The treatment of bis(2-hydroxybenzyl)-amine(HL) with NaOH and Co(Ⅱ)(NO) 2 gives isostructural one-dimensional coordination polymers [(NaOC2H5)CoL2]n(1). The cobalt ions have an octahedral geometry and are coordinate...The treatment of bis(2-hydroxybenzyl)-amine(HL) with NaOH and Co(Ⅱ)(NO) 2 gives isostructural one-dimensional coordination polymers [(NaOC2H5)CoL2]n(1). The cobalt ions have an octahedral geometry and are coordinated by two crystallographically independent ligands which are further linked by μ -O\-\{phenol\} bridged Co and Na atoms to give a one-dimentional structure.展开更多
Controlling charge polarity in the semiconducting single-walled carbon nanotubes(CNTs) by substitutional doping is a difficult work due to their extremely strong C–C bonding. In this work, an inner doping strategy is...Controlling charge polarity in the semiconducting single-walled carbon nanotubes(CNTs) by substitutional doping is a difficult work due to their extremely strong C–C bonding. In this work, an inner doping strategy is explored by filling CNTs with one-dimensional(1D)-TM_(6)Te_(6) nanowires to form TM_(6)Te_(6)@CNT-(16,0) 1D van der Waals heterostructures(1D-vd WHs). The systematic first-principles studies on the electronic properties of 1D-vd WHs show that N-type doping CNTs can be formed by charge transfer from TM_(6)Te_(6) nanowires to CNTs, without introducing additional carrier scattering.Particularly, contribution from both T M(e.g., Sc and Y) and Te atoms strengthens the charge transfer. The outside CNTs further confine the dispersion of Te-p orbitals in nanowires that deforms the C-π states at the bottom of the conduction band to quasi sp^(3) hybridization. Our study provides an inner doping strategy that can effectively confine the charge polarity of CNTs and further broaden its applications in some novel nano-devices.展开更多
A new type of phosphor Sr2ZrO4 with one-dimensional structure was prepared bysolid reaction and its luminescence is seen at room temperature. The excitation and emissionspectra were measured and display broad maximum ...A new type of phosphor Sr2ZrO4 with one-dimensional structure was prepared bysolid reaction and its luminescence is seen at room temperature. The excitation and emissionspectra were measured and display broad maximum at 354 nm and 386 nm respectively. Themechanism of this luminescence is ascribed to charge transfer.展开更多
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'...Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6.展开更多
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ...To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced.展开更多
The fabrication of a new type of one-dimensional Au-Ag porous nanotube（NPT） structure was presented based on a facile combination of nanocrystal growth and surface modification.Ag nanowires with various diameters we...The fabrication of a new type of one-dimensional Au-Ag porous nanotube（NPT） structure was presented based on a facile combination of nanocrystal growth and surface modification.Ag nanowires with various diameters were firstly served as the chemical plating templates via a polyol-process.Then,one-dimensional（1D） Au-Ag porous nanostructures with tailored structural features could be prepared by controlling the individual steps involved in this process,such as nanowire growth,surface modification,thermal diffusion,and dealloying.Structural characterizations reveal these Au-Ag porous nanotubes,non-porous nanotubes and porous nanowires possess novel nano-architectures with multimodal open porosity and excellent structural continuity and integrity,which make them particularly desirable as novel 1D nanocarriers for biomedical,drug delivery and sensing applications.展开更多
Alkali-free SiO_(2)-Al_(2)O_(3)-CaO-MgO with different SiO_(2)/Al_(2)O_(3)mass ratios was prepared by conventional melt quenching method.The glass network structure,thermodynamic properties and elastic modulus changes...Alkali-free SiO_(2)-Al_(2)O_(3)-CaO-MgO with different SiO_(2)/Al_(2)O_(3)mass ratios was prepared by conventional melt quenching method.The glass network structure,thermodynamic properties and elastic modulus changes with SiO_(2)and Al_(2)O_(3)ratios were investigated using various techniques.It is found that when SiO_(2)is replaced by Al_(2)O_(3),the Q^(4) to Q^(3) transition of silicon-oxygen network decreases while the aluminum-oxygen network increases,which result in the transformation of Si-O-Si bonds to Si-O-Al bonds and an increase in glass network connectivity even though the intermolecular bond strength decreases.The glass transition temperature(T_(g))increases continuously,while the thermal expansion coefficient increases and high-temperature viscosity first decreases and then increases.Meanwhile,the elastic modulus values increase from 93 to 102 GPa.This indicates that the elastic modulus is mainly affected by packing factor and dissociation energy,and elements with higher packing factors and dissociation energies supplant those with lower values,resulting in increased rigidity within the glass.展开更多
