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
The separation of propylene(C_(3)H_(6))and propane(C_(3)H_(8))presents a significant industrial challenge due to their similar molecular dimensions and physicochemical properties.Among various separation methods,molec...The separation of propylene(C_(3)H_(6))and propane(C_(3)H_(8))presents a significant industrial challenge due to their similar molecular dimensions and physicochemical properties.Among various separation methods,molecular sieving emerges as the most promising approach,but it will be significantly compromised at high temperatures due to the significant thermal motion.Here,we report a thermally robust zinc-based metal-organic framework(MOF)that can be synthesized on sub-kilogram scale and achieve exceptional C_(3)H_(6)/C_(3)H_(8) separation performances across a broad temperature range(298–353 K).Unlike conventional MOFs suffering from thermal lattice expansion to give poorer selectivity,this new MOF gives the adsorption capacity of C_(3)H_(6)essentially unchanged and that of C_(3)H_(8) negligible at elevated temperatures,outperforming most state-of-the-art adsorbents,in virtue of multiple hydrogen bonds at the aperture.Column breakthrough experiments confirmed the excellent separation capability,and showed no performance degradation over multi-round adsorption-desorption cycles at 353 K.This study addresses the critical challenge of the trade-off between temperature and selectivity in adsorptive separation,which offers new insights into the design of porous structures for highly effective separation at high temperatures.展开更多
Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a syste...Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a systematic review of the enrichment characteristics,occurrence modes,and comprehensive utilization potential of these critical metals in coal.Globally,the distribution of these metal resources exhibits significant regional heterogeneity.While the concentration in most coals falls below industrial cut-off grades,anomalous enrichment in specific coal basins results in Li,Ga,Ge,and REE concentrations far exceeding global averages,highlighting their considerable potential as unconventional metal deposits.The occurrence modes of these metals are diverse:Li is primarily hosted in mineral phases;Ga exists in inorganic,organic,and complex forms;Ge shows a strong association with organic matter;and REE are mainly present in adsorbed/isomorphic forms within clay minerals,while also displaying organic affinity.Direct extraction of metals from raw coal is often cost-prohibitive;effective recovery is therefore more feasible when integrated with coal processing.Metals are further enriched in solid wastes such as coal gangue,fly ash,and bottom ash,from which recovery is more economically and technically viable.Current comprehensive utilization primarily employs integrated mineral processing-hydrometallurgy approaches.Future research should focus on elucidating the precise occurrence forms of metals in coal and solid wastes,optimizing pre-treatment methods,and selecting effective activators and leachants.Advancing the synergistic extraction and green recovery of multiple associated resources from coal and its by-products is essential for achieving high-value,comprehensive utilization of coal-based resources.展开更多
The dependence of interface structure and mechanical properties on the modulation layer thickness of VN/TiN−Ni nano-multilayered films deposited on Si substrates using a reactive magnetron sputtering technique was sys...The dependence of interface structure and mechanical properties on the modulation layer thickness of VN/TiN−Ni nano-multilayered films deposited on Si substrates using a reactive magnetron sputtering technique was systematically investigated. The films were characterized using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, and nanoindentation. The results show that the TiN−Ni layer grows epitaxially on the VN layer, forming a coherent interface between the two sublayers. When the deposition time ratio of the two sublayers (TTiN−Ni꞉TVN) is 10꞉12, the films exhibit remarkable mechanical properties, with hardness, elastic modulus, and fracture toughness values of 25.9 GPa, 317 GPa, and 1.88 MPa·m^(1/2), respectively. Meanwhile, fracture toughness is improved by approximately 50% compared to the VN monolithic film. This enhancement is attributed to the coherent interface between the sublayers and the phase separation in the TiN−Ni layer.展开更多
This paper examines a model that combines vortex generators and leading-edge tubercles for controlling the laminar separation bubble(LSB)over an airfoil at low Reynolds numbers(Re).This new concept of passive flow con...This paper examines a model that combines vortex generators and leading-edge tubercles for controlling the laminar separation bubble(LSB)over an airfoil at low Reynolds numbers(Re).This new concept of passive flow control technique utilizing a tubercle and vortex generator(VG)close to the leading edge was analyzed numerically for a NACA0015 airfoil.In this study,the Shear Stress Transport(SST)turbulence model was employed in the numerical modelling.Numerical modelling was completed using the ANSYS-Fluent 18.2 solver.Analyses were conducted to investigate the flow pattern and understand the underlying LSB control phenomena that enabled the new passive flow control method to provide this significant performance benefit.The findings indicated that the new concept of passive flow control technique suppressed the formation of an LSB at the suction surface of the NACA0015 airfoil,resulting in a higher lift coefficient and improved aerodynamic performance.Improvements in LSB dynamics and aerodynamic performance through the passive flow control method lead to increased energy output and enhanced stability.展开更多
Developing advanced polymeric materials with enhanced mechanical properties and functionalities has been a long-standing goal in materials science.Recently,supramolecular polymeric materials(SPMs)have drawn increased ...Developing advanced polymeric materials with enhanced mechanical properties and functionalities has been a long-standing goal in materials science.Recently,supramolecular polymeric materials(SPMs)have drawn increased attention due to their unique properties and potential applications in self-healing,shape memory,sensors,and flexible electronics.Here,we develop an ionic cluster-optimized microphase separation strategy to enhance the toughening and energy dissipation capabilities of polydisulfide-based supramolecular polymers.The mechanical properties,including Young's modulus and toughness,are significantly improved by integrating the quadruple H-bonding 2-ureido-4-pyrimidone(UPy)induced microphase separation with iron(III)-to-carboxylate ionic clusters.By combining established chemical approaches with adjustable polymer phase ratios,it is revealed that the synergistic effect of these factors expands the interchain spacing,facilitates the formation of microphase domains,and enhances the tolerance of polythioctic acid-based polymers to external mechanical and thermal stimuli,meeting the practical requirements for industrial plastic applications.Moreover,the UPy-functionalized polymers incorporating iron carboxylate clusters exhibit good one-way shape memory behavior with practical applicability at a relatively low recovery temperature.Our work demonstrates a novel strategy for constructing industrially viable shape memory dynamic SPMs and paves the way for future innovations in developing SPMs.展开更多
