COVID-19 Face Masks as a Long-Term Source of Microplastics in Recycled Urban Green Waste

Following the outbreak of the COVID-19 pandemic in March 2020, many governments recommended or mandated the wearing of fitted face masks to limit the transmission of the SARS-CoV-2 virus via aerosols. Concomitant with the extensive use of non-sterile, surgical-type single-use face masks (SUM) was an increase of such masks, either lost or discarded, in various environmental settings. With their low tensile strength, the spunbond and melt-blown fabrics of the SUM are prone to shredding into small pieces when impacted by lawn cutting equipment. Observations highlight the absence of smaller pieces, which are either wind-dispersed or collected by the mower’s leaf catcher and disposed together with the green waste and then enter the municipal waste stream. As proof-of-concept, experiments using a domestic lawn-mower with different height settings and different grass heights, show that 75% of all pieces of SUM fabric caught in the catcher belonged to sizes below 10 mm2, which under the influence of UV light will decay into microfibers. The implications of SUM generated microplastics are discussed.

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Effect of TiO2 Nanofillers on Mechanical Properties of PVC/ENR/TiO2 Nanocomposites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.911.105 ◽

2014 ◽

Vol 911 ◽

pp. 105-109 ◽

Cited By ~ 1

Author(s):

Nur Azrini Ramlee ◽

C.T. Ratnam ◽

N.H. Alias ◽

T.A. Tengku Mohd

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Uv Light ◽

Research Work ◽

Physical And Mechanical Properties ◽

Shore Hardness ◽

Long Term Stability ◽

Insignificant Difference ◽

Irradiation Dose Rate

Addition of nanoparticles currently in polymer blends has brought tremendous transformation in polymer engineering field. Incorporation of TiO2 nanofillers is believed to enhance the physical and mechanical properties of PVC/ENR blends due to its excellent characteristics including non-toxicity, long term stability and UV light discoloration resistance. The main objective of this research work is to introduce titanium dioxide (TiO2) nanofillers in a range of 0 - 6 phr into polyvinyl chloride (PVC) and epoxidized natural rubber (ENR) blends. Modification on mechanical properties of PVC/ENR blends has successfully been carried via irradiation crosslinking technique. The addition of TiO2 nanofillers has improved the tensile strength and hardness of the nanocomposites. Nevertheless, at higher loading of 6 phr, the results obviously showed an insignificant difference of performances for both tensile strength and shore hardness properties. Upon radiation of 50 kGy, the increase in Ts of the PVC/ENR blends with addition of 4 phr TiO2 was found to be optimum before the Ts value drops with higher exposure to irradiation dose rate. Gel fraction of irradiated PVC/ENR/TiO2 nanocomposites indicates the nanocomposites are crosslinked upon electron beam irradiation. Degree of crosslink was also increased with the addition of 4 phr and 6 phr TiO2.

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ATI 6-2-4-2

Alloy Digest ◽

10.31399/asm.ad.ti0169 ◽

2020 ◽

Vol 69 (8) ◽

Keyword(s):

Tensile Strength ◽

Titanium Alloy ◽

High Temperature ◽

Creep Strength ◽

High Strength ◽

Heat Treating ◽

Good Combination ◽

Long Term Stability ◽

Temperature Performance

Abstract ATI 6-2-4-2 is a near-alpha, high strength, titanium alloy that exhibits a good combination of tensile strength, creep strength, toughness, and long-term stability at temperatures up to 425 °C (800 °F). Silicon up to 0.1% frequently is added to improve the creep resistance of the alloy. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as creep. It also includes information on high temperature performance as well as forming, heat treating, machining, and joining. Filing Code: Ti-169. Producer or Source: ATI.

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Proceedings of the First Curing Coma Campaign NIH Symposium: Challenging the Future of Research for Coma and Disorders of Consciousness

Neurocritical Care ◽

10.1007/s12028-021-01260-x ◽

2021 ◽

Vol 35 (S1) ◽

pp. 4-23

Author(s):

Jan Claassen ◽

Yama Akbari ◽

Sheila Alexander ◽

Mary Kay Bader ◽

Kathleen Bell ◽

...

Keyword(s):

Neurocritical Care ◽

Panel Discussion ◽

Large Datasets ◽

Disorders Of Consciousness ◽

National Institutes Of Health ◽

Proof Of Concept ◽

Research Gaps ◽

Main Research ◽

The World

AbstractComa and disorders of consciousness (DoC) are highly prevalent and constitute a burden for patients, families, and society worldwide. As part of the Curing Coma Campaign, the Neurocritical Care Society partnered with the National Institutes of Health to organize a symposium bringing together experts from all over the world to develop research targets for DoC. The conference was structured along six domains: (1) defining endotype/phenotypes, (2) biomarkers, (3) proof-of-concept clinical trials, (4) neuroprognostication, (5) long-term recovery, and (6) large datasets. This proceedings paper presents actionable research targets based on the presentations and discussions that occurred at the conference. We summarize the background, main research gaps, overall goals, the panel discussion of the approach, limitations and challenges, and deliverables that were identified.

