Recent studies revealed that the increased level of hypochlorous acid(HOCl)may be deemed to be one of the signs of chronic inflammatory joint disease.Accordingly,the development of effective methods for rapid and accu...Recent studies revealed that the increased level of hypochlorous acid(HOCl)may be deemed to be one of the signs of chronic inflammatory joint disease.Accordingly,the development of effective methods for rapid and accurate detection or monitoring of HOCl in vivo is of great significance for further understanding the role of HOCl in rheumatoid arthritis(RA).Herein,a ratiometric near-infrared(NIR)fluorescent probe(PTA)was reported for the detection and monitoring of HOCl.In the presence of HOCl,the electron-rich S atom and C=C double bond of probe PTA were oxidized in sequence,resulting in the significant hypochromatic shift and decline of absorption spectra.Simultaneously,the intramolecular charge transfer(ICT)process of PTA is inhibited,causing the intrinsic fluorescence emission of PTA shift from 680 to 550 nm.PTA-based test paper strips were successfully prepared and applied to determinate HOCl in actual water samples by“naked eye”colorimetric method.PTA features NIR emission,large Stokes shift(200 nm),low cytotoxicity,high sensitivity(33.9 nM),and short response time(45 s),which enable it to be successfully utilized for imaging endogenous and exogenous HOCl in living zebrafish and mice.More importantly,PTA shows remarkable effectiveness for the monitoring of HOCl-mediated treatment response to RA.Consequently,PTA provides a new approach to further understand the role of HOCl in RA and evaluate the drug treatment efficiency of RA.展开更多
A novel photovoltaic cell with an active layer of poly(phenyleneethynylene) (PPE)/C60/N,N'-diphenyl-N,N'-di-(m-tolyl)-p-benzidine (TPD) is designed. In the active layer, PPE is the major component; C60 and T...A novel photovoltaic cell with an active layer of poly(phenyleneethynylene) (PPE)/C60/N,N'-diphenyl-N,N'-di-(m-tolyl)-p-benzidine (TPD) is designed. In the active layer, PPE is the major component; C60 and TPD are the minor ones. Compared with a control BHJ device based on PPE/C60, the short circuit current density Jsc is increased by 1 order of magnitude, and the whole device performance is increased greatly, however the open circuit voltage Voc is largely decreased. The possible mechanism of the improved performance may be as follows: In the PPE/C60/TPD device, PPE, C60, and TPD serve as the energy harvesting material, the electron transport material, and the hole transport material, respectively. As the TPD and C60 are spatially separated by PPE, the charge recombination is effectively retarded.展开更多
The positively charged single walled carbon nanotubes (SWNTs^+) were prepared by conjugating with -CONH-C6H12-NH3^+. The double strand DNA (dsDNA) chains were loaded onto SWNTs^+ via the electrostatic interacti...The positively charged single walled carbon nanotubes (SWNTs^+) were prepared by conjugating with -CONH-C6H12-NH3^+. The double strand DNA (dsDNA) chains were loaded onto SWNTs^+ via the electrostatic interactions. SWNTs^+ shows improved loading efficiency (353.5 μg/mg) toward dsDNA compared with that of charged free single walled carbon nanotubes (SWNTs) (82.9 μg/mg).展开更多
Efficient bifunctional OER/ORR catalysts are crucial for the further development of zinc-air battery. From a sustainable point of view, it is important that electrocatalysts are efficient, low cost, and composed of ab...Efficient bifunctional OER/ORR catalysts are crucial for the further development of zinc-air battery. From a sustainable point of view, it is important that electrocatalysts are efficient, low cost, and composed of abundant resources instead of scarce metals. Due to their good conductivity, low cost, and strong durability, carbon-based materials are considered a promising alternative in the field of commercial zinc-air battery catalysts. Herein, we briefly introduce the zinc-air battery and then summarize recent progress in the development of carbon-based bifunctional catalysts by defect engineering, heteroatom doping and metal doping. Finally, we discuss the main challenges and prospects for the future development of carbon-based bifunctional oxygen catalysts.展开更多
