The basic theories of the frequency synthesis , PLL , DDS, DDS + PLL are introduced first in this paper.

The transmitterof DHF uses DDS to synthesize frequency.

发射机采用直接数字频率合成器(DDS)生成频率,具有精度高、频率跳变速度快的特点.

This article describes the design of a linear sweeping frequency signal generator using DDS technology.

本文介绍了利用DDS来产生线性扫频信号的射频信号发生单元的设计.

Microbiological degradation is an effective and environment-friendly method to eliminate DDT pollution.

微生物降解是一种有效的环境友好型去除DDT污染的手段.

The house is regularly spraying with DDT.

房屋是定期用DDT喷洒.

Led to the ban of DDT because of its highly toxic nature.

导致禁用DDT,因为它有很高的毒性.

The insects can be exterminated by spraying DDT.

可以用喷撒滴滴涕的方法大量杀死这种昆虫.

DDT sprayed into the air kills mosquitoes and other insect pests.

喷射到空气中的ddt能杀死蚊子和其他有害昆虫.

The underneath cargo is'stained contaminated the DDT dust.

以下货物被DDT原粉灰尘污染.

In 1873, the chemical DDT was first synthesized.

1873年, 化学物质滴滴涕(DDT)首次合成.

They're spraying DDT. to kill the insects.

他们在喷洒滴滴涕杀虫.

DDT molecules in water tend to migrate to the surface.

在水中滴滴涕分子趋向于向水面移动.

Take DDT, a pesticide that can damage the nerous system.

如DDT, 一种可损伤神经系统的杀虫剂.

Encouraged the use of DDT indoors, but discouraged it for outdoor use.

鼓励在室内使用DDT, 但不鼓励在户外使用.

Many insects have became resistant to DDT.

很多昆虫对DDT都有了抵抗力.

Thousands of new chemicals , like DDT, soon resided in every living tissue.

DDT等无数新的化学品, 很快渗进了每个活组织.

Many microorganisms possess the ability to dehydrohalogenate DDT to DDE.

许多微生物使滴滴涕脱卤化氢变为滴滴依.

Then came the golden days of DDT ( dichlorodiphenyltrichloroethane ).

然后就是 DDT 的黄金年代.

Technical Documentation fee is for delivery DDU Destination Airport.

其技术资料价格为ddu目的地机场交付价.

The DDU term was added in the 1990 version of Incoterms.

此到指定目的地税前交货价(DDU)条件被加入于1990年版国贸条规中.

Fewer workers are needed to solder circuit boards.

焊接电路板需要的工人更少了。