To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with g...To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with graphene oxide(GO).The micro-pore structure of GOPM is characterized using LF-NMR and SEM.Fractal theory is applied to calculate the fractal dimension of pore volume,and the deterioration patterns are analyzed based on the evolution characteristics of capillary pores.The experimental results indicate that,after 25 salt-freeze-thaw cycles(SFTc),SO2-4 ions penetrate the matrix,generating corrosion products that fill existing pores and enhance the compactness of the specimen.As the number of cycles increases,the ongoing formation and expansion of corrosion products within the matrix,combined with persistent freezing forces,and result in the degradation of the pore structure.Therefore,the mass loss rate(MLR)of the specimens shows a trend of first decreasing and then increasing,while the relative dynamic elastic modulus(RDEM)initially increases and then decreases.Compared to the PC group specimens,the G3PM group specimens show a 28.71% reduction in MLR and a 31.42% increase in RDEM after 150 SFTc.The fractal dimensions of the transition pores,capillary pores,and macropores in the G3PM specimens first increase and then decrease as the number of SFTc increases.Among them,the capillary pores show the highest correlation with MLR and RDEM,with correlation coefficients of 0.97438 and 0.98555,respectively.展开更多
Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is p...Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality.展开更多
AIM:To investigate the effects of shortening the duration of silicone oil tamponade on retinal structure and function in patients undergoing silicone oil removal(SOR)after surgery for primary rhegmatogenous retinal de...AIM:To investigate the effects of shortening the duration of silicone oil tamponade on retinal structure and function in patients undergoing silicone oil removal(SOR)after surgery for primary rhegmatogenous retinal detachment(RRD).METHODS:A total of 58 eligible patients were enrolled and randomly assigned to two groups based on tamponade duration:the short-term group(30-45d)and the conventional group(≥90d).Comprehensive evaluations were performed before and after SOR,including slitlamp examination,best-corrected visual acuity(BCVA)measurement,intraocular pressure(IOP)testing,optical coherence tomography(OCT),optical coherence tomography angiography(OCTA),microperimetry,electroretinography(ERG),and visual evoked potential(VEP)assessment.RESULTS:A total of 33 patients(23 males and 10 females;33 eyes)were enrolled in the short-term SO tamponade group with mean age of 52.45±9.35y,and 25 patients(15 males and 10 females;25 eyes)were enrolled in the conventional SO tamponade group with mean age of 50.80±12.06y.Compared with the conventional group,the short-term silicone oil tamponade group had a significantly lower incidence of silicone oil emulsification and cataract progression,with no significant difference in retinal reattachment success rate.Structurally,short-term tamponade was associated with increased thickness of the retinal ganglion cell layer(RGCL)in the nasal and superior macular regions and improved recovery of superficial retinal vascular density in these areas.Functionally,the shortterm group showed better BCVA and retinal sensitivity both before and 1mo after SOR;additionally,the P100 amplitude in VEP tests was significantly increased in this group.CONCLUSION:Shortening the duration of silicone oil tamponade effectively reduces damage to retinal structure and function without compromising the success rate of retinal reattachment in patients with primary RRD.展开更多
A one-dimensional chain chlorodibenzyltin 2-quininate has been synthesized and characterized by IR, NMR spectra and elemental analysis. The crystal structure has been determined by X-ray diffraction. The crystal belon...A one-dimensional chain chlorodibenzyltin 2-quininate has been synthesized and characterized by IR, NMR spectra and elemental analysis. The crystal structure has been determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group I4（—） with a = 19.1171（10）, b = 19.1171（10）, c = 12.5158（6） , Z = 8, V = 4574.1（4） 3, Dc = 1.477 g·cm-3, μ（MoKα） = 1.252 mm-1, F（000） = 2032, R = 0.0259 and wR = 0.0723. In the complex, the tin atom is six-coordinated to adopt a distorted octahedral configuration with bridging carboxyl of quinoline-2-carboxylic acid. The result of fluorescence spectrum analysis shows that the title complex at room temperature exhibits an intense photoluminescence with maximum emission at 364.2 nm （λex = 303.0 nm）.展开更多
