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The potential for sustainable lignocellulosic agro-waste is immense, owing to the fact that it represents the most abundant organic compound on Earth. It is a valuable and desirable source for material production across numerous industries due to its abundance, renewability, and biodegradability. This paper explores the world of barley fibers, which are extracted from the straw of two different cultivars (old Rex or new Barun) and have tremendous potential for use, primarily for technical textiles. The quantity of the extracted fibers depends both on the type of barley used and on climate conditions that influence the plants’ growth, resulting in fiber yields ranging from 14.82% to 19.59%. The chemical composition of isolated fibers revealed an optimal content of cellulose and lignin in barley fibers isolated from the Rex variety. Those results were confirmed with FTIR analysis, which revealed a lower intensity of peaks associated with hemicellulose and lignin and, therefore, indicated their better removal after the chemical maceration process. In terms of fiber density, the quality of the fibers was comparable to that of cotton fibers, but they differed significantly in moisture regain (10.37–11.01%), which was higher. Furthermore, sufficient fiber tenacity (20.31–23.08 cN/tex) was obtained in a case of old-variety Rex, indicating the possibility of spinning those fibers into yarns, followed by their extended usage for apparel. Additionally, our paper reveals the possibility of fulfilling the requirements of the zero waste principle due to the fact that a high percentage of solid waste left after the fiber extraction (26.3–32.3%) was afterwards successfully used for the production of biofuels, enabling the closing of the loop in a circular economy.

Spanish Broom (Spartium junceum L.) is a Mediterranean plant of various usage possibilities. Its fibres were known since ancient time but in some point of last century, more accurately in 1950s, their production was abandoned due to the negative economic effect. Another drawback was large time consumption, especially during the old tradition method – Spanish Broom maceration in salt water. Nowadays, due to technology development and ecological awareness, it is much easier to produce Spanish Broom fibres of enhanced quality. One of the fibre extraction methods is the one assisted with microwave oven. Demerit of such fibre production is in large residue content after obtaining fibres - approx. 90 % of initial Spanish Broom weight. Due to the need for finding sustainable solutions in the development of new materials, the usage of Spanish Broom fibres in the service of reinforcement for biopolymer poly (lactic acid) (PLA) matrix was investigated. Obtained results target our further research into the direction of Spanish Broom fibres and PLA application in the production of green composites. The aim of this research was to prove that developed product can be categorized under the biodegradable group by investigating its degradation properties using serine endopeptidase enzyme. The results show positive degradation effect while using 50 wt.% (on weight of material) enzyme concentration during a 5-day treatment. Stem residues of Spanish Broom plant derived from salty water and microwave maceration were further investigated for their potential as raw material for second-generation biofuel production. Examination of its energy properties consisted of determination of proximate and ultimate properties of the biomass. The results show low moisture content (6.5 % - 7.5 %), ash content below 5 % and higher values of fixed carbon and volatile matter content of 13.2 % and 75 %, respectively. Higher heating values that were determined (17.2 - 18.8 MJ/kg) indicate a high quality biomass that can be used most effectively in solid biofuel production.

Different chemical pre-treatments of Spartium junceum L. fibres using alkali (NaOH), nanoclay (MMT) and Citric acid (CA) with the aim of producing biodegradable composite material are discussed. As environmental requirements in processing technologies have been higher in recent years, the Polylactic acid (PLA) is used in this research as a matrix, due to its renewability, biodegradability and biocompatibility. Biocomposites are prepared by reinforcing PLA with randomly oriented, short Spartium junceum L. fibres in order to increase material strength. The effects of different pre-treatments of Spartium junceum L. fibres on the mechanical properties of final biocomposite material are examined. Fibre tenacity is studied using Vibroscop and Vibrodyn devices. Tensile strength of biocomposite material was measured on the universal electromechanical testing machine Instron 5584. The results indicate that biocomposites reinforced with fibres modified with MMT and CA show upgraded mechanical properties of the final composite material in comparison with the composite materials reinforced with referenced (nontreated) fibres. Infrared spectra of tested fibres and biocomposites were determined with Fourier transform infrared spectroscopy using Attenuated total reflection (FT-IR ATR) sampling technique and the influence of fibre modifications on the fibre/polymer interfacial bonding was investigated. The interface of Spartium/PLA composites was observed with scanning electron microscope (SEM) and it was clearly visible that biocomposites reinforced with fibres modified by MMT and CA showed better interaction of fibres and matrix. Keywords: Fibres, Polymer-matrix composites (PMCs), Mechanical properties, Mechanical testing

