in solid calcination of a mixt. of metal nitrates at 350°C; powder X-ray diffraction;

in melt CoO (1mol) and Cr2O3 (1mol) heated in the fluxing agent KCl to 1000-1500°C;; excessive CoO extracted from the powdered compound with concd. HCl or HNO3;;

co-polymer of styrene-co-maleic acid anhydride in water; N,N-dimethyl-formamide byproducts: NaCl; addn. of CoCl2*6H2O, CrCl3*6H2O to soln. of copolymer styrene-maleic acid anhydride in DMF; stirring at 353 K for 2 h; dropping into H2O; dropping of aq. NaOH, pptn., filtration, washing (H2O); drying in vac. at 323 K for 72 h; annealing at 773 K for 3h; repeated washing by aq. soln. of acid and alkali for 6 times;

in not given a soln. of CoCl2 and KCr(SO4)2*12H2O pptd. with soda; resulting ppt. is calcinated;;

in not given a soln. of CoSO4 and Cr2(SO4)3 pptd. with soda; resulting ppt. is calcinated;;

in neat (no solvent) formation on heating a pulverized mixture of CoCl2 and K2Cr2O7 to 900°C for one hour;; the porduct is treated with water and concd. HCl, washed and dried; use as a catalyst;;

in neat (no solvent, solid phase) from stoich. amts. of Cr2O3, Co3O4 and V2O5 by a solid-state react.; annealing at 670°C (60 h), 750°C (60 h); quenching to room temp.; XRD studies;

powder mixt. (molar ratio 1:1) pelletizing, heating in air at 1100-1300°C for 72 h;