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1 – 10 of over 121000Shekhar P. Tambe, Shwetambari D. Jagtap, Ramakant N. Choudhari and B.P. Mallik
The performance of epoxy coating on metal substrate at low temperature and high humidity application has adverse effect on cure rate, film properties and adhesion. In recent…
Abstract
Purpose
The performance of epoxy coating on metal substrate at low temperature and high humidity application has adverse effect on cure rate, film properties and adhesion. In recent years, several advanced amine cross-linking agents having superior curing ability at low temperature application environment have been introduced. The aim of this paper is to study the properties of epoxy-based coating cured with different cross-linking agents designed for low temperature application at different environmental conditions.
Design/methodology/approach
Series of cross linking agents such as modified cycloaliphatic amine (H1), polyamine adduct (H2), modified aliphatic ketamine (H3), phenalkamine (H4) and phenalkamide (H5) have been studied to evaluate their performance in epoxy compositions when cured at four environmental conditions, i.e. at ambient and sub-ambient temperatures with 60 and 90 per cent relative humidity, respectively. The effect of curing conditions was investigated by evaluating different physico-mechanical properties. Dynamic mechanical analyser technique was used to determine glass transition temperature (Tg) and cross-link density (ρ) of coatings. Anticorrosive properties of coatings also have been studied by electrochemical impedance spectroscopy.
Findings
The outcome of this study is expected to generate new insight into the curing behaviour of epoxy coating using different cross-linking agents which are recommended for low temperature application. Optimum physico-mechanical and corrosion resistance properties have been obtained by phenalkamine curing agent at low temperature and high humidity condition.
Practical implications
This study is an experimental approach to select the better cross-linking agent for low temperature application. Different test conditions were measured for understanding the performance of epoxy coating cured at different environmental condition.
Originality/value
The understanding reaction mechanism of the epoxy resin with cross-linking agent at different environmental condition is the great challenge and is hardly investigated in the literature. Therefore, in this research, the influence of climatic conditions and type of cross-linking agents on curing behaviour of epoxy-based coating was investigated.
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Yigong Liu, Qudus Hamid, Jessica Snyder, Chengyang Wang and Wei Sun
This paper aims to present a solid freeform fabrication-based in situ three-dimensional (3D) printing method. This method enables simultaneous cross-linking alginate at ambient…
Abstract
Purpose
This paper aims to present a solid freeform fabrication-based in situ three-dimensional (3D) printing method. This method enables simultaneous cross-linking alginate at ambient environmental conditions (temperature and pressure) for 3D-laden construct fabrication. The fabrication feasibility and potentials in biomedical applications were evaluated.
Design/methodology/approach
Fabrication feasibility was evaluated as the investigation of fabrication parameters on strut formability (the capability to fabricate a cylindrical strut in the same diameter as dispensing tip) and structural stability (the capability to hold the fabricated 3D-laden construct against mechanical disturbance). Potentials in biomedical application was evaluated as the investigation on structural integrity (the capability to preserve the fabricated 3D-laden construct in cell culture condition).
Findings
Strut formability can be achieved when the flow rate of alginate suspension and nozzle travel speed are set according to the dispensing tip size, and extruded alginate was cross-linked sufficiently. A range of cross-linking-related fabrication parameters was determined for sufficient cross-link. The structural stability and structural integrity were found to be controlled by alginate composition. An optimized setting of the alginate composition and the fabrication parameters was determined for the fabrication of a desired stable scaffold with structural integrity for 14 days.
Originality/value
This paper reports that in situ 3D printing is an efficient method for 3D-laden construct fabrication and its potentials in biomedical application.
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Riccardo Albertoni, Monica De Martino and Paola Podestà
The purpose of this paper is to focus on the quality of the connections (linkset) among thesauri published as Linked Data on the Web. It extends the cross-walking measures with…
Abstract
Purpose
The purpose of this paper is to focus on the quality of the connections (linkset) among thesauri published as Linked Data on the Web. It extends the cross-walking measures with two new measures able to evaluate the enrichment brought by the information reached through the linkset (lexical enrichment, browsing space enrichment). It fosters the adoption of cross-walking linkset quality measures besides the well-known and deployed cardinality-based measures (linkset cardinality and linkset coverage).
Design/methodology/approach
The paper applies the linkset measures to the Linked Thesaurus fRamework for Environment (LusTRE). LusTRE is selected as testbed as it is encoded using a Simple Knowledge Organisation System (SKOS) published as Linked Data, and it explicitly exploits the cross-walking measures on its validated linksets.
Findings
The application on LusTRE offers an insight of the complementarities among the considered linkset measures. In particular, it shows that the cross-walking measures deepen the cardinality-based measures analysing quality facets that were not previously considered. The actual value of LusTRE’s linksets regarding the improvement of multilingualism and concept spaces is assessed.
