Hasil untuk "Textile bleaching, dyeing, printing, etc."

Dong Wei, Zuobiao Li, Zhiqiang Gu et al.

To promote the application of recycled concrete in construction engineering, the flexural behavior of ultra-high toughness cement-based composite (UHTCC) materials and recycled concrete composite beams was investigated in this study. Recycled aggregates were used in the production of both recycled UHTCC (R-UHTCC) and recycled concrete. A total of 10 beams were manufactured and tested under four-point bending load. The primary design parameters included concrete strength grade, R-UHTCC layer height, stirrup spacing in the pure bending section, and tensile reinforcement ratio. The effects of these parameters on the failure mode, crack width, load-midspan deflection response, ductility, load-tensile reinforcement strain response, and flexural capacity of the beams are discussed. The results indicate that limiting the use of R-UHTCC to a specific height range within the tensile zone of the beams can yield superior flexural properties compared to using R-UHTCC across the full section. The R-UHTCC and recycled concrete composite beams demonstrated good crack resistance, load-deflection response, and ductility. Compared to the R-UHTCC layer height and stirrup spacing, the influences of concrete strength and tensile reinforcement ratio on the flexural behavior of the composite beams are more significant. The maximum increase in flexural capacity and ductility index was 18.8% and 67.3%, respectively, as the concrete strength grade increased from C30 to C70. The flexural capacity increased by 64.6% as the longitudinal reinforcement ratio increased from 0.258% to 3.68%. Furthermore, a stiffness calculation method based on the effective moment of inertia was proposed and validated through experimental results. The research findings provide a theoretical and design basis for the application of R-UHTCC and recycled concrete composite beams in engineering.

Armine Ulukhanyan, Luca Placidi, Anil Misra et al.

In this contribution, the classical Cauchy first-gradient elastic theory is used to solve the equilibrium problem of a bidimensional (2D) reinforced elastic structure under small displacements and strains. Such a 2D first-gradient continuum is embedded with a reinforcement, which is modeled as a zero-thickness interface endowed with the elastic properties of an extensional Euler–Bernoulli 1D beam. Modeling the reinforcement as an interface eliminates the need for a full geometric representation of the reinforcing bar with finite thickness in the 2D model, and the associated mesh discretization for numerical analysis. Thus, the effects of the 1D beam-like reinforcements are described through proper and generalized boundary conditions prescribed to contiguous continuum regions, deduced from a standard variational approach. The novelty of this work lies in the formulation of an interface model coupling 1D and 2D continua, based on weak formulation and variational derivation, capable of accurately capturing stress distributions without requiring full geometric resolution of the reinforcement. The proposed framework is therefore illustrated by computing, with finite element simulations, the response of the reinforced structural element under uniform bending. Numerical results reveal the presence of jumps for some stress components in the vicinity of the reinforcement tips and demonstrate convergence under mesh refinement. Although the reinforcement beams possess only axial stiffness, they significantly influence the equilibrium configuration by causing a redistribution of stress and enhancing stress transfer throughout the structure. These findings offer a new perspective on the effective modeling of fiber-reinforced structures, which are of significant interest in engineering applications such as micropiles in foundations, fiber-reinforced concrete, and advanced composite materials. In these systems, stress localization and stability play a critical role.

P. Miladinova, Dimitrina Atanasova Todorova

Magdalena Georgievska, Abreha Bayrau Nigusse, Benny Malengier et al.

Though the transition from disposable to reusable surgical gowns holds substantial promise, successful implementation faces challenges. This study investigated tactile and thermophysiological comfort in surgical reusable gowns, comparing them with their disposable counterparts. Parameters such as surface roughness, compression, heat flux, and material rigidity were tested using a Fabric Touch Tester. Additionally, the water vapour permeability and static charge of the gowns were assessed. Thermophysiological comfort of the gowns was evaluated by measuring the temperature and relative humidity (RH) on test subjects during wear trials where they were engaged in an activity that mimics a surgeon’s performance. Skin temperature was monitored using iButton sensors and a thermal camera, and the impact on heart rate during the task was analysed. Following each test, participants provided subjective feedback through a questionnaire. The results indicated that reusable gowns boasted a smoother texture, translating to reduced friction on the skin and better heat transfer compared to the disposable fabrics, as indicated using FTT. They also exhibited higher water vapour permeability compared to their disposable counterparts. The wear trials revealed minimal differences in comfort between disposable and reusable gowns. While performing the activity, an increase in body temperature led to decreased RH, yet this rise did not adversely affect subject comfort, as validated using heart rate and questionnaire survey data. From a comfort point of view, switching from disposable to reusable gowns would not have drawbacks, meaning hospitals should be able to switch provided logistics and costs can be managed.