A new 1D coordination polymer [Co(bpp)3Cl2(H2O)2]n 1 (bpp = 1,3-bis(4-pyridyl)-propane) was synthesized and characterized by elemental analysis,IR spectrum and single-crystal X-ray diffraction. The crystal bel...A new 1D coordination polymer [Co(bpp)3Cl2(H2O)2]n 1 (bpp = 1,3-bis(4-pyridyl)-propane) was synthesized and characterized by elemental analysis,IR spectrum and single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system,space group Ibca with a = 16.569(9),b = 17.240(10),c = 27.087(16) ,V = 7738(8) 3,Z = 8,Dc = 1.306 g/cm3,Mr = 760.65,λ(MoKa) = 0.71073 ,μ = 0.623 mm1,F(000) = 3192,the final R = 0.0678 and wR = 0.2011. The Co(II) atom is coordinated in a slightly distorted octahedral CoN4Cl2 geometry by two Cl atoms in the axial positions,four N atoms from the two bridging bpp ligands and two pendant bpp ligands. The CoN4Cl2 octahedra are connected by the bridging bpp ligands to form a 1D neutral coordination polymer chain. The chains are linked by face-to-face π-π interactions between adjacent pendant bpp ligands to give rise to a 3D supramolecular architecture. The photoluminescent investigation indicates that the emission of 1 is attributed to ligand-centered emission. The variable-temperature magnetic susceptibility measurement shows weak antiferromagnetic behavior in the coπmplex.展开更多
A new mononuclear Cu(Ⅱ) dithiocarbamate complex CuI(prdtc)(phen) 1 (prdtc = N-pyrrolidinyldithiocarbamate, phen = 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR spectrum, and...A new mononuclear Cu(Ⅱ) dithiocarbamate complex CuI(prdtc)(phen) 1 (prdtc = N-pyrrolidinyldithiocarbamate, phen = 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 8.7110(9), b = 14.7143(14), c = 14.8507(15) A, β = 109.721(6)°, V = 1791.9(3) A3, Z = 4, Dc = 1.916 g/cm3, CI7H16CulN3S2, Mr = 516.89, λ(MoKa) = 0.71073A,μ = 3.178 mm^-1, F(000) = 1012, the final R = 0.0369 and wR = 0.0987. A total of 4082 unique reflections were collected, of which 2916 with I 〉 2σ(I) were observed. The Cu(Ⅱ) atom is five-coordinated in a distorted square-pyramidal geometry by one I atom in the apical position, two S atoms from a prdtc ligand and two N atoms from a phen ligand in the basal plane. There exist face-to-face aromatic π-π stacking interactions between adjacent phen ligands stabilizing the structure and making the complex assemble into a 1D structure along the a axis. It can be concluded that the difference of the dtc flexibility and reaction conditions result in the structural difference between complex 1 and CuI(dmdtc)(phen) (dmdtc = N, N-dimethyldithiocarbamate).展开更多
The role of three highly conserved insulin residues Tyr^B26 was studied to better understand the relationship between insulin and receptor from rat adipose tissue plasma membranes, lnsulin analogues with a single amin...The role of three highly conserved insulin residues Tyr^B26 was studied to better understand the relationship between insulin and receptor from rat adipose tissue plasma membranes, lnsulin analogues with a single amino acid substitution or single N-methylation of the peptide bond in the position B26 were all shortened in the C-terminus of the B-chain by four amino acids. The effect of modifications was followed by the binding to the insulin receptor. From our results, we can deduce several conclusions: (1) the replacement of tyrosine in the position B26 by histidine, [N-MeHis^B26]-des-tetrapeptide-(B27-B30)-insulin-B26-amide and [N-MeGlu^B26]-des-tetrapeptide- (B2-B30)-insulin-B26-amide, have no significant effect on the binding affinity and they show binding affinity 105%, 190% and 208%, respectively, of that of human insulin; (2) [Aad^B26] -des-tetrapeptide-(B27-B30)-insulin-B26-amide and [Phe(4-carboxy^B26)]-des-tetrapeptide- (B27~B30)-insulin-B26-amide affect the potency highly positively in vitro studies; they show binding affinity 529 and 289 %, respectively, of that of human insulin.展开更多
Graphene mesh electrodes (GMEs) with good conductivity and transparency have been fabricated by the standard industrial photolithography and 02 plasma etching process using graphene solutions. Organic photovoltaic ...Graphene mesh electrodes (GMEs) with good conductivity and transparency have been fabricated by the standard industrial photolithography and 02 plasma etching process using graphene solutions. Organic photovoltaic (OPV) cells using GMEs as the transparent electrodes with a blend of poly-(3-hexylthiophene) phenyl-C61-butyric acid methyl ester (P3HT/PC61BM) as the active layer have been fabricated and exhibit a power conversion efficiency (PCE) of 2.04%, the highest PCE for solution-processed graphene transparent electrode-based solar cells reported to date.展开更多
A low band gap acceptor-donor-acceptor (A-D-A) small molecule donor material, named DR3TDTN, has been designed and synthesized for solution-processed organic solar cells. DR3TDTN shows narrow optical band gap with v...A low band gap acceptor-donor-acceptor (A-D-A) small molecule donor material, named DR3TDTN, has been designed and synthesized for solution-processed organic solar cells. DR3TDTN shows narrow optical band gap with value of 1.49 eV and broad absorption spectrum from 300 to 820 rim. The HOMO and LUMO energy levels of DR3TDTN are -4.74 and -3.26 eV, respectively. The optimized photovoltaic device based on DR3TDTN:PC71BM blend film shows a power conversion efficiency of 3.03% with an open-circuit voltage of 0.67 V, a short-circuit current of 8.22 mA·cm^-2 and fill factor of 0.55.展开更多
