光化学样本棒用于不弹性中子散射
Daniel Vong1, Eric C Novak2, Adam J Moulé3
1Department of Materials Science and Engineering, University of California Davis, 1 Shields Ave., Davis, California 95616, USA.
The Review of scientific instruments
|August 4, 2023
概括
研究人员开发了用于光活性材料现场无弹性中子散射 (INS) 研究的新工具. 这一突破使光化学反应和激发状态的研究成为可能,扩大了中子散射科学的能力.
科学领域:
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
- 摄影化学的使用.
背景情况:
- 原子和分子运动是材料性质的基础,通过振动或声子来研究.
- 光学光谱学 (拉曼,IR,INS) 探测材料特性,而探测方法研究激发状态.
- 不弹性中子散射 (INS) 由于实验挑战,对光活性材料的研究受到限制.
研究的目的:
- 克服实验的局限性,阻碍了INS对光活性材料的实地研究.
- 为了使光化学反应和激发状态的研究使用INS.
- 扩大INS的应用范围到光活性系统.
主要方法:
- 设计和实施两个新的光化学样本棒.
- 在树国家实验室使用VISION仪器进行INS测量.
- 通过在现场进行色素的光二聚化和光电复合物的光聚化进行演示.
主要成果:
- 使用INS成功开发了实验装置,用于在现场进行光化学研究.
- 证明了研究实时光二分化和光聚合过程的能力.
- 克服了中子和光子透深度不匹配和光学接入的先前限制.
结论:
- 开发的样本棒显著扩大了INS研究的范围.
- 允许对光活性材料,激发状态和光启动反应进行现场研究.
- 开辟了理解材料中的光物质相互作用的新途径.
相关概念视频
Atomic Emission Spectroscopy: Lab
198
AES is a powerful analytical technique, especially effective when used with plasma sources, producing abundant spectra in characteristic emission lines. The Inductively Coupled Plasma (ICP), in particular, yields superior quantitative analytical data due to its high stability, low noise, low background, and minimal interferences under optimal experimental conditions. However, newer air-operated microwave sources are emerging as promising alternatives that could be more cost-effective than...
198
Atomic Absorption Spectroscopy: Radiation and Light Sources
434
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...
434
UV–Vis Spectrometers
1.4K
The absorbance of UV and visible (UV–visible) radiations is measured using a UV–visible spectrophotometer. Deuterium lamps, which emit UV radiation, and tungsten lamps, which produce radiation in the visible region, are used as light sources in UV–visible spectrophotometers. A monochromator or prism is used for diffraction grating, i.e., to split the incoming radiation into different wavelengths. A system of slits is used to focus the desired wavelength on the sample cell.
1.4K
Flame Photometry: Overview
666
Flame photometry, also known as flame emission spectrometry, is a technique used for the qualitative and quantitative analysis of elements present in a sample using a flame as the source of excitation energy. The concept of flame photometry was realized in the early 1860s by Kirchhoff and Bunsen, who discovered that specific elements emit characteristic radiation when excited in flames. The first instrument developed for this purpose was used to measure sodium (Na) in plant ash using a Bunsen...
666
Atomic Spectroscopy: Absorption, Emission, and Fluorescence
1.1K
Atomic spectroscopy is a vital tool in elemental analysis, both qualitatively and quantitatively. It can be broadly divided into optical spectroscopy, mass spectroscopy, and X-ray spectroscopy methods. The optical spectroscopic methods are atomic absorption spectroscopy (AAS), atomic emission spectroscopy (AES), and atomic fluorescence spectroscopy (AFS). The first step in all three methods is atomization, where the solid, liquid, or solution-phase samples are converted into gas-phase atoms and...
1.1K
Atomic Emission Spectroscopy: Instrumentation
524
The instrumentation of atomic emission spectrometry (AES) involves various components, including atomization devices that convert samples into gas-phase atoms and ions. There are two main types of atomization devices: continuous and discrete atomizers. Continuous atomizers, like plasmas and flames, introduce samples in a constant stream, while discrete atomizers inject individual samples using syringes or autosamplers. The most common discrete atomizer is the electrothermal atomizer.
524


