INDETERMINATE-DOMAIN proteins(IDDs)are a plant-specific transcription factor family characterized by a conserved ID domain with four zinc finger motifs.Previous studies have demonstrated that IDDs coordinate a diversi...INDETERMINATE-DOMAIN proteins(IDDs)are a plant-specific transcription factor family characterized by a conserved ID domain with four zinc finger motifs.Previous studies have demonstrated that IDDs coordinate a diversity of physiological processes and functions in plant growth and development,including floral transition,plant architecture,seed and root development,and hormone signaling.In this review,we especially summarized the latest knowledge on the functions and working models of IDD members in Arabidopsis,rice,and maize,particularly focusing on their role in the regulatory network of biotic and abiotic environmental responses,such as gravity,temperature,water,and pathogens.Understanding these mechanisms underlying the function of IDD proteins in these processes is important for improving crop yields by manipulating their activity.Overall,the review offers valuable insights into the functions and mechanisms of IDD proteins in plants,providing a foundation for further research and potential applications in agriculture.展开更多
A novel method for noise removal from the rotating accelerometer gravity gradiometer(MAGG)is presented.It introduces a head-to-tail data expansion technique based on the zero-phase filtering principle.A scheme for det...A novel method for noise removal from the rotating accelerometer gravity gradiometer(MAGG)is presented.It introduces a head-to-tail data expansion technique based on the zero-phase filtering principle.A scheme for determining band-pass filter parameters based on signal-to-noise ratio gain,smoothness index,and cross-correlation coefficient is designed using the Chebyshev optimal consistent approximation theory.Additionally,a wavelet denoising evaluation function is constructed,with the dmey wavelet basis function identified as most effective for processing gravity gradient data.The results of hard-in-the-loop simulation and prototype experiments show that the proposed processing method has shown a 14%improvement in the measurement variance of gravity gradient signals,and the measurement accuracy has reached within 4E,compared to other commonly used methods,which verifies that the proposed method effectively removes noise from the gradient signals,improved gravity gradiometry accuracy,and has certain technical insights for high-precision airborne gravity gradiometry.展开更多
Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typ...Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typical and well-preserved Heiyu section(HY),where,to determine the paleoclimatic changes during Marine Isotope Stage 3a.Optically stimulated luminescence dates of the HY formation range from 0.26±0.02 ka to 39.00±2.00 ka.In addition,the ages of G1 and G2 were estimated using the Bayesian model to be 39.60-40.50 and 29.00-29.50 ka.G1 and G2 are mainly composed of fine and medium gravel,both of which were subangular to subrounded limestone,with gravel directions to NE and E.The average flow velocity,average depth,and flood peak flow of G1 are 1.10 m/s,0.49 m,and 37.04 m^(3)/s,respectively,calculated using the flow energy method,whereas those of G2 are 0.98 m/s,0.38 m,and 18.38 m^(3)/s,respectively.Analysis of climate proxy indices show that the sedimentary environment of the gravel and loess in HY might be a regional response to global change.展开更多
Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky Way.Photometric surveys,especially those with near-ultraviolet filters,can offer...Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky Way.Photometric surveys,especially those with near-ultraviolet filters,can offer accurate measurements of stellar parameters,with the precision comparable to that from low/medium resolution spectroscopy.In this study,we explore the capability of measuring stellar atmospheric parameters from Chinese Space Station Telescope(CSST)broad-band photometry(particularly in the near-ultraviolet bands),based on synthetic colors derived from model spectra.We find that colors from the optical and near-ultraviolet filter systems adopted by CSST show significant sensitivities to the stellar atmospheric parameters,especially the metallicity.According to our mock data tests,the precision of the photometric metallicity is quite high,with typical values of0.17 and 0.20 dex for dwarf and giant stars,respectively.The precision of the effective temperature estimated from broad-band colors are within 50 K.展开更多
This study conducted a 16-week comparative experiment with 160 students from Jinan No.5 Middle School in Shandong Province as the experimental subjects.During the implementation of the experiment,the subjects were div...This study conducted a 16-week comparative experiment with 160 students from Jinan No.5 Middle School in Shandong Province as the experimental subjects.During the implementation of the experiment,the subjects were divided into two groups:an experimental group and a control group.The experimental group was subjected to physical exercise interventions using sports game teaching methods during physical education class,while the control group followed traditional physical education teaching methods.The results showed that the psychological health status of the students in the experimental group was significantly better than that of the control group after the experiment.The application of sports games helps to improve the psychological health of middle school students in the course of physical education,promoting a positive and forward direction in student psychology and is an effective means to enhance the psychological health level of middle school students.展开更多
We used the Five-hundred-meter Aperture Spherical radio Telescope(FAST)to search for the molecular emissions in the L-band between 1.0 and 1.5 GHz toward four comets,C/2020 F3(NEOWISE),C/2020 R4(ATLAS),C/2021 A1(Leona...We used the Five-hundred-meter Aperture Spherical radio Telescope(FAST)to search for the molecular emissions in the L-band between 1.0 and 1.5 GHz toward four comets,C/2020 F3(NEOWISE),C/2020 R4(ATLAS),C/2021 A1(Leonard),and 67P/Churyumov-Gerasimenko during or after their perihelion passages.Thousands of molecular transition lines fall in this low-frequency range,many attributed to complex organic or prebiotic molecules.We conducted a blind search for the possible molecular lines in this frequency range in those comets and could not identify clear signals of molecular emissions in the data.Although several molecules have been detected at high frequencies of greater than100 GHz in comets,our results confirm that it is challenging to detect molecular transitions in the L-band frequency ranges.The non-detection of L-band molecular lines in the cometary environment could rule out the possibility of unusually strong lines,which could be caused by the masers or non-LTE effects.Although the line strengths are predicted to be weak,for FAST,using the ultra-wide bandwidth receiver and improving the radio frequency interference environments would enhance the detectability of those molecular transitions at low frequencies in the future.展开更多
