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Yarn’s hairiness represents a continuous challenge for spinning technologies. To keep this aspect under control, an almost perfect combination between the construction and performance of the machines, the control of the technological processes through appropriate settings, and the experience of the producers are required. As a consequence, the researchers were preoccupied to adapt or modify the ring frame to produce yarns with a lower degree of hairiness. Spinning triangles as a very demanding area exert a crucial impact both on the distribution of fiber tension and their spatial location in the staple yarn structure. Our study encompasses yarn hairiness reduction employing a device composed of two bars. Various combinations of spindle speeds and contact angles between yarns and bars were tested to examine their effects on yarn hairiness. The study was completed with the optimization of technological parameters using a central, composite, rotating program with two independent variables (spindle speed and contact angle) to establish mathematical models and optimize technological parameters for the reduction of hairiness. The effectiveness and efficiency of this device consist of the easy execution and installation on the existing machines in spinning mills without any constructive adjustments and additional energy consumption.

Elevated carbon dioxide and drought are significant stressors in light of climate change. This study explores the interplay between elevated atmospheric CO2, drought stress, and plant physiological responses. Two Brassica oleracea varieties (cauliflowers and cabbage) were utilized as model plants. Our findings indicate that elevated CO2 accelerates assimilation rate decline during drought. The integrity of photosynthetic components influenced electron transport, potentially due to drought-induced nitrate reductase activation changes. While CO2 positively influenced photosynthesis and water-use efficiency during drought, recovery saw decreased stomatal conductance in high-CO2-grown plants. Drought-induced monoterpene emissions varied, influenced by CO2 concentration and species-specific responses. Drought generally increased polyphenols, with an opposing effect under elevated CO2. Flavonoid concentrations fluctuated with drought and CO2 levels, while chlorophyll responses were complex, with high CO2 amplifying drought’s effects on chlorophyll content. These findings contribute to a nuanced understanding of CO2–drought interactions and their intricate effects on plant physiology.

The present paper focuses on the colour changes of freshly peeled/sliced fruits by using vacuum-impregnation of the apple slices with freshly prepared fruit juice and their mixture with two types of honey with the role of inhibition of the enzymatic browning of the apples. These syrups have the advantage of inhibiting the enzymatic browning of the fruits due to their high content of organic acids. The change in the colour of the fruits was monitored by using a colorimetric system, CIELAB. The obtained results were used to identify the best vacuum-impregnation solution for the preservation of the apple slices that can be marketed.

Climate change will determine a sharp increase in carbon dioxide in the following years. To study the influence of elevated carbon dioxide on plants, we grew 13 different species and varieties from the Brassicaceae family at three carbon dioxide concentrations: 400, 800, and 1200 ppmv. The photosynthetic parameters (assimilation rate and stomatal conductance to water vapor) increase for all species. The emission of monoterpenes increases for plants grown at elevated carbon dioxide while the total polyphenols and flavonoids content decrease. The chlorophyll content is affected only for some species (such as Lipidium sativum), while the β-carotene concentrations in the leaves were not affected by carbon dioxide.

The research aim was to determine the pretreatment (scouring and bleaching) method's influence on 100 % cotton materials dyeing. Before bleaching treatments, the fabrics' non-cellulosic attendants were removed during a pectinolytic treatment and classic alkaline treatment. The general idea of the investigation was maintained in all stages approached, so in addition to the alkaline treatment, an enzymatic treatment was performed (bioscouring) where the classical chelating agent, EDTA, was replaced with sodium citrate. Further, the fabrics were bleached using hydrogen peroxide or a green one, enzymatic, with laccase. A commercial reactive dye was used to colour the cotton samples. The efficiency of the treatment was determined by following the dye fixation degree through soaping. The weight loss, hydrophilicity, tensile strength, elongation at break and colorimetric measurements were used to analyse the treated samples. The higher weight loss values of ~ 5% were found for the alkaline scoured sample and alkaline scoured sample followed by hydrogen peroxide bleaching which also showed the lowest value for tensile strength (259.90 N). Hydrophilicity was less than 3 seconds for all treatments. The 100% dye fixation degree was obtained for the bioscoured sample and bleached with H2O2. Even if the eco-friendly treatments proposed as an alternative for classical scouring and bleaching lead to similar or lower results, some of their advantages should be considered: environmentally friendly, lower costs, a lower fibre damage degree, etc. All these procedures use a lower temperature, respectively, fewer quantities of reagents and are not significantly aggressive with the environment. [ABSTRACT FROM AUTHOR]