The removal of trace plutonium(Pu)from uranium products and organic wastes during spent nuclear fuel reprocessing remains a critical challenge,resulting in excessive plutonium content in uranium products and waste org...The removal of trace plutonium(Pu)from uranium products and organic wastes during spent nuclear fuel reprocessing remains a critical challenge,resulting in excessive plutonium content in uranium products and waste organic liquid.Currently,most organic ligands with selective separation functions are lipophilic,while research on water-soluble,highly selective ligands is relatively scarce,and there are also few reports on the single crystal of these ligands coordinating with plutonium.Herein,a hydrophilic multiamide ligand,N,N,N′,N″,N″-hexaethyl-nitrilotriacetamide(NTAamideC2),was synthesized and evaluated for its Pu(Ⅳ)back-extraction efficiency under harsh conditions.Systematic experiments revealed that NTAamideC2 achieved>99%Pu(Ⅳ)back-extraction rate within 15 min across a wide nitric acid concentration range(0-5 M),even with elevated dibutyl phosphate(DBP≤20000 ppm).Remarkably,the separation factor(SFPu/U)reached 767 at 1.5 M HNO_(3),demonstrating exceptional selectivity over uranium(Ⅵ).Spectrophotometric titration and DFT calculations confirmed the formation of 1:1 and 1:2 Pu(Ⅳ)-NTAamideC2 complexes,with log β values of 7.42±0.01 and 13.23±0.02,respectively.Single-crystal X-ray diffraction analysis of{[Pu_(2)(H_(2)O)_(2)(NTAamideC2)_(4)](H_(2)O)_(2)(NO_(3))(ClO_(4))_(7)}revealed a nine-coordinated PuO_(7)N_(2)geometry,where two NTAamideC2 molecules bind via six O and two N atoms.Compared to conventional agents(AHA/HSC),NTAamideC2 exhibited superior acid tolerance and selectivity,aligning with the CHON principle for sustainable nuclear waste management.This work provides a robust strategy for Pu(Ⅳ)removal in uranium purification cycles and advances fundamental insights into Pu coordination chemistry,offering significant potential for industrial nuclear fuel reprocessing.展开更多
Herein,we demonstrated the integration of BiVO_(4)-based photoanode with metallic Zn cathode for high-performance CO_(2)reduction,and a record CO production rate of 113.32μmol cm^(−2)h^(−1)with a FECO of 90.57%has be...Herein,we demonstrated the integration of BiVO_(4)-based photoanode with metallic Zn cathode for high-performance CO_(2)reduction,and a record CO production rate of 113.32μmol cm^(−2)h^(−1)with a FECO of 90.57%has been achieved under simulated sunlight(AM 1.5 G,100 mW),accompanying with an excellent stability.More importantly,the direct observation of spatial charge separation/transfer and dynamic surface catalysis for both H_(2)O oxidation and CO_(2)reduction has been firstly achieved by the combination of in situ X-ray photoelectron spectroscopy(IS-XPS)with Fourier transform infrared reflection(IS-FTIR).Under light irradiation,the electron-hole pairs have been generated on BiVO_(4) photoanode,and holes rapidly transfer to photoanode surfaces for participating in oxygen evolution reaction(OER)through the formation of*OH and*OOH intermediates.Simultaneously,the proton-coupled electron transfer to the Zn cathode surfaces drive the reduction of adsorbed CO_(2)molecules into CO via the formation*COOH and*CO intermediates.Thereby,this work offers new insights into fundamental understanding of CO_(2)reduction process,which facilitates the future development of highly efficient carbon fixation systems.展开更多
Sustainable development for our life is important task,which is driven by key materials and technologies.In this roadmap,we discuss three main aspects in addressing environmental questions,green chemical processes and...Sustainable development for our life is important task,which is driven by key materials and technologies.In this roadmap,we discuss three main aspects in addressing environmental questions,green chemical processes and energy challenges.They are included,such as gas treatment and separation,wastewater treatment,waste gas treatment,solid waste treatment,lithium extraction,hydrogen production,water splitting,CO_(2) reduction,photocatalytic clean technologies,plastic degradation,fuel cells,lithium batteries,sodium batteries,aqueous batteries,solid state batteries,metal air batteries and supercapacitors.Their status,challenges,progress and future perspectives are also discussed.We hope that this paper can give clear views on sustainable development in materials and technologies.展开更多
Conventional electrolytic methods for separating chemically similar lanthanides(Ln)and actinides(An)are limited by thermodynamics and slow reaction kinetics,restricting their efficiency in rare-earth refining and nucl...Conventional electrolytic methods for separating chemically similar lanthanides(Ln)and actinides(An)are limited by thermodynamics and slow reaction kinetics,restricting their efficiency in rare-earth refining and nuclear fuel recycling.Herein,we report an electroextraction and oxidative back-extraction(EOB)strategy utilizing a LiCl-KCl-KAlCl_(4) molten salt that overcomes these limitations by leveraging divergent interfacial reactivity.The EOB process achieves an exceptional separation factor for Ln/An(>1000),while simultaneously increasing the separation rate by at least one order of magnitude.Through in-situ synchrotron radiation X-ray micro-computed tomography(SR-μCT)and X-ray diffraction(SR-XRD),we capture selective oxidation-induced destabilization of Ln-Al alloys while actinides retain phase stability-directly visualizing the electrochemical alloy transition mechanism.This research redefines the separation of f-block elements in molten salt systems and introduces a multimodal approach to investigating transient interfacial phenomena that are usually inaccessible to conventional metallurgical diagnostics under extreme conditions.展开更多
Airless tires are essential for enhancing the safety,reliability,and convenience of maintenance of electric bicycles.Polyurethane(PU)is considered a promising candidate for such applications owing to its versatile pro...Airless tires are essential for enhancing the safety,reliability,and convenience of maintenance of electric bicycles.Polyurethane(PU)is considered a promising candidate for such applications owing to its versatile properties.However,their use is limited by insufficient heat resistance and excessive dynamic heat generation under cyclic loading.In this study,star-shaped trifunctional polypropylene glycerol(PPG3)was incorporated into conventional poly(tetramethylene glycol)(PTMG)and 4,4'-methylenediphenyl diisocyanate(MDI)-based systems to construct microporous star-shaped casting polyurethanes(SCPU),with water serving as a green foaming agent.Unlike conventional small-molecule trifunctional crosslinkers that create junctions within hard segment domains,PPG3 introduces long flexible arms between the hard segments,anchoring the crosslinking points at its molecular core.The large steric hindrance of PPG3 effectively suppresses soft segment crystallization and lowers the degree of microphase separation,whereas the crosslinked network restricts chain mobility,thereby reducing dynamic heat generation.These structural features also enhance the heat resistance,yielding a softening temperature of 183℃,which is 30.9%higher than that of polyurethane without PPG3.When applied to airless tires by casting SCPU into rubber treads,the fabricated hybrid airless tires achieved a rolling distance of over 3000 km under a load of 65 kg at 25km/h without structural failure,satisfying practical performance requirements.This strategy offers a simple,solvent-free,and environmentally friendly process,underscoring the potential of SCPU for scalable production of high-performance airless tires.展开更多
