A technique of treating steel with rare earth fluoride complex additives(REFCA),effects and influnce factors have been studied.REFCA play a role on controlling inclusion morphology,purifying the molten steel and impro...A technique of treating steel with rare earth fluoride complex additives(REFCA),effects and influnce factors have been studied.REFCA play a role on controlling inclusion morphology,purifying the molten steel and improving properties of steel.The optimum composition of REFCA is REF_3 42%;CaO 33%;SiCa 25%,and the amount of REF_3 is 0.5 wt%～0.6 wt% of steel.展开更多
Dibenzoyl peroxide undergoes oxidative addition on metallic copper powder with 2,2′-bipyridine(or imidazole)in a mixed solvent(methanol and tetrahydrofuran),and affords the Cu(Ⅱ)complexes-[Cu(Ce(C_6H_5COO)_2(2,2'...Dibenzoyl peroxide undergoes oxidative addition on metallic copper powder with 2,2′-bipyridine(or imidazole)in a mixed solvent(methanol and tetrahydrofuran),and affords the Cu(Ⅱ)complexes-[Cu(Ce(C_6H_5COO)_2(2,2'-bipy)]H_2O(1) and[Cu(C_6H_5COO)_2(C_3H_4N_2)_2](2).The structure was solved by direct methods and Fourier synthesis.C_(24)H_(20)N_2O_5Cu (1),Mr=479.78,space group P2(1)/c,a=6.986(7), b=18.833(I),c=17.021(3),α=γ=90°,Z=4,V=2218.1~3,Dc=1.443g/cm\+3,R=0.055 Rw=0.062.Complex(2),C_(20)H_(18)N_4O_4Cu(2),Mr=441.74,space group P2(1)/n,a=8.699(4), b=9.840(6),c=12.399(5),α=γ=90°,β=100.8°,Z=4,V=1010.9~3,Dc=1.654g/cm\+3,R=0.055, Rw=0.062.展开更多
Yttria stabilized zirconia (YSZ) is a kind of electrolyte materials widely used for solid oxide fuel cell (SOFC). Some rare earth elements (Dy 3+, Yb 3+, Sc 3+, etc), which have similar radii to Zr 4+, can dissolve in...Yttria stabilized zirconia (YSZ) is a kind of electrolyte materials widely used for solid oxide fuel cell (SOFC). Some rare earth elements (Dy 3+, Yb 3+, Sc 3+, etc), which have similar radii to Zr 4+, can dissolve into ZrO_2, and result in oxygen vacancy and crystal lattice distortion, so enhance its conductivity and lower the activation energy. YSZ electrolyte doped with Sc 3+(Dy 3+) and Yb 3+ were prepared by combustion synthesis. The conductivity is enhanced due to the distortions of crystal lattice and the increase in oxygen transfer passage radii, reaching 0.15 S·cm -1 at 1000 ℃. Crystalline symmetry of ZrO_2 changed from monoclinic to tetragonal, and then to cubic, with the elevation of calcining temperature. SEM photographs show the complex additives promoted growth of ZrO_2. There are some second phases along the grain boundaries, which restricted the further increase of conductivity. The addition of Al 3+ or Ca 2+ improve grain boundary, but lower the high-temperature conductivity.展开更多
Piglets’ alactation stress with diarrhea as a main symptom is a serious problem in pig farming. The experiment indicates that the complex premix additive Huzikang duannaibao can be used to control ablactation stress ...Piglets’ alactation stress with diarrhea as a main symptom is a serious problem in pig farming. The experiment indicates that the complex premix additive Huzikang duannaibao can be used to control ablactation stress syndromes and its effects are better than that of the common antibiotic ligomycin.展开更多
文摘A technique of treating steel with rare earth fluoride complex additives(REFCA),effects and influnce factors have been studied.REFCA play a role on controlling inclusion morphology,purifying the molten steel and improving properties of steel.The optimum composition of REFCA is REF_3 42%;CaO 33%;SiCa 25%,and the amount of REF_3 is 0.5 wt%～0.6 wt% of steel.
文摘Dibenzoyl peroxide undergoes oxidative addition on metallic copper powder with 2,2′-bipyridine(or imidazole)in a mixed solvent(methanol and tetrahydrofuran),and affords the Cu(Ⅱ)complexes-[Cu(Ce(C_6H_5COO)_2(2,2'-bipy)]H_2O(1) and[Cu(C_6H_5COO)_2(C_3H_4N_2)_2](2).The structure was solved by direct methods and Fourier synthesis.C_(24)H_(20)N_2O_5Cu (1),Mr=479.78,space group P2(1)/c,a=6.986(7), b=18.833(I),c=17.021(3),α=γ=90°,Z=4,V=2218.1~3,Dc=1.443g/cm\+3,R=0.055 Rw=0.062.Complex(2),C_(20)H_(18)N_4O_4Cu(2),Mr=441.74,space group P2(1)/n,a=8.699(4), b=9.840(6),c=12.399(5),α=γ=90°,β=100.8°,Z=4,V=1010.9~3,Dc=1.654g/cm\+3,R=0.055, Rw=0.062.
文摘Yttria stabilized zirconia (YSZ) is a kind of electrolyte materials widely used for solid oxide fuel cell (SOFC). Some rare earth elements (Dy 3+, Yb 3+, Sc 3+, etc), which have similar radii to Zr 4+, can dissolve into ZrO_2, and result in oxygen vacancy and crystal lattice distortion, so enhance its conductivity and lower the activation energy. YSZ electrolyte doped with Sc 3+(Dy 3+) and Yb 3+ were prepared by combustion synthesis. The conductivity is enhanced due to the distortions of crystal lattice and the increase in oxygen transfer passage radii, reaching 0.15 S·cm -1 at 1000 ℃. Crystalline symmetry of ZrO_2 changed from monoclinic to tetragonal, and then to cubic, with the elevation of calcining temperature. SEM photographs show the complex additives promoted growth of ZrO_2. There are some second phases along the grain boundaries, which restricted the further increase of conductivity. The addition of Al 3+ or Ca 2+ improve grain boundary, but lower the high-temperature conductivity.
文摘Piglets’ alactation stress with diarrhea as a main symptom is a serious problem in pig farming. The experiment indicates that the complex premix additive Huzikang duannaibao can be used to control ablactation stress syndromes and its effects are better than that of the common antibiotic ligomycin.
