Fibers Of Different Origin Research Articles

Utilization of used textiles for solid recovered fuel production.

One of the current important issues is the management of used textiles. One method is recycling, but the processes are characterized by a high environmental burden and the products obtained are of lower quality. Used textiles can be successfully used to produce SRF (solid recovered fuels). This type of fuel is standardized by ISO 21640:2021. In the paper, an analysis of used textiles made from fibers of different origins was performed. These were acrylic, cotton, linen, polyester, wool, and viscose. A proximate and ultimate analysis of the investigated samples was performed, including mercury and chlorine content. The alternative fuel produced from used textiles will be characterized by acceptable parameters for consumers: a lower heating value at 20 MJ/kg (class 1-3 SRF), mercury content below 0.9 µg Hg/MJ (class 1 SRF), and a chlorine content below 0.2% (class 1 SRF). However, the very high sulfur content in wool (3.0-3.6%) and the high nitrogen content in acrylic may limit its use for power generation. The use of alternative fuel derived from used textiles may allow 3% of the coal consumed to be substituted in 2030. The reduction in carbon dioxide emissions from the substitution of coal with an alternative fuel derived from used textiles will depend on their composition. For natural and man-made cellulosic fibers, the emission factor can be assumed as for plant biomass, making their use for SRF production preferable. For synthetic fibers, the emission factor was estimated at the level of 102 and 82 gCO2/MJ for polyester and acrylic, respectively.

Magnetic resonance imaging-based classification of the myodural bridge complex and its influencing factors

Cerebrospinal fluid (CSF) circulation is considered the third circulation of the human body. Recently, some scholars have proposed the myodural bridge (MDB) as a novel power source for CSF flow. Moreover, the suboccipital muscles can exert a driving force on the CSF via the MDB. This hypothesis is directly supported by head rotation and nodding movements, which can affect CSF circulation. The MDB has been validated as a normal structure in humans and mammals. In addition, the fusion of MDB fibers of different origins that act in concert with each other forms the MDB complex (MDBC). The MDBC may be associated with several CSF disorder-related neurological disorders in clinical practice. Therefore, the morphology of the MDBC and its influencing factors must be determined. In this study, T2-weighted imaging sagittal images of the cervical region were analyzed retrospectively in 1085 patients, and magnetic resonance imaging (MRI) typing of the MDBC was performed according to the imaging features of the MDBC in the posterior atlanto-occipital interspace (PAOiS) and posterior atlanto-axial interspace (PAAiS). The effects of age and age-related degenerative changes in the cervical spine on MRI staging of the MDBC were also determined. The results revealed four MRI types of the MDBC: type A (no MDBC hyposignal shadow connected to the dura mater in either the PAOiS or PAAiS), type B (MDBC hyposignal shadow connected to the dura mater in the PAOiS only), type C (MDBC hyposignal shadow connected to the dura mater in the PAAiS only), and type D (MDBC hyposignal shadow connected to the dura mater in both the PAOiS and PAAiS). The influencing factors for the MDBC typing were age (group), degree of intervertebral space stenosis, dorsal osteophytosis, and degenerative changes in the cervical spine (P < 0.05). With increasing age (10-year interval), the incidence of type B MDBC markedly decreased, whereas that of type A MDBC increased considerably. With the deepening of the degree of intervertebral space stenosis, the incidence of type C MDBC increased significantly, whereas that of type A MDBC decreased. In the presence of dorsal osteophytosis, the incidence of type C and D MDBCs significantly decreased, whereas that of type A increased. In the presence of protrusion of the intervertebral disc, the incidence of type B, C, and D MDBCs increased markedly, whereas that of type A MDBC decreased considerably, with cervical degenerative changes combined with spinal canal stenosis. Moreover, the incidence of both type C and D MDBCs increased, whereas that of type A MDBC decreased. Based on the MRI signal characteristics of the dural side of the MDBC, four types of the MDBC were identified. MDBC typing varies dynamically according to population distribution, depending on age and cervical degeneration (degree of intervertebral space stenosis, vertebral dorsal osteophytosis formation, simple protrusion of intervertebral disc, and cervical degeneration changes combined with spinal canal stenosis, except for the degree of protrusion of the intervertebral disc and the degree of spinal canal stenosis); however, it is not influenced by sex.

