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Calibration Procedures for Orthogonal Superposition Rheology
Published on: November 18, 2020
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OPC和OPC3水模型的切割粘度
1Department of Applied Electronics, Tokyo University of Science, 6-3-1 Niijuku, Katsushika-ku, Tokyo 125-8585, Japan and Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan.
The Journal of chemical physics
|September 12, 2023
概括
最佳点电荷 (OPC) 和OPC3水模型准确地模拟了在更高温度下切割粘度. 虽然低温下低估了粘度,但它们在分子模拟中仍然优于其他模型.
科学领域:
- 计算化学是一种计算化学.
- 分子动力学模拟的模拟.
- 物理化学 物理化学
背景情况:
- 水模型对于准确模拟生物和化学系统至关重要.
- 最佳点电荷 (OPC) 和OPC3模型被广泛使用,因为它们在重现散装水的性能方面非常准确.
- 选择合适的水模型对于可靠的计算研究至关重要.
研究的目的:
- 评估OPC和OPC3水模型在模拟剪切粘度方面的性能.
- 为了评估这些模型在273K至373K的温度范围内的准确性.
- 将它们的准确性与实验数据和其他水模型进行比较.
主要方法:
- 在粘度计算中使用了格林-库博形式主义.
- 进行分子模拟以获得剪切粘度数据.
- 在各种温度下 (273 K373 K) 分析模型性能.
主要成果:
- 在所有测试温度中,OPC和OPC3模型显示出非常相似的粘度值.
- 计算的剪切粘度与310 K以上温度的实验结果非常相符.
- 在较低的温度 (273 K和298 K) 观察到切割粘度的系统低估.
结论:
- OPC和OPC3水模型表现出良好的性能,特别是在生理和更高的温度下.
- 尽管低温下低估了粘度,但这些模型在许多现有水模型上都具有优势.
- 对于精确的低温粘度模拟,可能需要进一步细化.
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