scholarly journals Unmasking the Mask: Investigating the Role of Physical Properties in the Efficacy of Fabric Masks to Prevent the Spread of the COVID-19 Virus

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7756
Author(s):  
Adine Gericke ◽  
Mohanapriya Venkataraman ◽  
Jiri Militky ◽  
Hester Steyn ◽  
Jana Vermaas
Keyword(s):  
Structural Properties ◽  
Woven Fabrics ◽  
Source Control ◽  
Knitted Fabrics ◽  
Performance Properties ◽  
Nonwoven Fabrics ◽  
Textile Fabrics ◽  
Overall Performance ◽  
Textile Fabric

To function as source control, a fabric mask must be able to filter micro-droplets (≥5 µm) in expiratory secretions and still allow the wearer to breathe normally. This study investigated the effects of fabric structural properties on the filtration efficiency (FE) and air permeability (AP) of a range of textile fabrics, using a new method to measure the filtration of particles in the described conditions. The FE improved significantly when the number of layers increased. The FE of the woven fabrics was generally higher, but double-layer weft knitted fabrics, especially when combined with a third (filter) layer, provided a comparable FE without compromising on breathability. This also confirmed the potential of nonwoven fabrics as filter layers in masks. None of the physical fabric properties studied affected FE significantly more than the others. The variance in results achieved within the sample groups show that the overall performance properties of each textile fabric are a product of its combined physical or structural properties, and assumptions that fabrics which appear to be similar will exhibit the same performance properties cannot be made. The combination of layers of fabric in the design of a mask further contributes to the product performance.

An Analysis of the Mechanical Forces in Latch Needle Cam Systems

1992 ◽  
Vol 206 (2) ◽  
pp. 129-137 ◽  
Author(s):  
B L MacCarthy ◽  
J M Sharp ◽  
N D Burns
Keyword(s):  
General Model ◽  
Textile Yarn ◽  
Basic Mechanism ◽  
Normal Operation ◽  
Mechanical Forces ◽  
Knitted Fabrics ◽  
Textile Fabrics ◽  
Cam Profile ◽  
Textile Fabric ◽  
Cam Systems

The majority of textile fabrics are either woven or knitted. Knitted fabrics are most frequently produced on weft knitting machines. The range of machinery is very diverse but the same basic mechanism is employed to convert textile yarn into knitted textile fabric. The mechanism is a specialized needle and cam system known as a latch needle cam system. This paper develops a general model for the mechanical forces that arise in normal operation of a latch needle cam system. The limitations of previous models are noted. The model may be used to predict mechanical forces for any specified cam profile and for the most common needle and cam arrangements. The model will be used in a following paper on yarn forces in latch needle cam systems. The performance of the model will be reported in a following paper describing an experimental programme and experimental results

scholarly journals Influence of washing on the adhesion between 3D-printed TPU and woven fabrics

2021 ◽  
Vol 2 (1) ◽  
pp. 34-39
Author(s):  
Jannik Störmer ◽  
Daniel Görmer ◽  
Andrea Ehrmann
Keyword(s):  
3D Printing ◽  
Strong Correlation ◽  
Thermoplastic Polyurethane ◽  
Cotton Fabrics ◽  
Woven Fabrics ◽  
Textile Fabrics ◽  
Fabric Structure ◽  
High Adhesion ◽  
3D Printed ◽  
Textile Fabric

3D printing on textile fabrics can be used to create composites with position-dependent mechanical, water-resistant, magnetic or other properties. An important prerequisite to use such composites technologically or for design purposes is a sufficient adhesion between both materials. While previous studies revealed that soft, elastic printing polymers were advantageous to prepare connections with a high adhesion, not much research has been performed yet on the dependence of the adhesion on textile fabric structure, heat post-treatment, and the influence of washing, which is necessary for most applications of such composites. Here we investigate composites from thermoplastic polyurethane (TPU) 3D-printed on two different woven cotton fabrics. Besides the expected strong correlation of the adhesion with the distance between nozzle and printing bed, we find a higher adhesion on the thinner fabric and an increase in the adhesion after one washing cycle.