LLE data of cyclooctane/3-methylpentane + benzene/toluene + N-methylpyrrolidone (NMP) at 298.15 Kand 313.15 K under a pressure of 101.3 kPa were measured in this work. The Othmer-Tobias and Handequations were adopted ...LLE data of cyclooctane/3-methylpentane + benzene/toluene + N-methylpyrrolidone (NMP) at 298.15 Kand 313.15 K under a pressure of 101.3 kPa were measured in this work. The Othmer-Tobias and Handequations were adopted to validate the reliability of LLE data, where the correlation coefficients (R2) wereclose to unity, indicating the high reliability of the experimental data. The experimental data were analyzed using the distribution coefficient (D) and separation factor (S), and the effect of NMP extracting benzene and toluene from aromatics was explored. Meanwhile, the reason for the different extractionefficiencies of benzene and toluene using NMP was analyzed by quantum chemical calculations. TheNRTL and UNIQUAC thermodynamic models were used to correlate the liquid–liquid equilibrium data,and the relevant binary interaction parameters were obtained. The calculated root mean square deviation(RMSD) were all less than 0.0063, indicating that the obtained binary interaction parameters can be usedto simulate and calculate the extraction of aromatics using NMP.展开更多
A novel alpha function for Peng-Robinson equation of state was proposed and generalized with acentric factor and dipole moment for predicting thermodynamic properties of non-polar,weakly polar,and polar compounds.The ...A novel alpha function for Peng-Robinson equation of state was proposed and generalized with acentric factor and dipole moment for predicting thermodynamic properties of non-polar,weakly polar,and polar compounds.The parameters of new alpha function were fitted with vapor pressures of 70 compounds.Six different methods were investigated for the correlation of parameters of new alpha function and Heyen alpha function.The generalized new alpha function passed the consistency test.The results indicated that the predictive accuracy of generalized new alpha function and generalized Heyen alpha function was improved for the estimation of vapor pressure of 11 kinds of compounds,with the average relative deviations(ARDs)being 2.60%and 2.76%.The ARDs of the two generalized alpha functions were 2.04%and 2.09%for the enthalpy of vaporization.However,the generalized new alpha function and the other alpha functions had great deviations for the prediction of liquid volumes and isobaric heat capacities.The alpha function that was generalized with acentric factor and reduced dipole moment was more accurate than that was generalized with acentric factor,especially for the prediction of vapor pressure and enthalpy of vaporization of polar compounds.展开更多
In maize,prolificacy,the number of ears per plant,is a trait of interest to maize breeders for breeding high grain-yielding cultivars or specialty corn,as well as being a model trait for decoding the molecular mechani...In maize,prolificacy,the number of ears per plant,is a trait of interest to maize breeders for breeding high grain-yielding cultivars or specialty corn,as well as being a model trait for decoding the molecular mechanism of maize evolution.Its genetic basis remains largely unknown.We identified a stable quantitative trait locus,qEN7,for ear number on chromosome 7 in both F2 and F2:3 populations derived from a single cross between the nonprolific inbred line Mo17 and the prolific inbred line LAN404 derived from the landrace PI217404.qEN7 explained 10.7%-11.9%of phenotypic variation,and the LAN404 allele at this locus was associated with an increase of around one ear per plant.qEN7 was confined by fine-mapping to a 0.56-Mb region containing eight annotated genes.Analysis of selection,gene expression patterns in various maize tissues,and sequence polymorphisms between the two parental lines suggested that Zm00001d020683,which encodes a putative INDETERMINATE DOMAIN(IDD)transcription factor,is the most likely candidate gene underlying qEN7.Zm00001d020683 is expressed mainly in the vegetative meristem,immature ears,and internodes and has undergone selection during maize improvement.The identification of qEN7 and the prediction of its candidate gene sheds some light on the evolution of maize ear number and provides a novel resource for breeding of multi-ear maize cultivars.展开更多
Dust extinction law is crucial to recover the intrinsic energy distribution of celestial objects and infer the characteristics of interstellar dust.Based on the traditional pair method,an improved pair method is propo...Dust extinction law is crucial to recover the intrinsic energy distribution of celestial objects and infer the characteristics of interstellar dust.Based on the traditional pair method,an improved pair method is proposed to model the dust extinguished spectral energy distribution(SED)of an individual star.Instead of the mathematically parameterizing extinction curves,the extinction curves in this work are directly from the silicate-graphite dust model,so that the dust extinction law can be obtained and the dust properties can be analyzed simultaneously.The ATLAS9 stellar model atmosphere is adopted for the intrinsic SEDs in this work,while the silicate-graphite dust model with a dust size distribution of dn da~a^(-a)exp(-a a_(c)),0.005<a<5μmfor each component is adopted for the model extinction curves.One typical extinction tracer in the dense region(V410 Anon9)and one in the diffuse region(Cyg OB2#12)of the Milky Way are chosen to test the reliability and the practicability of the improved pair method in different stellar environments.The results are consistent with their interstellar environments and are in agreement with the previous observations and studies,which prove that the improved pair method is effective and applicable in different stellar environments.In addition to the reliable extinction results,the derived parameters in the dust model can be used to analyze the dust properties,which cannot be achieved by other methods with the mathematical extinction models.With the improved pair method,the stellar parameters can also be inferred and the extinction law beyond the wavelengths of observed data can be predicted based on the dust model as well.展开更多
