A hollow sphere secondary structure of LiFePO4 nanoparticles

We report on the evolution of a hollow sphere secondary structure of spherical nanoparticles by a solubilization-reprecipitation mechanism based on the difference of solubility products (K-sp) of two different precipitates. Carbon-coated nanoparticles of olivine structure LiFePO4 served as the primary nano-blocks to build the secondary nano-architecture.close656

Catalytic carbonization of an uncarbonizable precursor by transition metals in olivine cathode materials of lithium ion batteries

Herein, we report on catalytic effects of transition metals (Me) in phospho-olivines (LiMePO4) on carbonization of cetyltrimethylammonium bromide (CTAB). Carbon coating is the required process to enhance electronic conductivity of phospho-olivines that are used as cathode materials for lithium ion batteries. Primary particles of phospho-olivines were in situ coated with CTAB and the adsorbed carbon precursor was carbonized to provide an electrically conductive pathway. CTAB was successfully carbonized in a significant amount with Fe in phospho-olivines (LiFexMn1-xPO4 with x = 1 and 0.5) even if CTAB is thermally decomposed around 300 degrees C without any residual mass in the absence of the phospho-olivines. LiMnPO4 was the most inferior in terms of CTAB adsorption and thermal carbonization. LiNiPO4 and LiCoPO4 showed inefficient conversion of adsorbed CTAB to carbon even if their adsorption ability for CTAB is quite large. Also, the effect of the amount of carbon coating on LiFePO4 was investigated, leading to a conclusion that the carbon thickness balanced between electronic and ionic conductances results in the best electrochemical performances of lithium ion batteries specifically at high discharge rates.close1

Efficacy and Safety of Human Placental Extract Solution on Fatigue: A Double-Blind, Randomized, Placebo-Controlled Study

Introduction. Fatigue is a common symptom, but only a few effective treatments are available. This study was conducted to assess the efficacy and safety of the human placental extract solution, which has been known to have a fatigue recovery effect. Methods. A total of 315 subjects were randomly assigned to three groups: group 1 (with Unicenta solution administration), group 2 (with exclusively human placental extract administration, excluding other ingredients from the Unicenta solution), and the placebo group. Subsequently, solutions were administered for four weeks. Results. The fatigue recovery rate was 71.00% in group 1, 71.72% in group 2, and 44.21% in the placebo group, which show statistically significant differences between the group 1 and the placebo group (P value = 0.0002), and between group 2 and the placebo group (P value = 0.0001). Conclusion. The human placental extract solution was effective in the improvement of fatigue