RESUMEN
LiFePO4/carbon-network composite was synthesized by a high temperature solid-state method using the natural sawdust as carbon precursor. The microstructure of the as-synthesized sample was characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), respectively. The results revealed that the LiFePO4 particles with diameters ranging from 30 to 150 nm were well connected by carbon networks. The electrochemical performance of the composite was characterized using galvanostatic charge-discharge technique. The initial discharge capacity of LiFePO4/carbon-network cathode reached 126 mAh x g(-1) with 0.2 C rate.
RESUMEN
We isolated and sequenced a cDNA clone corresponding to the 2.5 kb storage protein (SP-1) from fall webworm, Hyphantria cunea. The SP-1 gene encoded a pre-protein of 753 amino acids, including a signal peptide of 15 amino acids. The deduced amino acid sequence of SP-1 contained one potential N-glycosylation site, and the calculated isoelectric point and molecular weight of secreted SP-1 were pI = 8.38 and 86.8 kDa, respectively. A Northern blot of mRNA from various developmental stages revealed that the SP-1 mRNA in fat body appears in early last instar larvae and accumulates to a maximum level at the end of last instar larvae. The persistence of SP-1 transcript through the early pupal stage suggests that its mRNA might be stable or expressed during the pupal stage. SP-1 transcription was also found in the ovary as well as testis. This local expression of SP-1 in both reproductive organs seems to allow the insect to keep its reproductive activity under a nutritional stress.