We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a disper...We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm^(-3).The averaged pulse profile shows two distinct components.We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23.We used a threshold of 5σ_(ep) to measure the nulling fraction(NF)as 63%±1.5%.The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods.We examined the reliability of the periodicity by comparing it to random noise injection.The NF,E,and modulation periodicity P_(M) of PSR J1909+0122 were compared with other periodic nulling pulsars,showing that the source of J1909+0122 has the second largest NF in the population.Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar.The measured P and P values disfavor dipolar geometry for polar gap models,and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line.In this work,PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties,which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations.展开更多
The potential application of gold nanoparticles(GNPs)in biomedicine has been extensively reported.However,there is still too much puzzle about their real face and potential health risks in comparison with the commerci...The potential application of gold nanoparticles(GNPs)in biomedicine has been extensively reported.However,there is still too much puzzle about their real face and potential health risks in comparison with the commercial drug molecules.The emergence of atomically precise gold nanoclusters(APGNCs)provides the opportunity to address the puzzle due to their ultrasmall size,defined molecular formula,editable surface engineering,available structures and unique physicochemical properties including excellent biocompatibility,strong luminescence,enzyme-like activity and efficient renal clearance,et al.Recently,these advantages of APGNCs also endow them promising performances in healthcare such as bioimaging,drug delivery,antibacterial and cancer therapy.Especially,their clear composition and structures like the commercial drug molecules facilitate the study of their functions and the structure-activity relationship in healthcare,which is essential for the guided design of APGNC nanomedicine.Therefore,this review will focus the advantages and recent progress of APGNCs in health care and envision their prospects for the future.展开更多
The amount of low-temperature heat generated in industrial processes is high,but recycling is limited due to low grade and low recycling efficiency,which is one of the reasons for low energy efficiency.It implies that...The amount of low-temperature heat generated in industrial processes is high,but recycling is limited due to low grade and low recycling efficiency,which is one of the reasons for low energy efficiency.It implies that there is a great potential for low-temperature heat recovery and utilization.This article provided a detailed review of recent advances in the development of low-temperature thermal upgrades,power generation,refrigeration,and thermal energy storage.The detailed description will be given from the aspects of system structure improvement,work medium improvement,and thermodynamic and economic performance evaluation.It also pointed out the development bottlenecks and future development trends of various technologies.The low-temperature heat combined utilization technology can recover waste heat in an all-round and effective manner,and has great development prospects.展开更多
Solvothermal reactions of 3,5-dimethyl-2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl) pyridine (L), 1,4-benzendicarboxylic acid (H2bdc), and transitional metal cations of M11 (M = Mn, Co, Cd) in the presence of oxa...Solvothermal reactions of 3,5-dimethyl-2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl) pyridine (L), 1,4-benzendicarboxylic acid (H2bdc), and transitional metal cations of M11 (M = Mn, Co, Cd) in the presence of oxalic acid (H2ox) afford three novel supramolecular polymers (CPs), namely, {[M2(ox)(L)2][bdc][M2(Hox)2(OH)(H2O)4]·3H2O}n (M = Mn for 1, Co for 2, Cd for 3). Single-crystal X-ray diffraction analysis reveals that complexes 1-3 are isostructural and the 3D supramolecular structure was connected through non-covalent interactions. With the help of H2ox, the L ligands cheated with center atoms forming a butterfly [M2(ox)(L)2]2+ building block. The bdc2- ligand linked with the unprecedented [M2(Hox)2(OH)2(H2O)4] units through strong O-H...O hydrogen bonds forming a zigzag chain, which are further connected through π-π interactions between L and bdc2- ligands to form a 3D supramolecular structure. Moreover, elemental analyses, IR, thermogravimetric, PXRD and luminescence have been investigated.展开更多
One novel copper(II)-organic compound,namely Cu[Cu2(PP)2](CBPC)2]·2(H2O)(1,H2CBPC = 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-(2-pyridyl)pyrazole),was designed...One novel copper(II)-organic compound,namely Cu[Cu2(PP)2](CBPC)2]·2(H2O)(1,H2CBPC = 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-(2-pyridyl)pyrazole),was designed and synthesized under hydrothermal conditions.X-ray diffraction analysis reveals that two Cu(II)ions in the quasi-planar dimmer of [Cu2(PP)2] are linked by the carboxylate oxygen atoms on the phenyl ring and the imidazole ring,respectively,yielding one snake-shaped structure.Magnetic measurements reveal that compound 1 shows the strongly antiferromagnetic property.Crystal data of 1:C58H52Cu3N10O10,Mr = 1239.72,monoclinic,P21/c,a = 14.900(7),b = 15.029(7),c = 12.308(6),β = 102.519(9)o,V = 2691(2)3,Z = 2,Dc = 1.530 g/cm3,F(000)= 1274,μ = 1.246 mm-1,R = 0.0416,wR = 0.0780(I 2σ(I))and S = 0.999.展开更多
Two new coordination polymers,[Zn(bdc)(1,3-bimb)]n(1) and {[Mn2(ox)2(1,3,5tib)4/3]·4H2O}n(2)(H2ox = oxalic acid,H2bdc = terephthalic acid,1,3-bimb = 1,3-bis(imidazol-1ylmethyl)benzene,1,3,5-tib = 1...Two new coordination polymers,[Zn(bdc)(1,3-bimb)]n(1) and {[Mn2(ox)2(1,3,5tib)4/3]·4H2O}n(2)(H2ox = oxalic acid,H2bdc = terephthalic acid,1,3-bimb = 1,3-bis(imidazol-1ylmethyl)benzene,1,3,5-tib = 1,3,5-tri(imidazol-1-yl)benzene),were synthesized and characterized by elemental analysis,IR,powder X-ray diffraction(PXRD),and thermogravimetric(TG) analyses.X-ray diffracation analysis reveals that two kinds of zigzag chains [Zn(bdc)]n and [Zn(1,3-bimb)]n in compound 1 are interweaved to form a 3D 4-fold interpenetrated 66-dia framework.In compound 2,Mn(1) and Mn(2) are linked via 1,3,5-tib ligands to form two different nets of [Mn6(1,3,5-tib)6 ]n along the ab plane with inner-or outer-shape N–Mn–N angles,which are connected by 1D infinite [Mn2(ox)2 ]n chains via Mn–O bonds to result in a(3,3,3,4,4)-connected(4·8·10)3(4·82)3(4·83·102)6(82·104·3)3(83)4 topology.Moreover,the photoluminescence of 1 has been investigated.The crystal of 1 crystallizes in orthorhombic,space group Pna2 with a = 13.2267(6),b = 9.1717(4),c = 17.4492(8),V = 2116.79(16)3,Z = 4,C22 H18N4O4 Zn,Mr = 467.77,Dc = 1.468 g/cm3,F(000) = 960 and μ(MoKα) = 1.197 mm-1.The final R = 0.0280 and wR = 0.0618 for 3695 observed reflections with I 2(I) and R = 0.0389 and wR = 0.0653 for all data.The crystal of 2 crystallizes in rhombohedral,space group R-3 with a = 22.080(8),c = 31.19(2),V = 13167(11) 3,Z = 18,C24 H25 Mn2 N8 O13,Mr = 743.40,Dc = 1.688 g/cm3,F(000) = 6822 and μ(MoKα) = 0.945 mm-1.The final R = 0.0429 and wR = 0.1035 for 5160 observed reflections with I 2(I) and R = 0.0824 and wR = 0.1244 for all data.展开更多