Biochar has been widely recognized as a promising solid CO_(2)adsorbent with economic and ecological benefits.Industrial CO_(2)emissions originate from diverse sources,while the pore structure and chemical functional ...Biochar has been widely recognized as a promising solid CO_(2)adsorbent with economic and ecological benefits.Industrial CO_(2)emissions originate from diverse sources,while the pore structure and chemical functional groups of biochar exhibit varying degrees of influence on CO_(2)adsorption and separation performance under different adsorption conditions.Therefore,exploring the matching relationship between the physicochemical properties of biochar and its adsorption and separation performance at different adsorption conditions is essential for the development and optimization of carbon-based adsorbents.This study selected the high-performance extreme gradient boosting(XGB)algorithm from various algorithms and utilized it to develop CO_(2),N_(2),CH_(4)adsorption prediction models.Based on this,coupled prediction models were developed for CO_(2)/N_(2)and CO_(2)/CH_(4)adsorption selectivity.Furthermore,feature importance and partial dependence analysis were performed using SHAP values.The results indicate that during CO_(2)adsorption,the influence of the pore structure of biochar outweighs that of its chemical composition.Specifically,the pore structure of 0.4–0.6 nm is the most important property influencing CO_(2)adsorption at low and medium pressure(0–0.6 bar),and the pore structure of 0.6–0.8 nm,as well as the specific surface area contribute the most at high pressure(0.6–1 bar).During CO_(2)selective separation,the CO_(2)/N_(2)mixture is primarily separated through the selective adsorption of CO_(2)by nitrogen functional groups.In contrast,for CO_(2)/CH_(4)mixtures,pore structure<1 nm plays a more critical role in determining adsorption selectivity.In addition,molecular simulation studies further revealed the adsorption filling mechanisms of CO_(2)molecules within different pore sizes and functional groups.Finally,nitrogen-doped biochar was synthesized using de-alkalize lignin as the precursor,KOH as the activating agent,and urea as the nitrogen dopant.CO_(2),N_(2),and CH_(4)isothermal adsorption experiments were conducted,and the experimental results confirmed that the developed prediction models exhibit high accuracy(R^(2)>0.9).展开更多
Recently,the Standardization Administration of China issued Announcement No.1 of 2026,officially approving the establishment of the Subcommittee 1 on Nonwoven Material of National Technical Committee 606 on Technical ...Recently,the Standardization Administration of China issued Announcement No.1 of 2026,officially approving the establishment of the Subcommittee 1 on Nonwoven Material of National Technical Committee 606 on Technical Textiles of Standardization Administration of China(SAC/TC606/SC1)and the Subcommittee 2 on Filtration and Separation Textiles of National Technical Committee 606 on Technical Textiles of Standardization Administration of China(SAC/TC606/SC2).The formation of these two subcommittees marks a crucial step in the standardization development of China's industrial textiles sector in specialized fields.展开更多
Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or ...Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or attitude instability,seriously compromising mission reliability.To address this engineering challenge,this paper proposes a multi-point low-impact locking/release mechanism based on the mobility model and energy conversion strategy.Through establishing a DOF constraint framework system,this paper systematically analyzes the energy transfer and conversion characteristics during the wing separation process,reveals the generation mechanism of impact loads,and conducts research on low-impact design based on energy conversion strategy.Building on this foundation,a single-point locking/release mechanism employing parallel trapezoidal key shaft structure was designed,which increases frictional contact time and reduces the energy release rate,thereby achieving low-impact characteristics.The mechanism's performance was validated through physical prototype development and systematic functional testing(including unlocking force,synchronization,and impact tests).Experimental results demonstrate:(1)Under 14 kN preload condition,the maximum unlocking force was only 92.54 N,showing a linear relationship with preload that satisfies the"strong-connection/weak-unlock"design requirement;(2)Wing separation was completed within 46 ms,with synchronization time difference among three separation mechanisms stably controlled within 12-14 ms,proving rapid and reliable operation;(3)The unlocking impact acceleration ranged between 26 and 73 g,below the 100 g design limit,confirming the effectiveness of the energy conversion strategy.The proposed low-impact locking/release mechanism design method based on energy conversion strategy resolves the traditional challenges of high impact and synchronization deficiencies.The synergistic optimization mechanism of"structural load reduction and performance improvement"provides a highly reliable technical solution for wing separable mechanisms while offering novel design insights for wing connection/separation systems engineering.展开更多
Developing a chiral material as versatile and universal chiral stationary phase(CSP) for chiral separation in diverse chromatographic techniques simultaneously is of great significance.In this study,we demonstrated fo...Developing a chiral material as versatile and universal chiral stationary phase(CSP) for chiral separation in diverse chromatographic techniques simultaneously is of great significance.In this study,we demonstrated for the first time that a chiral metal-organic cage(MOC),[Zn_(6)M_(4)],as a universal chiral recognition material for both multi-mode high-performance liquid chromatography(HPLC) and capillary gas chromatography(GC) enantioseparation.Two novel HPLC CSPs with different bonding arms(CSP-A with a cationic imidazolium bonding arm and CSP-B with an alkyl chain bonding arm) were prepared by clicking of functionalized chiral MOC [Zn_(6)M_(4)] onto thiolated silica via thiol-ene click chemistry.Meanwhile,a capillary GC column statically coated with the chiral MOC [Zn_(6)M_(4)] was also fabricated.The results showed that the chiral MOC exhibits excellent enantioselectivity not only in normal phase HPLC(NP-HPLC) and reversed phase(RP-HPLC) but also in GC,and various racemates were well separated,including alcohols,diols,esters,ketones,ethers,amines,and epoxides.Importantly,CSP-A and CSP-B are complementary to commercially available Chiralcel OD-H and Chiralpak AD-H columns in enantioseparation,which can separate some racemates that could not be or could not well be separated by the two widely used commercial columns,suggesting the great potential of the two prepared CSPs in enantioseparation.This work reveals that the chiral MOC is potential versatile chiral recognition materials for both HPLC and GC,and also paves the way to expand the potential applications of MOCs.展开更多
Objective:To analyze the impact of maternal-infant separation on the physical and mental state of high-risk pregnancy patients and explore the clinical efficacy of targeted nursing interventions.Methods:A total of 80 ...Objective:To analyze the impact of maternal-infant separation on the physical and mental state of high-risk pregnancy patients and explore the clinical efficacy of targeted nursing interventions.Methods:A total of 80 high-risk pregnancy patients treated in our hospital from January 2023 to January 2024 were selected as the study subjects.These patients were randomly divided into an observation group and a control group(40 cases each)using a random number table.The control group received routine high-risk pregnancy nursing care,while the observation group received specialized maternal-infant separation nursing interventions in addition to routine care.The psychological and physiological states and nursing satisfaction of the two groups were compared before and after the intervention.Results:The SAS scores,SDS scores,and sleep quality scores of the observation group were significantly lower than those of the control group,with statistically significant differences(p<0.05).The incidence of postpartum hemorrhage in the observation group was significantly lower than that in the control group,and the initiation time of lactation was significantly earlier than that in the control group,with both differences being statistically significant(p<0.05).The nursing satisfaction of the observation group was significantly higher than that of the control group(80%vs.32/40),with a statistically significant difference(p<0.05).Conclusion:Maternal-infant separation exacerbates anxiety and depression in high-risk pregnancy patients,reduces sleep quality,increases the risk of postpartum hemorrhage,and delays the initiation of lactation.Specialized nursing interventions for maternal-infant separation can improve the physical and mental state of high-risk pregnancy patients,reduce the incidence of postpartum complications,and enhance nursing satisfaction,making them worthy of clinical application and promotion.展开更多
