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The purpose of this paper is to investigate the friction and wear performance of pure polycarbonate (PC) and 5-30 per cent wollastonite-filled (by weight) PC were comparatively evaluated under dry sliding conditions. Wear tests were carried out at room temperature under the loads of 5-20 N and at the sliding speeds of 0.5-1.5 m/s.

The microstructures of the wollastonite, pure PC and composites were examined by optical microscopy, scanning electron microscopy, energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) analysis. The friction and wear tests were realized using a pin-on-disk arrangement against the hardened AISI 4140 steel.

The result of this study indicated that the coefficients of friction wear rate of the materials were significantly influenced by an increase in wollastonite content. The friction coefficient of the PC was getting decreased from 0.457 to 0.198 with an increase in wollastonite content, depending on applied loads and sliding speeds. On the other hand, the results showed that the wear rates of pure PC and wollastonite-filled PCs decreased with an increase in loads. The wear rate of the PC decreased from 1.2 × 10−6 to 8.7 × 10−6 mm3/m with an increase in wollastonite content, depending on applied loads.

There are many reports which deal with the friction and wear performance of the polymers and polymer composites. However, the effect of wollastonite effect on tribological performance of PC has up to now not been extensively researched.

The purpose of this research is to show that wavelets are mathematical tools capable of separating vibration data into different frequency components, allowing the study of each component with a resolution matched to its specific time scale. Wavelets have advantages over traditional Fourier methods, particularly when a signal contains sharp spikes, discontinuities, and transients.

This paper presents a brief description of wavelets and shows their application to the analysis of typical transient signals due to vibrations in a steel‐reinforced concrete beam.

The research clearly shows that it is possible to evaluate modes and components separately by using the wavelet analysis.

The beam analysed can be used as a simple model of other more complicated structures, such as bridges and other high scale civil engineering constructions, where vibration analysis is a key issue for maintenance and failure assessments, thus representing an alternative mathematical tool for condition monitoring.

This chapter analyses a range of media outputs produced to raise awareness of the campaign of forced sterilisation conducted in Peru during the period 1993–1998. Focusing in detail on the Quipu Project the authors investigate the ways in which different media configure differently witness subjects, audiences and listeners. The chapter also analyses the effectiveness of these media outputs within the contexts of human rights discourses.

The chapter is framed by narrative theories of documentary video production, new media technology and intermediality. The authors also draw on theories of witnessing that have emerged in critical studies of witness testimony in video and new media. It uses secondary data, that is, the testimonies of women already collected, selected and, in most cases, edited by documentary makers and campaigners.

The case studies compare the ways in which conventional video documentary and techniques of digital storytelling transform the content of women’s testimony.

Funding limitations have meant that progress on the site was, at the time of writing, temporarily suspended. We therefore analysed the pilot, or prototype, of the Quipu Project, which should be viewed as a work in progress. However, a more developed site for the Quipu Project went live after the chapter was completed.

This chapter represents the first attempt to analyse the effectiveness of an experimental project such as the Quipu Project. The authors were given access by the curators of the project to the site at various stages of its construction. The chapter provides insights into the potential of digital technology to create opportunities for media outputs to internationalise interventions into campaigns for justice and reparation.

The Spanish wine sector has gained ever greater relevance not only in economic terms but also from a social and environmental perspective. One Spanish region with a deeply rooted history of growing and producing wine is the Canary Islands, and specifically the island of Tenerife. The wine sector there has undergone notable evolution since the end of the past century. The main aim of these changes has been to improve the quality of Canarian wines, although it is also crucial to design marketing strategies that contribute to maintaining and increasing market share. In this context, it is essential to improve our knowledge of wine consumption among the population, especially given the scarcity of studies that analyze consumption preferences. Thus, the aim of this study is to identify wine consumption profiles.

This study uses data from a survey carried out on a representative sample of 1,028 Tenerife residents. Discrete choice models are estimated to identify profiles of wine consumers.

The main results show that the probability of consuming wine is the greatest among adult men compared to a lower consumption by younger individuals and women. Furthermore, it was shown that the probability of occasional consumption increases with higher educational levels.