One novel cobalt coordination polymer, {[Co(HTCB)(4,4'btb)]'HzO}n (1, H3TCB = 1,3,5-tris(4-carboxyphenyl)benzene, 4,4'-btb = 4,4'-bis(1,2,4-triazol-3-yl)biphenyl), has been synthesized and characterized ...One novel cobalt coordination polymer, {[Co(HTCB)(4,4'btb)]'HzO}n (1, H3TCB = 1,3,5-tris(4-carboxyphenyl)benzene, 4,4'-btb = 4,4'-bis(1,2,4-triazol-3-yl)biphenyl), has been synthesized and characterized by elemental analysis, IR, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. X-ray diffraction analysis reveals that complex 1 is a 2D 2-fold interpenetrated {44,62}-sql [Co(HTCB)(4,4'-btb)] sheet based on the 1D [Co(HTCB)]n chains and 1D [Co(4,4'-btb)]n chains. The crystal of 1 crystallizes in triclinic, space group P1 with a = 9.529(12), b = 13.914(16), c = 14.906(17) A, V= 1903(4) A3, Z = 2, C45H34N6CoO71 Mr= 829.71, Dc = 1.448 g/cm3, F(000) = 858 andμ(MoKa) = 0.514 mm-1. The final R = 0.0655 and wR = 0.1136 for 6603 observed reflections with 1 〉 2a(/) and R = 0.1136 and wR = 0.1747 for all data.展开更多
Titanium dioxide(TiO_2) has been investigated broadly as a stable,safe,and cheap anode material for sodium-ion batteries in recent years.However,the poor electronic conductivity and inherent sluggish sodium ion diffus...Titanium dioxide(TiO_2) has been investigated broadly as a stable,safe,and cheap anode material for sodium-ion batteries in recent years.However,the poor electronic conductivity and inherent sluggish sodium ion diffusion hinder its practical applications.Herein,a self-template and in situ vulcanization strategy is developed to synthesize self-supported hybrid nanotube arrays composed of nitrogen/sulfur-codoped carbon coated sulfur-doped TiO_2 nanotubes(S-TiO_2@NS-C) starting from H_2 Ti_2 O_5-H_2 O nanoarrays.The S-TiO_2@NS-C composite with one-dimensional nano-sized subunits integrates several merits.Specifically,sulfur doping strongly improves the Na~+ storage ability of TiO_2@C-N nanotubes by narrowing the bandgap of original TiO_2.Originating from the nanoarrays structures built from hollow nanotubes,carbon layer and sulfur doping,the sluggish Na~+ insertion/extraction kinetics is effectively improved and the volume variation of the electrode material is significantly alleviated.As a result,the S-TiO_2@NS-C nanoarrays present efficient sodium storage properties.The greatly improved sodium storage performances of S-TiO_2@NS-C nanoarrays confirm the importance of rational engineering and synthesis of hollow array architectures with higher complexity.展开更多
One novel entangled cobalt compound, {[Co3(nbta)2(4,4'-bpy)2(H2O)2](H2O)2}n (1, H3nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, 4,4'-bpy = 4,4'-bipyridyl), was prepared and characterized by X-my diffrac...One novel entangled cobalt compound, {[Co3(nbta)2(4,4'-bpy)2(H2O)2](H2O)2}n (1, H3nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, 4,4'-bpy = 4,4'-bipyridyl), was prepared and characterized by X-my diffraction, magnetism, elemental analysis, XPS, TGA and IR spectroscopy. The crystal of 1 crystallizes in monoclinic, space group Pc with a = 13.0717(16), b = 11.4167(14), c = 15.9342(19) A, β = 90.5190(10)°, V= 2377.9(5) A3, Z= 2, C48H36Co3N8O20, Mr = 1221.64, Dc = 1.706 g/cm3, F(000) = 1242 and μ(MoKa) = 1.128 mm^-1. The final R = 0.0497 and wR = 0.1461 for 4185 observed reflections with I 〉 20(0 and R = 0.0721 and wR = 0.1619 for all data. X-ray diffraction analyses revealed that Co(l) is linked by the nbta3- ligands to form the ladder shape along the c axis, which is further extended into two-dimensional networks via the joint of Co(2) along the a axis. Moreover, these two dimensional motifs are interconnected by the 4,4'-bpy bridges to form a complicated 3-D polymeric framework. Magnetic measurements revealed that compound 1 shows strong antiferromagnetic property.展开更多
Hydrothermal reactions of two imidazole derivatives (1,3,5-tib = 1,3,5-tris(1H- imidazol- 1 -yl)benzene, 1,4-bimb = 1,4-bis(1 H-imidazol- 1 -ylmethyl)benzene) and the ZnⅡ cations in the presence of oxalic acid ...Hydrothermal reactions of two imidazole derivatives (1,3,5-tib = 1,3,5-tris(1H- imidazol- 1 -yl)benzene, 1,4-bimb = 1,4-bis(1 H-imidazol- 1 -ylmethyl)benzene) and the ZnⅡ cations in the presence of oxalic acid (H2ox) afford two coordination polymers, namely, {[Zn(ox)(1,3,5- tib)]·2(H20)}n (1) and [Znl.5(OX)1.5(1,4-bimb)l.5]n (2). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction (PXRD) analyses. Both complexes 1 and 2 are based on the 1D zigzag [Zn(ox)]n chains, and their final structures are controlled by the two different imidazole linkers, which expanded the structure along different directions, finally giving a 3D dia net for 1 and a 2D sql layer for 2. Moreover, the luminescent properties of 1 and 2 have been investigated.展开更多
基金the National Natural Science Foundation of China(31800225 and 32370363)the Natural Science Foundation of Shandong Province(ZR2020MC027 and ZR2021QC213).
文摘INDETERMINATE-DOMAIN proteins(IDDs)are a plant-specific transcription factor family characterized by a conserved ID domain with four zinc finger motifs.Previous studies have demonstrated that IDDs coordinate a diversity of physiological processes and functions in plant growth and development,including floral transition,plant architecture,seed and root development,and hormone signaling.In this review,we especially summarized the latest knowledge on the functions and working models of IDD members in Arabidopsis,rice,and maize,particularly focusing on their role in the regulatory network of biotic and abiotic environmental responses,such as gravity,temperature,water,and pathogens.Understanding these mechanisms underlying the function of IDD proteins in these processes is important for improving crop yields by manipulating their activity.Overall,the review offers valuable insights into the functions and mechanisms of IDD proteins in plants,providing a foundation for further research and potential applications in agriculture.
