A novel method for synthesis of substituted u-oxo-bis[tetraphenyl porphyrinatoiron] compotmds （[TRPPFe]20） based on the reaction among free base porphyrins （TRPPH2）, FeSO4·7H2O and H2O in one pot was proposed...A novel method for synthesis of substituted u-oxo-bis[tetraphenyl porphyrinatoiron] compotmds （[TRPPFe]20） based on the reaction among free base porphyrins （TRPPH2）, FeSO4·7H2O and H2O in one pot was proposed and investigated. Four kinds of [TRPPFe]2O were synthesized by this novel synthetic method, and their structures were characterized by elemental analysis, infrared spectra and UV-vis spectroscopy. The reaction conditions, including the effect of different iron salts on the formation of [TRPPFe]2O, the reaction time between FeSO4-7H2O and TRPPH2, the molar ratio of FeSO4-7H2O/TRPPH2 as well as the volume ratio of H2O/DMF, were investigated. The [TRPPFe]2O yield of 93% 98% could be obtained under the following optimal conditions： the reaction time of FeSOn-7H2O with TRPPH2 was about 10 h, the molar ratio of FeSOn-7H2O/TRPPH2 about 5 ： 1, and the volume ratio of H2O/DMF exceeded 2 ： 1. Further research indicated that only TRPPFeCI were formed once FeSOn-7H2O was replaced by FeCl2-4H2O, the reason of which might be that halogen ions in iron salts interfered the formation of [TRPPFe]2O, suggesting that halogen ions should be avoided in this novel synthetic method.展开更多
The highly-dispersed iron element decorated Ni foam was prepared by simple immersion in a ferric nitrate solution at room temperature without using acid etching, and characterized by X-ray powder diffraction(XRD), sca...The highly-dispersed iron element decorated Ni foam was prepared by simple immersion in a ferric nitrate solution at room temperature without using acid etching, and characterized by X-ray powder diffraction(XRD), scanning electron microscopy(SEM), EDAX spectrum(EDAX mapping) and Raman spectroscopy. The EDAX spectrum illustrated that iron element was highly-dispersed over the entire surface of nickel foam, and the Raman spectroscopy revealed that both Ni-O and Fe-O bonds were formed on the surface of the as-prepared electrode. Moreover, the iron element decorated Ni foam electrode can be used as non-enzymatic glucose sensor and it exhibits not only an ultra-wide linear concentration range of 1-18 mmol/L with an outstanding sensitivity of 1.0388 m A·mmol/(L·cm2), but also an excellent ability of stability and selectivity. Therefore, this work presents a simple yet effective approach to successfully modify Ni foam as non-enzymatic glucose sensor.展开更多
All-inorganic perovskites CsPbX_(3)(X=Cl,Br,I)have attracted worldwide interest due to their excellent lumi-nescent performances.Meanwhile,Cs_(4)PbBr_(6) have been studied because they can enhance the luminescent effi...All-inorganic perovskites CsPbX_(3)(X=Cl,Br,I)have attracted worldwide interest due to their excellent lumi-nescent performances.Meanwhile,Cs_(4)PbBr_(6) have been studied because they can enhance the luminescent efficiency and stability of CsPbBr_(3).Herein,we introduced a microfluidic method based on room-temperature supersat-urated recrystallization to synthesize blue-emitting CsPbBr_(3)nanocrystals(NCs)and green-emitting CsPbBr_(3)/Cs_(4)PbBr_(6)NCs.The ultrasmall CsPbBr_(3)NCs emitted at a deep blue wavelength of 461 nm with the full width at half maximum(FWHM)of 15 nm.transmission electron microscopy(TEM)results demonstrated that ultrasmall CsPbBr_(3)NCs with the average particle size of 3.8 nm were synthesized and the CsPbBr_(3)NCs were crystallized as monoclinic structure.展开更多
Nitrogen oxide(NO_(x))is one of the most critical contaminants in the air,and the control of NO_(x)emission from diesel vehicles is very important.Cu-based small-pore zeolites have already been applied for NO_(x)abate...Nitrogen oxide(NO_(x))is one of the most critical contaminants in the air,and the control of NO_(x)emission from diesel vehicles is very important.Cu-based small-pore zeolites have already been applied for NO_(x)abatement on diesel vehicles.Among the small-pore zeolites,Cu-SSZ-50 catalysts with good NH_(3)-SCR catalytic activity were believed to have potential for application.In this study,a one-pot synthesis method for Cu-SSZ-50 catalysts was developed for the first time,using the co-templates of Cu-TEPA and 2,6-dimethyl-N-methylpyridinium hydroxide.In this synthesis method,Cu-SSZ-50 with various Cu contents can be obtained by adjusting the amount of Cu-TEPA without the need for a further after-treatment process.The addition of Cu-TEPA affected the framework atoms and Cu species,and a lower Si/Al ratio and more SCR active Cu species were obtained.The synthesized catalyst with a Cu/Al ratio of 0.40 exhibited over 90%NO_(x)conversion between 200℃and 450℃for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).Meanwhile,over 80%NO_(x)conversion could be obtained from 250℃to 450℃after hydrothermal aging at 750℃for 16 h.In addition,both L-H and E-R mechanisms were proven to exist for the one-pot-synthesized Cu-SSZ-50 by in situ DRIFTS experiments.The simple synthesis procedure,excellent catalytic activity and hydrothermal stability brighten the prospects for the application of Cu-SSZ-50.展开更多
A mild, one-pot procedure for the synthesis of vinyl ethers in good yields from 2-hydroxyalkyl phenyl selenides with primary or secondary organic halides has been developed.