This study examines in depth the individual factors that influence decisions on wine consumption (frequency and amount) in Tenerife (Canary Islands), which has a wine-growing landscape that produces several unique grape varieties. The study quantifies the probability of wine consumption depending on resident individuals’ sociodemographic characteristics. Thus, it contributes to a greater understanding of demand and consumption patterns in the island´s wine sector and allows comparisons to be made with studies for other geographical areas. It is, therefore, a valuable framework for designing targeted marketing strategies to increase consumption and attract demand from potential consumers with specific characteristics.

The aim of the present paper is that three long-chain hydroxyethyl alkylimidazolium hexafluorophosphate ionic liquids (ILs) were synthesized and evaluated as lubricants for steel-steel contacts at room temperature and boundary lubrication conditions. Hydroxyethyl functional group and alkyl chain length effect on the physicochemical and fretting tribological behaviors of the ILs was comparatively investigated, as compared to traditional dialkylimidazolium ILs.

The fretting friction and wear tests were carried out using an Optimol SRV-IV oscillating reciprocating friction and wear tester. The worn surface was observed and analyzed by scanning electron microscope and X-ray photoelectron spectroscopy. The electrochemical corrosion behavior of copper disks in selected imidazolium-based ionic liquids was studied using a CHI660B electrochemical workstation.

This can be seen by comparing the results for the non-hydroxyl ILs and hydroxyl ILs that the latter exhibited the littler friction coefficient, the smaller wear volume, although the latter electrochemical corrosion behavior of copper disks is slightly higher than the former. The results also revealed that the ILs with a longer alkyl chain displayed larger viscosities, better anti-corrosion capacities, higher hydrophobic properties and more excellent friction-reducing and anti-wear performance than those with a shorter alkyl chain.

This work might offer new knowledge in the design and application of new ILs as lubricants; it also confirms some in-depth physicochemical questions, e.g. the function mechanism, the correlations between structure and performance. Additionally, a proposed interaction model between the ILs and the friction substrate has been given.

Condition assessment on reinforced concrete (RC) structures is one of the critical issues as a result of structure degradation due to aging in many developed countries. The purpose of this paper is to examine the sensitivity and reliability of the conventional dynamic response approaches, which are currently applied in the RC structures. The key indicators include: natural frequency and damping ratio. To deal with the non-linear characteristics of RC, the concept of random decrement is applied to analyze time domain data and a non-linear damping curve could be constructed to reflect the condition of RC structure.

A full-scale RC structure was tested under ambient vibration and the impact from a rubber hammer. Time history data were collected to analyze dynamics parameters such as natural frequency and damping ratio.

The research demonstrated that the measured natural frequency is not a good indicator for integrity assessment. Similarly, it was revealed that the traditional theory of viscous damping performed poorly for the RC with non-linear characteristics. To address this problem, a non-linear curve is constructed using random decrement and it can be used to retrieve the condition of the RC structure in a scientific manner.

The time domain analysis using random decrement can be used to construct a non-linear damping curve. The results from this study revealed that the damage of structure can be reflected from the changes in the damping curves. The non-linear damping curve is a powerful tool for assessing the health condition of RC structures in terms of sensitivity and reliability.

The purpose of this paper is to synthesize a novel kind of crown‐type phosphate ionic liquids with better tribological properties for steel/Al system. The anions of crown‐type phosphate ionic liquids contain no F element, which are non‐corrosive to metal.

To improve the tribological properties of ionic liquid lubricants for the extremely difficult system of the steel‐against‐aluminum metal couple, novel crown‐type phosphate ionic liquids were prepared. The tribological properties of the crown‐type phosphate ionic liquids were evaluated at different loads and frequencies on an Optical SRV oscillating friction and wear tester. The morphology and chemical compounds of the wear scars were investigated by scanning electron microscope (SEM) and X‐ray photoelectron spectroscopy (XPS).

Compared with conventional ionic liquids, the novel crown‐type phosphate ionic liquids prepared in the present work exhibit a more excellent anti‐wear ability for steel/Al2024 contact at different loads and frequencies. By the morphological analysis with SEM, less debris was observed in the worn surface lubricated with crown‐type phosphate ionic liquids, though more debris was observed when lubricated with LB106 and LP106. By the XPS analysis, boundary lubrication film composed of aluminum (III) oxide, organometallic compounds, and silicon aluminum phosphate were found in the worn surface. Namely, the tribological behaviors of the crown‐type phosphate ionic liquids could be attributed to their stronger adsorption and tribochemical interactions with the Al alloys.

Because of the higher mean friction coefficients of crown‐type phosphate ionic liquids in the research, researchers are encouraged to modify their structure for better tribological properties.

