Multifunctional Dyeing of Wool Fabrics Using Selenium Nanoparticles

This work aims to utilize selenium nanoparticles (Se-NPs) as a novel dyestuff, which endows wool fibers with an orange color because of their localized surface plasmon resonance. The color characteristics of dyed fibers were evaluated and analyzed. The color depth of the dyed fabrics under study was increased with the increase in Se content and dyeing temperature. The colored wool fabrics were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX) and an X-ray diffraction (XRD) analysis. The results indicated that spherical Se-NPs with a spherical shape were consistently deposited onto the surface of wool fibers with good distribution. In addition, the influence of high temperature on the color characteristics and imparted functionalities of the dyed fabrics were also investigated. The obtained results showed that the proposed dyeing process is highly durable to washing after 10 cycles of washes, and the acquired functionalities, mainly antimicrobial activity and UV-blocking properties, were only marginally affected, maintaining an excellent fastness property.

Unfired Clay-Cork Granules Bricks Reinforced with Natural Stabilizers: Thermomechanical Characteristics Assessment

Cork is an ecological, natural, and renewable additive, an excellent thermal and acoustic insulator. All these attributes encourage its use in the building sector. Adding this additive to the Earth leads to a more lightweight composite with better thermal performance than the Earth alone. Unfortunately, the mechanical performance of this composite is degraded significantly, limiting its use in construction applications. The authors propose in this study to stabilize the clay-cork composite using natural stabilizers. A chemical stabilization was tested using local quick-lime, in addition to a physical stabilization using natural sheep-wool fibers. The primary purpose is to propose eco-friendly construction material with enhanced thermal and mechanical properties and the lowest environmental impact based on local and ecological raw materials to encourage more sustainable and low-energy constructions. First, physicochemical and mineralogical characterization of used clay was investigated. Then, an experimental investigation was conducted to identify the lime content that allows the optimal stabilization for the used clay. In this context, many different specimens of Bensmim soil stabilized with lime at six many contents 0, 10, 20, 30, 40, 50, and 70% were prepared and tested. The obtained results showed that the optimal lime content for the better stabilization of the used soil is about 30%. Next, an experimental study of thermomechanical properties was conducted on unfired clay bricks mixed with expended cork granules and stabilized by the addition of variable proportions of quick-lime 0, 10 and 30% and sheep-wool fibers 0, 1, and 2%. The mechanical performance of the specimens was investigated in terms of compressive and flexural strengths. At the same time, thermal quality was qualified through evaluating thermal conductivity using the steady-state Asymmetrical Hot Plate test method. The very encouraging experimental findings showed that using lime and sheep-wool fibers at the studied addition content resulted in lightweight composites with lower thermal conductivity and higher compressive and flexural strength than reference samples. The highest thermomechanical performances are obtained with clay-cork blocks reinforced with 30% lime content and 2% sheep-wool fibers. This block recorded values of 583 kg/m3, 0.155 W/m/K, 1.55 MPa, and 3.91 MPa, for bulk density, thermal conductivity, flexural and compressive strength respectively, compared to 765 kg/m3, 0.238 W/m/K, 0.96 MPa and 2.29 MPa for control samples. New material presents lightweight material for both improved thermal and mechanical qualities encouraging its use in building applications. Doi: 10.28991/cej-2021-03091778 Full Text: PDF

Parameters of breeding traits of sheep of the new breed Artlukhsky merino

The planned breed for breeding in the Republic of Dagestan is Dagestan mountain breed. However, from sheep of this breed fine merino wool is not obtained, and the breeding of special merino breed for mountain and transhumant breeding system is an urgent problem. The purpose of the research was to characterize the main breeding traits in different sex and age groups of sheep of the new breed Artlukhsky merino, such as live weight, wool shearing and its qualitative parameters. Artlukhsky merino breed was bred by using Dagestan mountain breed on the ewes at the beginning stage of the rams of Stavropol breed, and at the final stage – Manych merino breed. The research of the parameters of the breeding traits has been made on elite and class I animals in the breeding farm of the APC “Krasny Oktyabr” in the Kazbekovsky area in the Republic of Dagestan. The live weight of sheep of different sex and age groups of the tested breed was 45–97 kg. The average fineness of wool fibers in adult rams was 23,3 microns (60 quality), in ewes – 22,9 microns (64 quality), in rams aged 12 months – 22,1 microns and young ewes – 20,9 microns (64 quality). The difference in the fineness of the wool on the side and thigh did not exceed one quality. The length of the wool fibers on the side on average in adult rams was at least 9,9 cm, in ewes – 9,4 cm, in young ewes – 10,2 cm and young rams – 10,4 cm. The yield of washed wool in the herd was at the level of 64 %, the fertility of ewes was 125 to 135 %. Thus, the indicators of the main selected traits in sheep of the new breed Artlukhsky merino are at the level of the best domestic breeds, such as Volgograd and Vyatka.

Understanding the difference in softness of Australian Soft Rolling Skin wool and conventional Merino wool

Softness is one of the key elements of textile comfort and is one of the main considerations when consumers make purchasing decisions. In the wool industry, softness can reflect the quality and value of wool fibers. There is verifiable difference in subjective softness between Australian Soft Rolling Skin (SRS) wool and conventional Merino (CM) wool, yet the key factors responsible for this difference are not yet well understood. Fiber attributes, such as crimp (curvature), scale morphology, ortho-to-cortex (OtC) ratio and moisture regain, may have a significant influence on softness performance. This study has examined these key factors for both SRS and CM wool and systematically compared the difference in these factors. There was no significant difference in the crimp frequency between these two wools; however, the curvature of SRS wool was lower than that of CM wool within the same fiber diameter ranges (below 14.5 micron, 16.5–18.5 micron). This difference might be caused by the lower OtC ratio for SRS wool (approximately 0.60) than for CM wool (approximately 0.66). The crystallinity of the two wools was similar and not affected by the change in OtC ratio. SRS wool has higher moisture regain than CM wool by approximately 2.5%, which could reduce the stiffness of wool fibers. The surface morphology for SRS wool was also different from that of CM wool. The lower cuticle scale height for SRS wool resulted in its smoother surface than CM wool. This cuticle height difference was present even when they both had similar cuticle scale frequency.