In this study,the sol-gel method was introduced to prepare the composite phase change material (CPCM). The CPCM was added to fabric with coating techniques and the thermal activity of modified fabric was studied. In a...In this study,the sol-gel method was introduced to prepare the composite phase change material (CPCM). The CPCM was added to fabric with coating techniques and the thermal activity of modified fabric was studied. In addition,the thermal property and the microstructure of CPCM were also discussed in detail by means of polarization microscope and differential scanning calorimeter,respectively. According to the analysis of main influencial factors of the property of CPCM,the optimal preparing technique was determined. It was proved that CPCM could exhibit a good thermal property while phase transformation process took place,and a better appearance of the fabric modified with CPCM could be obtained due to the fact that in a warm circumstance,the liquid-state phase change material could be firmly enwrapped and embedded in the three-dimensional network all the time during the phase transformation. Besides,the fabric treated with CPCM had a high phase-transition enthalpy and an appropriate phase-transition temperature. As a result,a desirable temperature-adjustable function appeared.展开更多
The great major applications of thermal isolation are in the strip of drops and averages temperatures (up to 180 ℃), which is used from aggressive materials to the nature, such as glass wool, rock wool, polystyrene...The great major applications of thermal isolation are in the strip of drops and averages temperatures (up to 180 ℃), which is used from aggressive materials to the nature, such as glass wool, rock wool, polystyrene, EPS among others. In spite of the effectiveness in the retention of the flow of heat, such materials possess considerable cost and they are discarded for long years to be decomposed. In that context, to adapt to the world politics about the preservation of the environment, a study began with intention of developing a material composite with thermal properties, originating from insulating industrial residues. In this research, the behavior of this composite was analyzed, when it submitted traction efforts. For this, a term-mechanic was used (DMA), where the composite was differentiated under variation temperatures. It was also certain that the gradient temperature of the composite was the source of heat, the conductivity and thermal diffusion. Consequently, the function of the answers of the system was possible to be observed with the deformation of the composite with the tension and temperature variation, as well as the temperature gradient for each proportion of the composite.展开更多
A new kind of organic-inorganic hybrid HfO2/SiO2 sol-gel material with a large thermo-optic coefficient and a wide linear tunable temperature range has been developed for fabrication of a long period waveguide grating...A new kind of organic-inorganic hybrid HfO2/SiO2 sol-gel material with a large thermo-optic coefficient and a wide linear tunable temperature range has been developed for fabrication of a long period waveguide grating (LPWG) filter, whose parameters were optimized and designed by using finite difference time domain (FDTD) simulations. The LPWG filter, a periodic rectangle-corrugated grating structure, was easily fabricated with soft-lithography technique. At a temperature range from 19~C to 70~C, the fabricated LPWG filter element demonstrated a high temperature sensitivity of about 6.5 nm/~C and a wide linear tunable temperature range of 51℃, so that it can be used as a precise thermometer. Our results are useful for the designs of LPWG filters for the implementation of a wide range of thermo-optic functions.展开更多
基金Fujian Province I mportant Science and Technology Development Fund,China (No.2005Z17)
文摘In this study,the sol-gel method was introduced to prepare the composite phase change material (CPCM). The CPCM was added to fabric with coating techniques and the thermal activity of modified fabric was studied. In addition,the thermal property and the microstructure of CPCM were also discussed in detail by means of polarization microscope and differential scanning calorimeter,respectively. According to the analysis of main influencial factors of the property of CPCM,the optimal preparing technique was determined. It was proved that CPCM could exhibit a good thermal property while phase transformation process took place,and a better appearance of the fabric modified with CPCM could be obtained due to the fact that in a warm circumstance,the liquid-state phase change material could be firmly enwrapped and embedded in the three-dimensional network all the time during the phase transformation. Besides,the fabric treated with CPCM had a high phase-transition enthalpy and an appropriate phase-transition temperature. As a result,a desirable temperature-adjustable function appeared.
文摘The great major applications of thermal isolation are in the strip of drops and averages temperatures (up to 180 ℃), which is used from aggressive materials to the nature, such as glass wool, rock wool, polystyrene, EPS among others. In spite of the effectiveness in the retention of the flow of heat, such materials possess considerable cost and they are discarded for long years to be decomposed. In that context, to adapt to the world politics about the preservation of the environment, a study began with intention of developing a material composite with thermal properties, originating from insulating industrial residues. In this research, the behavior of this composite was analyzed, when it submitted traction efforts. For this, a term-mechanic was used (DMA), where the composite was differentiated under variation temperatures. It was also certain that the gradient temperature of the composite was the source of heat, the conductivity and thermal diffusion. Consequently, the function of the answers of the system was possible to be observed with the deformation of the composite with the tension and temperature variation, as well as the temperature gradient for each proportion of the composite.
基金supported by the Natural Science Foundation of Guangdong Province,China (Grant Nos. 8251063101000007,10151063101000009 and 9451063101002082)the Scientific & Technological Plan of Guangdong Province (Grant Nos. 2008B010200004,2010B010600030 and 2009B011100003)+4 种基金the National Natural Science Foundation of China (Grant Nos. 61078046 and 10904042)the Key Project of Chinese Ministry of Education (Grant No. 210157)the Scientific & Technological Project of Education Department of Hubei Province (Grant No. D20101104)the Fundamental Research Funds for the Central Universities (Grant No. HUST 2010MS069)Program for New Century Excellent Talents in University,China (Grant No. 07-0319)
文摘A new kind of organic-inorganic hybrid HfO2/SiO2 sol-gel material with a large thermo-optic coefficient and a wide linear tunable temperature range has been developed for fabrication of a long period waveguide grating (LPWG) filter, whose parameters were optimized and designed by using finite difference time domain (FDTD) simulations. The LPWG filter, a periodic rectangle-corrugated grating structure, was easily fabricated with soft-lithography technique. At a temperature range from 19~C to 70~C, the fabricated LPWG filter element demonstrated a high temperature sensitivity of about 6.5 nm/~C and a wide linear tunable temperature range of 51℃, so that it can be used as a precise thermometer. Our results are useful for the designs of LPWG filters for the implementation of a wide range of thermo-optic functions.