A new metal-organic coordination polymer [Zn（ipt）（im）2]2n·3nH2O 1 has been obtained by using hydrothermal synthesis and characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-...A new metal-organic coordination polymer [Zn（ipt）（im）2]2n·3nH2O 1 has been obtained by using hydrothermal synthesis and characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P2（1/n） with a = 10.653（3）, b = 17.891（6）, c = 10.743（4）A^°,β= 117.093（5）°, V= 1822.9（10） A^°3, Mr= 413.65, Dc = 1.507 g/cm^3,/t（MoKa） = 1.390 mm^-1, F（000） = 840, Z = 4, the final R = 0.0444 and wR = 0.1066 for 2434 observed reflections （I〉 2σ（I））. Furthermore, compound 1 shows blue photoluminescent property at room temperature.展开更多
One-dimensional Cd S@TiO_2 core-shell heterostructures were fabricated via the hydrolysis of tetrabutyl titanate(TBT) on preformed Cd S nanowires. The as-prepared products were characterized by X-ray diffraction, tran...One-dimensional Cd S@TiO_2 core-shell heterostructures were fabricated via the hydrolysis of tetrabutyl titanate(TBT) on preformed Cd S nanowires. The as-prepared products were characterized by X-ray diffraction, transmission electron microscopy, selected area electron diffraction and diffuse reflectance spectroscopy techniques. Results demonstrated that the hydrolysis of TBT had a great influence on the morphology of the coated TiO_2 shell, resulting in the formation of TiO_2 nanoparticles and nanolayer-modified Cd S@TiO_2 heterostructures. Degradation of methylene blue using Cd S@TiO_2 core-shell heterostructures as photocatalysts under visible light irradiation was investigated. Comparative photocatalytic tests showed that the TiO_2 nanoparticles-modified heterostructure exhibited a superior activity due to the passivity of photogenerated charge carriers.展开更多
A one-dimensional chain coordination polymer [Cu（phen）（2,4,6-TMBA）2（H2O）]n has been synthesized by reacting 2,4,6-trimethyl-benzoic acid, 1,10-phenanthroline and Cu（Ⅱ） perchlorate and its structure was charac...A one-dimensional chain coordination polymer [Cu（phen）（2,4,6-TMBA）2（H2O）]n has been synthesized by reacting 2,4,6-trimethyl-benzoic acid, 1,10-phenanthroline and Cu（Ⅱ） perchlorate and its structure was characterized. Crystal data for this complex： tetragonal, space group I41, a = 2.0293（3）, b = 2.0293（3）, c = 1.3758（2） nm, α =β= γ = 90°, V= 5.6657（13） nm3, Dc= 1.379 g/cm3, Z = 8, μ（MoKa） = 0.815 mm-1, Mr = 588.14, F（000） = 2456, S = 1.047, R = 0.0459 and wR = 0.1053. The crystal structure shows that two neighboring Cu（Ⅱ） ions are linked together by one bridging-chelating 2,4,6-trimethyl-benzoic group, forming a one-dimensional chain structure. Each Cu（Ⅱ） ion is coordinated with two nitrogen atoms from one 1,10-phenanthroline molecule, three oxygen atoms from three 2,4,6-trimethyl-benzoic acid molecules and one oxygen atom from one water molecule, giving a six-coordinate distorted octahedral coordination geometry. The cyclic voltammetry behavior of the complex was also investigated.展开更多
A new cadmium（Ⅱ） polymer [Cd（tdc）（Phen）]n 1 （H2tdc = thiophene-3,4-dicar-boxylic acid, Phen = 1,10-phenanthroline） was synthesized under hydrothermal conditions. The compound crystallizes in the triclinic sys...A new cadmium（Ⅱ） polymer [Cd（tdc）（Phen）]n 1 （H2tdc = thiophene-3,4-dicar-boxylic acid, Phen = 1,10-phenanthroline） was synthesized under hydrothermal conditions. The compound crystallizes in the triclinic system, space group P , with a = 7.3150（10）, b = 10.3598（14）, c = 10.8784（15） , α = 82.2740（10）, β = 72.9730（10）, γ = 80.236（2）°, V = 773.68（18） 3, Z = 2, Mr = 462.74, Dc = 1.986 Mg/m3, μ = 1.58 mm-1, F（000） = 456, the final R = 0.0218 and wR = 0.0465 for 3361 observed reflections with Ⅰ 〉 2σ（Ⅰ）. The compound presents a one-dimensional （1-D） double-stranded structure and exhibits fluorescent emission at room temperature. Furthermore, infrared spectroscopy, elemental analyses, thermogravimetric analysis and powder X-ray diffraction properties of the compound are also investigated.展开更多
A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi...A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi-functionality into a single system, the utilization of hetero-, core/shell and hierarchical nanostructures has become the key issue for building such devices. ZnS, due to its direct wide bandgap, high index of refraction, high transparency in the visible range and intrinsic polarity, is one of the most useful semiconductors for a wide range of electronics applications. This article provides a dense review of the state-of-the-art research activities in one-dimensional （1D） ZnS-based hetero-, core/shell and hierarchical nanostructures. The particular emphasis is put on their syntheses and applications.展开更多
