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Zirconia ceramics exhibit high strength and fracture toughness. The purpose of this paper is to research a possibility of crack healing in zirconia ceramics.

ZrO₂/SiC composite ceramics are sintered and subjected to three‐point bending. A surface crack of 100 μm in diameter is formed on each specimen. The cracks are healed and the specimens are tested under bending.

The paper finds that ZrO₂/SiC composite ceramic material had a high crack‐healing ability at a considerably low temperature. For example, a crack of 100 μm in diameter is healed even at 600°C.

The paper provides a low temperature healing and a new mechanism of crack healing.

The paper shows the healing temperature and the minimum time required to heal showed a good proportional relation on the Arrhenius plot at temperatures of 600‐800°C. Moreover, the crack healing is caused by SiO₂ cristobalite produced during the healing.

The purpose of this paper is to study the crack‐healing mechanism of ZrO₂/SiC composite ceramics which have a high crack‐healing ability at low temperature.

The effects of dispersed SiC and the environment on crack‐healing behaviour were investigated. The fatigue strength of crack‐healed specimens was also investigated.

The main conclusions are that for crack‐healing of ZrO₂ ceramics, it is necessary to have both a SiC composite and an oxidative environment; and when ZrO₂/SiC composite ceramics are heat‐treated in air, a phase transformation attributable to the SiC composite results in crack‐healing and improvement of fracture toughness and bending strength.

An appropriate heat treatment for ZrO₂/SiC composite caused not only crack‐healing but also the improvement of fracture toughness, and created a multiplier effect on crack‐healing, bending strength and fracture toughness.

This study aims to develop a polymer cement-based waterproof coating with self-healing capability to efficiently and intelligently solve the building leakage caused by cracking of waterproof materials, along with excellent durability to prolong its service life.

Ion chelators are introduced into the composite system based on ethylene vinyl acetate copolymer emulsion and ordinary Portland cement to prepare self-healing polymer cement-based waterproof coating. Hydration, microstructure, wettability, mechanical properties, durability, self-healing performance and self-healing products of polymer cement-based waterproof coating with ion chelator are investigated systematically. Meanwhile, the chemical composition of self-healing products in the crack was examined.

The results showed that ion chelators could motivate the hydration of C₂S and C₃S, as well as the formation of hydration products (C-S-H gel) of the waterproof coating to improve its compactness. Compared with the control group, the waterproof coating with ion chelator had more excellent water resistance, alkali resistance, thermal and UV aging resistance. When the dosage of ion chelator was 2%, after 28 days of curing, cracks with a width of 0.29 mm in waterproof coating could fully heal and cracks with a width of 0.50 mm could achieve a self-healing efficiency of 72%. Furthermore, the results reveal that the self-healing product in the crack was calcite crystalline CaCO₃.

A novel ion chelator was introduced into the composite coating system to endow it with excellent self-healing ability to prolong its service life. It has huge application potential in the field of building waterproofing.

Sociologists have tended to construct theories of identity based on unitary notions of social location which avoid conceptualizing disjunction and contradiction and which therefore fail to capture certain characteristics of the postcolonial condition. This paper engages in a postcolonial re-reading of sociological theories of practice (in particular, Pierre Bourdieu's notion of habitus). It does so through an analysis of the historical development of the field of health and healing in South Africa. From the beginning of the colonial enterprise, biomedicine resisted amalgamation with other forms of healing and insisted on a monotherapeutic ideology and practice whereas indigenous healing accommodated not only biomedicine, but invited pluralism within and across cultural and ethnic differences. As such, a bifurcated and parallel system of healing emerged, whereby Black South Africans practiced pluralism and white South Africans utilized biomedicine in isolation. This disjuncture became acrimonious in the post-apartheid era as the state attempted to forge a united health system and battle the AIDS epidemic. Despite the historical and contemporary bifurcations within the field of health and healing, people living with AIDS continue to subscribe to a hybrid health ideology. There is, therefore, a structural disjuncture between the realities of consumption within the field of health and healing and the logic of the field as it is articulated in the symbolic struggle raging in the field of power. The field of health and healing is characterized, therefore, by a simultaneous bifurcation and hybridity – which is reflected in HIV-infected South Africans’ beliefs and practices. In order to make sense of this puzzling disjuncture and its impact on subjects’ trajectories of action, this paper draws insight from Pierre Bourdieu's theory of habitus and Homi Bhabha's conceptualization of hybridity – transforming each of them through their synthesis and application to the postcolonial context.