A novel hybrid material prepared from graphene and poly(3,4-ethyldioxythiophene)(PEDOT)shows excellent transparency,electrical conductivity,and good flexibility,together with high thermal stability and is easily proce...A novel hybrid material prepared from graphene and poly(3,4-ethyldioxythiophene)(PEDOT)shows excellent transparency,electrical conductivity,and good flexibility,together with high thermal stability and is easily processed in both water and organic solvents.Conductivities of the order of 0.2 S/cm and light transmittance of greater than 80%in the 4001800 nm wavelength range were observed for fi lms with thickness of tens of nm.Practical applications in a variety of optoelectronic devices are thus expected for this transparent and flexible conducting graphene-based hybrid material。展开更多
An upconversion luminescence powder TiO2:(Er3+,Yb3+) is prepared by a hydrothermal method and used to fabricate dye-sensitized solar cell (DSSC).The TiO2:(Er3+,Yb3+) powder undergoes upconversion luminescence,converti...An upconversion luminescence powder TiO2:(Er3+,Yb3+) is prepared by a hydrothermal method and used to fabricate dye-sensitized solar cell (DSSC).The TiO2:(Er3+,Yb3+) powder undergoes upconversion luminescence,converting infrared light which the dye can not absorb into visible light with wavelengths of 510-700 nm which the dye can absorb,increasing the photocurrent of the DSSC.TiO2:(Er3+,Yb3+) also acts as a p-type dopant,heightening the Fermi level of the oxide film,which increases the photovoltage of the DSSC.The best performance of the DSSC is found when the ratio of TiO2/luminescence powder is 1/3 in the luminescence layer.Under simulated solar irradiation of 100 mW cm-2 (AM 1.5),the DSSC containing TiO2:(Er3+,Yb3+) doping achieves a light-to-electricity energy conversion efficiency of 7.28% compared with 6.41% for the undoped DSSC.展开更多
Two copper(Ⅱ) coordination polymers {[Cu(bib)(nip)]·1.5 H_(2)O}_(n)(1) and [Cu_(2)(bib)(glu)_(2)]_(n)(2)(bib = 1,4-bis(2-methyl-imidazol-1-yl)butane, H2nip = 5-nitroisophthalic acid, H2glu = glutaric acid) were ...Two copper(Ⅱ) coordination polymers {[Cu(bib)(nip)]·1.5 H_(2)O}_(n)(1) and [Cu_(2)(bib)(glu)_(2)]_(n)(2)(bib = 1,4-bis(2-methyl-imidazol-1-yl)butane, H2nip = 5-nitroisophthalic acid, H2glu = glutaric acid) were synthesized by the hydrothermal method and characterized by single-crystal X-ray diffraction, elemental analyses, IR and solid-state diffuse-reflection spectra. 1 forms a 2D network with the point symbol of(4~4·6^(2)) and 2D → 2D polythreaded network. 2 constructs the 6-connected 3D network based on the [Cu_(2)(COO)_(2)] dimer with the point symbol of(4~4·6~(10)·8). The energy band gaps(Eg) of 1 and 2 were 2.453 and 2.162 eV, respectively. 1 and 2 present high photocatalytic activity for the degradation of methylene blue under visible light irradiation.展开更多
A new strategy to chemically synthesize exchange-coupled SmCo_(5)/Sm_(2) Co_(17) nanocomposites by in situ decomposition of SmCox(5<x<8.5)is reported in this work.Our synthesis starts with the fabrication of Co/...A new strategy to chemically synthesize exchange-coupled SmCo_(5)/Sm_(2) Co_(17) nanocomposites by in situ decomposition of SmCox(5<x<8.5)is reported in this work.Our synthesis starts with the fabrication of Co/Sm_(2) O_(3)(Sm to Co atomic ratio of Sn/Co=1:4.2),which can be reduced into 40-nm SmCo_(5) single crystal nanoparticles by Ca under the protection of CaO,showing a high coercivity of 2.85 T and saturation magnetization(Ms)of 0.0671 A·m^(2)·g^(-1).By changing the Sm/Co to 1:4.5,1:4.8 and 1:5.2,SmCo_(5)/Sm_(2) Co_(17) nanocomposites with different proportions were acquired using the same process.Owing to the in situ decomposition of SmCo_(x) intermediate,the small size(both of their size less than 10 nm)and uniform phase distribution were achieved in our nanocomposites.Thus,the as-prepared nanocomposites display a strong exchange-coupling interaction.As a consequence,SMCo_(5)/Sm_(2)Co_(17)(Sm/Co=1:5.2)exhibits a coercivity of 1.23 T and enhanced M7 T(magnetization at 7 T)of 0.0812 A·m^(2)·g^(-1),increasing by 21%than pure SmCo_(5).Our synthesis provides a new protocol to prepare exchange-coupled high-performance nanocomposites.展开更多
