Multiple assembly strategies for silica aerogel-fiber combinations – a review

Silica aerogels have a unique structure that makes them promising materials for variable applications. However, they are brittle due to weak inter-particle necks, and also expensive. Combining aerogel with fibers can not only enhance the mechanical/insulation properties, but also reduce dust release, and ease practical application. The majority of review articles in this field have been on the aerogel/textile systems' application or on textile impregnation in silica sol utilizing the sol–gel technique, with a few papers also addressing the use of aerogel as filler. This review for the first time highlights all strategies to assemble silica aerogel with textile materials. For sol–gel approaches, the fibers can be impregnated in a silica precursor sol to form the aerogel in situ between the fibers, but the sol itself can also be spun into aerogel fibers. Other strategies employ pre-formed silica aerogel, mixed in polymer or solvent matrices/slurries, to form aerogel injected blankets, aerogel-filled material coated fibers, and aerogel-filled composite fibers. Aerogel particles-filled textile packages have also been proposed. The emerging activities on simulations of aerogel-fiber combinations are reviewed. The advantages/disadvantages of various approaches are evaluated, and the current market situation and an outlook for the future of the field are summarized

Development of a hybrid method of social force modeling and discrete event simulation to optimize productivity of construction

Optimizing productivity of construction has always been a challenge for project managers and planners. In previous studies, it has been pointed out that productivity is directly related to the number of workers unless the excessive number of workers in the workshop causes congestion. Discrete event simulation is one of the mathematical modeling methods used by researchers to study productivity in construction. Discrete event simulation models the operations considering the flow of resources and the state of entities within the system. In this model, the entities are passive elements that are processed during the work process. Due to the nature of the entities in a discrete event simulation model, it is not possible to investigate the effect of physical interaction of individuals on productivity using this method alone. Social Force Modeling has a great ability to model the movement of people and physical interaction between people and the environment. This study tries to investigate the direct impact of manpower on productivity by modeling the work process and the effect of physical interactions of workers due to the increase in the number of workers and workshop spatial constraints. For this purpose, a hybrid model has been developed that includes a combination of two models. In the first model, the discrete event simulation method is used to simulate the work process. In the second model, the movement and physical interaction of workers are modeled using the social force modeling method. The proposed hybrid model allows one or more activities to be simulated more accurately. The approach used in this paper is evaluated based on the data from a real project. The results clearly show the reduction in productivity due to overcrowding. The outputs of this work can be used to obtain the optimal number of workers in an activity. The model proposed in this paper gives project managers the chance to have more realistic simulations of work processes

A Review on Melt-Spun Biodegradable Fibers

The growing awareness of environmental issues and the pursuit of sustainable materials have sparked a substantial surge in research focused on biodegradable materials, including fibers. Within a spectrum of fabrication techniques, melt-spinning has emerged as an eco-friendly and scalable method for making fibers from biodegradable plastics (preferably bio-based), intended for various applications. This paper provides a comprehensive overview of the advancements in the realm of melt-spun biodegradable fibers. It delves into global concerns related to micro- and nanoplastics (MNPs) and introduces the concept of biodegradable fibers. The literature review on melt-spun biodegradable monofilaments and multifilaments unveils a diverse range of polymers and copolymers that have been subjected to testing and characterization for their processing capabilities and the performance of the resultant fibers, particularly from mechanical, thermal, and biodegradation perspectives. The paper discusses the impact of different factors such as polymer structure, processing parameters, and environmental conditions on the ultimate properties, encompassing spinnability, mechanical and thermal performance, and biodegradation, with schematic correlations provided. Additionally, the manuscript touches upon applications in sectors such as clothing, technical textiles, agriculture, biomedical applications, and environmental remediation. It also spotlights the challenges encountered in the commercialization of these fibers, addresses potential solutions, and outlines future prospects. Finally, by shedding light on the latest developments, challenges, and opportunities in the field, this review endeavors to stimulate further innovation and adoption of biodegradable fibers. It seeks to unlock their potential and contribute to the realization of a more environmentally conscious society

Core‐shell nanofibers for developing self‐healing materials: Recent progress and future directions

The knowledge of self‐healing was developed to ensure more durable and reliable engineering materials. Healing agent encapsulation has shown to be one of the most promising approaches in self‐healing technology. The healing agents were encapsulated within micro/nanocapsules, micro/nanofibers, and vascular‐based networks. Among the methods, using core‐shell nanofibers showed a compromising potential for the development of self‐healing nanofibers with the minimum drawbacks and limitations. The aim of the present paper is to report the recent contributions on the recent progress of self‐healing materials using core‐shell nanofibers to provide insights for the further development of self‐healing polymeric materials both in academic research and scalable fabrication of polymeric parts in the industries