The non-isothermal crystallization kinetics of modified poly(ethylene terephthalate) (PET) with the function of ultraviolet (UV) protection was studied by means of differential scanning calorimetry. The kinetics of th...The non-isothermal crystallization kinetics of modified poly(ethylene terephthalate) (PET) with the function of ultraviolet (UV) protection was studied by means of differential scanning calorimetry. The kinetics of the modified polymer under non-isothermal crystallization was analyzed by Ozawa equation. The crystallization behavior of the modified polymer obeyed Ozawa theory. The additives in the polymer whose function was UV-resistant acted as crystal nucleus in the processing of crystallization, which resulted in the increase of Avrami index and the crystallization rate of the cooling system.展开更多
A color image formation method is p re sented with thermosensitive liquid crystal polymers. The liquid crystal polymers are capable of reversibly assuming optical states of transparent and scattering lights, and allow...A color image formation method is p re sented with thermosensitive liquid crystal polymers. The liquid crystal polymers are capable of reversibly assuming optical states of transparent and scattering lights, and allow picture-element display areas in two colors at least to be co mposed on a surface. The picture elements within color areas are selected if they correspond to the color which is the spectral transmission center. A heat is applied such that the maximum haze degree of the selected picture elements is greater than that of picture elements corresponding to any of the other colo rs.展开更多
The experimental results of Czochralski silicon (CZ-Si) crystal growth in nitrogen at-mosphere are reported. The chemical reaction between silicon and nitrogen under reduced pres-sures is studied. Nitrogen gas flow un...The experimental results of Czochralski silicon (CZ-Si) crystal growth in nitrogen at-mosphere are reported. The chemical reaction between silicon and nitrogen under reduced pres-sures is studied. Nitrogen gas flow under reduced pressure can eliminate the SiO smokes,and high yield of dislocation-free single crystals can be obtained. Silicon with low carbonconcentration grown by this method exhibits good electrical properties. Heat treatment be-haviours of the Si crystals have been studied. After tri-step intrinsic gettering heat treat-ment, ideal clean denuded zone is formed in Si-wafers.展开更多
Aluminium nitride AlN(100) thin films have been successfully deposited on Si(111) substrates by reactive magnetron sputtering technique. The films have been characterized by XRD to determine their crystalline preferen...Aluminium nitride AlN(100) thin films have been successfully deposited on Si(111) substrates by reactive magnetron sputtering technique. The films have been characterized by XRD to determine their crystalline preferential orientation. The results show that the experimental parameters including total pressure of working gas(N 2+Ar), N 2 partial pressure, target power and the distance from target to substrate affected crystal orientation, deposition rate, and grain size of AlN thin film. The effects of sputtering time and the substrate temperature on AlN film structure have also been investigated. The optimum experimental parameters for AlN(100) thin film deposition are given.展开更多
The hydration characteristics by thermal analysis (DTA) were determined, and an isothermal calorimeter (IC) was used to study the pastes. The experimental results indicate: (1) The main hydration products of SSC are C...The hydration characteristics by thermal analysis (DTA) were determined, and an isothermal calorimeter (IC) was used to study the pastes. The experimental results indicate: (1) The main hydration products of SSC are C-S-H (I) gel with a low Ca/Si ratio, crystalline Thomsonite-type and AFt-type phases containing certain alkali cations; (2) No phases of the AFm-type and high alkaline Ca (OH)(2) in SSC system could benefit the hydrated cements to improve its strength and durability; (3) Crystalline Thomsonite-type and AFt-type phases containing Na+ will greatly reduce free alkali and alleviate the harmness of alkali aggregate reaction (AAR) in SSC system; (4) Similar to ordinary Portland cement (OPC), the hydration process of SSC could be classified into five stage: initial, induction, acceleration, deceleration and decay; (5) Regardless of the activator used, the apparent activation energy is higher with the increased slag in cement system, and the rising temperature could promote the hydration of SSC.展开更多
文摘The non-isothermal crystallization kinetics of modified poly(ethylene terephthalate) (PET) with the function of ultraviolet (UV) protection was studied by means of differential scanning calorimetry. The kinetics of the modified polymer under non-isothermal crystallization was analyzed by Ozawa equation. The crystallization behavior of the modified polymer obeyed Ozawa theory. The additives in the polymer whose function was UV-resistant acted as crystal nucleus in the processing of crystallization, which resulted in the increase of Avrami index and the crystallization rate of the cooling system.
文摘A color image formation method is p re sented with thermosensitive liquid crystal polymers. The liquid crystal polymers are capable of reversibly assuming optical states of transparent and scattering lights, and allow picture-element display areas in two colors at least to be co mposed on a surface. The picture elements within color areas are selected if they correspond to the color which is the spectral transmission center. A heat is applied such that the maximum haze degree of the selected picture elements is greater than that of picture elements corresponding to any of the other colo rs.
基金Project supported by the National Natural Science Foundation of China.
文摘The experimental results of Czochralski silicon (CZ-Si) crystal growth in nitrogen at-mosphere are reported. The chemical reaction between silicon and nitrogen under reduced pres-sures is studied. Nitrogen gas flow under reduced pressure can eliminate the SiO smokes,and high yield of dislocation-free single crystals can be obtained. Silicon with low carbonconcentration grown by this method exhibits good electrical properties. Heat treatment be-haviours of the Si crystals have been studied. After tri-step intrinsic gettering heat treat-ment, ideal clean denuded zone is formed in Si-wafers.
文摘Aluminium nitride AlN(100) thin films have been successfully deposited on Si(111) substrates by reactive magnetron sputtering technique. The films have been characterized by XRD to determine their crystalline preferential orientation. The results show that the experimental parameters including total pressure of working gas(N 2+Ar), N 2 partial pressure, target power and the distance from target to substrate affected crystal orientation, deposition rate, and grain size of AlN thin film. The effects of sputtering time and the substrate temperature on AlN film structure have also been investigated. The optimum experimental parameters for AlN(100) thin film deposition are given.
基金Funded by the State"the Ninth-Five-year Plan "Item (96-535-33-5)
文摘The hydration characteristics by thermal analysis (DTA) were determined, and an isothermal calorimeter (IC) was used to study the pastes. The experimental results indicate: (1) The main hydration products of SSC are C-S-H (I) gel with a low Ca/Si ratio, crystalline Thomsonite-type and AFt-type phases containing certain alkali cations; (2) No phases of the AFm-type and high alkaline Ca (OH)(2) in SSC system could benefit the hydrated cements to improve its strength and durability; (3) Crystalline Thomsonite-type and AFt-type phases containing Na+ will greatly reduce free alkali and alleviate the harmness of alkali aggregate reaction (AAR) in SSC system; (4) Similar to ordinary Portland cement (OPC), the hydration process of SSC could be classified into five stage: initial, induction, acceleration, deceleration and decay; (5) Regardless of the activator used, the apparent activation energy is higher with the increased slag in cement system, and the rising temperature could promote the hydration of SSC.
