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Investigation into the Strength Properties of Plain Cotton Fabrics after Water Immersion for Upcycling Textiles

Yang Chen, Lin Yanping, Zhu Chunyan

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 3

46--55

EN

This study utilized SEM to examine the fiber structure of cotton stock fabrics and tested their durability based on ISO standards. Two types of cotton stock fabrics were evaluated: natural-colored (162 cm width, 120.8 g/m2 weight, 281/10 in × 252/10 in density) and black-colored (157 cm width, 136.1 g/m2 weight, 482/10 in × 210/10 in density). Prolonged water immersion caused surface yarns to loosen, fibers to expand, and the cross-sectional area to increase. Residual pulp and impurities on the fabric adhered to fibers. After 27 days, fiber looseness peaked, leading to complete breakdown after 30 days. Natural-colored fabric experienced significant weft strength loss within 12 days, while black fabric showed slightly higher weft strength loss after 36 days. Color changes were prominent in natural-colored fabric during the initial 21 days, while black fabric displayed noticeable changes after 12 days of immersion.

2

Influence of environmental exposures on electrical parameters of low voltage surge arresters

Pająk Piotr, Szafraniak Bartłomiej, Dąda Anna

Przegląd Elektrotechniczny

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2020

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R. 96, nr 1

56--59

EN

Low voltage surge arresters work in a very different environmental conditions. During the exploitation, under the influence of environmental exposures, the structure of metal oxide surge arresters (MOSA) is gradually degraded. These processes can change their protective properties and lead to a reduction in the effectiveness of surge protection. The aim of the paper is to analyze the influence of environmental exposures on the electrical parameters of low voltage surge arresters.

PL

Warunki środowiskowe w jakich pracują niskonapięciowe ograniczniki przepięć są bardzo zróżnicowane. Podczas eksploatacji, pod wpływem narażeń środowiskowych, struktura ograniczników przepięć ulega stopniowej degradacji. Procesy te mogą powodować zmiany parametrów elektrycznych ograniczników i prowadzić do zmniejszenia skuteczności ochrony przeciwprzepięciowej. Celem referatu jest analiza wpływu narażeń środowiskowych na parametry elektryczne niskonapięciowych ograniczników przepięć.

3

Correlation between compressive strengths and water absorption of fly ash cement mortar immersed in water

Huang Qian, Zhao Liang

Archives of Civil Engineering

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2019

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Vol. 65, nr 3

141--152

EN

The compressive strength and water absorption of cement mortars with different water-binder ratio (0.35, 0.45 and 0.55) and fly ash content (0, 10%, 20% and 30%) under water immersion were investigated, and the correlation between them was further analyzed. The internal microstructure and phase composition of mortar was studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The results show that the inside of mortar mixed with fly ash displayed the loose and porous microstructure. Therefore, the incorporation of fly ash reduced the compressive strength of mortar, especially the early strength, and the strength decreased with the increase of fly ash content, and the water absorption of mortar also increased. There was a linear correlation between the compressive strength and water absorption of mortar with the equation: fc = -3.838β + 62.332, where fc and β represented the compressive strength and water absorption, respectively. Therefore, when the water absorption of mortar immersed in water was measured, its corresponding compressive strength could be preliminarily inferred through this equation, which was of great significance for detecting and identifying the stability and safety of hydraulic structures.