River Branch Inspired Janus Textile with Moisture Wicking and UV Resistant Properties

Abstract Discontinuous hydrophobic/hydrophilic Janus fabric resembling river branches is prepared by nano-ZnO pretreatment and screen printing for directional water transport and thermal conductivity properties. A river branch-like structure is constructed dexterously, and the effect is quantitatively adjusted by accurately regulating the gap width of hexagon water-transfer-channel. Fabrics based on these rivers branch-like hexagon structure possess enhanced moisture wicking performance, a desired water transport index of 147.26%, which are over seven times higher than conventional cotton fabrics. Meanwhile, nano-ZnO treatment improves the thermal conductivity of cotton fabric, which accelerates the evaporation of sweat on the surface of cotton fabric. Moreover, nano-ZnO cotton fabric shows an outstanding UV resistant property with 145 UPF value. The novel discontinuous hydrophobic/hydrophilic Janus fabric could provide a new strategy for the development of moisture management textiles.

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Fabrication of temperature-regulating functional fabric based on n-octadecane/SWCNTs composite phase change material

Pigment & Resin Technology ◽

10.1108/prt-06-2021-0058 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Wei Zhang ◽

Jiali Weng ◽

Shang Hao ◽

Yuan Xie ◽

Yonggui Li

Keyword(s):

Thermal Conductivity ◽

Phase Change ◽

Latent Heat ◽

Cotton Fabric ◽

Screen Printing ◽

Scanning Calorimetry ◽

Shape Stability ◽

Content Type ◽

Photothermal Conversion ◽

Fabric Surface

Purpose Fabrics with photothermal conversion functions were developed based on the introduction of shape stable composite phase change materials (CPCMs). Design/methodology/approach Acidified single-walled carbon nanotubes (SWCNTs) were selected as support material to prepare CPCMs with n-octadecane to improve the thermal conductivity and shape stability. The CPCMs were finished onto the surface of cotton fabric through the coating and screen-printing method. The chemical properties of CPCMs were characterized by Fourier transform infrared spectrometer, XRD and differential scanning calorimetry (DSC). The shape stability and thermal conductivity were also evaluated. In addition, the photothermal conversion and temperature-regulating performance of the finished fabrics were analyzed. Findings When the addition amount of acidified SWCNTs are 14% to the mass of n-octadecane, the best shape stability of CPCMs is obtained. DSC analysis shows that the latent heat energy storage of CPCMs is as high as 183.1 J/g. The thermal conductivity is increased by 84.4% compared with that of n-octadecane. The temperature-regulating fabrics coated with CPCMs have good photothermal conversion properties. Research limitations/implications CPCMs with high latent heat properties are applied to the fabric surface through screen printing technology, which not only gives the fabric the photothermal conversion performance but also reflects the design of personalized patterns. Practical implications CPCMs and polydimethylsiloxane (PDMS) are mixed to make printing paste and printed cotton fabric with temperature-regulating functional is developed. Originality/value SWCNTs and n-octadecane are composited to prepare CPCMs with excellent thermal properties, which can be mixed with PDMS to make printing paste without adding other pastes. The fabric is screen-printed to obtain a personalized pattern and can be given a thermoregulatory function.

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Comfort properties of nano-filament polyester fabrics: thermo-physiological evaluation

Industria Textila ◽

10.35530/it.069.04.1529 ◽

2018 ◽

Vol 69 (04) ◽

pp. 315-321 ◽

Cited By ~ 6

Author(s):

AZEEM MUSADDAQ ◽

HES LUBOS ◽

WIENER JAKUB ◽

NOMAN MUHAMMAD TAYYAB ◽

ALI AZAM ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Resistance ◽

Cotton Fabric ◽

Polyester Fabric ◽

Moisture Management ◽

Different Types ◽

Physiological Evaluation ◽

Thermal Comfort Properties ◽

The Aesthetic ◽

Thermal Absorptivity

Comfort along with the aesthetic properties of textile clothing in activewear and sportswear are utmost worthwhile for costumer demand as latest trends. Different types of fibers and yarns are being used to improve the moisture management and comfort of the fabric for next to skin. Nowadays, multifilaments or nano-filaments of polyester with diameters in the range of a few nanometers and lengths up to kilometers are used in different range of important technological applications such as functional fabrics, biomedicine, composite, etc. Multifilament polyester yarns are made by aggregating many continuous filaments together characterized by their high tenacity and large surface area per unit mass. The nano-filament yarn has also significant effects on thermal comfort properties as a nano-filament fabric has less thermal conductivity than cotton fabric, but equal to multichannel polyester fabric while nano-filament fabrics gave the cool feelings with higher thermal absorptivity. Moreover,coolmax fabric showed the higher value of thermal resistance as compared to nano-filament fabrics. Nano-filament fabrics exhibited higher value of watervaporpermeability than cotton fabric.

