Electrospun Polymer Nanofibers for Technology Applications: A Short Review

Nanofibers are a type of nanomaterial with a diameter ranging from ten to a few hundred nanometers with a high surface-to-volume ratio and porosity. They can build a network of high-porosity material with excellent connectivity within the pores, making them a preferred option for numerous applications. This review explores nanofibers from the synthesis techniques to fabricate nanofibers, with an emphasis on the technological applications of nanofibers like water and air filtration, photovoltaics, batteries and fuel cells, gas sensing, photocatalysis, and biomedical applications like wound dressing and drug delivery. The nanofiber production market has an expected compound annual growth rate (CAGR) of 6% and should reach around 26 million US $ in 2026. The limitations and potential opportunities for large-scale applications of nano-fibrous membranes are also discussed. We expect this review could provide enriched information to better understand Electrospun Polymer Nanofiber Technology and recent advances in this field. © 2023 Bentham Science Publishers.

Recent development in antiviral surfaces: Impact of topography and environmental conditions.

The transmission of viruses is largely dependent on contact with contaminated virus-laden communal surfaces. While frequent surface disinfection and antiviral coating techniques are put forth by researchers as a plan of action to tackle transmission in dire situations like the Covid-19 pandemic caused by SARS-CoV-2 virus, these procedures are often laborious, time-consuming, cost-intensive, and toxic. Hence, surface topography-mediated antiviral surfaces have been gaining more attention in recent times. Although bioinspired hydrophobic antibacterial nanopatterned surfaces mimicking the natural sources is a very prevalent and successful strategy, the antiviral prospect of these surfaces is yet to be explored. Few recent studies have explored the potential of nanopatterned antiviral surfaces. In this review, we highlighted surface properties that have an impact on virus attachment and persistence, particularly focusing and emphasizing on the prospect of the nanotextured surface with enhanced properties to be used as antiviral surface. In addition, recent developments in surface nanopatterning techniques depending on the nano-scaled dimensions have been discussed. The impacts of environments and surface topology on virus inactivation have also been reviewed.

Influence of biochar on improving hydrological and nutrient status of two decomposed soils for yield of medicinal plant - Pinellia ternata

The root tuber of Pinellia ternata has been used as a traditional therapeutic herbal medicine. It is reported to impart beneficial attributes in recovering COVID-19 patients. To meet an increasing demand of P. ternata, this study is intended to investigate the effects of biochar on the soil hydrological and agronomic properties of two decomposed soils (i.e., completely decomposed granite (CDG) and lateritic soil) for the growth of P. ternata. The plant was grown in instrumented pots with different biochar application rate (0%, 3% and 5%) for a period of three months. Peanut shell biochar inclusion in both soils resulted in reduction of soil hydraulic conductivity and increase in soil water retention capacity. These alterations in hydrological properties were attributed to measured change in total porosity, biochar intra pore and hydrophilic functional groups. The macro-nutrient (i.e., N, P, K, Ca, and Mg) concentration of both soils increased substantially, while the pH and cation exchange capacity levels in the amended soils were altered to facilitate optimum growth of P. ternata. The tuber biomass in biochar amended CDG at all amendment rate increases by up to 70%. In case of lateritic soil, the tuber biomass increased by 23% at only 5% biochar application rate. All treatments satisfied the minimum succinic acid concentration required as per pharmacopoeia standard index. The lower tuber biomass exhibits a higher succinic acid concentration regardless of the soil type used to grow P. ternata. The biochar improved the yield and quality of P. ternata in both soils.