Boyan Chang, Yang Zhou, Guoguang Jin et al.

The comber is very important in the spinning for high quality yarns, in which the nipper mechanism (NM) determines the quality of the yarn it combs. This paper is to connect topology and multi-body dynamics to reveal the principle of impact motion of the nipper mechanism. Firstly, the working process of the NM is analyzed and corresponding kinematic models of work sub-phases are derived. Subsequently, the transition from the work phase of the jaw closed to the opened is studied. The research results show that during the transformation process, the mechanism presented another work phase with multiple impacts, which is the main reason why the NM could not stably clamp the cotton clump and thus affect the quality of the yarn combed by the comber. According to the relative coordinate method, the dynamic model of the NM is set up. Combining the classical collision theory and the restitution coefficient equation, the acquisition of the impact impulse generated at the jaw and the subsequent motion of the mechanism are decided. Finally, the NM in the E62 comber is taken as an example to verify the correctness of the established dynamic model, and the influences of different input speeds, restitution coefficients, and stiffness coefficients of spring on the jaw’s impact are studied. This has certain theoretical value for improving the speed and efficiency of the comber.

Zayedul Hasan, Rochak Rathour, Apurba Das et al.

Current cut protective gear is subject to several difficulties, such as the use of heavy fabric, complicated donning processes, lack of comfort and limited movement. When selecting the most comfortable cut protective fabric, it is important to consider the end users' specific needs. The aim of this study was to enhance the comprehension and optimisation of protective apparel for superior occupational safety and protection by exploring the intricate link between material composition, yarn structure and comfort parameters. Various combinations of filament twisted core sheath yarn consisting of stainless-steel/glass with high-performance polyethylene and polyester wraps were used to fabricate thermo-physiological comfortable cut protective workwear fabric. Twelve cut protective fabrics with the same areal density (200 g/m2) were prepared with 6-end satin weave using filament twisted core sheath yarn of five distinct linear densities (98.4 tex, 73.8 tex, 59.1 tex, 49.2 tex and 39.4 tex). These fabric samples were used to evaluate thermophysiological characteristics, including air permeability, dry and evaporative heat resistance, thermal conductivity, moisture permeability, wettability and moisture wicking according to the established standard. The cut protection of each sample was also measured according to EN 13997. The cut protection and thermo-physiological comfort attributes of cut-resistant clothing are greatly influenced by the proportion of core material (stainless-steel/glass) and yarn structural parameters (linear density and twist direction), which was observed by analysing the results. An increased core material percentage (stainless-steel/glass) contributes to increased fabric thickness and reduced bulk density, which influences the thermophysiological comfort attributes of the developed cut protective workwear fabric. Fabric made from a higher proportion of core material (stainless-steel/glass) with a lower bulk density exhibited an acceptable cut protection level and performed better in terms of thermo-physiological comfort attributes.

Neha, Pradeep Joshi, Nishant Kumar

The fast fashion boom is faced with economic, environmental and social justice objections. Sustainable mar­keting initiatives have become a new style statement, and brands are shifting to environment-friendly manufacturing. This study explores how fashion apparel brands adopt sustainable marketing practices to promote sustainable purchase behaviour. A cross-sectional survey using a quantitative research design was followed to collect responses from fashion brand consumers. Variance-based partial least squares-structural equation modelling (PLS-SEM) was used to assess the hypothesized model. Two-step bootstrapping was conducted to explore the mediating role of brand perception in the relationship between sustainable marketing activity and brand loyalty. The study suggests that firms can support sustainable marketing practices by creating a brand image and building trust. This can influence consumers' perceptions of sustainability and promote brand loyalty. The study also emphasizes the significance of brand loyalty in developing sustainable purchase behaviour that endures over time. The study provides insights into sustainable marketing strategies and pol­icies in indigenous markets.

Dongxiu Guo, Ali Rajabipour, Milad Bazli et al.

This study assesses the usability of natural materials available in Australia’s remote communities for making fibre-reinforced mudbricks. The present construction cost for housing in remote areas is too high to maintain the level of housing required for the remote Australian population. As this includes mostly First Nations communities, more culturally appropriate housing materials and construction methods are being considered. This study looks at mudbricks made from laterite soil reinforced by spinifex fibre, both available in abundance in remote communities. Hence, this material is more acceptable to communities as it is more sustainable, and the construction methods are more suited for First Nations engagement. Various mixes were tested for compressive strength and erosion resistance. Results suggest that spinifex can significantly improve compressive strength and reduce erosion effects; however, spinifex showed adverse effects at the early stage of the spray test. The results satisfy the minimum strength and erosion resistance requirements for construction and suggest that spinifex-reinforced mudbricks could potentially be considered as an alternative material in remote housing.

