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2016 Volume 33 Issue 12
2016, 33(12): 1343-1354
doi: 10.11944/j.issn.1000-0518.2016.12.160355
Abstract:
The booming of application of graphene material in biological field makes the study of nano-bio interface of graphene material become a hotspot of nano-bio interface. Biomembrane is the first barrier graphene material encountered when it is presented in a biological environment. Deep understanding the interaction between graphene material and biomembrane is of great significant in design and optimization of functional interface and management of nano-bio effect of graphene-based biomaterial. In this article, we gave a brief introduction of graphene material, systematically summarized the research progress of interfacial interaction between graphene material and model biomembrane during recent years, and presented out the perspective of further development in this field.
The booming of application of graphene material in biological field makes the study of nano-bio interface of graphene material become a hotspot of nano-bio interface. Biomembrane is the first barrier graphene material encountered when it is presented in a biological environment. Deep understanding the interaction between graphene material and biomembrane is of great significant in design and optimization of functional interface and management of nano-bio effect of graphene-based biomaterial. In this article, we gave a brief introduction of graphene material, systematically summarized the research progress of interfacial interaction between graphene material and model biomembrane during recent years, and presented out the perspective of further development in this field.
2016, 33(12): 1355-1365
doi: 10.11944/j.issn.1000-0518.2016.12.160147
Abstract:
Triplex DNA can interfere with gene transcription and expression modulation. It is one kind of important biological macromolecules. The interaction between small molecules and DNA targets plays an important role in the function of drug mediated physiological processes. In the past decades, numerous attempts have been made to screen triplex DNA binders. However, not too many effective methods for screening triplex DNA binders were reported. Basic principles, the screening methods of research and application for the interaction between small ligands and triplex DNA were summarized, including mainly the principle and application of several methods, such as competition dialysis, gold nanoparticle based approach, thermal denaturation method, centrifugal ultrafiltration method, electrospray ionization mass spectroscopy(MS) method, and liquid chromatography-mass spectroscopy(LC-MS) combined method. This review has a general instruction to the research of the interaction between small ligands and triplex DNA.
Triplex DNA can interfere with gene transcription and expression modulation. It is one kind of important biological macromolecules. The interaction between small molecules and DNA targets plays an important role in the function of drug mediated physiological processes. In the past decades, numerous attempts have been made to screen triplex DNA binders. However, not too many effective methods for screening triplex DNA binders were reported. Basic principles, the screening methods of research and application for the interaction between small ligands and triplex DNA were summarized, including mainly the principle and application of several methods, such as competition dialysis, gold nanoparticle based approach, thermal denaturation method, centrifugal ultrafiltration method, electrospray ionization mass spectroscopy(MS) method, and liquid chromatography-mass spectroscopy(LC-MS) combined method. This review has a general instruction to the research of the interaction between small ligands and triplex DNA.
2016, 33(12): 1366-1374
doi: 10.11944/j.issn.1000-0518.2016.12.160102
Abstract:
Phase change materials(PCM) are used for thermal energy storage through the large energy released and received during phase change. Owing to the high energy density, PCM can be utilized in building thermal comforting, concentrated solar power and thermal transport and conversion at high temperature. Heat exchangers are used to transfer thermal energy between fluids and play a crucial role in enhancing energy efficiency of thermal energy storage devices which employ phase change materials as the storage unit. To guarantee the performance stability and usage safety, the compatibility between heat exchangers and phase change materials are extensively investigated. Herein, we give a comprehensive literature review on this topic. The presented overall study can be a reference for heat exchanger material selection.
Phase change materials(PCM) are used for thermal energy storage through the large energy released and received during phase change. Owing to the high energy density, PCM can be utilized in building thermal comforting, concentrated solar power and thermal transport and conversion at high temperature. Heat exchangers are used to transfer thermal energy between fluids and play a crucial role in enhancing energy efficiency of thermal energy storage devices which employ phase change materials as the storage unit. To guarantee the performance stability and usage safety, the compatibility between heat exchangers and phase change materials are extensively investigated. Herein, we give a comprehensive literature review on this topic. The presented overall study can be a reference for heat exchanger material selection.
