Highly efficient blue phosphorescent organic light-emitting diode (OLED) is achieved by using a blend of biphenyl (spiro[fluorene-9,9'-xanthen]-2-yl) phosphine oxide (SFX2PO) and various of hole- or electron-transporting materials such as di-[4-(N,N-di-p-tolyl-amino)-phenyl]cyclohexane (TAPC), 2,2',2"-(1,3,5-benzinetriyl)-tris(1- phenyl-1-H-benzimidazole) (TPBi) and 4,4',4"-tris(carbazol-9-yl)triphenylamine (TCTA). The results show that TCTA and SFX2PO can partially form exciplex and have better charge carrier balance performance. The driving voltage and efficiency are improved in a multi-player device with TCTA and SFX2PO as the co-host. The device shows a maximum current efficiency of 22.75 cd•A^–1, which is nearly two folds over the device using SFX2PO or phosphine oxide spirobifluorene derivative (SPPO1) as a single host.

The high strain cyclopropane as σ block model inserted in organic semiconductors to tune the structures and optical properties was investigated by the density functional theory method. The band gaps and absorption peaks of 1,2-disubstituted cyclopropanes were between the corresponding alkanes and olefins. The cis-isomers had higher steric strain between two substituents and lower symmetry than the trans-isomers in ground-state structures. The electronic transitions (S₀→S₁) were mainly on the aryl parts, which were stronger coherence with surrounding atoms in cis-isomers, while the trans-isomers were on the cyclopropyl. Furthermore, 1,2-disubstituted cyclopropanes (1A, 1B, 2A, 4B) could respond to the charge stimulation, which are potential materials for organic electronics and mechatronics.

A new tirucallane-type triterpenoid, swietentol (1), was isolated from the barks of Swietenia macrophylla, toether with four known triterpenoids (2—5), five known limonoids (6—10), and other six compounds (11—16). The structure of swietentol (1) was elucidated by extenstive 2D NMR and MS analysis.

Some characteristics of ¹H-¹⁵N heteronuclear multiple bond correlation (HMBC) spectroscopy of an aliphatic amine was described. A measuring method of ¹H-¹⁵N HMBC spectroscopy at natural abundance was also introduced. ¹H-¹⁵N HMBC spectra can be recorded using the Bruker standard experiment HMBCGP_¹⁵N. The optimal value of the acquisition parameter CNST13 for this experiment ranges from 3 to 5. The measuring time is about 4 times longer than the ¹H-¹³C HMBC one.