Vehicle-induced response separation is a crucial issue in structural health monitoring(SHM).This paper proposes a block-wise sliding recursive wavelet transform algorithm to meet the real-time processing requirements ...Vehicle-induced response separation is a crucial issue in structural health monitoring(SHM).This paper proposes a block-wise sliding recursive wavelet transform algorithm to meet the real-time processing requirements of monitoring data.To extend the separation target from a fixed dataset to a continuously updating data stream,a block-wise sliding framework is first developed.This framework is further optimized considering the characteristics of real-time data streams,and its advantage in computational efficiency is theoretically demonstrated.During the decomposition and reconstruction processes,information from neighboring data blocks is fully utilized to reduce algorithmic complexity.In addition,a delay-setting strategy is introduced for each processing window to mitigate boundary effects,thereby balancing accuracy and efficiency.Simulated signal experiments are conducted to determine the optimal delay configuration and to verify the algorithm’s superior performance,achieving a lower Root Mean Square Error(RMSE)and only 0.0249 times the average computational time compared with the original algorithm.Furthermore,strain signals from the Lieshi River Bridge are employed to validate the method.The proposed algorithm successfully separates the static trend from vehicle-induced responses in real time across different sampling frequencies,demonstrating its effectiveness and applicability in real-time bridge monitoring.展开更多
The GRACE(Gravity Recovery and Climate Experiment)space mission recorded temporal variation characteristics of the global gravity field at decadal timescales.The gravity data have been shown to capture the dynamics of...The GRACE(Gravity Recovery and Climate Experiment)space mission recorded temporal variation characteristics of the global gravity field at decadal timescales.The gravity data have been shown to capture the dynamics of flows within the outer core and their effects on the core-mantle boundary.We first aim to remove global surface process gravity signals from the GRACE data.We then construct the global core magnetic field according to the CHAOS-7 model.Finally,we apply the blind source separation method to decompose the processed gravity signals and core magnetic signals and compute the power spectral density of the gravity and magnetic field signals by using the Lomb-Scargle periodogram approach.We have discovered a signal cycle(of~6 years)in the principal components of the core magnetic and gravity signals,potentially as a result of deep Earth processes.The main principal components of the core magnetic and gravity signals reveal that the variation trends in the second-order time derivative of the core magnetic field are similar to those in the gravity field.After 2014,the second-order time derivative of the core magnetic field exhibited linear and rapid change characteristics,which were the same as the change in the gravity field and are consistent with existing research results.展开更多
Due to complex ion-ion and ion-membrane interactions, creating innovative membrane structures to acquire favorable ion mixing effect and high separation performance remains a big challenge. Herein, we design covalent ...Due to complex ion-ion and ion-membrane interactions, creating innovative membrane structures to acquire favorable ion mixing effect and high separation performance remains a big challenge. Herein, we design covalent organic framework(COF) scaffold membrane with gate-lane nanostructure for efficient Li^(+)/Mg^(2+) separation. COF nanosheets, serving as the scaffold, are intercalated by polyethyleneimine(PEI) to form the permeating layer. Subsequently, PEI on the surface reacts with 1,4-phenylene diisocyanate to form the polyurea gating layer. The gating layer, bearing tailored smaller pore size,affords high rejection to co-ions(Mg^(2+)) and thus high Li^(+)/Mg^(2+) selectivity. The permeating layer, with asymmetric charge and spatial nanostructure for creating individual lanes of Li^(+) and Cl~-, facilitates Li^(+) transport and thus high Li^(+) permeability. The optimum COF scaffold membrane exhibits the permeance of 11.5 L m^(-2) h^(-1)/bar^(-1) and true selectivity of 231.9 with Li^(+) enrichment of 120.2% at the Mg^(2+)/Li^(+) mass ratio of 50, exceeding the ideal selectivity of 80.5 and outperforming all ever-reported positively charged nanofiltration membranes. Our work may stimulate the further thinking about how to design the hierarchical membrane structure to achieve favorable ion mixing effect and break the membrane permeability-selectivity trade-off in chemical separations.展开更多
The accumulation and circulation of carbon and hydrogen contribute to the chemical evolution of ice giant planets.Species separation and diamond precipitation have been reported in carbon-hydrogen systems and have bee...The accumulation and circulation of carbon and hydrogen contribute to the chemical evolution of ice giant planets.Species separation and diamond precipitation have been reported in carbon-hydrogen systems and have been verified by static and shock compression experiments.Nevertheless,the dynamic formation processes underlying these phenomena remain insufficiently understood.In combination with a deep learning model,we demonstrate that diamonds form through a three-step process involving dissociation,species separation,and nucleation processes.Under shock conditions of 125 GPa and 4590 K,hydrocarbons decompose to give hydrogen and low-molecular-weight alkanes(CH_(4) and C_(2)H_(6)),which escape from the carbon chains,resulting in C/H species separation.The remaining carbon atoms without C-H bonds accumulate and nucleate to form diamond crystals.The process of diamond growth is associated with a critical nucleus size at which the dynamic energy barrier plays a key role.These dynamic processes of diamond formation provide insight into the establishment of a model for the evolution of ice giant planets.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supported by the National Natural Science Foundation of China(22475240,22090061,22488101)the State Key Laboratory of Catalysis(2024SKL-A-010)。
文摘The separation of propylene(C_(3)H_(6))and propane(C_(3)H_(8))presents a significant industrial challenge due to their similar molecular dimensions and physicochemical properties.Among various separation methods,molecular sieving emerges as the most promising approach,but it will be significantly compromised at high temperatures due to the significant thermal motion.Here,we report a thermally robust zinc-based metal-organic framework(MOF)that can be synthesized on sub-kilogram scale and achieve exceptional C_(3)H_(6)/C_(3)H_(8) separation performances across a broad temperature range(298–353 K).Unlike conventional MOFs suffering from thermal lattice expansion to give poorer selectivity,this new MOF gives the adsorption capacity of C_(3)H_(6)essentially unchanged and that of C_(3)H_(8) negligible at elevated temperatures,outperforming most state-of-the-art adsorbents,in virtue of multiple hydrogen bonds at the aperture.Column breakthrough experiments confirmed the excellent separation capability,and showed no performance degradation over multi-round adsorption-desorption cycles at 353 K.This study addresses the critical challenge of the trade-off between temperature and selectivity in adsorptive separation,which offers new insights into the design of porous structures for highly effective separation at high temperatures.
