The mesoscale packing and crystal structure of cellulose microfibrils as well as temporal changes in cell wall composition and hydration during the development of cotton fibers from two species, ...Gossypium hirsutum and G. barbadense were studied using vibrational sum frequency generation (SFG), attenuated total refection infrared (ATR-IR), Fourier transform Raman (FT-Raman) spectroscopy and X-ray diffraction (XRD). The developmental stages analyzed (13–60 days post anthesis) included primary wall synthesis, transitional cell wall remodeling, secondary wall thickening via synthesis of nearly pure cellulose, and fiber maturation. ATR-IR and FT-Raman combined with principle component analysis revealed that fibers of both species undergo abrupt changes in the cellulose and matrix polymer contents during the transition to secondary cell wall synthesis. XRD revealed that cellulose crystal size and crystallinity increase similarly over time in both species. SFG analysis of fibers from un-opened bolls, which were stored in water then air dried, showed subtle differences between two species in the mesoscale ordering of cellulose microfibrils in the maturing secondary walls. In the samples of mature fibers dried on the plant after the boll split opened naturally, the difference in SFG spectra between species was negligible. Collectively, the results show that (a) SFG can uniquely reveal differences in cellulose fibril ordering in maturing cotton fibers before boll opening; and (b) illustrate the comparative usefulness of other commonly used spectroscopic analytical methods for cotton fiber analysis.
Naturally colored cotton is a green textile material. To cultivate new colored cotton and improve its performance, we must first understand the types, composition, and formation mechanism of the ...pigments in colored cotton. This study aims to explore the composition and structure of cotton fiber pigments. Qualitative analyses of pigment extracts from brown cotton, green cotton, and white cotton fibers were carried out using ultraviolet spectroscopy, diagnostic agents, and liquid chromatography–mass spectrometry. The main component of cotton fiber pigments was flavonoids, and specific types of flavonoids were found in the pigments in brown cotton, green cotton, and white cotton fibers. Research on the composition of cotton fiber pigments can increase our understanding of colored cotton fibers and lay a foundation for the cultivation, planting, and development of colored cotton fibers, as well the identification of naturally colored cotton from dyed cotton.
Dynamic remodeling of the actin cytoskeleton plays a central role in the elongation of cotton fibers, which are the most important natural fibers in the global textile industry. Here, a ...high-resolution mapping approach combined with comparative sequencing and a transgenic method revealed that a G65V substitution in the cotton actin Gh_D04G0865 (GhACT17D in the wild-type) is responsible for the
Ligon lintless-1 (
) mutant (GhACT17DM). In the mutant GhACT17DM from
plant, Gly65 is substituted with valine on the lip of the nucleotide-binding domain of GhACT17D, which probably affects the polymerization of F-actin. Over-expression of
, but not
, driven by either a CaMV35 promoter or a fiber-specific promoter in cotton produced a
-like phenotype. Compared with the wild-type control, actin filaments in
fibers showed higher growth and shrinkage rates, decreased filament skewness and parallelness, and increased filament density. Taken together, our results indicate that the incorporation of GhACT17DM during actin polymerization disrupts the establishment and dynamics of the actin cytoskeleton, resulting in defective fiber elongation and the overall dwarf and twisted phenotype of the
mutant.
Electrostatic self-assembly layer by layer technique was used to immobilize ZnO/SiO
2
nanocompsite on cationized cotton fabric. This occurs via the sequential dipping of cotton fabric in dilute ...solutions of poly (diallyldimethylammonium chloride) (PDDA) and ZnO/SiO
2
colloidal suspension nanocomposite of different concentration ratios 1:0, 0:1, 1:1, 2:1, 1:2, and 2:2. The formation of multilayer thin film on cotton fabric creates different functional properties. UV protection properties were monitored at the ratio of (Zn/Si) as well as the number of layers. In the case of 1(Bilayer)BL and 5(Bilayer)BL, increasing the ratio of (ZnO/SiO
2
) within the nano composite (ZnO/SiO
2
) ratio, the UPF increases and the results indicate that the best ultraviolet protection factor is obtained when the Zn/Si ratio is 2. Additionally, dyeing the treated fabric often enhanced protection against ultra violet rays. FTIR spectra were utilized to distinguish the existence of effective groups on the surface of the treated cotton. Scanning electron microscopy studies confirmed successful deposition of the PDDA/(ZnO/SiO
2
) nanocomposite. Moreover, cotton fibers connected together because of the increased coating density and their surface become rougher. Post treatment by stearic acid rendered the fabric water repellent property. Other physical properties such as tensile strength as well as breathability of the cotton fabric were investigated.
