This work describes experiments on thermal dynamics of pure H2O excited by hydrodynamic cavitation, which has been reported to facilitate the spin conversion of para- and ortho-isomers at water interfaces. Previous measurements by NMR and capillary methods of excited samples demonstrated changes of proton density by 12-15%, the surface tension up to 15.7%, which can be attributed to a non-equilibrium para-/ortho- ratio. Beside these changes, we also expect a variation of heat capacity. Experiments use a differential calorimetric approach with two devices: one with an active thermostat for diathermic measurements, another is fully passive for long-term measurements. Samples after excitation are degassed at -0.09MPa and thermally equalized in a water bath. Conducted attempts demonstrated changes in the heat capacity of experimental samples by 4.17%--5.72% measured in the transient dynamics within 60 min after excitation, which decreases to 2.08% in the steady-state dynamics 90-120 min after excitation. Additionally, we observed occurrence of thermal fluctuations at the level of 10^-3 C relative temperature on 20-40 min mesoscale dynamics and a long-term increase of such fluctuations in experimental samples. Obtained results are reproducible in both devices and are supported by previously published outcomes on four-photon scattering spectra in the range from -1.5 to 1.5 cm^-1 and electrochemical reactivity in CO2 and H2O2 pathways. Based on these results, we propose a hypothesis about ongoing spin conversion process on mesoscopic scales under weak influx of energy caused by thermal, EM or geomagnetic factors; this enables explaining electrochemical and thermal anomalies observed in long-term measurements.

翻译：本文描述了纯水在流体空化激发下的热动力学实验，该激发过程已被报道可促进水界面处对位与邻位异构体的自旋转换。已有研究通过核磁共振和毛细管法测量激发态样品，发现质子密度变化达12-15%，表面张力变化高达15.7%，这归因于非平衡的对位/邻位比例。除这些变化外，我们预期热容量也会发生改变。实验采用差示量热方法，使用两种装置：一种配备主动恒温器进行透热测量，另一种为全被动装置用于长期测量。激发后的样品在-0.09MPa下脱气并在水浴中进行热平衡。实验尝试表明，在激发后60分钟内的瞬态动力学中，实验样品的热容量变化达4.17%--5.72%，而在激发后90-120分钟的稳态动力学中，该变化降至2.08%。此外，我们观察到在20-40分钟的介观动力学尺度上，相对温度出现10^-3摄氏度的热涨落现象，且实验样品中此类涨落呈现长期增长趋势。两种装置获得的结果均具可重复性，且与先前发表的-1.5至1.5 cm^-1范围内四光子散射光谱以及CO2和H2O2路径中的电化学反应活性结果相一致。基于这些结果，我们提出假设：在由热、电磁或地磁因素引起的弱能量流入条件下，介观尺度上存在持续的自旋转换过程，这为长期测量中观察到的电化学和热学异常现象提供了解释依据。