Research On Joint Toxicity Of Multivariant Heavy Metal Based On The Fractional Factorial

In order to research five heavy metal lead, chromium, cobalt, nickel and copper on joint toxicity to photobacterium phosphoreum in coexist with potassium, calcium, magnesium, oxalic acid and tartaric acid the resolution of V fractional factorial experiment was used, combined with multivariate linear regression and the best subset regression to establish regression model of photobacterium phosphoreum light inhibition ratio. The result shows that significant influence factor of the main effect were respectively Chromium, copper, nickel, potassium, oxalate acid, magnesium, tartaric acid, calcium. Three kinds of metal potassium, magnesium and calcium can reduce system toxicity, three kinds of heavy metals chromium, copper and nickel showed biggest toxicity to system. The significant antagonism effect of second-order interaction in the system was potassium*calcium, potassium* oxalic acid, calcium*magnesium, calcium*tartaric acid, magnesium*lead, magnesium*cobalt, magnesium*nickel, oxalic acid*cobalt, tartaric acid*lead, lead*chromium, lead*copper, chromium*nickel, cobalt*copper. The significant synergy effect of second-order interaction in the system was potassium*tartaric acid, calcium*nickel, calcium*copper, magnesium*oxalic acid, magnesium*chromium, oxalic acid*chromium, Iead*nickel, chromium*cobalt.This research had established quantitative ion characteristic parameters-activity relation model between heavy metal ion characteristic parameters and toxic effect of heavy metals. This research selected 15 kinds of heavy metal ion characteristic parameters to study the correlation analysis. Six kinds of characteristic parameters AIP (eV),|logKOH|, Z2/r, σp, OX, IP were significant correlation with toxic effect. Four kinds of characteristic parameters △IP (eV), Z2/r, OX, IP has a positive correlation with toxic effect,|logIOH| and σp has a negative correlation with toxic effect. Use 6 kinds of significant correlation characteristic parameters establish the QICAR model. Principal component analysis was carried out on 6 kinds of characteristic parameters. Establish the QICAR model of toxic effect with the new principal component factors. Afterwards replace principal component factors by characteristic parameters, as we can see in the model|logKOH|, IP, △IP (eV), OX, Z2/r had positive Coefficient, σp had negative coefficient.In order to research variation range of photobacterium phosphoreum light inhibition ratio, this study chosen copper as the object, established binary model which independent variable were concentration of copper and respectively concentration of potassium, calcium, magnesium, oxalic acid and tartaric acid. The result showed that potassium can decrease the light inhibition ratio from 46.10 percent to 13.69 percent; calcium can decrease the light inhibition ratio from 37.14 percent to 13.69 percent; magnesium can decrease the light inhibition ratio from 54.88 percent to 13.69 percent; the range of decrease were respectively 32.41 percent,23.45 percent and 41.19 percent. Oxalic acid can increase the light inhibition ratio from 5.04 percent to 25.65 percent; tartaric acid can increase the light inhibition ratio from 10.40 percent to 25.65 percent; the range of increase was respectively 20.61 percent,15.25 percent.