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In this article, a novel wearable and broadband multiple-input and multiple-output (MIMO) antenna is designed for use in several wireless telecommunication/medical systems. In this antenna, two rectangular patches made of cotton fabric (CF) with a dielectric constant equal to 2.23 and a substrate made of a standard felt (SF) with a dielectric constant of 1.3 are employed. The use of two types of flexible and wearable dielectric instead of metal has increased the bandwidth by 7 GHz compared to the microstrip sample. The dimensions of the proposed antenna are equal to 54 × 36 × 2.5 mm3 at 5 GHz. To prove the accuracy of the designs and simulations, the proposed MIMO antenna was fabricated and the measured results are reported. A good agreement was observed between the results of simulation and measurement. The frequency range covered by the proposed MIMO antenna is 1.1–8.6 GHz. Also, the maximum measured gain is equal to 8 dB at 5.5 GHz. Wearability, small size, simple design, low cost, and suitable gain, are among the advantages of the proposed wearable MIMO antenna. [ABSTRACT FROM AUTHOR]

In this article, the pre-oxidized fiber felt composite material was firstly prepared by a mold press process, and the pre-oxidized fiber and resin were used as the reinforcing material and substrate of composite material, respectively. The pretreatment method of the pre-oxidized fiber felt and the impact of the amount of curing agent and the curing pressure on the mechanical properties of the composite material were studied, and the tensile and flexural properties were assessed to optimize the preparation process of composite material. Results show that when the curing agent accounts for 60% of the epoxy resin and the curing pressure is 3 MPa, the best tensile and flexural properties of the prepared composite material are achieved. The mechanical properties for the pretreated composite sheet prepared from pre-oxidized fiber were superior to those for the untreated sheet. [ABSTRACT FROM AUTHOR]

The article discusses two reports published in the "Journal of Applied Polymer Science" and "Journal of Polymer Science," which showed that the strength of adhesive joints is affected by the environment to which they are exposed. The two studies asserted that the surface tension of the wash liquor can significantly affect the rate of felting of polymer-treated wool during washing. The prepolymers used to treat samples of plain-weave worsted fabric and 64s-quality top were: synthappret LKF, adiprene L-42, EP-X-200M and DC-109.

An account is given of an investigation in which thirteen batches of wool tops treated by the chlorine-Hercosett shrinkproofing method were obtained from plant running under industrial conditions. Six lots were completely shrinkproofed. Fabrics made from the others did shrink under certain conditions; the shrinkage rates were then highly dependent on several factors: the yarn linear density, the cover factor, the severity of the wash, and the presence of processing oils. Photographs show that a small proportion of the fibres are still able to migrate through the structure. [ABSTRACT FROM AUTHOR]

An account is given of the use of a strain-gauge system to measure the force exerted on a single needle during the actual punching operation in needle-felting. The variation of this force with distance along the web, test-needle position in the board, web weight, needle penetration, web movement per loom cycle, and fibre orientation in the web is discussed. Finally, an attempt is made to isolate the origin of the punching force and to explain relative values in terms of a known needled-fabric structure. [ABSTRACT FROM AUTHOR]