Temperature regulating fibers(TRF_(s)) with high enthalpy and high form stability are the key factors for thermal management. However, the enthalpies of most TRFsare not high, and the preparation methods are still at ...Temperature regulating fibers(TRF_(s)) with high enthalpy and high form stability are the key factors for thermal management. However, the enthalpies of most TRFsare not high, and the preparation methods are still at the laboratory scale. It remains a great challenge to use industrial spinning equipment to achieve continuous processing of TRF_(s) with excellent thermal and mechanical properties. Here, polyamide 6(PA6) based TRF_(s) with a sheath-core structure were prepared by bicomponent melt-spinning. The sheath-core TRF(TRF_(sc)) are composed of PA6 as sheath and functional PA6 as core, which are filled with the shape stable phase change materials(ssPCM),dendritic silica@polyethylene glycol(SiO_(2)@PEG). With the aid of the sheath structure, the filling content of SiO_(2)@PEG can reach 30 %, so that the enthalpy of the TRF_(s) can be as high as 21.3 J/g. The ultra-high enthalpy guarantees the temperature regulation ability during the alternating process of cooling and heating. In hot environment, the temperature regulation time is 6.59 min, and the temperature difference is 12.93℃. In addition, the mechanical strength of the prepared TRF_(sc)reaches 2.26 cN/dtex, which can fully meet its application in the field of thermal management textiles and devices to manage the temperature regulation of the human body or precision equipment, etc.展开更多
Waveguide superlattices, a special type of waveguide arrays, can be designed to achieve very low cross talk at submicrometer/subwavelength pitches. The theoretical framework and design rationales for such waveguide su...Waveguide superlattices, a special type of waveguide arrays, can be designed to achieve very low cross talk at submicrometer/subwavelength pitches. The theoretical framework and design rationales for such waveguide superlattices will be presented in depth. Waveguide sidewall roughness can help to deter the coherent coupling between identical waveguides in nearby supercells, but it also induces random fluctuation of transmission.Statistical behavior of the transmission due to roughness in a waveguide superlattice is systematically treated.Complex transmission characteristics due to spectral oscillation and random roughness will be presented, and their evolution with the superlattice length will be analyzed.展开更多
基金financially supported by the National Natural Science Foundation of China (52073047)the Science and Technology Commission of Shanghai Municipality (20JC1414900)+1 种基金the Program of Shanghai Technology Research Leader (20XD1433700)the INTERNATIONAL COOPERATION Fund of the Science and Technology Commission of Shanghai Municipality (20520740800)。
文摘Temperature regulating fibers(TRF_(s)) with high enthalpy and high form stability are the key factors for thermal management. However, the enthalpies of most TRFsare not high, and the preparation methods are still at the laboratory scale. It remains a great challenge to use industrial spinning equipment to achieve continuous processing of TRF_(s) with excellent thermal and mechanical properties. Here, polyamide 6(PA6) based TRF_(s) with a sheath-core structure were prepared by bicomponent melt-spinning. The sheath-core TRF(TRF_(sc)) are composed of PA6 as sheath and functional PA6 as core, which are filled with the shape stable phase change materials(ssPCM),dendritic silica@polyethylene glycol(SiO_(2)@PEG). With the aid of the sheath structure, the filling content of SiO_(2)@PEG can reach 30 %, so that the enthalpy of the TRF_(s) can be as high as 21.3 J/g. The ultra-high enthalpy guarantees the temperature regulation ability during the alternating process of cooling and heating. In hot environment, the temperature regulation time is 6.59 min, and the temperature difference is 12.93℃. In addition, the mechanical strength of the prepared TRF_(sc)reaches 2.26 cN/dtex, which can fully meet its application in the field of thermal management textiles and devices to manage the temperature regulation of the human body or precision equipment, etc.
基金Young Thousand Talents program of ChinaJiangsu Specially Appointed Professor programPriority Academic Program Development of Jiangsu Higher Education Institutions
文摘Waveguide superlattices, a special type of waveguide arrays, can be designed to achieve very low cross talk at submicrometer/subwavelength pitches. The theoretical framework and design rationales for such waveguide superlattices will be presented in depth. Waveguide sidewall roughness can help to deter the coherent coupling between identical waveguides in nearby supercells, but it also induces random fluctuation of transmission.Statistical behavior of the transmission due to roughness in a waveguide superlattice is systematically treated.Complex transmission characteristics due to spectral oscillation and random roughness will be presented, and their evolution with the superlattice length will be analyzed.