Three new multi-step one-pot processes for high-yielding cyclohexanecarbonitrile synthesis starting from cyclohexanone were developed for industrial application. In contrast to the current synthetic process, all of th...Three new multi-step one-pot processes for high-yielding cyclohexanecarbonitrile synthesis starting from cyclohexanone were developed for industrial application. In contrast to the current synthetic process, all of the processes described were designed to proceed completely in methanol as a uniform solvent and the key oxidation step can be realized either as stoichiometric or catalytic. Atom efficiency of processes is relatively advanced with high regioselectivity, reaction by-products are either from environmental pool—carbon dioxide and nitrogen—or they can be reused—sodium chloride. Solvent—methanol—and other auxiliaries—cyclohexane, copper catalyst—can be reused after recycling as well. EcoScale for all three designed processes was evaluated and compared with current synthesis described in the past. Green chemistry metrics, including newly introduced evaluative tool—Sustainability Index of the Synthesis (SIS), were applied to evaluate design of described one-pot syntheses.展开更多
The generation and manipulation of spin-polarized electrons at room temperature are essential for the development of advanced spin-optoelectronic devices.In this work,a one-pot method was used to successfully synthesi...The generation and manipulation of spin-polarized electrons at room temperature are essential for the development of advanced spin-optoelectronic devices.In this work,a one-pot method was used to successfully synthesize homogenous Mn:CsPbBr_(3) perovskite quantum dots in air with particle sizes of 7−8 nm.The effects of Mn doping on the structure,optical and magnetic properties of CsPbBr_(3) quantum dots were investigated.The findings demonstrated proper Mn doping improved the crystallinity and photoluminescence(PL)of quantum dots.The prepared quantum dots have a narrow full width at half maximum emission(FWHM)of about 17−20 nm.The magnetic properties of the doped samples and the effect of the magnetic field on the PL spectra properties were analyzed.The results show that trace Mn doping can improve the room-temperature ferromagnetism of CsPbBr_(3) quantum dots.Doping with magnetic elements makes CsPbBr_(3) quantum dots more responsive to the applied magnetic field.Even at a lower 50 mT magnetic field,the PL peak of Mn:CsPbBr_(3) still declined 5.91%.Mn:CsPbBr_(3) quantum dots are a new type of multifunctional material that is beneficial to spintronics research.This work demonstrates a low-cost synthesis method.It should make all-inorganic perovskite quantum dots a promising material for room-temperature spin optoelectronic devices.展开更多
The study explores the feasibility of producing ruthenium catalysts supported on char through a one-pot synthesis,an original approach for the preparation of noble metal-based catalysts in this field.This method combi...The study explores the feasibility of producing ruthenium catalysts supported on char through a one-pot synthesis,an original approach for the preparation of noble metal-based catalysts in this field.This method combines high-temperature stages,such as catalytic support carburization and catalyst activation,in a single step.The innovation represents a significant advancement in utilizing cellulose as a model of waste biomass,enhancing its value,and reducing catalyst production costs.The one-pot catalysts were successfully tested in the hydrogenation reaction of sugar mixtures(L-Arabinose and D-Galactose)under mild conditions,achieving full selectivities.The research also introduces for the first time in that reaction a structural sensitivity analysis of the reaction,comparing experimental results with a theoretical model.The findings reveal a direct correlation between catalytic activity and the{0001}exposed face of hcp ruthenium nanoclusters.This discovery opens new avenues for industrial-scale catalyst development,promising substantial reductions in energy and production costs,and emphasizing the economic appeal of the process.展开更多
Nonlinear Rossby waves are used to describe typical wave phenomena in large-scale atmosphere andocean.Owing to the nonlinearity of the involved problems,the weakly nonlinear method,ie the derivative ex-pansion method,...Nonlinear Rossby waves are used to describe typical wave phenomena in large-scale atmosphere andocean.Owing to the nonlinearity of the involved problems,the weakly nonlinear method,ie the derivative ex-pansion method,was mainly used to investigate Rossby waves under the combined effects of the generalizedβ-effect and the basic flow effect.The derivative expansion method has the advantage of capturing the multi-scalecharacteristics of wave processes simultaneously.In the case where the perturbation expansion is independentof secular terms,the nonlinear equations describing the amplitude evolution of nonlinear waves were derived,such as the Korteweg-de Vries equation,the Boussinesq equation and Zakharov-Kuznetsov equation.Both quali-tative and quantitative analyses indicate that the generalizedβ-effect is the key factor inducing the evolution ofRossby solitary waves.展开更多
SiC/Al-based composite foams were prepared by a two-step foaming method.The influence of the SiC content and its distribution uniformity on the foaming stability,cell structure,and mechanical properties of the aluminu...SiC/Al-based composite foams were prepared by a two-step foaming method.The influence of the SiC content and its distribution uniformity on the foaming stability,cell structure,and mechanical properties of the aluminum foams was investigated.The macro/micro-features of the aluminum foams were characterized and analyzed.Results demonstrate that an appropriate increase in SiC content and the uniform distribution of SiC can improve the foaming stability,optimize the cell diameter and cell wall thickness,ameliorate the cell distribution,and enhance the hardness and compressive strength of the aluminum foams.However,either insufficient or excessive SiC leads to uneven distribution of SiC particles,which is unfavorable to foaming stability and good cell structure formation.With 6wt%SiC,both the foaming stability and cell structure of the aluminum foam reach the optimal state,resulting in the highest compressive strength and optimal energy absorption capacity.展开更多
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ...In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method.展开更多
