In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar perce...In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes.展开更多
In this study,FeCr_(x)MnAlCu(x=0,0.5,1.0,1.5,2.0)high-entropy alloys were fabricated using vacuum arc melting,and the corrosion behavior of these alloys in 3.5wt%NaCl solution at room temperature was investigated by e...In this study,FeCr_(x)MnAlCu(x=0,0.5,1.0,1.5,2.0)high-entropy alloys were fabricated using vacuum arc melting,and the corrosion behavior of these alloys in 3.5wt%NaCl solution at room temperature was investigated by electrochemical dynamic potential polarization curves and immersion experiments.The microstructure results show that the high-entropy alloy with x=0 has a body-centered cubic phase structure,whereas the high-entropy alloys with x=0.5–2.0 have a mixed face-centered cubic+body-centered cubic dual-phase structure.The corrosion results show that the corrosion resistance of the high-entropy alloy is increased with the increase in Cr content.Among them,the high-entropy alloy with x=2.0 exhibits the optimal corrosion resistance:the highest self-corrosion potential(E_(corr)=−0.354 V vs.Ag/AgCl),the smallest self-corrosion current density(I_(corr)=1.991×10^(−6)A·cm^(−2)),and the smallest corrosion rate(0.0292 mm/a).The composite passivation film of oxides and hydroxides is formed on the surface of the corroded high-entropy alloys,and the Cr_(2)O_(3)content is increased with the increase in Cr content,which effectively improves the stability and protective properties of the passivation film.展开更多
To investigate the effect of solution treatment and aging process parameters on the microstructure and mechanical properties of TB18 titanium alloy,process optimization research was conducted based on the mixed-level ...To investigate the effect of solution treatment and aging process parameters on the microstructure and mechanical properties of TB18 titanium alloy,process optimization research was conducted based on the mixed-level orthogonal experiment design of factor levels.Results show that through range analysis,the significance order of process parameters is determined as follows:solution cooling method>solution temperature>aging time>aging temperature>solution time.Considering the strength-ductility matching and engineering application requirements,the benchmark parameters are selected as solution time of 1 h,solution cooling method of air cooling(AC),aging temperature of 525℃,and aging time of 4 h.Furthermore,the effects of solution temperature in the range of 790–870℃ on the impact toughness and micro-fracture characteristics of the alloy were studied.The results reveal that the larger the area of shear lip and fibrous zone,and the smaller the area of radiation zone,the better the toughness of the alloy.With the increase in solution temperature,the length of secondary cracks on the fracture surface increases,the number of dimples increases,and the toughness is enhanced.Based on the collaborative optimization of strength and toughness,the optimal heat treatment process for TB18 alloy is determined as 870℃/1 h,AC+525℃/4 h,AC.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
Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM,increasing the active material content in the electrode by utilizing high-conductivity c...Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM,increasing the active material content in the electrode by utilizing high-conductivity carbon nanotubes(CNT)conductive materials,and electrode thickening.However,these methods are still limited due to the limitation in the capacity of high-nickel NCM,aggregation of CNT conductive materials,and nonuniform material distribution of thick-film electrodes,which ultimately damage the mechanical and electrical integrity of the electrode,leading to a decrease in electrochemical performance.Here,we present an integrated binder-CNT composite dispersion solution to realize a high-solids-content(>77 wt%)slurry for high-mass-loading electrodes and to mitigate the migration of binder and conductive additives.Indeed,the approach reduces solvent usage by approximately 30%and ensures uniform conductive additive-binder domain distribution during electrode manufacturing,resulting in improved coating quality and adhesive strength for high-mass-loading electrodes(>12 mAh cm^(−2)).In terms of various electrode properties,the presented electrode showed low resistance and excellent electrochemical properties despite the low CNT contents of 0.6 wt%compared to the pristine-applied electrode with 0.85 wt%CNT contents.Moreover,our strategy enables faster drying,which increases the coating speed,thereby offering potential energy savings and supporting carbon neutrality in wet-based electrode manufacturing processes.展开更多
We investigated the phase behavior of diblock copolymer AB/homopolymer C blends in concentrated aqueous solutions using a simulated annealing method.Phase diagrams were constructed as a function of the concentration o...We investigated the phase behavior of diblock copolymer AB/homopolymer C blends in concentrated aqueous solutions using a simulated annealing method.Phase diagrams were constructed as a function of the concentration of all polymers(Φ)and the volume fraction of homopolymer(fC).Rich phase transition sequences were observed,especially reentrant phase transitions,such as lamellae→inverted cylinders→gyroids→lamellae→disorder,for a givenΦwith increasing fC.By analyzing the variations in the average contact numbers between different components and the effective volume fractions of B-domains,we elucidated the mechanisms of the reentrant phase transitions.We found that the strong attraction between B and C leads to the swelling of B-domains upon addition of homopolymer.Concurrently,the solvent preferentially swells the A-domains over the B+C-domains.The competing swelling effects of the solvent and homopolymer on the A-domains and B-domains,respectively,triggered the reentrant phase behavior in the symmetric AB copolymer system upon addition of homopolymer.展开更多
ZnO thin-film transistors(TFTs)with channel layers fabricated by spin-coating are demonstrated.A nano ZnO colloidal aqueous solution with zinc nitrate dissolved in it was first deposited on the ATO/ITO/glass substrate...ZnO thin-film transistors(TFTs)with channel layers fabricated by spin-coating are demonstrated.A nano ZnO colloidal aqueous solution with zinc nitrate dissolved in it was first deposited on the ATO/ITO/glass substrate by spin-coating process.The thin-film transistor with well-controlled and densely packed ZnO crystalline layer was obtained by thermal annealing the system of colloidal solution film coated ATO/ITO/glass substrate.By optimizing the fabrication conditions,the fabricated thin-film transistors exhibited superior field-effect properties,which were stable,highly transparent,n-channel and enhancement-mode with a channel mobility as large as 3.02 cm^(2)·V^(-1).s^(-1).Our method of fabricating ZnO thin-film transistors was simple,high efficiency,and feasible for the batch production with low cost.展开更多
