Investigating the Effects of Particle Size on the Growth of Silkworm and Fiber Properties with Feeding TiO2 NPs

The production method of functional silk by feeding the various nanoparticles is simple, it has attracted the attention of many researchers. However, many researchers have studied the concentrate of nanoparticles (NPs), there are few studies on the particle size. This study is aimed to confirm the effects in silkworm growth, cocoon quality, and mechanical properties of silk with feeding TiO2 NPs of the various particle size. TiO2 10nm, 50nm, 100nm powers individually are fed to silkworm, investigated the mortality and proliferation rate, cocoon mass and cocoon shell mass, mechanical characteristic of silk fiber. The experiments demonstrated that the larger the particle size of TiO2 NPs, the greater the adverse impact on the growth and livability of silkworms. The stress of 523.35±42 MPa and strain of 19.73±1.8% of the TiO2-10nm added silk were increased 35.9% and 19.5% on average, respectively. By the analysis of the Fourier transform infrared (FTIR) spectra, it was confirmed that this resulted in a more random coil/?-helix structure. The nanoparticles are acted as knots, forming the cross-linked network, resulting in lower crystallinity and higher strain, but the larger the particle, the fewer the number of knots, at the same time, it has a great impact on protein synthesis, and then the strength may be decreased. The effect in the silkworm body of TiO2 NPs particle size has to be deeply studied, but this study has important significance to study in the production of the functional silk by feed additives.

Study on the influence of the cotton storage process on the quality indicators of fiber and yarn

This article defines fiber quality indicators that differ in laboratory conditions from the upper, middle and lower layers of Bukhara-6 breeding varieties of cotton, in the modern system HVI 1000 SA. Based on the results of the study, histograms of changes in the quality of cotton fiber in the layers of the harem are presented. As an alternative, the quality indicators of yarn obtained in the laboratory spinning device “Sherli” of small size from fiber were determined. As can be seen from the analysis of the test results, it was found that the comparative elongation strength of cotton obtained from the lower layer of the stack, the upper average length, elongation at break, the light output coefficient, decreased compared to other layers of the stack, on the contrary, the index of hip fibers, increased, decreased compared to other layers of the stack. In addition, according to the results of the tests obtained, the fiber viscosity index was obtained – the correlation between the properties of fibers and the properties of yarn, the thread viscosity index was estimated by the CSP (COUNT STRENGTH PRODUKT) coefficient, which was determined by the formula for carded yarn obtained in the laboratory spinning device “Sherli” from fiber stored in the refrigerator. The obtained results showed that the relationship between fiber properties and yarn properties due to the fact that the maturity index of a thread is at the top of the stack compared to the middle and lower part of the stack.

The transverse and longitudinal elastic constants of pulp fibers in paper sheets

Cellulose fibers are a major industrial input, but due to their irregular shape and anisotropic material response, accurate material characterization is difficult. Single fiber tensile testing is the most popular way to estimate the material properties of individual fibers. However, such tests can only be performed along the axis of the fiber and are associated with problems of enforcing restraints. Alternative indirect approaches, such as micro-mechanical modeling, can help but yield results that are not fully decoupled from the model assumptions. Here, we compare these methods with nanoindentation as a method to extract elastic material constants of the individual fibers. We show that both the longitudinal and the transverse elastic modulus can be determined, additionally enabling the measurement of fiber properties in-situ inside a sheet of paper such that the entire industrial process history is captured. The obtained longitudinal modulus is comparable to traditional methods for larger indents but with a strongly increased scatter as the size of the indentation is decreased further.

The effect of varied types of steel fibers on the performance of self-compacting concrete modified with volcanic pumice powder

The aim of this work involves studying the impact of varied types of steel fibers (SF) on the performance of self-compacting concrete (SCC), containing volcanic pumice powder (VPP). In this study, five types of steel fiber, which had a hooked end with two lengths of (SF1) and (SF3), flat end of length (SF2), in addition to the pointed end of (SF4) and (SF5) by 1% of volume fraction, were used. In addition, hybrid steel fiber (a mixture of all the steel fiber types) by 0.2% of volume fraction of concrete volume was used. Moreover, VPP was utilized by 30% cement mass as a substitute material for producing SCC. The impact of steel fiber properties in the shape of SF on the fresh concrete properties as slump flow and segregation were investigated. In addition to their influence on the compressive strength, split tensile strength, flexural strength, toughness, porosity, water absorption, and bulk density were examined. The results showed that SF led to decreasing the SCC fresh properties. Utilizing SF, on the other hand, improved the SCC hardened properties, as well as the toughness indices.