Semantic And Structural Properties Of The Banking And Financial Terminology Of The Uzbek Language

2020 ◽  
Vol 2 (08) ◽  
pp. 610-617
Author(s):  
Ekaterina Turakulovna Shirinova
Keyword(s):  
Structural Analysis ◽  
Structural Properties ◽  
Human Factor

This article discusses information on the study of terminology in Uzbek and world linguistics. Thematic grouping of banking and financial terms, which play an important role in Uzbek language vocabulary, is considered. The author gives the criteria for the distribution of terms into thematic groups, their peculiar properties examples to substantiate the hypothesis. The paradigmatic relations between the terms of this sphere are indicated. A structural analysis of the banking and financial terms of the Uzbek language is carried out.  On the basis of the anthropocentric approach, the role of the human factor in the banking and financial terminology of the Uzbek language is studied. Cognitive metaphors that exist in the terminology are considered.

Sequential risk mitigation and the role of natural recovery in contaminated sediment projects

1998 ◽  
Vol 37 (6-7) ◽  
pp. 331-336 ◽  
Author(s):  
Stephen Garbaciak ◽  
Philip Spadaro ◽  
Todd Thornburg ◽  
Richard Fox
Keyword(s):  
Lower Cost ◽  
Risk Mitigation ◽  
Management Strategies ◽  
Source Control ◽  
Contaminated Sediment ◽  
Practical Observation ◽  
Ecosystem Recovery ◽  
Natural Recovery ◽  
Natural Processes

Sequential risk mitigation approaches the remediation of contaminated sediments in three phases designed to: (1) immediately reduce the ecological and human health risks associated with high levels of contamination, using methods such as the confinement or capping of high-risk materials; (2) reduce the risks associated with moderate levels of pollution to a minimum, on a less urgent schedule and at a lower cost; and (3) address areas of limited contamination through a combination of natural recovery and enhanced natural recovery (to aid or speed those natural processes). Natural recovery, the reduction of contaminant concentrations through natural processes, is based on the practical observation that overall ecosystem recovery appears to be largely a function of time. Sediment decomposition and the mixing of new and old sediments by bottom-dwelling organisms can both contribute to reduced contaminant concentrations. Knowledge of these processes--sediment decomposition, sediment mixing by bottom-dwelling organisms, and chemical residence time is critical in the development of appropriate ecosystem recovery and waste management strategies. Evaluations to support natural recovery predictions are designed to collect and evaluate information necessary to determine whether surface sediment chemical concentrations, with adequate source control, will reach the cleanup standards within a ten-year period.

Emotion information processing as a new component of emotional intelligence: Theoretical framework and empirical evidence

2021 ◽  
pp. 089020702110076
Author(s):  
Marina Fiori ◽  
Shagini Udayar ◽  
Ashley Vesely Maillefer
Keyword(s):  
Emotional Intelligence ◽  
Information Processing ◽  
Incremental Validity ◽  
Stressful Situation ◽  
Factorial Structure ◽  
Ability Emotional Intelligence ◽  
Processing Component ◽  
Overall Performance ◽  
The Relationship

The relationship between emotional intelligence (EI) and emotion information processing (EIP) has received surprisingly little attention in the literature. The present research addresses these gaps in the literature by introducing a conceptualization of emotional intelligence as composed of two distinct components: (1) EIK or emotion Knowledge component, captured by current ability emotional intelligence tests, related to top-down, higher order reasoning about emotions, and which depends more strongly on acquired and culture-bound knowledge about emotions; (2) EIP or emotion information Processing component, measured with emotion information processing tasks, requires faster processing and is based on bottom-up attention-related responses to emotion information. In Study 1 ( N = 349) we tested the factorial structure of this new EIP component within the nomological network of intelligence and current ability emotional intelligence. In Study 2 ( N =111) we tested the incremental validity of EIP in predicting both overall performance and the charisma of a presenter while presenting in a stressful situation. Results support the importance of acknowledging the role of emotion information processing in the emotional intelligence literature and point to the utility of introducing a new EI measure that would capture stable individual differences in how individuals process emotion information.