The paper presents a comparative study of the behaviour of 97% polyamide/3% elastane socks, named functional socks, and of 70% cotton/27% polyamide/3% elastane socks, called classic socks, both type used for moderate-intensity physical activity. Nowadays, the question always arises about what socks to wear: classic 100% cotton socks, cotton/polyamide/elastane socks, or polyamide/elastane socks. The wearing comfort of the socks is the determining factor in choosing the optimal variant. The functional socks are made of 100% synthetic yarns and are appreciated due to the properties of absorption and rapid transfer of moisture from the body to the environment. The classic socks are made of cotton or cotton yarns mixed with synthetic yarns, giving better wearing comfort compared to functional socks through the high moisture absorption capacity. But due to the small capacity to transfer moisture from the body to the outside environment, wearing for a long time can produce discomfort as a result of the humid environment that is created. The two types of socks were evaluated through a series of analyses as follows: weight per piece, optical microscopy, hygroscopicity, hydrophilicity, elasticity in the direction of stitches' rows and degree of compression. The analysed data led to the conclusion that functional socks have superior elasticity and comfort properties compared to the classical ones. [ABSTRACT FROM AUTHOR]

The paper presents a study of the behaviour of rib 1:1 and 2:2 knitted fabrics made of 100 % cotton yarns during different solicitations and treatments. The studied knits were grey and finished fabrics obtained on large circular knitting machines in the form of tubular metreage. Grey knitted fabrics were deposited for relaxation, 72 hours in folded condition, in an air-conditioned room in accordance with standard atmosphere parameters. After relaxation, the knits were finished in regular factory parameters and optically brightened. Several aspects were analyzed, namely: vertical density and the mass per square meter; the tesile strength in the direction of the rows of stitches, hydrophilicity and whiteness degree. For grey rib 1:1 and 2:2 knitted fabrics, the vertical density after relaxation increases by 60 % compared to the vertical density on the knitting machine. By finishing, the values of vertical density have almost double values compared to the vertical density on the knitting machine. The established vertical density on the knitting machine is decisive for the mass per square meter, the dimensional stability and the shape after several cycles of wear and washing. The rib 2:2 structures combine elements specific for plain and rib knitted fabrics, which is why they are less balanced in terms of internal tensions. Because of that, this structure behaves differently than rib 1:1 structure during the tensile strength solicitations. The applied Uvitex BLH optical brightener gives to the cotton knitted fabrics an eminent appearance which is called whiter than the whites. [ABSTRACT FROM AUTHOR]

The main objective of the pretreatments applied in textile industry is to remove all native impurities present in the natural fibers. The nature and quantity of noncellulosic compounds present in hemp and cotton fibers is variable. These have hydrophobic characteristics which negatively influence the fabrics hydrophilicity. Depending on their nature these can be eliminate by a simple wash procedure or if we think at those of chemical nature more advance methods need to be performed. In the study, the result obtained after applying a bioscouring treatment on 50 % of hemp-50 % of cotton blended fabrics are presented. The aim of the procedure was the elimination of physical and chemical compounds presented in the fabric for the improving of its technological characteristics. A pectinolytic commercial product (Beisol PRO) was used, varying its concentration. The reaction bath contained phosfate buffer solution of 0.1 M and pH 8, 2 g/L complexing agent (EDTA) and 0.5 % surfactant (Denimcol Wash RGN). The bioscouring treatments were performed using a central, rotatable second order compound program with two independent variables: Beisol PRO concentration (between 1-3 % o.w.f) and exposure time (15-55 minutes) at 55°. The liquid to faric ratio was 20:1. The following parameters were determined: weight loss, hydrophilicity, calcium content, whiteness and yellowness index. The obtained results underline the efficiency of the considered method. The pectinolytic procedure applied on the hemp-cotton materials has contributed to pectin hydrolysis and optimum removal of undesired impurities with minimum fabrics degradation. [ABSTRACT FROM AUTHOR]

