51 research outputs found

    Nanofiber Filaments Fabricated by a Liquid-Bath Electrospinning Method

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    In order to investigate the forming process of multi-needle liquid-bath electrospun nanofiber filaments, nanofiber filaments were prepared using the multi-needle liquid-bath electrospinning method in this chapter. The effect of auxiliary electrode on jet state, and bundling and drawing processes of nanofibers were studied. The results show that the forming process of nanofiber filaments was mainly influenced by electrostatic field interference, bundling process, and drawing process, including two processes: forming process of as-spun nanofiber filaments and post-drawing process. In the forming process of as-spun nanofiber filaments, when the auxiliary electrode was added, the electrostatic field interference between needles reduced, inducing the decrease of jet offsets and the enhancement of Taylor cone and jet stability, and nanofibers with skin-core structure were finally deposited on the bath in good condition. The bundling process of nanofiber filament was divided into three processes: wet process, wet-dry process, and dry process; the structure transformation of nanofiber filaments mainly occurred in the wet process. In the post-drawing process, the crystallinity and alignment degree of nanofibers increased, and nanofiber diameter decreased. The initial modulus and breaking stress of filaments increased while the breaking strain of filaments decreased. Finally, nanofiber filaments were produced with better structures and properties

    Dry Sand Erosion Damage Characteristic of Fibers Induced by Solid Particle Impact

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    Bag filters made of fibrous components are widely used for cleaning exhaust gas. Filter damage caused by dust collection results from the erosion of the filter during particle collision. We developed an experimental and evaluation method to investigate the erosion characteristics of fibers. Using the suggested kinetic energy of impact, we evaluated the erosion wear characteristics of fibers under different experimental conditions. The results demonstrated that fiber erosion wear depended on the kinetic energy of impact. The level of erosion wear changes based on the material characteristics (brittle or ductile) and on the impact angle of solid particles. In addition, erosion characteristics are greatly influenced by strength and elongation properties of materials.ArticleTEXTILE RESEARCH JOURNAL. 80(16):1675-1681 (2010)journal articl

    Knowledge-Based Open Performance Measurement System (KBO-PMS) for a Garment Product Development Process in Big Data Environment

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    Globally, customers are getting increasingly demanding in terms of personalization of products and are asking for shorter product development periods with more predictable product performance, especially in fashion industry. Current market pressures drive firms to adapt new design process in product development (PD) processes. Nevertheless, choosing the effective PD process is a challenging, complex decision. There is a critical need to develop a performance measurements system (PMS) for choosing appropriate product development (PD) processes in garment design to support product mangers to effectively respond to market. This paper presents a knowledge-based open performance measurement system (KBO-PMS) in big data environment, in order to support complex industrial decision-making for new product development. Its dynamic and flexible structure enables the whole system to be more adapted to knowledge sharing of product managers and processing of various time-varying data. The proposed KBO-PMS is composed of an interactive structure, capable of both integrating new KPIs from the open resource and tracking the evolution of the KBO-PMS components with time. The proposed KBO-PMS has been validated by realizing the performance evaluation of product development (PD) in fashion industry. It can be regarded as an application of open-resource based dynamic group decision-making in fashion big data environment

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Microstructure Transitions and Dry-Wet Spinnability of Silk Fibroin Protein from Waste Silk Quilt

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    With excellent biocompatibility and biodegradability, silk fibroin has been developed into many protein materials. For producing regenerated silk fibroin (RSF) fibers, the conformation transition of silk fibroin needs to be thoroughly studied during the spinning process. Since the many silk fabrics that are discarded comprise an increasing waste of resources and increase the pressure on the environment, in this paper, waste silk fiber was recycled in an attempt to prepare regenerated fibroin fiber by dry-wet spinning. Ethanol was the coagulation bath. The rheological properties of all the RSF solutions were investigated to acquire rheology curves and non-Newtonian indexes for spinnability analysis. Four stages of the spinning process were carried out to obtain RSF samples and study their conformation transitions, crystallization, and thermal properties by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction, and differential scanning calorimetry. Quantitative analysis of the FTIR results was performed to obtain specific data regarding the contents of the secondary structures. The results showed that higher concentration spinning solutions had better spinnability. As the spinning process progressed, random coils were gradually converted into β-sheets and crystallization increased. Among the different influencing factors, the ethanol coagulation bath played a leading role in the conformation transitions of silk fibroin

    Non-isothermal crystallization kinetics of poly (lactic acid)/graphene nanocomposites.

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    Poly(lactic acid) (PLA)/graphene nanocomposites were prepared by solution blending and the dispersibility of graphene in the PLA matrix was examined by transmission electron microscopy (TEM). The non-isothermal crystallization behaviors of pure PLA and PLA/graphene nanocomposites from the melt were investigated by differential scanning calorimetry (DSC). The results showed that the graphene could play a role as a heterogeneous nucleating agent during the non-isothermal crystallizing process of PLA, and accelerate the crystallization rate. The non-isothermal crystallizing data were analyzed with the Avrami, Ozawa and Mo et al. models and the crystallization parameters of the samples were obtained. It is demonstrated that the combination of the Avrami and Ozawa models developed by Mo et al. was successful in describing the non-isothermal crystallization process for pure PLA and its nanocomposite. According to the Kissinger equation, the activation energies were found to be -154.3 and -179.5 kJ/mol for pure PLA and PLA/0.1 wt % graphene nanocomposite, respectively. Furthermore, the spherulite growth behavior was investigated by polarized optical microscopy (POM) and the results also supported the DSC data

    The Effect of Polyaniline (PANI) Coating via Dielectric-Barrier Discharge (DBD) Plasma on Conductivity and Air Drag of Polyethylene Terephthalate (PET) Yarn

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    In this paper, a simple method to prepare PANI-coated conductive PET yarn is reported, which involves pre-applying aniline and HCl vapors on PET surface and subsequent dielectric-barrier discharge (DBD) plasma treatment of the coated yarn under atmospheric pressure. The volume resistivity of the optimal sample was about 1.8 × 105 times lower than that of the control. Moreover, with the increase of coating amount of PANI, the air drag of PET yarns improved gradually. The surface chemistry of the treated yarn was analyzed by Fourier transform-infrared (FT-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS), while the morphology was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). This study offers a new method to prepare conductive fabric via air-jet loom and is expected to increase the weaving efficiency of air-jet loom
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