Graphene versus coronavirus: A study of the graphene properties that can help to combat coronavirus

Coronaviruses ◽  
2021 ◽  
Vol 02 ◽  
Author(s):  
T. Guerra ◽  
I. O. Assis ◽  
A. B. Guerra
Keyword(s):  
Water Molecule ◽  
Graphene Sheet ◽  
Density Functional ◽  
Single Layer ◽  
Face Mask ◽  
Spatial Dimension ◽  
Biological Phenomena ◽  
High Elasticity ◽  
The Face ◽  
Novel Coronavirus

: New and fascinating physical, chemical and biological phenomena arise in ultra-small materials, such as graphene. Graphene is a single layer formed only for carbon atoms, super-strong, 200 times stronger than steel and as much as 6 times lighter. It also has a high elasticity and density. Furthermore, it seems to be impermeable to almost everything, but it allows the passage of water and air. Due to its versatility, modern and urgent applications arise every day, one of the most necessary, currently, is the control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2), the virus responsible for the novel coronavirus disease (COVID-19), which has dimensions around 100 nm and has caused a worldwide public health emergency. Different ways to prevent coronavirus contagion has been proposed and one of them is through the use of masks. Here, we investigated some properties of graphene that can help combat COVID-19. A scale appropriate for comparison shows that the spatial dimension of a virus is much larger than the graphene sheet, making it a great candidate for manufacturing face masks, filters and respirators. We also make use of first-principles calculations, based on the density functional theory (DFT), to investigate the interaction between graphene and a water molecule. We observed that the water molecule undergoes a repulsion force when it is very close to the graphene sheet. The hydrophobicity of graphene can be important to prevent the face mask that doesn’t get wet when you breathe with it.

scholarly journals Making cotton face masks extra-protective by use of impervious cloth as the front layer to restrict flow of aerosols and droplets

2020 ◽  
Author(s):  
Priyanka L Shahane-Kapse ◽  
Moreshwar R Shende ◽  
Sumit Kar ◽  
Pradeep Deshmukh ◽  
Dhiraj Bhandari ◽  
...  
Keyword(s):  
Single Layer ◽  
Middle Layer ◽  
Face Mask ◽  
The Other ◽  
Outer Side ◽  
Carbol Fuchsin ◽  
Triple Layer ◽  
Impervious Layer ◽  
Surgical Masks ◽  
The Face

Introduction: One of the important measures to prevent spread of COVID-19 in community is use of face mask. Though the debate is going on regarding the airborne transmission of SARS-CoV-2 it makes reasonable point for universal use of face masks. A large variety of face masks are available in the market or people can make their own using household items. The efficacy of masks depends upon the type of cloth and number of layers of the cloth. Material and methods: We have created an innovative mask with two layers of cotton and an impervious layer. The impervious layer made from polypropylene coated with polyurethane was applied on the outer side in the middle half of the mask in front of mouth and nose. The efficacy of this test mask was measured against N95FFR (reference standard), triple layer surgical masks and single layer cotton mask. A manikin was used wearing these masks/respirator and aerosols/droplets of diluted red colored carbol fuchsin and fluorescent Auramine O were sprayed from distance of 1m and 2m. We also tested use of face shield. Both macroscopic and microscopic examination of the dissected masks and respirator was performed. Results: The N95FFR was able to block the aerosols/droplets by its front layer. One triple layer surgical mask showed microscopic presence of stain in its innermost layer while the other blocked it with middle layer. The single layer cotton mask was not able to protect as we observed stain on the face itself. The test mask blocked most of the stain on impervious layer and also on the front cotton layer on lateral sides, where impervious layer was absent. When fluorescent stain was used, ultraviolet examination demonstrated that the whole area covered by test mask was clean while the other non covered area was fluorescent. Conclusion: We believe that our innovation can be used in the community as well as in general areas of the hospital like, offices, labs, etc. and can be a better alternative to single use triple layer surgical masks. Further testing may be done by other organizations to rule out bias in our study.

scholarly journals Detection of Hidden Facial Surface Masking in Stored and Real Time Captured Images: A Deep Learning Perspective in Covid Time

2021 ◽  
Vol 38 (6) ◽  
pp. 1875-1885
Author(s):  
Ruchi Jayaswal ◽  
Manish Dixit
Keyword(s):  
Deep Learning ◽  
Real Time ◽  
Preventive Measure ◽  
Face Mask ◽  
Histogram Equalization ◽  
Test Accuracy ◽  
The Face ◽  
Novel Coronavirus ◽  
Face Detector