2016, 33(12): 1375-1382
doi: 10.11944/j.issn.1000-0518.2016.12.160343
Abstract:
One of the important prerequisites of large-area production is that the power conversion efficiency of polymer solar cells is insensitive to the active layer thickness. A novel donor-acceptor copolymer, named poly[N-(2-hexyldecyl)-2,2'-bithiophene-3,3'-dicarboximide-alt-5,5-(2,5-bis(3-(decyloxy)thiophene-2-yl)-thiophene)](PBTI3T-O),with a moderate band gap has been designed and synthesized. PBTI3T-O shows a broad absorption range of 400~720 nm and good solubility in chlorobenzene(CB). The hole mobility of PBTI3T-O and[6,6]-phenyl-C71-butyric acid methyl ester(PC71BM) blend is 5.90×10-3 cm2/(V·s), which is higher than those of most other materials. The excellent charge transport property leads to a power conversion efficiency of 5.56% with a thick active layer of 237 nm. Furthermore, PBTI3T-O based device retains 97% of the highest efficiency with a thickness of ca. 300 nm, indicating its potential application in large-area production.
One of the important prerequisites of large-area production is that the power conversion efficiency of polymer solar cells is insensitive to the active layer thickness. A novel donor-acceptor copolymer, named poly[N-(2-hexyldecyl)-2,2'-bithiophene-3,3'-dicarboximide-alt-5,5-(2,5-bis(3-(decyloxy)thiophene-2-yl)-thiophene)](PBTI3T-O),with a moderate band gap has been designed and synthesized. PBTI3T-O shows a broad absorption range of 400~720 nm and good solubility in chlorobenzene(CB). The hole mobility of PBTI3T-O and[6,6]-phenyl-C71-butyric acid methyl ester(PC71BM) blend is 5.90×10-3 cm2/(V·s), which is higher than those of most other materials. The excellent charge transport property leads to a power conversion efficiency of 5.56% with a thick active layer of 237 nm. Furthermore, PBTI3T-O based device retains 97% of the highest efficiency with a thickness of ca. 300 nm, indicating its potential application in large-area production.
2016, 33(12): 1383-1388
doi: 10.11944/j.issn.1000-0518.2016.12.160363
Abstract:
Resveratrol(Res) binary and ternary solid dispersions solid dispersions with poly(vinylpyrrolidone) (PVP) and hydroxypropylmethylcellulose(HPMC) were prepared by the solvent evaporation. Solid dispersions were characterized by Fourier transform infrared spectroscopy(FTIR), X-ray powder diffraction(XRD) and modulated differential scanning calorimetry(MDSC), and the release profiles were also invested. FTIR results reveal hydrogen bonding formed between Res and polymers. The release profiles of both Res solid dispersions are enhanced. However, XRD and MDSC results show that the miscibility of ternary solid dispersions is better than that of its binary solid dispersions. Under accelerated testing condition(40℃, 75%RH(relative humity)) for 3 months, XRD, MDSC and the release profiles indicate that Res ternary solid dispersions are more stable than that of its binary solid dispersions. The release profiles and stability of Res ternary solid dispersions are improved with the addition of HPMC.
Resveratrol(Res) binary and ternary solid dispersions solid dispersions with poly(vinylpyrrolidone) (PVP) and hydroxypropylmethylcellulose(HPMC) were prepared by the solvent evaporation. Solid dispersions were characterized by Fourier transform infrared spectroscopy(FTIR), X-ray powder diffraction(XRD) and modulated differential scanning calorimetry(MDSC), and the release profiles were also invested. FTIR results reveal hydrogen bonding formed between Res and polymers. The release profiles of both Res solid dispersions are enhanced. However, XRD and MDSC results show that the miscibility of ternary solid dispersions is better than that of its binary solid dispersions. Under accelerated testing condition(40℃, 75%RH(relative humity)) for 3 months, XRD, MDSC and the release profiles indicate that Res ternary solid dispersions are more stable than that of its binary solid dispersions. The release profiles and stability of Res ternary solid dispersions are improved with the addition of HPMC.
