Two systems of La_(2-x)Sr_xCuO_(4±λ) and La_(2-x)Th_xCuO_(4±λ) mixed oxides with K_2NiF_4structure were synthesized.The compositions and structures of the catalysts were characterized by means of XRD,XPS,c...Two systems of La_(2-x)Sr_xCuO_(4±λ) and La_(2-x)Th_xCuO_(4±λ) mixed oxides with K_2NiF_4structure were synthesized.The compositions and structures of the catalysts were characterized by means of XRD,XPS,chemical analysis and so on.The catalytic behavior for the direct decomposition of NO has been investigated.The results show that the catalytic activity is closely related to the oxygen vacancy and lower valence metallic ion in the direct decomposition of NO.The presence of oxygen vacancy is necessary for mixed oxide to have steady activity in NO decomposition.展开更多
The serious surface charge recombination and fatigued photogenerated carriers transfer of the BiVO_(4)photoanode restrict its photoelectrochemical(PEC)water splitting performance.In this work,nickel fluoride(NiF_(2))i...The serious surface charge recombination and fatigued photogenerated carriers transfer of the BiVO_(4)photoanode restrict its photoelectrochemical(PEC)water splitting performance.In this work,nickel fluoride(NiF_(2))is applied to revamp pure BiVO_(4)photoanode by using a facile electrodeposition method.As a result,the asprepared NiF_(2)/BiVO_(4)photoanode increases the dramatic photocurrent density by approximately 180%compared with the pristine BiVO_(4)photoanode.Furthermore,the correlative photon-to-current conversion efficiency,the charge injection,and the separation efficiency,as well as the hydrogen generation of the composite photoanode have been memorably enhanced due to the synergy of NiF_(2)and BiVO_(4).This study may furnish a dependable guidance in fabricating the fluoride-based compound/semiconductor composite photoanode system.展开更多
K_2NiF_4 type compounds Sm_(2-x)Sr_x CuO_4 (0 ≤ x ≤ 1.2) were prepared.Rietveld refinement of powder diffraction data shows that the crystal system of these compoundsbelongs to T' type tetragonal structure of sp...K_2NiF_4 type compounds Sm_(2-x)Sr_x CuO_4 (0 ≤ x ≤ 1.2) were prepared.Rietveld refinement of powder diffraction data shows that the crystal system of these compoundsbelongs to T' type tetragonal structure of space group I4/mmm , and the addition of Sr causes adramatic shift of the O(Ⅰ) ions along the c axis from Sm (Sr) toward Cu while scarcely affectingthe Cu―O (Ⅱ) bond in basal CuO_4 plane. From XRD data, it can be seen that when 0.0 ≤ x ≤ 0.6,Sm_(2-x)Sr_xCuO_4 belongs to a single-phase K_2NiF_4 type structure, while at x ≥ 0.7, both thefree SrO phase and the CuO phase exist in these compounds. From the results of XPS and Rietveldrefinement, it can be seen that after replacing Sm^(3+) with Sr^(2+) of lower valence, the valenceof Cu and Sm does not change apparently, and thus some defect must be formed at the oxygen ionpositions and/or position A on A_2BO_4 to keep charge balance and to stabilize the structure.展开更多
A new ditransition-metal catalyst system TiC1.-NiC1_2,/MgC1_2,-SiO_2,/AlR_3 was prepared. Gas phase polymerization of ethylene with the catalysts has been studied. The kinetic curves of gas phase polymerization showed...A new ditransition-metal catalyst system TiC1.-NiC1_2,/MgC1_2,-SiO_2,/AlR_3 was prepared. Gas phase polymerization of ethylene with the catalysts has been studied. The kinetic curves of gas phase polymerization showed a decline. The catalysts efficiency and polymerization reaction rates have a optimum value when Ni content of the catalysts was 12.5%(mol).The products obtained are branched polyethylene.展开更多
