| 1. | - the home research lnstitute , hfl 家政研究协会, hfi |
| 2. | The home research lnstitute , hfl 家政研究协会, hfi |
| 3. | The achievement of transgenetic plants would provide a scientific basis and lay firm foundation for the transformation of hfl and hf2 gene into other ornamental flowers 转基因植株的获得,将为以后hf1 、 hf2基因转化其它名贵花卉作物提供科学依据,并打下良好的基础。 |
| 4. | Flavonoid - 3 ' , 5 ' - hydroxylase ( f3 ' , 5 ' h ) corresponding to the genetic loci hfl and hf2 , a member of the cytochrome p450 family , is the key enzyme in the anthocyanin biosynthesis , which is generally required for blue or purple flowers 本研究以紫蓝色矮牵牛基因组dna为模板,利用pcr技术获得了两个扩增产物,分别将其克隆至pgem - teasyvector上,进行了全序列分析。 |
| 5. | Hfl inverters in discontinuous current mode ( dcm ) are extended to those in continuous current mode ( ccm ) , which is very important for improving the conversion efficiency . the reason is that the peak current and rms current of power switches can be reduced sharply 本文将工作于dcm方式的单级高频链逆变电路扩宽到ccm工作方式,仿真和试验结果表明ccm模式下流过功率管电流峰值和有效值明显减小,这对提高逆变电路的效率具有重要意义。 |
| 6. | By the simulation results , it is verified to have excellent performance . a class of uncertain nonlinear systems which can be transformed into strict feedback nonlinear systems is investigated based on feedback linearization approach of differential geometry . an adaptive robust controller with l2 - gain is proposed by using backstepping technique . the numerical method is given and it is proved to be practical by simulation results . lt is a more practical method to solve hji for a special nonlinear system because the problem to solve hji is very difficult in general case , and only get the approximate solution when it can be solved . an effective method to solve hji is presented for a class of nonlinear system which is ordinary 考虑到一般情况下,求解hji是非常困难的,并且也只能得到近似解,因此,在系统设计时,针对具体非线性系统的特殊结构以求解hfl是系统设计的一种行之有效的方法,基于以上考虑,对一类具有广泛工程背景的非线性系统,提出了一种求解hfl的有效方法,便于实际应用。最后,从波能谱的角度,研究随机海浪的仿真问题,给出了船舶横摇仿真中需要的随机海浪有效波倾角的仿真方法。 |
| 7. | The experiment result shows that conversion efficiency in ccm is improved by 2 percent compared with that in dcm , although the on - resistance of winding in ccm is more than that in dcm . the analysis of open - loop transfer function in both dcm and ccm shows that pull - push hfl inverter at ccm 微分补偿网络的推挽高频链逆变电路在输出从空载变化到额定阻性负载变化的过程中,逆变电路工作模式从dcm变化到ccm模式,实验结果表明电路在这两种模式下都能输出稳定的正弦电压,且具有较高的稳态精度。 |
| 8. | Push - pull current mode hfl inverter also is composed of four power switches . the simulation and experiment of a 500va experimental prototype indicates that this circuit has the advantages of less components , simple topology , the ability of four quadrant operation and high efficiency . the inverter does not need the symmetry of the components " parameters and can be applied to dc to ac conversion with single low input voltage source 推挽双向电流源高频链逆变电路也是由四个功率管组成, 500va的原理样机的仿真和实验研究结果表明,该电路元器件少、电路拓扑简单、能够四象限可靠运行、变换效率高,并不要求器件参数的完全对称,适合于输入电压较低的场合。 |
| 9. | To isolate hfl - , hf2 gene encoding flavonoid - 3 ' , 5 ' - hydroxylase ( f3 ' , 5 ' h ) from petunia hybrida of the purple flower , we used a polymerase chain reaction ( pcr ) amplification using the genomic dna as a template . the result indicated that the hfl dna was 2797bp in total length and encoded 506 amino - acid , containing three extron and two intron ; hf2 dna was 2223bp in total length and encoded 509 amino - acid , containing three extron and two intron . comparison of the sequence with genbank databases revealed that hfl dna and hf2 dna shared significant nucleotides identity ( 98 . 97 % and 99 . 04 % respectively ) and amino - acid identity ( 99 . 41 % and 99 . 41 % respectively ) Hf1dna全长2797bp ,包括3个外显子, 2个内含子,其中一个开放阅读框架( orf )编码506个氨基酸,与文献报道的序列相比较,具有98 . 97核苷酸同源性与99 . 41氨基酸同源性: hf2dna全长2223bp ,包括3个外显子, 2个内含子,其中一个开放阅读框架( orf )编码509个氨基酸,与文献报道的核苷酸同源率为99 . 04以及氨基酸同源率为99 . 41 。 |
| 10. | The half - bridge bi - directional current mode hfl inverter can realize dc to ac conversion in only one stage . the half - bridge bi - directional current mode hfl inverter succeeds to the advantages of full - bridge hfl inverter but uses fewer power switches , which reduces the costs of switches " driver circuit 半桥双向电流源高频链逆变电路只需一级功率变换即可实现直流到交流的转换,在继承全桥高频链逆变电路优点的同时,使用的功率管更少,功率管的减小同时降低了驱动电路的成本。 |