Environmentally benign layer-by-layer (LbL) deposition was used to obtain flame-retardant and antimicrobial cotton. Cotton was coated with 8, 10, and 12 phytic acid (PA) and chitosan (CH)-urea bilayers (BL) and then immersed into copper (II) sulfate (CuSO4) solution. Our findings were that 12 BL of PA/CH-urea + Cu2+ were able to stop flame on cotton during vertical flammability testing (VFT) with a limiting oxygen index (LOI) value of 26%. Microscale combustion calorimeter (MCC) data showed a reduction of peak heat release rates (pHRR) of more than 61%, while the reduction of total heat release (THR) was more than 54%, relative to untreated cotton. TG-IR analysis of 12 BL-treated cotton showed the release of water, methane, carbon dioxide, carbon monoxide, and aldehydes, while by adding Cu2+ ions, the treated cotton produces a lower amount of methane. Treated cotton also showed no levoglucosan. The intumescent behavior of the treatment was indicated by the bubbled structure of the post-burn char. Antibacterial testing showed a 100% reduction of Klebsiella pneumoniae and Staphylococcus aureus. In this study, cotton was successfully functionalized with a multifunctional ecologically benign flame-retardant and antibacterial nanocoating, by means of LbL deposition.

Small wooden samples of fir (Abies alba Mill.) and beech (Fagus sylvatica L.) were chemically modified by citric acid (CA) as non-formaldehyde cross-linking system reagent and cured by convection heating at three different temperature regimes. Two different CA solutions were used, one with NaH2PO2 and the other with NaH2PO4 as a catalyst. The dimensional stability of the modified wood was determined by the anti-swelling efficiency (ASE) using the water soak/oven dry method. Almost equally large improvement of dimensional stability of wood was attained using NaH2PO4 as when NaH2PO2 was applied as a catalyst.

In dem vorliegenden Beitrag geht es um das Verhältnis von schulischen Mentor*innen und Lehrkräften im Vorbereitungsdienst (LiV) und die Konsequenzen einer möglichen widersprüchlichen Beziehung. Auf Basis eines Unterrichtsnachgespräches zwischen einem Mentor und einer LiV werden in einer sequenziellen Analyse verschiedene Formen der Kritikäußerungen expliziert, die in letzter Konsequenz eine Kritik ohne Kritik evozieren.

After a long break, Spanish broom gained interest as a natural, sustainable and renewable fibre for textile and technical applications. This paper describes the characterization of Spanish broom fibres (Spartium junceum L.) in comparison to the flax fibres (Linum usitatissimum). Spanish broom fibres were obtained by two different methods of maceration and some of the most significant chemical and physical properties of tested fibres are reported. Scanning electron microscopy has proven to be a useful tool for the determination of morphological characteristics of elementary and technical fibres. Other physical-chemical properties of fibres were determined by infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), fineness and tensile strength methods. [ABSTRACT FROM PUBLISHER]