2016, 33(12): 1389-1395
doi: 10.11944/j.issn.1000-0518.2016.12.160216
Abstract:
Thermally-responsive PNIPAm-g-cellulose nanofibers hydrogels were prepared by thermally-responsive poly(N-isopropyl acrylamide)(PNIPAm) grafted electrospun cellulose nanofibrous membranes. The effect of mass ratio of monomer and cellulose, reaction temperature, reaction time and amounts of initiator on grafting rate, swelling rate and morphology were investigated. The results show that the optimum reaction condition are as follows:mass ratio of monomer and cellulose in 15:1, reaction temperature at 40℃, reaction time for 3 h and initiator concentration of 10 mmol/L, the grafting rate and swelling rate of PNIPAm-g-Cell at 35% and 31%, respectively. Compared with PNIPAm hydrogels, the lower critical solution temperature(LCST) of PNIPAm-g-Cell hydrogels is obviously increased, indicating that hydrophilic-hydrophobic balance was changed by adding hydrophilic cellulose. Deswelling kinetics of the PNIPAm-g-Cell hydrogels shows that water-retention rate is decreased to 93% and 61% for grafting rate of 25% and 35%, respectively, in initiatory 0.5 min. PNIPAm-g-Cell hydrogels with high grafting rate have greater sensitivity to temperature.
Thermally-responsive PNIPAm-g-cellulose nanofibers hydrogels were prepared by thermally-responsive poly(N-isopropyl acrylamide)(PNIPAm) grafted electrospun cellulose nanofibrous membranes. The effect of mass ratio of monomer and cellulose, reaction temperature, reaction time and amounts of initiator on grafting rate, swelling rate and morphology were investigated. The results show that the optimum reaction condition are as follows:mass ratio of monomer and cellulose in 15:1, reaction temperature at 40℃, reaction time for 3 h and initiator concentration of 10 mmol/L, the grafting rate and swelling rate of PNIPAm-g-Cell at 35% and 31%, respectively. Compared with PNIPAm hydrogels, the lower critical solution temperature(LCST) of PNIPAm-g-Cell hydrogels is obviously increased, indicating that hydrophilic-hydrophobic balance was changed by adding hydrophilic cellulose. Deswelling kinetics of the PNIPAm-g-Cell hydrogels shows that water-retention rate is decreased to 93% and 61% for grafting rate of 25% and 35%, respectively, in initiatory 0.5 min. PNIPAm-g-Cell hydrogels with high grafting rate have greater sensitivity to temperature.
2016, 33(12): 1396-1400
doi: 10.11944/j.issn.1000-0518.2016.12.160116
Abstract:
Poly(vinlytetrazole-co-acrylonitrile)(Poly(VT-co-AN)) was synthesized via partial[3+2] cyclization of the cyano group of polyacrylonitrile, and then hydrolysis of the residual cyano group in basic condition leads to poly(vinyltetrazole-co-acrylic acid)(Poly(VT-co-AA)). The structures of Poly(VT-co-AA) and Poly(VT-co-AN) are characterized by FT-IR and 13C NMR. The results show that poly(VT-co-AN) contains tetrazole, cyano and carboxyl group, and the tetrazole content is 68.6%, which corresponds to the result of acid-base titration. The Poly(VT-co-AA) contains tetrazole and carboxyl group, and shows a higher acid value than Poly(VT-co-AN). The tetrazole content of Poly(VT-co-AA) is 67.6% and corresponds to the n(NaN3)/n(PAN) ratio. Thermogravimetric analysis result shows that Poly(VT-co-AA) decomposes faster, and decomposes fully in 270~285℃.