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Persistent SARS-CoV-2-positive over 4 months in a COVID-19 patient with CHB

Open Medicine ◽

10.1515/med-2021-0283 ◽

2021 ◽

Vol 16 (1) ◽

pp. 749-753

Author(s):

Wenyuan Li ◽

Beibei Huang ◽

Qiang Shen ◽

Shouwei Jiang ◽

Kun Jin ◽

...

Keyword(s):

The Novel ◽

Chain Reaction ◽

Health Crisis ◽

Public Health Crisis ◽

Oxygen Inhalation ◽

New Strategy ◽

Polymerase Chain ◽

Novel Coronavirus ◽

Specific Symptoms

Abstract In recent months, the novel coronavirus disease 2019 (COVID-19) pandemic has become a major public health crisis with takeover more than 1 million lives worldwide. The long-lasting existence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has not yet been reported. Herein, we report a case of SARS-CoV-2 infection with intermittent viral polymerase chain reaction (PCR)-positive for >4 months after clinical rehabilitation. A 35-year-old male was diagnosed with COVID-19 pneumonia with fever but without other specific symptoms. The treatment with lopinavir-ritonavir, oxygen inhalation, and other symptomatic supportive treatment facilitated recovery, and the patient was discharged. However, his viral PCR test was continually positive in oropharyngeal swabs for >4 months after that. At the end of June 2020, he was still under quarantine and observation. The contribution of current antivirus therapy might be limited. The prognosis of COVID-19 patients might be irrelevant to the virus status. Thus, further investigation to evaluate the contagiousness of convalescent patients and the mechanism underlying the persistent existence of SARS-CoV-2 after recovery is essential. A new strategy of disease control, especially extending the follow-up period for recovered COVID-19 patients, is necessary to adapt to the current situation of pandemic.

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Delayed improvement local search

Journal of Heuristics ◽

10.1007/s10732-021-09479-9 ◽

2021 ◽

Author(s):

Heber F. Amaral ◽

Sebastián Urrutia ◽

Lars M. Hvattum

Keyword(s):

Local Search ◽

Heuristic Algorithms ◽

Travelling Salesman Problem ◽

Computation Time ◽

The Novel ◽

Local Optima ◽

New Strategy ◽

Max Cut Problem ◽

Novel Method ◽

Electrospun nanofiber/cotton composite yarn with enhanced moisture management ability

Textile Research Journal ◽

10.1177/0040517520984978 ◽

2021 ◽

pp. 004051752098497

Author(s):

Ning Mao ◽

Xiaohong Qin ◽

Liming Wang ◽

Jianyong Yu

Keyword(s):

Water Transport ◽

Moisture Absorption ◽

Water Evaporation ◽

Electrospun Fibers ◽

Electrospun Nanofiber ◽

Knitted Fabrics ◽

Moisture Management ◽

Composite Yarn ◽

Management Ability ◽

Cotton Yarns

Wet comfort is a critical performance for fabrics, especially when human bodies release sweat in daily life. Despite excellent moisture absorption performance, cotton yarns are still limited in the moisture release/transfer ability. Here, based on a novel electrospinning technology, polyacrylonitrile and polystyrene (PS) electrospun nanofiber/cotton composite yarns were produced, respectively. Under fluorescence microscopic observation, electrospun fibers within the composite yarns showed a uniform distribution. As a result, these composite yarn-based knitted fabrics obtained a good water transport ability and a fast water evaporation rate. According to the moisture management test, PS electrospun nanofiber composite yarn-based fabrics exhibited a relatively high one-way transport index R (400%), claiming an enhanced moisture management performance. Finally, specific surface area tests and finite element analyses were used to analyze the water transport mechanism inside the yarns. The results proved that a small number of electrospun fibers played a predominant role in enhancing the moisture management ability of the composite yarns.

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Estimations on Properties of Redox Reactions to Electrical Energy and Storage Device of Thermoelectric Pipe (TEP) Using Polymeric Nanofluids

Polymers ◽

10.3390/polym13111812 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1812

Author(s):

Qin Gang ◽

Rong-Tsu Wang ◽

Jung-Chang Wang

Keyword(s):

Thermal Conductivity ◽

Power Density ◽

Heat Dissipation ◽

Electrical Energy ◽

Steel Tube ◽

Storage Device ◽

Stainless Steel Tube ◽

The Novel ◽

Empirical Formulas ◽

Dissipative Heat

A thermoelectric pipe (TEP) is constructed by tubular graphite electrodes, Teflon material, and stainless-steel tube containing polymeric nanofluids as electrolytes in this study. Heat dissipation and power generation (generating capacity) are both fulfilled with temperature difference via the thermal-electrochemistry and redox reaction effects of polymeric nanofluids. The notion of TEP is to recover the dissipative heat from the heat capacity generated by the relevant machine systems. The thermal conductivity and power density empirical formulas of the novel TEP were derived through the intelligent dimensional analysis with thermoelectric experiments and evaluated at temperatures between 25 and 100 °C and vacuum pressures between 400 and 760 torr. The results revealed that the polymeric nanofluids composed of titanium dioxide (TiO2) nanoparticles with 0.2 wt.% sodium hydroxide (NaOH) of the novel TEP have the best thermoelectric performance among these electrolytes, including TiO2 nanofluid, TiO2 nanofluid with 0.2 wt.% NaOH, deionized water, and seawater. Furthermore, the thermal conductivity and power density of the novel TEP are 203.1 W/(m·K) and 21.16 W/m3, respectively.

