A kinetic study of the electron-transfer in the reaction of tribenzylchlorotin with potassium 12-tungsto cobalt （Ⅲ） ate ion, Ks[CoW12O40], abbreviated as Co（III）W, has been performed in different solvents. The st...A kinetic study of the electron-transfer in the reaction of tribenzylchlorotin with potassium 12-tungsto cobalt （Ⅲ） ate ion, Ks[CoW12O40], abbreviated as Co（III）W, has been performed in different solvents. The studies were carried out in methanol, ethanol, acetonitrile and acetic acid/water. The rate constants, reaction rates and activation parameters were calculated. Our findings show that the rate of disappearance of the Co（Ⅲ） is pseudo-first order. The kinetic data is strongly affected by used solvents. The maximum and minimum rate constants were achieved in the ethanol and acetic acid/water （70/30） as a solvent, respectively. In all of the used solvents, negative value of activation entropies was observed, but negative activation enthalpies are observed in methanol, ethanol and acetonitrile. The reaction rate is increased with increase of Co（Ⅲ） concentration. ？2009 Fatemeh E Bamoharram. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
Nano Research volume 13,pages2268–2279(2020)Cite this article 131 Accesses 1 Altmetric Metrics details Abstract Insufficient angiogenesis in the chronic wound of the diabetic is one of the most important causes that ...Nano Research volume 13,pages2268–2279(2020)Cite this article 131 Accesses 1 Altmetric Metrics details Abstract Insufficient angiogenesis in the chronic wound of the diabetic is one of the most important causes that making the wound unable to heal itself.In this work,a cobalt-based metal–organic framework(ZIF-67)was introduced as a carrier for loading a pro-angiogenic small molecular drug(dimethyloxalylglycine,DMOG).To achieve a long-term angiogenic therapy on the diabetic wound beds,a dual cooperative controllable release system has been designed by incorporating the drug-loaded ZIF-67 nanoparticles into the micro-patterned PLLA/Gelatin nanofibrous scaffolds.The results showed that DMOG was incorporated into ZIF-67 with a high loading ratio(359.12 mg/g),and the drug-loaded ZIF-67 nanoparticles were well embedded in the circular patterned scaffold.Notably,the DMOG as well as Co ions could continuously release from the scaffold for more than 15 days.The in vitro studies showed that the released Co ions and DMOG from the micropatterned nanofibrous scaffolds could synergistically promote the proliferation,migration and tube formation of the human umbilical vein endothelial cells(HUVECs)by inducing a hypoxia response and upregulating the expression of angiogenesis-related genes such as HIF-1α,VEGF and e-NOS.Furthermore,the in vivo results demonstrated that the composite scaffolds could significantly enhance angiogenesis,collagen deposition and eliminate inflammation in the diabetes wounds.These results indicate that the cobalt-based metal–organic framework as a dual cooperative controllable release system provides a new strategy for enhancing angiogenesis and promoting diabetic wound healing.展开更多
Despite carbonaceous materials are widely employed as commercial negative electrodes for lithium ion battery, an urge requirement for new electrode materials that meet the needs of high energy density, long cycle life...Despite carbonaceous materials are widely employed as commercial negative electrodes for lithium ion battery, an urge requirement for new electrode materials that meet the needs of high energy density, long cycle life, low cost and safety is still underway. A number of cobalt-based compounds（Co（OH）_2, Co_3O_4, CoN, CoS,CoP, NiCo_2O_4, etc.） have been developed over the past years as promising anode materials for lithium ion batteries（LIBs） due to their high theoretical capacity, rich redox reaction and adequate cyclability. The LIBs performances of the cobalt-based compounds have been significantly improved in recent years, and it is anticipated that these materials will become a tangible reality for practical applications in the near future. However, the different types of cobalt-based compounds will result in diverse electrochemical performance. This review briefly analyzes recent progress in this field, especially highlights the synthetic approaches and the prepared nanostructures of the diverse cobalt-based compounds and their corresponding performances in LIBs, including the storage capacity, rate capability, cycling stability and so on.展开更多
A novel Co(Ⅱ)-Na(Ⅰ) heterometallic coordination polymer{[CoNa(NTA)(H_2O)_3]·2H_2O}_n (NTA = nitrilotriacetate) was synthesized and characterized byelemental analysis and X-ray diffraction study. The electrochem...A novel Co(Ⅱ)-Na(Ⅰ) heterometallic coordination polymer{[CoNa(NTA)(H_2O)_3]·2H_2O}_n (NTA = nitrilotriacetate) was synthesized and characterized byelemental analysis and X-ray diffraction study. The electrochemical behavior in aqueous solution wasmeasured by cyclic voltamnietry, indicating a quasi-reversible process. The complex crystallizes inthe orthorhombic space group Pbca with the cell parameters a = 1.47276(3) nm, b=0.97280(3) nm, c =1.92946(6) nm, V = 2.76434(13) nm^3, Z = 8. In the title complex, there are two kinds of zigzagchains which interconnect together to form 2D network. One stretches along the b-axis, comprisingCo(Ⅱ) ions, the other stretches along the c-axis, comprising Na(Ⅰ) ions.展开更多
文摘A kinetic study of the electron-transfer in the reaction of tribenzylchlorotin with potassium 12-tungsto cobalt （Ⅲ） ate ion, Ks[CoW12O40], abbreviated as Co（III）W, has been performed in different solvents. The studies were carried out in methanol, ethanol, acetonitrile and acetic acid/water. The rate constants, reaction rates and activation parameters were calculated. Our findings show that the rate of disappearance of the Co（Ⅲ） is pseudo-first order. The kinetic data is strongly affected by used solvents. The maximum and minimum rate constants were achieved in the ethanol and acetic acid/water （70/30） as a solvent, respectively. In all of the used solvents, negative value of activation entropies was observed, but negative activation enthalpies are observed in methanol, ethanol and acetonitrile. The reaction rate is increased with increase of Co（Ⅲ） concentration. ？2009 Fatemeh E Bamoharram. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金This work was supported by the Natural Science Foundation of Shanghai(No.19ZR1437800).