Poly(vinlytetrazole-co-acrylonitrile)(Poly(VT-co-AN)) was synthesized via partial[3+2] cyclization of the cyano group of polyacrylonitrile, and then hydrolysis of the residual cyano group in basic condition leads to poly(vinyltetrazole-co-acrylic acid)(Poly(VT-co-AA)). The structures of Poly(VT-co-AA) and Poly(VT-co-AN) are characterized by FT-IR and 13C NMR. The results show that poly(VT-co-AN) contains tetrazole, cyano and carboxyl group, and the tetrazole content is 68.6%, which corresponds to the result of acid-base titration. The Poly(VT-co-AA) contains tetrazole and carboxyl group, and shows a higher acid value than Poly(VT-co-AN). The tetrazole content of Poly(VT-co-AA) is 67.6% and corresponds to the n(NaN3)/n(PAN) ratio. Thermogravimetric analysis result shows that Poly(VT-co-AA) decomposes faster, and decomposes fully in 270~285℃.
2016, 33(12): 1401-1407
doi: 10.11944/j.issn.1000-0518.2016.12.160373
Abstract:
3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate(2010P) was adopted as the diluent of 4,4'-methylenebis(N,N-diglycidylaniline) epoxy(AG-80)/Hexahydrophthalic anhydride(HHPA) curing system. Via different testing methods such as viscosity, tensile, high temperature shearing test, differential scanning calorimetry(DSC), and high-power microscope, the effect of diluent on the viscosity, mechanical performances, and thermal properties of epoxy resin were investigated, and the interaction of diluent and epoxy resin was studied, respectively. 2010P was found to improve the fluidity of resin markedly. With increase of 2010P mass fraction, the tensile strength increases at first and then decreases, and the maximum strength value appears at 25% mass fraction. DSC result shows that the glass transition temperature of AG-80 is reduced with the addition of 2010P, nevertheless, the suitable content of 2010P can further enhance the adhesion of AG-80 epoxy under high temperature. When mass fraction of 2010P is 30%, the shear strength of resin is up to 13.78 MPa.
3,4-Epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate(2010P) was adopted as the diluent of 4,4'-methylenebis(N,N-diglycidylaniline) epoxy(AG-80)/Hexahydrophthalic anhydride(HHPA) curing system. Via different testing methods such as viscosity, tensile, high temperature shearing test, differential scanning calorimetry(DSC), and high-power microscope, the effect of diluent on the viscosity, mechanical performances, and thermal properties of epoxy resin were investigated, and the interaction of diluent and epoxy resin was studied, respectively. 2010P was found to improve the fluidity of resin markedly. With increase of 2010P mass fraction, the tensile strength increases at first and then decreases, and the maximum strength value appears at 25% mass fraction. DSC result shows that the glass transition temperature of AG-80 is reduced with the addition of 2010P, nevertheless, the suitable content of 2010P can further enhance the adhesion of AG-80 epoxy under high temperature. When mass fraction of 2010P is 30%, the shear strength of resin is up to 13.78 MPa.
2016, 33(12): 1408-1414
doi: 10.11944/j.issn.1000-0518.2016.12.160399
Abstract:
The structure and properties of polybutadiene rubber(BR) with narrow molecular mass distribution synthesized by rare earth Nd catalysts(NMWD-NdBR) were studied and compared with those of the sample with a wider molecular weight distribution(WMWD-NdBR). The results show that NMWD-NdBR gets a steady rheological behavior under the same rotation rate. The scorch time and the optimum curing point of NMWD-NdBR are similar to those of WMWD-NdBR, but the minimum torque(ML), maximum torque(MH) and mechanical properties of NMWD-NdBR are slightly better than those of WMWD-NdBR. The data of rubber processing analyzer(RPA) show that the Payne effect of NMWD-NdBR are similar to those of WMWD-NdBR, and the hysteresis loss(tanδ) of NMWD-NdBR are superior to those of WMWD-NdBR. The results of tanδ data are in good agreement with those of carbon black dispersion, heat build-up, permanent set, as well as rolling resistance.