scholarly journals Dynamical evolution of multiple-population globular clusters

2021 ◽  
Vol 502 (3) ◽  
pp. 4290-4304
Author(s):  
Enrico Vesperini ◽  
Jongsuk Hong ◽  
Mirek Giersz ◽  
Arkadiusz Hypki
Keyword(s):  
Structural Properties ◽  
Globular Clusters ◽  
First Generation ◽  
Radial Profile ◽  
Dynamical Evolution ◽  
Evolutionary Phase ◽  
Dynamical Parameters ◽  
Energy Equipartition

ABSTRACT We have carried out a set of Monte Carlo simulations to study a number of fundamental aspects of the dynamical evolution of multiple stellar populations in globular clusters with different initial masses, fractions of second generation (2G) stars, and structural properties. Our simulations explore and elucidate: (1) the role of early and long-term dynamical processes and stellar escape in the evolution of the fraction of 2G stars and the link between the evolution of the fraction of 2G stars and various dynamical parameters; (2) the link between the fraction of 2G stars inside the cluster and in the population of escaping stars during a cluster’s dynamical evolution; (3) the dynamics of the spatial mixing of the first-generation (1G) and 2G stars and the details of the structural properties of the two populations as they evolve toward mixing; (4) the implications of the initial differences between the spatial distribution of 1G and 2G stars for the evolution of the anisotropy in the velocity distribution and the expected radial profile of the 1G and 2G anisotropy for clusters at different stages of their dynamical history; and (5) the variation of the degree of energy equipartition of the 1G and the 2G populations as a function of the distance from the cluster’s centre and the cluster’s evolutionary phase.

scholarly journals Structural and Technological Approach to Reveal the Role of the Lipid Phase in the Formation of Soy Emulsion Gels with Chia Oil

Gels ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 48
Author(s):  
Ana M. Herrero ◽  
Claudia Ruiz-Capillas
Keyword(s):  
Raman Spectroscopy ◽  
Structural Properties ◽  
Structural Changes ◽  
Protein Secondary Structure ◽  
Lipid Phase ◽  
Α Helix ◽  
Β Sheet ◽  
Shed Light ◽  
Chia Oil

Considerable attention has been paid to emulsion gels (EGs) in recent years due to their interesting applications in food. The aim of this work is to shed light on the role played by chia oil in the technological and structural properties of EGs made from soy protein isolates (SPI) and alginate. Two systems were studied: oil-free SPI gels (SPI/G) and the corresponding SPI EGs (SPI/EG) that contain chia oil. The proximate composition, technological properties (syneresis, pH, color and texture) and structural properties using Raman spectroscopy were determined for SPI/G and SPI/EG. No noticeable (p > 0.05) syneresis was observed in either sample. The pH values were similar (p > 0.05) for SPI/G and SPI/EG, but their texture and color differed significantly depending on the presence of chia oil. SPI/EG featured significantly lower redness and more lightness and yellowness and exhibited greater puncture and gel strengths than SPI/G. Raman spectroscopy revealed significant changes in the protein secondary structure, i.e., higher (p < 0.05) α-helix and lower (p < 0.05) β-sheet, turn and unordered structures, after the incorporation of chia oil to form the corresponding SPI/EG. Apparently, there is a correlation between these structural changes and the textural modifications observed.

scholarly journals Enhancing Firm Performance Through Adoption of Innovation: an Empirical Evidence from Indian Biotechnological Firms