A series of LnSrNiO_4(A_2BO_4, Ln=La, Pr, Nd, Sm, Gd) mixed oxides with K_2NiF_4 structure, in which Asite(Sr) was partly substituted by individual light rare earth element, was prepared. The solid state physicochemic...A series of LnSrNiO_4(A_2BO_4, Ln=La, Pr, Nd, Sm, Gd) mixed oxides with K_2NiF_4 structure, in which Asite(Sr) was partly substituted by individual light rare earth element, was prepared. The solid state physicochemical properties including crystal structure, defect structure, IR spectrum, valence state of Bsite ion, nonstoichiometric oxygen, oxygenous species, the properties of oxidation and reduction etc. as well as the catalytic behavior for NO decomposition on these mixed oxides were investigated. The results show that all of these mixed oxide catalysts have high activity for the direct decomposition of NO(at 900 ℃ the conversion of NO is more than 90%). The effect of the substitution of light rare earth elements at Asite on catalytic behavior for NO decomposition was elucidated.展开更多
The aim of this study was to investigate the role of selenoprotein M(SelM)in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin.At 21 d after ...The aim of this study was to investigate the role of selenoprotein M(SelM)in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin.At 21 d after intraperitoneal injection of nickel chloride(NiCl_(2))and/or melatonin into male wild-type(WT)and SelM knockout(KO)C57BL/6J mice,NiCl_(2)was found to induce changes in the microstructure and ultrastructure of the hearts of both WT and SelM KO mice,which were caused by oxidative stress,endoplasmic reticulum stress,and apoptosis,as evidenced by decreases in malondialdehyde(MDA)content and total antioxidant capacity(T-AOC)activity.Changes in the messenger RNA(mRNA)and protein expression of genes related to endoplasmic reticulum stress(activating transcription factor 4(ATF4),inositol-requiring protein 1(IRE1),c-Jun N-terminal kinase(JNK),and C/EBP homologous protein(CHOP))and apoptosis(B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),Caspase-3,Caspase-9,and Caspase-12)were also observed.Notably,the observed damage was worse in SelM KO mice.Furthermore,melatonin alleviated the heart injury caused by NiCl_(2)in WT mice but could not exert a good protective effect in the heart of SelM KO mice.Overall,the findings suggested that the antioxidant capacity of SelM,as well as its modulation of endoplasmic reticulum stress and apoptosis,plays important roles in nickel-induced heart injury.展开更多
文摘Two systems of La_(2-x)Sr_xCuO_(4±λ) and La_(2-x)Th_xCuO_(4±λ) mixed oxides with K_2NiF_4structure were synthesized.The compositions and structures of the catalysts were characterized by means of XRD,XPS,chemical analysis and so on.The catalytic behavior for the direct decomposition of NO has been investigated.The results show that the catalytic activity is closely related to the oxygen vacancy and lower valence metallic ion in the direct decomposition of NO.The presence of oxygen vacancy is necessary for mixed oxide to have steady activity in NO decomposition.
基金This work was financially supported by the National Key Research and Development Program of China(Grant No.2017YFC0602306)the National Natural Science Foundation of China(Grant No.21808189)National Natural Science Foundation of Gansu Province(Grant No.20JR5RA523).
文摘The serious surface charge recombination and fatigued photogenerated carriers transfer of the BiVO_(4)photoanode restrict its photoelectrochemical(PEC)water splitting performance.In this work,nickel fluoride(NiF_(2))is applied to revamp pure BiVO_(4)photoanode by using a facile electrodeposition method.As a result,the asprepared NiF_(2)/BiVO_(4)photoanode increases the dramatic photocurrent density by approximately 180%compared with the pristine BiVO_(4)photoanode.Furthermore,the correlative photon-to-current conversion efficiency,the charge injection,and the separation efficiency,as well as the hydrogen generation of the composite photoanode have been memorably enhanced due to the synergy of NiF_(2)and BiVO_(4).This study may furnish a dependable guidance in fabricating the fluoride-based compound/semiconductor composite photoanode system.