The crown‐type phosphate ionic liquid exhibited better anti‐wear performance for steel/aluminum contact than the conventional ionic liquids containing F element. This will expand the application of high strength aluminum alloys.

The phosphate ionic liquid is a non‐corrosive liquid and would not cause metal corrosion. Also, the tribological properties of crown‐type phosphate ionic liquid with steel/aluminum contact are better than that of conventional ionic liquids. By the designing of molecular structure, new phosphate ionic liquids will exhibit excellent tribological properties: lower wear volume and lower friction coefficient.

The purpose of this paper is synthesis of oil-soluble non-spherical nanoparticles modified with free phosphorus and sulphur modifier and investigation of their tribological properties as environment-friendly lubricating oil additives.

To study the effect of morphology of nanoparticles on their tribological properties, rice-like CuO nanoparticles were synthesized. To improve the solubility of CuO nanoparticles in organic media, the in-situ surface modification method was used to synthesize these products. The morphology, composition and structure of as-synthesized CuO nanoparticles were investigated by means of transmission electron microscopy, X-ray powder diffraction, thermogravimetric analysis and Fourier transform infrared spectrometry. The tribological properties of as-synthesized CuO nanoparticles as an additive in liquid paraffin (LP) were evaluated with a four-ball tribometer. The morphology and elemental composition of worn steel ball surfaces were analysed by X-ray photoelectron spectroscopy.

It has been found that as-synthesized CuO nanoparticles with rice-like morphology have an average size of 7 and 15 nm along the shorter axle and longer axle, respectively, and can be well-dispersed in LP. Tribological properties evaluation results show that as-synthesized CuO nanoparticles as additives in LP show good friction-reducing, anti-wear and load-carrying capacities, especially under a higher normal load.

Oil-soluble rice-like CuO nanoparticles without phosphorus and sulphur were synthesized and their tribological properties as lubricating oil additives were also investigated in this paper. These results could be very helpful for application of CuO nanoparticles as environment-friendly lubricating oil additives, owing to their free phosphorus and sulphur elements characteristics.

This paper aims to clarify the effects of metallic nanoparticles (NPs) additives and room temperature ionic liquids (ILs) on the tribological performance of electric contacts.

Tribological properties of copper (Cu) and silver (Ag) NPs as lubricant additives in different lubricants of ILs or polyalphaolefin (PAO) oils under applied electric currents were investigated. After tribological tests, morphologies of worn surfaces were observed; meanwhile, lubrication and anti-wear properties were analyzed.

The mixture solution of the IL and Cu NPs showed desirable lubrication and anti-wear properties due to the reduction of electrocorrosion and the enhancement of rolling effects of particles in the contact region. The anti-wear performance of Cu NPs is better than that of Ag NPs due to the difference in the particle size. The PAO oil with the Cu NPs additives showed poor lubrication properties due to the low solubility of the particles in the oil. When the direction of applied current was changed, the friction of the lubricant with better conductivity was more stable in the variation trend.

This paper begins with a study of tribological properties of Cu and Ag NPs as lubricant additives in different lubricants of IL or PAO oils under applied electric currents. The authors then propose several methods and possible solutions which could be implemented to improve the tribological performance of electric contacts.

The purpose of this paper is to study the tribological properties of (C₉H₈N)₄(H₂O)₄[Zr₈P₁₂O₄₀(OH)₈F₈] (designated as ZrPOF-Q1) used as an additive in lithium grease.

The tribological properties of ZrPOF-Q1 as an additive in the lithium grease were evaluated with a four-ball tester. To understand the lubrication mechanism, post-test characterization of the contact tracks was performed via three-dimensional (3D) optical profiler, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS).

The results reveal that ZrPOF-Q1 exhibits good performance in anti-wear, friction-reducing and load-carrying capacity. The action mechanism is estimated through analysis of the worn surface with SEM, EDS and 3D. The results indicate that ZrPOF-Q1 can adhere on the substrate, protecting the rubbed surfaces from a direct contact, even under high load for a long-time test. ZrPOF-Q1 can adhere on the substrate, protecting the rubbed surfaces from a direct contact, even under high load for a long-time test.

This work illustrates that ZrPOF-Q1 as an additive can improve lubricating performance. These tribological properties make ZrPOF-Q1 a promising candidate for lubricant additive.