We demonstrate a synaptic transistor that uses a thermally crosslinked three-dimensional network to accommodate ionic liquid to form an ion gel layer. The synaptic transistor successfully emulated important synaptic p...We demonstrate a synaptic transistor that uses a thermally crosslinked three-dimensional network to accommodate ionic liquid to form an ion gel layer. The synaptic transistor successfully emulated important synaptic plasticity, such as paired-pulse facilitation, spike-number dependent plasticity, spike-voltage dependent plasticity, and spike-rate dependent plasticity;these responses imply successful use of the ion gel. Moreover, the device realized “OR” and “AND” logic operations, and high-pass filtering behavior. Energy consumption of the device can be reduced to sub-femtojoule level, which is below that of biological synapses. Compared with traditional physical cross-linking using block copolymers, this method provides a facile strategy to prepare ion gels with tunable properties by altering the polymers and crosslinkers,and to enormously reduce the price by replacing expensive block copolymers or eliminating additional synthesis processes. This report provides a versatile strategy for design of synaptic transistors and their applications in neuromorphic electronics.展开更多
A new zinc coordination polymer{[Zn2(ttmb)2(dca)4(H2O)].H2O}n(1.H2O)was synthesized by the reaction of 1,3,5-tris(1,2,4-triazol-1-ylmethyl)benzene(ttmb),Zn(Ⅱ)salt and sodium dicyanamide(Na(dca)).The structure of the ...A new zinc coordination polymer{[Zn2(ttmb)2(dca)4(H2O)].H2O}n(1.H2O)was synthesized by the reaction of 1,3,5-tris(1,2,4-triazol-1-ylmethyl)benzene(ttmb),Zn(Ⅱ)salt and sodium dicyanamide(Na(dca)).The structure of the title compound was determined by single-crystal X-ray diffraction,elemental analyses and IR spectra.1 exhibits a(3,4)-connected 2D double-layer network with the point symbol of{63}{(66}.The solid-state luminescence shows a strong emission band at 485 nm upon excitation at 384 nm.The thermal stability properties were also studied.展开更多
A divergent intramolecular reaction of phosphine tethered alkyne in protic solvent was developed.This provided a novel and simple access to a large variety of(Z)-alkenylphosphine oxides and phospholane oxides.Our prel...A divergent intramolecular reaction of phosphine tethered alkyne in protic solvent was developed.This provided a novel and simple access to a large variety of(Z)-alkenylphosphine oxides and phospholane oxides.Our preliminary studies suggested that these divergent reactions are closely related to the reaction condition and molecular structure.A possible mechanism of C-P bond cleavage of a pentacoordinated hydroxyphosphorane intermediate was proposed.展开更多
One polythiophene derivative PT3T and two low band gap copolymers,PBTT-T3T and PBTT,with different ratios of 5,6-dini-trobenzothiadiazole as the acceptor unit in the polymer backbone have been synthesized by Pd-cataly...One polythiophene derivative PT3T and two low band gap copolymers,PBTT-T3T and PBTT,with different ratios of 5,6-dini-trobenzothiadiazole as the acceptor unit in the polymer backbone have been synthesized by Pd-catalyzed Stille-coupling polymerizations.Thermal stability,X-ray diffraction analyses,UV-vis absorption spectra,photoluminescence spectra and electrochemical properties of the copolymers were investigated.The band gap estimated from UV-vis-NIR spectra of the copolymers films varied from 1.39 to 1.94 eV.Among these copolymers,the films of PBTT-T3T and PBTT,which contain the 5,6-dinitrobenzothiadiazole unit,cover a broad wavelength range in the visible and near-infrared region from 400 to 1000 nm with the maximal peak absorption around 700 nm,which is exactly matched with the maximum in the photon flux of the sun.展开更多
Different approaches to brominate dialkyl isothianaphthene-5,6-dicarboxylate were tried and single crystals of target molecule and side product were obtained. A planar copolymer with the trans-ethene has been prepared...Different approaches to brominate dialkyl isothianaphthene-5,6-dicarboxylate were tried and single crystals of target molecule and side product were obtained. A planar copolymer with the trans-ethene has been prepared, which shows good solubility in common organic solvents and broad absorption with edge to 967 nm in film.展开更多
A cascade carbonylative ring expansion and [2+2]/[4+2] cycloaddition of strained 1-iminylphosphirane complexes with aryl allenes were reported.The carbonylative ring expansion of 1-iminylphosphirane complexes provides...A cascade carbonylative ring expansion and [2+2]/[4+2] cycloaddition of strained 1-iminylphosphirane complexes with aryl allenes were reported.The carbonylative ring expansion of 1-iminylphosphirane complexes provides an azaphosphacyclohexone complex intermediate with a C=P double bond.The following [2+2] or dearomatic [4+2] cycloaddition of this intermediate with allenes is modulated by the aryl substituents on the imino carbon.The regioselective [2+2] cycloaddition with 1,1-diarylallene provides an entry to bicyclo[4.2.0]octan-4-one skeletons featuring a four-membered phosphacyclobutane moiety.While dearomatic [4+2] cycloaddition was preferred with less aromatic naphthalene and yielded octahydrochrysene skeleton containing heteroatoms.展开更多