文摘Nano Research volume 13,pages2268–2279(2020)Cite this article 131 Accesses 1 Altmetric Metrics details Abstract Insufficient angiogenesis in the chronic wound of the diabetic is one of the most important causes that making the wound unable to heal itself.In this work,a cobalt-based metal–organic framework(ZIF-67)was introduced as a carrier for loading a pro-angiogenic small molecular drug(dimethyloxalylglycine,DMOG).To achieve a long-term angiogenic therapy on the diabetic wound beds,a dual cooperative controllable release system has been designed by incorporating the drug-loaded ZIF-67 nanoparticles into the micro-patterned PLLA/Gelatin nanofibrous scaffolds.The results showed that DMOG was incorporated into ZIF-67 with a high loading ratio(359.12 mg/g),and the drug-loaded ZIF-67 nanoparticles were well embedded in the circular patterned scaffold.Notably,the DMOG as well as Co ions could continuously release from the scaffold for more than 15 days.The in vitro studies showed that the released Co ions and DMOG from the micropatterned nanofibrous scaffolds could synergistically promote the proliferation,migration and tube formation of the human umbilical vein endothelial cells(HUVECs)by inducing a hypoxia response and upregulating the expression of angiogenesis-related genes such as HIF-1α,VEGF and e-NOS.Furthermore,the in vivo results demonstrated that the composite scaffolds could significantly enhance angiogenesis,collagen deposition and eliminate inflammation in the diabetes wounds.These results indicate that the cobalt-based metal–organic framework as a dual cooperative controllable release system provides a new strategy for enhancing angiogenesis and promoting diabetic wound healing.
基金financially supported by the‘‘1000 Talents Recruitment Program’’of Chinese government,University of Science and Technology Beijingthe Fundamental Research Funds for the Central Universities(No.FRF-TP-16-070A1)
文摘Despite carbonaceous materials are widely employed as commercial negative electrodes for lithium ion battery, an urge requirement for new electrode materials that meet the needs of high energy density, long cycle life, low cost and safety is still underway. A number of cobalt-based compounds（Co（OH）_2, Co_3O_4, CoN, CoS,CoP, NiCo_2O_4, etc.） have been developed over the past years as promising anode materials for lithium ion batteries（LIBs） due to their high theoretical capacity, rich redox reaction and adequate cyclability. The LIBs performances of the cobalt-based compounds have been significantly improved in recent years, and it is anticipated that these materials will become a tangible reality for practical applications in the near future. However, the different types of cobalt-based compounds will result in diverse electrochemical performance. This review briefly analyzes recent progress in this field, especially highlights the synthetic approaches and the prepared nanostructures of the diverse cobalt-based compounds and their corresponding performances in LIBs, including the storage capacity, rate capability, cycling stability and so on.
基金ProjectsupportedbytheEducationCommissionofZhejiangProvince (No .2 0 0 10 12 9)and"5 5 1"DistinguishedPersonFoundationofWenzhou
文摘A novel Co(Ⅱ)-Na(Ⅰ) heterometallic coordination polymer{[CoNa(NTA)(H_2O)_3]·2H_2O}_n (NTA = nitrilotriacetate) was synthesized and characterized byelemental analysis and X-ray diffraction study. The electrochemical behavior in aqueous solution wasmeasured by cyclic voltamnietry, indicating a quasi-reversible process. The complex crystallizes inthe orthorhombic space group Pbca with the cell parameters a = 1.47276(3) nm, b=0.97280(3) nm, c =1.92946(6) nm, V = 2.76434(13) nm^3, Z = 8. In the title complex, there are two kinds of zigzagchains which interconnect together to form 2D network. One stretches along the b-axis, comprisingCo(Ⅱ) ions, the other stretches along the c-axis, comprising Na(Ⅰ) ions.