Effect of Replacing Feldspar by Philippine Black Cinder on the Development of Low-Porosity Red Stoneware

Stoneware is a ceramic material with low porosity and high mechanical properties, such as the modulus of rupture. It is essentially made of clay, feldspar and quartz and is sintered to create a mixture of glass and crystalline phases. With the projected growth rate of the global ceramics market size and the country's development plan for 2023–2028, it is imperative that alternative raw materials for the manufacture of ceramic products be sourced so that the importation of these materials, such as feldspar, be minimized, if not eliminated. Cinder in the Philippines is mainly used as a filling material in pavements and residential areas. In this study, this resource is utilized as partial and full replacement of feldspar in a typical ternary diagram for stoneware production. Bars were formed from different formulations by the slip casting method and were sintered at 1200 °C. Physical and mechanical properties of the bars, such as shrinkage, loss on ignition, water absorption, apparent porosity and modulus of rupture were determined. Thermo-physical analyses were also carried out on the raw materials and on formulated powders. Meeting the requirements of the various quality standards for ceramics, the partial replacement of feldspar with black cinder (LF, LFBQ and LFBH) is feasible for wall and roof applications while full replacement of feldspar with black cinder (LB) is suitable for wider use as wall, floor, vitrified, industrial and roof tiles.

Mass transfer effects on mucus fluid in the presence of chemical reaction

The mucus fluid vehicle is impacted by the synthetic response that changes the physical science of liquid due to the thickness of the bodily fluid. Additionally, various issues in the respiratory system might happen because of bodily fluid adequacy. A central point of transportation of immunizations to forestall COVID-19 is the concentration level expected during movement, stockpiling, and dispersion. The current review stated that mucus fluid transportation is restrained through magnetic force originating due to heat variation. Permeable channel over respiratory disease and chemicals due to mass reaction–diffusion variation. The bodily fluid development is surveyed by the force, energy, and diffusion condition influence of body powers because of attractive field, source of heat cause of thermal conduction, resistance due to disease chemical reaction cause of concentration profile. The nonlinear arrangement of incomplete differential conditions is addressed by the Laplace transform technique, and MATLAB programming outcomes are initiated for momentum, temperature, and diffusion fields and inferred that the bodily fluid stream decelerates due to magnetic force. The skin friction, Nusselt number, Sherwood number, and the microorganism's thickness are assessed and explained exhaustively. Furthermore, microorganisms are occupied in different elements to survey the mucus fluid mechanism. © 2022

Development of reusable cloth mask with nanoparticle filtration efficiency greater than 95%

ABSRACT: After the rapid spread of SARS-Cov-2 virus, the use of masks was suggested by the world health organization (WHO) to reduce the virus transmission, whose primary mode of transmission was suggested to be through respiratory droplets. The recommended face coverings were single use surgical and respirator masks made of non-woven materials. With the increased demand for masks worldwide, the environmental impacts of mask disposal and the pollution caused by microplastic fibers of the non-woven materials were presented. This challenge necessitates the need for the development of a novel reusable mask reducing the environmental effects, while providing the necessary personal protective properties. Based on the ASTM F2299 standard test method, the performance, i.e., particle-size dependent filtration efficiency and pressure drop were studied for 20 samples with multilayer knit fabrics of natural and synthetic fibers (inner layer of pure cotton, cotton-nylon and cotton-polyester, middle layer of Lycra, and outer layer of superhydrophobic polyester). The results show that all the samples had an efficiency of >94% and 87–99% for large (250 (Formula presented.) –1 (Formula presented.) m) and small (100–250 nm) particles, respectively. The best performing structure has a material composition of 41% superhydrophobic polyester, 26% natural cotton, 24% nylon and 9% Lycra. The filtration efficiency, pressure drop, and quality factor for this sample are 97.8% (for 100 nm particles), 4.04 mmH2O/cm2 and 4.77 kPa−1, respectively. It was also demonstrated that the developed mask maintains its performance after 50 wash/dry cycles, verifying its reusability. It should be noted that charge neutralizer was not used in the experimental setup of this study which might have led to enhanced results for the filtration efficiency of small (100–250 nm) particles due to the dominance of electrostatic attraction. However, several samples were tested by the third-party company who uses a certified testing equipment based on ASTM F2299, and similar results were obtained. Copyright © 2022 American Association for Aerosol Research.