A metal-organic coordination polymer [Cd（bpy）（BDC）]n·nbpy （bpy = 2,2-bipyri-dine, H2BDC = terephthalic acid） has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spec...A metal-organic coordination polymer [Cd（bpy）（BDC）]n·nbpy （bpy = 2,2-bipyri-dine, H2BDC = terephthalic acid） has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group C2/c with a = 15.723（5）, b = 21.695（5）, c = 7.576（5） A, β = 116.171（7）°, V = 2319.3（18）A^3, C28H20CdN4O4, Mr = 588.88, Dc = 1.686 g/cm^3, μ（MoKα） = 0.987 mm^-1, F（000） = 1184, Z = 4, the final R = 0.0464 and wR = 0.0831 for 1882 observed reflections （Ⅰ〉 2σ（Ⅰ））. It exhibits a three-dimensional network with channels constructed from one-dimensional coordination chains via C–H…O hydrogen bonds and significant aromatic π-π stacking interactions.展开更多
A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The compound { [Cu2（C2O4）2（inta）4]（i...A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The compound { [Cu2（C2O4）2（inta）4]（inta）}n 1 crystallizes in the triclinic system, space group P1, with a = 8.4722（5）, b = 10.9825（6）, c = 11.6128（6）A, α= 104.8050（10）,β = 102.5740（10）, γ= 109.6890（10）°, V= 927.18（9） A3, Mr = 929.79, Z = 1, Dc = 1.665 g/cm^3, F（000） = 475, μ = 1.231 mm^-1, R = 0.0453 and wR = 0.1185 for 3290 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Of the compound, the Cu center is octahedrally coordinated with oxalate acting as a tetra-dentate ligand coordinated to the copper atom and each inta serving as a terminal ligand by employing only one N-donor to coordinate with the Cu center. An infinite {Cu2（C2O4）2}∞ chain is formed along the c axis. Furthermore, the 1D chains are held together via extensive hydrogen-bonding interactions to generate a three-dimensional network with 1D channels （ca. 5.491A×11.507A） where inta molecules are filled.展开更多
A one-dimensional chain cobalt（Ⅱ） coordination polymer with 2,4,6-trimethyl- benzoic acid, 4,4′-bipyridine and cobalt perchlorate anhydrous has been synthesized and characterized in the mixture solvent of water an...A one-dimensional chain cobalt（Ⅱ） coordination polymer with 2,4,6-trimethyl- benzoic acid, 4,4′-bipyridine and cobalt perchlorate anhydrous has been synthesized and characterized in the mixture solvent of water and alcohol. Crystal data for this complex： monoclinic, space group C2/c, a = 2.3805（8）, b = 1.1464（4）, c = 1.5807（5） nm, y = 128.435（4）°, V= 3.3791（18） nm^3, Dc = 1.246 g/cm^3, Z = 4, F（000） = 1340, final GooF = 1.009, R = 0.0504 and wR = 0.1287. Structural analysis shows that the cobalt ion is coordinated with two nitrogen atoms of one 4,4′- bipyridine molecule and four oxygen atoms from two 2,4,6-trimethylbenzoic acid molecules and two alcohol molecules, giving a distorted octahedral coordination geometry. The result of TG analysis indicates that the title complex is stable till 200 ℃.展开更多
A new one-dimensional Mg（Ⅱ） coordination polymer, [Mg（L）（phen）（H2O）]（1）, has been hydrothermally synthesized by using 3,5-dinitro-salicylic acid（H2L） and 1,10-phenanthroline（phen）. It crystallizes in mo...A new one-dimensional Mg（Ⅱ） coordination polymer, [Mg（L）（phen）（H2O）]（1）, has been hydrothermally synthesized by using 3,5-dinitro-salicylic acid（H2L） and 1,10-phenanthroline（phen）. It crystallizes in monoclinic, space group C2/c with a = 33.038（7）, b = 6.6481（13）, c = 22.750（5） A, β = 126.99（3）°, V = 3991.1（14） A3, Z = 8, C19H12 MgN4O8, Mr = 448.64, Dc = 1.493 g/cm3, F（000） = 1840, μ（Mo Ka） = 0.146 mm-1, R = 0.0559 and w R = 0.0975. In 1, each L anion bridges two Mg（Ⅱ） atoms to give one-dimensional zigzag chains with the Mg…Mg separation of 5.34 ？, which are extended by π-π stacking interactions between 1,10-phenanthroline ligands into a two-dimensional supramolecular layer. Moreover, the O–H…O hydrogen-bonding interactions further stabilize the layer structure of 1. The luminescent property was also studied for 1 in solid state at room temperature. In addition, natural bond orbital（NBO） analysis was performed by the B3LYP/LANL2 DZ method in Gaussian 09 Program. The calculation results show obvious covalent interaction between the coordinated atoms and Mg（Ⅱ） ion.展开更多
基金Supported by the NationalNaturalScience Foundation of China( No.2 0 1710 2 6 ) and Tianjin Natural Science Founda-tion( No.0 136 0 5 811)
文摘The treatment of bis(2-hydroxybenzyl)-amine(HL) with NaOH and Co(Ⅱ)(NO) 2 gives isostructural one-dimensional coordination polymers [(NaOC2H5)CoL2]n(1). The cobalt ions have an octahedral geometry and are coordinated by two crystallographically independent ligands which are further linked by μ -O\-\{phenol\} bridged Co and Na atoms to give a one-dimentional structure.