The structure and properties of polybutadiene rubber(BR) with narrow molecular mass distribution synthesized by rare earth Nd catalysts(NMWD-NdBR) were studied and compared with those of the sample with a wider molecular weight distribution(WMWD-NdBR). The results show that NMWD-NdBR gets a steady rheological behavior under the same rotation rate. The scorch time and the optimum curing point of NMWD-NdBR are similar to those of WMWD-NdBR, but the minimum torque(ML), maximum torque(MH) and mechanical properties of NMWD-NdBR are slightly better than those of WMWD-NdBR. The data of rubber processing analyzer(RPA) show that the Payne effect of NMWD-NdBR are similar to those of WMWD-NdBR, and the hysteresis loss(tanδ) of NMWD-NdBR are superior to those of WMWD-NdBR. The results of tanδ data are in good agreement with those of carbon black dispersion, heat build-up, permanent set, as well as rolling resistance.
2016, 33(12): 1415-1419
doi: 10.11944/j.issn.1000-0518.2016.12.160054
Abstract:
The porphyrin modified with 5-fluorouracil(5-[2-(5-fluorouracil-3-yl)-ethoxyphenyl]-10,15,20-tri(4-methoxyphenyl) porphyrin) and its two metal porphyrin complexes:5-[2-(5-fluorouracil-3-yl)-ethoxyphenyl]-10,15,20-tri(4-methoxyphenyl) Mn porphyrin and 5-[2-(5-fluorouracil-3-yl)-ethoxyphenyl]-10,15,20-tri(4-methoxyphenyl) Zn porphyrin were synthesized. The structures of the three compounds were characterized by ultraviolet visible spectroscopy(UV-Vis), infred spectroscopy(IR) and proton nuclear magnetic resonance spectroscopy(1H NMR). The antitumor activities of these compounds to A549, Bel7402, HCT-8 were tested using the methyl thiazolyl tetrazolium(MTT) method. The results show that the IC50 value of Mn porphyrin to HCT-8 is 17.8 mg/L.
The porphyrin modified with 5-fluorouracil(5-[2-(5-fluorouracil-3-yl)-ethoxyphenyl]-10,15,20-tri(4-methoxyphenyl) porphyrin) and its two metal porphyrin complexes:5-[2-(5-fluorouracil-3-yl)-ethoxyphenyl]-10,15,20-tri(4-methoxyphenyl) Mn porphyrin and 5-[2-(5-fluorouracil-3-yl)-ethoxyphenyl]-10,15,20-tri(4-methoxyphenyl) Zn porphyrin were synthesized. The structures of the three compounds were characterized by ultraviolet visible spectroscopy(UV-Vis), infred spectroscopy(IR) and proton nuclear magnetic resonance spectroscopy(1H NMR). The antitumor activities of these compounds to A549, Bel7402, HCT-8 were tested using the methyl thiazolyl tetrazolium(MTT) method. The results show that the IC50 value of Mn porphyrin to HCT-8 is 17.8 mg/L.
2016, 33(12): 1420-1427
doi: 10.11944/j.issn.1000-0518.2016.12.160325
Abstract:
Multi-photoemissions from multi-luminescent centers that correspond to multi available sites in a given crystal are frequently noticed in previous works. Depending on the exact type of dopant built into, compounds having multi available sites should correspondingly offer multi luminescent centers, but some kinds of such compounds sometimes exhibit only one luminescent center, exhibiting the "controversial" centers. According to previous works, the akermanite(Ca2MgSi2O7), which has been known as the classical afterglow host for a long term, belongs to this type of compounds having the "controversial" Ca sites. Here we report on utilizing the typical luminescent behavior of the non-rare-earth(non-RE) ion(Bi3+) to explore the issues of "controversial" Ca sites in Ca2MgSi2O7 crystal. Our results show that the excitation bands centering at 250 nm and 276 nm can pump all samples of Ca2MgSi2O7:Bi3+ to exhibit dual Bi3+-related photoemissions centering at 582 nm and~350 nm, respectively. In combination with the crystal structure analysis, the spectral results indicate that there are dual Bi3+ luminescent centers[denoted as Bi3+(Ⅰ) and Bi3+(Ⅱ)] at two different Ca2+ sites coordinating with six- and eight-oxygen atoms in the Ca2MgSi2O7 host. Surprisingly, the spectral results support the existence of the energy transfer from Bi3+(Ⅰ) to Bi3+(Ⅱ) and the process is found to be unidirectional. Further analysis indicated that the relative emission intensity of 582 nm and~350 nm derived from Bi3+(Ⅰ) and Bi3+(Ⅱ) centers is tightly relied on the incident excitation wavelength and the Bi3+ doping contents. Our results clearly prove that there are two available Ca sites instead of only one Ca site in Ca2MgSi2O7 crystal. Because of the reason, this work provides a new insight into verifying the available sites in some unknown or/and well-known crystals from another point of view.
