pp. 5-8
Author(s):  
Ian Cummins
Keyword(s):  
Design Methodology ◽  
Research Literature ◽  
Police Custody ◽  
England And Wales ◽  
Content Type ◽  
Increased Risk ◽  
Vulnerable Adults

Purpose The purpose of this paper is to discuss the recent National Appropriate Adult Network (NAAN) report on the role of the appropriate adult. Design/methodology/approach This paper is based on the NAAN report and a review of relevant policy and research literature. Findings There to Help 2 highlights that there are still significant gaps in the provision of appropriate adult schemes across England and Wales. These gaps potentially place vulnerable adults at increased risk. Originality/value This paper is a review of recent research.

Co-workers’ perceptions of and reactions to employee’s involuntary demotion

2019 ◽  
Vol 41 (4) ◽  
pp. 740-757 ◽  
Author(s):  
Sophie Hennekam ◽  
Subramaniam Ananthram ◽  
Steve McKenna
Keyword(s):  
Design Methodology ◽  
Emotional Responses ◽  
Emotional Reaction ◽  
Content Type ◽  
Informational Justice ◽  
Behavioural Responses ◽  
Behavioural Reaction ◽  
Three Stages ◽  
Depth Interviews ◽  
The Way

Purpose The purpose of this paper is to investigate how individuals perceive and react to the involuntary demotion of a co-worker in their organisation. Design/methodology/approach The authors draw on 46 semi-structured in-depth interviews (23 dyads) with co-workers of demoted individuals. Findings The findings suggest that an individual’s observation of the demotion of a co-worker has three stages: their perception of fairness, their emotional reaction and their behavioural reaction. The perception of fairness concerned issues of distributive, procedural, interpersonal and informational justice. The emotional responses identified were feelings of disappointment/disillusion, uncertainty, vulnerability and anger. Finally, the behavioural reactions triggered by their emotional responses included expressions of voice, loyalty, exit and adaptation. Originality/value Perceptions of (in)justice perpetrated on others stimulate emotional and behavioural responses, which impacts organisational functioning. Managers should therefore pay attention to the way a demotion is perceived, not only by those directly concerned, but also by co-workers as observers.

Consumer value creation through WhatsApp use

2019 ◽  
Vol 32 (4) ◽  
pp. 455-471
Author(s):  
Jorge Cruz-Cárdenas ◽  
Jorge Guadalupe-Lanas ◽  
Ekaterina Zabelina ◽  
Andrés Palacio-Fierro ◽  
Margarita Velín-Fárez ◽  
...  
Keyword(s):  
Latin American ◽  
Value Creation ◽  
Emotional Support ◽  
Design Methodology ◽  
Instant Messaging ◽  
Role Performance ◽  
Content Type ◽  
Consumer Value ◽  
Depth Interviews ◽  
Practical Implications

Purpose The purpose of this paper is to understand in-depth how consumers create value in their lives using WhatsApp, the leading mobile instant messaging (MIM) application. Design/methodology/approach The study adopts the perspective of customer-dominant logic (CDL) and uses a qualitative multimethod design involving 3 focus groups and 25 subsequent in-depth interviews. The research setting was Ecuador, a Latin American country. Findings Analysis and interpretation of the participants’ stories made it possible to identify and understand the creation of four types of value: maintaining and strengthening relationships; improving role performance; emotional support; and entertainment and fun. In addition, the present study proposes a conceptual model of consumer value creation as it applies to MIM. Practical implications Understanding the way consumers create value in their lives using MIM is important not only for organizations that offer MIM applications, but also for those companies that develop other applications for mobile phones or for those who wish to use MIM as an electronic word-of-mouth vehicle. Originality/value The current study is one of the first to address the topic of consumer behavior in the use of technologies from the perspective of CDL; this perspective enables an integrated qualitative vision of value creation in which the consumer is the protagonist.

scholarly journals Advantages and potential challenges of data management in e-maintenance

2019 ◽  
Vol 25 (3) ◽  
pp. 378-396 ◽  
Author(s):  
Arian Razmi-Farooji ◽  
Hanna Kropsu-Vehkaperä ◽  
Janne Härkönen ◽  
Harri Haapasalo
Keyword(s):  
Data Management ◽  
Design Methodology ◽  
Management Practices ◽  
Future Research ◽  
Conceptual Approach ◽  
Content Type ◽  
Different Types ◽  
Maintenance Systems ◽  
Industry Leader ◽  
Practical Implications