基金Project supported by the National Natural Science Foundation of China (Grant No. 92477205)。
文摘Controlling charge polarity in the semiconducting single-walled carbon nanotubes(CNTs) by substitutional doping is a difficult work due to their extremely strong C–C bonding. In this work, an inner doping strategy is explored by filling CNTs with one-dimensional(1D)-TM_(6)Te_(6) nanowires to form TM_(6)Te_(6)@CNT-(16,0) 1D van der Waals heterostructures(1D-vd WHs). The systematic first-principles studies on the electronic properties of 1D-vd WHs show that N-type doping CNTs can be formed by charge transfer from TM_(6)Te_(6) nanowires to CNTs, without introducing additional carrier scattering.Particularly, contribution from both T M(e.g., Sc and Y) and Te atoms strengthens the charge transfer. The outside CNTs further confine the dispersion of Te-p orbitals in nanowires that deforms the C-π states at the bottom of the conduction band to quasi sp^(3) hybridization. Our study provides an inner doping strategy that can effectively confine the charge polarity of CNTs and further broaden its applications in some novel nano-devices.
文摘A new type of phosphor Sr2ZrO4 with one-dimensional structure was prepared bysolid reaction and its luminescence is seen at room temperature. The excitation and emissionspectra were measured and display broad maximum at 354 nm and 386 nm respectively. Themechanism of this luminescence is ascribed to charge transfer.
文摘Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6.
基金Supported by the Science and Technology Cooperation and Exchange special project of Cooperation of Shanxi Province(202404041101014)the Fundamental Research Program of Shanxi Province(202403021212333)+3 种基金the Joint Funds of the National Natural Science Foundation of China(U24A20555)the Lvliang Key R&D of University-Local Cooperation(2023XDHZ10)the Initiation Fund for Doctoral Research of Taiyuan University of Science and Technology(20242026)the Outstanding Doctor Funding Award of Shanxi Province(20242080).
文摘To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced.
基金Project (2012CB932800) supported by the National Basic Research Program of ChinaProject (2012M521330) supported by China Postdoctoral Science Foundation
文摘The fabrication of a new type of one-dimensional Au-Ag porous nanotube（NPT） structure was presented based on a facile combination of nanocrystal growth and surface modification.Ag nanowires with various diameters were firstly served as the chemical plating templates via a polyol-process.Then,one-dimensional（1D） Au-Ag porous nanostructures with tailored structural features could be prepared by controlling the individual steps involved in this process,such as nanowire growth,surface modification,thermal diffusion,and dealloying.Structural characterizations reveal these Au-Ag porous nanotubes,non-porous nanotubes and porous nanowires possess novel nano-architectures with multimodal open porosity and excellent structural continuity and integrity,which make them particularly desirable as novel 1D nanocarriers for biomedical,drug delivery and sensing applications.
基金Supported by the National Key Research Program(No.2024-1129-954-112)National Natural Science Foundation of China(No.52372033)Guangxi Science and Technology Major Program(No.AA24263054)。
文摘Alkali-free SiO_(2)-Al_(2)O_(3)-CaO-MgO with different SiO_(2)/Al_(2)O_(3)mass ratios was prepared by conventional melt quenching method.The glass network structure,thermodynamic properties and elastic modulus changes with SiO_(2)and Al_(2)O_(3)ratios were investigated using various techniques.It is found that when SiO_(2)is replaced by Al_(2)O_(3),the Q^(4) to Q^(3) transition of silicon-oxygen network decreases while the aluminum-oxygen network increases,which result in the transformation of Si-O-Si bonds to Si-O-Al bonds and an increase in glass network connectivity even though the intermolecular bond strength decreases.The glass transition temperature(T_(g))increases continuously,while the thermal expansion coefficient increases and high-temperature viscosity first decreases and then increases.Meanwhile,the elastic modulus values increase from 93 to 102 GPa.This indicates that the elastic modulus is mainly affected by packing factor and dissociation energy,and elements with higher packing factors and dissociation energies supplant those with lower values,resulting in increased rigidity within the glass.
