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Abstract In this work, we investigate the form factors of $$B_c$$ B c decays into $$J/\Psi , \psi (2S,3S),\eta _c,$$ J / Ψ , ψ ( 2 S , 3 S ) , η c , $$ \eta _c(2\,S,3\,S), \chi _{c0}, \chi _{c1}, h_c$$ η c ( 2 S , 3 S ) , χ c 0 , χ c 1 , h c , and X(3872) mesons in the covariant light-front quark model (CLFQM). For the purpose of the branching ratio calculation, the form factors of $$B_c\rightarrow D^{(*)}, D^{(*)}_s$$ B c → D ( ∗ ) , D s ( ∗ ) transitions are also included. In order to obtain the form factors for the physical transition processes, we need to extend these form factors from the space-like region to the time-like region. The $$q^2$$ q 2 dependence for each transition form factor is also plotted. Then, using the factorization method, we calculate the branching ratios of 80 $$B_c$$ B c decay channels with a charmonium involved in each mode. Most of our predictions are comparable to the results given by other approaches. As to the decays with the radially excited-state S-wave charmonia involved, such as $$\psi (2S,3S)$$ ψ ( 2 S , 3 S ) and $$\eta _c(2S,3S)$$ η c ( 2 S , 3 S ) , two sets of parameters for their light-front wave functions, corresponding to scenario I (SI) and scenario II (SII), are adopted to calculate the branching ratios. By comparing with the future experimental data, one can discriminate which parameters are more favored.

We successfully employed bisphenol A and several different formyl-containing monomers as useful building blocks to construct a series of hydroxy-group-containing porous organic polymers in a sealed tube at high temperature. Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy are utilized to characterize the possible structure of the obtained polymers. The highest Brunauer–Emmet–Teller specific surface area of the phenolic-resin porous organic polymers (PPOPs) is estimated to be 920 m2 g–1. The PPOPs exhibit a highest carbon dioxide uptake (up to 15.0 wt % (273 K) and 8.8 wt % (298 K) at 1.0 bar), and possess moderate hydrogen storage capacities ranging from 1.28 to 1.04 wt % (77 K) at 1.0 bar. Moreover, the highest uptake of methane for the PPOPs is measured as 4.3 wt % (273 K) at 1.0 bar.

We demonstrated the synthesis of five kinds of microporous organic polymers based on aldol self-condensation of di- and multiacetyl-containing building blocks catalyzed by thionyl chloride. The α,β-unsaturated ketone (dimerization) and 1,3,5-trisubstituted benzene (cyclotrimerization) can be observed in the resulting polymers by Fourier transform infrared and solid-state 13C CP/MAS NMR spectroscopy. The regular spheres and nanometer-scaled cavities were also seen from scanning electron microscopy and high-resolution transmission electron microscopy images. The highest Brunauer–Emmet–Teller specific surface area up to 832 m2g–1was obtained for the resulting polymers with a pore volume of 0.48 cm3g–1. The polymers show great hydrogen storage capacities (up to 1.56 wt %) at 77 K and 1 bar. These excellent characteristics would make them become promising candidates for heterogeneous catalysis, separation, and gas storage. [ABSTRACT FROM AUTHOR]