The existence of a global attractor is established for generalized Navier-Stokes equations incorporating damping term within the periodic domainΩ=[−π,π]^(n).Initially,we show the existence and uniqueness of strong ...The existence of a global attractor is established for generalized Navier-Stokes equations incorporating damping term within the periodic domainΩ=[−π,π]^(n).Initially,we show the existence and uniqueness of strong solutions.Subsequently,we verify the continuity of the associated semigroup when max{2n+1/n-1,5n+2/3n-2} < β <3n+2/n-2.Finally,we establish the existence of both H^(α)-global attractor and H^(2α)-global attractor.展开更多
TMPRSS2 plays a crucial role in facilitating the entry of both the influenza virus and the SARSCoV-2 coronavirus into host cells.Recent studies have identified a guanine-rich sequence in the proximal promoter region o...TMPRSS2 plays a crucial role in facilitating the entry of both the influenza virus and the SARSCoV-2 coronavirus into host cells.Recent studies have identified a guanine-rich sequence in the proximal promoter region of the TMPRSS2 gene,which can form G-quadruplex structures(TMPRSS2-G4s)that are potential targets for small molecules to inhibit TMPRSS2 expression.However,the structural details of the major TMPRSS2-G4 and its complex with small molecules remain unknown,hindering the development of antiviral drugs targeting TMPRSS2-Gquadruplexes(G4s).This study reports the first high-resolution nuclear magnetic resonance(NMR)solution structure of the major TMPRSS2-G4,which consists of a three-tetrad core parallel-stranded G4.Both 3′and 5′flanking regions form well-defined capping structures stabilized by multiple hydrogen bonds.Importantly,we found that berberine,an antiviral alkaloid,strongly binds to the major TMPRSS2-G4 and determined its binding complex structure with TMPRSS2-G4 at a 2∶1 binding stoichiometry.Each berberine molecule recruits an adjacent flanking residue,forming a coplanar structure superimposed on two outer G-tetrads.Moreover,we demonstrated that the major TMPRSS2-G4 can stably form within a longer deoxyribonucleic acid(DNA)context and be targeted by small molecules to inhibit DNA polymerase activity.Overall,this study provides structural insights into the recognition mechanism of small molecules by the major TMPRSS2-G4 and may facilitate the development of novel antiviral therapeutics targeting TMPRSS2-G4.展开更多
Hydrochloric acid(HCl)extensively exists in deep underground projects,arising from the transportation of industrial raw materials or fracturing fluids of petroleum engineering.It results in corrosion,which can signifi...Hydrochloric acid(HCl)extensively exists in deep underground projects,arising from the transportation of industrial raw materials or fracturing fluids of petroleum engineering.It results in corrosion,which can significantly impact the stability of surrounding rock structures.Therefore,in-depth analysis of the degradation of rock corroded by the HCl solution is an essential task for underground engineering.In this study,the granite specimens are initially treated with the HCl solution with various concentrations.Then,the tests and analyses,such as electrical conductivity(EC)measurements,mineral composition assays,and Brazilian splitting tests,are employed to investigate the corrosion mechanism of the HCl solution.Our results and findings are generally as follows:(1)As the immersion time increases,the EC exhibits a relatively high level at pH value of 1,a decreasing trend at pH value of 3,and an increasing trend at pH value of 5 and 7.(2)The HCl solutions with various concentration have different effect on mineral composition,characterized by an increase in proportion of SiO_(2) and a reduction in proportion of Na_(2)O,Al_(2)O_(3),K_(2)O,MgO,and CaO,as the solution pH value decreases.(3)After immersion in the solutions with pH values of 1,3,and 5,the tensile strength of the granite decreases by 23.85%,20.84%,and 20.24%;the average stiffness of the specimen decreases by 29.29%,23.43%,and 11.97%;the proportion of releasable energy increases by 6%,4%,and -2%;the releasable energy decreases by 54.96%,26.09%,and 14.52%;and the dissipated energy decreases by approximately 68.85%,41.39%,and 5.41%,respectively.(4)The evolution of physical and mechanical properties of the immersed granite specimen can be analyzed from a chemical aspect.The corrosive action of HCl cleaves Si–O and Al–O chemical bonds within the granite,particularly altering the tetrahedral structures of its silicate components.This process involves breaking existing chemical bonds and the formation of new ones,ultimately destroying the silicate molecular structures.As the concentration of HCl increases,the rate of these reactions accelerates,progressively weakening the chemical bonds and consequently deteriorating the mechanical characteristics of the granite.These findings can deepen our knowledge about the corrosion effect of HCI solutions on natural surrounding rocks and serve as references for further research on rock corrosion mechanisms in underground engineering.展开更多
Quick and accurate determination of the optimal synchrophase angle is crucial for synchrophasing control of multi-propeller aircraft with low noise.This paper proposes a novel noise prediction and optimization strateg...Quick and accurate determination of the optimal synchrophase angle is crucial for synchrophasing control of multi-propeller aircraft with low noise.This paper proposes a novel noise prediction and optimization strategy,developing a continuous and accurate noise prediction model and obtaining its minimum by solving the Hessian matrix and Fourier-Frobenius matrix.Firstly,a novel propeller noise prediction method uses acoustic simulation pressure signals and improved propeller signatures theory to accurately estimate noise for all synchrophase angles and receiving points.Secondly,a novel optimization approach is proposed to solve the analytical solution of the minimum propeller noise:(A)A noise objective function is established,and use its first derivatives’zeros and Hessian matrix to determine the function minimum.(B)A novel Euler formula transform method is proposed to convert trigonometric polynomials into algebraic polynomials,changing the zeros of the former into those of the latter.(C)Utilize the Fourier-Frobenius matrix method to solve the zeros of algebraic polynomials.To assess the computation time and accuracy,a turboprop aircraft with two six-bladed propellers was analyzed using the computational fluid dynamics and acoustic analogy method,providing acoustic pressure signals at 20 receivers for noise prediction and optimization.The Durand-Kerner and Fourier-Frobenius matrix methods were compared.Results demonstrate that improved propeller signatures theory is more accurate,and the Hessian matrix+Fourier-Frobenius matrix method is faster and more precise than the Hessian matrix+Durand-Kerner method.展开更多