文摘A novel method for noise removal from the rotating accelerometer gravity gradiometer(MAGG)is presented.It introduces a head-to-tail data expansion technique based on the zero-phase filtering principle.A scheme for determining band-pass filter parameters based on signal-to-noise ratio gain,smoothness index,and cross-correlation coefficient is designed using the Chebyshev optimal consistent approximation theory.Additionally,a wavelet denoising evaluation function is constructed,with the dmey wavelet basis function identified as most effective for processing gravity gradient data.The results of hard-in-the-loop simulation and prototype experiments show that the proposed processing method has shown a 14%improvement in the measurement variance of gravity gradient signals,and the measurement accuracy has reached within 4E,compared to other commonly used methods,which verifies that the proposed method effectively removes noise from the gradient signals,improved gravity gradiometry accuracy,and has certain technical insights for high-precision airborne gravity gradiometry.
基金the National Natural Science Foundation of China(Grant Nos.41472159,41172160,41371537).
文摘Investigation of rarely studied gravel layers found in the loess in Shandong Province,eastern China,reveals the fabric characteristics of two gravel layers(G1,G2)and the sedimentary characteristics of loess at the typical and well-preserved Heiyu section(HY),where,to determine the paleoclimatic changes during Marine Isotope Stage 3a.Optically stimulated luminescence dates of the HY formation range from 0.26±0.02 ka to 39.00±2.00 ka.In addition,the ages of G1 and G2 were estimated using the Bayesian model to be 39.60-40.50 and 29.00-29.50 ka.G1 and G2 are mainly composed of fine and medium gravel,both of which were subangular to subrounded limestone,with gravel directions to NE and E.The average flow velocity,average depth,and flood peak flow of G1 are 1.10 m/s,0.49 m,and 37.04 m^(3)/s,respectively,calculated using the flow energy method,whereas those of G2 are 0.98 m/s,0.38 m,and 18.38 m^(3)/s,respectively.Analysis of climate proxy indices show that the sedimentary environment of the gravel and loess in HY might be a regional response to global change.
基金the science research grants from the China Manned Space Project with No.CMS-CSST-2021-A08.Y.Hthe science research grants from the China Manned Space Project with No.CMS-CSST-2021-B05+3 种基金the NSFC for grant Nos.11903027 and11833006the NSFC for grant Nos.11973001,12090040,and 12090044the National Key R&D Program of China for grant No.2019YFA0405503.H.W.Zthe National Key R&D Program of China for grant No.2019YFA0405504。
文摘Deriving atmospheric parameters of a large sample of stars is of vital importance to understand the formation and evolution of the Milky Way.Photometric surveys,especially those with near-ultraviolet filters,can offer accurate measurements of stellar parameters,with the precision comparable to that from low/medium resolution spectroscopy.In this study,we explore the capability of measuring stellar atmospheric parameters from Chinese Space Station Telescope(CSST)broad-band photometry(particularly in the near-ultraviolet bands),based on synthetic colors derived from model spectra.We find that colors from the optical and near-ultraviolet filter systems adopted by CSST show significant sensitivities to the stellar atmospheric parameters,especially the metallicity.According to our mock data tests,the precision of the photometric metallicity is quite high,with typical values of0.17 and 0.20 dex for dwarf and giant stars,respectively.The precision of the effective temperature estimated from broad-band colors are within 50 K.
文摘This study conducted a 16-week comparative experiment with 160 students from Jinan No.5 Middle School in Shandong Province as the experimental subjects.During the implementation of the experiment,the subjects were divided into two groups:an experimental group and a control group.The experimental group was subjected to physical exercise interventions using sports game teaching methods during physical education class,while the control group followed traditional physical education teaching methods.The results showed that the psychological health status of the students in the experimental group was significantly better than that of the control group after the experiment.The application of sports games helps to improve the psychological health of middle school students in the course of physical education,promoting a positive and forward direction in student psychology and is an effective means to enhance the psychological health level of middle school students.
基金supported by a grant from the National Natural Science Foundation of China(NSFC)No.11988101by the NSFC grant Nos.11703047,11773041,U2031119,12173052,12173053,12373032,and 11963002+6 种基金support from the China Postdoctoral Science Foundation grant No.2023M733271the Foundation of Education Bureau of Guizhou Province,China(grant No.KY(2020)003)supported by the International Partnership Program of the Chinese Academy of Sciences,program No.114A11KYSB20210010the Youth Innovation Promotion Association of the Chinese Academy of Sciences(ID Nos.2023064,2018075,and Y2022027)the support from the National Key R&D Program of China grant Nos.2022YFC2205202 and 2020SKA0120100supported by the CAS“Light of West China”Programthe support by the NSFC grant No.12373026。
文摘We used the Five-hundred-meter Aperture Spherical radio Telescope(FAST)to search for the molecular emissions in the L-band between 1.0 and 1.5 GHz toward four comets,C/2020 F3(NEOWISE),C/2020 R4(ATLAS),C/2021 A1(Leonard),and 67P/Churyumov-Gerasimenko during or after their perihelion passages.Thousands of molecular transition lines fall in this low-frequency range,many attributed to complex organic or prebiotic molecules.We conducted a blind search for the possible molecular lines in this frequency range in those comets and could not identify clear signals of molecular emissions in the data.Although several molecules have been detected at high frequencies of greater than100 GHz in comets,our results confirm that it is challenging to detect molecular transitions in the L-band frequency ranges.The non-detection of L-band molecular lines in the cometary environment could rule out the possibility of unusually strong lines,which could be caused by the masers or non-LTE effects.Although the line strengths are predicted to be weak,for FAST,using the ultra-wide bandwidth receiver and improving the radio frequency interference environments would enhance the detectability of those molecular transitions at low frequencies in the future.
基金the National Natural Science Foundation of China(22178190)the National Youth Natural Science Foundation of China(CN)(22008129).