Aim To study the antimicrobial activity of citric acid (CA) and sodium hypophosphite monohydrate (SHP) against gram-positive and gram-negative bacteria, and to determine the influence of conventional and microwave thermal treatments, on the effectiveness of antimicrobial treatment of cotton textiles. Method Textile material was impregnated with CA and SHP solution and thermally treated by either conventional or microwave drying/curing treatment. Antibacterial effectiveness was tested according to ISO 20743:2009 standard, using absorption method. The surfaces were morphologically observed by scanning electron microscopy, while physical characteristics were determined by wrinkle recovery angles method (DIN 53 891), tensile strength (DIN 53 837), and whiteness degree method (AATCC 110-2000). Results Cotton fabric treated with CA and SHP showed significant antibacterial activity against MRSA (6.38 log10 treated by conventional drying and 6.46 log10 treated by microwave drying before washing, and 6.90 log10 and 7.86 log10, respectively, after 1 cycle of home domestic laundering washing {HDLW]). Antibacterial activity was also remarkable against S. oureus (4.25 log10 by conventional drying, 4.58 log10 by microwave drying) and against P. aeruginosa (1.93 log10 by conventional drying and 4.66 log10 by microwave drying). Antibacterial activity against P. aeruginoso was higher in samples subjected to microwave than in conventional drying. Antibacterial activity was reduced after 10 HDLW cycles but the compound was still effective. The surface of the untreated cotton polymer was smooth, while minor erosion stripes appeared on the surfaces treated with antimicrobial agent, and long and deep stripes were found on the surface of the washed sample. Conclusion CA can be used both for the disposable (non-durable) materials (gowns, masks, and cuffs for blood pressure measurement) and the materials that require durability to laundering. The current protocols and initiatives in infection control could be improved by the use of antimicrobial agents applied on cotton carbohydrate polymer. [ABSTRACT FROM AUTHOR]

Copyright of Tekstil: Journal of Textile & Clothing Technology is the property of Croatian Association of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tekstil: Journal of Textile & Clothing Technology is the property of Croatian Association of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fibres & Textiles in Eastern Europe is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper describes our research of microwave usage in drying the size pick-up. An analysis of three different drying processes in relation to physical-mechanical properties of sized yarn has been carried out. Under the same sizing conditions, but different drying methods, the following parameters were determined: breaking force, elongation at break, abrasion resistance and yarn hairiness. The application of microwave drying method for warp sizing showed to be equally good, or even better in some cases, compared to the conduct and convection drying methods. [ABSTRACT FROM AUTHOR]

Copyright of Tekstil: Journal of Textile & Clothing Technology is the property of Croatian Association of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Faculty of Textile Technology (TTF) University of Zagreb has realized the significance of early involvement of its employees into the EU projects and by establishing Service for Textile European Projects (STEP) has made a significant step towards coordination of this activity. Main objective of STEP is giving support to TTF's employees, as well as to partners from industry, For preparation of international project proposals, education of EU project managers and inclusion of Croatian textile science and industry into the EU processes. This paper presents participation of TTF in the European Technology Platform for the future of textiles and clothes in the framework of projects. The European Apparel and Textile Organisation (EURATEX) has recently established new Textile Project Proposal Information Exchange System (TEPPIES). The most important task of STEP is initiation of project proposals which has increased after the establishment of STEP,so as with the participation in TEPPIES. [ABSTRACT FROM AUTHOR]

Copyright of Tekstil: Journal of Textile & Clothing Technology is the property of Croatian Association of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wood specimens of fir (Abies alba Mill) and beech (Fagus sylvatica L.) were chemically modified using polycarboxylic acids (PCA), cured by convection heating or microwave treatment and analyzed by HPLC. A new non-formaldehyde cross-linking system was composed of citric acid (CA) and 1,2,3,4-butanetetracarboxylic acid (BTCA), which are representative polycarboxylic acids (PCAs). These reagents require phosphono-based catalysts, so a sodium hypophosphite (SHP) catalyst was used in this study. The effects of PCA treatment were compared with a previously introduced 1,3-dimethylol 4,5-dihydroxy ethylene urea (DMDHEU) treatment. The dimensional stability of the modified wood was determined in terms of the anti-swelling efficiency (ASE) using the water soak/oven dry method. The results revealed an improvement in ASE for wood modified with PCA compared to modification with DMDHEU. Qualitative and quantitative determinations of bound acids were performed by HPLC. Further intensification of the wood modification process and an increase in the quality of wood-based materials were achieved using microwave treatment. Among other benefits, the formation of cross-links between the wood and the reagent components led to an improvement in the tensile strength retention, particularly in combination with the microwave treatment. [ABSTRACT FROM AUTHOR]

Presents a study which used microwave energy to impart durable crease resistance to dyed cotton fabric. Importance of microwave and radio frequency technologies to industrial heating, drying and curing; Statistical data of the linear regression analysis; Results and discussion.