New Insight into the Electronic Effect for Cu Porphyrin Catalysts in Electrocatalytic of CO2 into CH4.

Perturbation of the copper (Cu) active site by electron manipulation is a crucial factor in determining the activity and selectivity of electrochemical carbon dioxide (CO2 ) reduction reaction (e-CO2 RR) in Cu-based molecular catalysts. However, much ambiguity is present concerning their electronic structure-function relationships. Here, three molecular Cu-based porphyrin catalysts with different electron densities at the Cu active site, Cu tetrakis(4-methoxyphenyl)porphyrin (Cu─T(OMe)PP), Cu tetraphenylporphyrin (Cu─THPP), and Cu tetrakis(4-bromophenyl)porphyrin (Cu─TBrPP), are prepared. Although all three catalysts exhibit e-CO2 RR activity and the same reaction pathway, their performance is significantly affected by the electronic structure of the Cu site. Theoretical and experimental investigations verify that the conjugated effect of ─OCH3 and ─Br groups lowers the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbitals (LUMO) gap of Cu─T(OMe)PP and Cu─TBrPP, promoting faster electron transfer between Cu and CO2 , thereby improving their e-CO2 RR activity. Moreover, the high inductive effect of ─Br group reduces the electron density of Cu active site of Cu─TBrPP, facilitating the hydrolysis of the bound H2 O and thus creating a preferable local microenvironment, further enhancing the catalytic performance. This work provides new insights into the relationships between the substituent group characteristics with e-CO2 RR performance and is highly instructive for the design of efficient Cu-based e-CO2 RR electrocatalysts.

Construction of Synergistic Ni3 S2 -MoS2 Nanoheterojunctions on Ni Foam as Bifunctional Electrocatalyst for Hydrogen Evolution Integrated with Biomass Valorization.

The intrinsic sluggish kinetics of the oxygen evolution reaction (OER) limit the improvement of hydrogen evolution reaction (HER) performance, and substituting the anodic oxidation of biomass materials is an alternative approach, given its lower oxidation potential and higher added value compared to those of OER. In this study, a Ni3 S2 -MoS2 nanoheterojunction catalyst with strong electronic interactions is prepared. It exhibits high efficiency for both the HER and the electrooxidation of 5-hydroxymethylfurfural (HMF). In a two-electrode cell with Ni3 S2 -MoS2 serving as both the anode and cathode, the potential is only 1.44 V at a current density of 10 mA cm-2 , which is much lower than that of pure water splitting. Density functional theory calculations confirm that the strong chemisorption of H and HMF at the interface leads to outstanding electrocatalytic activity. The findings not only provide a strategy for developing efficient electrocatalysts, but also provide an approach for the continuous production of high value-added products and H2 .

Performance analysis of the BDSBAS-B1C message in trial operation stage.

BeiDou Satellite-based Augmentation System (BDSBAS) has come into the trial operation stage since July, 2020. To evaluate the characteristic of the augmentation message in BDSBAS-B1C signal, the effectiveness of the message content was firstly analyzed, and then the validity of the broadcasting strategy was estimated. Finally, the accuracy of the user equivalent ranging error (UERE) and the single frequency positioning error with different correction parameters in BDSBAS-B1C message was evaluated. Based on the above analysis, the effectiveness of the augmentation message was preliminarily verified with the results showing that: (1) the BDSBAS-B1C message type, information content and update interval have basically met the international standard; (2) the accuracy of the UERE obtained with the augmentation message had an obvious improvement in contrast to that of the UERE obtained with the usual navigation message of the GPS satellites, and the ionospheric delay was one of the important factors which affected the accuracy of the UERE; (3) the positioning accuracy obtained with the augmentation message was also improved, and the improvement was more obvious in the service areas with high availability of the ionospheric parameters.

Water-assisted one-pot synthesis of N-doped carbon supported Ru catalysts for heterogeneous catalysis.

For the first time, a simple yet efficient water-assisted one-pot pyrolysis (WAOP) strategy was developed to in situ liberate the inaccessible Ru active sites confined inside N-doped carbon. The liberated Ru/CN catalysts exhibit a 9-fold improvement in catalytic activity for quinoline hydrogenation compared with catalysts obtained from the water-free pyrolysis process, and high tolerance for selective hydrogenation of various quinolines substituted with different functional groups. We anticipate that WAOP addresses a key issue that currently plagues carbon-based catalyst synthesis and should lead to improvements in fields as diverse as chemical production and environmental protection.

Reproductive traits of polycystic ovary syndrome in female rhesus monkeys.

The objective of this study was to set up a rhesus monkey model of polycystic ovary syndrome (PCOS), which is globally prevalent among reproductive-aged human women, and to understand the reproductive traits of PCOS female monkeys. Six adult female rhesus monkeys aged 6-10 a, were divided into a PCOS group and a control group. The PCOS group were given two cycles of subcutaneous injections of propionic acid testosterone (PAT), 3.5 mg/kg body weight, on day 1, day 3, and day 5 of the menstrual cycle, respectively, and then given muscle injections of human chorionic gonadotropin (HCG), 350 IU/kg body weight, on day 7, day 9, and day 11, respectively. Results showed that high levels of serum LH and T [(5.35±0.17) IU/L and (7.58±0.14) ng/mL, respectively], and a high ratio value of LH/FSH (5.35/1.30=4.12) were observed in the PCOS group. No significant differences were found in serum FSH, E2, and P in the PCOS group compared with those of the control. Polycystic ovaries in the PCOS monkeys were recorded by live ultrasound. The blastocysts rates of the PCOS vs. the control were 23.53% vs. 66.67%, and there was a significant difference between the two groups. This study shows that PAT coupled with HCG can induce PCOS in rhesus monkeys in the short term. The reproductive features of PCOS monkeys were similar to those of PCOS patients.