波段

Terahertz radiation, which is a kind of electromagnetic wave between the infrared and microwave bands, belongs to far-infrared band. THz time-domain spectroscopy which developed in the 1980\'s has the advantages of high signal to noise ratio, obtaining the absorption coefficient and refractive index of the sample at one time , low energy that can not distroy the biology organise and so on.

太赫兹辐射是指频率位于微波和红外光之间的电磁波，属于远红外波段；20世纪80年代发展起来的THz时域光谱技术，具有信噪比高，能同时获得样品的吸收系数和折射率，能量低，不会对生物组织造成破坏等优点，在材料和生物学等领域得到了迅速的发展和广泛的应用。

After fast Fourier transform , the amplitude and phase of the THz pulse wave is given, then the refractive index and absorption of the material in THz region is extracted.

它以THz辐射作为探测源，利用电光采样或光电导采样方法直接记录THz辐射电场的振幅时间波形，通过傅立叶变换得到测量信号振幅和相位的光谱分布，进而获得材料在THz波段的吸收和色散等信息。

In Chapter 2, the high resolution absorption spectrum of acetylene has been recorded in the visible range by FTS.

在第二章，我们采用傅利叶变换光谱仪记录了乙炔分子在可见波段的高分辨吸收光谱。

For smaller ones, which are expected to be more abundant in number, occultation of background stars by TNOs as a way to study their properties has been proposed but without any definite detection so far.

然而我们可以藉由掩星的方式来估计出一些尺度比较小的但是数量很多的物体，一般来说我们可以藉由光学波段的掩星方法来寻找一些大小差不多在几百公尺到几公里的物体，而且也有一些成果。

The general condition for athermalzing an optical system when the object surface is at finite or infinite distance is deduced in this paper, and the principle and design method of employing a diffractive optical element to athermalize and achromatize an optical system with normalized T-C chart are expounded.

本文推导了物面位于有限和无限距离时实现光学补偿的通用条件，论述了利用归化T-C图设计热补偿和消色差红外光学系统的原理和设计方法，给出了8-12μm波段内、焦距123mm、相对口径F/2.5在20-60℃温度范围内的折衍混合红外光学系统的设计结果和理论评价结果，所述的设计方法可方便地推广到前视红外系统中。

Blazars are one of the most extreme classes of active galactic nucleus, with high luminosity, large amplitude and rapid variability, high and variable polarization, radio core-dominance, and apparent superluminal speeds. Their broad band emission extends from radio up to gamma-ray band, and is dominated by non-thermal process.

中文摘要：在AGNs中，Blazar天体是具有极端性质的一类，它以大幅快速光变、高且变化的偏振、射电核主导、视超光速运动、全波段非热辐射为主要特征。

Blazars are one of the most extreme classes of active galactic nucleus, with high luminosity, large amplitude and rapid variability, high and variable polarization, radio core-dominance, and apparent superluminal speeds.

在活动星系核中，Blazar天体是具有极端性质的一类，它以大幅快速光变、高且变化的偏振、射电核主导、视超光速运动、全波段非热辐射为主要特征。

Ctive Galactic Nucleus is the hottest research on modern astrophysics. Blazars are one of the most extreme classes of active galactic nucleus, with high luminosity, large amplitude and rapid variability, high and variable polarization, radio core-dominance, and apparent superluminal speeds. Their broad band emission extends from radio up to γ-ray band, and dominated by non-thermal process.

GNs是近代天体物理学研究的热门课题，blazar天体是AGNs中具有极端物理性质的一个子类，它以大振幅快速光变、高且变化的偏振、射电核主导、视超光速运动、全波段非热辐射为主要特征。

To 6765 kHz: This is another busy band, this time for aeronautical communications in USB.

这是我们90米的广播波段，主要是一些热带地区的电台使用。

To 5730 kHz: This is another band for aeronautical communications in USB.

到 2498 kHz：这是120米的广播波段，主要是热带地区的广播电台使用。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。