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1.
Heliyon ; 10(5): e27467, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38495140

RESUMO

This research provides an in-depth assessment of two paper yarn variants, examining their structural, functional, and performance characteristics. These yarns demonstrated favorable properties, including suitable linear density, twist, typical cellulosic functional groups as confirmed by Infrared spectroscopy, minimal hairiness, moisture transfer, and creditable mechanical strength. These yarns have flat layered cross-sections and grooved longitudinal surfaces. In addition, a low hairiness index (1.3-1.33) further acknowledged their smooth surface. Their remarkable evenness (15.86% and 7.08%) supported their effective wicking properties. Despite average breaking strength (0.77 cN/dTex and 1.05 cN/dTex) and moderate elongation, these yarns exhibited exceptional water-washing resistance and retained over 89% breaking strength after 15 washes. This study ranks these paper yarns as highly suitable for durable clothing fabrics, providing promising sustainable alternatives in the textile industry.

2.
Materials (Basel) ; 15(8)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35454603

RESUMO

Generally, comprehensive documents are needed to provide the research community with relevant details of any research direction. This study conducted the first descriptive bibliometric analysis to examine the most influential journals, institutions, and countries in the field of artificial intelligence in textiles. Furthermore, bibliometric mapping analysis was also used to examine diverse research topics of artificial intelligence in textiles. VOSviewer was used to process 996 articles retrieved from Web of Science-Core Collection from 2007 to 2020. The results show that China and the United States have the largest number of publications, while Donghua University and Jiangnan University have the highest output. These three themes have also appeared in textile artificial intelligence publications and played a significant role in the textile structure, textile inspection, and textile clothing production. The authors believe that this research will unfold new research domains for researchers in computer science, electronics, material science, imaging science, and optics and will benefit academic and industrial circles.

3.
Materials (Basel) ; 14(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34443075

RESUMO

Understanding the performance and behavior of garment leathers provides valuable inputs for the design and production of leather garments. The drape is one of the important properties associated with garment fitness quality and appeal. This study aims to show how the independent variables flexural rigidity and thickness affect the dependent variable drapability. Nowadays, studies on the drape of garment leathers are scarce. In this work, the drape coefficient (DC) was measured for sheep garment leather, which influences the garment drapability, such as flexural rigidity in the range of 9.2 to 22 and thickness in the range of 0.64 to 0.96. The average DC was calculated in the range of 47.35 to 69.9% for the selected sheep leathers from four samples. The drapability of the garment leather was determined using the DC. Flexural rigidity and thickness have been shown to have a considerable influence on the DC, while they do bear a significant relationship to the DC. The results of this study can be used as an elementary tool for leather selection of appropriate materials for garments.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33256162

RESUMO

Contest between the international or national enterprises stimulates the formation of innovative or improved products or of well-organized processes. Nevertheless, reliance on carbon-based materials and energy emission sources has been highlighted as a primary problem of the 21st century. The current study examines the influence of carbon disclosure information (CDI), media reporting and financial influence on state-owned enterprises (SOEs) and non-state-owned enterprises (NSOEs) by using Shenzhen and Shanghai's heavy polluting listed industries' dataset from 2014 to 2019. By applying different data approaches, the estimated results demonstrate that the CDI level is significantly negative related to SOE compared to NSOE. The estimated results explain that media's positive reporting offsets the additional benefits to stakeholders. While media's negative reporting negatively influences a firm's competitive position, it mitigates the stock price and its social value. Our results suggest that external factors are encouraging for the financial values of stakeholders, along with those of enterprises.


Assuntos
Carbono , Conservação dos Recursos Naturais , Revelação , Fontes Geradoras de Energia , China
5.
Polymers (Basel) ; 12(11)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238571

RESUMO

In this paper we designed greener rubber nanocomposites exhibiting high crosslinking density, and excellent mechanical and thermal properties, with a potential application in technical fields including high-strength and heat-resistance products. Herein 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc) ionic liquid was combined with silane coupling agent to formulate the nanocomposites. The impact of [EMIM]OAc on silica dispersion in a nitrile rubber (NBR) matrix was investigated by a transmission electron microscope and scanning electron microscopy. The combined use of the ionic liquid and silane in an NBR/silica system facilitates the homogeneous dispersion of the silica volume fraction (φ) from 0.041 to 0.177 and enhances crosslinking density of the matrix up to three-fold in comparison with neat NBR, and also it is beneficial for solving the risks of alcohol emission and ignition during the rubber manufacturing. The introduction of ionic liquid greatly improves the mechanical strength (9.7 MPa) with respect to neat NBR vulcanizate, especially at high temperatures e.g., 100 °C. Furthermore, it impacts on rheological behaviors of the nanocomposites and tends to reduce energy dissipation for the vulcanizates under large amplitude dynamic shear deformation.