This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SE...This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SEM),which is used to simulate low-frequency ground motion(f<1 Hz)by incorporating an innovative efficient discontinuous Galerkin(DG)method for grid division to accurately model basin sedimentary layers at reduced costs.It also introduces a comprehensive hybrid source model for high-frequency random scattering and a nonlinear analysis module for basin sedimentary layers.Deterministic outcomes are combined with modified three-dimensional stochastic finite fault method(3D-EXSIM)simulations of high-frequency ground motion(f>1 Hz).A fourth-order Butterworth filter with zero phase shift is employed for time-domain filtering of low-and high-frequency time series at a crossover frequency of 1 Hz,merging the low and high-frequency ground motions into a broadband time series.Taking an Ms 6.8 Luding earthquake,as an example,this hybrid method was used for a rapid and efficient simulation analysis of broadband ground motion in the region.The accuracy and efficiency of this hybrid method were verified through comparisons with actually observed station data and empirical attenuation curves.Deterministic method simulation results revealed the effects of mountainous topography,basin effects,nonlinear effects within the basin’s sedimentary layers,and a coupling interaction between the basin and the mountains.The findings are consistent with similar studies,showing that near-fault sedimentary basins significantly focus and amplify strong ground motion,and the soil’s nonlinear behavior in the basin influences ground motion to varying extents at different distances from the fault.The mountainous topography impacts the basin’s response to ground motion,leading to barrier effects.This research provides a scientific foundation for seismic zoning,urban planning,and seismic design in nearfault mountain basin regions.展开更多
This study systematically conducted preparation optimization and performance investigations on Co-modified Ce/TiO_(2) catalysts,with a focus on examining how preparation methods and Co loading regulate the catalyst’s...This study systematically conducted preparation optimization and performance investigations on Co-modified Ce/TiO_(2) catalysts,with a focus on examining how preparation methods and Co loading regulate the catalyst’s low-temperature denitrification activity.After identifying optimal preparation parameters via condition screening,multiple characterization techniques-including BET,XRD,XPS,H_(2)-TPR and in situ DRIFTS-were employed to deeply analyze the catalyst’s physicochemical properties and reaction mechanism.Results demonstrated that compared to the impregnation and co-precipitation methods,the Ce-Co_(0.025)/TiO_(2)-SG catalyst(prepared by the sol-gel method with a Co/Ti mass ratio of 0.025)exhibited significantly superior denitrification activity:NO conversion remained stably above 95%in the 225−350℃ temperature range,and it displayed high N_(2) selectivity.Characterization analysis revealed that abundant surface oxygen vacancies,a high proportion of Ce^(3+) species,and prominent acidic sites collectively contributed to enhancing its low-temperature denitrification performance.This work provides reference value for the development of highly efficient low-temperature denitrification catalysts.展开更多
Herein,one-pot chemocatalytic conversion of xylose to value-added C_(5)/C_(4) cyclic ethers over a novel ZrO_(2)-doped Ni-Pd catalyst supported on H-βzeolite was demonstrated.Optimized catalyst,namely,Ni_(2) Pd_(0.5)...Herein,one-pot chemocatalytic conversion of xylose to value-added C_(5)/C_(4) cyclic ethers over a novel ZrO_(2)-doped Ni-Pd catalyst supported on H-βzeolite was demonstrated.Optimized catalyst,namely,Ni_(2) Pd_(0.5)Zr_(1)/H-β(25),achieved a high xylose transformation(>99%)with high selectivities toward 2-methyltetrahydrofuran(48.6%)and tetrahydropyran(20.2%)under mild reaction conditions(200℃,1.0 MPa H_(2),and 2 h).Systematic investigation of the physicochemical properties of the catalyst revealed that ZrO_(2) doping induced O vacancies,enhanced H_(2) activation,and improved metal dispersion,thereby promoting hydrogenation and hydrodeoxygenation.In situ diffuse reflectance infrared Fourier transform spectroscopy using furfural and furfuryl alcohol probes confirmed preferential adsorption geometries and electronic interactions at metal-ZrO_(2) interfaces.Time-resolved and feedstock variation studies further elucidated the reaction mechanism and highlighted the roles of key intermediates.The proposed catalyst exhibited excellent recyclability with only a minor decline in performance after multiple xylose conversion cycles.This study provides mechanistic insights and design principles for the development of efficient multifunctional catalysts for biomass valorization.展开更多
[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and pun...[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and puncture,the index data of the fruit were obtained by setting different trigger forces,deformation levels,test speeds,as well as puncture speeds and puncture depths.The data included TPA hardness,adhesiveness,springiness,cohesiveness,gumminess,chewiness,resilience,as well as skin hardness,skin toughness,flesh hardness,fracturability,and compactness.[Results]Different deformation levels had a significant impact on all parameters.Hardness,adhesiveness,gumminess and chewiness showed a trend of first increasing and then decreasing with the deformation level increasing.When the deformation level was 30%,the adhesiveness,gumminess and chewiness reached their maximum values.When the deformation level was 50%,TPA hardness reached its maximum.When the compression speed was 3 mm/s,the measured values of TPA hardness,adhesiveness,chewiness,and resilience were at their maximums.The skin hardness varied significantly under different trigger forces.When the trigger force was 15 g,the skin hardness reached a maximum value of 944.63 g,and the skin toughness,flesh hardness,fracturability,and compactness also reach their maximum values respectively.When the puncture depth was 12 mm,the flesh hardness and skin toughness reached their maximums of 682.51 g and 1.82 mm,respectively.In the TPA mode,the flesh hardness of chieh-qua showed an extremely significant negative correlation with springiness,cohesiveness,and resilience(P<0.01).The fruit fracturability detected by puncture had an extremely significant positive correlation with compactness(P<0.01).[Conclusions]The evaluation method for measuring chieh-qua texture by combining TPA and the puncture mode could accurately and quantitatively reflect the differences in the flesh texture quality of chieh-qua.The optimal parameters for texture measurement of chieh-qua fruit were determined as a 15 g trigger force with 50%deformation and a 3 mm/s compression speed in TPA mode,and a 15 g trigger force with a 12 mm puncture depth in puncture mode.Puncture speed was found to have no significant effect on the texture indices of chieh-qua.展开更多
The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometr...The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometric distortions, leading to a diminution in the predictive accuracy of the distorted similitude. To address this challenge, this study formulates a novel set of scaling laws, tailored to account for the intricate geometric distortions associated with elastic rings. The proposed scaling laws are formulated based on the intrinsic deformation characteristics of elastic rings, rather than the traditional systemic governing equations. Numerical and experimental cases are conducted to assess the efficacy and precision of the proposed scaling laws, and the obtained results are compared with those achieved by traditional methods. The outcomes demonstrate that the scaling laws put forth by this study significantly enhance the predictive capabilities for deformations of elastic rings.展开更多