A review on production and application of activated carbon from discarded plastics in the context of ‘waste treats waste'

In the post-COVID scenario, the annual increase in plastic waste has taken an upsurge due to the disposal of plastic masks, gloves and other protective equipment. To reduce the plastic load ending up in landfills and oceans or dumped at roadsides, the potential of using plastic polymers in different sectors has been investigated over the years leading to their potential application in pavement laying, concrete industry, fuel generation and production of carbon-based compounds among which activated carbons (AC) is a prime example. As one of the most recommended adsorbents for removing contaminants from water and adsorbing greenhouse gases, AC creates a potential sector for using discarded plastic to further treat pollutants and approach closer to a circular economy for plastics. This paper analyses the production process, the effect of production parameters on AC characteristics and properties that aid in adsorption. The interdependence of these factors determines the surface area, porosity, relative micropore and mesopore volume, thereby defining the utility for removing contaminant molecules of a particular size. Furthermore, this work discusses the application of AC along with a summary of the earlier works leading to the existing gaps in the research area. Production costs, formation of by-products including toxic substances and adsorbate selectivity are the major issues that have restricted the commercial application of this process towards its practical use. Research aimed at valorization of plastic waste into ACs would minimize the solid waste burden, along with treating other pollutants. © 2022 Elsevier Ltd

Efficient selective adsorption of cytokine IL-6 and other middle-macromolecular toxins in the serum of uremia patients with specially designed porous hollow carbon spheres

[Display omitted] • Porous hollow carbon spheres (HCSs) with adjustable size and pore width distribution were synthesized. • The clearance rate of HCSs to interleukin 6 (IL-6) in PBS buffer solution was up to 99.8%. • HCSs had a high adsorption rate and removal efficiency for PTH, β 2 -MG, IL-6 and TNF-α in the serum of uremic patients. • The selective adsorption of middle-macromolecular toxins or cytokines was achieved by regulating the pore structure of HCSs. Abnormally elevated middle-macromolecular toxins such as interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF- α) in human blood are fatal precipitating factors for patients suffered from immune-related diseases, especially for uremia and COVID-19 critical patients, while the effective clearance of them has always been problematic in clinic. In this work, porous hollow carbon spheres (HCSs) with different size and pore structure has been successfully prepared. The removal efficiency for IL-6 in PBS solution is about 99.8 %, even in the serum of uremic patients, HCSs could remove 94.75 % and 98.33 % of parathyroid hormone (PTH) and β 2 -microglobulin (β 2 -MG) efficiently within 5–10 min, and particularly, the adsorption of IL-6 and TNF- α is 17.6 and 11.4 times higher over that of the existing commercial hemoperfusion adsorbents. The adsorption balance can be achieved in 60 min, which would greatly shorten the current clinical treatment duration. Moreover, HCSs with different pore structure exhibit distinct adsorption selectivity for IL-6 and TNF- α, which is of special significance for modifying the middle-macromolecular cytokine level in the complicated human blood environment. [ FROM AUTHOR]

The impact of disposable mask waste pollution in peat soil

The abundance of plastic waste in Indonesia has increased due to the contribution of disposable masks waste during the COVID-19 pandemic. The improper waste management causes the habit of dumping waste in the soil system to still frequently occur. The secondary microplastics from disposable mask waste has the potential to damage soil quality and soil capillary water. Therefore, this study was conducted with the aim of understanding the effects of disposable mask waste in peat soil. The research was conducted by setting up 3 reactors containing peat soil with disposable mask waste buried in it and some plants being grown on it. For 45 days, observations and samples were taken, both filtrate water and soil for analysis. The analysis results showed significant changes in soil properties with changes in the concentration of inorganic matter, organic matter, porosity, bulk density, and water content. Further research needs to be done to see the effects of disposable mask waste in the soil system in real conditions where several confounding variables cannot be controlled.