6.
Materials (Basel) ; 13(12)2020 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-32570860

RESUMO

In this work, the tensile, compressive, and flexural properties of three types of 3D woven composites were studied in three directions. To make an accurate comparison, three 3D woven composites are made to have the same fiber volume content by controlling the weaving parameters of 3D fabric. The results show that the 3D orthogonal woven composite (3DOWC) has better overall mechanical properties than those of the 3D shallow straight-joint woven composite (3DSSWC) and 3D shallow bend-joint woven composite (3DSBWC) in the warp direction, including tension, compression, and flexural strength. Interestingly their mechanical properties in the weft direction are about the same. In the through-thickness direction, however, the tensile and flexural strength of 3DOWC is about the same as 3DSBW, both higher than that of 3DSSWC. The compressive strength, on the other hand, is mainly dependent on the number of weft yarns in the through-thickness direction.

7.
Materials (Basel) ; 12(14)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295844

RESUMO

Composite industry has long been seeking practical solutions to boost laminate through-thickness strengths and interlaminar shear strengths (ILSS), so that composite primary structures, such as stiffeners, can bear higher complex loadings and be more delamination resistant. Three dimensional (3D) woven fabrics were normally employed to render higher transverse and shear strengths, but the difficulty and high expense in producing such fabrics make it a hard choice. Based on a novel idea that the warp yarns that interlock layers of the weft yarns might provide adequate fiber crimps that would allow the interlaminar shear or radial stresses to be transferred and borne by the fibers, rather than by the relatively weaker matrix resin, thus improving the transverse strengths, this work provided a two point five dimensional (2.5D) approach as a practical solution, and demonstrated the superior transverse performances of an economical 2.5D shallow-bend woven fabric (2.5DSBW) epoxy composites, over the conventional two dimensional (2D) laminates and the costly 3D counterpart composites. This approach also produced a potential candidate to fabricate high performance stiffeners, as shown by the test results of L-beams which are common structural components of any stiffeners. This study also discovered that an alternative structure, namely a 2.5D shallow-straight woven fabric (2.5DSSW), did not show any advantages over the two control structures, which were a 2D plain weave (2DPW) and a 3D orthogonal woven fabric (3DOW) made out of the same carbon fibers. Composites of these structures in this study were conveniently fabricated using a vacuum-assisted resin infusion process (VARI). The L-beams were tested using a custom-made test fixture. The strain distribution and failure mode analysis of these beams were conducted using Digital Image Correlation (DIC) and X-ray Computed Tomography Scanning (CT). The results demonstrated that the structures containing Z-yarns or having high yarn crimps or waviness, such as in cases of 3DOW and 2.5DSBW, respectively, were shown to withstand high loadings and to resist delamination, favorable for the applications of high-performance structural composites.

8.
Materials (Basel) ; 12(8)2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30991643

RESUMO

Recently, the demand for reinforced plastics from natural, sustainable, biodegradable, and environmentally friendly fibers has been rising worldwide. However, the main shortcoming of natural fibers reinforced plastics is the poor compatibility between reinforcing fibers and the matrix. Hence, it is necessary to form a strong attachment of the fibers to the matrix to obtain the optimum performance. In this work, chemical treatments (acid pretreatment, alkali pretreatment, and scouring) were employed on jute fibers to modify them. The mechanical properties, surface morphology, and Fourier transform infrared spectra of treated and untreated jute fibers were analyzed to understand the influence of chemical modifications on the fiber. Then, jute fiber/epoxy composites with a unidirectional jute fiber organization were prepared. Basic properties of the composites such as the void fraction, tensile strength, initial modulus, and elongation at break were studied. The better interfacial adhesion of treated fibers was shown by scanning electron microscope (SEM) images of fractured coupons. Hence, the chemical treatment of jute fiber has a significant impact on the formation of voids in the composites as well as the mechanical properties of jute fiber composites.