Improving of an easy, effective and low-cost method for isolation of microplastic fibers collected in drying machines filters

Microplastic fibers have been found to be a dominant form of microplastics in water matrixes, and textile industry and domestic washing of synthetic textiles as one of its main sources. Additionally, there is a lack of knowlidge about microplastic fiber release during mechanically drying clothes and textiles due to differences in the isolation of microplastic fiber methods. Limited information available in the literature in terms of the isolation of microplastic fibers from organic-rich samples after using different household equipment represents one of the main challenges leading us to our main goal, to optimise an effective, simple, and low-cost method for the isolation of microplastic fibers from textile fibers of different origins without damaging their structure. This is achieved by primarily removing mineral matter by using density separation with a saturated solution of ZnCl2 followed by removal of organic matter by using hydrogen peroxide (H2O2) and FeCl3 as a catalyst. Identification of microplastic fibers was obtained by optical microscope, Fourier-transform infrared spectroscopy and Thermogravimetric analysis. Clear microscope (both optical and SEM) images, high percentage of obtained FTIR spectra overlap with Polymer Sample laboratory, clear TGA of isolated samples confirmed that this method can be used as a simple and effective method for isolation of microplastic fibers from organic components rich samples of different origin.

Artifacts in metallography: threads and fibers

Threads and fibers of different origin are considered as artifacts of sample preparation of metallographic sections, as well as samples of some materials. The role of various methods of optical contrasting – dark‑field illumination, polarized light – in the analysis of paper, natural and artificial fibers is illustrated. The presented materials can be used by materials scientists to identify errors in sample preparation, as well as to describe non‑traditional metallographic objects.

Analysis of Color Fastness and Shrinkage of Dyed and Printed Linen/Silk Fabrics

In this study, we analyzed the impact of the dyeing and the digital printing processes of linen/silk fabric (70% linen/30% silk) on its color fastness and shrinkage in the directions of warp and weft. This is a highly relevant topic because a single fabric combines two natural fibers of different origins—silk, a protein, is animal-based, whereas linen is derived from cellulose and is, thus, plant-based. Therefore, the different natures of the two fibers determine distinctive chemical properties. As a result, selecting the optimal technological course of processing for blended yarn fabrics and their yarn is a challenging task. The quality of the conducted finishing is determined by the physical properties of fabrics, such as color fastness to perspiration; soap; dry friction and wet friction; the pH of the fabric after finishing; and the shrinkage of the fabric in the directions of warp and weft. Here, color fastness was assigned the top grade with respect to all potentially harmful factors, except for wet friction. The evaluation proves that the technological regimes employed for digital printing and dyeing in the production item’s fabrics were properly selected.

FUNCTIONAL MATERIALS FROM WASTE PAPER. IV. COMPARATIVE STUDY OF FUNCTIONAL COMPOSITION, SUPRAMOLECULAR STRUCTURE AND MORPHOLOGY OF POWDER CELLULOSES ISOLATED FROM WASTE PAPER, PLANT CELLULOSES AND UNCONVENTIONAL RAW MATERIALS

A comparative study of the supramolecular structure, physico-chemical properties and morphology of powder celluloses (PCs) obtained from the waste paper of newsprint and cardboard, plant cellulose and unconventional raw materials was conducted using the methods of FTIR spectroscopy, high-resolution 13C NMR spectroscopy in the solid phase, wide-angle X-ray scattering and scanning electron microscopy (SEM). According to the results of FTIR and 13C NMR spectroscopy, the functional composition of PCs is similar to that of wood PCs and matches highly purified cellulose samples. The crystallographic structure of powder samples corresponds to the structure of cellulose I. The crystallinity and transverse dimensions of crystallites are 39.4% and 40.2% and 45 Å [110] and 54 Å [110] for PC from newsprint paper and cardboard, respectively. These values considerably exceed the analogous values for the initial waste paper samples. A comparative analysis of the SEM results showed a significant similarity of PCs fibers of different origin. The results of the study of the physico-chemical properties of PCs isolated from waste paper make it possible to predict their competitive application in comparison with plant PCs.

Traces of the absent: Evidence of textile production in the foothill region of jujuy, argentina (2000 AP)

Tropical environments present a constant challenge for archaeological research: the disappearance of hundreds of materials due to poor conditions for their preservation. In this case, the best examples are those materials connected to textile practices. Fibers of different origins are not expected to survive in such adverse conditions, since by their organic nature they are degradable. Nevertheless, differents elements implicated in the chaîne opératoire of production and the contexts in which they were used, can provide evidence that demonstrates the existence of the seemingly absent, and advance the knowledge of the technical aspects of this class of materials. Here, we present the findings of textile imprints in the valley regions of San Francisco (2000 BP) and analyze the implements that were used for their production, as well as ceramic representations that point to the possible use of these for clothing. The findings of imprints of knitted textiles that could have been made with yarns from Bromeliaceae family reveal the persistence of one class of textile that reaches from the hunter gatherer period (8000 BP) up to today among the populations of the Chaco and the Andean foothills.