A novel coronavirus has spread over the world and has become an outbreak. This, according to a WHO report, is an infectious disease that aims to spread. As a consequence, taking precautions is the only method to avoid catching this virus. The most important preventive measure against COVID-19 is to wear a mask. In this paper, a framework is designed for face mask detection using a deep learning approach. This paper aims to predict a person having a mask or unmask and also presents a proposed dataset named RTFMD (Real-Time Face Mask Dataset) to accomplish this objective. We have also taken the RFMD dataset from the internet to analyze the performance of system. Contrast Limited Adaptive Histogram Equalization (CLAHE) technique is applied at the time of pre-processing to enhance the visual quality of images. Subsequently, Inceptionv3 model used to train the face mask images and SSD face detector model has been used for face detection. Therefore, this paper proposed a model CLAHE-SSD_IV3 to classify the mask or without mask images. The system is also tested at VGG16, VGG19, Xception, MobilenetV2 models at different hyperparameters values and analyze them. Furthermore, compared the result of the proposed dataset RTFMD with the RFMD dataset. Additionally, proposed approach is compared with the existing approach on Face Mask dataset and RTFMD dataset. The outcomes have obtained 98% test accuracy on this proposed dataset RTFMD while 97% accuracy on the RFMD dataset in real-time.

scholarly journals Assessment of COVID-19 risk and prevention effectiveness among spectators of mass gathering events

2021 ◽  
Author(s):  
Tetsuo Yasutaka ◽  
Michio Murakami ◽  
Yuichi Iwasaki ◽  
Wataru Naito ◽  
Masaki Onishi ◽  
...  
Keyword(s):  
Face Mask ◽  
Infection Risk ◽  
Exposure Model ◽  
Infection Prevalence ◽  
Mass Gathering ◽  
Local Infection ◽  
Need To Evaluate ◽  
The Face ◽  
Novel Coronavirus ◽  
The Individual

There is a need to evaluate and minimise the risk of novel coronavirus infections at mass gathering events, such as sports. In particular, to consider how to hold mass gathering events, it is important to clarify how the local infection prevalence, the number of spectators, the capacity proportion, and the implementation of preventions affect the infection risk. In this study, we used an environmental exposure model to analyse the relationship between infection risk and infection prevalence, the number of spectators, and the capacity proportion at mass gathering events in football and baseball games. In addition to assessing risk reduction through the implementation of various preventive measures, we assessed how face-mask-wearing proportion affects infection risk. Furthermore, the model was applied to estimate the number of infectors who entered the stadium and the number of newly infected individuals, and to compare them with actual reported cases. The model analysis revealed an 86%-95% reduction in the infection risk due to the implementation of face-mask wearing and hand washing. Among the individual measures, face-mask wearing was particularly effective, and the infection risk increased as the face-mask-wearing proportion decreased. A linear relationship was observed between infection risk at mass gathering events and the infection prevalence. Furthermore, the number of newly infected individuals was also dependent on the number of spectators and the capacity proportion independent of the infection prevalence, confirming the importance of considering spectator capacity in infection risk management. These results highlight that it is beneficial for organisers to ensure prevention compliance and to mitigate or limit the number of spectators according to the prevalence of local infection. Both the estimated and reported numbers of newly infected individuals after the events were small, below 10 per 3-4 million spectators, despite a small gap between these numbers.

Bargaining under social distancing requirements: Effects of face masks on socio-economic decision-making in the COVID-19 pandemic

2020 ◽  
Author(s):  
Ramzi Fatfouta ◽  
Yulia Oganian
Keyword(s):  
Decision Making ◽  
Social Exchange ◽  
Respiratory Diseases ◽  
Face Mask ◽  
The Novel ◽  
Economic Decision Making ◽  
Control And Prevention ◽  
The Face ◽  
Human Social Behavior ◽  
Novel Coronavirus

Face masks play a pivotal role in the control and prevention of respiratory diseases, such as the novel coronavirus (COVID-19). Despite their widespread use, it is not known how face masks affect human social interaction. In this behavioral economics study (N = 475), we examined how mask-wearing modulates individuals’ likelihood of acceptance of unfair monetary offers in an iterated social exchange. Overall, participants accepted more offers, including more unfair offers, from mask-wearing opponents than from opponents without a mask. This effect was enhanced when participants ascribed more altruistic motives to their interaction partner. Importantly, this pattern of results was only present for surgical face masks, but not when a non-medical cloth face covering was used. This is the first study to uncover a new phenomenon, the face-mask effect, in which face masks can alter human social behavior.