A facile access to mono-C-alkynyl-o-carboranes from o-carboranes and arylsulfonylacetylenes was developed.This facile process tolerates a wide variety of functional groups,occurs at mild conditions in onepot procedure...A facile access to mono-C-alkynyl-o-carboranes from o-carboranes and arylsulfonylacetylenes was developed.This facile process tolerates a wide variety of functional groups,occurs at mild conditions in onepot procedure with short reaction time.The obtained mono-C-alkynyl-o-carboranes can be easily derivatized to synthesize 1,2-difunctionalized o-carboranes.This work provides a useful tool for the functionalization of o-carboranes.展开更多
基金supported by“the Key and General research Project of Education Department of Liaoning Province(LJKZ0277)”“Liaoning BaiQianWan Talents Program.”。
文摘Recent studies revealed that the increased level of hypochlorous acid(HOCl)may be deemed to be one of the signs of chronic inflammatory joint disease.Accordingly,the development of effective methods for rapid and accurate detection or monitoring of HOCl in vivo is of great significance for further understanding the role of HOCl in rheumatoid arthritis(RA).Herein,a ratiometric near-infrared(NIR)fluorescent probe(PTA)was reported for the detection and monitoring of HOCl.In the presence of HOCl,the electron-rich S atom and C=C double bond of probe PTA were oxidized in sequence,resulting in the significant hypochromatic shift and decline of absorption spectra.Simultaneously,the intramolecular charge transfer(ICT)process of PTA is inhibited,causing the intrinsic fluorescence emission of PTA shift from 680 to 550 nm.PTA-based test paper strips were successfully prepared and applied to determinate HOCl in actual water samples by“naked eye”colorimetric method.PTA features NIR emission,large Stokes shift(200 nm),low cytotoxicity,high sensitivity(33.9 nM),and short response time(45 s),which enable it to be successfully utilized for imaging endogenous and exogenous HOCl in living zebrafish and mice.More importantly,PTA shows remarkable effectiveness for the monitoring of HOCl-mediated treatment response to RA.Consequently,PTA provides a new approach to further understand the role of HOCl in RA and evaluate the drug treatment efficiency of RA.
基金Supported by the National Natural Science Foundation of China under Grant Nos 60676051, 20644004, and 07JCYBJC03000, the Tianjin Natural Science Foundation (06TXTJJC14603), the National Basic Research Program of China under Grant No 2006CBON0702), the Specialized Research Fund for the Doctoral Programme of Higher Education of China under Grant No 20040055020, and Tianjin Key Laboratory for Photoelectric Materials and Devices.
文摘A novel photovoltaic cell with an active layer of poly(phenyleneethynylene) (PPE)/C60/N,N'-diphenyl-N,N'-di-(m-tolyl)-p-benzidine (TPD) is designed. In the active layer, PPE is the major component; C60 and TPD are the minor ones. Compared with a control BHJ device based on PPE/C60, the short circuit current density Jsc is increased by 1 order of magnitude, and the whole device performance is increased greatly, however the open circuit voltage Voc is largely decreased. The possible mechanism of the improved performance may be as follows: In the PPE/C60/TPD device, PPE, C60, and TPD serve as the energy harvesting material, the electron transport material, and the hole transport material, respectively. As the TPD and C60 are spatially separated by PPE, the charge recombination is effectively retarded.
文摘The positively charged single walled carbon nanotubes (SWNTs^+) were prepared by conjugating with -CONH-C6H12-NH3^+. The double strand DNA (dsDNA) chains were loaded onto SWNTs^+ via the electrostatic interactions. SWNTs^+ shows improved loading efficiency (353.5 μg/mg) toward dsDNA compared with that of charged free single walled carbon nanotubes (SWNTs) (82.9 μg/mg).
基金financial support from the National Natural Science Foundation of China (No.21601076)the Natural Science Foundation of Liaoning Province (No.2019-ZD0266)。
文摘Efficient bifunctional OER/ORR catalysts are crucial for the further development of zinc-air battery. From a sustainable point of view, it is important that electrocatalysts are efficient, low cost, and composed of abundant resources instead of scarce metals. Due to their good conductivity, low cost, and strong durability, carbon-based materials are considered a promising alternative in the field of commercial zinc-air battery catalysts. Herein, we briefly introduce the zinc-air battery and then summarize recent progress in the development of carbon-based bifunctional catalysts by defect engineering, heteroatom doping and metal doping. Finally, we discuss the main challenges and prospects for the future development of carbon-based bifunctional oxygen catalysts.
