Abstract. Polycaprolactone (PCL)/calcium sulfate (CS) whisker composites have been fabricated by melt blending and coprecipitation methods respectively. Scanning electron microscope (SEM) was used to observe the microstructure of the composites. The crystallization and thermal properties were characterized by polarized optical microscope (POM), X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). For composites prepared by melt blending method, experiment results show that average length of the whiskers is shortened. The crystallization perfection of PCL in composites is improved by adding whiskers. The flexural strength increases whereas the impact strength decreases. For composites prepared by coprecipitation method, whisker addition worsens the crystallization perfection of PCL. An improvement of 21% in flexural strength and 22% in impact strength has been achieved for the composite with 15 wt% of whiskers.

Summary Based on the five wild Chinese sturgeons which were captured from the Yichang section of the Yangtze River, and the 323 offsprings of the Chinese sturgeons, were studied as to their survival, development and behaviour under aquarium conditions between 2005 and 2007 in the captive environment of an aquarium. All five wild caught females survived, with weight gains ranging from 0.55% (Specimen W1#: Onset: 320.00 kg, Final: 336.00 kg; across 27 months) to 10.00% of original body weight (Specimen W32#: Onset: 125.00 kg, Final: 175.00 kg; across 4 months). In addition, the gonads of one captured fish redeveloped to stage IV by August 2007. The changes of the depth in the tank were observed before, during and after active food intake. Furthermore, the fish formed strong feeding associations with live food items, such as Hypophthalmichthys molitrix, Cyprinus carpio, and Paralichthys lethostigma, while rarely feeding on Hexagrammos otakii and Epinephelus awoara, occasionally on Monopterus albus, Penaeus vannamei, Leiocassis longirostris, and never on Eriocheir sinensis H. Milne‐Edwards, Misgurnus anguillicaudatus, Silurus asotus Linnaeus, Octopus variabilis, Anadara uropygimelana. The development of food preferences in the captive environment suggest that these Chinese sturgeon successfully acclimated to the large aquarium, in addition, the survival rate of the filial generation offspring was 86%. Across the study period, for the older captive bred offspring (1997 and 2001 stocks) minimum weight increase per month was 4.28% (F1‐2001: Onset: 12.24 ± 1.11 kg, Final: 25.35 ± 2.10 kg; over 25 months) and the minimum lengthwise growth rate per month was 1.39% (F1‐1997: Onset: 187.32 ± 1.32 cm, Final: 260.00 cm; across 28 months). However, the youngest sturgeon (the 2005 offspring), had the highest weight gain of 29.35% per month (Onset: 16.50 ± 1.92 kg, Final: 8733.33 ± 739.80 kg; across 18 months) and lengthwise growth rate 35.70% per month (Onset: 15.53 ± 0.77 cm, Final: 115.33 ± 4.14 cm; across 18 months) respectively.