Multi-photoemissions from multi-luminescent centers that correspond to multi available sites in a given crystal are frequently noticed in previous works. Depending on the exact type of dopant built into, compounds having multi available sites should correspondingly offer multi luminescent centers, but some kinds of such compounds sometimes exhibit only one luminescent center, exhibiting the "controversial" centers. According to previous works, the akermanite(Ca2MgSi2O7), which has been known as the classical afterglow host for a long term, belongs to this type of compounds having the "controversial" Ca sites. Here we report on utilizing the typical luminescent behavior of the non-rare-earth(non-RE) ion(Bi3+) to explore the issues of "controversial" Ca sites in Ca2MgSi2O7 crystal. Our results show that the excitation bands centering at 250 nm and 276 nm can pump all samples of Ca2MgSi2O7:Bi3+ to exhibit dual Bi3+-related photoemissions centering at 582 nm and~350 nm, respectively. In combination with the crystal structure analysis, the spectral results indicate that there are dual Bi3+ luminescent centers[denoted as Bi3+(Ⅰ) and Bi3+(Ⅱ)] at two different Ca2+ sites coordinating with six- and eight-oxygen atoms in the Ca2MgSi2O7 host. Surprisingly, the spectral results support the existence of the energy transfer from Bi3+(Ⅰ) to Bi3+(Ⅱ) and the process is found to be unidirectional. Further analysis indicated that the relative emission intensity of 582 nm and~350 nm derived from Bi3+(Ⅰ) and Bi3+(Ⅱ) centers is tightly relied on the incident excitation wavelength and the Bi3+ doping contents. Our results clearly prove that there are two available Ca sites instead of only one Ca site in Ca2MgSi2O7 crystal. Because of the reason, this work provides a new insight into verifying the available sites in some unknown or/and well-known crystals from another point of view.
2016, 33(12): 1428-1434
doi: 10.11944/j.issn.1000-0518.2016.12.160119
Abstract:
A dinuclear cyclometalated iridium-platinum complexIridium[Ⅲ]bis[(2,4-difluorophenyl)-pyridinato-N,C2'] [picolinate]-C6-Paltinum[II] [phenylpyridinato-N,C2'] [picolinate](FIrPPyPt) was designed and synthesized. Its structure and properties were characterized by NMR, elemental analyzer, UV absorption spectroscopy and photoluminescence spectroscopy. The results show that the UV absorption of the complex FIrPPyPt is located between 250 and 450 nm, and the fluorescence emission peak is located at 465 and 493 nm. The electroluminescent devices were made from poly(N-vinylcarbazole)(PVK)+2-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole(PBD) doped with 1%~8% mass fraction of FIrPPyPt complexes. The electroluminescence spectra at different voltages show the characteristic peaks of iridium complexes and platinum complexes located at 400, 500 and 530 nm in blue-green emission zones. The dual core complexes are used for single doped organic white light emitting devices with simple fabrication, good color stability and good reproducibility, it provides a good idea for the single doped white light emitting devices.
A dinuclear cyclometalated iridium-platinum complexIridium[Ⅲ]bis[(2,4-difluorophenyl)-pyridinato-N,C2'] [picolinate]-C6-Paltinum[II] [phenylpyridinato-N,C2'] [picolinate](FIrPPyPt) was designed and synthesized. Its structure and properties were characterized by NMR, elemental analyzer, UV absorption spectroscopy and photoluminescence spectroscopy. The results show that the UV absorption of the complex FIrPPyPt is located between 250 and 450 nm, and the fluorescence emission peak is located at 465 and 493 nm. The electroluminescent devices were made from poly(N-vinylcarbazole)(PVK)+2-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole(PBD) doped with 1%~8% mass fraction of FIrPPyPt complexes. The electroluminescence spectra at different voltages show the characteristic peaks of iridium complexes and platinum complexes located at 400, 500 and 530 nm in blue-green emission zones. The dual core complexes are used for single doped organic white light emitting devices with simple fabrication, good color stability and good reproducibility, it provides a good idea for the single doped white light emitting devices.