Purpose The purpose of this paper is twofold: first, to understand data management challenges in e-maintenance systems from a holistically viewpoint through summarizing the earlier scattered research in the field, and second, to present a conceptual approach for addressing these challenges in practice. Design/methodology/approach The study is realized as a combination of a literature review and by the means of analyzing the practices on an industry leader in manufacturing and maintenance services. Findings This research provides a general understanding over data management challenges in e-maintenance and summarizes their associated proposed solutions. In addition, this paper lists and exemplifies different types and sources of data which can be collected in e-maintenance, across different organizational levels. Analyzing the data management practices of an e-maintenance industry leader provides a conceptual approach to address identified challenges in practice. Research limitations/implications Since this paper is based on studying the practices of a single company, it might be limited to generalize the results. Future research topics can focus on each of mentioned data management challenges and also validate the applicability of presented model in other companies and industries. Practical implications Understanding the e-maintenance-related challenges helps maintenance managers and other involved stakeholders in e-maintenance systems to better solve the challenges. Originality/value The so-far literature on e-maintenance has been studied with narrow focus to data and data management in e-maintenance appears as one of the less studied topics in the literature. This research paper contributes to e-maintenance by highlighting the deficiencies of the discussion surrounding the perspectives of data management in e-maintenance by studying all common data management challenges and listing different types of data which need to be acquired in e-maintenance systems.

An exploratory empirical study of whistleblowing and whistleblowers

2020 ◽  
Vol 27 (3) ◽  
pp. 755-770
Author(s):  
Maria Krambia-Kapardis
Keyword(s):  
Statistical Analysis ◽  
Design Methodology ◽  
Research Topic ◽  
Due Date ◽  
Content Type ◽  
Unethical Behaviour ◽  
Eu Member States ◽  
European Directive ◽  
Original Survey ◽  
Practical Implications

Purpose The purpose of this study is to develop a profile of whistleblowers and to determine whether whistleblowing legislation would encourage those individuals to bring to light some illegal or unethical behaviour that otherwise would remain in the shadows. Design/methodology/approach Having identified whistleblowing correlation, a survey was carried out in Cyprus of actual whistleblowers and could-have-been whistleblowers. Findings Males between 46 and55 years of age, regardless of whether they have dependents or hold senior positions in organizations are significantly more likely to blow the whistle. However, could-have-been whistleblowers did not go ahead because they felt that the authorities would not act on their information. Research limitations/implications Because of the sensitive nature of the research topic and the fact that only whistleblowers or intended whistleblowers could participate in the study, the sample size is limited as a result. This, in turn, limits both the number of respondents in each category (actual and intended) as well as constrains the statistical analysis that could be carried out on the data. Practical implications It remains to be seen whether EU Member States shall implement the European Directive 2019/1937 on the protection of persons who report breaches of Union Law, in its entirety by the due date, namely December 2021. Originality/value This study provides a literature review of whistleblowing and reports an original survey against the backdrop of the European Directive.

Interest rate option hedging portfolios without bank account

2019 ◽  
Vol 37 (1) ◽  
pp. 134-142
Author(s):  
Alberto Bueno-Guerrero
Keyword(s):  
Design Methodology ◽  
Contingent Claim ◽  
Necessary And Sufficient Condition ◽  
Barrier Option ◽  
Bank Account ◽  
Content Type ◽  
Option Hedging ◽  
Hedging Portfolio ◽  
Necessary And Sufficient ◽  
First Time

Purpose This paper aims to study the conditions for the hedging portfolio of any contingent claim on bonds to have no bank account part. Design/methodology/approach Hedging and Malliavin calculus techniques recently developed under a stochastic string framework are applied. Findings A necessary and sufficient condition for the hedging portfolio to have no bank account part is found. This condition is applied to a barrier option, and an example of a contingent claim whose hedging portfolio has a bank account part different from zero is provided. Originality/value To the best of the authors’ knowledge, this is the first time that this issue has been addressed in the literature.

Understanding decoupling in response to corporate governance reform pressures

2015 ◽  
Vol 23 (4) ◽  
pp. 369-382 ◽  
Author(s):  
Mario Krenn
Keyword(s):  
Corporate Governance ◽  
Design Methodology ◽  
Good Governance ◽  
Regulatory Change ◽  
Compliance Monitoring ◽  
Governance Reform ◽  
Firm Level ◽  
Content Type ◽  
Good Corporate Governance ◽  
Actual Use

Purpose – The purpose of this article is to explain under what circumstances firm-level adoption of codes of good corporate governance will more likely be superficial rather than substantive in nature. The article contains lessons for any agency or country that attempts to implement deep and lasting changes in corporate governance via codes of good corporate governance. Design/methodology/approach – The article reviews the literature on compliance with codes of good corporate governance and develops a conceptual model to explain why some firms that have formally adopted a code of good governance decouple this policy from its actual use. Findings – Decoupling in response to the issuance of codes of good corporate governance will be more attractive to firms and also more sustainable under the following conditions: firms’ compliance costs are relatively high firms’ costs of outright and visible non-compliance are relatively high and outsiders’ compliance monitoring costs are relatively high. Originality/value – The article contributes to the debate on compliance and convergence and provides policymakers with a conceptual framework for assessing the likelihood of successful regulatory change in corporate governance.

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