The Filtration Efficiency of Single-Layer Textiles for Respiratory protection

2021 ◽  
Vol 3 (2) ◽  
pp. 1-12
Author(s):  
Behnam Pourdeyhimi ◽  
Simon Schick ◽  
Robert Groten
Keyword(s):  
Particle Size ◽  
Single Layer ◽  
Face Mask ◽  
Filtration Efficiency ◽  
Respiratory Protection ◽  
Test Protocol ◽  
Astm Standard ◽  
The Face

Due to the increasing number of corona cases and the face mask industry's associated bottleneck, this work focuses on the various single-layer textiles used as cloth masks. The purpose of this work is to test ten different single-layer textiles for their suitability as face masks. All tests in this work were carried out based on the ASTM F2299 and the new ASTM Standard for barrier masks (3502-21). The new standard offers a more precisely defined test protocol and is consistent with how respirators are tested. The results show that only one of the ten textiles tested meets the ASTM requirements for a barrier mask. We also include data for ASTM F2299 and report the results for unneutralized challenge particles at various face velocities for the same single-layer textiles. These results are different from those of the ASTM 3502 because the particle size and the procedure used are different.  Under ASTM 3502, the resistance values ​​are significantly higher, and the efficiency values ​​are significantly lower than those reported by using the ASTM F2299.

scholarly journals Efficacy of face masks, neck gaiters and face shields for reducing the expulsion of simulated cough-generated aerosols

2020 ◽  
Author(s):  
William G. Lindsley ◽  
Francoise M. Blachere ◽  
Brandon F. Law ◽  
Donald H. Beezhold ◽  
John D. Noti
Keyword(s):  
Double Layer ◽  
Aerosol Particles ◽  
Single Layer ◽  
Face Mask ◽  
Cotton Cloth ◽  
Source Control ◽  
The Face ◽  
Community Transmission ◽  
Small Aerosol ◽  
Control Devices

AbstractFace masks are recommended to reduce community transmission of SARS-CoV-2. One of the primary benefits of face masks and other coverings is as source control devices to reduce the expulsion of respiratory aerosols during coughing, breathing, and speaking. Face shields and neck gaiters have been proposed as an alternative to face masks, but information about face shields and neck gaiters as source control devices is limited. We used a cough aerosol simulator with a pliable skin headform to propel small aerosol particles (0 to 7 µm) into different face coverings. An N95 respirator blocked 99% of the cough aerosol, a medical grade procedure mask blocked 59%, a 3-ply cotton cloth face mask blocked 51%, and a polyester neck gaiter blocked 47% as a single layer and 60% when folded into a double layer. In contrast, the face shield blocked 2% of the cough aerosol. Our results suggest that face masks and neck gaiters are preferable to face shields as source control devices for cough aerosols.

Using the mask – Do’s and Don’ts in the COVID-19 scenario

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 901-906
Author(s):  
Sherly Deborah G ◽  
Archana R ◽  
Harini Narayanam
Keyword(s):  
Preventive Measures ◽  
Treatment Options ◽  
Face Mask ◽  
Nasal Discharge ◽  
The Novel ◽  
Physical Barrier ◽  
Protective Measures ◽  
Surrounding Environment ◽  
The Face ◽  
Novel Coronavirus

A face mask is a loose-fitting, disposable outfit that acts as a physical barrier between the mouth and nose of an individual and the potential pollutants in the surrounding environment. COVID-19 which is also called as 2019-nCov is caused by the novel coronavirus and it is spread by the salivary droplets or nasal discharge released when an infected person coughs or sneezes. In the current COVID -19 scenario, the face mask is designed to ameliorate the prevention of airborne transmission of the novel coronavirus. The use of face mask is competent only when the other personal preventive measures are ideally pursued. The effectiveness of the use of face mask depends strongly on the do’s and don’ts which has to followed while wearing a face mask. The purpose of this study is to analyze and summarize the published literature associated with the types, usage, risks, limitations, disposal and reusability of face mask. The availability of medication and treatment options are sparse and the development of vaccines for COVID-19 is going to take a longer time. Hence the most effective strategy to curb the spread of the disease is by the judicious use of face mask along with other personal protective measures.

scholarly journals Mask associated dermatosis: unmasking the challenges- a cross sectional study

2021 ◽  
Vol 7 (4) ◽  
pp. 547
Author(s):  
Ketki . ◽  
Sonali Gupta ◽  
Vijay Paliwal ◽  
Rachita Mathur ◽  
Deepak K. Mathur
Keyword(s):  
Preventive Measure ◽  
Face Mask ◽  
Cross Sectional Study ◽  
World Health ◽  
Sectional Study ◽  
Cross Sectional ◽  
Short Period ◽  
The Face ◽  
Novel Coronavirus ◽  
Health Organization