This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,Calcu...This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,CalculiX,and preCICE to simulate fluid-particle-structure interactions with large deformations.Mesh motion in the fluid field is handled using the radial basis function(RBF)method.The particle phase is modeled by MPPIC,where fluid-particle interaction is described through momentum exchange,and inter-particle collisions are characterized by collision stress.The structural field is solved by nonlinear FEM to capture large deformations induced by geometric nonlinearity.Coupling among fields is realized through a partitioned,parallel,and non-intrusive iterative strategy,ensuring stable transfer and convergence of interface forces and displacements.Notably,the influence of particles on the structure is not direct but mediated by the fluid,while structural motion directly affects particle dynamics.The results demonstrate that the proposed approach effectively captures multiphysics interaction processes and provides a valuable reference for numerical modeling of coupled fluid-particle-structure systems.展开更多
As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency...As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency of exciton utilization and the overall performance of organic light-emit-ting devices are closely linked to the singlet-triplet energy gap(ΔE_(ST))of MR-TADF emitters.Identifying an economic and accu-rate theoretical approach to predictΔE_(ST)would be beneficial for high-throughput screening and facilitate the inverse design of MR-TADF molecules.In this study,we evaluated the S_(1)state energy(E(S_(1))),T_(1)state ener-gy(E(T_(1))),andΔE_(ST)using three different physical interpretations:adiabatic excitation ener-gy,vertical absorption energy,and vertical emission energy.We employed the time-depen-dent density functional theory(TDDFT)and delta self-consistent field(ΔSCF)methods to calculate E(S_(1)),E(T_(1)),andΔE_(ST)for 20 MR-TADF molecules reported in the literature.We compared these calculated values with experimental data obtained from fluorescence spec-troscopy at room-temperature(or 77 K)and phosphorescence spectroscopy conducted at 77 K.Our findings indicate that the vertical absorption energy at the S0 state minimum,deter-mined by theΔSCF method,accurately predicts the S_(1)state energy.Similarly,the vertical absorption energy at the S0 state minimum,calculated using the TDDFT method,effectively predicts the T_(1)state energy.TheΔE_(ST)derived from the difference between these two excita-tion energies exhibited the smallest mean absolute error of only 0.039 eV compared to the ex-perimental values.This combination represents the most accurate and cost-effective method reported to date for predicting theΔE_(ST)of MR-TADF molecules,and can be integrated into AI-driven inverse design workflows for new emitters.展开更多
In a multiple voltage source converter(VSC)system,the nonlinear characteristics of phase-locked loops(PLLs)and their interactions have a significant influence on the synchronization stability of converters.In this pap...In a multiple voltage source converter(VSC)system,the nonlinear characteristics of phase-locked loops(PLLs)and their interactions have a significant influence on the synchronization stability of converters.In this paper,these influences are investigated from the perspective of the time domain.First,a novel time-domain model of the multi-VSC system is obtained by using a multi-scale method.On this basis,a stability criterion is proposed to assess the synchronization stability of the system.Then,the accuracy of the time-domain model and its stability criterion in various conditions are discussed.Moreover,the negative impact of the interaction on the system is quantified.Finally,the above theoretical analysis is also verified in the controller hardware-in-the-loop(CHIL)experiments.展开更多
Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of...Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of informing the optimization of disclosure processes and meeting the communication needs of affected families.Methods In accordance with the Joanna Briggs Institute(JBI)methodology for mixed methods systematic reviews,the convergent segregated approach was used in this review.Articles were retrieved from 11 databases,including PubMed,Web of Science,CINAHL,CENTRAL,Embase,Ovid/Medline,PsycINFO,PsycArticles,Scopus,ERIC,and China National Knowledge Infrastructure(CNKI).The quality of the selected articles was assessed using the Mixed Method Appraisal Tool(MMAT).The review protocol was registered on PROSPERO(CRD42024542746).Results A total of 21 studies from 10 countries were included.Their methodological quality was generally medium to high,with MMAT scores ranging from 60%to 100%.The synthesis yielded three core themes:1)the spectrum of professional and societal attitudes toward disclosure;2)the dynamic practices of navigating disclosure amid uncertainty,including timing and environment,stakeholders,and content of disclosure;and 3)factors influencing disclosure,including children’s,parental,healthcare professionals’,and socio-cultural factors.Conclusions This review synthesized the perspectives and experiences of healthcare professionals regarding disclosure in childhood cancer,highlighting the complexity and multidimensional nature of this process in clinical practice.Future research should further investigate the experiences and needs of children and their parents,explore cultural variations in disclosure practices,develop context-appropriate assessment tools,and construct multidimensional intervention strategies to enhance the humanistic care and professional effectiveness of the disclosure process.展开更多
基金Supported by the National Natural Science Foundation of China （20776003, 20576005） and the Key Project of Natural Science Foundation of Beijing （2061001）.
文摘A novel method for synthesis of substituted u-oxo-bis[tetraphenyl porphyrinatoiron] compotmds （[TRPPFe]20） based on the reaction among free base porphyrins （TRPPH2）, FeSO4·7H2O and H2O in one pot was proposed and investigated. Four kinds of [TRPPFe]2O were synthesized by this novel synthetic method, and their structures were characterized by elemental analysis, infrared spectra and UV-vis spectroscopy. The reaction conditions, including the effect of different iron salts on the formation of [TRPPFe]2O, the reaction time between FeSO4-7H2O and TRPPH2, the molar ratio of FeSO4-7H2O/TRPPH2 as well as the volume ratio of H2O/DMF, were investigated. The [TRPPFe]2O yield of 93% 98% could be obtained under the following optimal conditions： the reaction time of FeSOn-7H2O with TRPPH2 was about 10 h, the molar ratio of FeSOn-7H2O/TRPPH2 about 5 ： 1, and the volume ratio of H2O/DMF exceeded 2 ： 1. Further research indicated that only TRPPFeCI were formed once FeSOn-7H2O was replaced by FeCl2-4H2O, the reason of which might be that halogen ions in iron salts interfered the formation of [TRPPFe]2O, suggesting that halogen ions should be avoided in this novel synthetic method.