文摘LLE data of cyclooctane/3-methylpentane + benzene/toluene + N-methylpyrrolidone (NMP) at 298.15 Kand 313.15 K under a pressure of 101.3 kPa were measured in this work. The Othmer-Tobias and Handequations were adopted to validate the reliability of LLE data, where the correlation coefficients (R2) wereclose to unity, indicating the high reliability of the experimental data. The experimental data were analyzed using the distribution coefficient (D) and separation factor (S), and the effect of NMP extracting benzene and toluene from aromatics was explored. Meanwhile, the reason for the different extractionefficiencies of benzene and toluene using NMP was analyzed by quantum chemical calculations. TheNRTL and UNIQUAC thermodynamic models were used to correlate the liquid–liquid equilibrium data,and the relevant binary interaction parameters were obtained. The calculated root mean square deviation(RMSD) were all less than 0.0063, indicating that the obtained binary interaction parameters can be usedto simulate and calculate the extraction of aromatics using NMP.
基金supported by National Natural Science Foundation of China(22008129,22108138)。
文摘A novel alpha function for Peng-Robinson equation of state was proposed and generalized with acentric factor and dipole moment for predicting thermodynamic properties of non-polar,weakly polar,and polar compounds.The parameters of new alpha function were fitted with vapor pressures of 70 compounds.Six different methods were investigated for the correlation of parameters of new alpha function and Heyen alpha function.The generalized new alpha function passed the consistency test.The results indicated that the predictive accuracy of generalized new alpha function and generalized Heyen alpha function was improved for the estimation of vapor pressure of 11 kinds of compounds,with the average relative deviations(ARDs)being 2.60%and 2.76%.The ARDs of the two generalized alpha functions were 2.04%and 2.09%for the enthalpy of vaporization.However,the generalized new alpha function and the other alpha functions had great deviations for the prediction of liquid volumes and isobaric heat capacities.The alpha function that was generalized with acentric factor and reduced dipole moment was more accurate than that was generalized with acentric factor,especially for the prediction of vapor pressure and enthalpy of vaporization of polar compounds.
基金supported by the National Natural Science Foundation of China(91935302)the Beijing Outstanding Young Scientist Program(BJJWZYJH01201910019026)the Chinese Universities Scientific Fund(2022TC035).
文摘In maize,prolificacy,the number of ears per plant,is a trait of interest to maize breeders for breeding high grain-yielding cultivars or specialty corn,as well as being a model trait for decoding the molecular mechanism of maize evolution.Its genetic basis remains largely unknown.We identified a stable quantitative trait locus,qEN7,for ear number on chromosome 7 in both F2 and F2:3 populations derived from a single cross between the nonprolific inbred line Mo17 and the prolific inbred line LAN404 derived from the landrace PI217404.qEN7 explained 10.7%-11.9%of phenotypic variation,and the LAN404 allele at this locus was associated with an increase of around one ear per plant.qEN7 was confined by fine-mapping to a 0.56-Mb region containing eight annotated genes.Analysis of selection,gene expression patterns in various maize tissues,and sequence polymorphisms between the two parental lines suggested that Zm00001d020683,which encodes a putative INDETERMINATE DOMAIN(IDD)transcription factor,is the most likely candidate gene underlying qEN7.Zm00001d020683 is expressed mainly in the vegetative meristem,immature ears,and internodes and has undergone selection during maize improvement.The identification of qEN7 and the prediction of its candidate gene sheds some light on the evolution of maize ear number and provides a novel resource for breeding of multi-ear maize cultivars.
基金supported by the National Natural Science Foundation of China(NSFC)through grant Nos.12133002,U2031209 and 12203025Shandong Provincial Natural Science Foundation through project ZR2022QA064the CSST Milky Way and Nearby Galaxies Survey on Dust and Extinction Project CMS-CSST2021-A09。
文摘Dust extinction law is crucial to recover the intrinsic energy distribution of celestial objects and infer the characteristics of interstellar dust.Based on the traditional pair method,an improved pair method is proposed to model the dust extinguished spectral energy distribution(SED)of an individual star.Instead of the mathematically parameterizing extinction curves,the extinction curves in this work are directly from the silicate-graphite dust model,so that the dust extinction law can be obtained and the dust properties can be analyzed simultaneously.The ATLAS9 stellar model atmosphere is adopted for the intrinsic SEDs in this work,while the silicate-graphite dust model with a dust size distribution of dn da~a^(-a)exp(-a a_(c)),0.005<a<5μmfor each component is adopted for the model extinction curves.One typical extinction tracer in the dense region(V410 Anon9)and one in the diffuse region(Cyg OB2#12)of the Milky Way are chosen to test the reliability and the practicability of the improved pair method in different stellar environments.The results are consistent with their interstellar environments and are in agreement with the previous observations and studies,which prove that the improved pair method is effective and applicable in different stellar environments.In addition to the reliable extinction results,the derived parameters in the dust model can be used to analyze the dust properties,which cannot be achieved by other methods with the mathematical extinction models.With the improved pair method,the stellar parameters can also be inferred and the extinction law beyond the wavelengths of observed data can be predicted based on the dust model as well.
基金supported by the National Natural Science Foundation of China(NSFC)Grant Nos.11988101,1172531312041303,12041304,12203045,12203070,12103013,T2241020the National SKA Program of China(Nos.2020SKA0120200,2022SKA0130100,2022SKA0130104)+5 种基金the Foundation of Science and Technology of Guizhou Province(No.(2021)023)the Foundation of Guizhou Provincial Education Department(Nos.KY(2021)303,KY(2020)003)support from the National Natural Science Foundation of China under grant U2031117the Youth Innovation Promotion Association CAS(id.2021055)CAS Project for Young Scientists in Basic Research(grant YSBR006)the Cultivation Project for FAST Scientific Payoff and Research Achievement of CAMS-CAS。
文摘We report the discovery of PSR J1909+0122 by the Five-hundred-meter Aperture Spherical Radio Telescope(FAST)as part of the Commensal Radio Astronomy FAST Survey.PSR J1909+0122 has a spin period of 1.257 s and a dispersion measure of 186.2 pc cm^(-3).The averaged pulse profile shows two distinct components.We performed a single-pulse study based on a one-hour observation at 1.25 GHz on 2021 August 23.We used a threshold of 5σ_(ep) to measure the nulling fraction(NF)as 63%±1.5%.The longitude-resolved fluctuation spectra and fast Fourier transform spectra of the binary sequences revealed the quasi-periodicity of nulling with a period of 30 rotation periods.We examined the reliability of the periodicity by comparing it to random noise injection.The NF,E,and modulation periodicity P_(M) of PSR J1909+0122 were compared with other periodic nulling pulsars,showing that the source of J1909+0122 has the second largest NF in the population.Long-term timing observations over six months were used to derive the phase-connected ephemeris of this pulsar.The measured P and P values disfavor dipolar geometry for polar gap models,and the prediction for a space-charge-limited flow model in the case of inverse Compton scattering is only just above the death line.In this work,PSR J1909+0122 has revealed possible correlations between nulling behavior and pulsar properties,which will help to shed light on the pulsar emission mechanism and its temporal evolution in future observations.
