Most published reports on ascorbic acid (AA) degradation during food storage and heat preservation suggest that it follows first-order kinetics. Deviations from this pattern include Weibullian decay, and exponential drop approaching finite nonzero retention. Almost invariably, the degradation rate constant's temperature-dependence followed the Arrhenius equation, and hence the simpler exponential model too. A formula and freely downloadable interactive Wolfram Demonstration to convert the Arrhenius model's energy of activation, E_a, to the exponential model's c parameter, or vice versa, are provided. The AA's isothermal and non-isothermal degradation can be simulated with freely downloadable interactive Wolfram Demonstrations in which the model's parameters can be entered and modified by moving sliders on the screen. Where the degradation is known a priori to follow first or other fixed order kinetics, one can use the endpoints method, and in principle the successive points method too, to estimate the reaction's kinetic parameters from considerably fewer AA concentration determinations than in the traditional manner. Freeware to do the calculations by either method has been recently made available on the Internet. Once obtained in this way, the kinetic parameters can be used to reconstruct the entire degradation curves and predict those at different temperature profiles, isothermal or dynamic. Comparison of the predicted concentration ratios with experimental ones offers a way to validate or refute the kinetic model and the assumptions on which it is based.

中文翻译：

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模拟抗坏血酸的降解动力学

有关食品存储和保温过程中抗坏血酸（AA）降解的大多数已发表的报告表明，它遵循一级动力学。与这种模式的偏差包括Weibullian衰减和接近有限非零保留的指数下降。退化速率常数的温度依赖性几乎始终遵循Arrhenius方程，因此也遵循更简单的指数模型。公式和可免费下载的交互式Wolfram演示，用于转换Arrhenius模型的激活能量E _a，提供给指数模型的c参数，反之亦然。可以通过可免费下载的交互式Wolfram演示来模拟AA的等温和非等温降级，其中可以通过在屏幕上移动滑块来输入和修改模型的参数。在先验已知降解遵循第一或其他固定顺序动力学的情况下，可以使用终点法，原则上也可以使用连续点法，通过比传统方式少得多的AA浓度测定来估算反应的动力学参数。最近，Internet上已提供了使用这两种方法进行计算的免费软件。一旦以这种方式获得，动力学参数可用于重建整个降解曲线，并预测在不同温度曲线（等温或动态）下的降解曲线。预测浓度比与实验浓度比的比较提供了一种验证或反驳动力学模型及其基础假设的方法。