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Jute fibre, a natural composite of cellulose, hemicellulose and lignin, occupies the second place to cotton in economic importance. Recently many attempts have been made to produce fine jute blended yarn with other textile fibres. In this paper, the two types of jute/cotton blended yarn whose jute and cotton fibres were respectively blended at the opening and drawing stages were spun by using the ring spinning technology. The tensile properties of both blended yarn at gauge lengths from 150 mm to 500 mm were investigated, and the evenness and imperfections for both blended yarn were also evaluated. The results show that the draw frame blended yarn was of better quality than the opener blended yarn. The breaking tenacities of both blended yarn increased with the decrease in the gauge length. The equations derived from two-parameter Weibull distribution and based on experimental strength at length of 300 mm can predict the breaking strength of both blended yarn accurately. The scale effect study indicates that the opener blended yarn strength decreased more sharply than draw frame blended yarn as the gauge length increased.

This study aims to explore the formation mechanism of aerodynamic noise of a high-speed maglev train and understand the characteristics of dipole and quadrupole sound sources of the maglev train at different speed levels.

Based on large eddy simulation (LES) method and Kirchhoff–Ffowcs Williams and Hawkings (K-FWH) equations, the characteristics of dipole and quadrupole sound sources of maglev trains at different speed levels were simulated and analyzed by constructing reasonable penetrable integral surface.

The spatial disturbance resulting from the separation of the boundary layer in the streamlined area of the tail car is the source of aerodynamic sound of the maglev train. The dipole sources of the train are mainly distributed around the radio terminals of the head and tail cars of the maglev train, the bottom of the arms of the streamlined parts of the head and tail cars and the nose tip area of the streamlined part of the tail car, and the quadrupole sources are mainly distributed in the wake area. When the train runs at three speed levels of 400, 500 and 600 km·h⁻¹, respectively, the radiated energy of quadrupole source is 62.4%, 63.3% and 71.7%, respectively, which exceeds that of dipole sources.

This study can help understand the aerodynamic noise characteristics generated by the high-speed maglev train and provide a reference for the optimization design of its aerodynamic shape.

Copyright law has been oft-criticized for its unintended consequences. This paper retells three “tales of the unintended” concerning the 1976 Copyright Act, the present U.S. copyright statute. The first tale focuses on fair use, the second on statutory damages, and the third on formalities. From these three tales, the paper draws five different morals that provide insights into the ongoing process of copyright reform. These insights will enable policymakers and commentators to rethink the ongoing and future development of copyright law.

Wool, mainly composed of keratin, is a relatively high-grade clothing material. Although woollen textile has the advantages of high wearing comfort and excellent warmth retention property as we have known, its inherent disadvantage of easy pilling has easy puzzled people for a long time. Most of the existing technologies for pilling resistance are not eco-friendly or severely damaged the internal structure of wool.

In this work, a controlled and effective surface treatment method was proposed to controllable micro-dissolution the scale layers of wool with minor damage to its internal structure, thereby improving the anti-pilling property of wool. Thiourea dioxide (TD) is used as a dissolving agent to swell and dissolve wool surface flakes. After TD treatment, the morphology changes of wool fibers were observed by scanning electron microscope (SEM) and methylene blue staining. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used to characterize the structural changes of TD wool. At the same time, the anti-pilling properties and wettability of wool fabrics were tested.

The results show that the wool scale layer is destroyed after TD treatment, which reduces the friction between fibers and improves the anti-pilling performance of wool fabrics. The methylene blue-stained images further demonstrate that low concentrations of TD can damage the superficial scale layer of wool without significant loss of strength.

This method is simple, eco-friendly and economical, and opens up a new direction for the surface treatment of wool fabrics.