関連する実験動画
Updated: Jul 12, 2026

08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
まとめ
液体の流動性は,分子膨張が臨界体積 (V(0) を超えることと直接関係しており,自己拡散と粘度に影響を与えます. この関係は,様々な液体に対して当てはまり,液体状態の理論的モデルに異議を唱える.
科学分野:
- 物理化学 物理化学
- マテリアルサイエンス 材料科学
背景:
- 液体の行動,特にその流動性は,様々な化学的および物理的プロセスを理解するために不可欠です.
- 既存の理論モデルでは,液体が流動性を示す条件を過度に単純化することがあります.
研究 の 目的:
- 液体の流動性と分子膨張の間の定量的な関係を確立するために.
- 液体の粘度および拡散率の決定における分子混雑と排斥力の役割を調査する.
主な方法:
- 粘度 (eta) とモラル体積 (V) と臨界体積 (V(0) を関連付ける比例方程式を開発した.
- 通常のパラフィン (C3H8からC7H16) と他の液体 (ベンゼン,四塩化炭素,リン,二酸化炭素,クロロフォーム,水銀) の粘度データを分析した.
主要な成果:
- 粘度はモール体積の相対的な膨張に逆比例する: 1/eta = B[(V - V(0)) / V(0) ].
- 比例定数 (B) は,より短い正常パラフィンでは一貫しているが,鎖の長さを増すにつれて減少する.
- 他の液体におけるBの変動が観察され,排斥力との相関が示唆された.
- 液体は10%未満の膨張でも流体であることが示され,いくつかの理論に反する.
結論:
- 液体の流動性は,基本的には,最小包装容量 (V(0) を超える分子膨張と関連しています.
- 排斥力は,様々な種類の液体の流動性において重要な役割を果たします.
- 拡散性はV = V ((0) で始まり,温度に依存し,溶液と溶媒の相互作用の影響を受けます.
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