G. Ramaiah, A. Mequanent, R. Legese et al.

Printing is the process of transferring a specific pattern or design onto the surface of textile fabric. In the printing process, screen printing is one of the fundamental printing methods on textiles and is widely used worldwide. However, screen-printed fabrics have specific properties like fastness, water absorbency, and whiteness index that increase the end-use properties of the printed fabrics. There are several factors that affect the technical characteristics of printed fabrics. This research focuses on an experimental approach to ascertain and confirm the pre-treatment process as one of the most important factors in pigment dye screen-printed fabrics. The main raw material used in this research was 100% cotton fabric with a plain weave structure. The experimental method used in this research involved the pre-treatment (singeing, scouring, and bleaching) process with different recipes and four samples. Screen-printed fabric after printing was tested for its technical properties using standard test methods. The results of a one-way ANOVA (Analysis of Variance) were analysed using MINITAB and Microsoft (MS) Excel software. The results indicate superior fabric technical properties like color fastness to rubbing and washing, coupled with improved water absorbency and excellent whiteness index values of samples printed after bleaching with Hydrogen Peroxide (H2O2). In this research, we conclude that printed fabric after bleaching with H2O2 has the best color fastness, and bleaching with NaOCl is the next one. However, printed fabric has a low fastness property after scouring and singeing.

Giovanna Rizzo, Roberto Buccione, Marilena Dichicco et al.

A multi-analytical study on serpentinites in the ophiolite units (Calabria-Basilicata boundary, southern Apennines) was carried out on samples collected from a serpentinite quarry, locally called “Pietrapica”, which sitsin the Pollino UNESCO Global Geopark. Optical microscopy observations revealed the petrographic characteristics, ICP-MS was used to assess the chemical composition while EMPA mineral chemistry, Raman spectroscopy and X-Ray Powder Diffraction and were used altogether to trace the mineral composition of the rocks. Petrography revealed that serpentinites from Pietrapica quarry are essentially composed of serpentine group minerals, amphibole and carbonate minerals with lower abundances of talc and Cr-spinel. Raman spectroscopy and X-ray powder diffraction analysis clearly allowed to establish that carbonate minerals, serpentine and amphibole-like minerals, are the dominant phases, followed by 2:1 phyllosilicate. Electron probe microanalyses were carried out on different minerals in serpentinites samples including serpentine, amphibole, chlorite, clinopyroxene, magnetite, talc, quartz and titanite which are often associated with carbonate veins. Bulk geochemistry is dominated by major oxides SiO₂, MgO and Fe₂O₃ while the most abundant trace elements are Ni and Cr. Chemical analysis showed that some heavy metals in the studied serpentinites such as Ni and Cr, are beyond the maximum admissible limits for Italian normative for public, private and residential green as well as for commercial and industrial use representing a potential environmental concern. Anyway, some of these heavy metals have been recently listed by Europe as critical raw materials and therefore, the Pietrapica abandoned quarry could represent a new resource considering their economic potentiality.

R. Rehman, Asma Raza, F. Yasmeen et al.

The usage of dyes has been tremendously augmented due to industrialization and human’s intrinsic fascination with colors. Owing to their excessive usage in industries like textiles, food, cosmetics, paints, printing etc., it is indisputably a contributing factor in aquatic pollution. Dyes effluents have emerged as a burgeoning challenge. Owing to issues such as toxicity, mutagenicity, and disturbed photosynthesis associated with dye contamination, it is crucial to look for an explication to deal with this challenge. Polypyrrole-based biocomposites have been reported as good adsorbents for textile wastewater treatment. In the last decade, numerous studies have stated the effective removal of dyes via Polypyrrole-based biocomposites. This review concentrates on the implication of different Polypyrrole-based biocomposites for decontamination of dyes and synthesis methods, characteristics, and mechanism of dyes degradation by these biocomposites from wastewater.

Tanya Bhayana, Ambika Saxena, Sarika Gupta et al.

Xiaofei Gao, Qi Lizhe, Ma Chuangjia et al.

