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The forecasting precision of GM(1,1) is very low, when the data sequence is not smooth. The logarithm smoothing is used for the original data sequence. Considering the low precision caused by overlarge and forecasting gray interval for gray modeling, A novel method is proposed for power load forecasting: weighted forecasting method of gray related degree with revised parameter and logarithm smoothing. The method can make various factors weaken or counteracted and prevent the forecasting data from too fast increasing. The proposed model is demonstrated by a test in a certain area. The result shows that the method is effective both in theory and in practice.

Polyacrylamide (PAM) was usually atoxic, stable. Its hydrogel (PAMG) has been used in plastic and aesthetic surgery more than 10 years in P.R.China, Ukraine and Russia. But there were some complications with PAMG injected in patients. Considering the complicacy in vivo, it was necessary to study the PAMG’s stability. In this paper, H2O2 was added in PAMG in vitro and acrylamide (AM) content after oxidating was determined using HPLC method. Detection limit for AM can be achieved in the parts-per-billion rang. The AM content in supernatant at 0.5, 1,2 and 3 hr after oxidating of PAMG was 1.27e-8g/ml, 1.35e-8g/ml, 1.03e-7g/ml and 2.74e-7g/ml, respectively. The AM content in supernatant of PAMG was 7.70e-9g/ml. These results indicated that PAMG can be degraded to AM by hydroxyl radical. Under the same condition, the AM content was stable. So, AM can exist for a while when it was produce by degrading of PAMG. That can increase the toxicity of PAMG.