Anammox bacteria in constructed wetlands(CWs)play pivotal role in sustainable nitrogen transformation,yet existing studies lack comprehensive analysis of environmental gradients and microbial interactions,both key fac...Anammox bacteria in constructed wetlands(CWs)play pivotal role in sustainable nitrogen transformation,yet existing studies lack comprehensive analysis of environmental gradients and microbial interactions,both key factors in anammox bacteria enrichment.This study investigated the mechanisms driving anammox bacteria enrichment in lab-scale simulated CWs treating high-nitrogen wastewater,focusing on bacterial community re-sponses across wetland layers with various strategies,including continuous up-flow influent,nitrogen loading increase,effluent recirculation,intermittent influent,and anammox bacteria inoculation.Results showed that total relative and absolute abundances of anammox bacteria ranged from 0.77%to 12.50%and from 0.13 to 6.46×10^(7) copies/g,respectively.Dissolved oxygen and pH had significant positive correlations with the absolute abundance of anammox bacteria,while organic matter and nitrate negatively impacted their relative abundance.Permutational multivariate analysis of variance indicated that spatial heterogeneity explained more variation in anammox bacteria abundance(43.44%)compared to operational strategies(8.58%).In terms of microbial interactions,60 dominant species exhibited potential correlations with anammox bacteria,comprising 170 interactions(105 positive and 65 negative),which suggested that anammox bacteria generally foster cooperative relationships with dominant bacteria.Notably,significant interspecies interactions were observed between Candidatus Kuenenia(dominant anammox bacteria in CWs)and species within the genera Chitinivibrio-nia and Anaerolineaceae,suggesting that microbial interactions primarily manifest as indirect facilitative effects rather than direct mutualistic relationships.Given that the Normalized Stochasticity Ratio in CWs were<50%,this study inferred that environmental gradients have greater influence on anammox bacteria than microbial interactions.展开更多
In this paper,we consider a robust semi-infinite interval-valued optimization problem with inequality constraints having an uncertain parameter.The parametric representation of the aforesaid problem is also considered...In this paper,we consider a robust semi-infinite interval-valued optimization problem with inequality constraints having an uncertain parameter.The parametric representation of the aforesaid problem is also considered in order to derive the necessary and sufficient optimality conditions.Furthermore,we formulate a mixed-type dual problem and derive duality results which associate the robust weak efficient solution of the primal and its dual problems.Several examples are given to illustrate the results in the manuscript.展开更多
Zn-Mn alloys are regarded as promising biodegradable metals for orthopedic applications owing to their moderate degradation rates and favorable osteogenic properties.However,the presence of a substantial number of sec...Zn-Mn alloys are regarded as promising biodegradable metals for orthopedic applications owing to their moderate degradation rates and favorable osteogenic properties.However,the presence of a substantial number of second-phase particles in Zn-based alloys might induce severe localized degradation via micro-coupling corrosion,thereby compromising the mechanical integrity of the alloy during in vivo tissue regeneration.In this study,high pressure solid solution(HPSS)treatment was conducted at 5 GPa and 380℃ for 1 h to fabricate Zn-0.5 Mn alloys.Microstructural characterization revealed that the HPSS treatment facilitated the formation of a supersaturated solid solution by completely dissolving theζ-MnZn_(13) phase into theα-Zn matrix.The resultant strengthening mechanisms,including supersaturated solid solution strengthening,grain-size strengthening,and dislocation strengthening,collectively enhanced the compressive yield strength(σ_(cys))of the Zn-0.5 Mn alloy to about 183.7 MPa,approximately three times that of the as-cast(AC)Zn-0.5 Mn alloy.Moreover,compared with the AC alloy,the HPSS Zn-0.5 Mn alloy exhibited uniform degradation behavior with a markedly reduced degradation rate.展开更多
In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→...In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions.展开更多
The scalable fabrication of stretchable conjugated polymer films via solution printing is essential for their practical application in largearea wearable electronics.However,the printed conjugated polymer films typica...The scalable fabrication of stretchable conjugated polymer films via solution printing is essential for their practical application in largearea wearable electronics.However,the printed conjugated polymer films typically exhibit high crystallinity,limiting their mechanical deformability.Herein,we propose a plasticizer-assisted printing strategy to simultaneously enhance the stretchability and electrical performance of films based on the conjugated polymer poly(3-(5-(5-methylselenophen-2-yl)thiophen-2-yl)-6-(5-methylthiophen-2-yl)-2,5-bis(4-octyltetradecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione)(P(TDPP-Se)).The incorporation of a plasticizer trioctyl trimellitate(TOTM)promotes P(TDPP-Se)aggregation in initial solution,facilitates chain alignment under flow field,and shorten solidification process,thereby restricting randomly polymer crystallization.Consequently,a low-crystallinity film with favorable edge-on orientation,strong chain alignment and improved chain dynamics is realized,which effectively alleviates crystallites fragmentation and crack propagation under large strain.The TOTM-plasticized film exhibits approximately 2-fold improvements in fracture strain and charge mobility,along with superior mobility retention under 100%strain in comparison to the neat film.This study provides a feasible approach for microstructure control in printed stretchable conjugated polymer film.展开更多
