Modeling Electrified Pt(111)-Had/Water Interfaces from Ab Initio Molecular Dynamics.

Unraveling the atomistic structures of electric double layers (EDL) at electrified interfaces is of paramount importance for understanding the mechanisms of electrocatalytic reactions and rationally designing electrode materials with better performance. Despite numerous efforts dedicated in the past, a molecular level understanding of the EDL is still lacking. Combining the state-of-the-art ab initio molecular dynamics (AIMD) and recently developed computational standard hydrogen electrode (cSHE) method, it is possible to realistically simulate the EDL under well-defined electrochemical conditions. In this work, we report extensive AIMD calculation of the electrified Pt(111)-Had/water interfaces at the saturation coverage of adsorbed hydrogen (Had) corresponding to the typical hydrogen evolution reaction conditions. We calculate the electrode potentials of a series of EDL models with various surface charge densities using the cSHE method and further obtain the Helmholtz capacitance that agrees with experiment. Furthermore, the AIMD simulations allow for detailed structural analyses of the electrified interfaces, such as the distribution of adsorbate Had and the structures of interface water and counterions, which can in turn explain the computed dielectric property of interface water. Our calculation provides valuable molecular insight into the electrified interfaces and a solid basis for understanding a variety of electrochemical processes occurring inside the EDL.

[Effect of Busheng Huoxue Capsule on the quality of life of primary osteoporosis senile males].

OBJECTIVE: To investigate the effect of Busheng Huoxue Capsule (BHC) on the quality of life (QOL) in senile male osteoporosis (OP) patients, and to explore its mechanisms. METHODS: Totally 200 senile primary OP patients were randomly assigned to two groups according to random digit table method, 100 in each group. Patients in the treatment group took BHC plus caltrate-D (600 mg CaCO3), while those in the control group took alendronate (70 mg per week) plus caltrate-D. The therapeutic course was 12 months for all. Chinese medical symptom score and quality of life (QUALEFFO-41) score, bone mineral density (BMD) of lumbar vertebra (L2 -L4) and left femoral neck were compared between the two groups before and after treatment. Serum free testosterone (FT) and estradiol (E2) were also measured. RESULTS: Chinese medical symptom scores and QUALEFFO-41 scores, serum FT and E2 levels increased in the two groups after treatment (P < 0.05, P < 0.01). The therapeutic effect was superior in the treatment group (P < 0.05, P < 0.01). After treatment the BMD of lumbar vertebra (L2 -L4) and the left femoral neck were somewhat improved (P < 0.05), but with no statistical difference between the two groups (P > 0.05). CONCLUSION: BHC could effectively improve the QOL of senile male OP patients, which might be correlated with elevating the BMD levels and regulating the levels of sex hormones.