动态光散射样品高度不超过15毫米为了避免温度梯度

The reason why the height of cell in dynamic laser scattering should lower than 15 mm is to avoid temperature slope above the chamber.

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以Malvern Nano ZS为例，虽然日常测试中，样品高度高于15毫米不影响测试，但是据Malvern工程师讲“样品的高度上限是因为温度。因为载样腔是由铝，以及样品池下的Peltier座组成。完全装满的样品池可能会在样品上部有温度梯度（尤其是对室温的高温或低温，温度对折射率、流变、布朗运动和粒径有强烈影响；译注），因此短一些好。而激光的位置是底部以上8毫米。因此最佳取决于样品的数量，不过通常15毫米最好，10毫米足够。“

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Take Malvern Nano Zs as example, although in the routine test, the height of cell seemed not affecting the result of test, while the Malvern engineer said

"The matter of sample height in cell is temperature.The cell holder is made by Aluminium and Peltier sits under the cell

holder.Fully filled sample cell may have temperature slope against to the height, then shorter (smaller) is better. And also, the laser radiation/detection height is about 8mm from the bottom. Best height should be determined by sample mass, but  generaly, 15mm is better and 10mm is enough."