为了提高液体表面张力测量的准确性和稳定性，该文基于悬滴法中完全轮廓法计算原理，改进了二维寻优算法中变量初值的选取方法，并利用权重因子对变量误差函数进行了修正，减小了液滴轮廓偏离点对表面张力测量结果的影响。在温度为25℃，常压条件下，利用改进后的完全轮廓法对水和无水乙醇表面张力进行了测量，结果表明：改进后的完全轮廓法相比原完全轮廓法测量标准差减小了40%，充分证明改进后的完全轮廓法具有更好的测量重复性和稳定性。
The accuracy and stability of surface tension measurements are improved fitting the entire surface profile in the pendent drop method with an algorithm to determine the initial value for two-dimensional optimization. Moreover, the error function was modified by a weighting factor which reduced the influence of the droplet profile deviation point on the surface tension measurement. The full-profile fitting method was used to calculate the surface tension of water and ethanol at 25℃ and atmosphere. The final results show the standard deviation was reduced by 40% compared with the previous method, which verifies the stability and repeatability of this full-profile fitting pendent drop method.
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