使用THz光谱捕获NaCl纳米颗粒的冷干燥动态
Katsuhiro Ajito1, Yuko Ueno2, Jae-Young Kim1
1NTT Device Technology Laboratories , NTT Corporation , Atsugi 243-0198 , Japan.
Journal of the American Chemical Society
|October 24, 2018
概括
研究人员在冷干燥过程中发现了单位细胞大小的化 (NaCl) 颗粒. 这一发现为制造超细制药粉末的冷干燥技术提供了新的可能性.
科学领域:
- 物理化学
- 材料科学
- 晶体学
背景情况:
- 在低温下,化 (NaCl) 溶液形成化 (NaCl·2H2O),作为食品和药品冷干燥研究的模型.
- 了解冷过程中的NaCl结晶对于优化冷干燥过程至关重要.
研究的目的:
- 研究水溶液冷过程中NaCl结晶的初始阶段.
- 使用先进的光谱技术识别NaCl水合物形成的前体物质.
主要方法:
- 使用特拉赫兹 (THz) 光谱检测和分析NaCl溶液冷过程中的颗粒.
- 分析的重点是识别单位细胞大小的粒子及其光谱特征.
主要成果:
- 在NaCl溶液冷过程中,在冰中检测到单位细胞大小的NaCl颗粒,这些颗粒之前没有被记录在相图中.
- 两个类型的转移性单元细胞大小的NaCl颗粒被确定为NaCl·2H2O形成的前体.
- 这些前体粒子在太赫兹频谱中表现出明显的吸收峰值.
结论:
- 单细胞大小的NaCl颗粒的存在凸显了结过程中NaCl结晶的复杂性.
- 这一发现为冷干燥过程提供了新的见解.
- 它为开发新型冷干燥技术开辟了道路,用于生产纳米大小的颗粒,例如具有增强溶解性的超细制药粉末.
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