基金Project(2019zzts684)supported by the Fundamental Research Funds for the Central Universities,China。
文摘The highly-dispersed iron element decorated Ni foam was prepared by simple immersion in a ferric nitrate solution at room temperature without using acid etching, and characterized by X-ray powder diffraction(XRD), scanning electron microscopy(SEM), EDAX spectrum(EDAX mapping) and Raman spectroscopy. The EDAX spectrum illustrated that iron element was highly-dispersed over the entire surface of nickel foam, and the Raman spectroscopy revealed that both Ni-O and Fe-O bonds were formed on the surface of the as-prepared electrode. Moreover, the iron element decorated Ni foam electrode can be used as non-enzymatic glucose sensor and it exhibits not only an ultra-wide linear concentration range of 1-18 mmol/L with an outstanding sensitivity of 1.0388 m A·mmol/(L·cm2), but also an excellent ability of stability and selectivity. Therefore, this work presents a simple yet effective approach to successfully modify Ni foam as non-enzymatic glucose sensor.
基金the National Frontier Technology Key R&D Project(Nos.XXX-125 and JXXX-2019-058)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Collaborative Innovation Center of Advanced Inorganic Functional Composites of Jiangsu Province。
文摘All-inorganic perovskites CsPbX_(3)(X=Cl,Br,I)have attracted worldwide interest due to their excellent lumi-nescent performances.Meanwhile,Cs_(4)PbBr_(6) have been studied because they can enhance the luminescent efficiency and stability of CsPbBr_(3).Herein,we introduced a microfluidic method based on room-temperature supersat-urated recrystallization to synthesize blue-emitting CsPbBr_(3)nanocrystals(NCs)and green-emitting CsPbBr_(3)/Cs_(4)PbBr_(6)NCs.The ultrasmall CsPbBr_(3)NCs emitted at a deep blue wavelength of 461 nm with the full width at half maximum(FWHM)of 15 nm.transmission electron microscopy(TEM)results demonstrated that ultrasmall CsPbBr_(3)NCs with the average particle size of 3.8 nm were synthesized and the CsPbBr_(3)NCs were crystallized as monoclinic structure.
基金financially supported by the National Natural Science Foundation of China(Nos.52200136,52225004 and 51978640)the Science and Technology Innovation“2025”major program in Ningbo(No.2020Z103)。
文摘Nitrogen oxide(NO_(x))is one of the most critical contaminants in the air,and the control of NO_(x)emission from diesel vehicles is very important.Cu-based small-pore zeolites have already been applied for NO_(x)abatement on diesel vehicles.Among the small-pore zeolites,Cu-SSZ-50 catalysts with good NH_(3)-SCR catalytic activity were believed to have potential for application.In this study,a one-pot synthesis method for Cu-SSZ-50 catalysts was developed for the first time,using the co-templates of Cu-TEPA and 2,6-dimethyl-N-methylpyridinium hydroxide.In this synthesis method,Cu-SSZ-50 with various Cu contents can be obtained by adjusting the amount of Cu-TEPA without the need for a further after-treatment process.The addition of Cu-TEPA affected the framework atoms and Cu species,and a lower Si/Al ratio and more SCR active Cu species were obtained.The synthesized catalyst with a Cu/Al ratio of 0.40 exhibited over 90%NO_(x)conversion between 200℃and 450℃for the selective catalytic reduction of NO_(x)with NH_(3)(NH_(3)-SCR).Meanwhile,over 80%NO_(x)conversion could be obtained from 250℃to 450℃after hydrothermal aging at 750℃for 16 h.In addition,both L-H and E-R mechanisms were proven to exist for the one-pot-synthesized Cu-SSZ-50 by in situ DRIFTS experiments.The simple synthesis procedure,excellent catalytic activity and hydrothermal stability brighten the prospects for the application of Cu-SSZ-50.
基金the Natural Science Foundation of Jiangxi Province(No.0420017)for financial support
文摘A mild, one-pot procedure for the synthesis of vinyl ethers in good yields from 2-hydroxyalkyl phenyl selenides with primary or secondary organic halides has been developed.
文摘Three new multi-step one-pot processes for high-yielding cyclohexanecarbonitrile synthesis starting from cyclohexanone were developed for industrial application. In contrast to the current synthetic process, all of the processes described were designed to proceed completely in methanol as a uniform solvent and the key oxidation step can be realized either as stoichiometric or catalytic. Atom efficiency of processes is relatively advanced with high regioselectivity, reaction by-products are either from environmental pool—carbon dioxide and nitrogen—or they can be reused—sodium chloride. Solvent—methanol—and other auxiliaries—cyclohexane, copper catalyst—can be reused after recycling as well. EcoScale for all three designed processes was evaluated and compared with current synthesis described in the past. Green chemistry metrics, including newly introduced evaluative tool—Sustainability Index of the Synthesis (SIS), were applied to evaluate design of described one-pot syntheses.
基金supported by the Hubei province Natural Science Fund for Distinguished Young Scholars(No.201CFA077)Hubei province“Chu Tian Talent”scientific and technological innovation team.
