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A natural resource such as peony flower has been employed for the first time as a new carbon precursor to prepare green-emitting carbon nanodots (CDs).

Series of biodegradable polyesters poly(butylene adipate) (PBA), poly(butylene succinate) (PBS), and poly(butylene adipate-co-butylene terephthalate) (PBAT) were synthesized successfully by melt polycondensation. The polyesters were characterized by Fourier transform infrared spectroscopy (FTIR),1H-NMR, differential scanning calorimetry (DSC), and gel permeation chromatography (GPC), respectively. The blends of poly(lactic acid) (PLA) and biodegradable polyester were prepared using a twin screw extruder. PBAT, PBS, or PBA can be homogenously dispersed in PLA matrix at a low content (5–20 wt%), yielding the blends with much higher elongation at break than homo-PLA. DSC analysis shows that the isothermal and nonisothermal crystallizabilities of PLA component are promoted in the presence of a small amount of PBAT.

SnO2 has been considered as a promising anode material for lithium‐ion batteries (LIBs) and sodium ion batteries (SIBs), but challenging as well for the low‐reversible conversion reaction and coulombic efficiency. To address these issues, herein, SnO2 quantum dots (≈5 nm) embedded in porous N‐doped carbon matrix (SnO2/NC) are developed via a hydrothermal step combined with a self‐polymerization process at room temperature. The ultrasmall size in quantum dots can greatly shorten the ion diffusion distance and lower the internal strain, improving the conversion reaction efficiency and coulombic efficiency. The rich mesopores/micropores and highly conductive N‐doped carbon matrix can further enhance the overall conductivity and buffer effect of the composite. As a result, the optimized SnO2/NC‐2 composite for LIBs exhibits a high coulombic efficiency of 72.9%, a high discharge capacity of 1255.2 mAh g−1 at 0.1 A g−1 after 100 cycles and a long life‐span with a capacity of 753 mAh g−1 after 1500 cycles at 1 A g−1. The SnO2/NC‐2 composite also displays excellent performance for SIBs, delivering a superior discharge capacity of 212.6 mAh g−1 at 1 A g−1 after 3000 cycles. These excellent results can be of visible significance for the size effect of the uniform quantum dots.

The severe polarization triggered by the limited electrochemical activity of carbon dioxide as well as the insulating and insoluble discharge product Li2CO3 significantly impedes the practical application of Li-CO2 batteries....

Hierarchical Co 3 O 4 porous nanowires (NWs) have been synthesized using a hydrothermal method followed by calcination. When employed as a cathode catalyst in non-aqueous Li-oxygen batteries, the Co 3 O 4 NWs effectively improve both the round-trip efficiency and cycling stability, which can be attributed to the high catalytic activities of Co 3 O 4 NWs for the oxygen reduction reaction and the oxygen evolution reaction during discharge and charge processes, respectively.

Aromatic heterocyclic polyimides are used extensively in industries for their excellent mechanical properties, high glass transition temperatures (Tg), and so on. A quantitative structure–property relationship (QSPR) model was developed to predict the Tg values with 54 aromatic heterocyclic polyimides by using an artificial neural network (ANN) back‐propagation algorithm. Fifty‐four aromatic heterocyclic polyimides were randomly divided into a training set (36) and a test set (18). Three molecular descriptors (the connectivity index X1A, the topological descriptor PW3, and the 3D‐MoRSE descriptor Mor09e) were selected to produce the mode. Simulated with the final optimum ANN model with 3‐3‐1 structure, the results show that the predicted Tg values are in good agreement with the experimental ones, with the root mean square errors (RMSEs) of 12.4 K (R = 0.935) and 16.4 K (R = 0.937) for the training set and the test set, respectively. POLYM. ENG. SCI., 50:1547–1557, 2010. © 2010 Society of Plastics Engineers