<p class="abstract"><strong>Background: </strong>The novel coronavirus, referred to as SARS-COV 2 causing COVID 19, has become a great health challenge to the mankind. After its origin from Wuhan, China, it spread all over the globe within a short period of time. World Health Organization (WHO) officially declared COVID 19 as pandemic on 11th March, 2020. Aerosoles or droplets are the commonest mode of infection through respiratory tract making it mandatory to wear masks as a preventive measure.</p><p class="abstract"><strong>Methods: </strong>It is a cross-sectional study conducted over patients attending the out patients department of Dermatology. They were observed for presence of dermatosis over the face and categorized according to nature of dermatoses.</p><p class="abstract"><strong>Results:</strong> We observed 385 patients, 200 (52%) patients had new dermatoses and 185 (48%) patients noticed flare of existing dermatoses. The predominant new dermatoses were dermatophytosis, indentations, sweat induced dermatitis, urticaria, pressure urticaria developing with indentations, contact dermatitis to metal and other materials in 49 (24.5%%), 42 (21%), 42 (21%) ,38(19%), 19 (9.5%) and 10 (5%) cases respectively. The flared dermatoses were acne, rosacea , plane warts and molluscum contagiosum in 120 (64.8%), 24 (12.9%), 22 (11.9%) and 17 (9.2%) cases respectively. Koebnerisation of vitiligo and lichen planus was also seen in few subjects.</p><p class="abstract"><strong>Conclusions:</strong> The prolonged use of face mask may cause various infective and non infective facial dermatoses. In the current scenario, it is mandatory to wear face mask as a preventive measure hence it is important to wear the mask properly. However, care of the mask as well as breaks from the mask are important factors to avoid the development of mask associated dermatosis.</p>

Ab initio calculation on the Optical Properties of AA- Stacked two dimensional Graphene, Silicene, Germanene, and Stanene

2018 ◽  
Vol 1 (1) ◽  
pp. 46-50
Author(s):  
Rita John ◽  
Benita Merlin
Keyword(s):  
Optical Properties ◽  
Band Structure ◽  
Density Functional ◽  
Electronic Band Structure ◽  
Complex Refractive Index ◽  
Single Layer ◽  
Generalized Gradient ◽  
Electronic Band ◽  
Wide Range ◽  
Optical Region

In this study, we have analyzed the electronic band structure and optical properties of AA-stacked bilayer graphene and its 2D analogues and compared the results with single layers. The calculations have been done using Density Functional Theory with Generalized Gradient Approximation as exchange correlation potential as in CASTEP. The study on electronic band structure shows the splitting of valence and conduction bands. A band gap of 0.342eV in graphene and an infinitesimally small gap in other 2D materials are generated. Similar to a single layer, AA-stacked bilayer materials also exhibit excellent optical properties throughout the optical region from infrared to ultraviolet. Optical properties are studied along both parallel (||) and perpendicular ( ) polarization directions. The complex dielectric function (ε) and the complex refractive index (N) are calculated. The calculated values of ε and N enable us to analyze optical absorption, reflectivity, conductivity, and the electron loss function. Inferences from the study of optical properties are presented. In general the optical properties are found to be enhanced compared to its corresponding single layer. The further study brings out greater inferences towards their direct application in the optical industry through a wide range of the optical spectrum.

DFT study on the hydrolysis of metsulfuron-methyl: A sulfonylurea herbicide

2018 ◽  
Vol 17 (08) ◽  
pp. 1850050 ◽  
Author(s):  
Qiuhan Luo ◽  
Gang Li ◽  
Junping Xiao ◽  
Chunhui Yin ◽  
Yahui He ◽  
...  
Keyword(s):  
Free Energy ◽  
Water Molecule ◽  
Carbonyl Group ◽  
Energy Barrier ◽  
Density Functional ◽  
Free Energy Barrier ◽  
Functional Theory ◽  
Metsulfuron Methyl ◽  
Catalytic Role ◽  
Hydrolysis Of

Sulfonylureas are an important group of herbicides widely used for a range of weeds and grasses control particularly in cereals. However, some of them tend to persist for years in environments. Hydrolysis is the primary pathway for their degradation. To understand the hydrolysis behavior of sulfonylurea herbicides, the hydrolysis mechanism of metsulfuron-methyl, a typical sulfonylurea, was investigated using density functional theory (DFT) at the B3LYP/6-31[Formula: see text]G(d,p) level. The hydrolysis of metsulfuron-methyl resembles nucleophilic substitution by a water molecule attacking the carbonyl group from aryl side (pathway a) or from heterocycle side (pathway b). In the direct hydrolysis, the carbonyl group is directly attacked by one water molecule to form benzene sulfonamide or heterocyclic amine; the free energy barrier is about 52–58[Formula: see text]kcal[Formula: see text]mol[Formula: see text]. In the autocatalytic hydrolysis, with the second water molecule acting as a catalyst, the free energy barrier, which is about 43–45[Formula: see text]kcal[Formula: see text]mol[Formula: see text], is remarkably reduced by about 11[Formula: see text]kcal[Formula: see text]mol[Formula: see text]. It is obvious that water molecules play a significant catalytic role during the hydrolysis of sulfonylureas.

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