Medical textiles are one of the most rapidly growing parts of the technical textiles sector in the textile industry. This work aims to investigate the medical applications of a curcumin/TiO2 ...nanocomposite fabricated on the surface of cotton fabric. The cotton fabric was pretreated with three crosslinking agents, namely citric acid, 3-Chloro-2-hydroxypropyl trimethyl ammonium chloride (Quat 188) and 3-glycidyloxypropyltrimethoxysilane (GPTMS), by applying the nanocomposite to the modified cotton fabric using the pad-dry-cure method. The chemistry and morphology of the modified fabrics were examined by Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and scanning electron microscopy. In addition, the chemical mechanism for the nanocomposite-modified fabric was reported. UV protection (UPF) and antibacterial properties against Gram-positive S. aureus and Gram-negative E. coli bacterial strains were investigated. The durability of the fabrics to 20 washing cycles was also examined. Results demonstrated that the nanocomposite-modified cotton fabric exhibited superior antibacterial activity against Gram-negative bacteria than Gram-positive bacteria and excellent UV protection properties. Moreover, a good durability was obtained, which was possibly due to the effect of the crosslinker used. Among the three pre-modifications of the cotton fabric, Quat 188 modified fabric revealed the highest antibacterial activity compared with citric acid or GPTMS modified fabrics. This outcome suggested that the curcumin/TiO2 nanocomposite Quat 188-modified cotton fabric could be used as a biomedical textile due to its antibacterial properties.
Cotton fabrics were dyed with the madder and compounds of citric acid (CA) and dicarboxylic acids tartaric acid (TTA), malic acid (MLA), succinic acid (SUA) as cross-linking agents and sodium ...hypophosphite (SHP) as the catalyst. The molecular structures and crystal structures of the dyed cotton fabrics were analyzed using Fourier-transform infrared spectroscopy (FTIR) and X-ray diffractometry (XRD), respectively. The results showed that the polycarboxylic acids esterified with the hydroxyl groups in the dye and cellulose, respectively, and the reaction mainly occurred in the amorphous region of the cotton fabric. Compared with the direct dyed cotton fabric, the surface color depth (K/S) values of the CA, CA+TTA, CA+MLA, CA+SUA cross-linked dyed cotton fabrics increased by approximately 160%, 190%, 240%, 270%, respectively. The CA+SUA cross-linked dyed cotton fabric achieved the biggest K/S value due to the elimination of the negative effect by α-hydroxyl in TTA and MLA on esterification reaction, and the cross-linked dyed cotton fabrics had great levelness property. The washing and rubbing fastness of the cross-linked cotton fabrics were above four levels. The light resistance stability and the antibacterial property of the cross-linked dyed cotton fabrics was obviously improved. The sum of warp and weft wrinkle recovery angle (WRA) of the CA+SUA cross-linked dyed cotton fabric was 55° higher than that of raw cotton fabric, and its average UV transmittance for UVA was less than 5% and its UPF value was 50+, showing a great anti-wrinkle and anti-ultraviolet properties.
Low phosphorus (P) availability is a major constraint for cotton production. Consequently, P-efficient genotypes can improve productivity under conditions where the higher application of P is not ...economical. This study was conducted to characterize cotton genotypes for P-use efficiency under various P concentrations (0, 10, 20, 40, 80, and 500 μM KH2PO4). The results showed large genotypic variation in five selected traits, such as root dry weight, shoot dry weight, photosynthetic activity, P-utilization efficiency, and P-uptake efficiency. Based on these five selected traits, the genotypes were grouped into three main classes as efficient, moderate efficient, and inefficient genotypes as proposed by different researchers. Most of the genotypes behaved in a similar pattern under different P concentrations. Among the genotypes, Xinluzao-49 and Xinluzao-48 were considered as P efficient while CCRI-64 and Yumian-21 as inefficient genotypes. However, the rest of the genotypes were considered as moderately P efficient. The results prove that a large genetic potential exists in cotton genotypes for P-use efficiency, and the use of P-efficient genotypes for cultivation will reduce the application of phosphatic fertilizers. Furthermore, the use of P-efficient genotypes will improve cotton breeding activities and help in improving the environmental sustainability of cotton production.
Abstract
This article is devoted to the issue of increasing the efficiency of vertical-spindle cotton pickers by rational choice of kinematic and geometrical parameters of the main working body – the ...spindle drum. In particular, in the work, an analysis of the actual operating conditions of the spindles, existing machines, and the results of previous studies in this area indicate the main reasons for the low efficiency of cotton pickers. As a criterion for evaluating the efficiency of the vertical spindles, the “activity” of the spindles and the force that occurs between the cotton boll and the surface of the latter are taken. It is shown that the design features of the existing vertical spindle drums do not allow increasing the active surface of the spindles and their favorable orientation relative to cotton bolls in the collection area. It is substantiated that in order to increase the activity of the spindles in the collection zone, it is necessary to inform them, as they move in this zone, of the variable speed and trajectory of the spindle movement, which improves the conditions for the interaction of the latter with the cotton boll. The obtained results are compared and analyzed with the same results of the existing spindle drums, which showed a significant increase in the activity of the spindles when using elliptical drums as the main working body of the cotton picker.
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