ストレス誘発の渦巻き線は,スメクティックA液晶のプラスチックの流れでヘリクシングの雪崩を起こします
Science (New York, N.Y.)
|February 3, 1995
まとめ
ダイナミック・フォース測定は,層トポロジカルイベントの際にスメクティックA物質の時間依存反応を明らかにする. 層の変化に先行する雪崩のようなシグネチャは,スクルーの変位を含むリラクゼーションメカニズムを示唆しています.
科学分野:
- 物理 物理学 物理学とは
- マテリアルサイエンス 材料科学
- ソフトマター物理学 ソフトマター物理学
背景:
- スメクティックA液晶は,外部のストレスに対して複雑な反応を示します.
- 層の追加または除去などのトポロジカルイベントは,材料のダイナミクスを理解するために不可欠です.
研究 の 目的:
- トポロジカルイベント中のスメクティックA液晶の時間依存の表面力反応を調査する.
- 単一のスメクティック層の変化に関連するダイナミクスを特徴づけるために.
主な方法:
- ダイナミックな表面力測定を用いた.
- 分析は,層の追加/除去中の分離変化の時間依存性に焦点を当てました.
主要な成果:
- レイヤー・ノーマル・ストレスは,時間依存の反応を誘発した.
- シングルレイヤーの大きさの厚さジャンプは,ゆっくりとした加速 (数百秒) が先行した急速な分離変化 (~1秒) を示しました.
- このダイナミックなシグネチャーは,雪崩のプロセスに似ています.
結論:
- 観測された雪崩のようなダイナミクスは,リラックスメカニズムを示唆しています.
- このメカニズムは,スメクティック・オーダーパラメータにおける渦線 (スクルーの変位) のグラバーソン・クレム・ブルドン不安定性と一致しています.
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