纳米塑料(NPs)与纳米活性炭(NAC)在环境中的共迁移会影响其环境行为。本研究探究了在模拟水溶液中,电解质和pH对不同表面改性的聚苯乙烯纳米颗粒(PSNPs)与NAC异型凝聚的影响。研究发现,由于静电斥力不同,在300 mM NaCl中,随着pH升高,APS...纳米塑料(NPs)与纳米活性炭(NAC)在环境中的共迁移会影响其环境行为。本研究探究了在模拟水溶液中,电解质和pH对不同表面改性的聚苯乙烯纳米颗粒(PSNPs)与NAC异型凝聚的影响。研究发现,由于静电斥力不同,在300 mM NaCl中,随着pH升高,APS(带氨基的PSNPs)与BPS(无表面修饰的PSNPs)的凝聚速率都呈大体下降趋势;在10 mM CaCl_(2)中,APS与NAC在高pH时发生凝聚,BPS与NAC在所有pH下均稳定分散。本研究有助于理解NPs与NAC在水环境中的异型凝聚行为。展开更多
以乳清分离蛋白(whey protein isolate,WPI)与乳铁蛋白(lactoferrin,LF)乳状液形成微聚集体与转谷氨酰胺酶酶促交联微聚集体,以期提高体系流变特性。通过微射流分别制备WPI和LF乳状液,二者混合后,乳状液微滴之间发生异型聚集效应,通过...以乳清分离蛋白(whey protein isolate,WPI)与乳铁蛋白(lactoferrin,LF)乳状液形成微聚集体与转谷氨酰胺酶酶促交联微聚集体,以期提高体系流变特性。通过微射流分别制备WPI和LF乳状液,二者混合后,乳状液微滴之间发生异型聚集效应,通过转谷氨酰胺酶交联结合形成具有特定三维空间网络结构的微聚集体。研究结果表明:WPI与LF乳状液发生异型聚集,最大程度的聚集和最高物理稳定性体系发生在50%LF-50%WPI微滴形成的微聚集体。异型聚集效应改变了乳状液的流变特性,与单一WPI和LF乳状液相比,50%LF-50%WPI微聚集体流变学特性黏度值分别为单一乳状液的3.72倍和2.2倍,通过转谷氨酰胺酶交联,乳状液微聚集体的黏度值为原来的11.4倍。因此,基于异型聚集效应结合酶促交联,可提高食品体系的流变特性,为开发食品脂质替代物提供了一定的理论支持。展开更多
Heteroaggregates composed of cationic porphyrin, meso-tetra(p-trimethylamino)porphyrin iodide, its sine complex and anionic phthalocyanine sodium hydroxygallium 4,4',4 '',4 ''-tetrasulfonated phtha...Heteroaggregates composed of cationic porphyrin, meso-tetra(p-trimethylamino)porphyrin iodide, its sine complex and anionic phthalocyanine sodium hydroxygallium 4,4',4 '',4 ''-tetrasulfonated phthalocyanine have been investigated by absorption and fluorescence spectroscopy. It has been found that both free base cationic porphyrin and its zinc complex can form very stable heterodimers with anionic phthalocyanine in water, methanol and dimethylformamide. The stability of the aggregate depends on the polarity as well as the ligation ability of the solvent. No evidence of higher aggregates was detected. Besides axial coordination, steric hindrance which influences the relative orientation of the macrocycles are considered.展开更多
文摘纳米塑料(NPs)与纳米活性炭(NAC)在环境中的共迁移会影响其环境行为。本研究探究了在模拟水溶液中,电解质和pH对不同表面改性的聚苯乙烯纳米颗粒(PSNPs)与NAC异型凝聚的影响。研究发现,由于静电斥力不同,在300 mM NaCl中,随着pH升高,APS(带氨基的PSNPs)与BPS(无表面修饰的PSNPs)的凝聚速率都呈大体下降趋势;在10 mM CaCl_(2)中,APS与NAC在高pH时发生凝聚,BPS与NAC在所有pH下均稳定分散。本研究有助于理解NPs与NAC在水环境中的异型凝聚行为。
文摘以乳清分离蛋白(whey protein isolate,WPI)与乳铁蛋白(lactoferrin,LF)乳状液形成微聚集体与转谷氨酰胺酶酶促交联微聚集体,以期提高体系流变特性。通过微射流分别制备WPI和LF乳状液,二者混合后,乳状液微滴之间发生异型聚集效应,通过转谷氨酰胺酶交联结合形成具有特定三维空间网络结构的微聚集体。研究结果表明:WPI与LF乳状液发生异型聚集,最大程度的聚集和最高物理稳定性体系发生在50%LF-50%WPI微滴形成的微聚集体。异型聚集效应改变了乳状液的流变特性,与单一WPI和LF乳状液相比,50%LF-50%WPI微聚集体流变学特性黏度值分别为单一乳状液的3.72倍和2.2倍,通过转谷氨酰胺酶交联,乳状液微聚集体的黏度值为原来的11.4倍。因此,基于异型聚集效应结合酶促交联,可提高食品体系的流变特性,为开发食品脂质替代物提供了一定的理论支持。
基金Project supperted the National Science Foundation of China and the Laboratory of Excited State Processes,Changchun Institute of Physics,Chinese Academy of Science.
文摘Heteroaggregates composed of cationic porphyrin, meso-tetra(p-trimethylamino)porphyrin iodide, its sine complex and anionic phthalocyanine sodium hydroxygallium 4,4',4 '',4 ''-tetrasulfonated phthalocyanine have been investigated by absorption and fluorescence spectroscopy. It has been found that both free base cationic porphyrin and its zinc complex can form very stable heterodimers with anionic phthalocyanine in water, methanol and dimethylformamide. The stability of the aggregate depends on the polarity as well as the ligation ability of the solvent. No evidence of higher aggregates was detected. Besides axial coordination, steric hindrance which influences the relative orientation of the macrocycles are considered.
