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In this paper the aim is that Aramid/alginate blended nonwoven fabrics were prepared, and the flame retardancy of the blended nonwoven fabrics was studied by thermogravimetric analysis, vertical flame test, limiting oxygen index (LOI) and cone calorimeter test.

The advantages of different fibers can be combined by blending, and the defects may be remedied. The study investigates whether incorporating alginate fibers into aramid fibers can enhance the flame retardancy and reduce the smoke production of prepared aramid/alginate blended nonwoven fabrics.

Thermogravimetric analysis indicated that alginate fibers could effectively inhibit the combustion performance of aramid fibers at a higher temperature zone, leaving more residual chars for heat isolation. And vertical flame test, LOI and cone calorimeter test testified that the incorporation of alginate fibers improved the flame retardancy and fire behaviors. When the ratio of alginate fibers for aramid/alginate blended nonwoven fabrics reached 80%, the incorporation of alginate fibers could notably decreased peak-heat release rate (54%), total heat release (THR) (29%), peak-smoke production rate (93%) and total smoke production (86%). What is more, the lower smoke production rate and lower THR of the blends vastly reduced the risk of secondary injury in fires.

This study proposes to inhibit the flue gas release of aramid fiber and enhance the flame retardant by mixing with alginate fiber, and proposes that alginate fiber can be used as a biological smoke inhibitor, as well as a flame retardant for aramid fiber.

Alginate fiber with a breaking tenacity of up to 2.32 cN/dtex is prepared by spinning a sodium alginate solution in a coagulating solution of CaCl₂ aqueous solution followed by multi-roller drawing. Preparation parameters such as sodium alginate concentration, coagulant concentration and coagulation temperature, which affect the fiber tenacity, are investigated with an orthogonal test design, and the best spinning process is found with a coagulating 5% sodium alginate solution in 4% CaCl₂ at 40°C. The morphology, degree of crystallinity, thermal stability and the combustion performance of this alginate fiber are investigated by scanning electron microscopy (SEM), infrared (IR), X-ray diffraction (XRD), Thermo gravimetric Analysis (TGA) and Cone Calorimeter. Using the centrifugal dewatering method, the absorption capacity of this alginate fiber is determined, and has a capacity of 13.01 grams of man-made blood per gram. The test results show that fibers have an irregular cross-section without a thicker cortex and uniform longitudinal surface with grooves. The combustion property results demonstrate that the fiber has a self-flameretarding property.

The purpose of this study reported in this paper was to find the correct Mt/M₈ and Dt/a² data lists of Hill Formula. This paper enumerates several kinds of Hill formula data lists presented in different literatures, and the authors hope to draw the correct conclusion.

The eight different forms collected in the research project were compared. The mathematician was asked to give a suggestion from a professional point of view and to arrive at a conclusion.

In all eight cases, the third, the eighth and seventh cases are consistent and are considered reasonable and correct.

First-hand information was not used because of unavailability of the earliest published version of the Hill formula.

It is helpful to the correct application of Hill formula and the calculation of diffusion coefficient. It is also valuable to the study of dyeing kinetics.

The research helps to reduce and avoid the confusion in the application of Hill formula in dyeing kinetics research.

This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO₂ and its radiative cooling effect on firefighting clothing without environmental pollution.

SA/SiO₂ aerogel with refractory heat insulation and enhanced radiative cooling performance was fabricated by freeze-drying method, which can be used in firefighting clothing. The microstructure, chemical composition, thermal stability, and thermal emissivity were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analyzer and infrared emissivity measurement instrument. The radiative cooling effect of aerogel was studied using thermal infrared imager and thermocouple.

When the addition of SiO₂ is 25% of SA, the prepared aerogel has excellent heat insulation and a high radiative cooling effect. Under a clear sky, the temperature of SA/SiO₂ aerogel is 9.4°C lower than that of pure SA aerogel and 22.1°C lower than that of the simulated environment. In addition, aerogel has more exceptional heat insulation effect than other common fabrics in the heat insulation performance test.

SA/SiO₂ aerogel has passive radiative cooling function, which can efficaciously economize global energy, and it is paramount to environment-friendly cooling.

This method could pave the way for high-performance cooling materials designed for firefighting clothing to keep maintain the wearing comfort of firefighters.

SA/SiO₂ aerogel used in firefighting clothing can release heat to the low-temperature outer space in the form of thermal radiation to achieve its own cooling purpose, without additional energy supply.

Wound healing is a dynamic process that relies on coordinated signaling molecules to succeed. Silk has proven to be a promising biomaterial for the development of a novel product. The purpose of the study is development of silk films, augmented functionality can be provided to silk by means of loading honey and recombinant human epidermal growth factor (rhEGF).

In this research work, the authors set out to explore possibilities of silk-based biomedical device development with particular attention to different fabrication strategies that can be leveraged for this purpose. They have produced a novel silk-based drug delivery material, in the form of silk films. Scanning electronic microscope was used to observe the morphology and the highly specific surface area. The structure was studied by Fourier-transform infrared spectroscopy. This methodology is accomplished using in vivo study data using Wister albonia rats.

The developed films also provided a significant higher healing rate in vivo, with well-formed epidermis with faster granulation tissue formation when compared to the controls. Biodegradable polymeric materials based on blending aqueous dispersions of natural polymer sodium alginate, Chitosan and rhEGF complex, which allow controlled antiseptic release, are presented.

These results suggest that silk-based controlled release of Chitosan-rhEGF may serve as a new therapy to accelerate healing of burn wounds.

