204 research outputs found

    Effect of Dielectric Barrier Discharge Parameters on Certain Properties of Natural Polymeric Material (Cotton) Fiber

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    Dielectric Barrier Discharge (DBD) plasma reactor, operated at atmospheric pressure was used for modifying the properties of bleached plain woven cotton fabrics. Cotton fabric was treated at 3.0, 3.5 and 4.0 kV electrode current for 2.5, 5.0, and 7.5 min in the presence of air plasma, in order to establish the chemical effect on cotton fiber. Some properties such as wick-ability, absorbency, tensile strength, tear strength, dye-ability; FT-IR analysis and surface morphology analysis were carried-out as well. The outcomes revealed that, plasma treatment resulted in surface etching, generation of carboxylic and carbonyl group contents in cotton fiber. The increased carbonyl and carboxylic group content resulted in enhancement of fiber wettability and rate of fabric vertical wicking. The reactive dyes uptake of treated samples were increased almost linearly but decreased with increased treatment time and intensity of voltage across the electrodes. A slight increase in tensile and tear strength was found in air plasma treated fabrics. Yellowness of the fabric was increased after plasma treatment. The SEM micrographs confirmed the atmospheric plasma could modify the fiber surface outwardly

    Effect of dielectric barrier discharge parameters on properties of mulberry silk fibre

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    A dielectric barrier discharge reactor operated at atmospheric pressure has been used to modify the properties of plain woven silk fabrics. Operating parameters, such as treatment time, and the intensity of current across the electrodes has been changed in the presence of air as a plasma gas. Properties such as wickability, absorbency, tensile strength, tear strength, dyeability measurements; Fourier transform infrared spectroscopy FTIR analysis; and surface topology investigations have been carried out in this study. The findings reveal that the plasma treatment results in surface etching and generation of new functional groups mainly oxygen and oxygen-containing groups. Newly formed functional groups contribute to the improvement in water absorbency and the rate of vertical wicking on silk stripe. Selected acid and basic dye uptakes on treated samples are found to increase almost linearly, but the values decrease with the increase in treatment duration at a higher discharge current. A slight increase in tensile and tear strength is observed in air plasma treated silk fabrics. Air plasma treatment of silk fabric in high energy barrier discharge results in an increase in yellowness. SEM micrographs clearly confirm the formation of ripple like surface morphology in the form of micro-roughness created by etching effect of active species of air plasma

    Monocular 3D Object Detection with Decoupled Structured Polygon Estimation and Height-Guided Depth Estimation

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    Monocular 3D object detection task aims to predict the 3D bounding boxes of objects based on monocular RGB images. Since the location recovery in 3D space is quite difficult on account of absence of depth information, this paper proposes a novel unified framework which decomposes the detection problem into a structured polygon prediction task and a depth recovery task. Different from the widely studied 2D bounding boxes, the proposed novel structured polygon in the 2D image consists of several projected surfaces of the target object. Compared to the widely-used 3D bounding box proposals, it is shown to be a better representation for 3D detection. In order to inversely project the predicted 2D structured polygon to a cuboid in the 3D physical world, the following depth recovery task uses the object height prior to complete the inverse projection transformation with the given camera projection matrix. Moreover, a fine-grained 3D box refinement scheme is proposed to further rectify the 3D detection results. Experiments are conducted on the challenging KITTI benchmark, in which our method achieves state-of-the-art detection accuracy.Comment: 11 pages, 8 figures, AAAI202

    Electrolyte influence on sorption behaviours of Direct Blue 71 dye on ramie fibre

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    Ramie loose fibre was dyed using Direct Blue 71 dye at 70, 80, 90 and 100°C without and with NaCl electrolyte in order to investigate the distinction of dye sorption behaviours. The results show that the dye exhaustion increases with addition of NaCl and shortens the equilibrium dyeing time. The dye adsorption process of dyeing without and with NaCl followed pseudo second-order kinetics, but the rate constant of sorption is larger for the latter compared to the former

    Characterize the assembly of dark matter halos with protohalo size histories: I. Redshift evolution, relation to descendant halos, and halo assembly bias

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    We propose a novel method to quantify the assembly histories of dark matter halos with the redshift evolution of the mass-weighted spatial variance of their progenitor halos, i.e. the protohalo size history. We find that the protohalo size history for each individual halo at z~0 can be described by a double power-law function. The amplitude of the fitting function strongly correlates to the central-to-total stellar mass ratios of descendant halos. The variation of the amplitude of the protohalo size history can induce a strong halo assembly bias effect for massive halos. This effect is detectable in observation using the central-to-total stellar mass ratio as a proxy of the protohalo size. The correlation to the descendant central-to-total stellar mass ratio and the halo assembly bias effect seen in the protohalo size are much stronger than that seen in the commonly adopted half-mass formation time derived from the mass accretion history. This indicates that the information loss caused by the compression of halo merger trees to mass accretion histories can be captured by the protohalo size history. Protohalo size thus provides a useful quantity to connect protoclusters across cosmic time and to link protoclusters with their descendant clusters in observations.Comment: 19 pages, 12 + 8 figures, comments are welcome

    Generation of tooth profile for roots rotor based on virtual linkage associated with Assur group