Genotype-environment interaction and stability of fiber properties and growth traits in triploid hybrid clones of Populus tomentosa

Background Clones provide a sensitive method for evaluating genotypic stability and detecting genotype-environment (G × E) interactions because of non-additive genetic effects among clones and there being no genetic effect among ramets of an ortet. With this study, we aimed to confirm and expand earlier findings, estimate stability parameters, and provide accurate estimates of clonal repeatabilities and genetic gains for a triploid breeding program of P. tomentosa Carr. Results Six 5-year-old clonal trials established in Northern China were used to determine the clonal variation, clone × site interactions, and the stability parameters of fiber properties of wood and growth traits. 360 trees from ten hybrid clones were collected from six sites. The clonal and site effects had a highly significant effect (P < 0.001) for all studied traits. While the clone × site interactions had a highly significant effect (P < 0.001) on fiber length (FL), coarseness (C), and tree growth (tree height [H], diameter at breast height [DBH] and stem volume [SV]), and a moderate effect (P < 0.05) on fiber width (FW) and fiber length/width (FL/W). For FL and SV, most of the triploid hybrid clones had higher reaction norms to the improvement in growth conditions and higher phenotypic plasticity. The estimated clonal repeatability of FW (0.93) was slightly higher than for FL (0.89), FL/W (0.83), C (0.91), DBH (0.76), H (0.85), and SV (0.80). Three clonal testing sites were sufficient to estimate quantitative parameters of fiber properties, however, more clonal testing sites would help improve the accuracy of quantitative parameters of the growth traits. Conclusions Our results highlight that accurate estimation of quantitative parameters for growth traits in triploid hybrid clones of P. tomentosa requires more clonal testing sites than the fiber properties.

Breeding assessment of new promising cotton lines

Cotton breeding in Bulgaria is mainly aimed at improving the earliness, productivity and fiber quality of modern varieties. The creation of new genetic diversity is one of the basic prerequisites for the success of breeding programs. The aim of the study was to evaluate cotton lines obtained by intraspecific and remote hybridization combined with backcross technology, with a view to their most effective usage in selection. Twenty-three lines were included in competitive variety trials conducted during the 2014-2017 period. The averaged results showed that lines 550, 639, 641, obtained by remote hybridization, appeared to be very promising. These three lines were distinguished by the best combination of productivity, fiber length and fiber lint percentage, and by these three indicators they exceeded the standard variety Chirpan-539. A new cotton variety Aida (No. 457) was approved, which in seed cotton yield and fiber yield, and technological fiber properties surpassed the standard varieties Chirpan-539 for earliness and productivity and Avangard-264 for fiber quality. The candidate variety 535 continued the state variety testing. Two new candidate cotton varieties No. 550 and No. 553 were released. In the state variety testing the three candidate varieties confirmed their qualities. The obtained lines, distinguished by one trait or by a complex of qualities, enriched the gene pool of Bulgarian cotton.

Soil-Cement Mixtures Reinforced with Fibers: A Data-Driven Approach for Mechanical Properties Prediction

The reinforcement of stabilized soils with fibers arises as an interesting technique to overcome the two main limitations of the stabilized soils: the weak tensile/flexural strength and the higher brittleness of the behavior. These types of mixtures require extensive laboratory characterization since they entail the study of a great number of parameters, which consumes time and resources. Thus, this work presents an alternative approach to predict the unconfined compressive strength (UCS) and the tensile strength of soil-binder-water mixtures reinforced with short fibers, following a Machine Learning (ML) approach. Four ML algorithms (Artificial Neural Networks, Support Vector Machines, Random Forest and Multiple Regression) are explored for mechanical prediction of reinforced soil-binder-water mixtures with fibers. The proposed models are supported on representative databases with approximately 100 records for each type of test (UCS and splitting tensile strength tests) and on the consideration of sixteen properties of the composite material (soil, fibers and binder). The predictive models provide an accurate estimation (R2 higher than 0.95 for Artificial Neuronal Networks algorithm) of the compressive and the tensile strength of the soil-water-binder-fiber mixtures. Additionally, the results of the proposed models are in line with the main experimental findings, i.e., the great effect of the binder content in compressive and tensile strength, and the significant effect of the type and the fiber properties in the assessment of the tensile strength.