基金Funded by the National Natural Science Foundation of China(Nos.5226804252468035)。
文摘To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with graphene oxide(GO).The micro-pore structure of GOPM is characterized using LF-NMR and SEM.Fractal theory is applied to calculate the fractal dimension of pore volume,and the deterioration patterns are analyzed based on the evolution characteristics of capillary pores.The experimental results indicate that,after 25 salt-freeze-thaw cycles(SFTc),SO2-4 ions penetrate the matrix,generating corrosion products that fill existing pores and enhance the compactness of the specimen.As the number of cycles increases,the ongoing formation and expansion of corrosion products within the matrix,combined with persistent freezing forces,and result in the degradation of the pore structure.Therefore,the mass loss rate(MLR)of the specimens shows a trend of first decreasing and then increasing,while the relative dynamic elastic modulus(RDEM)initially increases and then decreases.Compared to the PC group specimens,the G3PM group specimens show a 28.71% reduction in MLR and a 31.42% increase in RDEM after 150 SFTc.The fractal dimensions of the transition pores,capillary pores,and macropores in the G3PM specimens first increase and then decrease as the number of SFTc increases.Among them,the capillary pores show the highest correlation with MLR and RDEM,with correlation coefficients of 0.97438 and 0.98555,respectively.
基金supported by National Natural Science Foundation of China(No.52025055 and 52275571)Basic Research Operation Fund of China(No.xzy012024024).
文摘Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality.
基金Supported by the Key Science&Technology Project of Guangzhou(No.202103000045)the National Natural Science Foundation of China(No.82070972,No.82271093).
文摘AIM:To investigate the effects of shortening the duration of silicone oil tamponade on retinal structure and function in patients undergoing silicone oil removal(SOR)after surgery for primary rhegmatogenous retinal detachment(RRD).METHODS:A total of 58 eligible patients were enrolled and randomly assigned to two groups based on tamponade duration:the short-term group(30-45d)and the conventional group(≥90d).Comprehensive evaluations were performed before and after SOR,including slitlamp examination,best-corrected visual acuity(BCVA)measurement,intraocular pressure(IOP)testing,optical coherence tomography(OCT),optical coherence tomography angiography(OCTA),microperimetry,electroretinography(ERG),and visual evoked potential(VEP)assessment.RESULTS:A total of 33 patients(23 males and 10 females;33 eyes)were enrolled in the short-term SO tamponade group with mean age of 52.45±9.35y,and 25 patients(15 males and 10 females;25 eyes)were enrolled in the conventional SO tamponade group with mean age of 50.80±12.06y.Compared with the conventional group,the short-term silicone oil tamponade group had a significantly lower incidence of silicone oil emulsification and cataract progression,with no significant difference in retinal reattachment success rate.Structurally,short-term tamponade was associated with increased thickness of the retinal ganglion cell layer(RGCL)in the nasal and superior macular regions and improved recovery of superficial retinal vascular density in these areas.Functionally,the shortterm group showed better BCVA and retinal sensitivity both before and 1mo after SOR;additionally,the P100 amplitude in VEP tests was significantly increased in this group.CONCLUSION:Shortening the duration of silicone oil tamponade effectively reduces damage to retinal structure and function without compromising the success rate of retinal reattachment in patients with primary RRD.
基金sponsored by the open fund of key laboratory of functional organometallic materials of ordinary university in Hunan province (No. 09K099, 10K010)science and technology projects in Hunan province (No. 2010JT4041)sponsored by key discipline of Hunan Province and scientific development plan of Hengyang city (No. 2009KG52)
文摘A one-dimensional chain chlorodibenzyltin 2-quininate has been synthesized and characterized by IR, NMR spectra and elemental analysis. The crystal structure has been determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group I4（—） with a = 19.1171（10）, b = 19.1171（10）, c = 12.5158（6） , Z = 8, V = 4574.1（4） 3, Dc = 1.477 g·cm-3, μ（MoKα） = 1.252 mm-1, F（000） = 2032, R = 0.0259 and wR = 0.0723. In the complex, the tin atom is six-coordinated to adopt a distorted octahedral configuration with bridging carboxyl of quinoline-2-carboxylic acid. The result of fluorescence spectrum analysis shows that the title complex at room temperature exhibits an intense photoluminescence with maximum emission at 364.2 nm （λex = 303.0 nm）.
基金The project was supported by the Education Office of Jilin Province (No. 0047)
文摘A new metal-organic coordination polymer [Zn（ipt）（im）2]2n·3nH2O 1 has been obtained by using hydrothermal synthesis and characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group P2（1/n） with a = 10.653（3）, b = 17.891（6）, c = 10.743（4）A^°,β= 117.093（5）°, V= 1822.9（10） A^°3, Mr= 413.65, Dc = 1.507 g/cm^3,/t（MoKa） = 1.390 mm^-1, F（000） = 840, Z = 4, the final R = 0.0444 and wR = 0.1066 for 2434 observed reflections （I〉 2σ（I））. Furthermore, compound 1 shows blue photoluminescent property at room temperature.
