Splitting energy (Δε)-controlled thermally activated reversed phase transformation from the low-lying dark state to the high-lying transition-allowed state of H-aggregation plays a key role in the organic ultralong room-temperature phosphorescence.

Compression garments are made of elastic fabric, which is used for operational reasons and clinical applications for treating venous ulceration, deep vein thrombosis or burns. The constant pressure of compression garments exerted on human body is very essential, and the success of the application is extremely dependent on this pressure. However, elastic fabric has a characteristic of hysteresis which contributes to the pressure decay during wearing. In this study, dynamic pressure attenuation is investigated experimentally. Dynamic pressure decreases with the repeated extension and recovery; its pressure attenuation increases as the extension level varied from 10% to 40%. The effects of fabric parameters on dynamic pressure at 1st test cycle and on dynamic pressure attenuation are also analyzed, such as spandex feeding rate and fabric structure. These results provide a better understanding of characteristics of elastic fabric used for making compression garments, and are beneficial for practitioners with scientific developments and for effective applications.

Purpose -The paper aims to develop a system and measuring method for investigating the dynamic pressure behavior of compression garments. Design/methodology/approach -The dynamic pressure behavior measurement, realized by use of the self-designed system, is a direct measuring method, which is based on a rigid hemisphere with five pressure sensors distributed on its surface. The dynamic pressure is measured over time under the process of fabric 3D deformation. The pressure distributions at the basic five sites are accepted as the measuring results. The dynamic stiffness index can be calculated from dynamic pressure profile and 3D deformation of compression garments. Findings -The measuring system records the pressure-time curve and pressure-deformation curve. The dynamic pressure stiffness index expresses the change in pressure owing to the change in elongation of compression fabrics. The pressure measuring system and the index provide much information in the field of compression garment assessment. Research limitations/implications -Another characteristic that was not mentioned but important is pressure hysteresis, which can give the information about pressure decay when fabrics undergoing repeated stretch and relaxation. The influence factors of hysteresis and its role in compression garments also requires further research. Originality/value -To determine and characterize the dynamic pressure behavior of compression garment under 3D deformation, this study develops a measuring system and defines a new index. The measuring system can be used in scientific research institutes and factories, contribute to optimize process parameters and quality control of compression garment.

Organic ultralong room-temperature phosphorescence (OURTP) has boomed recent advances of organic optoelectronics with the significant breakthrough in facilitating the intersystem crossing and stabilization of triplet excitons of purely organic materials. However, it remains a challenge in revealing the inherent mechanism of OURTP and the general molecular design principles of OURTP materials have yet to be reached, largely owing to the rather complicated and varied OURTP molecular structures. Here, we propose a facile strategy to design efficient OURTP materials by simply introducing a cyano group (CN) on benzene. On the basis of these very simple OURTP molecules, it was found that the simultaneously enhanced intersystem crossing and aggregation coupling are two intrinsic prerequisites in realizing the efficient OURTP. The first observation of the excimer emission from the stabilized singlet excited states offers an important evidence for the mechanism study of OURTP, and the direct CN substitution on the benzene ring would be highly instructive for designing efficient OURTP molecules.