文摘The generation and manipulation of spin-polarized electrons at room temperature are essential for the development of advanced spin-optoelectronic devices.In this work,a one-pot method was used to successfully synthesize homogenous Mn:CsPbBr_(3) perovskite quantum dots in air with particle sizes of 7−8 nm.The effects of Mn doping on the structure,optical and magnetic properties of CsPbBr_(3) quantum dots were investigated.The findings demonstrated proper Mn doping improved the crystallinity and photoluminescence(PL)of quantum dots.The prepared quantum dots have a narrow full width at half maximum emission(FWHM)of about 17−20 nm.The magnetic properties of the doped samples and the effect of the magnetic field on the PL spectra properties were analyzed.The results show that trace Mn doping can improve the room-temperature ferromagnetism of CsPbBr_(3) quantum dots.Doping with magnetic elements makes CsPbBr_(3) quantum dots more responsive to the applied magnetic field.Even at a lower 50 mT magnetic field,the PL peak of Mn:CsPbBr_(3) still declined 5.91%.Mn:CsPbBr_(3) quantum dots are a new type of multifunctional material that is beneficial to spintronics research.This work demonstrates a low-cost synthesis method.It should make all-inorganic perovskite quantum dots a promising material for room-temperature spin optoelectronic devices.
基金support for this work was obtained from Spanish Ministerio de Ciencia e Innovación(No.MCIN/AEI(10.13039/501100011033)/FEDER Funds una manera de hacer Europa)Project PID2020-113809RB-C32 and Junta de Andalucía via Consejería de EconómTransformación ica,Industria,Conocimiento y Universidades and its PAIDI 2020 program(No.P18-RT-3405)all co-financed by FEDER funds from the European Union.
文摘The study explores the feasibility of producing ruthenium catalysts supported on char through a one-pot synthesis,an original approach for the preparation of noble metal-based catalysts in this field.This method combines high-temperature stages,such as catalytic support carburization and catalyst activation,in a single step.The innovation represents a significant advancement in utilizing cellulose as a model of waste biomass,enhancing its value,and reducing catalyst production costs.The one-pot catalysts were successfully tested in the hydrogenation reaction of sugar mixtures(L-Arabinose and D-Galactose)under mild conditions,achieving full selectivities.The research also introduces for the first time in that reaction a structural sensitivity analysis of the reaction,comparing experimental results with a theoretical model.The findings reveal a direct correlation between catalytic activity and the{0001}exposed face of hcp ruthenium nanoclusters.This discovery opens new avenues for industrial-scale catalyst development,promising substantial reductions in energy and production costs,and emphasizing the economic appeal of the process.
文摘Nonlinear Rossby waves are used to describe typical wave phenomena in large-scale atmosphere andocean.Owing to the nonlinearity of the involved problems,the weakly nonlinear method,ie the derivative ex-pansion method,was mainly used to investigate Rossby waves under the combined effects of the generalizedβ-effect and the basic flow effect.The derivative expansion method has the advantage of capturing the multi-scalecharacteristics of wave processes simultaneously.In the case where the perturbation expansion is independentof secular terms,the nonlinear equations describing the amplitude evolution of nonlinear waves were derived,such as the Korteweg-de Vries equation,the Boussinesq equation and Zakharov-Kuznetsov equation.Both quali-tative and quantitative analyses indicate that the generalizedβ-effect is the key factor inducing the evolution ofRossby solitary waves.
基金Doctoral Startup Fund(20192066,20212028)Laijin Excellent Doctoral Fund(20202021)+1 种基金Scientific and Technological Innovation of Colleges and Universities in Shanxi Province(2020L0342)Fundamental Research Program of Shanxi Province(202303021222178)。
文摘SiC/Al-based composite foams were prepared by a two-step foaming method.The influence of the SiC content and its distribution uniformity on the foaming stability,cell structure,and mechanical properties of the aluminum foams was investigated.The macro/micro-features of the aluminum foams were characterized and analyzed.Results demonstrate that an appropriate increase in SiC content and the uniform distribution of SiC can improve the foaming stability,optimize the cell diameter and cell wall thickness,ameliorate the cell distribution,and enhance the hardness and compressive strength of the aluminum foams.However,either insufficient or excessive SiC leads to uneven distribution of SiC particles,which is unfavorable to foaming stability and good cell structure formation.With 6wt%SiC,both the foaming stability and cell structure of the aluminum foam reach the optimal state,resulting in the highest compressive strength and optimal energy absorption capacity.
基金Supported in part by Natural Science Foundation of Guangxi(2023GXNSFAA026246)in part by the Central Government's Guide to Local Science and Technology Development Fund(GuikeZY23055044)in part by the National Natural Science Foundation of China(62363003)。
文摘In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method.
基金National Natural Science Foundation of China under Grant Nos.U2139208 and 52278516Key Laboratory of Earthquake Engineering and Engineering Vibration,China Earthquake Administration under Grant No.2024D15Key Laboratory of Soft Soil Characteristic and Engineering Environment,Tianjin Chengjian University under Grant No.2022SCEEKL003。
文摘This study presents an effective hybrid simulation approach for simulating broadband ground motion in complex near-fault locations.The approach utilizes a deterministic approach based on the spectral element method(SEM),which is used to simulate low-frequency ground motion(f<1 Hz)by incorporating an innovative efficient discontinuous Galerkin(DG)method for grid division to accurately model basin sedimentary layers at reduced costs.It also introduces a comprehensive hybrid source model for high-frequency random scattering and a nonlinear analysis module for basin sedimentary layers.Deterministic outcomes are combined with modified three-dimensional stochastic finite fault method(3D-EXSIM)simulations of high-frequency ground motion(f>1 Hz).A fourth-order Butterworth filter with zero phase shift is employed for time-domain filtering of low-and high-frequency time series at a crossover frequency of 1 Hz,merging the low and high-frequency ground motions into a broadband time series.Taking an Ms 6.8 Luding earthquake,as an example,this hybrid method was used for a rapid and efficient simulation analysis of broadband ground motion in the region.The accuracy and efficiency of this hybrid method were verified through comparisons with actually observed station data and empirical attenuation curves.Deterministic method simulation results revealed the effects of mountainous topography,basin effects,nonlinear effects within the basin’s sedimentary layers,and a coupling interaction between the basin and the mountains.The findings are consistent with similar studies,showing that near-fault sedimentary basins significantly focus and amplify strong ground motion,and the soil’s nonlinear behavior in the basin influences ground motion to varying extents at different distances from the fault.The mountainous topography impacts the basin’s response to ground motion,leading to barrier effects.This research provides a scientific foundation for seismic zoning,urban planning,and seismic design in nearfault mountain basin regions.