This paper aims to focus on the research progress of intelligent self-healing anti-corrosion coatings in the aviation field in the past few years. The paper provides certain literature review supports and development direction suggestions for future research on intelligent self-healing coatings in aviation.

This mini-review uses a systematic literature review process to provide a comprehensive and up-to-date review of intelligent self-healing anti-corrosion coatings that have been researched and applied in the field of aviation in recent years. In total, 64 articles published in journals in this field in the last few years were analysed in this paper.

The authors conclude that the incorporation of multiple external stimulus-response mechanisms makes the coatings smarter in addition to their original self-healing corrosion protection function. In the future, further research is still needed in the research and development of new coating materials, the synergistic release of multiple self-healing mechanisms, coating preparation technology and corrosion monitoring technology.

To the best of the authors’ knowledge, this is one of the few systematic literature reviews on intelligent self-healing anti-corrosion coatings in aviation. The authors provide a comprehensive overview of the topical issues of such coatings and present their views and opinions by discussing the opportunities and challenges that self-healing coatings will face in future development.

Since Barker, Gupta, and Iantaffi (2007), in both mainstream cultural products and academic literature dealing with BDSM, there has been an increase in emanations of the “healing narrative,” which suggests that BDSM practices offer therapeutic potential. However, no significant attempt has been made to explore in greater detail the problematic relationship between this healing narrative and the history of pathologization of sadomasochistic desires and practices. Barker et al. (2007) rightly point out that in suggesting BDSM has healing potential, one runs the risk of implying that individuals who practice BDSM are in need of healing to begin with. This could be damaging to the image of BDSM, which after centuries of pathologization finally appears to be moving into a realm of acceptability. However, the experiences of BDSM practitioners who describe their practices as healing should not be discounted and could actually help to cultivate a more positive reputation, which makes the issue a political one. In this chapter, through an exploration of the concept of “healing” in cultural objects such as the film Secretary (2002, directed by Steven Shainberg) and the Showtime cable television series Billions (2016–present), this issue will be investigated further, leading to a way out of the apparent double bind. The aim is to come to an understanding of the therapeutic potential of BDSM, which would not only reframe the discourse of pathologization surrounding BDSM but also further the political goal of creating space for BDSM practitioners to explore their desires without having to experience stigmatization.

The purpose of this paper is to add expanded perlite (EP) immobilized microorganisms that replace part of the standard sand in mortar to improve the self-healing ability of mortar cracks and reduce the water absorption of mortar after healing.

Bacillus pseudofirmus spores were immobilized with EP particles as self-healing agents. The effects of adding self-healing agents on the compressive strength of mortar specimens were observed. The ability of mortar specimens to heal cracks was evaluated using crack microscopic observation and water absorption experiments. The filler at the cracks was microscopically analyzed by scanning electron microscope and X-ray diffraction experiments.

First, the internal curing effect of EP promotes the hydration of cement in mortar, which generates more amount and denser crystal structure of Ca(OH)2 at mortar cracks and improves the self-healing ability of mortar. Second, the self-healing ability of mortar improves with the increase of self-healing agent admixture. Adding a self-healing agent of high admixture makes the planar undulation of calcite crystal accumulation at mortar cracks more significant. Finally, the initial crack widths that can be completely healed by adding EP and self-healing agents to the mortar are 200 µm and 600 µm, respectively.

