The composition and operation conditfons are: sodium nitrate 60-150g/L or nitric acid(d=1.42) 50g/L, sulfuric acid(d=1.84) 350-450mL/L, surfactant'855, 30-60mL/L, temperature 10-70℃, duration 30-60 sec.
The results showed that in the presence of sodium nitrate at pH 4.0, Hg(Ⅱ) could be floated by potassium iodide-cetylpyridine chloride-water system, and Zn(Ⅱ), Ni(Ⅱ), Co(Ⅱ), Mn(Ⅱ), Fe(Ⅱ), Al(Ⅲ) could not be floated.
The results of multi-factor-and-multi-level experiments showed that the concentration changing of glucose,sodium nitrate and pH affected the carotenoids yield remarkably and the sample of A3B3C1 containing 3 g/L of glucose and 1.5 g/L of sodium nitrate,pH 6.0 was the best among all samples,and its output of carotenoids reached 2.318 mg/g.
(1)Nitration:At n (sulfuric acid)∶ n (sodium nitrate)∶ n (isophthalic acid)=7.9∶2 2∶1 0(at 60℃)for 3h,the yield of nitrate is 86 1%,(2)Reduction:At n (iron)∶ n (nitrate)=3.0∶1 0 after being refluxing for 3 h,the yield of aminate is 77 2%;
The 1∶1 mixture of activated carbon and chitosan can restrain the nitrite formation in 10 mg/L sodium nitrate solution to keep the concentration of nitritenitrogen below 0006 mg/L.
The best alkali chemical polishing solution for aluminum and its technological conditions are as follows. 300 g/L sodium hydroxide, 250 g/L sodium nitrate, 20 g/L thiourea, 10 g/L sodium silicate, 1.5~1.8 g/L sodium lauryl sulfate, at 60~70 ℃, polishing time 80~100 s.
The sol coagulation thresholds are determined in the presence of sodium nitrate and sulfate, as well as of mixed magnesium salt at various pH values of the dispersion medium.
New nanocomposites based on zeolites (NaA-NaNO2, NaA-NaNO3) and opals (o-NaNO2, o-NaNO3) that contain sodium nitrite or sodium nitrate nanoparticles in cages of regular porous matrices are prepared.
The half wave potential of the lead ion was determinted at 25℃ in sodium perchlo-rate-sodium nitrate mixtures over the range 0-2.0 M sodium nitrate at an ionic strength of 3.00. From the data, the existence of Pb (NO_3)_2, Pb(NO_3)_3, in addition to the species.PbNO_3~+ and Pb~(++) as found by previous investigators was revealed. The consecutive stability constants were found to be: K_1=2.34±0.02, K_2=1.30±0.03, K_3 = 3.25±0.12.
The half wave potential of the cadmium ion was determined at 25 C in sodium perchlorate-sodium nitrate mixtures over the range of 0-2.2 M nitrate at an ionic strength of 3.00. The treatment of the data revealed the existence of Cd~(++), Cd(NO_3)~+ and Cd(NO_3)_2. The successive stability constants were found to be K_1 = 0.62±0.02 and K_2=0.16±0.02, while the errors in the difference between the half wave potentials of the simple and complex ions were estimated to be less than ±0.2 mv...
The complex compound formation of cupric ion with ethylene diamine was studied polarographically in sodium perchlorate (or sodium nitrate) solutions of ionic strength equal to 0.1M (or 1M). It was found that when the concentration of cupric ion is 1×10~(-3)M and that of ethylene diamine is over 0.6M, Cu~(Ⅱ) trisethylene diamine is the predominent species thatexists in solution, and when the concentration of ethylene diamine is below 0.6M Cu~Ⅱ-bis ethylene diamine is the main complex that e...