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Study of the Ultraviolet Effect and Thermal Analysis on Polypropylene Nonwoven Geotextile

Materials ◽

10.3390/ma14051080 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1080

Author(s):

Clever Aparecido Valentin ◽

Marcelo Kobelnik ◽

Yara Barbosa Franco ◽

Fernando Luiz Lavoie ◽

Jefferson Lins da Silva ◽

...

Keyword(s):

Uv Light ◽

Polymeric Materials ◽

Tensile Tests ◽

Thermomechanical Analysis ◽

Material Stiffness ◽

Before And After ◽

Electron Microscopy Analysis ◽

Physical Tests ◽

Nonwoven Geotextile

The use of polymeric materials such as geosynthetics in infrastructure works has been increasing over the last decades, as they bring down costs and provide long-term benefits. However, the aging of polymers raises the question of its long-term durability and for this reason researchers have been studying a sort of techniques to search for the required renewal time. This paper examined a commercial polypropylene (PP) nonwoven geotextile before and after 500 h and 1000 h exposure to ultraviolet (UV) light by performing laboratory accelerated ultraviolet-aging tests. The state of the polymeric material after UV exposure was studied through a wide set of tests, including mechanical and physical tests and thermoanalytical tests and scanning electron microscopy analysis. The calorimetric evaluations (DSC) showed distinct behaviors in sample melting points, attributed to the UV radiation effect on the aged samples. Furthermore, after exposure, the samples presented low thermal stability in the thermomechanical analysis (TMA), with a continuing decrease in their thicknesses. The tensile tests showed an increase in material stiffness after exposition. This study demonstrates that UV aging has effects on the properties of the polypropylene polymer.

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Resistance and Adaptation of Bacteria to Non-Antibiotic Antibacterial Agents: Physical Stressors, Nanoparticles, and Bacteriophages

Antibiotics ◽

10.3390/antibiotics10040435 ◽

2021 ◽

Vol 10 (4) ◽

pp. 435

Author(s):

Sada Raza ◽

Kinga Matuła ◽

Sylwia Karoń ◽

Jan Paczesny

Keyword(s):

Antimicrobial Resistance ◽

Antibacterial Agents ◽

Uv Light ◽

Resistance Mechanisms ◽

Resistant Bacteria ◽

Physical Factors ◽

Defense Systems ◽

Drug Resistant Bacteria

Antimicrobial resistance is a significant threat to human health worldwide, forcing scientists to explore non-traditional antibacterial agents to support rapid interventions and combat the emergence and spread of drug resistant bacteria. Many new antibiotic-free approaches are being developed while the old ones are being revised, resulting in creating unique solutions that arise at the interface of physics, nanotechnology, and microbiology. Specifically, physical factors (e.g., pressure, temperature, UV light) are increasingly used for industrial sterilization. Nanoparticles (unmodified or in combination with toxic compounds) are also applied to circumvent in vivo drug resistance mechanisms in bacteria. Recently, bacteriophage-based treatments are also gaining momentum due to their high bactericidal activity and specificity. Although the number of novel approaches for tackling the antimicrobial resistance crisis is snowballing, it is still unclear if any proposed solutions would provide a long-term remedy. This review aims to provide a detailed overview of how bacteria acquire resistance against these non-antibiotic factors. We also discuss innate bacterial defense systems and how bacteriophages have evolved to tackle them.

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Influence of Alkalinity and Ambient Temperature on Long-Term Properties of GFRP Reinforcement

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.760.213 ◽

2018 ◽

Vol 760 ◽

pp. 213-218

Author(s):

František Girgle ◽

Lenka Bodnárová ◽

Ondřej Januš ◽

Vojtěch Kostiha

Keyword(s):

Tensile Strength ◽

Ambient Temperature ◽

Mechanical Characteristics ◽

Current Problem ◽

Concrete Structures ◽

Experimental Program ◽

Glass Fibres ◽

Metallic Reinforcement ◽

Gfrp Reinforcement

The article deals with the current problem of determining long-term reliability of non-metallic reinforcement in concrete structures. The alkaline environment of concrete with a pH higher than 12.0 affects the glass fibres degradative, whereas this degradation presents by reduction of their mechanical characteristics, resulting in a decrease in the tensile strength of the whole composite. The article summarizes the results of the ongoing experimental program so far, which aims to quantify this influence.

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Effects of Accelerated Aging Period of Time at 180°C on Tensile Property of Plain Woven Fabric/Epoxy Resin Laminated Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.182-183.76 ◽

2012 ◽

Vol 182-183 ◽

pp. 76-79 ◽

Cited By ~ 1

Author(s):

Lei Lei Song ◽

Quan Rong Liu ◽

Jia Lu Li

Keyword(s):