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    This article, for the first time, presents the generation of Roots rotor tooth profiles based on an Assur-group-associated virtual linkage method. Taking the original Roots rotor as an example, structure and geometry of the Roots rotor are introduced, and based on the principle of inversion, an equivalent virtual linkage is identified for generating dedendum tooth profile of the rotor. Using linkage decomposition associated with elemental Assur groups, algorithm for computing the tooth curve is constructed leading to the explicit expression of rotor profile and the corresponding numerical simulation, verifying the validity of the proposed approach. For demonstration purpose, the virtual linkage method is then extended to the generation of tooth profiles for the variants of Roots rotors with arc-cycloidal curves and arc-involute curves. Integrated with computer-aided design, computer-aided engineering and computer-aided manufacturing software platforms, as well as the three-dimensional printing technology, this article provides an efficient and intuitive approach for Roots rotor system design, analysis and development

    Effluent-free deep dyeing of cotton fabric with cacao husk extracts using the Taguchi optimization method

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    Textile dyehouses are under scrutiny because they discharge colored and hazardous effluents to waterways. There is a need to develop an alternative dyeing system that does not produce any hazardous effluent. The waterless dyeing method could be a viable eco-friendly alternative to the traditional aqueous dyeing method. In this work, cacao husk extracts were used as a natural dye in the decamethylcyclopentasiloxane (D5) medium for the dyeing of cotton fabric, and subsequently, the dyed cotton was treated by a fixation treatment with a cationic dye-fixing agent in the D5 medium. The cotton fabric dyed with cacao husk extracts exhaustion in the waterless D5 medium exhibited better exhaustion, fixation rate, color strength (K/S), and colorfastness to washing and rubbing compared to the fabric dyed with the same extracts using the conventional aqueous dyeing and dye-fixing methods. The dye exhaustion percentage and the dye fixation rate were 95.6% and 94.8% in the D5 medium respectively, which is significantly higher in comparison to a 48.2% dye exhaustion percentage and a 35.3% dye fixation rate in the conventional water medium. An orthogonal array design (L9) was adopted to optimize the dyeing conditions with respect to exhaustion percentage. The results indicated that the dyebath temperature was the most important factor for achieving the optimal dye exhaustion, and dyeing time also showed considerable effects. Linear regression was used to predict the exhaustion percentage, and the resulting p value of 0.000 demonstrated that a strong coefficient was proven among all selected factors. This study has demonstrated that dyeing of cotton fabric with cacao husk extracts in the D5 dyeing system can be a viable method for the textile industry with minimal environmental pollution

    Long-term postoperative quality of life in childhood survivors with cerebellar mutism syndrome

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    BackgroundTo investigate the long-term quality of life (QoL) of children with cerebellar mutism syndrome (CMS) and explore the risk factors for a low QoL.ProcedureThis cross-sectional study investigated children who underwent posterior fossa surgery using an online Pediatric Quality of Life Inventory questionnaire. CMS and non-CMS patients were included to identify QoL predictors.ResultsSixty-nine patients were included (male, 62.3%), 22 of whom had CMS. The mean follow-up time was 45.2 months. Children with CMS had a significantly lower mean QoL score (65.3 vs. 83.7, p < 0.001) and subdomain mean scores (physical; 57.8 vs. 85.3, p < 0.001; social: 69.5 vs. 85.1, p = 0.001; academic: p = 0.001) than those without CMS, except for the emotional domain (78.0 vs. 83.7, p = 0.062). Multivariable analysis revealed that CMS (coefficient = −14.748.61, p = 0.043), chemotherapy (coefficient = −7.629.82, p = 0.013), ventriculoperitoneal (VP) shunt placement (coefficient = −10.14, p = 0.024), and older age at surgery (coefficient = −1.1830, p = 0.007) were independent predictors of low total QoL scores. Physical scores were independently associated with CMS (coefficient = −27.4815.31, p = 0.005), VP shunt placement (coefficient = −12.86, p = 0.025), and radiotherapy (coefficient = −13.62, p = 0.007). Emotional score was negatively associated with age at surgery (coefficient = −1.92, p = 0.0337) and chemotherapy (coefficient = −9.11, p = 0.003). Social scores were negatively associated with male sex (coefficient = −13.68, p = 0.001) and VP shunt placement (coefficient = −1.36, p = 0.005), whereas academic scores were negatively correlated with chemotherapy (coefficient = −17.45, p < 0.001) and age at surgery (coefficient = −1.92, p = 0.002). Extent of resection (coefficient = 13.16, p = 0.021) was a good predictor of higher academic scores.ConclusionCMS results in long-term neurological and neuropsychological deficits, negatively affecting QoL, and warranting early rehabilitation

    Broadening Color Shade of Dyed Wool Fibre with Binary and Ternary Natural Plant Dye Combinations

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    A limited selection of natural dyes’ color impedes the development of textile dyeing with natural plant dyes. Inspiring by the conventional coloration of textiles with a combination of three synthetic dyes generally, the present work is to investigate the broadening color shade of dyed wool fiber with ternary natural dye combinations of madder red (MR), gardenia yellow (GY), and gardenia blue (GB) without mordants in a decamethylcyclopentasiloxane (D5) medium. The wool yarn was wetted in an aqueous solution of pH 3 to own a 300% pickup rate, followed by immersion in a D5 medium containing 2% of alcohol ethoxylate (AEO-3) and solid natural dyes at 90°C for 90 min for coloration. The colorfastness to washing was achieved at a 4–5 for fading and a 5 rating for staining for all colors. The XRD patterns and TGA analysis confirmed that the dyeing procedure did not affect the crystallinity nature and stable thermal tendency. SEM images and cross-sections showed that the dyeing procedure did not damage the morphological structure of the wool fiber surface, and the dyes were evenly distributed. Finally, many color shades of dyed fibers were prepared with various dyes’ ratios
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