Some disperse dyes were microencapsulated by means of in- situ polymerization. These microencapsulated disperse dyes was extracted respectively by ethanol under certain conditions. The controlled-release properties of...Some disperse dyes were microencapsulated by means of in- situ polymerization. These microencapsulated disperse dyes was extracted respectively by ethanol under certain conditions. The controlled-release properties of disperse dyes through the shell of microcapsules were measured by spectrophotometer. According to the results, it was drawn that the type of disperse dyes, the auxiliaries contained in disperse dyes, the quantity of system controlling medium used and the core/shell ratio of microcapsules play important roles in controlling the release properties of microcapsules. The different controlled- release properties of microcapsules, which were prepared under given conditions, however, would in turn influence the performance of microcapsules in multiple-transfer printing.展开更多
Micro-encapsulation is a method of providing probiotic living cells with a physical barrier against adverse environmental conditions. Lactobacillus acidophilus is one of the most effective forms of probiotic bacteria ...Micro-encapsulation is a method of providing probiotic living cells with a physical barrier against adverse environmental conditions. Lactobacillus acidophilus is one of the most effective forms of probiotic bacteria and is commercially available as pure culture and encapsulated form. It is not clear whether the use of micro-encapsulated L. acidophilus will result in yogurt of a better quality compared to non micro-encapsulated L. acidophilus. The objective was to determine the influence of micro-encapsulated L. acidophilus on the characteristics of fat free plain yogurt. Yogurt mixes were pasteurized and at 37℃ were inoculated with Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus and micro-encapsulated L. acidophilus R0052 or non micro-encapsulated L. acidophilus R0052. Yogurt manufacture was replicated three times. Yogurts with micro-encapsulated L. acidophilus R0052 had significantly (P L. acidophilus counts, apparent viscosity, pH and syneresis, of the yogurts with micro-encapsulated L. acidophilus R0052 were not significantly (P L. acidophilus R0052. Use of micro-encapsulated L. acidophilus R0052 resulted in better tasting yogurts probably because of the taste imparted by the trace amounts of the micro-encapsulating material.展开更多
Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and effic...Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and efficiency of the SWA in Ku-band. Firstly, the roughness is simulated using the electromechanical coupled（EC） model. The relationship between roughness and the antenna＇s radiation properties is obtained. For verification, an antenna proto- type is manufactured and tested, and the simulation method is introduced. According to the prototype, a contrasting experiment dealing with the flatness of the radiating plane is conducted to test the simulation method. The advantage of the EC model is validated by comparisons of the EC model and two classical roughness models （sine wave and fractal function）, which shows that the EC model gives a more accurate description model for roughness, the maxi- mum error is 13%. The existence of roughness strongly broadens the beamwidth and raises the side-lobe level of SWA, which is 1.2 times greater than the ideal antenna. In addition, effect of the EC model＇s evaluation indices is investigated, the most affected scale of the roughness is found, which is 1/10 of the working wavelength. The proposed research provides the instruction for antenna designing and manufacturing.展开更多
Polyethylene glycol (PEG) has been used as a phase change material (PCM) to create a thermo-regulating fabric. PEG-600 (Mw) was encapsulated using an in-situ polymerization technique in an oil-in water emulsion with e...Polyethylene glycol (PEG) has been used as a phase change material (PCM) to create a thermo-regulating fabric. PEG-600 (Mw) was encapsulated using an in-situ polymerization technique in an oil-in water emulsion with encapsulating water-immiscible liquid by the reaction of urea with formaldehyde at acidic pH. Both FTIR analysis and DSC studies verified the formation of PEG microcapsules (MC). Melting temperature (Tm) of the microcapsules was found approximately 21°C which was the same as neat PEG. The heat storage capacity of these MCs was determined to be 12.78 J/g by DSC analysis. FTIR analysis of the MCs exhibited the peaks at 3211 cm﹣1, 1650 cm﹣1, and 1400 cm﹣1. These are the characteristic absorption peaks of -NH2, -C=O stretching and -CH bending vibrations, respectively. Fabric coated with PEG microcapsules showed a 20% higher thermal resistance, than the uncoated fabric, when heated on a Sweating Hot Plate (MTNW Corporation).展开更多