基金financial support Independent Innovation Foundation of Shandong University(IIFSDU-2009JQ011)
文摘One-dimensional Cd S@TiO_2 core-shell heterostructures were fabricated via the hydrolysis of tetrabutyl titanate(TBT) on preformed Cd S nanowires. The as-prepared products were characterized by X-ray diffraction, transmission electron microscopy, selected area electron diffraction and diffuse reflectance spectroscopy techniques. Results demonstrated that the hydrolysis of TBT had a great influence on the morphology of the coated TiO_2 shell, resulting in the formation of TiO_2 nanoparticles and nanolayer-modified Cd S@TiO_2 heterostructures. Degradation of methylene blue using Cd S@TiO_2 core-shell heterostructures as photocatalysts under visible light irradiation was investigated. Comparative photocatalytic tests showed that the TiO_2 nanoparticles-modified heterostructure exhibited a superior activity due to the passivity of photogenerated charge carriers.
基金supported by the Foundation of Education Committee of Hunan Province(06C195)the Research Award Fund for Outstanding Young Teachers of Hengyang Normal University(2006)Supported by the construct program of the key discipline in hunan province.
文摘A one-dimensional chain coordination polymer [Cu（phen）（2,4,6-TMBA）2（H2O）]n has been synthesized by reacting 2,4,6-trimethyl-benzoic acid, 1,10-phenanthroline and Cu（Ⅱ） perchlorate and its structure was characterized. Crystal data for this complex： tetragonal, space group I41, a = 2.0293（3）, b = 2.0293（3）, c = 1.3758（2） nm, α =β= γ = 90°, V= 5.6657（13） nm3, Dc= 1.379 g/cm3, Z = 8, μ（MoKa） = 0.815 mm-1, Mr = 588.14, F（000） = 2456, S = 1.047, R = 0.0459 and wR = 0.1053. The crystal structure shows that two neighboring Cu（Ⅱ） ions are linked together by one bridging-chelating 2,4,6-trimethyl-benzoic group, forming a one-dimensional chain structure. Each Cu（Ⅱ） ion is coordinated with two nitrogen atoms from one 1,10-phenanthroline molecule, three oxygen atoms from three 2,4,6-trimethyl-benzoic acid molecules and one oxygen atom from one water molecule, giving a six-coordinate distorted octahedral coordination geometry. The cyclic voltammetry behavior of the complex was also investigated.
基金supported by the National Natural Science Foundation of China (No. 21172105)the Foundation of the Education Department of Henan Province (No. 2011A150021)
文摘A new cadmium（Ⅱ） polymer [Cd（tdc）（Phen）]n 1 （H2tdc = thiophene-3,4-dicar-boxylic acid, Phen = 1,10-phenanthroline） was synthesized under hydrothermal conditions. The compound crystallizes in the triclinic system, space group P , with a = 7.3150（10）, b = 10.3598（14）, c = 10.8784（15） , α = 82.2740（10）, β = 72.9730（10）, γ = 80.236（2）°, V = 773.68（18） 3, Z = 2, Mr = 462.74, Dc = 1.986 Mg/m3, μ = 1.58 mm-1, F（000） = 456, the final R = 0.0218 and wR = 0.0465 for 3361 observed reflections with Ⅰ 〉 2σ（Ⅰ）. The compound presents a one-dimensional （1-D） double-stranded structure and exhibits fluorescent emission at room temperature. Furthermore, infrared spectroscopy, elemental analyses, thermogravimetric analysis and powder X-ray diffraction properties of the compound are also investigated.
基金World Premier International Research Center Initiative(WPI Initiative)on Materials Nanoarchitronics,MEXT,Japanthe Japan Society for the Promotion of Science (JSPS)for a support in the form of a fellowship tenable at the National Institute for Materials Science,Tsukuba,Japan.
文摘A focus of the current nanotechnology has shifted from routine fabrication of nanostructures to designing functional electronic devices and realizing their immense potentials for applications. Due to infusion of multi-functionality into a single system, the utilization of hetero-, core/shell and hierarchical nanostructures has become the key issue for building such devices. ZnS, due to its direct wide bandgap, high index of refraction, high transparency in the visible range and intrinsic polarity, is one of the most useful semiconductors for a wide range of electronics applications. This article provides a dense review of the state-of-the-art research activities in one-dimensional （1D） ZnS-based hetero-, core/shell and hierarchical nanostructures. The particular emphasis is put on their syntheses and applications.