基金supported by the National High Technology Research and Development Program of China (863 Program) (No. SQ2008AA03Z2470974)the National Natural Science Foundation of China (Nos. 50572030 and 50372022)the Young Talent Program of Fujian Province (No. 2007F3060)
文摘A new 1D coordination polymer [Co(bpp)3Cl2(H2O)2]n 1 (bpp = 1,3-bis(4-pyridyl)-propane) was synthesized and characterized by elemental analysis,IR spectrum and single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system,space group Ibca with a = 16.569(9),b = 17.240(10),c = 27.087(16) ,V = 7738(8) 3,Z = 8,Dc = 1.306 g/cm3,Mr = 760.65,λ(MoKa) = 0.71073 ,μ = 0.623 mm1,F(000) = 3192,the final R = 0.0678 and wR = 0.2011. The Co(II) atom is coordinated in a slightly distorted octahedral CoN4Cl2 geometry by two Cl atoms in the axial positions,four N atoms from the two bridging bpp ligands and two pendant bpp ligands. The CoN4Cl2 octahedra are connected by the bridging bpp ligands to form a 1D neutral coordination polymer chain. The chains are linked by face-to-face π-π interactions between adjacent pendant bpp ligands to give rise to a 3D supramolecular architecture. The photoluminescent investigation indicates that the emission of 1 is attributed to ligand-centered emission. The variable-temperature magnetic susceptibility measurement shows weak antiferromagnetic behavior in the coπmplex.
基金supported by the National Natural Science Foundation of China (Nos. 50572030 and 50372022)the Research Fund of Huaqiao University (No. 06BS216)the Young Talent Program of Fujian Province (No. 2007F3060)
文摘A new mononuclear Cu(Ⅱ) dithiocarbamate complex CuI(prdtc)(phen) 1 (prdtc = N-pyrrolidinyldithiocarbamate, phen = 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 8.7110(9), b = 14.7143(14), c = 14.8507(15) A, β = 109.721(6)°, V = 1791.9(3) A3, Z = 4, Dc = 1.916 g/cm3, CI7H16CulN3S2, Mr = 516.89, λ(MoKa) = 0.71073A,μ = 3.178 mm^-1, F(000) = 1012, the final R = 0.0369 and wR = 0.0987. A total of 4082 unique reflections were collected, of which 2916 with I 〉 2σ(I) were observed. The Cu(Ⅱ) atom is five-coordinated in a distorted square-pyramidal geometry by one I atom in the apical position, two S atoms from a prdtc ligand and two N atoms from a phen ligand in the basal plane. There exist face-to-face aromatic π-π stacking interactions between adjacent phen ligands stabilizing the structure and making the complex assemble into a 1D structure along the a axis. It can be concluded that the difference of the dtc flexibility and reaction conditions result in the structural difference between complex 1 and CuI(dmdtc)(phen) (dmdtc = N, N-dimethyldithiocarbamate).
文摘The role of three highly conserved insulin residues Tyr^B26 was studied to better understand the relationship between insulin and receptor from rat adipose tissue plasma membranes, lnsulin analogues with a single amino acid substitution or single N-methylation of the peptide bond in the position B26 were all shortened in the C-terminus of the B-chain by four amino acids. The effect of modifications was followed by the binding to the insulin receptor. From our results, we can deduce several conclusions: (1) the replacement of tyrosine in the position B26 by histidine, [N-MeHis^B26]-des-tetrapeptide-(B27-B30)-insulin-B26-amide and [N-MeGlu^B26]-des-tetrapeptide- (B2-B30)-insulin-B26-amide, have no significant effect on the binding affinity and they show binding affinity 105%, 190% and 208%, respectively, of that of human insulin; (2) [Aad^B26] -des-tetrapeptide-(B27-B30)-insulin-B26-amide and [Phe(4-carboxy^B26)]-des-tetrapeptide- (B27~B30)-insulin-B26-amide affect the potency highly positively in vitro studies; they show binding affinity 529 and 289 %, respectively, of that of human insulin.
文摘Graphene mesh electrodes (GMEs) with good conductivity and transparency have been fabricated by the standard industrial photolithography and 02 plasma etching process using graphene solutions. Organic photovoltaic (OPV) cells using GMEs as the transparent electrodes with a blend of poly-(3-hexylthiophene) phenyl-C61-butyric acid methyl ester (P3HT/PC61BM) as the active layer have been fabricated and exhibit a power conversion efficiency (PCE) of 2.04%, the highest PCE for solution-processed graphene transparent electrode-based solar cells reported to date.
文摘A low band gap acceptor-donor-acceptor (A-D-A) small molecule donor material, named DR3TDTN, has been designed and synthesized for solution-processed organic solar cells. DR3TDTN shows narrow optical band gap with value of 1.49 eV and broad absorption spectrum from 300 to 820 rim. The HOMO and LUMO energy levels of DR3TDTN are -4.74 and -3.26 eV, respectively. The optimized photovoltaic device based on DR3TDTN:PC71BM blend film shows a power conversion efficiency of 3.03% with an open-circuit voltage of 0.67 V, a short-circuit current of 8.22 mA·cm^-2 and fill factor of 0.55.
基金the financial support from the Natural Science Foundation of china(NSFC)(#20774047)the Ministry of Science and Techology of china(MoST)(#2006CB932702)natural Science Foundation(NSF)of Tianjin City(#07JCYBJC03000,#08JCZDJC25300).