Characterization of the Physical - Mechanical Properties of Alpaca Fiber (Vicugna Pacos) at the Tunshi Experimental Station

The alpaca is one of the four South American camelids that mainly inhabit the inter-Andean zone of Ecuador. Alpaca fiber is characterized by being a natural, soft and resistant fiber, of which, the fleece is the most valued part. The objective of this research was to evaluate the quality parameters of alpaca fiber in terms of physical-mechanical properties. The research was carried out in the Tunishi Experimental Station, ESPOCH. A descriptive statistic of mean, minimum and maximum range, and separation of means per student was applied. The alpaca with characteristics of Huacaya breed was selected and the shearing was carried out manually to obtain the fleece. Later, the performance of the fleece was evaluated, which was 85.71%. Two categories of fiber were selected: fine and thick. Sixty samples were taken for analysis by stretched and unstretched fiber length. The measurements of unstretched fiber length in cm for the thin and thick fiber were 12.50 cm and 13.52 cm respectively, presenting significant differences (p≤0.05). The measurements of the stretched fiber length in cm were 17.29 cm for fine fiber and 17.27 cm for thick fiber, presenting no significant differences (p≥0.05). The resistance of thread and fabric for fine fiber was 590 N/cm2, and for thick fiber was 2835.5 N/cm2, presenting highly significant differences (p≤0.01). Regarding the percentage of yarn elongation, the values obtained were 19% for fine fiber and 12% for thick fiber, observing highly significant differences (p≤0.01). The thick fiber fabric had a better resistance (2.3 BAR) than the fine fiber fabric (1.7 BAR), with a time of 2.34 s and 1.88 s respectively. The classification of the fiber by its softness did not present significant differences. Finally, regarding the sensory classification, it was established as a soft fiber with 91%. Keywords: alpaca, fleece, fine fiber, thick fiber, fiber properties. Resumen La alpaca es uno de los cuatro camélidos sudamericanos que principalmente habitan en la zona interandina del Ecuador. La fibra de alpaca se caracteriza por ser una fibra natural, suave y resistente; de la cual, el vellón es la parte de la fibra del animal más valorada. El objetivo de esta investigación fue evaluar los parámetros de calidad de fibra de alpaca en cuanto a las propiedades físico - mecánicas. La investigación se la realizó en la Estación Experimental TUNSHI - ESPOCH. Se aplicó una estadística descriptiva de media, rango mínimo y máximo y separación de medias por t estudent. Se seleccionó a la alpaca con características de la raza Huacaya y se realizó la esquila por el método manual para la obtención del vellón. Posteriormente, se evaluó el rendimiento del vellón el cual fue de 85,71%, se seleccionaron dos categorías de fibra fina y gruesa. Sesenta muestras fueron tomadas para su análisis: longitud de mecha estirada y sin estirar. La media de longitud de fibra sin estirar en cm para la fina y gruesa fueron de 12,50 y 13,52 correspondientemente, presentando diferencias significativas (p≤0,05), La media de la longitud en cm de fibra estirada determinó que la fibra fina presentó una media de 17,29 y la fibra gruesa de 17,27 cm, sin presentar diferencias significativas (p≥0,05). La resistencia del hilo y tejido para la fibra fina fue de 590 N/cm2 y para la gruesa fue de 2835,5 N/cm2, presentando diferencias altamente significativas (p≤0,01). Finalmente, en cuanto al porcentaje de elongación de hilo, presentó un 19% para fibra fina y un 12% para gruesa, observándose también diferencias altamente significativas (p≤0,01). El tejido de la fibra gruesa tuvo mejor resistencia (2,3 BAR) que el de la fibra fina (1,7 BAR), con un tiempo de 2,34 s y 1,88 s respectivamente. La clasificación de la fibra por su suavidad, no presentó diferencias significativas. En cuanto a la clasificación sensorial se la ubico como una fibra suave con el 91%. Palabras clave: alpaca, vellón, fibra fina, fibra gruesa, propiedades de la fibra.