The Middle Lamella of Plant Fibers Used as Composite Reinforcement: Investigation by Atomic Force Microscopy.

Today, plant fibers are considered as an important new renewable resource that can compete with some synthetic fibers, such as glass, in fiber-reinforced composites. In previous works, it was noted that the pectin-enriched middle lamella (ML) is a weak point in the fiber bundles for plant fiber-reinforced composites. ML is strongly bonded to the primary walls of the cells to form a complex layer called the compound middle lamella (CML). In a composite, cracks preferentially propagate along and through this layer when a mechanical loading is applied. In this work, middle lamellae of several plant fibers of different origin (flax, hemp, jute, kenaf, nettle, and date palm leaf sheath), among the most used for composite reinforcement, are investigated by atomic force microscopy (AFM). The peak-force quantitative nanomechanical property mapping (PF-QNM) mode is used in order to estimate the indentation modulus of this layer. AFM PF-QNM confirmed its potential and suitability to mechanically characterize and compare the stiffness of small areas at the micro and nanoscale level, such as plant cell walls and middle lamellae. Our results suggest that the mean indentation modulus of ML is in the range from 6 GPa (date palm leaf sheath) to 16 GPa (hemp), depending on the plant considered. Moreover, local cell-wall layer architectures were finely evidenced and described.

Forensic comparison of synthetic fibers

Polymeric fibers are one kind of trace evidence found in the crime scenes, and they play a crucial role in criminal investigation. Identification and comparison of polymeric fibers are a direct result of professional analysis. When performed properly, the analytical method used in differentiating fibers of different origins can be of high evidential value. Regular forensic examinations of synthetic fibers to determine type and subtype are based on microscopy, spectroscopy, chromatographic, and mass spectrometry. This review covers different analytical methods used in the forensic analysis and comparison of synthetic fibers. Copyright © 2015 John Wiley &amp; Sons, Ltd.

Complexity and health functionality of plant cell wall fibers from fruits and vegetables

ABSTRACTThe prevalence of lifestyle-related diseases is increasing in developing countries with the causes for death starting to follow the same pattern in the developed world. Lifestyle factors including inadequate dietary intake of fruits and vegetables and over consumption of nutrient-poor processed foods, are considered to be major causal risk factors associated with increased susceptibility to developing certain diseases (Alldrick, 1998; Kiani, 2007). Recent epidemiological evidence confirms a strong association between dietary fiber and reduced all-cause mortality risk, as well as a risk reduction for a number of non-communicable diseases (Chuang et al., 2012). The relationship between dietary fiber and mortality has been described as “convincing observations that call for mechanistic investigations” (Landberg, 2012). In particular, the health protective roles played by dietary fibers of different origin are not well understood. Whilst Hippocrates was the earliest known physician to study the health benefits of fiber derived from grains (Burkitt, 1987), the functionality of fruit and vegetable fiber, especially in association with other compounds such as polyphenols and carotenoids, is an area of more recent interest. Hence the objective of this review is to assess the complexity and health-related functional role of plant cell wall (PCW) fibers from fruits and vegetables with a particular emphasis on interactions between cell walls and phytonutrients.

Determination of Cellulose Fiber Structure Using IR Reflectance Spectroscopy of Paper

A rapid and non-destructive method for analyzing the structure of cellulose fibers using IR reflectance spectroscopy from a paper surface was developed and verified for correctness. IR absorption and reflectance spectra of standard paper samples of known composition (sheets made of four fibers of different origin without additives and with additives of kaolin and chalk) were analyzed. Good correlations between these two spectral methods were found for the studied samples. Calibration curves were useful for assessing the structure of cellulose samples from XVIth century historical paper. Data on the degree of cellulose ordering that were obtained from the paper reflectance spectra indicated that the studied sheets consisted mainly of flax fibers with added cotton. This agreed fully with the historical fact that the studied samples were rag papers.