文摘A novel hybrid material prepared from graphene and poly(3,4-ethyldioxythiophene)(PEDOT)shows excellent transparency,electrical conductivity,and good flexibility,together with high thermal stability and is easily processed in both water and organic solvents.Conductivities of the order of 0.2 S/cm and light transmittance of greater than 80%in the 4001800 nm wavelength range were observed for fi lms with thickness of tens of nm.Practical applications in a variety of optoelectronic devices are thus expected for this transparent and flexible conducting graphene-based hybrid material。
基金supported by the National High Technology Research and Development Program of China (2009AA03Z217)the National Natural Science Foundation of China (90922028,50842027)
文摘An upconversion luminescence powder TiO2:(Er3+,Yb3+) is prepared by a hydrothermal method and used to fabricate dye-sensitized solar cell (DSSC).The TiO2:(Er3+,Yb3+) powder undergoes upconversion luminescence,converting infrared light which the dye can not absorb into visible light with wavelengths of 510-700 nm which the dye can absorb,increasing the photocurrent of the DSSC.TiO2:(Er3+,Yb3+) also acts as a p-type dopant,heightening the Fermi level of the oxide film,which increases the photovoltage of the DSSC.The best performance of the DSSC is found when the ratio of TiO2/luminescence powder is 1/3 in the luminescence layer.Under simulated solar irradiation of 100 mW cm-2 (AM 1.5),the DSSC containing TiO2:(Er3+,Yb3+) doping achieves a light-to-electricity energy conversion efficiency of 7.28% compared with 6.41% for the undoped DSSC.
基金supported by the Natural Science Foundation of Jiangsu Province(No.BK20161212)the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe project of scientific and technological infrastructure of Suzhou(SZS201905)。
文摘Two copper(Ⅱ) coordination polymers {[Cu(bib)(nip)]·1.5 H_(2)O}_(n)(1) and [Cu_(2)(bib)(glu)_(2)]_(n)(2)(bib = 1,4-bis(2-methyl-imidazol-1-yl)butane, H2nip = 5-nitroisophthalic acid, H2glu = glutaric acid) were synthesized by the hydrothermal method and characterized by single-crystal X-ray diffraction, elemental analyses, IR and solid-state diffuse-reflection spectra. 1 forms a 2D network with the point symbol of(4~4·6^(2)) and 2D → 2D polythreaded network. 2 constructs the 6-connected 3D network based on the [Cu_(2)(COO)_(2)] dimer with the point symbol of(4~4·6~(10)·8). The energy band gaps(Eg) of 1 and 2 were 2.453 and 2.162 eV, respectively. 1 and 2 present high photocatalytic activity for the degradation of methylene blue under visible light irradiation.
基金This study was financially supported by the National Natural Science Foundation of China(No.51701109)the Natural Science Foundation of Beijing Municipality,China(No.2192007)+1 种基金the China Postdoctoral Science Foundation(No.2018M641132)Leshan Normal University Research Program,China(No.LZD021).
文摘A new strategy to chemically synthesize exchange-coupled SmCo_(5)/Sm_(2) Co_(17) nanocomposites by in situ decomposition of SmCox(5<x<8.5)is reported in this work.Our synthesis starts with the fabrication of Co/Sm_(2) O_(3)(Sm to Co atomic ratio of Sn/Co=1:4.2),which can be reduced into 40-nm SmCo_(5) single crystal nanoparticles by Ca under the protection of CaO,showing a high coercivity of 2.85 T and saturation magnetization(Ms)of 0.0671 A·m^(2)·g^(-1).By changing the Sm/Co to 1:4.5,1:4.8 and 1:5.2,SmCo_(5)/Sm_(2) Co_(17) nanocomposites with different proportions were acquired using the same process.Owing to the in situ decomposition of SmCo_(x) intermediate,the small size(both of their size less than 10 nm)and uniform phase distribution were achieved in our nanocomposites.Thus,the as-prepared nanocomposites display a strong exchange-coupling interaction.As a consequence,SMCo_(5)/Sm_(2)Co_(17)(Sm/Co=1:5.2)exhibits a coercivity of 1.23 T and enhanced M7 T(magnetization at 7 T)of 0.0812 A·m^(2)·g^(-1),increasing by 21%than pure SmCo_(5).Our synthesis provides a new protocol to prepare exchange-coupled high-performance nanocomposites.
基金financial support from the National Natural Science Foundation of China(No.21601076)the Natural Science Foundation of Liaoning Province(No.2019-ZD0266)。
文摘We demonstrate a synaptic transistor that uses a thermally crosslinked three-dimensional network to accommodate ionic liquid to form an ion gel layer. The synaptic transistor successfully emulated important synaptic plasticity, such as paired-pulse facilitation, spike-number dependent plasticity, spike-voltage dependent plasticity, and spike-rate dependent plasticity;these responses imply successful use of the ion gel. Moreover, the device realized “OR” and “AND” logic operations, and high-pass filtering behavior. Energy consumption of the device can be reduced to sub-femtojoule level, which is below that of biological synapses. Compared with traditional physical cross-linking using block copolymers, this method provides a facile strategy to prepare ion gels with tunable properties by altering the polymers and crosslinkers,and to enormously reduce the price by replacing expensive block copolymers or eliminating additional synthesis processes. This report provides a versatile strategy for design of synaptic transistors and their applications in neuromorphic electronics.