基金The project was supported by the Education Office of Jilin Province (No. 0047)
文摘A metal-organic coordination polymer [Cd（bpy）（BDC）]n·nbpy （bpy = 2,2-bipyri-dine, H2BDC = terephthalic acid） has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group C2/c with a = 15.723（5）, b = 21.695（5）, c = 7.576（5） A, β = 116.171（7）°, V = 2319.3（18）A^3, C28H20CdN4O4, Mr = 588.88, Dc = 1.686 g/cm^3, μ（MoKα） = 0.987 mm^-1, F（000） = 1184, Z = 4, the final R = 0.0464 and wR = 0.0831 for 1882 observed reflections （Ⅰ〉 2σ（Ⅰ））. It exhibits a three-dimensional network with channels constructed from one-dimensional coordination chains via C–H…O hydrogen bonds and significant aromatic π-π stacking interactions.
基金the Education Office of Jilin Province (No. 0047)
文摘A new one-dimensional copper coordination polymer chain has been prepared and fully characterized by single-crystal X-ray diffraction, elemental analyses and IR spectroscopy. The compound { [Cu2（C2O4）2（inta）4]（inta）}n 1 crystallizes in the triclinic system, space group P1, with a = 8.4722（5）, b = 10.9825（6）, c = 11.6128（6）A, α= 104.8050（10）,β = 102.5740（10）, γ= 109.6890（10）°, V= 927.18（9） A3, Mr = 929.79, Z = 1, Dc = 1.665 g/cm^3, F（000） = 475, μ = 1.231 mm^-1, R = 0.0453 and wR = 0.1185 for 3290 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Of the compound, the Cu center is octahedrally coordinated with oxalate acting as a tetra-dentate ligand coordinated to the copper atom and each inta serving as a terminal ligand by employing only one N-donor to coordinate with the Cu center. An infinite {Cu2（C2O4）2}∞ chain is formed along the c axis. Furthermore, the 1D chains are held together via extensive hydrogen-bonding interactions to generate a three-dimensional network with 1D channels （ca. 5.491A×11.507A） where inta molecules are filled.
基金Project supported by the Natural Science Foundation of Hunan Province (No. 05JJ30016), Foundation of Education Committee of Hunan Province (05C001), Foundation of Hengyang Sci. & Tech. Bureau (2005Cg10-23) and Fund for Distinguished Young Cadreman of Hengyang Normal University(2006)
文摘A one-dimensional chain cobalt（Ⅱ） coordination polymer with 2,4,6-trimethyl- benzoic acid, 4,4′-bipyridine and cobalt perchlorate anhydrous has been synthesized and characterized in the mixture solvent of water and alcohol. Crystal data for this complex： monoclinic, space group C2/c, a = 2.3805（8）, b = 1.1464（4）, c = 1.5807（5） nm, y = 128.435（4）°, V= 3.3791（18） nm^3, Dc = 1.246 g/cm^3, Z = 4, F（000） = 1340, final GooF = 1.009, R = 0.0504 and wR = 0.1287. Structural analysis shows that the cobalt ion is coordinated with two nitrogen atoms of one 4,4′- bipyridine molecule and four oxygen atoms from two 2,4,6-trimethylbenzoic acid molecules and two alcohol molecules, giving a distorted octahedral coordination geometry. The result of TG analysis indicates that the title complex is stable till 200 ℃.
基金Supported by the Science and Technology Development Projects of Jilin Province(No.20150101007JC)
文摘A new one-dimensional Mg（Ⅱ） coordination polymer, [Mg（L）（phen）（H2O）]（1）, has been hydrothermally synthesized by using 3,5-dinitro-salicylic acid（H2L） and 1,10-phenanthroline（phen）. It crystallizes in monoclinic, space group C2/c with a = 33.038（7）, b = 6.6481（13）, c = 22.750（5） A, β = 126.99（3）°, V = 3991.1（14） A3, Z = 8, C19H12 MgN4O8, Mr = 448.64, Dc = 1.493 g/cm3, F（000） = 1840, μ（Mo Ka） = 0.146 mm-1, R = 0.0559 and w R = 0.0975. In 1, each L anion bridges two Mg（Ⅱ） atoms to give one-dimensional zigzag chains with the Mg…Mg separation of 5.34 ？, which are extended by π-π stacking interactions between 1,10-phenanthroline ligands into a two-dimensional supramolecular layer. Moreover, the O–H…O hydrogen-bonding interactions further stabilize the layer structure of 1. The luminescent property was also studied for 1 in solid state at room temperature. In addition, natural bond orbital（NBO） analysis was performed by the B3LYP/LANL2 DZ method in Gaussian 09 Program. The calculation results show obvious covalent interaction between the coordinated atoms and Mg（Ⅱ） ion.