Circumlunar abort trajectories constitute a vital contingency return strategy during the translunar phase of crewed lunar missions.This paper proposes a methodology for constructing the solution set of the circumlunar...Circumlunar abort trajectories constitute a vital contingency return strategy during the translunar phase of crewed lunar missions.This paper proposes a methodology for constructing the solution set of the circumlunar abort trajectory and leverages its advantageous properties to address the optimization design problem of abort trajectories.Initially,a solution set of all feasible abort trajectories,originating from an abort point on the nominal trajectory and complying with fundamental reentry constraints,is formulated through the introduction of two novel design parameters.Subsequently,the geometric characteristics of the solution set,as well as the distributional properties of key iterative constraint responses,including flight time and velocity increment,are analyzed.Finally,the characteristics exhibited in the solution set are employed to directly identify the design parameters of the abort trajectories with minimum flight time and velocity increment,thereby providing solutions to two distinct types of optimization problems.The simulation results for a variety of nominal trajectories,encompassing the reconstruction and redesign of the Apollo13 abort trajectory,validate the proposed method,demonstrating its ability to directly generate optimal abort trajectories.The method proposed in this paper investigates feasible abort trajectories from a global perspective,providing both a framework and convenience for mission planning and iterative optimization in abort trajectory design.展开更多
The use of Al-V alloys as intermediate additives is pivotal for producing high-performance Ti alloys.Traditionally,the synthesis of these alloys relies on high-purity V_(2)O_(5),with sodium metavanadate as an essentia...The use of Al-V alloys as intermediate additives is pivotal for producing high-performance Ti alloys.Traditionally,the synthesis of these alloys relies on high-purity V_(2)O_(5),with sodium metavanadate as an essential intermediate in V_(2)O_(5)production.This study explores an alternative approach utilizing sodium metavanadate directly,offering an aluminothermic process to alleviate the environmental impact and reduce the time required for V_(2)O_(5)preparation.Al-V alloys are synthesized using sodium metavanadate derived from a shale V-rich solution,and the impurity-migration behaviors are comprehensively analyzed,specifically focusing on Fe,Al,and Na.The result sreveal that Al interacts with CaO to form a slag phase that is different from the alloy,whereas Na undergoes a sequence of reductions (NaVO_(3)→Na_(2)V_(2)O_(5)→NaVO_(2)→Na)and volatilizes at 25-1200℃,thereby avoiding incorporation into the alloy.Fe,reduced by Al,enriches the alloy phase and induces a phase transition(Al-V→Al-Fe→Fe-V)in the presence of excess Fe.Sodium metavanadate(Fe≤0.05wt%)derived from the shale V-rich solution enables the production of a uniform AlV65 alloy with 66.56wt%V,33.14wt%Al,0.08wt%Fe,0.07wt%C,0.02wt%N,and 0.12wt%O.These results establish a streamlined,efficient framework for the future preparation of Al-V alloys from shale V-rich solutions.展开更多
Acid is commonly used to separate phosphorus-containing solid solutions from steelmaking slag.However,the acid leaching solution obtained from this process cannot be directly utilized and thus requires purification.Th...Acid is commonly used to separate phosphorus-containing solid solutions from steelmaking slag.However,the acid leaching solution obtained from this process cannot be directly utilized and thus requires purification.The effect of different conditions on the calcium and iron removal characteristics of modified steelmaking slag leaching solution was investigated.Additionally,the removal mechanism was analyzed by thermodynamic calculations.The results indicated that the addition of soybean straw ash in steelmaking slag modification enabled K_(2)O to enter the phosphorus-containing solid solution,promoting phosphorus enrichment.Valuable elements such as phosphorus and potassium were more easily dissolved in the mixed acid.The oxalic acid concentration had a significant effect on the calcium removal rate,whereas the effects of temperature,stirring rate,and time on the calcium removal rate were minor.The main component of the calcium removal precipitate was CaC_(2)O_(4)·H_(2)O,with a removal rate up to 94.48%.During the iron removal process,when the pH value of the solution was low,Fe^(3+)mainly reacted to form the iron hydroxide precipitate for removal.Increasing the pH value of the solution would cause Fe^(3+)to combine with H_(2)PO_(4)^(-),forming FePO_(4)·2H_(2)O precipitate,leading to a reduction in the phosphorus content of the leaching solution.展开更多
The detection of amino acid enantiomers holds significant importance in biomedical,chemical,food,and other fields.Traditional chiral recognition methods using fluorescent probes primarily rely on fluorescence intensit...The detection of amino acid enantiomers holds significant importance in biomedical,chemical,food,and other fields.Traditional chiral recognition methods using fluorescent probes primarily rely on fluorescence intensity changes,which can compromise accuracy and repeatability.In this study,we report a novel fluorescent probe(R)-Z1 that achieves effective enantioselective recognition of chiral amino acids in water by altering emission wavelengths(>60 nm).This water-soluble probe(R)-Z1 exhibits cyan or yellow-green luminescence upon interaction with amino acid enantiomers,enabling reliable chiral detection of 14 natural amino acids.It also allows for the determination of enantiomeric excess through monitoring changes in luminescent color.Additionally,a logic operation with two inputs and three outputs was constructed based on these optical properties.Notably,amino acid enantiomers were successfully detected via dual-channel analysis at both the food and cellular levels.This study provides a new dynamic luminescence-based tool for the accurate sensing and detection of amino acid enantiomers.展开更多
基金Supported by the Doctoral Research Start-up Project of Yuncheng University(YQ-2023067)Project of Shanxi Natural Science Foundation(202303021211189)+1 种基金Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Provinces(20220036)Shanxi ProvinceIntelligent Optoelectronic Sensing Application Technology Innovation Center and Shanxi Province Optoelectronic Information Science and TechnologyLaboratory,Yuncheng University.
文摘In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes.