The specific heat capacity of working fluid is an important influence factor on heat transfer characteristic of the pulsating heat pipe(PHP).Due to the relatively large specific heat capacity of micro encapsulated pha...The specific heat capacity of working fluid is an important influence factor on heat transfer characteristic of the pulsating heat pipe(PHP).Due to the relatively large specific heat capacity of micro encapsulated phase change material(MEPCM) suspension,a heat transfer performance experimental facility of the PHP was established.The heat transfer characteristic with MEPCM suspension of different mass concentrations(0.5% and 1.0%) and ultra-pure water were compared experimentally.It was found that when the PHP uses MEPCM suspension as its working fluid,operating stability is impoverished under lower heating power and the operating stability is better under higher heating power.At the inclination angle of 90°,the temperature at heating side decreases compared to ultra-pure water and the temperature at heating side decreases with the raising of MEPCM suspension mass concentration.The heat transfer characteristic of the PHP is positively correlated with the inclination angle and the 90° is optimum.The unfavorable effect of the inclination angle decreases with heating power increasing.When the inclination angle is 90°,the PHP with MEPCM suspension at 1.0% of mass concentration has the lowest thermal transfer resistance and followed by ultra-pure water and MEPCM suspension at 0.5% of mass concentration has the highest thermal transfer resistance.When the inclination angles are 60° and30°,the effect of gravity on the flow direction is reduced to 86.6% and 50% of that on the inclination angle of 90°,respectively,and the promoting effect of gravity on the working fluid is further weakened as the inclination angle further decreases.Due to the high viscosity of MEPCM suspension,the PHP with ultra-pure water has the lowest heat transfer resistance.When the inclination angles is 60°,the thermal resistance with MEPCM suspension at0.5% of the mass concentration is lower than that at 1.0% at the heating power below 230 W.The thermal resistance of MEPCM suspension tends to be similar for heating power of 230-250 W.At the heating power above 270 W,the thermal resistance with MEPCM suspension at 1.0% of the mass concentration is lower than that at 0.5%.展开更多
文摘Some disperse dyes were microencapsulated by means of in- situ polymerization. These microencapsulated disperse dyes was extracted respectively by ethanol under certain conditions. The controlled-release properties of disperse dyes through the shell of microcapsules were measured by spectrophotometer. According to the results, it was drawn that the type of disperse dyes, the auxiliaries contained in disperse dyes, the quantity of system controlling medium used and the core/shell ratio of microcapsules play important roles in controlling the release properties of microcapsules. The different controlled- release properties of microcapsules, which were prepared under given conditions, however, would in turn influence the performance of microcapsules in multiple-transfer printing.
文摘Micro-encapsulation is a method of providing probiotic living cells with a physical barrier against adverse environmental conditions. Lactobacillus acidophilus is one of the most effective forms of probiotic bacteria and is commercially available as pure culture and encapsulated form. It is not clear whether the use of micro-encapsulated L. acidophilus will result in yogurt of a better quality compared to non micro-encapsulated L. acidophilus. The objective was to determine the influence of micro-encapsulated L. acidophilus on the characteristics of fat free plain yogurt. Yogurt mixes were pasteurized and at 37℃ were inoculated with Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus and micro-encapsulated L. acidophilus R0052 or non micro-encapsulated L. acidophilus R0052. Yogurt manufacture was replicated three times. Yogurts with micro-encapsulated L. acidophilus R0052 had significantly (P L. acidophilus counts, apparent viscosity, pH and syneresis, of the yogurts with micro-encapsulated L. acidophilus R0052 were not significantly (P L. acidophilus R0052. Use of micro-encapsulated L. acidophilus R0052 resulted in better tasting yogurts probably because of the taste imparted by the trace amounts of the micro-encapsulating material.
