转换开关

The sampling of the inductor current is synchronized with the PWM signal in synchronous buck converter for both turn-on and turn-off.

在降压转换器中，开关切换时电感电流的取样讯号将会与脉宽调变(pulse width modulation， PWM)讯号同步。

At the same time the effection of some important recombinations are discussed and the relation of photoconduction versus time is given. In chapter 4, Auston circuit, blumlein pulse forming line, multiplier of pulse forming line are introduced and give their differentiates.

在第四章中，分析各种以光导开关为核心器件的电脉冲成形电路：Auston电路、Blumlein脉冲成形线、层叠线倍压器，对其输出转换效率进行比较，并进行实验研究。

The RhoA oncogene , have been revealed in recent years, are closely related to various malignant tumours. RhoA, belonging to Rho family, is one member of the ras superfamily, whose encoding production, namely RhoA protein, pertaining to micromolecular mass GTP conjugated protein family, in GTP conjunctive active form and GDP conjunctive unreactive form. It exist in the latter form in normal cells and the switch of the two forms enables them to educe functions, paralleling"molecular switch", the diminutive G protein in activated state being able to activate the wink dromo-iter to work functions, which is in the resemblance of process during which the Ras genic mutation induces its continous activations.

RhoA是近年来新发现的与多种恶性肿瘤密切相关的癌基因，RhoA属于Rho亚家族，是ras基因超家族的一员，其编码产物RhoA蛋白属于小分子量GTP结合蛋白族，分为GTP结合的活性型和GDP结合的非活性型两类，在正常细胞内以GDP结合的非活性型存在，两种活性形式之间的转换使他们能够发挥一种类似&分子开关&的作用，活性态的小G蛋白能激活下游的信号传导通路，行使其功能。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。