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Experimental data on the effect of the ambient atmosphere (a vacuum or argon) on the phase composition of silicon carbide fibers formed upon the siliconization of carbon felt are presented. The major phases produced in the siliconization of carbon felt are β-SiC (3C) in vacuo and α-SiC (6H) in the argon atmosphere. When carbon felt is siliconized in vacuo, residual silicon is present on the surface of the silicon carbide felt fibers. The ambient atmosphere determines the nature of the siliconization process at 1650°C: in vacuo, SiC is formed due to the reaction of carbon fibers with the silicon melt wetting them, while in argon, it is formed due mainly to the reaction with vaporous silicon. [ABSTRACT FROM AUTHOR]

Due to the development of modern wearable mobile devices, the need of antenna with smaller size and internally flexible to fit becomes necessary. Miniaturization of Micro Strip Patch (MSP) antenna increases its employability for communication in different aspects. The use of flexible material for the fabrication of MSP antenna still improves its use for Wireless Body Area Networks (WBAN) which includes devices for monitoring systems in military, surveillance and medical applications. The devices designed specifically in Industrial Scientific Medical (ISM) band are used for communication in these applications. Defected Ground Structure (DGS) is adopted as an emerging technique for improving the various parameters of microwave circuits, that is, narrow bandwidth, cross-polarization, low gain, and so forth. In this paper, the design of compact micro strip patch antenna using different flexible substrate materials with DGS is proposed to resonate the antenna at 2.45GHz ISM band which can be used as biomedical sensors. Felt and Teflon with dielectric constant 1.36 and 2.1respectively are chosen as flexible substrate material among various flexible materials like cotton, rubber, paper, jeans etc. Using CST studio suite software, the designed antenna is simulated and the fabricated antenna is tested with Vector Network Analyzer (VNA). The performance parameters like return loss, gain, directivity and Voltage Standing Wave Ratio (VSWR) of the antenna are analyzed. [ABSTRACT FROM AUTHOR]

In this paper, I invoke various matterings of felt in order to generate a practice of writing that engenders bodily difference that is affective, moving, and wooly. In attending to 'how to write as felt,' as a touching encounter, I consider how human and nonhuman matter composes (Haraway in Staying with the trouble: making Kin in the Chthulucene, Duke University Press, Durham, 2016). This co-mingling that felt performs enacts what Alaimo (Bodily natures: science, environment, and the material self, Indiana University Press, Bloomington, 2010; Exposed: Environmental politics and pleasures in posthuman times, University of Minnesota Press, Minneapolis, 2016) calls transcorporeality. Connecting felt with theories of touch and transcorporeality becomes a way to open up and re-configure different bodily imaginaries, both human and nonhuman, that are radically immanent and intensive; as an assemblage of forces and flows that open bodies to helices and trans connections (Springgay and Truman in Body Soc 23(4):27-58, 2017b). My contribution to this collection on 'humanity in a posthuman age' is experimental and performative. Felt is activated not as a metaphor but rather poses questions about what writing does at the interstices between research and creation. [ABSTRACT FROM AUTHOR]

Fiber reinforced composite fabrics have become very ambitious engineering structures in recent years and have successfully replaced current metallic and other materials in many important sectors of industry especially in automotive. The applications of composite materials are being increased nowadays and this will increase future because of low cost manufacturing, suitable for mass production In order to increase the market penetration and because of current stringent legistation to increase safety, improvements in flame retardancy have been given significant priority especially in automotive industry. In this study, recycled e-glass/cotton reinforced with epoxy resin composite felt is produced with different fabric mass per unit area. The main purpose of the investigation illustrated in this study has been evaluated flammability behaviour. Flame retardant is applied with different volume ratio (1, 3, 5 %) for determining the flammability of textile fabrics. These results show that percentage of natural fibers has positive effect on improving flammability behavior of fabrics. [ABSTRACT FROM AUTHOR]