Mass transfer effects on mucus fluid in the presence of chemical reaction

The mucus fluid vehicle is impacted by the synthetic response that changes the physical science of liquid due to the thickness of the bodily fluid. Additionally, various issues in the respiratory system might happen because of bodily fluid adequacy. A central point of transportation of immunizations to forestall COVID-19 is the concentration level expected during movement, stockpiling, and dispersion. The current review stated that mucus fluid transportation is restrained through magnetic force originating due to heat variation. Permeable channel over respiratory disease and chemicals due to mass reaction–diffusion variation. The bodily fluid development is surveyed by the force, energy, and diffusion condition influence of body powers because of attractive field, source of heat cause of thermal conduction, resistance due to disease chemical reaction cause of concentration profile. The nonlinear arrangement of incomplete differential conditions is addressed by the Laplace transform technique, and MATLAB programming outcomes are initiated for momentum, temperature, and diffusion fields and inferred that the bodily fluid stream decelerates due to magnetic force. The skin friction, Nusselt number, Sherwood number, and the microorganism’s thickness are assessed and explained exhaustively. Furthermore, microorganisms are occupied in different elements to survey the mucus fluid mechanism.

New experimental low-cost nanoscience technology for formulation of silver nanoparticles-activated carbon composite as a promising antiviral, biocide, and efficient catalyst

A simple low-cost one-pot photodeposition synthesis with no hazardous reactants or products is used to make silver nanoparticles-activated carbon composite (SNPs@AC). The SNPs are homogenously and photodeposited and absorbed into the activated carbon matrix. Both SNPs and SNPs@AC composite have particle sizes around 10 nm and 100 nm, respectively. The SNPs@AC composite showed good antiviral activity to VERO (ATCC ccl-81) cells. Zeta potential of SNPs@AC composite is −25 mV, showing that this colloidal system is electrically stable and resistant to coagulation. For many Gram-positive and Gram-negative bacteria, the SNPs@AC composite demonstrated strong antibacterial efficacy. The SNPs@AC composite has 75.72 percent anti-inflammatory effect at concentration 500 µg/mL. This composite has a maximum non-toxic concentration (MNTC) of 78.125 g/mL, which corresponds to antiviral activity of up to 96.7 percent against hepatitis A. virus (HAV). It is suggested as a candidate for pharmaceutical formulations, such as integration into the manufacture of N95 masks for COVID-19 infection protection. Concentration 160 μg/mL SNPs@AC composite has antioxidant activity 42.74% percent. The SNPs@AC composite exhibited selective catalytic activity for the organosynthesis hydrazination reaction of 4-chloro-3, 5-di-nitro-benzo-triflouride, giving 1-hydroxy-4-nitro-6-trifluoro-methyl benzotriazole, a common antiviral drug for severe acute respiratory syndrome (SARS). SNPs@composite's well-defined pores provide suitable active sites for binding reactants: 4-Cl-3, 5-di-NO2-benzotriflouride, and hydrazine, which react to create 1-hydroxy-4-nitro-6-trifluoromethyl benzotriazole, which diffuses into solution away from the catalyst surface, leaving the catalyst surface unaffected.

A blueprint for well-designed, high-performing cloth masks that can outperform a 3-layered surgical mask

Introduction: During COVID-19, due to the worldwide shortages of medical masks, homemade cloth masks became a mainstay of the pandemic. The CDC and WHO recommend the use of homemade cloth masks. However, there is insufficient evidence on the performance: respiratory droplet blocking ability, water-resistant capacity, breathability, and washability of commonly used fabrics to design high-performing cloth masks that can outperform medical masks. Material and Methods: We conducted a series of experiments on aerosol blocking (using healthy volunteers sneeze, image-based flow measurement technique), water-resistant, breathability, and washability to evaluate all dimensions of protection of 17 different commonly available fabrics and their layered combinations. Results: The research provides a blueprint for the optimal design of a high-performing cloth mask that can outperform a 3-layered surgical mask. A minimum of 3 layers is recommended to provide the performance of surgical masks. A combination of cotton/linen for the inner layer, blends for the middle–layer, and polyester/nylon for the outer–layer. The average thread count (threads contained in one square inch) should be greater than 200, and the porosity (percent of pores in a fabric) should be less than 2 %. Increasing the number of layers increases the droplet blocking efficiency by approximately 20 times per additional fabric layer. Machine washing at 60 °C did not affect the performance of cloth masks. Conclusions: These results and visualizations can assist people in preparing effective homemade cloth masks during the ongoing COVID-19 pandemic and future epidemics.