2016, 33(12): 1435-1440
doi: 10.11944/j.issn.1000-0518.2016.12.160073
Abstract:
A two-spin complex{[Zn(acac)2](NITQ)2}·2CH2Cl2(acac=acetylaceonate anion, NITQ=2-(2-quinoxalinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) was synthesized from a quinoxalinyl substituted nitroxide radical. The X-ray analysis of the single crystal reveals that two NITQ radicals act as monodentate ligands coordinated to Zn2+ to form a two-spin octahedral complex. The magnetic study shows that two NITQ radicals have ferromagnetic interaction, the Curie constant C=0.7242 cm3·K/mol and Weiss constant θ=0.5958 K.
A two-spin complex{[Zn(acac)2](NITQ)2}·2CH2Cl2(acac=acetylaceonate anion, NITQ=2-(2-quinoxalinyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) was synthesized from a quinoxalinyl substituted nitroxide radical. The X-ray analysis of the single crystal reveals that two NITQ radicals act as monodentate ligands coordinated to Zn2+ to form a two-spin octahedral complex. The magnetic study shows that two NITQ radicals have ferromagnetic interaction, the Curie constant C=0.7242 cm3·K/mol and Weiss constant θ=0.5958 K.
2016, 33(12): 1441-1447
doi: 10.11944/j.issn.1000-0518.2016.12.160088
Abstract:
Silver vanadium tetraoxide and graphene oxide(Ag3VO4/GO) composites were prepared by Hummers and liquid phase precipitation methods respectively. The obtained samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), and ultraviolet-visible(UV-Vis) diffuse reflectance spectroscopy. The effect of GO content on the photocatalytic activity of Ag3VO4 was evaluated by photocatalytic degradation of methyl orange(MO) under visible light irradiation(λ≥420 nm). The results show that GO dopped Ag3VO4 nanoparticles can improve the degradation efficiency. At the optimal GO content(2% mass fraction), the degradation rate of MO over GO/Ag3VO4 is 89% after 30 min of light irradiation, exhibiting 1.6 times higher activity than that of pure Ag3VO4.
Silver vanadium tetraoxide and graphene oxide(Ag3VO4/GO) composites were prepared by Hummers and liquid phase precipitation methods respectively. The obtained samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), and ultraviolet-visible(UV-Vis) diffuse reflectance spectroscopy. The effect of GO content on the photocatalytic activity of Ag3VO4 was evaluated by photocatalytic degradation of methyl orange(MO) under visible light irradiation(λ≥420 nm). The results show that GO dopped Ag3VO4 nanoparticles can improve the degradation efficiency. At the optimal GO content(2% mass fraction), the degradation rate of MO over GO/Ag3VO4 is 89% after 30 min of light irradiation, exhibiting 1.6 times higher activity than that of pure Ag3VO4.
2016, 33(12): 1448-1454
doi: 10.11944/j.issn.1000-0518.2016.12.160056
Abstract:
The composites of polyaniline(PANI) coating monthmorillonite-supported nitrogen-doped carbon(NMC) were prepared by in situ polymerization of aniline upon NMC in the hydrochloric acid(HCl) solution and the mixed acid solution composed of HCl acid and D-camphorsulfonic acid(DCSA). Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy were employed to investigate the effect of the doping acid on the crystallization property. NMC@PANI doped with HCl has a short stick morphology, while one doped with HCl/DCSA exhibits a granular and flaked morphology and its crystallization degree is higher than that of the former. NMC@PANI doped with HCl/DCSA has a specific capacitance of 412.5 F/g at 0.5 A/g, which is increased by 24.1% compared to that of NMC@PANI doped with HCl, and shows a lower equivalent series resistance and charge transfer resistance. However, the capacitance of NMC@PANI doped with HCl retains 81.4% at large charge/discharge current, higher than 58.4% of one doped with HCl/DCSA.