基金supported by the Key Support Project of Regional Innovation and Development Joint Fund of the National Natural Science Foundation of China(No.U24A2095).
文摘Coal serves not only as a crucial energy resource but also as a significant reservoir of critical metal elements,including Lithium(Li),Gallium(Ga),Germanium(Ge),and rare earth elements(REE).This paper provides a systematic review of the enrichment characteristics,occurrence modes,and comprehensive utilization potential of these critical metals in coal.Globally,the distribution of these metal resources exhibits significant regional heterogeneity.While the concentration in most coals falls below industrial cut-off grades,anomalous enrichment in specific coal basins results in Li,Ga,Ge,and REE concentrations far exceeding global averages,highlighting their considerable potential as unconventional metal deposits.The occurrence modes of these metals are diverse:Li is primarily hosted in mineral phases;Ga exists in inorganic,organic,and complex forms;Ge shows a strong association with organic matter;and REE are mainly present in adsorbed/isomorphic forms within clay minerals,while also displaying organic affinity.Direct extraction of metals from raw coal is often cost-prohibitive;effective recovery is therefore more feasible when integrated with coal processing.Metals are further enriched in solid wastes such as coal gangue,fly ash,and bottom ash,from which recovery is more economically and technically viable.Current comprehensive utilization primarily employs integrated mineral processing-hydrometallurgy approaches.Future research should focus on elucidating the precise occurrence forms of metals in coal and solid wastes,optimizing pre-treatment methods,and selecting effective activators and leachants.Advancing the synergistic extraction and green recovery of multiple associated resources from coal and its by-products is essential for achieving high-value,comprehensive utilization of coal-based resources.
基金financially supported by the National Natural Science Foundation of China(No.51971148)the Key Project Foundation of Hanjiang Normal University,China(No.XJ2024A09)+1 种基金the Excellent Young and Middle-aged Science and Technology Innovation Team Project in Higher Education Institutions of Hubei Province,China(No.T2020024)the Shanghai Engineering Research Center of High-Performance Medical Device Materials,China(No.20DZ2255500)。
文摘The dependence of interface structure and mechanical properties on the modulation layer thickness of VN/TiN−Ni nano-multilayered films deposited on Si substrates using a reactive magnetron sputtering technique was systematically investigated. The films were characterized using X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, and nanoindentation. The results show that the TiN−Ni layer grows epitaxially on the VN layer, forming a coherent interface between the two sublayers. When the deposition time ratio of the two sublayers (TTiN−Ni꞉TVN) is 10꞉12, the films exhibit remarkable mechanical properties, with hardness, elastic modulus, and fracture toughness values of 25.9 GPa, 317 GPa, and 1.88 MPa·m^(1/2), respectively. Meanwhile, fracture toughness is improved by approximately 50% compared to the VN monolithic film. This enhancement is attributed to the coherent interface between the sublayers and the phase separation in the TiN−Ni layer.
基金the Scientific Research Projects Unit of Erciyes University under contract no:FDS-2022-11532 and FOA-2025-14773.
文摘This paper examines a model that combines vortex generators and leading-edge tubercles for controlling the laminar separation bubble(LSB)over an airfoil at low Reynolds numbers(Re).This new concept of passive flow control technique utilizing a tubercle and vortex generator(VG)close to the leading edge was analyzed numerically for a NACA0015 airfoil.In this study,the Shear Stress Transport(SST)turbulence model was employed in the numerical modelling.Numerical modelling was completed using the ANSYS-Fluent 18.2 solver.Analyses were conducted to investigate the flow pattern and understand the underlying LSB control phenomena that enabled the new passive flow control method to provide this significant performance benefit.The findings indicated that the new concept of passive flow control technique suppressed the formation of an LSB at the suction surface of the NACA0015 airfoil,resulting in a higher lift coefficient and improved aerodynamic performance.Improvements in LSB dynamics and aerodynamic performance through the passive flow control method lead to increased energy output and enhanced stability.
基金supported by the National Natural Science Foundation of China(No.22375063)Science and Technology Commission of Shanghai Municipality(No.23JC140170O)the Fundamental Research Funds for the Central Universities.
文摘Developing advanced polymeric materials with enhanced mechanical properties and functionalities has been a long-standing goal in materials science.Recently,supramolecular polymeric materials(SPMs)have drawn increased attention due to their unique properties and potential applications in self-healing,shape memory,sensors,and flexible electronics.Here,we develop an ionic cluster-optimized microphase separation strategy to enhance the toughening and energy dissipation capabilities of polydisulfide-based supramolecular polymers.The mechanical properties,including Young's modulus and toughness,are significantly improved by integrating the quadruple H-bonding 2-ureido-4-pyrimidone(UPy)induced microphase separation with iron(III)-to-carboxylate ionic clusters.By combining established chemical approaches with adjustable polymer phase ratios,it is revealed that the synergistic effect of these factors expands the interchain spacing,facilitates the formation of microphase domains,and enhances the tolerance of polythioctic acid-based polymers to external mechanical and thermal stimuli,meeting the practical requirements for industrial plastic applications.Moreover,the UPy-functionalized polymers incorporating iron carboxylate clusters exhibit good one-way shape memory behavior with practical applicability at a relatively low recovery temperature.Our work demonstrates a novel strategy for constructing industrially viable shape memory dynamic SPMs and paves the way for future innovations in developing SPMs.