Use of dilatometer to screen refractory raw materials

Sudden shortage of a particular raw material due to freight disruptions, competitive market, and COVID restrictions have frequently forced the refractory industry to rapidly develop alternative formulations using available low‐cost materials. These alternative ingredients might cursorily appear to have similar total impurity content, but the presence of certain impurity combinations depending on the refractory type can produce more fluid liquid phase at high temperature, thereby drastically reducing hot strength. Undetected by the commonly used X‐ray fluorescence (XRF) analysis, the low‐cost material might differ in mineral‐phase content, whose phase transformations during firing might create excessive expansion producing warpage of the refractory along with a high porosity reducing strength and corrosion resistance. Finally, those cheap raw materials might have similar sieve analysis to that of the standard ingredient but might have much lower tapped density, which would introduce detrimental porosity into the resulting refractory. Hence, time‐consuming trials are often performed. Dilatometer studies on pressed or cast samples in a single test can identify reaction temperatures of spinel or mullite formation, which expand during firing, along with the amount of expansion and exact times at which firing needs to be done. It can also compare relative shrinkage due to liquid‐phase formation among impure raw materials like recycled grogs or low‐grade ores. Finally, dilatometric step scan is shown as a fast technique to prepare in‐house, low‐cost reactive spinel powder, which can also work for mullite.

The effects of face mask specifications on work of breathing and particle filtration efficiency.

The outbreak of the ongoing coronavirus disease 2019 (COVID-19) pandemic has led to the recommended routine use of face masks to reduce exposure risk. In this study, the increase in work of breathing (WOB) imposed by face masks is theoretically studied for both normals and patients with obstructive and restrictive lung diseases at different levels of activity. The results show a significant increase in WOB due to face masks, which is more severe in higher activity levels. The added WOB is considerable during physical activity and may be intolerable for patients with preexisting lung disease and may contribute to inspiratory muscle fatigue and dyspnea. Moreover, in this study, the effects of the physical properties of a fibrous medium, including thickness, porosity, and fiber diameter, are analyzed on the particle filtration efficiency (PFE) and the added WOB. The relations between the physical properties of the fibrous medium and the added WOB and the PFE are shown on some contour plots as a quick and simple tool to select the desired physical properties for a single layer filter to ensure that the added WOB is comfortable while the PFE is sufficiently high.

Sponge particulates for biomedical applications: Biofunctionalization, multi-drug shielding, and theranostic applications.

Sponge particulates have attracted enormous attention in biomedical applications for superior properties, including large porosity, elastic deformation, capillary action, and three-dimensional (3D) reaction environment. Especially, the tiny porous structures make sponge particulates a promising platform for drug delivery, tissue engineering, anti-infection, and wound healing by providing abundant reservoirs of broad surface and internal network for cargo shielding and shuttling. To control the sponge-like morphology and improve the diversity of drug loading, some optimized preparation techniques of sponge particulates have been developed, contributing to the simplified preparation process and improved production reproducibility. Bio-functionalized strategies, including target modification, cell membrane camouflage, and hydrogel of sponge particulates have been applied to modulate the properties, improve the performance, and extend the applications. In this review, we highlight the unique physical properties and functions, current manufacturing techniques, and an overview of spongy particulates in biomedical applications, especially in inhibition of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infectivity. Moreover, the current challenges and prospects of sponge particulates are discussed rationally, providing an insight into developing vibrant fields of sponge particulates-based biomedicine.