基金theNaturalScienceFoundationofZhejiangProvince (No .2 92 0 33)
文摘K_2NiF_4 type compounds Sm_(2-x)Sr_x CuO_4 (0 ≤ x ≤ 1.2) were prepared.Rietveld refinement of powder diffraction data shows that the crystal system of these compoundsbelongs to T' type tetragonal structure of space group I4/mmm , and the addition of Sr causes adramatic shift of the O(Ⅰ) ions along the c axis from Sm (Sr) toward Cu while scarcely affectingthe Cu―O (Ⅱ) bond in basal CuO_4 plane. From XRD data, it can be seen that when 0.0 ≤ x ≤ 0.6,Sm_(2-x)Sr_xCuO_4 belongs to a single-phase K_2NiF_4 type structure, while at x ≥ 0.7, both thefree SrO phase and the CuO phase exist in these compounds. From the results of XPS and Rietveldrefinement, it can be seen that after replacing Sm^(3+) with Sr^(2+) of lower valence, the valenceof Cu and Sm does not change apparently, and thus some defect must be formed at the oxygen ionpositions and/or position A on A_2BO_4 to keep charge balance and to stabilize the structure.
文摘A new ditransition-metal catalyst system TiC1.-NiC1_2,/MgC1_2,-SiO_2,/AlR_3 was prepared. Gas phase polymerization of ethylene with the catalysts has been studied. The kinetic curves of gas phase polymerization showed a decline. The catalysts efficiency and polymerization reaction rates have a optimum value when Ni content of the catalysts was 12.5%(mol).The products obtained are branched polyethylene.
文摘A series of LnSrNiO_4(A_2BO_4, Ln=La, Pr, Nd, Sm, Gd) mixed oxides with K_2NiF_4 structure, in which Asite(Sr) was partly substituted by individual light rare earth element, was prepared. The solid state physicochemical properties including crystal structure, defect structure, IR spectrum, valence state of Bsite ion, nonstoichiometric oxygen, oxygenous species, the properties of oxidation and reduction etc. as well as the catalytic behavior for NO decomposition on these mixed oxides were investigated. The results show that all of these mixed oxide catalysts have high activity for the direct decomposition of NO(at 900 ℃ the conversion of NO is more than 90%). The effect of the substitution of light rare earth elements at Asite on catalytic behavior for NO decomposition was elucidated.
基金supported by the Heilongjiang Provincial Natural Science Foundation for Outstanding Youth(No.YQ2021C021),China。
文摘The aim of this study was to investigate the role of selenoprotein M(SelM)in endoplasmic reticulum stress and apoptosis in nickel-exposed mouse hearts and to explore the detoxifying effects of melatonin.At 21 d after intraperitoneal injection of nickel chloride(NiCl_(2))and/or melatonin into male wild-type(WT)and SelM knockout(KO)C57BL/6J mice,NiCl_(2)was found to induce changes in the microstructure and ultrastructure of the hearts of both WT and SelM KO mice,which were caused by oxidative stress,endoplasmic reticulum stress,and apoptosis,as evidenced by decreases in malondialdehyde(MDA)content and total antioxidant capacity(T-AOC)activity.Changes in the messenger RNA(mRNA)and protein expression of genes related to endoplasmic reticulum stress(activating transcription factor 4(ATF4),inositol-requiring protein 1(IRE1),c-Jun N-terminal kinase(JNK),and C/EBP homologous protein(CHOP))and apoptosis(B-cell lymphoma-2(Bcl-2),Bcl-2-associated X protein(Bax),Caspase-3,Caspase-9,and Caspase-12)were also observed.Notably,the observed damage was worse in SelM KO mice.Furthermore,melatonin alleviated the heart injury caused by NiCl_(2)in WT mice but could not exert a good protective effect in the heart of SelM KO mice.Overall,the findings suggested that the antioxidant capacity of SelM,as well as its modulation of endoplasmic reticulum stress and apoptosis,plays important roles in nickel-induced heart injury.
