This paper introduces the design of doubly fed system for conveyor belt motor, the system adopts stator flux orientation vector control technology and AC-AC inverter motor speed and power factor control, and carried o...This paper introduces the design of doubly fed system for conveyor belt motor, the system adopts stator flux orientation vector control technology and AC-AC inverter motor speed and power factor control, and carried on the test in transmission field. This paper introduces in detail the structure and characteristic of DSP system, and gives a design scheme of Doubly Fed Speed Control System of motor based on this chip.展开更多
Design and development of efficient non-viral gene delivery systems is critical to overcome various barriers for effective intracellular gene delivery.Eight new spermine-based protonatable surfactants were designed,sy...Design and development of efficient non-viral gene delivery systems is critical to overcome various barriers for effective intracellular gene delivery.Eight new spermine-based protonatable surfactants were designed,synthesized and evaluated as non-viral pH-sensitive gene carriers.These carriers formed stable complexes with plasmid DNA at an N/P ratio as low as 2.The sizes of the carrier/pDNA nanoparticles (N/P = 12) were in the range of 90–130 nm,smaller than that of Lipofectamine2000/pDNA nanoparticles.The pDNA nanoparticles of the carriers exhibited substantially increased hemolysis when pH decreased from 7.4 to 5.5.The DNA nanoparticles had low cytotocixity,similar to that of Lipofectamine-2000/pDNA nanoparticles.The pH-sensitive gene carriers with no helper lipids resulted in much higher intracellular transfection and gene expression in U87 cells than Lipofectamine-2000.[N,N′-Bis(oleoylcysteinyl)(β-alanyl-α-lysyl)]-spermine monoamide (SKACO) resulted in the highest luciferase transfection efficiency,more than 400 times higher than that of Lipofectamine-2000,and GFP expression in 71% of transfected U87 cells.SKACO was identified as a promising lead carrier for efficient gene delivery.These spermine-based pH-sensitive amphiphilic carriers have a potential to be further developed as efficient non-viral multifunctional gene delivery systems.展开更多
文摘This paper introduces the design of doubly fed system for conveyor belt motor, the system adopts stator flux orientation vector control technology and AC-AC inverter motor speed and power factor control, and carried on the test in transmission field. This paper introduces in detail the structure and characteristic of DSP system, and gives a design scheme of Doubly Fed Speed Control System of motor based on this chip.
文摘Design and development of efficient non-viral gene delivery systems is critical to overcome various barriers for effective intracellular gene delivery.Eight new spermine-based protonatable surfactants were designed,synthesized and evaluated as non-viral pH-sensitive gene carriers.These carriers formed stable complexes with plasmid DNA at an N/P ratio as low as 2.The sizes of the carrier/pDNA nanoparticles (N/P = 12) were in the range of 90–130 nm,smaller than that of Lipofectamine2000/pDNA nanoparticles.The pDNA nanoparticles of the carriers exhibited substantially increased hemolysis when pH decreased from 7.4 to 5.5.The DNA nanoparticles had low cytotocixity,similar to that of Lipofectamine-2000/pDNA nanoparticles.The pH-sensitive gene carriers with no helper lipids resulted in much higher intracellular transfection and gene expression in U87 cells than Lipofectamine-2000.[N,N′-Bis(oleoylcysteinyl)(β-alanyl-α-lysyl)]-spermine monoamide (SKACO) resulted in the highest luciferase transfection efficiency,more than 400 times higher than that of Lipofectamine-2000,and GFP expression in 71% of transfected U87 cells.SKACO was identified as a promising lead carrier for efficient gene delivery.These spermine-based pH-sensitive amphiphilic carriers have a potential to be further developed as efficient non-viral multifunctional gene delivery systems.