基金supported by the National Natural Science Foundation of China(21971246,22371108,22075122)Taishan Scholar Foundation of Shandong Province(tsqn202211242)the Chunhui Program of the Ministry of Education of China(HZKY20220463).
文摘The potential application of gold nanoparticles(GNPs)in biomedicine has been extensively reported.However,there is still too much puzzle about their real face and potential health risks in comparison with the commercial drug molecules.The emergence of atomically precise gold nanoclusters(APGNCs)provides the opportunity to address the puzzle due to their ultrasmall size,defined molecular formula,editable surface engineering,available structures and unique physicochemical properties including excellent biocompatibility,strong luminescence,enzyme-like activity and efficient renal clearance,et al.Recently,these advantages of APGNCs also endow them promising performances in healthcare such as bioimaging,drug delivery,antibacterial and cancer therapy.Especially,their clear composition and structures like the commercial drug molecules facilitate the study of their functions and the structure-activity relationship in healthcare,which is essential for the guided design of APGNC nanomedicine.Therefore,this review will focus the advantages and recent progress of APGNCs in health care and envision their prospects for the future.
基金Supported by the National Natural Science Foundation of China(21476119,21406124)Major Science and Technology Innovation Project of Shandong Province(2018CXGC1102).
文摘The amount of low-temperature heat generated in industrial processes is high,but recycling is limited due to low grade and low recycling efficiency,which is one of the reasons for low energy efficiency.It implies that there is a great potential for low-temperature heat recovery and utilization.This article provided a detailed review of recent advances in the development of low-temperature thermal upgrades,power generation,refrigeration,and thermal energy storage.The detailed description will be given from the aspects of system structure improvement,work medium improvement,and thermodynamic and economic performance evaluation.It also pointed out the development bottlenecks and future development trends of various technologies.The low-temperature heat combined utilization technology can recover waste heat in an all-round and effective manner,and has great development prospects.
基金supported by the National Natural Science Foundation of China (No. 21101097)Natural Science Foundation of Shandong Province (ZR2010BQ023)the State Key Laboratory of Solid Lubrication (No. 0701)
文摘Solvothermal reactions of 3,5-dimethyl-2,6-bis(3-(pyrid-2-yl)-1,2,4-triazolyl) pyridine (L), 1,4-benzendicarboxylic acid (H2bdc), and transitional metal cations of M11 (M = Mn, Co, Cd) in the presence of oxalic acid (H2ox) afford three novel supramolecular polymers (CPs), namely, {[M2(ox)(L)2][bdc][M2(Hox)2(OH)(H2O)4]·3H2O}n (M = Mn for 1, Co for 2, Cd for 3). Single-crystal X-ray diffraction analysis reveals that complexes 1-3 are isostructural and the 3D supramolecular structure was connected through non-covalent interactions. With the help of H2ox, the L ligands cheated with center atoms forming a butterfly [M2(ox)(L)2]2+ building block. The bdc2- ligand linked with the unprecedented [M2(Hox)2(OH)2(H2O)4] units through strong O-H...O hydrogen bonds forming a zigzag chain, which are further connected through π-π interactions between L and bdc2- ligands to form a 3D supramolecular structure. Moreover, elemental analyses, IR, thermogravimetric, PXRD and luminescence have been investigated.
基金supported by Financial support from the Natural Science Foundation of Shandong (BR2010BQ023) and Qilu Normal University
文摘One novel copper(II)-organic compound,namely Cu[Cu2(PP)2](CBPC)2]·2(H2O)(1,H2CBPC = 1-[(2'-carboxybiphenyl-4-yl)methyl]-2-propylimidazole-4-carboxylic acid,HPP = 3-(2-pyridyl)pyrazole),was designed and synthesized under hydrothermal conditions.X-ray diffraction analysis reveals that two Cu(II)ions in the quasi-planar dimmer of [Cu2(PP)2] are linked by the carboxylate oxygen atoms on the phenyl ring and the imidazole ring,respectively,yielding one snake-shaped structure.Magnetic measurements reveal that compound 1 shows the strongly antiferromagnetic property.Crystal data of 1:C58H52Cu3N10O10,Mr = 1239.72,monoclinic,P21/c,a = 14.900(7),b = 15.029(7),c = 12.308(6),β = 102.519(9)o,V = 2691(2)3,Z = 2,Dc = 1.530 g/cm3,F(000)= 1274,μ = 1.246 mm-1,R = 0.0416,wR = 0.0780(I 2σ(I))and S = 0.999.
基金Supported by the National Natural Science Foundation of China(20873150)Natural Science Foundation of Shandong Province(ZR2010BQ023)
文摘Two new coordination polymers,[Zn(bdc)(1,3-bimb)]n(1) and {[Mn2(ox)2(1,3,5tib)4/3]·4H2O}n(2)(H2ox = oxalic acid,H2bdc = terephthalic acid,1,3-bimb = 1,3-bis(imidazol-1ylmethyl)benzene,1,3,5-tib = 1,3,5-tri(imidazol-1-yl)benzene),were synthesized and characterized by elemental analysis,IR,powder X-ray diffraction(PXRD),and thermogravimetric(TG) analyses.X-ray diffracation analysis reveals that two kinds of zigzag chains [Zn(bdc)]n and [Zn(1,3-bimb)]n in compound 1 are interweaved to form a 3D 4-fold interpenetrated 66-dia framework.In compound 2,Mn(1) and Mn(2) are linked via 1,3,5-tib ligands to form two different nets of [Mn6(1,3,5-tib)6 ]n along the ab plane with inner-or outer-shape N–Mn–N angles,which are connected by 1D infinite [Mn2(ox)2 ]n chains via Mn–O bonds to result in a(3,3,3,4,4)-connected(4·8·10)3(4·82)3(4·83·102)6(82·104·3)3(83)4 topology.Moreover,the photoluminescence of 1 has been investigated.The crystal of 1 crystallizes in orthorhombic,space group Pna2 with a = 13.2267(6),b = 9.1717(4),c = 17.4492(8),V = 2116.79(16)3,Z = 4,C22 H18N4O4 Zn,Mr = 467.77,Dc = 1.468 g/cm3,F(000) = 960 and μ(MoKα) = 1.197 mm-1.The final R = 0.0280 and wR = 0.0618 for 3695 observed reflections with I 2(I) and R = 0.0389 and wR = 0.0653 for all data.The crystal of 2 crystallizes in rhombohedral,space group R-3 with a = 22.080(8),c = 31.19(2),V = 13167(11) 3,Z = 18,C24 H25 Mn2 N8 O13,Mr = 743.40,Dc = 1.688 g/cm3,F(000) = 6822 and μ(MoKα) = 0.945 mm-1.The final R = 0.0429 and wR = 0.1035 for 5160 observed reflections with I 2(I) and R = 0.0824 and wR = 0.1244 for all data.