基金supported by the China Institute of Atomic Energy。
文摘The removal of trace plutonium(Pu)from uranium products and organic wastes during spent nuclear fuel reprocessing remains a critical challenge,resulting in excessive plutonium content in uranium products and waste organic liquid.Currently,most organic ligands with selective separation functions are lipophilic,while research on water-soluble,highly selective ligands is relatively scarce,and there are also few reports on the single crystal of these ligands coordinating with plutonium.Herein,a hydrophilic multiamide ligand,N,N,N′,N″,N″-hexaethyl-nitrilotriacetamide(NTAamideC2),was synthesized and evaluated for its Pu(Ⅳ)back-extraction efficiency under harsh conditions.Systematic experiments revealed that NTAamideC2 achieved>99%Pu(Ⅳ)back-extraction rate within 15 min across a wide nitric acid concentration range(0-5 M),even with elevated dibutyl phosphate(DBP≤20000 ppm).Remarkably,the separation factor(SFPu/U)reached 767 at 1.5 M HNO_(3),demonstrating exceptional selectivity over uranium(Ⅵ).Spectrophotometric titration and DFT calculations confirmed the formation of 1:1 and 1:2 Pu(Ⅳ)-NTAamideC2 complexes,with log β values of 7.42±0.01 and 13.23±0.02,respectively.Single-crystal X-ray diffraction analysis of{[Pu_(2)(H_(2)O)_(2)(NTAamideC2)_(4)](H_(2)O)_(2)(NO_(3))(ClO_(4))_(7)}revealed a nine-coordinated PuO_(7)N_(2)geometry,where two NTAamideC2 molecules bind via six O and two N atoms.Compared to conventional agents(AHA/HSC),NTAamideC2 exhibited superior acid tolerance and selectivity,aligning with the CHON principle for sustainable nuclear waste management.This work provides a robust strategy for Pu(Ⅳ)removal in uranium purification cycles and advances fundamental insights into Pu coordination chemistry,offering significant potential for industrial nuclear fuel reprocessing.
基金supported by the National Natural Science Foundation of China(21832005,22372181,22072168,22002175)Major Program of the Lanzhou Institute of Chemical Physics,CAS(ZYFZFX-3),Major Science and Technology Projects in Gansu Province(22ZD6GA003)the CAS“Light of West China”Program and West Light Foundation of The Chinese Academy of Sciences(xbzg-zdsys-202209).
文摘Herein,we demonstrated the integration of BiVO_(4)-based photoanode with metallic Zn cathode for high-performance CO_(2)reduction,and a record CO production rate of 113.32μmol cm^(−2)h^(−1)with a FECO of 90.57%has been achieved under simulated sunlight(AM 1.5 G,100 mW),accompanying with an excellent stability.More importantly,the direct observation of spatial charge separation/transfer and dynamic surface catalysis for both H_(2)O oxidation and CO_(2)reduction has been firstly achieved by the combination of in situ X-ray photoelectron spectroscopy(IS-XPS)with Fourier transform infrared reflection(IS-FTIR).Under light irradiation,the electron-hole pairs have been generated on BiVO_(4) photoanode,and holes rapidly transfer to photoanode surfaces for participating in oxygen evolution reaction(OER)through the formation of*OH and*OOH intermediates.Simultaneously,the proton-coupled electron transfer to the Zn cathode surfaces drive the reduction of adsorbed CO_(2)molecules into CO via the formation*COOH and*CO intermediates.Thereby,this work offers new insights into fundamental understanding of CO_(2)reduction process,which facilitates the future development of highly efficient carbon fixation systems.
基金supported by the Russian Science Foundation(No.22-13-00035)the National Outstanding Young Scientists Fund(No.52125002)+14 种基金the National Key Research and Development Program of China(Nos.2023YFC3904800 and 2022YFB4002501)the National Natural Science Foundation of China(Nos.52400228,52300139,22308063,52103340,U22A20418,22578302,52202208,52400163,52205054,22075171,52177214,22405201,52371072,52171078,52377218)the Key Research and Development Project of Science and Technology Department of Zhejiang Province(No.2024C03284(SD2))the Research Development Fund of Zhejiang A&F University(No.2024LFR042)the President Research Funds from Xiamen University(No.ZK1111)Nanqiang Youth Scholar program of Xiamen University,the Young Elite Scientists Sponsorship Program by CAST(No.2023QNRC001)Natural Science Foundation of Xiamen(No.3502z202471037)Open Fund of the State Environmental Protection Key Laboratory of Urban Air Particulate Matter Pollution Prevention and Control,College of Environmental Science and Engineering,Nankai University(No.NKPMLF202409)the Key Project of Research and Development Plan of Jiangxi Province(No.20243BBI91001)Natural Science Foundation of Shanghai(No.23ZR1423400)the Postdoctoral Science Research Program of Shaanxi(No.2023BSHEDzZ159)Xidian University Specially Funded Project for Interdisciplinary Exploration(No.TZJH2024062)the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd.(No.YPML-20240502058)the Fundamental Research Program of Shanxi Province(No.202303021212159)the Natural Science Foundation of Shanxi Normal University(No.JCYJ2024017).
文摘Sustainable development for our life is important task,which is driven by key materials and technologies.In this roadmap,we discuss three main aspects in addressing environmental questions,green chemical processes and energy challenges.They are included,such as gas treatment and separation,wastewater treatment,waste gas treatment,solid waste treatment,lithium extraction,hydrogen production,water splitting,CO_(2) reduction,photocatalytic clean technologies,plastic degradation,fuel cells,lithium batteries,sodium batteries,aqueous batteries,solid state batteries,metal air batteries and supercapacitors.Their status,challenges,progress and future perspectives are also discussed.We hope that this paper can give clear views on sustainable development in materials and technologies.
基金supported by the National Science Fund for Distinguished Young Scholars(21925603)the National Natural Science Foundation of China(22306185)the China Postdoctoral Science Foundation(2023M732032)。
文摘Conventional electrolytic methods for separating chemically similar lanthanides(Ln)and actinides(An)are limited by thermodynamics and slow reaction kinetics,restricting their efficiency in rare-earth refining and nuclear fuel recycling.Herein,we report an electroextraction and oxidative back-extraction(EOB)strategy utilizing a LiCl-KCl-KAlCl_(4) molten salt that overcomes these limitations by leveraging divergent interfacial reactivity.The EOB process achieves an exceptional separation factor for Ln/An(>1000),while simultaneously increasing the separation rate by at least one order of magnitude.Through in-situ synchrotron radiation X-ray micro-computed tomography(SR-μCT)and X-ray diffraction(SR-XRD),we capture selective oxidation-induced destabilization of Ln-Al alloys while actinides retain phase stability-directly visualizing the electrochemical alloy transition mechanism.This research redefines the separation of f-block elements in molten salt systems and introduces a multimodal approach to investigating transient interfacial phenomena that are usually inaccessible to conventional metallurgical diagnostics under extreme conditions.