Research limitations/implications
The paper considers skos:exactMatch linksets, which belong to a rather specific but a quite common kind of linkset. The cross-walking measures explicitly assume correctness and completeness of linksets. Third party approaches and tools can help to meet the above assumptions.
Originality/value
This paper fulfils an identified need to study the quality of linksets. Several approaches formalise and evaluate Linked Data quality focusing on data set quality but disregarding the other essential component: the connection among data.
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The problem of the analytical modeling of macromolecular systems with branching is solved by the statistical polymer, which is based on consideration of averaged structures. All…
Abstract
The problem of the analytical modeling of macromolecular systems with branching is solved by the statistical polymer, which is based on consideration of averaged structures. All interactions are described in terms of statistical polymers. Cross‐linking is considered as a result of interactions inside statistical polymers. It is concluded that cross‐linking may result in the formation of infinitely hard structures and gelling. Thermodynamic functions of statistical polymers are derived and employed for simulation of the evolution of a non‐equilibrium polymeric system. Equations for the evaluation of various parameters of polymeric systems with branching are derived. Theoretical results are used for the preparation of new materials (having a branched, cross‐linked structure) with forecasted properties.
Marta Aurelia Horianski, Juan Manuel Peralta and Luis Alberto Brumovsky
The purpose of this study was to analyze the influence of epichlorohydrin (ECH) concentration and reaction time on the food-grade resistant starch production and its pasting…
Abstract
Purpose
The purpose of this study was to analyze the influence of epichlorohydrin (ECH) concentration and reaction time on the food-grade resistant starch production and its pasting properties by using native cassava starch of Misiones-Argentina origin.
Design/methodology/approach
Cassava starch was modified using ECH (0.30 and 0.15 per cent) during 4 or 8 h. Digestibility was evaluated by determining resistant starch as total dietary fiber. Pasting properties and the cross-linking degree were studied using a micro-viscoamylograph (Brabender).
Findings
Resistant starch content was not influenced by ECH concentration and reaction time. Cross-linking was detected at higher reaction times (8 h) and ECH concentrations (0.30 per cent), where a decrease in viscosity peaks by more than 80 per cent was observed. Both pasting temperature and breakdown were increased, whereas a decrease in retrogradation was detected.
Practical implications
Starches can be suitable for different food applications. This is because of the ability to modify its pasting properties and the invariability of the in vitro digestibility of cassava starch as a result of using ECH (at concentrations approved by local and regional legislation) and reaction times of 4 and 8 h.
Originality/value
Information related to the modification of cassava starch using ECH is scarce or not available nowadays in literature.
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Zheqing Gong, Shusen Cao, Zhibin Cai and Lijun Chen
There are three double bonds in the chemical structure of diallyl maleate. The purpose of this study is that the acrylate is modified with diallyl maleic anhydride to make the…
Abstract
Purpose
There are three double bonds in the chemical structure of diallyl maleate. The purpose of this study is that the acrylate is modified with diallyl maleic anhydride to make the propionate resin present a spatial network structure, thereby improving the performance of the acrylate resin.
Design/methodology/approach
Methyl methacrylate (MMA) and butyl acrylate(BA) were used as were used as main monomers. Diallyl maleate (DAM) was used as crosslinking monomer and dodecafluoroheptyl methacrylate (DFMA) was used as fluoromonomer. Potassium persulfate (KPS) was used as thermal decomposition initiator, sodium lauryl sulfate (AS) and sodium dodecyl sulfonate (SDS) were used as anionic emulsifiers, and EFS-470 (Alkyl alcohol polyether type nonionic emulsifier) was a non-ionic emulsifier.
Findings
Through optimizing the reaction conditions, the uniform and stable latex is obtained. The polymer of structure was characterized by Fourier transform infrared spectroscopy (FTIR). Thermogravimetric analysis (TGA) and contact angle (CA) were tested on latex films. The particle size and distribution range of emulsion were tested with nano particle size analyzer.
Originality/value
The experimental results showed that the thermal decomposition temperature of the acrylic coating film increased by 20.56°C after modification. In addition, the effect of cross-linking density on the water contact angle of the fluorocarbon groups in DFMA when they migrate to the surface of the latex film during drying has been explored. The experimental results show that a higher degree of cross-linking will hinder the migration of fluorocarbon groups to the surface of the resin film.
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Yongzheng Zhang, Evangelos Milios and Nur Zincir‐Heywood
Summarization of an entire web site with diverse content may lead to a summary heavily biased towards the site's dominant topics. The purpose of this paper is to present a novel…
Abstract
Purpose
Summarization of an entire web site with diverse content may lead to a summary heavily biased towards the site's dominant topics. The purpose of this paper is to present a novel topic‐based framework to address this problem.
Design/methodology/approach
A two‐stage framework is proposed. The first stage identifies the main topics covered in a web site via clustering and the second stage summarizes each topic separately. The proposed system is evaluated by a user study and compared with the single‐topic summarization approach.