Forebrain projections to the hypothalamus are topographically organized in anurans: conservative traits as compared with amniotes

The organization of the forebrain in amphibians (anamniotes) is currently being re-evaluated in terms of evolution and several evidences have corroborated numerous traits shared by amphibians and amniotes, such as the organization of the basal ganglia and the amygdaloid complex. In the present study we have analysed the organization of forebrain afferent systems to the hypothalamus of the frog Rana perezi. In vivo and in vitro tract-tracing techniques with dextran amines and immunohistochemistry for localizing nitric oxide synthase (NOS) in a series of single or combined experiments were used as NOS labelling reveals hypothalamic afferents arising from the lateral amygdala and the combination allowed analysis of the relationship between fibers of different origins in the same section. The results showed a large segregation of afferents in the hypothalamic region depending on their site of origin in the forebrain. Four highly topographically organized prosencephalic tracts reaching the anuran hypothalamus were observed: (i) the medial forebrain bundle, from the medial pallium and septal complex; (ii) the caudal branch of the stria terminalis formed by fibers arising in the lateral and medial amygdala; (iii) part of the lateral forebrain bundle with fibers from the central amygdala and (iv) the dorsal thalamo-hypothalamic tract. Fibers coursing in each tract reach the hypothalamus and terminate in distinct fields. The resemblance in pattern of forebrain-hypothalamic organization between amphibians and amniotes suggests that this feature represents an important trait conserved in the evolution of all tetrapods and therefore essential for the hypothalamic function.

Characterization of the crystalline structure of cellulose using static and dynamic FT-IR spectroscopy

The cellulose structure is a factor of major importance for the strength properties of wood pulp fibers. The ability to characterize small differences in the crystalline structures of cellulose from fibers of different origins is thus highly important. In this work, dynamic FT-IR spectroscopy has been further explored as a method sensitive to cellulose structure variations. Using a model system of two different celluloses, the relation between spectral information and the relative cellulose I α content was investigated. This relation was then used to determine the relative cellulose I α content in different pulps. The estimated cellulose I allomorph compositions were found to be reasonable for both unbleached and bleached chemical pulps. In addition, it was found that the dynamic FT-IR spectroscopy technique had the potential to indicate possible correlation field splitting peaks of cellulose I β.

Composites made from acetylated lignocellulosic fibers of different origin

Composites made from acetylated lignocellulosic fibers of different origin

Composites made from acetylated lignocellulosic fibers of different origin

Lignocellulosic fibers of different origins were acetylated in large batches. The fibers used were of commercial, medium density fiberboard (MDF) pulp quality produced from softwood, beech, waste wood (low quality residue from an intermediate forest cutting) and wheat straw, respectively. Fiber from de-inked, semi-bleached, recycled paper was also included in the study. Laboratory fiberboards were produced from the acetylated fibers by using powdered phenolic resin of the novolak type as a binding agent. Control boards made from unmodified fiber were also produced. The fiberboards were subjected to mechanical and dimensional stability testing. The acetylation of the fiber, regardless of the source of the lignocellulosic material, has a very positive impact on the performance of fiber composite products. For instance, the thickness swelling for softwood fiberboard in water is reduced by approximately 90%, and the mechanical properties are slightly improved. Results from cyclic testing according to EN 321, (three cycles, each comprising 72 h water immersion, 24 h freezing at -18°C and 72 h drying at 70°C) show that more than 90% of the internal bond strength, IBS, remained after the testing. This value can be compared with the corresponding value of 30-40% obtained for fiberboards made from unmodified fibers. The remaining thickness swelling of fiberboards made from acetylated fibers was independent of fiber source and resin content. The results obtained showed that acetylation can improve the mechanical properties of fiberboards provided that a proper resin is chosen.

Composites made from acetylated lignocellulosic fibers of different origin

Conventional technology for manufacturing nonwoven fiber mats for the production of complex shaped fiber composite products involves a needling step in which textile fibers are entangled with lignocellulosic fibers coated with a thermosetting resin. The technique used in this project for the production of nonwoven fiber mats involves bicomponent thermoplastic fibers that, upon heating and subsequent cooling, form an elastic network together with the lignocellulosic fibers. Powdered phenolic resin of the novolak type was added to the mat forming step. The main objectives of this study were : to investigate how the composition of the fiber mat affects molding ability, and to ensure that the benefits of acetylation, i.e., the dimensional stability of the molded product, remain. An experimental design was used to evaluate the effects resulting from the following factors : the type of lignocellulosic fiber, with or without the acetylation of lignocellulosic fiber, the type and concentration of thermoplastic fiber. The lignocellulosic fibers examined were softwood, aspen, wheat straw, beech, waste wood and recycled paper fiber. The presence of thermoplastic fibers has no negative effect upon the improvement of dimensional stability obtained by acetylation. Both the concentration level and type of thermoplastic fiber had a great impact on the tensile strength of the fiber mat and its molding ability. Aspen and softwood fiber mats showed good results, even at a low thermoplastic content. It was shown that provided the proper type and concentration of thermoplastic fiber are chosen, a wide variety of lignocellulosic fibers can be used to produce fiber mats with good molding ability.

