相关实验视频
Updated: Jul 23, 2025

13:31
High Speed Sub-GHz Spectrometer for Brillouin Scattering Analysis
Published on: December 22, 2015
15.1K
在2.8 GHz的粗冰石回散系数库
Djordje Mirkovic1,2, Dusan S Zrnic3,4
1Cooperative Institute for Severe and High-Impact Weather Research and Operations (CIWRO), Norman, OK, USA. djordje.mirkovic@noaa.gov.
Scientific data
|July 13, 2023
概括
一个新的图书馆提供了非球形冰石的回散数据,这对于美国的天气雷达分析至关重要. 该工具有助于使用计算电磁方法了解冰的特征.
科学领域:
- 大气科学 大气科学
- 气象学 天气学
- 电磁学 电磁学 电磁学 电磁学
背景情况:
- 准确的石散射模型对于天气雷达解释至关重要.
- 现有的模型经常与非球形和粗的冰石特性作斗争.
研究的目的:
- 为非球形冰石开发一个反向散射系数库.
- 为国家气象局使用的S波段雷达频率提供相关数据.
- 为了使计算电磁 (CEM) 建模与更简单的方法和观察进行比较.
主要方法:
- 开发一种计算电磁 (CEM) 方法来建模冰石.
- 包括可变的轴比,冰大小 (5-100毫米) 和表面粗度.
- 将CEM结果与传统方法 (如T矩阵方法) 的比较.
主要成果:
- 对于非球形冰石的S波段反散系数的一个全面的库.
- 证明CEM方法对具有极端轴比的水星有效,而其他方法失败.
- 计算的极度测量变量可以直接与雷达观测结果进行比较.
结论:
- 开发的图书馆解决了对非球形冰散射数据的关键需求.
- 对于复杂的冰石形状和表面,CEM建模提供了更强大的方法.
- 这种资源对美国的冰研究和天气雷达应用非常有价值.
相关概念视频
Attenuated Total Reflectance (ATR) Infrared Spectroscopy: Overview
426
Attenuated total reflectance (ATR) infrared spectroscopy is a powerful analytical technique used to study the composition of materials. It is widely employed in chemistry, materials science, forensic science, and other fields where sample characterization is required. ATR has several advantages over traditional transmission IR spectroscopy, including the requirement of little to no sample preparation and the ability to analyze a wide range of samples.
The ATR process begins by directing a beam...
The ATR process begins by directing a beam...
426
Atomic Absorption Spectroscopy: Interference
849
Interference leads to systematic error in atomic absorption (AA) measurements by enhancing or diminishing the analytical signal or the background. These interferences can be grouped into three main categories: spectral interference, chemical interference, and physical interference.
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
849
Atomic Absorption Spectroscopy: Radiation and Light Sources
443
Atomic absorption spectroscopy (AAS) relies on the Beer-Lambert law, which requires that the radiation source emits a narrow range of wavelengths to match the absorption characteristics of the analyte atom. The primary criteria for choosing an appropriate radiation source in AAS is to provide a precise and intense emission at specific wavelengths that will allow accurate detection of the analyte.
Two common narrow-range 'line' sources used in AAS are hollow-cathode lamps (HCLs) and...
Two common narrow-range 'line' sources used in AAS are hollow-cathode lamps (HCLs) and...
443
Precipitation Gravimetry
6.7K
Precipitation gravimetry is based on converting an analyte into a sparingly soluble precipitate, which is separated by filtration and weighed. An ideal precipitate should be pure, insoluble, of known composition, and easily filtered from the reaction mixture.
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
6.7K
IR Spectroscopy: Hooke's Law Approximation of Molecular Vibration
1.4K
A covalently bonded heteronuclear diatomic molecule can be modeled as two vibrating masses connected by a spring. The vibrational frequency of the bond can be expressed using an equation derived from Hooke's law, which describes how the force applied to stretch or compress a spring is proportional to the displacement of the spring. In this case, the atoms behave like masses, and the bond acts like a spring.
According to Hooke's law, the vibrational frequency is directly proportional to...
According to Hooke's law, the vibrational frequency is directly proportional to...
1.4K
2D NMR: Heteronuclear Single-Quantum Correlation Spectroscopy (HSQC)
768
Heteronuclear single-quantum correlation spectroscopy (HSQC) is a 2D NMR technique that reveals one-bond correlations between hydrogen and a heteronucleus. The HSQC experiment is similar to the heteronuclear correlation experiment (HETCOR) but is more sensitive. In the HSQC spectrum, the proton chemical shift is plotted on the horizontal F2 axis, while the 13C chemical shift is plotted on the vertical F1 axis. The corresponding proton and 13C spectra are also shown. The HSQC contour plot does...
768

