Abstract: Embodiments of the present invention provide method and devices for signaling transmission in unlicensed band. The method comprising determining a signal transmission pattern, which defines time and frequency resources for transmitting at least one signal in a first frequency band; signaling, via a second frequency band, the signal transmission pattern to a first device; and transmitting the at least one signal via the first frequency band, to the first device, according to the signal transmission pattern; wherein a transmission of one of the at least one signal is skipped if time and frequency resource for the transmission defined by the signal transmission pattern is detected as busy. Corresponding methods and devices for receiving a signal which is transmitted using above method are also disclosed.

Abstract: The present invention pertains to isocyanate-terminated prepolymers prepared from cyclic alkylene carbonates, the method for preparing the same and the use thereof in preparing polyurethanes, polyureas, polyurethane elastomer, and polyurethane mouldings. The incorporation of cyclic alkylene carbonates into the isocyanate-terminated prepolymers of the present invention improves their liquid stability at low temperatures while maintaining their physical properties.