An electrolyte cathode atmospheric glow discharge atomic emission spectroscopy(ELCAD-AES) has been developed to determine the hardness of water. By the standard curves of Mg and Ca, the concentration curves of Mg and Ca measurement were obtained. The limits of detection of Mg and Ca were 0.2 and 0.8 mg/L, respectively. The precision and recovery were experimentally elucidated, which indicated that the homemade ELCAD-AES system has a good performance. Finally, practical water samples such as tap water, boiled tap water, ground water, boiled ground water and lake water were analyzed by the method. The results were in agreement with those by the EDTA titration. This demonstrates that ELCAD-AES has the capacity for on-line determination of water hardness.

Radiotherapy uses high-energy X-rays or other particles to destroy cancer cells and medical practitioners have used this approach extensively for cancer treatment (Hachadorian et al., 2020). However, it is accompanied by risks because it seriously harms normal cells while killing cancer cells. The side effects can lower cancer patients' quality of life and are very unpredictable due to individual differences (Bentzen, 2006). Therefore, it is essential to assess a patient's body damage after radiotherapy to formulate an individualized recovery treatment plan. Exhaled volatile organic compounds (VOCs) can be changed by radiotherapy and thus used for medical diagnosis (Vaks et al., 2012). During treatment, high-energy X-rays can induce apoptosis; meanwhile, cell membranes are damaged due to lipid peroxidation, converting unsaturated fatty acids into volatile metabolites (Losada-Barreiro and Bravo-Díaz, 2017). At the same time, radiotherapy oxidizes water, resulting in reactive oxygen species (ROS) that can increase the epithelial permeability of pulmonary alveoli, enabling the respiratory system to exhale volatile metabolites (Davidovich et al., 2013; Popa et al., 2020). These exhaled VOCs can be used to monitor body damage caused by radiotherapy.
Breath Tests/methods* ; Exhalation ; Humans ; Quality of Life ; Respiratory System/chemistry* ; Volatile Organic Compounds/analysis*