基金Supported by the National Key Research and Development Program of China (2023YFB4102903)。
文摘This study systematically conducted preparation optimization and performance investigations on Co-modified Ce/TiO_(2) catalysts,with a focus on examining how preparation methods and Co loading regulate the catalyst’s low-temperature denitrification activity.After identifying optimal preparation parameters via condition screening,multiple characterization techniques-including BET,XRD,XPS,H_(2)-TPR and in situ DRIFTS-were employed to deeply analyze the catalyst’s physicochemical properties and reaction mechanism.Results demonstrated that compared to the impregnation and co-precipitation methods,the Ce-Co_(0.025)/TiO_(2)-SG catalyst(prepared by the sol-gel method with a Co/Ti mass ratio of 0.025)exhibited significantly superior denitrification activity:NO conversion remained stably above 95%in the 225−350℃ temperature range,and it displayed high N_(2) selectivity.Characterization analysis revealed that abundant surface oxygen vacancies,a high proportion of Ce^(3+) species,and prominent acidic sites collectively contributed to enhancing its low-temperature denitrification performance.This work provides reference value for the development of highly efficient low-temperature denitrification catalysts.
基金supported by the Bio&Medical Technology Development Program(no.RS-2022-NR067354)established by the National Research Foundation(NRF)funded by the Korean Ministry of Science and ICT(MSIT)+2 种基金an NRF grant funded by the Korean MSIT(no.RS-2023-00261322)Additional support from the Korea Institute of Energy Technology Evaluation and Planning(KETEP)the Ministry of Trade,Industry&Energy(MOTIE)of the Republic of Korea(RS-2024-00469587)was also appreciated。
文摘Herein,one-pot chemocatalytic conversion of xylose to value-added C_(5)/C_(4) cyclic ethers over a novel ZrO_(2)-doped Ni-Pd catalyst supported on H-βzeolite was demonstrated.Optimized catalyst,namely,Ni_(2) Pd_(0.5)Zr_(1)/H-β(25),achieved a high xylose transformation(>99%)with high selectivities toward 2-methyltetrahydrofuran(48.6%)and tetrahydropyran(20.2%)under mild reaction conditions(200℃,1.0 MPa H_(2),and 2 h).Systematic investigation of the physicochemical properties of the catalyst revealed that ZrO_(2) doping induced O vacancies,enhanced H_(2) activation,and improved metal dispersion,thereby promoting hydrogenation and hydrodeoxygenation.In situ diffuse reflectance infrared Fourier transform spectroscopy using furfural and furfuryl alcohol probes confirmed preferential adsorption geometries and electronic interactions at metal-ZrO_(2) interfaces.Time-resolved and feedstock variation studies further elucidated the reaction mechanism and highlighted the roles of key intermediates.The proposed catalyst exhibited excellent recyclability with only a minor decline in performance after multiple xylose conversion cycles.This study provides mechanistic insights and design principles for the development of efficient multifunctional catalysts for biomass valorization.
基金Supported by Shanghai Agriculture Applied Technology Development Program (Grant No.T20220120).
文摘[Objectives]This study was conducted to establish a quantitative assessment method for the textural quality of chieh-qua fruit.[Methods]Using two modes of a texture analyzer,namely TPA(texture profile analysis)and puncture,the index data of the fruit were obtained by setting different trigger forces,deformation levels,test speeds,as well as puncture speeds and puncture depths.The data included TPA hardness,adhesiveness,springiness,cohesiveness,gumminess,chewiness,resilience,as well as skin hardness,skin toughness,flesh hardness,fracturability,and compactness.[Results]Different deformation levels had a significant impact on all parameters.Hardness,adhesiveness,gumminess and chewiness showed a trend of first increasing and then decreasing with the deformation level increasing.When the deformation level was 30%,the adhesiveness,gumminess and chewiness reached their maximum values.When the deformation level was 50%,TPA hardness reached its maximum.When the compression speed was 3 mm/s,the measured values of TPA hardness,adhesiveness,chewiness,and resilience were at their maximums.The skin hardness varied significantly under different trigger forces.When the trigger force was 15 g,the skin hardness reached a maximum value of 944.63 g,and the skin toughness,flesh hardness,fracturability,and compactness also reach their maximum values respectively.When the puncture depth was 12 mm,the flesh hardness and skin toughness reached their maximums of 682.51 g and 1.82 mm,respectively.In the TPA mode,the flesh hardness of chieh-qua showed an extremely significant negative correlation with springiness,cohesiveness,and resilience(P<0.01).The fruit fracturability detected by puncture had an extremely significant positive correlation with compactness(P<0.01).[Conclusions]The evaluation method for measuring chieh-qua texture by combining TPA and the puncture mode could accurately and quantitatively reflect the differences in the flesh texture quality of chieh-qua.The optimal parameters for texture measurement of chieh-qua fruit were determined as a 15 g trigger force with 50%deformation and a 3 mm/s compression speed in TPA mode,and a 15 g trigger force with a 12 mm puncture depth in puncture mode.Puncture speed was found to have no significant effect on the texture indices of chieh-qua.
