Previously published experimental viscosity data at low density, originally obtained using all-quartz oscillating-disk viscometers for 12 gases and vapors in the temperature range between 297 K and 691 K, were re-evaluated after an improved re-calibration. The relative combined expanded (k = 2) uncertainty of the re-evaluated data is 0.2% near room temperature and increases to 0.3% at higher temperatures. The re-evaluated data for sulfur hexafluoride, methanol, n-pentane, n-hexane, n-heptane, neopentane, cyclohexane, benzene, toluene, p-xylene, phenol, and triethylamine were arranged in approximately isothermal groups and converted into quasi-isothermal viscosity data using a first-order Taylor series in temperature. Then, they were evaluated by means of a series expansion truncated at first order to obtain the zero-density and initial density viscosity coefficients, η⁽⁰⁾ and η⁽¹⁾. When the number of isothermal data or their quality was not adequate, the Rainwater–Friend theory for the initial density dependence of the viscosity was additionally used to derive η⁽⁰⁾ and η⁽¹⁾ values. Finally, reliable η⁽⁰⁾ and η⁽¹⁾ values, preferably obtained from the isotherms, were recommended as reference values for the 12 gases and vapors in the measured temperature range to be applied when generating any new viscosity formulation.

中文翻译：

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零密度极限中的粘度推荐值及其对十二种气体和蒸气的初始密度依赖性：从297 K和691 K之间的实验重新审视

经过改进的重新校准后，重新评估了以前发布的低密度实验粘度数据，该数据最初是使用全石英振荡盘粘度计针对297 K和691 K之间的温度范围内的12种气体和蒸汽获得的。重新评估数据的相对组合扩展后的不确定度（k = 2）在室温附近为0.2％，在较高温度下增加为0.3％。为六氟化硫，甲醇，重新估算数据Ñ戊烷，Ñ己烷，Ñ庚烷，新戊烷，环己烷，苯，甲苯，p-二甲苯，苯酚和三乙胺按近似等温基团排列，并使用温度的一阶泰勒级数转换为准等温粘度数据。然后，通过一阶截断的级数展开法对它们进行评估，以获得零密度和初始密度粘度系数η ^（0）和η ^（1）。当等温数据的数量或它们的质量不足时，还额外使用了Rainwater-Friend理论来确定粘度的初始密度依赖性，从而得出η ^（0）和η ^（1）值。最后，可靠的η ^（0）和η ^（1） 当生成任何新的粘度配方时，建议使用最好从等温线获得的最佳值作为在所测温度范围内要使用的12种气体和蒸气的参考值。