基金the Natural Science Foundation of Jiangsu Province(No.BK20161212)the Priority Academic Program Development of Jiangsu Higher Education Institutionsthe project of Scientific and Technological Infrastructure of Suzhou(SZS201905)。
文摘A new zinc coordination polymer{[Zn2(ttmb)2(dca)4(H2O)].H2O}n(1.H2O)was synthesized by the reaction of 1,3,5-tris(1,2,4-triazol-1-ylmethyl)benzene(ttmb),Zn(Ⅱ)salt and sodium dicyanamide(Na(dca)).The structure of the title compound was determined by single-crystal X-ray diffraction,elemental analyses and IR spectra.1 exhibits a(3,4)-connected 2D double-layer network with the point symbol of{63}{(66}.The solid-state luminescence shows a strong emission band at 485 nm upon excitation at 384 nm.The thermal stability properties were also studied.
基金National Natural Science Foundation of China(Nos.21672193,21272218)Henan Province postdoctoral research start-up projectZhengzhou University of China for financial support of this research。
文摘A divergent intramolecular reaction of phosphine tethered alkyne in protic solvent was developed.This provided a novel and simple access to a large variety of(Z)-alkenylphosphine oxides and phospholane oxides.Our preliminary studies suggested that these divergent reactions are closely related to the reaction condition and molecular structure.A possible mechanism of C-P bond cleavage of a pentacoordinated hydroxyphosphorane intermediate was proposed.
基金support from the National Natural Science Foundation of China (50933003 & 50903044)MOST of China (2009AA032304)
文摘One polythiophene derivative PT3T and two low band gap copolymers,PBTT-T3T and PBTT,with different ratios of 5,6-dini-trobenzothiadiazole as the acceptor unit in the polymer backbone have been synthesized by Pd-catalyzed Stille-coupling polymerizations.Thermal stability,X-ray diffraction analyses,UV-vis absorption spectra,photoluminescence spectra and electrochemical properties of the copolymers were investigated.The band gap estimated from UV-vis-NIR spectra of the copolymers films varied from 1.39 to 1.94 eV.Among these copolymers,the films of PBTT-T3T and PBTT,which contain the 5,6-dinitrobenzothiadiazole unit,cover a broad wavelength range in the visible and near-infrared region from 400 to 1000 nm with the maximal peak absorption around 700 nm,which is exactly matched with the maximum in the photon flux of the sun.
文摘Different approaches to brominate dialkyl isothianaphthene-5,6-dicarboxylate were tried and single crystals of target molecule and side product were obtained. A planar copolymer with the trans-ethene has been prepared, which shows good solubility in common organic solvents and broad absorption with edge to 967 nm in film.
基金supported by the National Natural Science Foundation of China(Nos.21302174,21672193 and 21272218)China Post-doctoral Science Foundation(No.2017M622362)+1 种基金Ministry of Industry and Information Technology of the People's Republic of China(No.Z135060009002)Key Research Projects of Universities in Henan Province(No.20A150040)。
文摘A cascade carbonylative ring expansion and [2+2]/[4+2] cycloaddition of strained 1-iminylphosphirane complexes with aryl allenes were reported.The carbonylative ring expansion of 1-iminylphosphirane complexes provides an azaphosphacyclohexone complex intermediate with a C=P double bond.The following [2+2] or dearomatic [4+2] cycloaddition of this intermediate with allenes is modulated by the aryl substituents on the imino carbon.The regioselective [2+2] cycloaddition with 1,1-diarylallene provides an entry to bicyclo[4.2.0]octan-4-one skeletons featuring a four-membered phosphacyclobutane moiety.While dearomatic [4+2] cycloaddition was preferred with less aromatic naphthalene and yielded octahydrochrysene skeleton containing heteroatoms.
基金financial support from the National Natural Science Foundation of China(Nos.21672193,21272218)the Key Scientific and Technological Project of Henan Province(No.202102310327)+3 种基金the Ministry of Industry and Information Technology(No.Z135060009002)the Postdoctoral Research Grant in Henan Province(No.001803004)the Programme of Introducing Talents of Discipline to Universities(111 Project,No.D20003)Zhengzhou University of China。
文摘A facile access to mono-C-alkynyl-o-carboranes from o-carboranes and arylsulfonylacetylenes was developed.This facile process tolerates a wide variety of functional groups,occurs at mild conditions in onepot procedure with short reaction time.The obtained mono-C-alkynyl-o-carboranes can be easily derivatized to synthesize 1,2-difunctionalized o-carboranes.This work provides a useful tool for the functionalization of o-carboranes.