A vision-based sewing trajectory extraction method aims at the difficulty of adaptive generation of sewing trajectory in garment automatic processing. Firstly, the ENet model is improved and the I-ENet semantic segmentation algorithm is proposed; Then, based on the semantic segmentation results, a dynamic edge extraction method based on the GaussMod fitting method is proposed. Based on segmented images, curve fitting, median filtering, and edge-preserving filtering are used. Finally, the Canny operator is used to find the sewing edge trajectory curve. At last, the sewing trajectory curve of the robot is generated. Through experimental verification, the MIoU and PA of the semantic segmentation algorithm I-ENet proposed in this paper reach 95.06% and 97.80% respectively. Compared with the MIoU of the original model of ENet, the MIoU is improved by 2.78%, the pixel accuracy is improved by 1.18%, and the frame rate is 30 FPS. It can realize cloth segmentation and extraction in an unstructured environment. The maximum error between the sewing edge trajectory and the actual edge is 1.35 mm, the mean error is 0.61 mm, and the mean value of dynamic variance is 0.57 mm. This method meets the practical application requirements.

G.L. Devnani, Shishir Sinha

This article focuses on the utilization of cellulosic fiber African Teff straw, for the fabrication of epoxy composites. 5 and 10% NaOH solution is used for surface treatment of fiber. Compositional and XPS analysis is preformed for untreated and treated fibers and O/C ratio is evaluated. Impact, morphology, crystallinity, thermal characteristics and activation energy of untreated and alkali-treated Epoxy composites reinforced by this fiber are studied. Isoconversional FWO and Friedman are applied for understanding the degradation behavior along with apparent activation energy of composites. 5% alkali-treated composites have improved thermal stability and has apparent activation energy 249 kJ/mol, which is 16% higher compared to untreated composites. Compositional and XPS (X-ray photoelectron spectroscopy) analysis of fiber and characterization of composites along with XRD (X-ray diffraction) analysis also support these findings. Composites reinforced by optimally treated fiber can be utilized for semi structural applications

Bydełek Arkadiusz, Berdychowski Maciej, Talaśka Krzysztof

This article presents a method for modeling the material characteristics of synthetic fabrics based on static tensile test results with consideration of material orthotropy. Material characteristics were determined for fabrics under load at three different angles in relation to their orthotropy. The fabrics examined were the following: polyester fabrics Bratex and Ortalion, cotton fabric with nylon and elastin fabric (poplin), and Gore-Tex membrane fabric. Considering the material mechanical characteristics, the differences were in grammage, maximum strain, and tensile strength. The study allowed us to determine the nonlinear elastic dependency between strain and stress. Test results were implemented within the Abaqus/Explicit framework for the purpose of performance of verification simulations. The correlation between simulated and experimental results was established. A high degree of similarity allows us to classify the obtained material model as usable in simulation work.

Thisara Sandanuwan, N. Hendeniya, D. Amarasinghe et al.

Abstract In textile dyeing and printing, fabric wettability plays a major role for good surface finish. Woven cotton fabrics contains starch, accumulated from sizing agents used for yarns which needs to be removed before coloration and finishing processes. The conventional method of removing the starch and making the cotton fabric ready for further steps is a wet chemical treatment that uses desizing, scouring, and bleaching agents in the process which has drawbacks of consumption of large amount of water and energy and pollution from effluents. The need for an environmentally friendly, cost-effective, and energy-efficient desizing method is in the interest of the industry. During this study, the effect of atmospheric pressure plasma treatment on the enhancement of wettability and dyeing properties of cotton fabric was studied.