The composites of polyaniline(PANI) coating monthmorillonite-supported nitrogen-doped carbon(NMC) were prepared by in situ polymerization of aniline upon NMC in the hydrochloric acid(HCl) solution and the mixed acid solution composed of HCl acid and D-camphorsulfonic acid(DCSA). Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy were employed to investigate the effect of the doping acid on the crystallization property. NMC@PANI doped with HCl has a short stick morphology, while one doped with HCl/DCSA exhibits a granular and flaked morphology and its crystallization degree is higher than that of the former. NMC@PANI doped with HCl/DCSA has a specific capacitance of 412.5 F/g at 0.5 A/g, which is increased by 24.1% compared to that of NMC@PANI doped with HCl, and shows a lower equivalent series resistance and charge transfer resistance. However, the capacitance of NMC@PANI doped with HCl retains 81.4% at large charge/discharge current, higher than 58.4% of one doped with HCl/DCSA.
2016, 33(12): 1455-1461
doi: 10.11944/j.issn.1000-0518.2016.12.160086
Abstract:
In order to study the electrochemical behavior of aluminum-lead-silver alloy anodes based on aluminum in the systems of containing fluoride ion and sulfuric acid. Testing cyclic voltammetry and galvanostatic polarization curves of Al/Pb-0.2%Ag anode in different concentrations of fluoride ion and sulfuric acid systems, respectively. The results show that oxidation and the reduction that tetravalence switch to bivalence of lead on the anode surface were inhibited, though the reduction tetravalence switch to simple substance of lead was promoted, and oxygen evolution reaction was inhibited while oxidation film-forming was promoted with increasing F- concentration. The oxidation and reduction of lead are increased at first then decreased with the increasing sulfuric acid concentration. They are the most favorable conditions for oxidation film-forming and oxygen evolution reaction of the anode at sulfuric acid and F- concentration of 20 g/L and 0.1 g/L.
In order to study the electrochemical behavior of aluminum-lead-silver alloy anodes based on aluminum in the systems of containing fluoride ion and sulfuric acid. Testing cyclic voltammetry and galvanostatic polarization curves of Al/Pb-0.2%Ag anode in different concentrations of fluoride ion and sulfuric acid systems, respectively. The results show that oxidation and the reduction that tetravalence switch to bivalence of lead on the anode surface were inhibited, though the reduction tetravalence switch to simple substance of lead was promoted, and oxygen evolution reaction was inhibited while oxidation film-forming was promoted with increasing F- concentration. The oxidation and reduction of lead are increased at first then decreased with the increasing sulfuric acid concentration. They are the most favorable conditions for oxidation film-forming and oxygen evolution reaction of the anode at sulfuric acid and F- concentration of 20 g/L and 0.1 g/L.
2016, 33(12): 1462-1464
doi: 10.11944/j.issn.1000-0518.2016.12.160300
Abstract:
We reported a novel cerium-copper redox flow battery and, the cyclic voltammetry characteristics of the Ce3+/Ce4+, Cu2+/Cu0 redox couples were studied. Moreover, a laboratory level redox flow battery was assembled to study the charge-discharge performance of this battery. The test result suggests that the battery delivers a desirable discharge voltage of approximately 1.0 V, with a high average coulombic efficiency(CE) of 100% and energy efficiency(EE) of over 75% during 100 cycles at 45 mA charge-discharge current.
We reported a novel cerium-copper redox flow battery and, the cyclic voltammetry characteristics of the Ce3+/Ce4+, Cu2+/Cu0 redox couples were studied. Moreover, a laboratory level redox flow battery was assembled to study the charge-discharge performance of this battery. The test result suggests that the battery delivers a desirable discharge voltage of approximately 1.0 V, with a high average coulombic efficiency(CE) of 100% and energy efficiency(EE) of over 75% during 100 cycles at 45 mA charge-discharge current.