基金financially supported by the National Natural Science Foundation of China(No.52303063)Hubei Provincial Department of Education Guided Scientific Research Project(No.B2024056)。
文摘Airless tires are essential for enhancing the safety,reliability,and convenience of maintenance of electric bicycles.Polyurethane(PU)is considered a promising candidate for such applications owing to its versatile properties.However,their use is limited by insufficient heat resistance and excessive dynamic heat generation under cyclic loading.In this study,star-shaped trifunctional polypropylene glycerol(PPG3)was incorporated into conventional poly(tetramethylene glycol)(PTMG)and 4,4'-methylenediphenyl diisocyanate(MDI)-based systems to construct microporous star-shaped casting polyurethanes(SCPU),with water serving as a green foaming agent.Unlike conventional small-molecule trifunctional crosslinkers that create junctions within hard segment domains,PPG3 introduces long flexible arms between the hard segments,anchoring the crosslinking points at its molecular core.The large steric hindrance of PPG3 effectively suppresses soft segment crystallization and lowers the degree of microphase separation,whereas the crosslinked network restricts chain mobility,thereby reducing dynamic heat generation.These structural features also enhance the heat resistance,yielding a softening temperature of 183℃,which is 30.9%higher than that of polyurethane without PPG3.When applied to airless tires by casting SCPU into rubber treads,the fabricated hybrid airless tires achieved a rolling distance of over 3000 km under a load of 65 kg at 25km/h without structural failure,satisfying practical performance requirements.This strategy offers a simple,solvent-free,and environmentally friendly process,underscoring the potential of SCPU for scalable production of high-performance airless tires.
基金supported by the Fundamental Research Funds for the Central Universities(No.2025JC008)the National Natural Science Foundation of China(grant number 52176105)+2 种基金the Science and Technology Project of Hebei Education Department-China(BJK2022063)the Hebei Natural Science Foundation-China(grant number E2025502038)the Funding Program for Cultivating Innovative Abilities of Graduate Students in Hebei Province of China(CXZZBS2025184).
文摘Biochar has been widely recognized as a promising solid CO_(2)adsorbent with economic and ecological benefits.Industrial CO_(2)emissions originate from diverse sources,while the pore structure and chemical functional groups of biochar exhibit varying degrees of influence on CO_(2)adsorption and separation performance under different adsorption conditions.Therefore,exploring the matching relationship between the physicochemical properties of biochar and its adsorption and separation performance at different adsorption conditions is essential for the development and optimization of carbon-based adsorbents.This study selected the high-performance extreme gradient boosting(XGB)algorithm from various algorithms and utilized it to develop CO_(2),N_(2),CH_(4)adsorption prediction models.Based on this,coupled prediction models were developed for CO_(2)/N_(2)and CO_(2)/CH_(4)adsorption selectivity.Furthermore,feature importance and partial dependence analysis were performed using SHAP values.The results indicate that during CO_(2)adsorption,the influence of the pore structure of biochar outweighs that of its chemical composition.Specifically,the pore structure of 0.4–0.6 nm is the most important property influencing CO_(2)adsorption at low and medium pressure(0–0.6 bar),and the pore structure of 0.6–0.8 nm,as well as the specific surface area contribute the most at high pressure(0.6–1 bar).During CO_(2)selective separation,the CO_(2)/N_(2)mixture is primarily separated through the selective adsorption of CO_(2)by nitrogen functional groups.In contrast,for CO_(2)/CH_(4)mixtures,pore structure<1 nm plays a more critical role in determining adsorption selectivity.In addition,molecular simulation studies further revealed the adsorption filling mechanisms of CO_(2)molecules within different pore sizes and functional groups.Finally,nitrogen-doped biochar was synthesized using de-alkalize lignin as the precursor,KOH as the activating agent,and urea as the nitrogen dopant.CO_(2),N_(2),and CH_(4)isothermal adsorption experiments were conducted,and the experimental results confirmed that the developed prediction models exhibit high accuracy(R^(2)>0.9).
文摘Recently,the Standardization Administration of China issued Announcement No.1 of 2026,officially approving the establishment of the Subcommittee 1 on Nonwoven Material of National Technical Committee 606 on Technical Textiles of Standardization Administration of China(SAC/TC606/SC1)and the Subcommittee 2 on Filtration and Separation Textiles of National Technical Committee 606 on Technical Textiles of Standardization Administration of China(SAC/TC606/SC2).The formation of these two subcommittees marks a crucial step in the standardization development of China's industrial textiles sector in specialized fields.
文摘Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or attitude instability,seriously compromising mission reliability.To address this engineering challenge,this paper proposes a multi-point low-impact locking/release mechanism based on the mobility model and energy conversion strategy.Through establishing a DOF constraint framework system,this paper systematically analyzes the energy transfer and conversion characteristics during the wing separation process,reveals the generation mechanism of impact loads,and conducts research on low-impact design based on energy conversion strategy.Building on this foundation,a single-point locking/release mechanism employing parallel trapezoidal key shaft structure was designed,which increases frictional contact time and reduces the energy release rate,thereby achieving low-impact characteristics.The mechanism's performance was validated through physical prototype development and systematic functional testing(including unlocking force,synchronization,and impact tests).Experimental results demonstrate:(1)Under 14 kN preload condition,the maximum unlocking force was only 92.54 N,showing a linear relationship with preload that satisfies the"strong-connection/weak-unlock"design requirement;(2)Wing separation was completed within 46 ms,with synchronization time difference among three separation mechanisms stably controlled within 12-14 ms,proving rapid and reliable operation;(3)The unlocking impact acceleration ranged between 26 and 73 g,below the 100 g design limit,confirming the effectiveness of the energy conversion strategy.The proposed low-impact locking/release mechanism design method based on energy conversion strategy resolves the traditional challenges of high impact and synchronization deficiencies.The synergistic optimization mechanism of"structural load reduction and performance improvement"provides a highly reliable technical solution for wing separable mechanisms while offering novel design insights for wing connection/separation systems engineering.
基金supported by the National Natural Science Foundation of China (Nos.22064020,22364022,and 22174125)the Applied Basic Research Foundation of Yunnan Province (Nos.202101AT070101 and 202201AT070029)。
文摘Developing a chiral material as versatile and universal chiral stationary phase(CSP) for chiral separation in diverse chromatographic techniques simultaneously is of great significance.In this study,we demonstrated for the first time that a chiral metal-organic cage(MOC),[Zn_(6)M_(4)],as a universal chiral recognition material for both multi-mode high-performance liquid chromatography(HPLC) and capillary gas chromatography(GC) enantioseparation.Two novel HPLC CSPs with different bonding arms(CSP-A with a cationic imidazolium bonding arm and CSP-B with an alkyl chain bonding arm) were prepared by clicking of functionalized chiral MOC [Zn_(6)M_(4)] onto thiolated silica via thiol-ene click chemistry.Meanwhile,a capillary GC column statically coated with the chiral MOC [Zn_(6)M_(4)] was also fabricated.The results showed that the chiral MOC exhibits excellent enantioselectivity not only in normal phase HPLC(NP-HPLC) and reversed phase(RP-HPLC) but also in GC,and various racemates were well separated,including alcohols,diols,esters,ketones,ethers,amines,and epoxides.Importantly,CSP-A and CSP-B are complementary to commercially available Chiralcel OD-H and Chiralpak AD-H columns in enantioseparation,which can separate some racemates that could not be or could not well be separated by the two widely used commercial columns,suggesting the great potential of the two prepared CSPs in enantioseparation.This work reveals that the chiral MOC is potential versatile chiral recognition materials for both HPLC and GC,and also paves the way to expand the potential applications of MOCs.