K. Grenda, J. Gamelas, J. Arnold et al.

In wastewater treatment, flocculation is a widely used solid/liquid separation technique, which typically employs a charged polymer, a polyelectrolyte (PEL). Polyelectrolytes features, such as charge type, charge density and molecular weight, are essential parameters affecting the mechanism of flocculation and subsequent floc sedimentation. The effectiveness of the process is also influenced by the characteristics of the system (e.g., type, size, and available surface area of suspended particles, pH of the medium, charge of suspended particles). Thus, a good understanding of the flocculation kinetics, involved mechanisms and flocs structure is essential in identifying the most adequate treatment conditions, having also into consideration possible subsequent treatments. In this study, Eucalyptus bleached pulp and a cellulosic pulp with high lignin content (~4.5 wt%) obtained from Eucalyptus wood waste were used for bio-PELs production. Firstly, a pre-treatment with sodium periodate increased the pulps reactivity. To produce cationic cellulose the oxidation step was followed by the introduction of cationic groups in the cellulose chains, through reaction with Girard's reagent T. Applying different molar ratios (0.975 and 3.9) of Girard's reagent T to aldehyde groups led to cationic PELs with diverse charge density. On the other hand, to obtain anionic cellulose a sulfonation reaction with sodium metabisulfite was applied to the intermediate dialdehyde cellulose-based products, during 24 or 72 h, and anionic-PELs with diverse features were obtained. The developed water soluble, anionic and cationic bio-PELs were characterized and tested as flocculation agents for a textile industry effluent treatment. Initially, jar-tests were used to tune the most effective flocculation procedure (pH, flocculant dosage, etc.). Flocculation using these conditions was then monitored continuously, over time, using laser diffraction spectroscopy (LDS). Due to the small size of the dyes molecules, a dual system with an inorganic complexation agent (bentonite) was essential for effective decolouration of the effluent. Performance in the treatment was monitored first by turbidity removal evaluation (75–88% with cationic-PELs, 75–81% with anionic-PELs) and COD reduction evaluation (79–81% with cationic-PELs, 63–77% with anionic-PELs) in the jar tests. Additionally, the evolution of flocs characteristics (structure and size) during their growth and the flocculation kinetics, were studied using the LDS technique, applying the different PELs produced and for a range of PEL concentration. The results obtained through this monitoring procedure allowed to discuss the possible flocculation mechanisms involved in the process. The results obtained with the bio-PELs were compared with those obtained using synthetic PELs, commonly applied in effluents treatment, polyacrylamides. The developed bio-PELs can be competitive, eco-friendly flocculation agents for effluents treatment from several industries, when compared to traditional synthetic flocculants with a significant environmental footprint. Moreover, LDS proved to be a feasible technique to monitor flocculation processes, even when a real industrial effluent is being tested.

Anton V. Bourdine, Alexey Yu. Barashkin, Vladimir A. Burdin et al.

This work presents fabricated silica microstructured optical fiber with special equiangular spiral six-ray geometry, an outer diameter of 125 µm (that corresponds to conventional commercially available telecommunication optical fibers of ratified ITU-T recommendations), and induced chirality with twisting of 200 revolutions per minute (or e.g., under a drawing speed of 3 m per minute, 66 revolutions per 1 m). We discuss the fabrication of twisted microstructured optical fibers. Some results of tests, performed with pilot samples of designed and manufactured stellar chiral silica microstructured optical fiber, including basic transmission parameters, as well as measurements of near-field laser beam profile and spectral and pulse responses, are represented.

Dimitrijević Dragan

An important element of the policy of development and modernization of each country is the establishment of a program of balanced long-term development, which must be complementary with strategic priorities and national characteristics, as well as the real state and prospects of technical and technological development of science and industry. Therefore, manufacturing entrepreneurship today, would have to combine scientific research activities, education sector and public administration with production, in order to ensure efficient acquisition of new knowledge and skills, along the generation and production-economic valorization of innovations and diffusion and implementation of technical-technological innovations and new technologies, with priority reliance on ICT (information and communication technologies). It is obvious that sustainable competitiveness, in times of general and business globalization, is no longer in quantitative-qualitative aspects of production, but in new elements of production specialization, adequate and timely implementation of technical-technological innovations, in organizational innovations, in the way cluster business and in global efficiency, as well as in close and flexible connection of design, planning, production technologies and production, with the possibility of quick response (JustInTime and QuickResponseSystem) to the changes required by the market. That is why today the issue of redefining the way of work and business of textile/clothing industry companies is more than current, in fact the issue of redefining the strategic programs of economic development of developing countries.

Tatiana V. Plisko, Alexandr V. Bildyukevich, Liang Zhao et al.

This study deals with the investigation of the phase state of the polymer systems from polysulfone (PSF) with the addition of polyethylene glycol (PEG-400, M_n = 400 g·mol⁻¹) and polyvinylpyrrolidone (PVP K-30, M_n = 40,000 g·mol⁻¹) in N,N-dimethylacetamide (DMA), which feature lower critical solution temperatures (LCSTs). A fragment of the phase state diagram of the system PSF —PEG-400—PVP K-30—DMA was experimentally constructed in the following range of component concentrations: PSF 20–24 wt.%, PEG-400—35–38 wt.% and PVP—0–8 wt.%. It has been established that PVP addition substantially reduces the phase separation temperature down to 50–60 °C. Based on the obtained phase diagrams, a method for preparation of highly permeable hollow fiber membranes from PSF, which involves the processing of the dope solution at a temperature close to the LCST and the temperature of the bore fluid above the LCST, was proposed. Hollow fiber membranes with pure water flux of 1200 L·m⁻²·h⁻¹ and a sponge-like macrovoid-free structure were obtained via LCST-thermally induced phase separation by free fall spinning technique.