まとめ
エル・チホン火山は,硫黄や水銀のような大量に揮発性元素を放出しました. これらの元素,特にヒ素は,より小さな火山灰の粒子に集中していました.
科学分野:
- 地質化学 地質化学
- 大気科学 大気科学
- 火山学 火山学とは
背景:
- メキシコのエル・チホン火山は,1982年に噴火した.
- 火山の羽根には,微量ガス,粒子,および酸性揮発性物質が含まれています.
研究 の 目的:
- El Chichón火山の羽根の微量ガスと微粒子を分析するために.
- 微量元素の排出量とその粒子の大きさの分布を定量化するために.
主な方法:
- 火山の羽根を航空機で採取する.
- 元素濃度のための中性子活性化分析.
- 流量推定のための硫黄排出量率への正常化.
主要な成果:
- 硫化水素は,硫黄ガスの支配的成分でした.
- 揮発性元素 (S,Cl,As,Se,Br,Sb,I,W,Hg) は,高濃度 (60-20,000x) の羽根に含まれていた.
- アルゼン,アンチモン,セレニウムは,小さな粒子 (<3ミクロメートル) で発見されました.
- 激しい噴火からのストラトスフィアの灰は,静かな羽毛物質よりも高い元素濃度 (10-30倍) を示した.
結論:
- 火山からの放射は,大気組成に大きな影響を与える.
- 微量元素を粒子に分割する方法は,元素と粒子のサイズによって異なります.
- 激しい噴火は,平流層の元素負荷により大きな影響を及ぼします.
関連する概念動画
01:29Atomic Emission Spectroscopy: Lab
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...
01:30Atomic Emission Spectroscopy: Interference
In atomic emission spectroscopy (AES), high-temperature atomizers excite a broad range of elements and molecules that generate complex emissions from sources such as oxides, hydroxides, and flame combustion products in the flame or plasma. Several strategies can be employed to minimize spectral interferences caused by overlapping emission lines or bands. These include increasing instrument resolution, choosing alternative emission lines, optimally placing the detector in low-background regions,...
01:22Atomic Emission Spectroscopy: Instrumentation
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.
01:19Inductively Coupled Plasma Atomic Emission Spectroscopy: Principle
Inductively coupled plasma (ICP) is the most widely used plasma source in atomic emission spectroscopy (AES), also known as Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The ICP source, or torch, consists of three concentric quartz tubes with argon gas flowing through them. A spark from a Tesla coil initiates the ionization of argon, generating a high-temperature plasma.
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
01:19Inductively Coupled Plasma–Mass Spectrometry (ICP–MS): Overview
In inductively coupled plasma–mass spectrometry (ICP–MS), an inductively coupled plasma (ICP) torch is used as an atomizer and ionizer. Solid samples are dissolved and volatilized before being introduced into the high-temperature argon plasma, while solution samples are nebulized and passed through the high-temperature argon plasma. Plasma dissociates the analytes and ionizes their component atoms to form a mixture of positive ions and molecular species. The positive ions are then passed on to...
01:02Flame Photometry: Overview
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...