Tensile Strength ◽

Carbon Fiber ◽

Epoxy Resin ◽

Laminated Composites ◽

Accelerated Aging ◽

Woven Fabric ◽

Accelerated Ageing ◽

Time Intervals ◽

Composite Samples

In this paper, carbon fiber reinforced resin matrix composites were produced by stacking eight pieces of carbon fiber woven plain fabric and subjected to accelerated ageing. Accelerated ageing was carried out in oven at 180°C for three different time intervals (60 hours, 120 hours and 180 hours). The influence of different ageing time intervals at 180°C on tensile properties of laminated composites was examined, compared with the composites without aging. The appearance and damage forms of these laminated composites were investigated. The results revealed that the tensile strength of the laminates declined significantly after long term accelerated aging at 180°C. The average tensile strengths of composite samples aged 60 hours, 120 hours, and 180 hours period of time at 180°C are 80.36%, 79.82%, 76.57% of average tensile strength of composite samples without aging, respectively. The high temperature accelerated aging makes the resin macromolecular structure in the composites changed, and then the adhesive force between fiber bundles and resin declines rapidly which result in the tensile strength of composites aged decrease. This research provides a useful reference for long term durability of laminated/epoxy resin composites.

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MERGE OF THE TECHNİCAL ANALYSİS TYPES GİVES THE BEST RESULTS İN CRYPTOCURRENCY MARKET

IEDSR Association ◽

10.46872/pj.312 ◽

2021 ◽

Vol 6 (14) ◽

pp. 89-97

Author(s):

MUSTAFA ÖZYEŞİL ◽

MOHAMMAD AL-TARIFI

Keyword(s):

Supply And Demand ◽

Investment Strategy ◽

Proof Of Concept ◽

Market Capitalization ◽

Long Run ◽

Peer Network ◽

Tangible Asset ◽

The Relationship ◽

Peer To Peer Network

Cryptocurrencies are a modern kind of financial instrument (Hudson & Urquhart, 2019), the first cryptocurrency is Bitcoin , proposed by who called Satoushi Nakamato (2008), as The open source was created on the proof-of-concept principle that transactions can be securely treated on a decentralized peer to peer network without the need for a central clearinghouse, which appeared 2009 ( Heid, 2013). The success of the bitcoin blazes a trail to what called ‘Altcoin” this expression means all the cryptocurrencies that set in motion after the victory of the bitcoin, these coins sell themselves as the best alternatives for the bitcoin (FRANKENFIELD, 2020) . There are many types for the altcoin. The third type of the cryptocurrency is called Tokens Unlike Bitcoin and Altcoins, tokens are not able to activate independently and are dependent on the grid of another cryptocurrency. That means they do not have their own core DLT or blockchain, but instead, are built on top of an existing cryptocurrency’s blockchain (Types of cryptocurrencies: explaining the major types of cryptos, 2019). The worth of bitcoin doesn’t depend on any tangible asset or economies of the countries while it is based upon the security of an algorithm which traces all transactions (Hudson & Urquhart, 2019). The studies determine the number of the bitcoin price development in the long -run (Ciaian, Rajcaniova, & Kancs, 2018): • Market forces of the Bitcoin supply and demand • The bitcoin’s attractiveness for the investors • The influence of global macro-financial developments If you're forming an investment strategy designed to help you trail long-term financial intentions, understanding the relationship between company size, return potential, and risk is vital. (Market cap—or market capitalization—refers to the total value of all a company's shares of stock, 2017) .Hence , Manifested importance a cryptocurrency’s market capitalization as the total values of all coins currently in circulation. the cryptocurrency’s market cap contains what’s called Bitcoin Dominance that is the ratio between the market cap of bitcoin to other coins of the cryptocurrency markets (jacobcanfield, 2019) . Cryptocurrency trade is attractive type of investment. this market treated the same of the foreign exchange and stock market ( Radityo, Munajat, & Budi, 2017). The investors using the same basic in investment (buy low, sell high) but they need to calculating the risks

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An Optical Fiber Sensor Based on La2O2S:Eu Scintillator for Detecting Ultraviolet Radiation in Real-Time

Sensors ◽

10.3390/s18113754 ◽

2018 ◽

Vol 18 (11) ◽

pp. 3754 ◽

Cited By ~ 3

Author(s):

Yongji Yan ◽

Xu Zhang ◽

Haopeng Li ◽

Yu Ma ◽

Tianci Xie ◽

...

Keyword(s):

Optical Fiber ◽

Response Time ◽

Electromagnetic Interference ◽

Uv Light ◽

Optical Fiber Sensor ◽

Temperature Response ◽

Superior Performance ◽

Fiber Sensor ◽

Uv Detectors

A novel ultraviolet (UV) optical fiber sensor (UVOFS) based on the scintillating material La2O2S:Eu has been designed, tested, and its performance compared with other scintillating materials and other conventional UV detectors. The UVOFS is based on PMMA (polymethyl methacrylate) optical fiber which includes a scintillating material. Scintillating materials provide a unique opportunity to measure UV light intensity even in the presence of strong electromagnetic interference. Five scintillating materials were compared in order to select the most appropriate one for the UVOFS. The characteristics of the sensor are reported, including a highly linear response to radiation intensity, reproducibility, temperature response, and response time (to pulsed light) based on emission from a UV source (UV fluorescence tube) centered on a wavelength of 308 nm. A direct comparison with the commercially available semiconductor-based UV sensor proves the UVOFS of this investigation shows superior performance in terms of accuracy, long-term reliability, response time and linearity.

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