基金Gansu Provincial Science and Technology Major Special Program(24ZDWA008)Fourth Batch of Top Leading Talents Fund Projects in Gansu Province(ZZ2023G50100013)。
文摘In this study,FeCr_(x)MnAlCu(x=0,0.5,1.0,1.5,2.0)high-entropy alloys were fabricated using vacuum arc melting,and the corrosion behavior of these alloys in 3.5wt%NaCl solution at room temperature was investigated by electrochemical dynamic potential polarization curves and immersion experiments.The microstructure results show that the high-entropy alloy with x=0 has a body-centered cubic phase structure,whereas the high-entropy alloys with x=0.5–2.0 have a mixed face-centered cubic+body-centered cubic dual-phase structure.The corrosion results show that the corrosion resistance of the high-entropy alloy is increased with the increase in Cr content.Among them,the high-entropy alloy with x=2.0 exhibits the optimal corrosion resistance:the highest self-corrosion potential(E_(corr)=−0.354 V vs.Ag/AgCl),the smallest self-corrosion current density(I_(corr)=1.991×10^(−6)A·cm^(−2)),and the smallest corrosion rate(0.0292 mm/a).The composite passivation film of oxides and hydroxides is formed on the surface of the corroded high-entropy alloys,and the Cr_(2)O_(3)content is increased with the increase in Cr content,which effectively improves the stability and protective properties of the passivation film.
基金Key Program of National Natural Science Foundation of China(52431001)。
文摘To investigate the effect of solution treatment and aging process parameters on the microstructure and mechanical properties of TB18 titanium alloy,process optimization research was conducted based on the mixed-level orthogonal experiment design of factor levels.Results show that through range analysis,the significance order of process parameters is determined as follows:solution cooling method>solution temperature>aging time>aging temperature>solution time.Considering the strength-ductility matching and engineering application requirements,the benchmark parameters are selected as solution time of 1 h,solution cooling method of air cooling(AC),aging temperature of 525℃,and aging time of 4 h.Furthermore,the effects of solution temperature in the range of 790–870℃ on the impact toughness and micro-fracture characteristics of the alloy were studied.The results reveal that the larger the area of shear lip and fibrous zone,and the smaller the area of radiation zone,the better the toughness of the alloy.With the increase in solution temperature,the length of secondary cracks on the fracture surface increases,the number of dimples increases,and the toughness is enhanced.Based on the collaborative optimization of strength and toughness,the optimal heat treatment process for TB18 alloy is determined as 870℃/1 h,AC+525℃/4 h,AC.
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supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2022M3H4A6A0103720142)the National Research Council of Science&Technology(NST)grant by the Korea government(MSIT)(No.GTL24011-000)+1 种基金the Technology Innovation Program(RS-2024-00404165)through the Korea Planning&Evaluation Institute of Industrial Technology(KEIT)funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea)supported by the Samsung SDI Co.Ltd.and the Korea Institute of Science and Technology(KIST)institutional program(2E33942,2E3394B)。
文摘Strategies for achieving high-energy-density lithium-ion batteries include using high-capacity materials such as high-nickel NCM,increasing the active material content in the electrode by utilizing high-conductivity carbon nanotubes(CNT)conductive materials,and electrode thickening.However,these methods are still limited due to the limitation in the capacity of high-nickel NCM,aggregation of CNT conductive materials,and nonuniform material distribution of thick-film electrodes,which ultimately damage the mechanical and electrical integrity of the electrode,leading to a decrease in electrochemical performance.Here,we present an integrated binder-CNT composite dispersion solution to realize a high-solids-content(>77 wt%)slurry for high-mass-loading electrodes and to mitigate the migration of binder and conductive additives.Indeed,the approach reduces solvent usage by approximately 30%and ensures uniform conductive additive-binder domain distribution during electrode manufacturing,resulting in improved coating quality and adhesive strength for high-mass-loading electrodes(>12 mAh cm^(−2)).In terms of various electrode properties,the presented electrode showed low resistance and excellent electrochemical properties despite the low CNT contents of 0.6 wt%compared to the pristine-applied electrode with 0.85 wt%CNT contents.Moreover,our strategy enables faster drying,which increases the coating speed,thereby offering potential energy savings and supporting carbon neutrality in wet-based electrode manufacturing processes.
基金financially supported by the Natural Science Foundation of Shandong Province(Nos.ZR2023QA136,ZR2021MA073 and ZR2024QA235)the National Natural Science Foundation of China(No.22173051).
文摘We investigated the phase behavior of diblock copolymer AB/homopolymer C blends in concentrated aqueous solutions using a simulated annealing method.Phase diagrams were constructed as a function of the concentration of all polymers(Φ)and the volume fraction of homopolymer(fC).Rich phase transition sequences were observed,especially reentrant phase transitions,such as lamellae→inverted cylinders→gyroids→lamellae→disorder,for a givenΦwith increasing fC.By analyzing the variations in the average contact numbers between different components and the effective volume fractions of B-domains,we elucidated the mechanisms of the reentrant phase transitions.We found that the strong attraction between B and C leads to the swelling of B-domains upon addition of homopolymer.Concurrently,the solvent preferentially swells the A-domains over the B+C-domains.The competing swelling effects of the solvent and homopolymer on the A-domains and B-domains,respectively,triggered the reentrant phase behavior in the symmetric AB copolymer system upon addition of homopolymer.
文摘ZnO thin-film transistors(TFTs)with channel layers fabricated by spin-coating are demonstrated.A nano ZnO colloidal aqueous solution with zinc nitrate dissolved in it was first deposited on the ATO/ITO/glass substrate by spin-coating process.The thin-film transistor with well-controlled and densely packed ZnO crystalline layer was obtained by thermal annealing the system of colloidal solution film coated ATO/ITO/glass substrate.By optimizing the fabrication conditions,the fabricated thin-film transistors exhibited superior field-effect properties,which were stable,highly transparent,n-channel and enhancement-mode with a channel mobility as large as 3.02 cm^(2)·V^(-1).s^(-1).Our method of fabricating ZnO thin-film transistors was simple,high efficiency,and feasible for the batch production with low cost.
