Fe3O4 magnetic nanoparticles with diameters varying from 10 to 426 nm were synthesized and characterized.Heating effects of Fe3O4 magnetic nanoparticles under radiofrequency capacitive field(RCF) with frequency of 27....Fe3O4 magnetic nanoparticles with diameters varying from 10 to 426 nm were synthesized and characterized.Heating effects of Fe3O4 magnetic nanoparticles under radiofrequency capacitive field(RCF) with frequency of 27.12 MHz and power of 60-150 W were investigated.When the power of RCF is lower than 90 W,temperatures of Fe3O4 magnetic nanoparticles(75-150 mg/mL) can be raised and maximal temperatures are all lower than 50 ℃.When the power of RCF is 90-150 W,temperatures of Fe3O4 magnetic nanoparticles can be quickly raised and are all obviously higher than those of normal saline and distilled water under the same conditions.Temperature of Fe3O4 magnetic nanoparticles can even reach 70.2 ℃ under 150 W RCF.Heating effects of Fe3O4 magnetic nanoparticles are related to RCF power,particle size and particle concentration.展开更多
The measurement system is the main equipment of the project.Based on the characteristic of experiment system,a sensor array is designed,and used to continually acquire the global magnetic field.A scientific scheme is ...The measurement system is the main equipment of the project.Based on the characteristic of experiment system,a sensor array is designed,and used to continually acquire the global magnetic field.A scientific scheme is developed to get the signal processing and temperature compensation for nondirective weak magnetic field.The software of sampling control system is given,which is complied using C language in Labwindows/CVI.Taking computer as main engine,the system can acquire the nondirective weak magnetic field automatically and continuously use the sensor array,the change of magnetic field can be shown in real-time and intuitively.展开更多
为探讨低压静电场(low voltage electrostatic field,LVEF)处理对蝴蝶兰切花保鲜效果的影响,该研究以蝴蝶兰切花品种“天堂鸟”为试验对象,探究了低压静电场处理对蝴蝶兰切花瓶插期间观赏品质、理化指标及相关酶活性的变化,并通过低场...为探讨低压静电场(low voltage electrostatic field,LVEF)处理对蝴蝶兰切花保鲜效果的影响,该研究以蝴蝶兰切花品种“天堂鸟”为试验对象,探究了低压静电场处理对蝴蝶兰切花瓶插期间观赏品质、理化指标及相关酶活性的变化,并通过低场核磁共振(low-field nuclear magnetic resonance,LF-NMR)技术分析蝴蝶兰切花的水分迁移和水分流失情况。结果表明:瓶插第28天时,与对照组相比,低压静电场组的蝴蝶兰切花能保持较好的外观形态,其鲜质量和花径分别显著(P<0.05)提高4.88%、4.98%,可溶性糖含量和可溶性蛋白含量分别显著(P<0.05)提高了0.75、4.09 mg/g,相对电导率和丙二醛(malondialdehyde,MDA)含量分别显著(P<0.05)降低了31.53%、21.96 nmol/g,超氧化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)和过氧化氢酶(catalase,CAT)的活性峰值分别显著(P<0.05)提高了19.58、20.77、20.21 U/g,同时,结果表明低压静电场处理延缓了蝴蝶兰切花的水分迁移和水分流失现象。综上,低压静电场处理延缓了蝴蝶兰切花的品质劣变,该研究结果可为其他切花的保鲜应用提供一定的理论依据和技术参考。展开更多
基金Projects(30571779,10775085) supported by the National Natural Science Foundation of ChinaProject(Z07000200540704) supported by Beijing Municipal Science and Technology Commission,China
文摘Fe3O4 magnetic nanoparticles with diameters varying from 10 to 426 nm were synthesized and characterized.Heating effects of Fe3O4 magnetic nanoparticles under radiofrequency capacitive field(RCF) with frequency of 27.12 MHz and power of 60-150 W were investigated.When the power of RCF is lower than 90 W,temperatures of Fe3O4 magnetic nanoparticles(75-150 mg/mL) can be raised and maximal temperatures are all lower than 50 ℃.When the power of RCF is 90-150 W,temperatures of Fe3O4 magnetic nanoparticles can be quickly raised and are all obviously higher than those of normal saline and distilled water under the same conditions.Temperature of Fe3O4 magnetic nanoparticles can even reach 70.2 ℃ under 150 W RCF.Heating effects of Fe3O4 magnetic nanoparticles are related to RCF power,particle size and particle concentration.
基金Project(10672191)supported by the National Natural Science Foundation of ChinaProject(06JJ2059)supported by the Provincial Natural Science Foundation of Hunan,ChinaProject(KF0607) supported by the Key Laboratory of Low Dimensional Materials and Application Technology (Xiangtan University),Ministry of Education,China
文摘The measurement system is the main equipment of the project.Based on the characteristic of experiment system,a sensor array is designed,and used to continually acquire the global magnetic field.A scientific scheme is developed to get the signal processing and temperature compensation for nondirective weak magnetic field.The software of sampling control system is given,which is complied using C language in Labwindows/CVI.Taking computer as main engine,the system can acquire the nondirective weak magnetic field automatically and continuously use the sensor array,the change of magnetic field can be shown in real-time and intuitively.