9.
Materials (Basel) ; 12(5)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866408

RESUMO

Due to the non-polar nature and low wettability of carbon fibers (CFs), the interfacial adhesion between CFs and the polyetheretherketone (PEEK) matrix is poor, and this has negative effects on the mechanical properties of CF/PEEK composites. In this work, we established a modification method to improve the interface between CFs and PEEK based chemical grafting of aminated polyetheretherketone (PEEK-NH2) on CFs to create an interfacial layer which has competency with the PEEK matrix. The changed chemical composition, surface morphology, surface energy, and interlaminar shear strength were investigated. After grafting, the interlaminar shear strength (ILSS) was improved by 33.4% due to the covalent bonds in the interface region, as well as having good compatibility between the interface modifier and PEEK. Finally, Dynamic Mechanical Analysis (DMA) and Scanning Electron Microscopy (SEM) observation also confirmed that the properties of the modified CF/PEEK composites interface were enhanced. This work is, therefore, a beneficial approach towards enhancing the mechanical properties of thermoplastic composites by controlling the interface between CFs and the PEEK matrix.

10.
Molecules ; 23(3)2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29494527

RESUMO

Thermoplastic towpregs are convenient and scalable raw materials for the fabrication of continuous fiber-reinforced thermoplastic matrix composites. In this paper, the potential to employ epoxy and styrene-acrylic sizing agents was evaluated for the making of carbon fiber thermoplastic towpregs via a powder-coating method. The protective effects and thermal stability of these sizing agents were investigated by single fiber tensile test and differential scanning calorimetry (DSC) measurement. The results indicate that the epoxy sizing agent provides better protection to carbon fibers, but it cannot be used for thermoplastic towpreg processing due to its poor chemical stability at high temperature. The bending rigidity of the tows and towpregs with two styrene-acrylic sizing agents was measured by cantilever and Kawabata methods. The styrene-acrylic sized towpregs show low torque values, and are suitable for further processing, such as weaving, preforming, and winding. Finally, composite panels were fabricated directly from the towpregs by hot compression molding. Both of the composite panels show superior flexural strength (>400 MPa), flexural modulus (>63 GPa), and interlaminar shear strength (>27 MPa), indicating the applicability of these two styrene-acrylic sizing agents for carbon fiber thermoplastic towpregs.


Assuntos
Carbono/química , Fenômenos Mecânicos , Polímeros/química , Estireno/química , Fibra de Carbono , Teste de Materiais , Propriedades de Superfície , Temperatura
11.
Polymers (Basel) ; 10(10)2018 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-30961060

RESUMO

Optimization of the mechanical and thermal properties of isotactic polypropylene (iPP) homopolymer blended with relatively new low molecular low modulus polypropylene (LMPP) at different blend ratios was carried out via surface response methodology (RSM). Regression equations for the prediction of optimal conditions were achieved considering eight individual parameters: naming, elongation at break, tensile strength and elastic modulus, crystallization temperature (TC), first melting temperatures (TM1), heat fusion (Hf), crystallinity, and melt flow rate (MFR), which were measured as responses for the design of experiment (DOE). The adjusted and predicted correlation coefficient (R²) shows good agreement between the actual and the predicted values. To confirm the optimal values from the response model, supplementary experiments as a performance evaluation were conducted, posing better operational conditions. It has been confirmed that the RSM model was adequate to reflect the predicted optimization. The results suggest that the addition of LMPP into iPP could effectively enhance the functionality and processability of blend fibres if correctly proportioned.

12.
Appl Opt ; 56(12): 3570-3576, 2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-28430236

RESUMO

Synthetic fibers account for about half of all fiber usage, with applications in every textile field. The phenomenon of fiber composition not matching the label harms consumer interests and impedes market development. Hyperspectral imaging technology as a potential technique can be utilized to discriminate mass synthetic fibers rapidly and nondestructively and achieves the functions that traditional Fourier transform infrared instruments do not have. On the basis of investigating the impact of dope-dyeing and wrapping processes on spectra, the spectral features (from 900 to 2500 nm) of six categories of synthetic fibers were extracted with a hyperspectral imaging system. A principal component analysis-linear discriminant analysis model was developed to discriminate the chemical content of fibers in different colors and structures, which showed 100% discrimination accuracy. Results demonstrated the feasibility of a hyperspectral imaging system in synthetic fiber discrimination. Therefore, this method offers a more convenient alternative for textile industry on-site discrimination.