基金Project supported by the National Natural Science Foundation of China(Nos.52405095,12272089,and 92360305)the Guangdong Basic and Applied Basic Research Foundation of China(No.2023A1515110557)+4 种基金the Natural Science Foundation of Liaoning Province of China(No.2023-BSBA-102)the Open Fund of National Key Laboratory of Particle Transport and Separation Technology of China(No.WZKF-2024-6)the Open Project of Guangxi Key Laboratory of Automobile Components and Vehicle Technology of China(Nos.2024GKLACVTKF07 and 2024GKLACVTKF06)the Basic Research Projects of Liaoning Provincial Department of Education of China(No.JYTQN2023162)the Fundamental Research Funds for the Central Universities of China(No.N2403022)。
文摘The testing of large structures is limited by high costs and long cycles, making scaling methods an attractive solution. However, the scaling process of elastic rings introduces complexities in multi-parameter geometric distortions, leading to a diminution in the predictive accuracy of the distorted similitude. To address this challenge, this study formulates a novel set of scaling laws, tailored to account for the intricate geometric distortions associated with elastic rings. The proposed scaling laws are formulated based on the intrinsic deformation characteristics of elastic rings, rather than the traditional systemic governing equations. Numerical and experimental cases are conducted to assess the efficacy and precision of the proposed scaling laws, and the obtained results are compared with those achieved by traditional methods. The outcomes demonstrate that the scaling laws put forth by this study significantly enhance the predictive capabilities for deformations of elastic rings.
基金supported in part by the Mining Hydraulic Technology and Equipment Engineering Research Center,Liaoning Technical University,Fuxin,China(Grant No.MHTE23-R04)the Fundamental Research Funds for the Central Universities(ID N25BSS068).
文摘This study presents an implicit multiphysics coupling method integrating Computational Fluid Dynamics(CFD),the Multiphase Particle-in-Cell(MPPIC)model,and the Finite Element Method(FEM),implemented with OpenFOAM,CalculiX,and preCICE to simulate fluid-particle-structure interactions with large deformations.Mesh motion in the fluid field is handled using the radial basis function(RBF)method.The particle phase is modeled by MPPIC,where fluid-particle interaction is described through momentum exchange,and inter-particle collisions are characterized by collision stress.The structural field is solved by nonlinear FEM to capture large deformations induced by geometric nonlinearity.Coupling among fields is realized through a partitioned,parallel,and non-intrusive iterative strategy,ensuring stable transfer and convergence of interface forces and displacements.Notably,the influence of particles on the structure is not direct but mediated by the fluid,while structural motion directly affects particle dynamics.The results demonstrate that the proposed approach effectively captures multiphysics interaction processes and provides a valuable reference for numerical modeling of coupled fluid-particle-structure systems.
基金support provided by the National Natural Science Foundation of China(No.22273043).
文摘As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency of exciton utilization and the overall performance of organic light-emit-ting devices are closely linked to the singlet-triplet energy gap(ΔE_(ST))of MR-TADF emitters.Identifying an economic and accu-rate theoretical approach to predictΔE_(ST)would be beneficial for high-throughput screening and facilitate the inverse design of MR-TADF molecules.In this study,we evaluated the S_(1)state energy(E(S_(1))),T_(1)state ener-gy(E(T_(1))),andΔE_(ST)using three different physical interpretations:adiabatic excitation ener-gy,vertical absorption energy,and vertical emission energy.We employed the time-depen-dent density functional theory(TDDFT)and delta self-consistent field(ΔSCF)methods to calculate E(S_(1)),E(T_(1)),andΔE_(ST)for 20 MR-TADF molecules reported in the literature.We compared these calculated values with experimental data obtained from fluorescence spec-troscopy at room-temperature(or 77 K)and phosphorescence spectroscopy conducted at 77 K.Our findings indicate that the vertical absorption energy at the S0 state minimum,deter-mined by theΔSCF method,accurately predicts the S_(1)state energy.Similarly,the vertical absorption energy at the S0 state minimum,calculated using the TDDFT method,effectively predicts the T_(1)state energy.TheΔE_(ST)derived from the difference between these two excita-tion energies exhibited the smallest mean absolute error of only 0.039 eV compared to the ex-perimental values.This combination represents the most accurate and cost-effective method reported to date for predicting theΔE_(ST)of MR-TADF molecules,and can be integrated into AI-driven inverse design workflows for new emitters.
基金supported by the Science and Technology Project of State Grid Corporation of China(5400-202199281A-0-0-00).
文摘In a multiple voltage source converter(VSC)system,the nonlinear characteristics of phase-locked loops(PLLs)and their interactions have a significant influence on the synchronization stability of converters.In this paper,these influences are investigated from the perspective of the time domain.First,a novel time-domain model of the multi-VSC system is obtained by using a multi-scale method.On this basis,a stability criterion is proposed to assess the synchronization stability of the system.Then,the accuracy of the time-domain model and its stability criterion in various conditions are discussed.Moreover,the negative impact of the interaction on the system is quantified.Finally,the above theoretical analysis is also verified in the controller hardware-in-the-loop(CHIL)experiments.
基金supported by the Fuxing Nursing Research Foundation of Fudan University[FNF202352].
文摘Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of informing the optimization of disclosure processes and meeting the communication needs of affected families.Methods In accordance with the Joanna Briggs Institute(JBI)methodology for mixed methods systematic reviews,the convergent segregated approach was used in this review.Articles were retrieved from 11 databases,including PubMed,Web of Science,CINAHL,CENTRAL,Embase,Ovid/Medline,PsycINFO,PsycArticles,Scopus,ERIC,and China National Knowledge Infrastructure(CNKI).The quality of the selected articles was assessed using the Mixed Method Appraisal Tool(MMAT).The review protocol was registered on PROSPERO(CRD42024542746).Results A total of 21 studies from 10 countries were included.Their methodological quality was generally medium to high,with MMAT scores ranging from 60%to 100%.The synthesis yielded three core themes:1)the spectrum of professional and societal attitudes toward disclosure;2)the dynamic practices of navigating disclosure amid uncertainty,including timing and environment,stakeholders,and content of disclosure;and 3)factors influencing disclosure,including children’s,parental,healthcare professionals’,and socio-cultural factors.Conclusions This review synthesized the perspectives and experiences of healthcare professionals regarding disclosure in childhood cancer,highlighting the complexity and multidimensional nature of this process in clinical practice.Future research should further investigate the experiences and needs of children and their parents,explore cultural variations in disclosure practices,develop context-appropriate assessment tools,and construct multidimensional intervention strategies to enhance the humanistic care and professional effectiveness of the disclosure process.