Natural fibres are subjected to scouring treatment in order to remove different impurities like waxes, organic acids, pigments and pectins. Pectines are found in the plant cell walls. From the chemical point of view are polysaccharides. The modern trends in different industrial sectors are based on the utilisation of eco friendly treatments to remove them. In our case, the classical alkaline procedure was substituted by an enzymatic one. On 100 % of cotton samples were applied different bioscouring treatments with a pectinases mixture in different conditions. All the bioscouring treatments were developed in presence of ultrasound (45 KHz). The reaction bath contained a commercial pectinolytic product, a complexing agent and a washing agent. There were used diffent enzyme concentratios and the treatment time was variable. To determine the samples behavior toward the enzymes action, the residual pectin was quantified. Ruthenium red dye was chosen since it is considered to be a specific one for binding pectin presented in the fibres. The measurements were done spectrophotometrically with a Datacolor 500 spectrophotometer and the colour strength ratio [K/S] was obtained by measuring the reflectance at 530 nm. The results obtain in case of each treatment were compared with the one determined for the untreated sample, which was considered to have the highest amount of pectin. [ABSTRACT FROM AUTHOR]

Impact of economic development - ecological balance rises numerous and complex problems for the textile industry. It is known that all textile processes need important quantities of water and chemicals. This situation generates large amounts of wastewater which cannot be further use without additional treatments because of the environmental problems. The issue of environmental protection has become an essential part of the textile industry development strategy. Many studies in the field present alternatives for the conventional scouring to reduse water pollution. The applied ecological strategy is focused on process optimization and pollution prevention. The paper presents a comparison of the physico-chemical parameters of the wastewater resulted from the various scouring treatments applied on a cotton/hemp fabric. Three types of scouring treatments have been carried out: two with enzymes for which a commercial enzyme product, a washing agent and EDTA or sodium citrate as complexing agents were used, and one classical scouring treatment with sodium hydroxide. The main physico-chemical parameters of the residual water analyzed were: pH, salinity, turbidity, TDS (total dissolved solids), conductivity, chemical oxygen demand (CCOMn), total dissolved oxygen and dry residue. From the two enzymatic treatments, the values of physico-chemical parameters of the residual water were in accordance with the legislation in case were the sodium citrate was used. For the alkaline treatment, the data were even with 100 % higher compared to enzymatic treatments. For some parameters, higher values were registered also for the enzymatic scouring where EDTA was used as a complexing agent. [ABSTRACT FROM AUTHOR]

This study shows a comparative characterization of whitening treatment using various processes for 60 % cotton +40 % hemp materials scoured by Bioscouring treatment in ultrasound described in our previous work. The results of the extraction of noncellulosic impurities using the Bioscouring treatment was expressed as weight loss, hydrophilicity. Some of these bio-scoured samples were whitened using various procedures: Classical procedure with hydrogen peroxide (30%), with catalyst and with laccase enzyme. By whitening procedure, the double bonds from chromophore groups of natural pigments from cotton and hemp are destroyed by oxidation reactions, the ? electrons being those responsible for the yellow color of the fabrics. In order to characterize the quality of the enzymatic pretreatment compared to the classical one, the values of the degree of white were studied after different type of bleaching (hydrogen peroxide, catalyst and laccase) for the samples treated with the same concentration of enzyme SERA ZYME C-PE (ROGLYR ECO 183) - Pectate Lyase. For comparing the degradation occurred during the enzymatic preatreatment of cellulosic fabrics, before and after bleaching with enzymes, catalyst and classical method, measurements of the tensile strength and elongation at break for the treated 60 % cotton +40 % hemp material, were performed. [ABSTRACT FROM AUTHOR]

The paper presents the optimization of the Bioscouring treatment in ultrasound on 60 % cotton + 40 % hemp materials, using the commercial product SERA ZYME C-PE (Roglyr Eco 183), based on 5-15 % Pectate Lyase (E.C.4.2.2.2). In order to assess more accurately the influence of some process parameters of the BIOSCORING treatment in ultrasound of 40 % hemp + 60 % cotton blended fabric - the concentration of enzyme (%) and treatment time (minutes) - on the weight loss, a mathematical modeling of the process was made, using a central compound rotatable program with two independent variables. The Bioscouring treatment was performed in ultrasound under the following conditions: (1-3 %) SERA ZYME C-PE (ROGLYR ECO 183) - Pectate Lyase; 2 mL/L HEPTOL NWS - sequestrant agent which have a binding role for the metal ions in water with high hardness, regardless of temperature; 2 mL/L SULFOLEN 148 - wetting and scouring agent; 10 % of the fleet of treatment was buffer (0.1 Molar sodium phosphate/disodium phosphate, pH = 7.5); liquid to fabric ratio - H 10:1, at temperature T = 55 °C and time - t = (20-60) minutes. Using the data obtained by measuring the weight loss, the optimum working parameters for the Bioscouring treatment in ultrasound with commercial enzyme SERA ZYME C-PE (ROGLYR ECO 183) were determined. [ABSTRACT FROM AUTHOR]