The urodelean Mauthner cell. Morphology of the afferent synapses to the M-cell of larvalSalamandra salamandra

In the present work the fine morphology and the distribution of the afferent synapses to the Mauthner cell of larvalSalamandra salamandra are described. The aim of the study is to characterize the synaptic bed in the larvae of this terrestrial salamander in order to compare it with that of larval axolotl and larval anurans. Four main types of afferent endings have been identified: myelinated club endings, roundvesicle end bulbs, flattened-vesicle end bulbs and spiral fibers endings, which probably correspond to afferent fibers of different origin. TheM-cell afferent synaptology of larval stages of terrestrial amphibians is quite similar to that previously observed in larval stages of aquatic species. This fact can be related to the fundamental similarities between the larval lifestyles.

Crystallinity and lateral crystallite size of different UHMW PE materials

AbstractNascent high‐molecular‐weight (UHMW) polyethylene (PE) samples of different origins show a rather high crystallinity of about 70–75% and contain both a major portion of orthorhombic extended chain crystallites and a minor portion of triclinic crystallites. The triclinic content is greater the higher the molecular weight of the sample and the higher the activity of the used catalyser. A melting / recooling treatment results in a reduction of crystallinity by about 15–25% and disappearance of the triclinic phase. Further, an irreversible conversion of nascent orthorhombic extended chain crystallites to orthorhombic folded chain crystallites of increased lateral dimensions and crystalline perfections takes place during the melting / recooling treatment. The results are compared to those obtained for lower‐molecular‐weight PE samples and for high‐strength / modulus PE fibers of different origins.

Relative effectiveness of C primary afferent fibers of different origins in evoking a prolonged facilitation of the flexor reflex in the rat

Changes in the excitability of the hamstring flexor withdrawal reflex produced by conditioning stimuli applied to C-afferent fibers of different origins have been examined in the decerebrate spinal rat. In the absence of conditioning stimuli, the flexor reflex elicited by a standard suprathreshold mechanical stimulus to the toes is stable when tested repeatedly for hours. Three categories of conditioning stimuli have been used in an attempt to modify the excitability of the flexor reflex; electrical stimulation of a cutaneous (sural) nerve or a muscle (gastrocnemius-soleus) nerve at C-fiber strength; the application of mustard oil, a chemical irritant that activates chemosensitive C-afferents, to the skin or injected intramuscularly and intraarticularly; and the indirect activation of high-threshold muscle afferents by fused tetanic contractions of the tibial muscles. Conditioning stimuli of an intensity sufficient to activate C-afferent fibers result in a heterosynaptic facilitation of the flexor motoneuronal response to the standard test input, which lasts from 3 min to more than 3 hr, depending on the stimulus and the C-afferents activated. Pretreatment of the sciatic nerve with the C-fiber neurotoxin capsaicin abolishes all the postconditioning facilitations, which is an indication that it is likely that it is C-afferents that are primarily responsible for the facilitatory effects of the conditioning stimuli, although some A delta afferents may contribute. Capsaicin pretreatment does not modify the reflex response to the test stimulus. The most prolonged increase in the excitability of the flexor reflex resulted from intraarticular injections of 5 microliter mustard oil. Using the subsequent injection of lignocaine intraarticulary, it was found that the prolonged facilitation of the reflex is triggered by the afferent input generated by the conditioning stimulus and does not require an ongoing input for its maintenance. These results indicate that there is a spectrum of central changes in the stimulus response relations of the spinal cord resulting from the activation of C-fibers of different origins. The prolonged duration of some of these changes means that the peripheral activation of C-afferents will modify the functional response of the spinal cord to other inputs applied long after the conditioning input, and this may be responsible for some of the sensory and motor alterations found after peripheral tissue injury.

Serotonergic innervation of cat cerebral arteries

5-HT and 5-HIAA were measured in cat cerebral arteries by HPLC. Removal of both superior cervical ganglia or simultaneous lesions of dorsal and central raphe nuclei significantly decreased 5-HT levels but not those of 5-HIAA. This suggests that cat cerebral blood vessels are innervated by serotonergic fibers of different origin.