In this review article, we describe several topics, including the sandwich technique, the transatrial re-endocardialization technique, the limited apical left ventriculotomy approach and device closure. The sandwich technique was introduced for the closure of muscular ventricular septal defects (VSD) by sandwiching the septum between two felt patches placed in the left and right ventricle. This technique requires neither the transection of muscular trabeculae nor ventriculotomy. Although the sandwich technique has resulted in the improvement of surgical outcomes, cases of postoperative cardiac dysfunction have been reported. Multiple smaller VSDs have been closed with transatrial re-endocardialization. Septal dysfunction may be avoided through this technique, in which the septal trabeculae are approximated in two layers of superficial, endocardial running sutures. Recently, a number of reports have recommended a limited apical left ventriculotomy approach. With this technique, a much shorter incision of around 1 cm at the apex of the left ventricle may be sufficient for achieving the complete closure of apical muscular VSDs. The transcatheter or perventricular device closure of muscular VSDs has increasingly been performed with good results. Although favorable early and mid-term results of device closure have been reported, this method is not always safer or less invasive than surgical closure. Long-term evaluations should be performed to determine whether the right and left ventricular functions are affected by treatment with relatively large devices in the heart. [ABSTRACT FROM AUTHOR]

A series of composite materials of a new type — foam organoplastics — was obtained from foamed polyimide binders reinforced with Arimid T polyimide felt, and commercially available aromatic monomers were used. Use ofDPO (3,3′,4,4′-diphenyloxidetetracarboxyic acid) dianhydride in the H-complex allows obtaining a melt of lower viscosity (300 Pa-sec), and the viscosity almost does not change at 95°C for 20 min. The viscosity of melts of the H-complexes based on BZP (3,3′, 4,4′-benzophenonetetracarboxylic acid) tends to increase rapidly to the level of 105 Pa·sec, probably due to further “crosslinking” of the H-complex in the conditions of the melt. Replacing the carcinogenic 4,4′-diaminodiphenylmethane (DADPM) diamine by commercially available 4,4′-diaminodiphenyl ether (DADPE) does not significantly alter the rheological behavior of the H-complex melt at 95°C and does not decrease the mechanical characteristics of the foam composites. The mechanical characteristics (bending strength, compressive and shear moduli) of the foam composites based on H-complexes with DPO dianhydride are 1.5 times higher than for the same foam composites using BZP dianhydride. The foam composites based on DPO do not undergo brittle failure but simply bend in bending tests, which can be used to obtain new elastic foam materials. The effect ofnanoparticles on the properties of the foam composites was established. It is expedient to use montmorillonite nanoparticles, which increases the modulus of elasticity and rigidity of the material. [ABSTRACT FROM AUTHOR]

Summary. Experimental testing of piano hammers, which consist of a wood core covered with several layers of compressed wool felt demonstrates, that all hammers have the hysteretic type of the force-compression characteristics. It is shown, that different mathematical hysteretic models can describe the dynamic behavior of the hammer felt. In addition to the four-parameter nonlinear hysteretic felt model, another new three-parameter hysteretic model is presented. Both models are based on the assumption that the hammer felt made of wool is a microstructured material possessing history-dependent properties. The equivalence of these models is proved for all realistic values of hammer velocity. [ABSTRACT FROM AUTHOR]

The article reports that three-dimensional (3D) ultrasound is slowly gaining in popularity. Many anomalies, including those of the fetal face and head, originally seen in conventional two-dimensional sonography are being redescribed using 3D ultrasound. The value of 3D sonography in cases of dacryocystocele is that 3D ultrasound produces fetal images that can be readily recognizable by the layperson. After reviewing a 3D image, one can obtain a better idea of the nature of the deformity and felt more comfortable.

The physicochemical principles underlying the production of felt, cardboard, blocks, panels, and other engineering components using modified glass fibers coated with organosilicon microfilm are presented. In the method developed, the organic component of the microfilm is subjected to thermo-oxidative destruction, which allows one to obtain partially crystallized glass fibers. A remarkable property of these glass fibers is that they can be used for fabrication of components with required shape and structure. [ABSTRACT FROM AUTHOR]