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The purpose of this paper is to investigate the effect of hexagonal boron nitride (h-BN) and poly (phenyl p-hydroxybenzoate) (PHBA) on improving the torsional tribological behavior of polytetrafluoroethylene (PTFE).

This paper investigates the torsional tribological behavior of PTFE composites filled with h-BN and PHBA under different angular displacements with a plane-on-plane torsional friction tester. The worn surface of PTFE composites was investigated by using a scanning electron microscope.

The shape of T–Θ curves of PTFE composites was influenced by both content fillers and torsional angule. The material with a higher coefficient of sliding friction exhibited the larger torsional angle under which the torsional regime transited from a partial slip to a gross slip. PTFE composites filled with 20 weight per cent PHBA and 10 weight per cent h-BN showed the best anti-wear properties. The specific wear rate of composites exhibits a negative correlation with material hardness. The wear volume loss presents a positive correlation with friction dissipation energy. The specific wear rate of all composites decreased with increasing torsional angle. The dominant wear mechanism of pure PTFE was adhesive wear. The slight plastic flow and plowing occurred on the worn surfaces of PTFE composites because of the higher hardness of composites and the lubrication of h-BN particles with layer crystal structure.

This paper put forward a kind of PTFE composite with low torsional wear rate, which can be used in the sliding slewing bearing or the center plate of a bogie.

This article examines the inaction, silencing and ignorance in ex ante disasters whilst conducting a case study analysis of the Izmir/Samos earthquake, a 6.6 Mw (moment magnitude) earthquake that occurred at a depth of 14.9 km from the ground on 30 October 2020 at 2:51 PM. The 8-floor Riza Bey Apartment in Bayrakli/Izmir was demolished in the earthquake approximately 100 km from the epicenter. After the earthquake, several lawsuits started to conduct investigations on an apartment basis. Focusing on the causes of disasters in engaging with adoptive thinking in disasters, the current article posits the following research question: what are the ex ante socio-technical dynamics and causes of fatality in disasters?

The methodological tools and advice related to disaster prevention in ex ante disasters originate from the actor network theory (ANT). Although ANT probes complex and dynamic multiplicities in disaster prevention management, this may be unsatisfactory for conceptualizing and operationalizing a disaster, as it is heavily reliant on discerning between humans and non-humans. Data were gathered (February 2021–February 2022) from 15 face-to-face interviews, 2 phone interviews, official documents, archival records, open-sourced public interviews, political speeches, newspaper articles, public reports, expert reports stories, videos, legal transcriptions and photographs. Additionally, data were gathered from the commission minutes officially published on the government website.

This article revealed the confusion of authority between the local and central governments and the gap between institutions and citizens in understanding and implementing the disaster prevention laws and regulations. It found that the causes of disasters beyond any dichotomies, such as surface versus site and ground versus grounded, rely not only on the technical roles of disaster prevention but also the non-technical roles assigned to it.

Since the lawsuit has been in continuation, the process is still alive, and data gathering is limited to the litigation conditions of public servants in terms of sharing information. Since many of the flat owners died, it is difficult to access information on the apartment meetings to learn more about the resistance of flat owners against urban transformation and the possibility of ignoring or hiding the risk assessment report.

Disaster prevention is such a complex process which generates complex adaptation mechanisms (physical, behavioral, biological, cognitive through training, learning and experiencing). Also, there is a need to understand the scale of adaptive behavior and its function to improve adoptive mechanisms. With a transdisciplinary focus, each discipline needs to embrace one another's calculation and calculative practices while they measure, observe, analyze and implement risk and uncertainties.

It is hard to prevent disasters without knowing the flow of root relations between actors and elements that are in movement with different directions, forms and motions. These unbalanced, uneven and endless root relationships between actors' movements create a constant state of tension of organizing, recording, auditing, quantifying, computing, mapping (geology, Earth information system and micro-zonation), budgeting, bookkeeping, measuring, performance, regulating, controlling, monitoring and auditing with all the numbers and data.

There is a gap in the literature in terms of the interaction between accounts and institutions in ex ante disaster.