The innovation points of this study are as follows. (1) The mechanism of the internal curing effect of EP particles on the self-healing ability of mortar cracks was revealed by crack microscopic observation tests and microscopic experiments. (2) The effect of different self-healing agent amounts on the self-healing ability of mortar cracks has been studied. (3) The effects of EP particles and self-healing agents on healing different initial widths were elucidated by crack microscopic observation tests.

This study produced epoxy-filled urea-formaldehyde (UF) microcapsules (MCs) and T-403 amine MCs using the in situ technique. The Taguchi method was used to determine the effects of the control factors (temperature, stirring speed, core-shell ratio and surfactant concentration) affecting MCs’ core diameter and core content and optimizing their optimum levels with a single criterion. Optimum control factor levels, which simultaneously provide maximum core diameter and core content of MCs, were determined by the PROMETHEE-GAIA multi-criteria optimization method. In addition, the optimized MC yield was analyzed by thermal camera images and compression test.

Microcracks in materials used for aerospace vehicles and automotive parts cause serious problems, so research on self-healing in materials science becomes critical. The damages caused by micro-cracks need to heal themselves quickly. The study has three aims: (1) production of self-healing MCs, mechanical and chemical characterization of produced MCs, (2) single-criteria and multi-criteria optimization of parameters providing maximum MC core diameter and core content, (3) investigation of self-healing property of produced MCs and evaluation. Firstly, MCs were produced to achieve these goals.

The optimized micro cures are buried in the epoxy matrix at different concentrations. Thermal camera images after damage indicate the presence of healing. An epoxy-amine MC consisting of a 10% by weight filled aluminum sandwich panel was prepared and subjected to a quasi-static compression test. It was determined that there is a strong bond between the UF shell and the epoxy resin.

The optimization of production factors has been realized to produce the most efficient MCs that heal using less expensive and more accessible methods.

This paper aims to exploit shape-memory polymers as self-healable materials. The underlying mechanism involved the thermal transitions as well as the enrichment of the healing reagents and the closure of the crack surfaces due to shape recovery. The multi-stimuli-triggered shape memory composite was capable of self-healing under not only direct thermal but also electrical stimulations.

The shape memory epoxy polymer composites comprising the AgNWs and poly (ε-caprolactone) were fabricated by dry transfer process. The morphologies of the composites were investigated by the optical microscope and scanning electron microscopy (SEM). The electrical conduction and the Joule heating effect were measured. Furthermore, the healing efficiency under the different stimuli was calculated, whose dependence on the compositions was also discussed.

The AgNWs network maintained most of the pathways for the electrons transportation after the dry transfer process, leading to a superior conduction and flexibility. Consequently, the composites could trigger the healing within several minutes, as applied with relatively low voltages. It was found that the composites having more the AgNWs content had better electrically triggered performance, while 50 per cent poly (ε-caprolactone) content endowed the materials with max healing efficiency under thermal or electrical stimuli.

The findings may greatly benefit the application of the intelligent polymers in the fields of the multifunctional flexible electronics.

Most studies have by far emphasized on the direct thermal triggered cases. Herein, a novel, flexible and conductive shape memory-based composite, which was capable of self-healing under the thermal or electrical stimulations, has been proposed.

This study aims to investigate the indigenous healing space in South Africa, by zooming in on the confusions that are faced by young people in the country. These muddles are a result of the country’s colonial and apartheid history which left the population divided between the Western and African philosophies when it comes to health among other things. The recent technological developments which are embraced by some of the healers exposed the space to exploitation by criminal elements.

This qualitative study used content analysis and interviews to gather data.

The results suggest that the indigenous healing space in South Africa is poorly regulated and a fertile breeding ground for criminals. As a result, it is not easy to distinguish between genuine healers and bogus ones. The technological advancement, especially social media, has exposed the space to further exploitation by criminal elements.

This study paints a picture of the indigenous healing space in the age of technology in South Africa. This study further explains challenges faced by South Africans in navigating philosophical challenges influenced by their colonial past.