文摘The existence of a global attractor is established for generalized Navier-Stokes equations incorporating damping term within the periodic domainΩ=[−π,π]^(n).Initially,we show the existence and uniqueness of strong solutions.Subsequently,we verify the continuity of the associated semigroup when max{2n+1/n-1,5n+2/3n-2} < β <3n+2/n-2.Finally,we establish the existence of both H^(α)-global attractor and H^(2α)-global attractor.
基金supported by the National Natural Science Foundation of China (Nos.82322065,82173707,and 82204241)the Innovation and Entrepreneurship (Shuangchuang) Program of Jiang-su Province (2024)+3 种基金the Natural Science Foundation of Jiangsu Province (No.BK20221039)the Project Program of State Key Laboratory of Natural Medicines (China Pharmaceutical University,No.SKLNMZZ2024JS12)the Fundamental Research Funds for the Central Universities (No.2632025ZD06)the Scientific Research Foundation for High-level Faculty,China Pharmaceutical University (No.3150020065)
文摘TMPRSS2 plays a crucial role in facilitating the entry of both the influenza virus and the SARSCoV-2 coronavirus into host cells.Recent studies have identified a guanine-rich sequence in the proximal promoter region of the TMPRSS2 gene,which can form G-quadruplex structures(TMPRSS2-G4s)that are potential targets for small molecules to inhibit TMPRSS2 expression.However,the structural details of the major TMPRSS2-G4 and its complex with small molecules remain unknown,hindering the development of antiviral drugs targeting TMPRSS2-Gquadruplexes(G4s).This study reports the first high-resolution nuclear magnetic resonance(NMR)solution structure of the major TMPRSS2-G4,which consists of a three-tetrad core parallel-stranded G4.Both 3′and 5′flanking regions form well-defined capping structures stabilized by multiple hydrogen bonds.Importantly,we found that berberine,an antiviral alkaloid,strongly binds to the major TMPRSS2-G4 and determined its binding complex structure with TMPRSS2-G4 at a 2∶1 binding stoichiometry.Each berberine molecule recruits an adjacent flanking residue,forming a coplanar structure superimposed on two outer G-tetrads.Moreover,we demonstrated that the major TMPRSS2-G4 can stably form within a longer deoxyribonucleic acid(DNA)context and be targeted by small molecules to inhibit DNA polymerase activity.Overall,this study provides structural insights into the recognition mechanism of small molecules by the major TMPRSS2-G4 and may facilitate the development of novel antiviral therapeutics targeting TMPRSS2-G4.
基金National Science Fund for Distinguished Young Scholars,Grant/Award Number:52225403State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,Grant/Award Number:SDGZK2404Fundamental Research Funds for the Central Universities,Grant/Award Number:2023KYJD1006。
文摘Hydrochloric acid(HCl)extensively exists in deep underground projects,arising from the transportation of industrial raw materials or fracturing fluids of petroleum engineering.It results in corrosion,which can significantly impact the stability of surrounding rock structures.Therefore,in-depth analysis of the degradation of rock corroded by the HCl solution is an essential task for underground engineering.In this study,the granite specimens are initially treated with the HCl solution with various concentrations.Then,the tests and analyses,such as electrical conductivity(EC)measurements,mineral composition assays,and Brazilian splitting tests,are employed to investigate the corrosion mechanism of the HCl solution.Our results and findings are generally as follows:(1)As the immersion time increases,the EC exhibits a relatively high level at pH value of 1,a decreasing trend at pH value of 3,and an increasing trend at pH value of 5 and 7.(2)The HCl solutions with various concentration have different effect on mineral composition,characterized by an increase in proportion of SiO_(2) and a reduction in proportion of Na_(2)O,Al_(2)O_(3),K_(2)O,MgO,and CaO,as the solution pH value decreases.(3)After immersion in the solutions with pH values of 1,3,and 5,the tensile strength of the granite decreases by 23.85%,20.84%,and 20.24%;the average stiffness of the specimen decreases by 29.29%,23.43%,and 11.97%;the proportion of releasable energy increases by 6%,4%,and -2%;the releasable energy decreases by 54.96%,26.09%,and 14.52%;and the dissipated energy decreases by approximately 68.85%,41.39%,and 5.41%,respectively.(4)The evolution of physical and mechanical properties of the immersed granite specimen can be analyzed from a chemical aspect.The corrosive action of HCl cleaves Si–O and Al–O chemical bonds within the granite,particularly altering the tetrahedral structures of its silicate components.This process involves breaking existing chemical bonds and the formation of new ones,ultimately destroying the silicate molecular structures.As the concentration of HCl increases,the rate of these reactions accelerates,progressively weakening the chemical bonds and consequently deteriorating the mechanical characteristics of the granite.These findings can deepen our knowledge about the corrosion effect of HCI solutions on natural surrounding rocks and serve as references for further research on rock corrosion mechanisms in underground engineering.
基金supported by the National Natural Science Foundation of China(Nos.51576097,51976089)the Funding for Outstanding Doctoral Dissertation in Nanjing University of Aeronautics and Astronautics,China(No.BCXJ24-05)the Aeronautical Science Foundation of China(No.2023L060052001).
文摘Quick and accurate determination of the optimal synchrophase angle is crucial for synchrophasing control of multi-propeller aircraft with low noise.This paper proposes a novel noise prediction and optimization strategy,developing a continuous and accurate noise prediction model and obtaining its minimum by solving the Hessian matrix and Fourier-Frobenius matrix.Firstly,a novel propeller noise prediction method uses acoustic simulation pressure signals and improved propeller signatures theory to accurately estimate noise for all synchrophase angles and receiving points.Secondly,a novel optimization approach is proposed to solve the analytical solution of the minimum propeller noise:(A)A noise objective function is established,and use its first derivatives’zeros and Hessian matrix to determine the function minimum.(B)A novel Euler formula transform method is proposed to convert trigonometric polynomials into algebraic polynomials,changing the zeros of the former into those of the latter.(C)Utilize the Fourier-Frobenius matrix method to solve the zeros of algebraic polynomials.To assess the computation time and accuracy,a turboprop aircraft with two six-bladed propellers was analyzed using the computational fluid dynamics and acoustic analogy method,providing acoustic pressure signals at 20 receivers for noise prediction and optimization.The Durand-Kerner and Fourier-Frobenius matrix methods were compared.Results demonstrate that improved propeller signatures theory is more accurate,and the Hessian matrix+Fourier-Frobenius matrix method is faster and more precise than the Hessian matrix+Durand-Kerner method.
