Searching for distinctive signatures, which characterize different formation channels of
binary black holes (BBHs), is a crucial step towards the interpretation of current and future
gravitational wave detections. Here, we investigate the demography of merging BBHs in
young star clusters (SCs), which are the nursery of massive stars. We performed 4� 103 N-
body simulations of SCs with metallicity Z= 0.002, initial binary fraction 0.4, and fractal initial
conditions, to mimic the clumpiness of star-forming regions. Our simulations include a novel�…

Spinel-type mixed transition metal oxides CoCuMoO x nanoparticles were synthesized
through a modified sacrificial template method, by utilizing mashed carbon microspheres as
templates. Compared with the direct calcination of mixture precursor, we obtained well-
crystallized CoCuMnO x sample with high purity and sizes of 5–20 nm. Mixed valence states
of transition metal elements are revealed by X-ray photoelectron spectroscopy, which is a
desirable feature for oxygen reduction reaction (ORR) catalyst. Moreover, we further�…