文摘Objective:To analyze the impact of maternal-infant separation on the physical and mental state of high-risk pregnancy patients and explore the clinical efficacy of targeted nursing interventions.Methods:A total of 80 high-risk pregnancy patients treated in our hospital from January 2023 to January 2024 were selected as the study subjects.These patients were randomly divided into an observation group and a control group(40 cases each)using a random number table.The control group received routine high-risk pregnancy nursing care,while the observation group received specialized maternal-infant separation nursing interventions in addition to routine care.The psychological and physiological states and nursing satisfaction of the two groups were compared before and after the intervention.Results:The SAS scores,SDS scores,and sleep quality scores of the observation group were significantly lower than those of the control group,with statistically significant differences(p<0.05).The incidence of postpartum hemorrhage in the observation group was significantly lower than that in the control group,and the initiation time of lactation was significantly earlier than that in the control group,with both differences being statistically significant(p<0.05).The nursing satisfaction of the observation group was significantly higher than that of the control group(80%vs.32/40),with a statistically significant difference(p<0.05).Conclusion:Maternal-infant separation exacerbates anxiety and depression in high-risk pregnancy patients,reduces sleep quality,increases the risk of postpartum hemorrhage,and delays the initiation of lactation.Specialized nursing interventions for maternal-infant separation can improve the physical and mental state of high-risk pregnancy patients,reduce the incidence of postpartum complications,and enhance nursing satisfaction,making them worthy of clinical application and promotion.
基金the support of the Major Science and Technology Project of Yunnan Province,China(Grant No.202502AD080007)the National Natural Science Foundation of China(Grant No.52378288)。
文摘Vehicle-induced response separation is a crucial issue in structural health monitoring(SHM).This paper proposes a block-wise sliding recursive wavelet transform algorithm to meet the real-time processing requirements of monitoring data.To extend the separation target from a fixed dataset to a continuously updating data stream,a block-wise sliding framework is first developed.This framework is further optimized considering the characteristics of real-time data streams,and its advantage in computational efficiency is theoretically demonstrated.During the decomposition and reconstruction processes,information from neighboring data blocks is fully utilized to reduce algorithmic complexity.In addition,a delay-setting strategy is introduced for each processing window to mitigate boundary effects,thereby balancing accuracy and efficiency.Simulated signal experiments are conducted to determine the optimal delay configuration and to verify the algorithm’s superior performance,achieving a lower Root Mean Square Error(RMSE)and only 0.0249 times the average computational time compared with the original algorithm.Furthermore,strain signals from the Lieshi River Bridge are employed to validate the method.The proposed algorithm successfully separates the static trend from vehicle-induced responses in real time across different sampling frequencies,demonstrating its effectiveness and applicability in real-time bridge monitoring.
基金the National Natural Science Foundation of China(Grant Nos.42274003,41974007,and 41774019).
文摘The GRACE(Gravity Recovery and Climate Experiment)space mission recorded temporal variation characteristics of the global gravity field at decadal timescales.The gravity data have been shown to capture the dynamics of flows within the outer core and their effects on the core-mantle boundary.We first aim to remove global surface process gravity signals from the GRACE data.We then construct the global core magnetic field according to the CHAOS-7 model.Finally,we apply the blind source separation method to decompose the processed gravity signals and core magnetic signals and compute the power spectral density of the gravity and magnetic field signals by using the Lomb-Scargle periodogram approach.We have discovered a signal cycle(of~6 years)in the principal components of the core magnetic and gravity signals,potentially as a result of deep Earth processes.The main principal components of the core magnetic and gravity signals reveal that the variation trends in the second-order time derivative of the core magnetic field are similar to those in the gravity field.After 2014,the second-order time derivative of the core magnetic field exhibited linear and rapid change characteristics,which were the same as the change in the gravity field and are consistent with existing research results.
基金financial support from the National Natural Science Foundation of China (22338011, 22378299)Hainan Province Science and Technology Special Fund (ZDYF2025SHFZ025)+1 种基金Ningbo Key Research and Development Project (2022Z121)the China Postdoctoral Science Foundation (2025M771194)。
文摘Due to complex ion-ion and ion-membrane interactions, creating innovative membrane structures to acquire favorable ion mixing effect and high separation performance remains a big challenge. Herein, we design covalent organic framework(COF) scaffold membrane with gate-lane nanostructure for efficient Li^(+)/Mg^(2+) separation. COF nanosheets, serving as the scaffold, are intercalated by polyethyleneimine(PEI) to form the permeating layer. Subsequently, PEI on the surface reacts with 1,4-phenylene diisocyanate to form the polyurea gating layer. The gating layer, bearing tailored smaller pore size,affords high rejection to co-ions(Mg^(2+)) and thus high Li^(+)/Mg^(2+) selectivity. The permeating layer, with asymmetric charge and spatial nanostructure for creating individual lanes of Li^(+) and Cl~-, facilitates Li^(+) transport and thus high Li^(+) permeability. The optimum COF scaffold membrane exhibits the permeance of 11.5 L m^(-2) h^(-1)/bar^(-1) and true selectivity of 231.9 with Li^(+) enrichment of 120.2% at the Mg^(2+)/Li^(+) mass ratio of 50, exceeding the ideal selectivity of 80.5 and outperforming all ever-reported positively charged nanofiltration membranes. Our work may stimulate the further thinking about how to design the hierarchical membrane structure to achieve favorable ion mixing effect and break the membrane permeability-selectivity trade-off in chemical separations.
基金supported by the National Natural Science Foundation of China(Grant Nos.12534013,12047561,and 12104507)the Science and Technology Innovation Program of Hunan Province(Grant Nos.2025ZYJ001 and 2021RC4026)the National University of Defense Technology Research Fund Project.
文摘The accumulation and circulation of carbon and hydrogen contribute to the chemical evolution of ice giant planets.Species separation and diamond precipitation have been reported in carbon-hydrogen systems and have been verified by static and shock compression experiments.Nevertheless,the dynamic formation processes underlying these phenomena remain insufficiently understood.In combination with a deep learning model,we demonstrate that diamonds form through a three-step process involving dissociation,species separation,and nucleation processes.Under shock conditions of 125 GPa and 4590 K,hydrocarbons decompose to give hydrogen and low-molecular-weight alkanes(CH_(4) and C_(2)H_(6)),which escape from the carbon chains,resulting in C/H species separation.The remaining carbon atoms without C-H bonds accumulate and nucleate to form diamond crystals.The process of diamond growth is associated with a critical nucleus size at which the dynamic energy barrier plays a key role.These dynamic processes of diamond formation provide insight into the establishment of a model for the evolution of ice giant planets.