基金Supported by National Natural Science Foundation of China(Grant Nos.51305322,51405364,51475348)
文摘Modeling of the roughness in micro-nano scale and its influence have not been fully investigated, however the roughness will cause amplitude and phase errors of the radiating slot, and decrease the precision and efficiency of the SWA in Ku-band. Firstly, the roughness is simulated using the electromechanical coupled（EC） model. The relationship between roughness and the antenna＇s radiation properties is obtained. For verification, an antenna proto- type is manufactured and tested, and the simulation method is introduced. According to the prototype, a contrasting experiment dealing with the flatness of the radiating plane is conducted to test the simulation method. The advantage of the EC model is validated by comparisons of the EC model and two classical roughness models （sine wave and fractal function）, which shows that the EC model gives a more accurate description model for roughness, the maxi- mum error is 13%. The existence of roughness strongly broadens the beamwidth and raises the side-lobe level of SWA, which is 1.2 times greater than the ideal antenna. In addition, effect of the EC model＇s evaluation indices is investigated, the most affected scale of the roughness is found, which is 1/10 of the working wavelength. The proposed research provides the instruction for antenna designing and manufacturing.
文摘Polyethylene glycol (PEG) has been used as a phase change material (PCM) to create a thermo-regulating fabric. PEG-600 (Mw) was encapsulated using an in-situ polymerization technique in an oil-in water emulsion with encapsulating water-immiscible liquid by the reaction of urea with formaldehyde at acidic pH. Both FTIR analysis and DSC studies verified the formation of PEG microcapsules (MC). Melting temperature (Tm) of the microcapsules was found approximately 21°C which was the same as neat PEG. The heat storage capacity of these MCs was determined to be 12.78 J/g by DSC analysis. FTIR analysis of the MCs exhibited the peaks at 3211 cm﹣1, 1650 cm﹣1, and 1400 cm﹣1. These are the characteristic absorption peaks of -NH2, -C=O stretching and -CH bending vibrations, respectively. Fabric coated with PEG microcapsules showed a 20% higher thermal resistance, than the uncoated fabric, when heated on a Sweating Hot Plate (MTNW Corporation).
基金financially supported by National Natural Science Foundation of China (Grant No.52000008)supported by R&D Program of Beijing Municipal Education Commission(Grant No.KM202310016008)+1 种基金Beijing Natural Science Foundation (Grant No.3192042)the Fundamental Research Funds for Beijing University of Civil Engineering and Architecture (Grant No.X20058)。
文摘The specific heat capacity of working fluid is an important influence factor on heat transfer characteristic of the pulsating heat pipe(PHP).Due to the relatively large specific heat capacity of micro encapsulated phase change material(MEPCM) suspension,a heat transfer performance experimental facility of the PHP was established.The heat transfer characteristic with MEPCM suspension of different mass concentrations(0.5% and 1.0%) and ultra-pure water were compared experimentally.It was found that when the PHP uses MEPCM suspension as its working fluid,operating stability is impoverished under lower heating power and the operating stability is better under higher heating power.At the inclination angle of 90°,the temperature at heating side decreases compared to ultra-pure water and the temperature at heating side decreases with the raising of MEPCM suspension mass concentration.The heat transfer characteristic of the PHP is positively correlated with the inclination angle and the 90° is optimum.The unfavorable effect of the inclination angle decreases with heating power increasing.When the inclination angle is 90°,the PHP with MEPCM suspension at 1.0% of mass concentration has the lowest thermal transfer resistance and followed by ultra-pure water and MEPCM suspension at 0.5% of mass concentration has the highest thermal transfer resistance.When the inclination angles are 60° and30°,the effect of gravity on the flow direction is reduced to 86.6% and 50% of that on the inclination angle of 90°,respectively,and the promoting effect of gravity on the working fluid is further weakened as the inclination angle further decreases.Due to the high viscosity of MEPCM suspension,the PHP with ultra-pure water has the lowest heat transfer resistance.When the inclination angles is 60°,the thermal resistance with MEPCM suspension at0.5% of the mass concentration is lower than that at 1.0% at the heating power below 230 W.The thermal resistance of MEPCM suspension tends to be similar for heating power of 230-250 W.At the heating power above 270 W,the thermal resistance with MEPCM suspension at 1.0% of the mass concentration is lower than that at 0.5%.