13.
Pak J Med Sci ; 29(5): 1167-72, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24353713

RESUMO

OBJECTIVES: To assess the validity /strength of clinical diagnosis of Malaria on the basis of IMNCI algorithm by slide microscopy (gold standard) and to compare the effectiveness of Rapid Diagnostic Test (RDT )against slide microscopy. Methods : It is a descriptive cross sectional study of 6 month duration conducted at Pediatric Outpatient Department LUH Hyderabad from June-Dec. 2010. Sample of 400{the minimum required sample was 385 with malaria prevalence 5% (0.05) with margin of error of 3% (0.03, frequency vary from 2-8 % among different studies)} febrile children under 5 years classified as Suspected Clinical Malaria according to algorithm of IMNCI were included; The operational definition for Suspected Clinical Malaria was; fever for more than 2 days with no runny nose, no measel rash and no other cause of fever. Hyderabad was considered as low risk area. Rapid diagnostic test (RDT) and slide microscopy were done, and only confirmed cases were treated according to current guidelines given by National Malaria Program/updated IMNCI. RESULTS: Total 2000 patients under 5 years presented with fever and were evaluated. From 2000 cases 20% (400) were diagnosed as suspected clinical Malaria according to IMNCI algorithm; and only 40 cases (10%) have shown positive results for malaria parasite on slide microscopy and 38 cases on RDT. Regarding the plasmodium species 70% were vivax and 30% were falciparum. As regards the effectiveness, RDT has shown 95% sensitivity for the detection of plasmodium antigens in the febrile clinically suspected cases of malaria. CONCLUSION: Prompt and accurate diagnosis of malaria is needed for implementation of appropriate treatment to reduce unnecessary anti-malarial prescription. RDT is as effective as slide microscopy for the diagnosis of malaria especially in resource poor countries.

14.
Malar J ; 11: 144, 2012 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-22551061

RESUMO

BACKGROUND: Infection by Plasmodium vivax has been considered rarely threatening to life, but recent studies challenge this notion. This study documented the frequency and character of severe illness in paediatric patients admitted to a hospital in south-eastern Pakistan with a laboratory-confirmed diagnosis of vivax malaria. METHODS: An observational study of all 180 paediatric patients admitted with any diagnosis of malaria during 2010 was conducted: 128 P. vivax; 48 Plasmodium falciparum; and four mixed infections of these species. Patients were classified as having severe illness with any of the following indicators: Glascow coma scale <11; ≥2 convulsions; haemoglobin <5g/dL; thrombocytes <50,000/mL; blood glucose <45mg%; >70 breaths/min; or intravenous anti-malarial therapy. Additionally, 64 patients with a diagnosis of vivax malaria were treated during 2009, and the 21 of these having severe illness were included in analyses of the frequency and character of severe illness with that diagnosis. RESULTS: During 2010, 39 (31%) or 37 (77%) patients with a diagnosis of P. vivax or P. falciparum were classified as having severe disease. Including the 2009 records of 64 patients having vivax malaria, a total of 60 (31%) patients with severe illness and a diagnosis of P. vivax were available. Altered mental status (Glascow coma scale score <11; or ≥2 convulsions) dominated at 54% of the 83 indicators of severe illness manifest among the patients with vivax malaria, as was true among the 37 children with a diagnosis of falciparum malaria and being severely ill; 58% of the 72 indicators of severe disease documented among them. No statistically significant difference appeared in frequencies of any other severe disease indicators between patients diagnosed with vivax or falciparum malaria. Despite such similarities, a diagnosis of falciparum malaria nonetheless came with 3.8-fold (95% CI = 1.8-8.1) higher risk of presenting with severe illness, and 8.0-fold (95% CI = 2.1-31) greater likelihood of presenting with three or more severe disease indicators. Two patients did not survive hospitalization, one each with a diagnosis of falciparum or vivax malaria. CONCLUSIONS: Vivax malaria caused a substantial burden of potentially life-threatening morbidity on a paediatric ward in a hospital in south-eastern Pakistan.


Assuntos
Hospitalização , Malária Vivax/epidemiologia , Malária Vivax/patologia , Plasmodium vivax/isolamento & purificação , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Prevalência , Índice de Gravidade de Doença
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