基金supported by the National Natural Science Foundation of China(20873150)the Natural Science Foundation of Shandong Province(ZR2010BQ023)
文摘One novel cobalt coordination polymer, {[Co(HTCB)(4,4'btb)]'HzO}n (1, H3TCB = 1,3,5-tris(4-carboxyphenyl)benzene, 4,4'-btb = 4,4'-bis(1,2,4-triazol-3-yl)biphenyl), has been synthesized and characterized by elemental analysis, IR, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. X-ray diffraction analysis reveals that complex 1 is a 2D 2-fold interpenetrated {44,62}-sql [Co(HTCB)(4,4'-btb)] sheet based on the 1D [Co(HTCB)]n chains and 1D [Co(4,4'-btb)]n chains. The crystal of 1 crystallizes in triclinic, space group P1 with a = 9.529(12), b = 13.914(16), c = 14.906(17) A, V= 1903(4) A3, Z = 2, C45H34N6CoO71 Mr= 829.71, Dc = 1.448 g/cm3, F(000) = 858 andμ(MoKa) = 0.514 mm-1. The final R = 0.0655 and wR = 0.1136 for 6603 observed reflections with 1 〉 2a(/) and R = 0.1136 and wR = 0.1747 for all data.
基金financial supports provided by the National Natural Science Foundation of China (21871164)the Taishan Scholar Project Foundation of Shandong Province (ts20190908, ts201511004)the Natural Science Foundation of Shandong Province (ZR2019MB024)。
文摘Titanium dioxide(TiO_2) has been investigated broadly as a stable,safe,and cheap anode material for sodium-ion batteries in recent years.However,the poor electronic conductivity and inherent sluggish sodium ion diffusion hinder its practical applications.Herein,a self-template and in situ vulcanization strategy is developed to synthesize self-supported hybrid nanotube arrays composed of nitrogen/sulfur-codoped carbon coated sulfur-doped TiO_2 nanotubes(S-TiO_2@NS-C) starting from H_2 Ti_2 O_5-H_2 O nanoarrays.The S-TiO_2@NS-C composite with one-dimensional nano-sized subunits integrates several merits.Specifically,sulfur doping strongly improves the Na~+ storage ability of TiO_2@C-N nanotubes by narrowing the bandgap of original TiO_2.Originating from the nanoarrays structures built from hollow nanotubes,carbon layer and sulfur doping,the sluggish Na~+ insertion/extraction kinetics is effectively improved and the volume variation of the electrode material is significantly alleviated.As a result,the S-TiO_2@NS-C nanoarrays present efficient sodium storage properties.The greatly improved sodium storage performances of S-TiO_2@NS-C nanoarrays confirm the importance of rational engineering and synthesis of hollow array architectures with higher complexity.
基金supported by the National Natural Science Foundation of China (20873163)the Natural Science Foundation of Shandong Province (BR2010BQ023)+1 种基金Shandong Provincial Education Department (J09LB55)Qilu Normal University
文摘One novel entangled cobalt compound, {[Co3(nbta)2(4,4'-bpy)2(H2O)2](H2O)2}n (1, H3nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, 4,4'-bpy = 4,4'-bipyridyl), was prepared and characterized by X-my diffraction, magnetism, elemental analysis, XPS, TGA and IR spectroscopy. The crystal of 1 crystallizes in monoclinic, space group Pc with a = 13.0717(16), b = 11.4167(14), c = 15.9342(19) A, β = 90.5190(10)°, V= 2377.9(5) A3, Z= 2, C48H36Co3N8O20, Mr = 1221.64, Dc = 1.706 g/cm3, F(000) = 1242 and μ(MoKa) = 1.128 mm^-1. The final R = 0.0497 and wR = 0.1461 for 4185 observed reflections with I 〉 20(0 and R = 0.0721 and wR = 0.1619 for all data. X-ray diffraction analyses revealed that Co(l) is linked by the nbta3- ligands to form the ladder shape along the c axis, which is further extended into two-dimensional networks via the joint of Co(2) along the a axis. Moreover, these two dimensional motifs are interconnected by the 4,4'-bpy bridges to form a complicated 3-D polymeric framework. Magnetic measurements revealed that compound 1 shows strong antiferromagnetic property.
基金supported by the National Natural Science Foundation of China(20873150)the Natural Science Foundation of Shandong Province(ZR2010BL012,ZR2010BQ023)
文摘Hydrothermal reactions of two imidazole derivatives (1,3,5-tib = 1,3,5-tris(1H- imidazol- 1 -yl)benzene, 1,4-bimb = 1,4-bis(1 H-imidazol- 1 -ylmethyl)benzene) and the ZnⅡ cations in the presence of oxalic acid (H2ox) afford two coordination polymers, namely, {[Zn(ox)(1,3,5- tib)]·2(H20)}n (1) and [Znl.5(OX)1.5(1,4-bimb)l.5]n (2). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction (PXRD) analyses. Both complexes 1 and 2 are based on the 1D zigzag [Zn(ox)]n chains, and their final structures are controlled by the two different imidazole linkers, which expanded the structure along different directions, finally giving a 3D dia net for 1 and a 2D sql layer for 2. Moreover, the luminescent properties of 1 and 2 have been investigated.