基金supported by Natural Science Foundation of Xiamen,China(No.3502Z20227232)the STS Project of Fujian-CAS(No.2023T3018)Bureau of International Cooperation,Chinese Academy of Sciences(No.322GJHZ2022035MI).
文摘Anammox bacteria in constructed wetlands(CWs)play pivotal role in sustainable nitrogen transformation,yet existing studies lack comprehensive analysis of environmental gradients and microbial interactions,both key factors in anammox bacteria enrichment.This study investigated the mechanisms driving anammox bacteria enrichment in lab-scale simulated CWs treating high-nitrogen wastewater,focusing on bacterial community re-sponses across wetland layers with various strategies,including continuous up-flow influent,nitrogen loading increase,effluent recirculation,intermittent influent,and anammox bacteria inoculation.Results showed that total relative and absolute abundances of anammox bacteria ranged from 0.77%to 12.50%and from 0.13 to 6.46×10^(7) copies/g,respectively.Dissolved oxygen and pH had significant positive correlations with the absolute abundance of anammox bacteria,while organic matter and nitrate negatively impacted their relative abundance.Permutational multivariate analysis of variance indicated that spatial heterogeneity explained more variation in anammox bacteria abundance(43.44%)compared to operational strategies(8.58%).In terms of microbial interactions,60 dominant species exhibited potential correlations with anammox bacteria,comprising 170 interactions(105 positive and 65 negative),which suggested that anammox bacteria generally foster cooperative relationships with dominant bacteria.Notably,significant interspecies interactions were observed between Candidatus Kuenenia(dominant anammox bacteria in CWs)and species within the genera Chitinivibrio-nia and Anaerolineaceae,suggesting that microbial interactions primarily manifest as indirect facilitative effects rather than direct mutualistic relationships.Given that the Normalized Stochasticity Ratio in CWs were<50%,this study inferred that environmental gradients have greater influence on anammox bacteria than microbial interactions.
基金supported by the MATRICES,SERB-DST,New Delhi,India(No.MTR/2021/000002).
文摘In this paper,we consider a robust semi-infinite interval-valued optimization problem with inequality constraints having an uncertain parameter.The parametric representation of the aforesaid problem is also considered in order to derive the necessary and sufficient optimality conditions.Furthermore,we formulate a mixed-type dual problem and derive duality results which associate the robust weak efficient solution of the primal and its dual problems.Several examples are given to illustrate the results in the manuscript.
基金Project(52401064)supported by the National Natural Science Foundation of ChinaProject(24B0172)supported by the Scientific Research Fund of Hunan Provincial Education Department,ChinaProject(XDCX2024Y273)supported by the Postgraduate Scientific Research Innovation Project of Xiangtan University,China。
文摘Zn-Mn alloys are regarded as promising biodegradable metals for orthopedic applications owing to their moderate degradation rates and favorable osteogenic properties.However,the presence of a substantial number of second-phase particles in Zn-based alloys might induce severe localized degradation via micro-coupling corrosion,thereby compromising the mechanical integrity of the alloy during in vivo tissue regeneration.In this study,high pressure solid solution(HPSS)treatment was conducted at 5 GPa and 380℃ for 1 h to fabricate Zn-0.5 Mn alloys.Microstructural characterization revealed that the HPSS treatment facilitated the formation of a supersaturated solid solution by completely dissolving theζ-MnZn_(13) phase into theα-Zn matrix.The resultant strengthening mechanisms,including supersaturated solid solution strengthening,grain-size strengthening,and dislocation strengthening,collectively enhanced the compressive yield strength(σ_(cys))of the Zn-0.5 Mn alloy to about 183.7 MPa,approximately three times that of the as-cast(AC)Zn-0.5 Mn alloy.Moreover,compared with the AC alloy,the HPSS Zn-0.5 Mn alloy exhibited uniform degradation behavior with a markedly reduced degradation rate.
基金Supported by the National Natural Science Foundation of China(Grant Nos.12361040,12061064)the National Science Foundation of Gansu Province(Grant No.22JR5RA264)State Scholarship Fund(Grant No.20230862021).
文摘In this article,we show the existence,uniqueness and stability of bounded solutions to the following quasilinear problems with mean curvature operator(φ'(x′(t)))′=f(t,x),t≥t_(0),lim_(t→∞)x(t)=ψ_(0),lim_(t→∞)x′(t)e^(t)=0,where t_(0) and ψ_(0) are real constants,φ(s)=s/√1−s^(2),s∈R with s∈(−1,1),f:[t_(0),∞)×R→R satisfies the Lipschitz or Osgood-type conditions.
基金supported by the National Natural Science Foundation of China(No.52433009)the Fundamental Research Funds for the Central Universities(No.GK202501005)the State Key Laboratory of Polymer Science and Technology(No.PST-KF2025-07)。
文摘The scalable fabrication of stretchable conjugated polymer films via solution printing is essential for their practical application in largearea wearable electronics.However,the printed conjugated polymer films typically exhibit high crystallinity,limiting their mechanical deformability.Herein,we propose a plasticizer-assisted printing strategy to simultaneously enhance the stretchability and electrical performance of films based on the conjugated polymer poly(3-(5-(5-methylselenophen-2-yl)thiophen-2-yl)-6-(5-methylthiophen-2-yl)-2,5-bis(4-octyltetradecyl)-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione)(P(TDPP-Se)).The incorporation of a plasticizer trioctyl trimellitate(TOTM)promotes P(TDPP-Se)aggregation in initial solution,facilitates chain alignment under flow field,and shorten solidification process,thereby restricting randomly polymer crystallization.Consequently,a low-crystallinity film with favorable edge-on orientation,strong chain alignment and improved chain dynamics is realized,which effectively alleviates crystallites fragmentation and crack propagation under large strain.The TOTM-plasticized film exhibits approximately 2-fold improvements in fracture strain and charge mobility,along with superior mobility retention under 100%strain in comparison to the neat film.This study provides a feasible approach for microstructure control in printed stretchable conjugated polymer film.