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Thermal Conductivity Performance Modeling and Characterization of a Novel Anisotropic Conductive Adhesive Used in Lead-Free Electronics Packaging

Volume 9: Micro- and Nano-Systems Engineering and Packaging, Parts A and B ◽

10.1115/imece2012-89672 ◽

2012 ◽

Author(s):

Matthew J. Combs ◽

S. Manian Ramkumar ◽

Satish Kandlikar

Keyword(s):

Thermal Conductivity ◽

Base Material ◽

Bond Line ◽

Thermal Interface Material ◽

The Novel ◽

Conductive Adhesives ◽

Curing Conditions ◽

Bond Line Thickness ◽

Significant Research ◽

American Society

The continued desire to utilize an alternative to lead-based solder materials for electrical interconnections has led to significant research interest in Anisotropic Conductive Adhesives (ACAs). The use of ACAs in electrical connections creates bonds using a combination of metal particles and epoxies to replace solder. The novel ACA discussed in this paper allows for bonds to be created through aligning columns of conductive particles along the Z-axis. These columns are formed by the application of a magnetic field, during the curing process. The benefit of this novel ACA is that it does not require precise printing of the adhesive on pads and also enables the mass curing without creating shorts in the circuitry. This paper will present the findings of the thermal conductivity performance tests using the novel ACA and its applicability as a thermal interface material and for assembling bottom termination components, power devices, etc. The columns that act as electrical conduction paths also contribute towards the thermal conductivity. The thermal conductivity of the novel ACA was measured utilizing a system that is similar to that in ASTM (American Society of Testing Materials) D5470 standard. The goal was to examine the influence of Bond Line Thickness (BLT), particle loading densities, particle diameters and adhesive matrix curing conditions on the electrical and thermal performance of the novel ACA. This paper will also present a numerical model to describe the thermal behavior of the novel ACA. The novel ACA’s applicability for PCB-level assembly has also been successfully demonstrated by RIT, including base material characterization, effect of process parameters, failures, and long-term reliability. Reliability testing included the investigation of the assembly performance in temperature and humidity aging, thermal aging, air-to-air thermal cycling, and drop testing.

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Modification of thermal conductivity of cotton fabric using Graphene

2015 Moratuwa Engineering Research Conference (MERCon) ◽

10.1109/mercon.2015.7112320 ◽

2015 ◽

Cited By ~ 1

Author(s):

Ujithe Gunasekera ◽

Nishadi Perera ◽

Shiran Perera ◽

Yasith Hareendra ◽

Lahiru Somaweera ◽

...

Keyword(s):

Thermal Conductivity ◽

Cotton Fabric

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Thermo-physiological Comfort Properties of Polyester and Polyester/Acrylic blended Synthetic Fabrics treated with Herbal Finishes

Journal of Engineered Fibers and Fabrics ◽

10.1177/155892501400900313 ◽

2014 ◽

Vol 9 (3) ◽

pp. 155892501400900

Author(s):

Gunasekaran Govindachetty ◽

Periyasamy Sidhan ◽

Koushik C. Venkatraman

Keyword(s):

Thermal Conductivity ◽

Water Vapor Permeability ◽

The Body ◽

Bermuda Grass ◽

Vapor Permeability ◽

Moisture Management ◽

Hydrophobic Nature ◽

Medicinal Properties ◽

Moisture Vapor ◽

Natural Fabrics

Thermo-physiological comfort in clothing mainly lies in moisture management, which often refers to the transport of both moisture vapor and liquid away from the body. Moisture management of fabrics is chiefly influenced by the thermal properties of those fabrics. In spite of the convincing properties that synthetic fabrics have, they are not much preferred because of their hydrophobic nature which provides less comfort to the wearer compared to the natural fabrics like cotton, wool, and silk. Previous studies report that the herbal finishes, which are eco-friendly in nature, improve the anti-microbial and other medicinal properties but very little or no work has been carried out on the comfort aspect of these fabrics. This work reports a study of the influence of two ecofriendly herbal finishes, Neem and Bermuda grass, on the thermo-physiological comfort properties of synthetic fabrics used in clothing. The herbal finishes were applied on to 100% Polyester and 50/50 Polyester/Acrylic blended fabrics. Prior to the application of finishes, the fabrics were given a pretreatment to achieve a better penetration and durability of the finishes. The finished fabrics were tested for the thermo-physiological comfort properties of Wicking, Water vapor permeability, and Thermal conductivity and the results were analyzed. It was revealed that both the Neem and Bermuda grass natural finishes considerably improved the moisture related properties and moderately reduced the thermal conductivity characteristics of the above synthetic fabrics. Durability to washing was also tested and discussed.

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