Findings
The user study demonstrates that the clustering‐summarization approach statistically significantly outperforms the plain summarization approach in the multi‐topic web site summarization task. Text‐based clustering based on selecting features with high variance over web pages is reliable; outgoing links are useful if a rich set of cross links is available.
Research limitations/implications
More sophisticated clustering methods than those used in this study are worth investigating. The proposed method should be tested on web content that is less structured than organizational web sites, for example blogs.
Practical implications
The proposed summarization framework can be applied to the effective organization of search engine results and faceted or topical browsing of large web sites.
Originality/value
Several key components are integrated for web site summarization for the first time, including feature selection and link analysis, key phrase and key sentence extraction. Insight into the contributions of links and content to topic‐based summarization was gained. A classification approach is used to minimize the number of parameters.
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Crystal Drakes, Adrian Cashman, Eric Kemp-Benedict and Timothy Laing
The use of socio-economic scenarios in small island developing states (SIDS) when assessing, and planning for, the impacts of global changes on national socioeconomic and…
Abstract
Purpose
The use of socio-economic scenarios in small island developing states (SIDS) when assessing, and planning for, the impacts of global changes on national socioeconomic and environmental systems is still in its infancy. The research conducts a cross-scale foresight scenario exercise to produce regional scenarios and national storylines for Caribbean islands that are of “partial” consistency to the shared socioeconomic pathways (SSPs) and representative concentration pathways (RCPs) and shows how future socioeconomic and climatic changes can be applied to inform natural resource management decisions.
Design/methodology/approach
To develop the scenarios, the study uses a three-staged linking process using mixed methods to “triangulate” each technique to compensate for weaknesses of one method by introducing a complementary method at each stage. A participatory-expert stepwise approach with feedback loops is used and complemented with a climate sensitive tourism water demand model.
Findings
Four regional exploratory socio-economic scenarios were constructed that are partially consistent with global scenarios. In addition, national storylines for four island states were developed based on the regional scenarios. Using RCP 4.5 hotel water demand in Barbados is estimated under three of the regional scenarios based on compatibility. The results indicate there is a 17% difference between the highest and lowest estimated water demand, indicating the effect of varying socio-economic conditions on water demand.
Originality/value
The paper contributes to the literature by presenting regional socio-economic scenarios, specifically for SIDS, that are partially consistent with both global climatic RCPs and SSPs using a cross-scale approach. The scenarios are then used to demonstrate how future socio-economic pathways impact on freshwater demand.
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Amina Amara, Mohamed Ali Hadj Taieb and Mohamed Ben Aouicha
The intensive blooming of social media, specifically social networks, pushed users to be integrated into more than one social network and therefore many new “cross-network”…
Abstract
Purpose
The intensive blooming of social media, specifically social networks, pushed users to be integrated into more than one social network and therefore many new “cross-network” scenarios have emerged, including cross-social networks content posting and recommendation systems. For this reason, it is mightily a necessity to identify implicit bridge users across social networks, known as social network reconciliation problem, to deal with such scenarios.
Design/methodology/approach
We propose the BUNet (Bridge Users for cross-social Networks analysis) dataset built on the basis of a feature-based approach for identifying implicit bridge users across two popular social networks: Facebook and Twitter. The proposed approach leverages various similarity measures for identity matching. The Jaccard index is selected as the similarity measure outperforming all the tested measures for computing the degree of similarity between friends’ sets of two accounts of the same real person on two different social networks. Using “cross-site” linking functionality, the dataset is enriched by explicit me-edges from other social media websites.
Findings
Using the proposed approach, 399,407 users are extracted from different social platforms including an important number of bridge users shared across those platforms. Experimental results demonstrate that the proposed approach achieves good performance on implicit bridge users’ detection.
Originality/value
This paper contributes to the current scarcity of literature regarding cross-social networks analysis by providing researchers with a huge dataset of bridge users shared between different types of social media platforms.
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Globalisation is generally defined as the “denationalisation of clusters of political, economic, and social activities” that destabilize the ability of the sovereign State to…
Abstract
Globalisation is generally defined as the “denationalisation of clusters of political, economic, and social activities” that destabilize the ability of the sovereign State to control activities on its territory, due to the rising need to find solutions for universal problems, like the pollution of the environment, on an international level. Globalisation is a complex, forceful legal and social process that take place within an integrated whole with out regard to geographical boundaries. Globalisation thus differs from international activities, which arise between and among States, and it differs from multinational activities that occur in more than one nation‐State. This does not mean that countries are not involved in the sociolegal dynamics that those transboundary process trigger. In a sense, the movements triggered by global processes promote greater economic interdependence among countries. Globalisation can be traced back to the depression preceding World War II and globalisation at that time included spreading of the capitalist economic system as a means of getting access to extended markets. The first step was to create sufficient export surplus to maintain full employment in the capitalist world and secondly establishing a globalized economy where the planet would be united in peace and wealth. The idea of interdependence among quite separate and distinct countries is a very important part of talks on globalisation and a significant side of today’s global political economy.
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