2021 ◽  
Author(s):  
Aishwarya Narayan ◽  
Sumukh Hungund
Keyword(s):  
Firm Performance ◽  
Structural Equation ◽  
Innovation Performance ◽  
Snowball Sampling ◽  
Biotechnology Firms ◽  
Adoption Of Innovation ◽  
Overall Performance ◽  
Innovation Approach ◽  
Innovation Practices

AbstractThis paper explores the influence of innovation approaches on innovation performance and firm performance among Indian biotechnology firms. Further, it aims to discuss the interceding role of innovation performance between innovation practices and firm performance. A criteria-based snowball sampling method was adopted for data collection. The collection of data was carried out using a web survey from 200 biotechnology firms located across India. The data is analysed using a covariance-based structural equation modelling (SEM) technique. The results indicate that the adoption of innovation practices positively influences the firms’ innovation and overall performance. Furthermore, the results confirm the mediating role of innovation performance between innovation approach adoption and firm performance. Firms, particularly from the biotechnology industry, can use these results to assess their performance and formulate or modify their strategy to improve their innovation and overall performance.

Kinematical evolution of Globular Clusters

2019 ◽  
Vol 14 (S351) ◽  
pp. 524-527
Author(s):  
Maria A. Tiongco ◽  
Enrico Vesperini ◽  
Anna Lisa Varri
Keyword(s):  
Angular Momentum ◽  
Structural Properties ◽  
Globular Clusters ◽  
Velocity Dispersion ◽  
Three Dimensional ◽  
Stellar Populations ◽  
Velocity Space ◽  
Fundamental Understanding

AbstractWe present several results of the study of the evolution of globular clusters’ internal kinematics, as driven by two-body relaxation and the interplay between internal angular momentum and the external Galactic tidal field. Via a large suite of N-body simulations, we explored the three-dimensional velocity space of tidally perturbed clusters, by characterizing their degree of velocity dispersion anisotropy and their rotational properties. These studies have shown that a cluster’s kinematical properties contain distinct imprints of the cluster’s initial structural properties, dynamical history, and tidal environment. Building on this fundamental understanding, we then studied the dynamics of multiple stellar populations in globular clusters, with attention to the largely unexplored role of angular momentum.

scholarly journals Analytical investigation of high-velocity impact on hybrid unidirectional/woven composite panels

2016 ◽  
Vol 30 (4) ◽  
pp. 545-563 ◽  
Author(s):  
H Shanazari ◽  
GH Liaghat ◽  
H Hadavinia ◽  
A Aboutorabi
Keyword(s):  
Cross Sections ◽  
Shear Failure ◽  
Failure Criteria ◽  
Analytical Investigation ◽  
Woven Fabrics ◽  
Body Armor ◽  
Ballistic Performance ◽  
Nonwoven Fabrics ◽  
Ballistic Protection ◽  
Maximum Tensile Strain

In addition to fiber properties, the fabric structure plays an important role in determining ballistic performance of composite body armor textile. Textile structures used in ballistic protection are woven fabrics, unidirectional (UD) fabric structures, and nonwoven fabrics. In this article, an analytical model based on wave propagation and energy balance between the projectile and the target is developed to analyze hybrid fabric panels for ballistic protection. The hybrid panel consists of two types of structure: woven fabrics as the front layers and UD material as the rear layers. The model considers different cross sections of surface of the target in the woven and UD fabric of the hybrid panel. Also the model takes into account possible shear failure by using shear strength together with maximum tensile strain as the failure criteria. Reflections of deformation waves at interface between the layers and also the crimp of the yarn are modeled in the woven part of the hybrid panel. The results show greater efficiency of woven fibers in front layers (more shear resistance) and UD yarns in the rear layers (more tensile resistance), leading to better ballistic performance. Also modeling the yarn crimp results in more trauma at the backface of the panel producing data closer to the experimental results. It was found that there is an optimum ratio of woven to UD materials in the hybrid ballistic panel.

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