Additive manufacturing (AM) or solid freeform fabrication (SFF) technique is extensively used to produce intrinsic 3D structures with high accuracy. Its significant contributions in the field of tissue engineering (TE) have significantly increased in the recent years. TE is used to regenerate or repair impaired tissues which are caused by trauma, disease and injury in human body. There are a number of novel materials such as polymers, ceramics and composites, which possess immense potential for production of scaffolds. However, the major challenge is in developing those bioactive and patient-specific scaffolds, which have a required controlled design like pore architecture with good interconnectivity, optimized porosity and microstructure. Such design not only supports cell proliferation but also promotes good adhesion and differentiation. However, the traditional techniques fail to fulfill all the required specific properties in tissue scaffold. The purpose of this study is to report the review on AM techniques for the fabrication of TE scaffolds.

The present review paper provides a detailed analysis of the widely used AM techniques to construct tissue scaffolds using stereolithography (SLA), selective laser sintering (SLS), fused deposition modeling (FDM), binder jetting (BJ) and advanced or hybrid additive manufacturing methods.

Subsequently, this study also focuses on understanding the concepts of TE scaffolds and their characteristics, working principle of scaffolds fabrication process. Besides this, mechanical properties, characteristics of microstructure, in vitro and in vivo analysis of the fabricated scaffolds have also been discussed in detail.

The review paper highlights the way forward in the area of additive manufacturing applications in TE field by following a systematic review methodology.

Intense interest has been shown in creating new and effective biocide agents as a result of changes in bacterial isolates, bacterial susceptibility to antibiotics, an increase in patients with burns and wounds and the difficulty of treating infections and antimicrobial resistance. Woven, nonwoven and knitted materials are used to make dressings; however, nonwoven dressings are becoming more popular because of their softness and high absorption capacity. Additionally, textiles have excellent geometrical, physical and mechanical features including three-dimensional structure availability, air, vapor and liquid permeability, strength, extensibility, flexibility and diversity of fiber length, fineness and cross-sectional shapes. It is necessary to treat every burn according to international protocol and along with it has to focus on particular problems of patients and the best possible results.

The objective of this paper is to conduct a thorough examination of research pertaining to the utilization of textiles, as well as alternative materials and innovative techniques, in the context of burn wound dressings. Through a critical analysis of the findings, this study intends to provide valuable insights that can inform and guide future research endeavors in this field.

In the past years, there have been several dressings such as xeroform petrolatum gauze, silver-impregnated dressings, biological dressings, hydrocolloid dressings, polyurethane film dressings, silicon-coated nylon dressings, dressings for biosynthetic skin substitutes, hydrogel dressings, newly developed dressings, scaffold bandages, Sorbalgon wound dressing, negative pressure therapy, enzymatic debridement and high-pressure water irrigation developed for the fast healing of burn wounds.

This research conducts a thorough analysis of the role of textiles in modern burn wound dressings.

Hydrogels with low viscosities tend to be difficult to use in constructing tissue engineering (TE) scaffolds used to replace or restore damaged tissue, due to the length of time it takes for final gelation to take place resulting in the scaffolds collapsing due to their mechanical instability. However, recent advances in rapid prototyping have allowed for a new technology called bioplotting to be developed, which aims to circumvent these inherent problems. This paper aims to present details of the process.

The paper demonstrates how by using the bioplotting technique complex 3D geometrical scaffolds with accurate feature sizes and good pore definition can be fabriated for use as biological matrices. PEG gels containing the cell‐adhesive RGD peptide sequence were patterned using this method to produce layers of directional microchannels which have a functionalised bioactive surface. Seeding these gels with C2C12 myoblasts showed that the cells responded to the topographical features and aligned themselves along the direction of the channels.

This process allows plotting of various materials into a media bath containing material of similar rheological properties which can be used to both support the structure as it is dispensed and also to initiate cross‐linking of the hydrogel. By controlling concentrations, viscosity and the temperature of both the plotting material and the plotting media, the speed of the hydrogel gelation can be enhanced whilst it is cross‐linking in the media bath. TE scaffolds have been produced using a variety of materials including poly(ethylene glycol) (PEG), gelatin, alginic acid and agarose at various concentrations and viscosities.

This paper describes one of the very few examples of accurate construction of 3D biological microporous matrices using hydrogel material fabricated by the bioplotting technique. This demonstrates that this technique can be used to produce 3D scaffolds which promote tissue regeneration.

Sodium alginate (Na-Alg) is a natural polysaccharide with a rich and renewable production that is widely used in the food, pharmaceutical and daily necessities industries, among other fields. The purpose of this study is to obtain a green and degradable shape memory material, calcium alginate (Ca-Alg) film was prepared and the mechanical properties, the shape memory effect of the film were investigated and confirmed.

The Ca-Alg films were prepared by Na-Alg, calcium chloride (CaCl₂) solution, and flow extension method. Dissolve sodium alginate powder, remove bubbles, pour into petri dish, dry at 60°C, add calcium chloride solution cross-linking and finally dry naturally. The effect of CaCl₂ solution concentration on the mechanical properties of the films were investigated and discussed by universal tensile tester. The shape memory behavior and degradation performance of thin films were verified and studied by the fold-deploy shape memory test and soil embedding method, respectively.

The Ca-Alg films exhibited good mechanical and shape memory properties, with a 72.2% shape memory fixity ratio and a 92.3% shape memory recovery ratio, respectively. For a period of 120 days, the film treated with a 6 wt% CaCl₂ solution degraded at a rate of approximately 53%.

Shape memory polymers (SMPs) as intelligent materials are an important research direction for the development of modern high-tech materials. On the other hand, plastic pollution is a major problem today; as a result, preparing green degradable SMPs is essential.

This study synthesized transparent and degradable shape memory Ca-Alg films using Na-Alg and CaCl₂ solution and the flow extension method.

There are about thirty vitamins and minerals (micronutrients) required by the body (table 1). Although some of these nutrients are required in very small amounts they are, nevertheless, essential for life.