文摘Circumlunar abort trajectories constitute a vital contingency return strategy during the translunar phase of crewed lunar missions.This paper proposes a methodology for constructing the solution set of the circumlunar abort trajectory and leverages its advantageous properties to address the optimization design problem of abort trajectories.Initially,a solution set of all feasible abort trajectories,originating from an abort point on the nominal trajectory and complying with fundamental reentry constraints,is formulated through the introduction of two novel design parameters.Subsequently,the geometric characteristics of the solution set,as well as the distributional properties of key iterative constraint responses,including flight time and velocity increment,are analyzed.Finally,the characteristics exhibited in the solution set are employed to directly identify the design parameters of the abort trajectories with minimum flight time and velocity increment,thereby providing solutions to two distinct types of optimization problems.The simulation results for a variety of nominal trajectories,encompassing the reconstruction and redesign of the Apollo13 abort trajectory,validate the proposed method,demonstrating its ability to directly generate optimal abort trajectories.The method proposed in this paper investigates feasible abort trajectories from a global perspective,providing both a framework and convenience for mission planning and iterative optimization in abort trajectory design.
基金funded by the National Key R&D Pro-gram of China (No.2023YFC3903903)the Science and Technology Innovation Talent Program of Hubei Province,China (No.2022EJD002).
文摘The use of Al-V alloys as intermediate additives is pivotal for producing high-performance Ti alloys.Traditionally,the synthesis of these alloys relies on high-purity V_(2)O_(5),with sodium metavanadate as an essential intermediate in V_(2)O_(5)production.This study explores an alternative approach utilizing sodium metavanadate directly,offering an aluminothermic process to alleviate the environmental impact and reduce the time required for V_(2)O_(5)preparation.Al-V alloys are synthesized using sodium metavanadate derived from a shale V-rich solution,and the impurity-migration behaviors are comprehensively analyzed,specifically focusing on Fe,Al,and Na.The result sreveal that Al interacts with CaO to form a slag phase that is different from the alloy,whereas Na undergoes a sequence of reductions (NaVO_(3)→Na_(2)V_(2)O_(5)→NaVO_(2)→Na)and volatilizes at 25-1200℃,thereby avoiding incorporation into the alloy.Fe,reduced by Al,enriches the alloy phase and induces a phase transition(Al-V→Al-Fe→Fe-V)in the presence of excess Fe.Sodium metavanadate(Fe≤0.05wt%)derived from the shale V-rich solution enables the production of a uniform AlV65 alloy with 66.56wt%V,33.14wt%Al,0.08wt%Fe,0.07wt%C,0.02wt%N,and 0.12wt%O.These results establish a streamlined,efficient framework for the future preparation of Al-V alloys from shale V-rich solutions.
基金supported by the National Natural Science Foundation of China(52074004 and 51604003)Anhui Provincial Natural Science Foundation(2508085Y032).
文摘Acid is commonly used to separate phosphorus-containing solid solutions from steelmaking slag.However,the acid leaching solution obtained from this process cannot be directly utilized and thus requires purification.The effect of different conditions on the calcium and iron removal characteristics of modified steelmaking slag leaching solution was investigated.Additionally,the removal mechanism was analyzed by thermodynamic calculations.The results indicated that the addition of soybean straw ash in steelmaking slag modification enabled K_(2)O to enter the phosphorus-containing solid solution,promoting phosphorus enrichment.Valuable elements such as phosphorus and potassium were more easily dissolved in the mixed acid.The oxalic acid concentration had a significant effect on the calcium removal rate,whereas the effects of temperature,stirring rate,and time on the calcium removal rate were minor.The main component of the calcium removal precipitate was CaC_(2)O_(4)·H_(2)O,with a removal rate up to 94.48%.During the iron removal process,when the pH value of the solution was low,Fe^(3+)mainly reacted to form the iron hydroxide precipitate for removal.Increasing the pH value of the solution would cause Fe^(3+)to combine with H_(2)PO_(4)^(-),forming FePO_(4)·2H_(2)O precipitate,leading to a reduction in the phosphorus content of the leaching solution.
基金the financial support from the National Natural Science Foundation of China(Nos.22377097,22307036,22074114)Natural Science Foundation of Hubei Province of China(Nos.2020CFB623,2021CFB556)Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education(No.LCX202305)。
文摘The detection of amino acid enantiomers holds significant importance in biomedical,chemical,food,and other fields.Traditional chiral recognition methods using fluorescent probes primarily rely on fluorescence intensity changes,which can compromise accuracy and repeatability.In this study,we report a novel fluorescent probe(R)-Z1 that achieves effective enantioselective recognition of chiral amino acids in water by altering emission wavelengths(>60 nm).This water-soluble probe(R)-Z1 exhibits cyan or yellow-green luminescence upon interaction with amino acid enantiomers,enabling reliable chiral detection of 14 natural amino acids.It also allows for the determination of enantiomeric excess through monitoring changes in luminescent color.Additionally,a logic operation with two inputs and three outputs was constructed based on these optical properties.Notably,amino acid enantiomers were successfully detected via dual-channel analysis at both the food and cellular levels.This study provides a new dynamic luminescence-based tool for the accurate sensing and detection of amino acid enantiomers.
