まとめ
二次氷結晶の生成は,超冷却された雲の滴が-5°Cで移動する標的に凍結すると発生します. より高い生産率は,より大きな雲の滴 (直径≥24マイクロメートル) の増加した蓄積と相関しています.
科学分野:
- 大気科学 大気科学
- クラウド物理学 クラウド物理
- 気象学 気象学 気象学
背景:
- 超冷却雲滴は,0°C以下の液体の水滴である.
- 氷の結晶の形成は,降水過程において極めて重要です.
- 二次氷の生成メカニズムは完全に理解されていません.
研究 の 目的:
- 二次氷結晶形成の条件を調査する.
- 滴の蓄積と氷結晶の生成の関係を定量化するために.
主な方法:
- 超冷却された雲のシミュレートされた蓄積は,5°Cの移動するターゲットに落ちます.
- 二次氷結晶の生成速度を観測し,測定した.
主要な成果:
- 二次氷結晶は,移動する表面上の超冷却ドロップの凍結中に放出されます.
- 二次氷結晶の生成率は,直径24マイクロメートル以上の雲滴の蓄積率と正比例しています.
結論:
- 超冷却された大きな雲の滴の蓄積は,二次氷結晶の重要な源である.
- このプロセスを理解することは,雲のモデルと降雨予測の改善の鍵です.
関連する概念動画
Types of Coprecipitation
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Sometimes, ions in a crystal lattice can undergo isomorphous replacement by inclusions of similar charge and size. For...
Sometimes, ions in a crystal lattice can undergo isomorphous replacement by inclusions of similar charge and size. For...
Crystal Growth: Principles of Crystallization
Crystallization is a phase transformation process in which crystals are precipitated from a supersaturated solution or formed from other sources. During crystallization, atoms or molecules arrange themselves into a well-defined, rigid crystal lattice to minimize energy.
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent – the...
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent – the...
Precipitate Formation and Particle Size Control
In precipitation gravimetry, the precipitating agent should react specifically or selectively with the analyte. While a specific reagent reacts with the analyte alone, a selective reagent can react with a limited number of chemical species.
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
The obtained precipitate should be either a pure substance of known composition or easily converted to one by a simple process, such as ignition or drying. In addition, the precipitate should be insoluble and easily filterable. In general, filterability...
Precipitation Processes
The experimental conditions in a gravimetric analysis should be optimized to maximize the particle size and purity of the obtained precipitate. Ideally, the concentration of the precipitating reagent should be low with effective stirring to maintain low relative supersaturation for the growth of large crystals. In homogeneous precipitation, the precipitant is slowly generated by a chemical reaction in the solution to avoid local reagent excesses. For example, urea decomposes gradually to...
Recrystallization: Solid–Solution Equilibria
Recrystallization is a purification technique used to separate impurities from solid compounds. In this technique, no chemical reactions occur. Instead, it exploits physical properties only, specifically, the solubility differences between the desired compound and impurities, either at a single temperature or at different temperatures, and under other selected conditions. The solid-solution equilibrium (solubility equilibrium) of each component in the solution represents a binary phase...
Precipitation of Ions
Predicting Precipitation
The equation that describes the equilibrium between solid calcium carbonate and its solvated ions is:
The equation that describes the equilibrium between solid calcium carbonate and its solvated ions is:


