Hydrogels,owing to their porous network structure resembling the extracellular matrix(ECM),have become essential scaffold materials in the field of cartilage tissue engineering.Among them,gelatin methacrylate(GelMA)hy...Hydrogels,owing to their porous network structure resembling the extracellular matrix(ECM),have become essential scaffold materials in the field of cartilage tissue engineering.Among them,gelatin methacrylate(GelMA)hydrogels are widely used in bioink development due to their excellent biocompatibility,biodegradability,and tunable photo-crosslinking properties.However,the high biocompatibility of pure GelMA often comes at the cost of mechanical strength,limiting its applicability in cartilage regeneration.To overcome this trade-off,this study developed composite bioinks based on GelMA,silk fibroin(SF),and polyethylene oxide(PEO)for fabricating porous hydrogel scaffolds,which were then systematically characterized in terms of morphology,porosity,hydrophilicity,mechanical strength,rheological behavior,printability,and cytocompatibility.In this design,PEO serves as a porogen to generate highly porous structures(porosity up to 88%),while SF compensates for the mechanical loss caused by PEO,enabling the scaffold to retain a compression strength of up to 29.10 kPa.Among the tested formulations,the 10%GelMA/1%SF/1.5%PEO(1%=0.01 g/mL)bioink exhibited excellent printability,mechanical integrity,and cytocompatibility,and it supported a robust deposition of collagenⅡand aggrecan by chondrocytes after printing.This work provides a versatile strategy for balancing the biocompatibility and mechanical robustness in bioinks,offering a promising platform for next-generation cartilage tissue engineering scaffolds.展开更多
In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrabilit...In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables.展开更多
Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current method...Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current methods,however,are complicated and time-consuming,the mass production remains a chal-lenge.Herein,we proposed a new high-efficiency strategy for synthesis of MMB_(2)using molten aluminum as the medium for the first time.The prepared Al-containing multi-component borides(TiZrHfNbTa)B_(2)microcrystals had a homogeneous composition with a hexagonal AlB_(2)structure and ultra-high hardness value of∼35.3 GPa,which was much higher than data reported in the literature and the rule of mix-ture estimations.Furthermore,combined with the First-principles calculation results,we found that the Poisson’s ratio(v)values exhibit a clearly ascending trend from 0.17 at VEC=3.5 to 0.18 at VEC=3.4,then to 0.201 at VEC=3.2 with the increasing of Al content.This indicates that the intrinsic toughness of multi-component boride microcrystals is obviously enhanced by the trace-doped Al elements.Besides,the fabricated Al-containing multi-component boride microcrystals have superior oxidation activation en-ergy and structural stability.The enhanced oxidation resistance is mainly attributed to the formation of a protective Al2 O3 oxide layer and the lattice distortion,both of which lead to sluggish diffusion of O_(2).These findings propose a new unexplored avenue for the fabrication of MMB_(2)materials with supe-rior comprehensive performance including ultra-hardness and intrinsically improved thermo-mechanical properties.展开更多
The phase transition among different solid forms of active pharmaceutical ingredients can significantly influence their physicochemical properties,potentially leading to clinical safety risks.However,phase transition ...The phase transition among different solid forms of active pharmaceutical ingredients can significantly influence their physicochemical properties,potentially leading to clinical safety risks.However,phase transition mechanisms remain under explored,especially in multi-component drugs.Here we report a novel ciprofloxacin-diclofenac salt system and investigate phase transitions among its anhydrate,dihydrate,and methanol solvate forms.The study focused on the influence of water activity and solvent vapor conditions,elucidating the role of vip molecules in driving these transitions.These findings offer new insights into polymorphic phase transitions,advancing our understanding of stability and performance in pharmaceutical formulations.展开更多
The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ...The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ceramics were prepared by spark plasma sintering.Compulsorily,all the multi-component carbide samples have similar carbon content,grain size,and uniform compositional distribution by optimizing the sintering process and adjusting the initial raw materials.Hence the interference of other factors on the hardness of multi-component carbide ceramics is minimized.The effects of changes in the elemental species on the lattice distortion,bond strength,bonding properties,and electronic structure of multi-component carbide ceramics were thoroughly analyzed.These results show that the hardening of multi-component carbide ceramic can be attributed to the coupling of solid solution strengthening caused by lattice distortion and covalent bond strengthening.Besides,the“host lattice”of multi-component carbide ceramics is defined based on the concept of supporting lattice.The present work is of great significance for a deeper understanding of the hardening mechanism of multi-component carbide ceramics and the design of superhard multi-component carbides.展开更多
A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficie...A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficiently obtained in moderate to good yields at room temperature.This metal-free visiblelight-driven tandem reaction was conducted through proton-coupled electron transfer(PCET)process using water as the hydrogen donor and 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene(4CzIPN)as the photocatalyst.展开更多
The construction of a borehole correction library for the multi-component array induction tool in deviated boreholes involves extensive 3D forward modeling and typically requires significant computational resources.To...The construction of a borehole correction library for the multi-component array induction tool in deviated boreholes involves extensive 3D forward modeling and typically requires significant computational resources.To address this challenge,this paper proposes an efficient algorithm for the library construction based on the 3D finite volume method(FVM)and contraction high-order Born approximation(CHBA).First,the electromagnetic(EM)field solution region is divided into two symmetric subregions based on the symmetry of the correction library model and the EM field.Numerical solution on a single subregion,combined with the symmetry boundary extension technique,enhances the efficiency of the 3D numerical simulation.Second,three reference mud conductivities are selected based on the mud conductivity range,and the CHBA is applied to calculate the EM responses at all mud conductivity nodes rapidly.Third,the number of forward simulation operations is further reduced by exploiting the principle that models with different frequencies and different formation conductivities have equivalent EM responses.Numerical experiments demonstrate the correctness and feasibility of the proposed algorithm.Compared to conventional 3D modeling,the proposed algorithm achieves approximately a 20-fold speedup in library construction,effectively reducing computational resources and time consumption.展开更多
Green solvent pretreatment of biomass represents a promising ap-proach for enhancing the econom-ic value of lignocellulosic deriva-tives.In this study,corncob biomass was treated with a diol-based deep eutectic solven...Green solvent pretreatment of biomass represents a promising ap-proach for enhancing the econom-ic value of lignocellulosic deriva-tives.In this study,corncob biomass was treated with a diol-based deep eutectic solvent(DES)under mild conditions,facilitating efficient cellulose separation.The extracted cellulose was subsequently used to fabricate cellulose hydrogels in an aqueous zinc chloride solution.The resulting hydrogel exhibited a“water-in-salt”effect due to the high concentration of ZnCl_(2).Leveraging the antifreeze properties of sorbitol,the system demon-strated outstanding low-temperature electrochemical performance,including a broad operat-ing voltage window and an ionic conductivity of 38.4 mS·cm^(-1)at-20℃.At 20℃,the de-vice achieved an energy density of 206 Wh·kg^(-1)and a power density of 2701.05 W·kg^(-1)at a current density of 1 A·g^(-1).Moreover,the flexible zinc-ion hybrid supercapacitor(ZHSC)maintained 89%of its capacitance and nearly 100%Coulombic efficiency after 5500 cycles at 20℃.This work not only advances the development of zinc-ion energy storage devices but al-so establishes a new paradigm for the green and direct utilization of biomass-derived materi-als.展开更多
While nuclear energy represents a low-carbon and high-efficiency energy source that plays a vital role in the global energy mix,the limitations of spent fuel reprocessing technology pose a major challenge to its susta...While nuclear energy represents a low-carbon and high-efficiency energy source that plays a vital role in the global energy mix,the limitations of spent fuel reprocessing technology pose a major challenge to its sustainable development.The PUREX(plutonium uranium redox extraction)process is currently the dominant nuclear fuel reprocessing technology in the world.However,the key extractant in this process is tributyl phosphate(TBP),which degrades under intense radiation,high temperatures,and strong acidity.This leads to the production of dibutyl phosphate,monobutyl phosphate,and other degradation byproducts,which may reduce the extraction efficiency and trigger third-phase formation and equipment corrosion.This paper systematically reviews the degradation mechanisms of TBP and its diluents,the analytical technique suitable for characterizing degradation products,and the impact of degradation products on the post-treatment process.Additionally,optimization strategies employed for suppressing third-phase formation are discussed.This study offers a theoretical foundation and technical insights in optimizing the PUREX process and ensuring the safe operation of the post-treatment process.展开更多
Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via lo...Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions.展开更多
Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through...Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through covalent bonds exhibits excellent structural stability.It has been shown that the stationary phases prepared by combining MOF and COF can make up for the poor stability of MOF@SiO_(2),and the MOF/COF composites have superior chromatographic separation performance.However,the traditional methods for preparing COF/MOF based stationary phases are generally solvent thermal synthesis.In this study,a green and low-cost synthesis method was proposed for the preparation of MOF/COF@SiO_(2) stationary phase.Firstly,COF@SiO_(2) was prepared in a choline chloride/ethylene glycol based deep eutectic solvent(DES).Secondly,another acid-base tunable DES prepared by mixing p-toluenesulfonic acid(PTSA)and 2-methylimidazole in different proportions was introduced as the reaction solvent and reactant for rapid synthesis of MOF/COF@SiO_(2).Compared with the toxic transition metal-based MOFs selected in most previous studies,a lightweight and non-toxic S-zone metal(calcium) based MOF was employed in this study.PTSA and calcium will form the calcium/oxygen-containing organic acid framework in acidic DES,which assembles with terephthalic acid dissolved in basic DES to form MOF.The strong hydrogen bonding effect of DES can facilitate rapid assembly of Ca-MOF.The obtained Ca-MOF/COF@SiO_(2) can be used for multi-mode chromatography to efficiently separate multiple isomeric/hydrophilic/hydrophobic analytes.The synthesis method of Ca-MOF/COF@SiO_(2) is green and mild,especially the use of acid-base tunable DES promotes the rapid synthesis of non-toxic Ca-MOF/COF@silica composites,which offers an innovative approach of greenly synthesizing novel MOF/COF stationary phases and extends their applications in the field of chromatography.展开更多
A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance ti...A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance time can be shared by more than one component, and the system availability can be improved. Then, the generation characteristics of the random failure time are researched based on the replacement maintenance and the minima[ maintenance. Furthermore, by choosing the opportunistic replacement ages of each component as opti- mized variables, a simulation algorithm based on an opportunistic maintenance policy is designed to maximize the total availability. Finally, the simulation result shows the validity of the algorithm by an example.展开更多
This review focuses on the recent research progress in the multi-component assembly of luminescent rare earth hybrid materials, which is based on the luminescent rare earth compounds and two or more other building uni...This review focuses on the recent research progress in the multi-component assembly of luminescent rare earth hybrid materials, which is based on the luminescent rare earth compounds and two or more other building units, including the other photoactive species. It covers the multi-component luminescent rare earth hybrids which was assembled with different(a) organic-inorganic polymeric units,(b)nanoporous units,(c) nanoparticle composites or(d) other developing special units. Finally, future challenges and opportunities in this field are discussed. Herein it mainly focuses on the work of Yan's group in recent years.展开更多
A general scheme for generating a multi-component integrable equation hierarchy is proposed. A simple 3M- dimensional loop algebra ~X is produced. By taking advantage of ~X a new isospectral problem is established and...A general scheme for generating a multi-component integrable equation hierarchy is proposed. A simple 3M- dimensional loop algebra ~X is produced. By taking advantage of ~X a new isospectral problem is established and then by making use of the Tu scheme the multi-component Dirac equation hierarchy is obtained. Finally, an expanding loop algebra ~FM of the loop algebra ~X is presented. Based on the ~FM, the multi-component integrable coupling system of the multi-component Dirac equation hierarchy is investigated. The method in this paper can be applied to other nonlinear evolution equation hierarchies.展开更多
Seismic AVO analysis now is one of the major criteria for recognizing potential hydrocarbon reservoirs. Volume scattering information that carries information of stratigraphic structure, lithology, and pore fluid is m...Seismic AVO analysis now is one of the major criteria for recognizing potential hydrocarbon reservoirs. Volume scattering information that carries information of stratigraphic structure, lithology, and pore fluid is more useful for seismic exploration. However, traditional AVO analysis is based on the Zoeppritz equation, which only contains single-interface information. Quantitative interpretation of the thin bed thickness is essential to thin bed structure interpretation, reservoir description, and lateral reservoir prediction. The reflectance spectrum equation based on the elastic wave propagation matrix in the frequency domain derived in this paper shows that both interfaces and intervals have an effect on amplitude. The equation includes information about both single interfaces and volume scattering. Since the reflectance spectrum equation is a continuous function of thin bed thickness and frequency, it is convenient to analyze the effects of a single frequency and bed thickness on the reflectance spectrum. Bed thickness is analyzable until the bed thickness is vanishingly small. These characteristics can＇t be achieved by Fourier transform. The propagation of seismic waves is complex and various wave modes exist simultaneously. The reflectance spectrum includes various propagating wave modes and multiples and is better for simulating multi-component thin bed AVO responses than the ray tracing method.展开更多
The conventional digital core models are usually small in size and have difficulty in representing the complex structures of heterogeneous rocks;Therefore,the parameters of simulated rock physics are difficult to be r...The conventional digital core models are usually small in size and have difficulty in representing the complex structures of heterogeneous rocks;Therefore,the parameters of simulated rock physics are difficult to be referenced.In this study,we propose a feasible simulation method for obtaining multi-scale and multi-component digital cores based on three types of sandstone samples.In the proposed method,the plug and subplug samples are scanned via micro-computed tomography at different resolutions.Furthermore,the images are precisely registered using the proposed hybrid image registration method.In case of high-resolution images,the traditional segmentation method is used to segment the cores into pores and minerals.Subsequently,we established the relations between the gray values and the porosity/mineral content in case of the low-resolution images based on the registered domains and the relation curves were applied to the segmentation of the low-resolution images.The core images constitute the multi-scale and multi-component digital core models after segmentation.Further,the elastic properties of the three samples were simulated at both fine and coarse scales based on the multi-scale and multi-component digital core models,and four component models were considered.The results show that the multi-scale and multi-component digital core models can overcome the representative limits of the conventional digital core models and accurately characterize pores and minerals at different scales.The numerical results of the elastic modulus are more representative at large scales,and considerably reliable results can be obtained by appropriately considering the minerals.展开更多
The influence of melt superheating treatment on the solid/liquid （S/L） interface morphology of directionally solidified Ni-based superalloy DZ125 is investigated to elucidate the relationship between melt characteri...The influence of melt superheating treatment on the solid/liquid （S/L） interface morphology of directionally solidified Ni-based superalloy DZ125 is investigated to elucidate the relationship between melt characteristic and S/L interface stability. The results indicate that the interface morphology is not only related to the withdrawal velocity （R） but also to the melt superheating temperature （Ts） when the thermal gradient of solidification interface remains constant for different Ts with appropriate superheating treatment regulation. The interface morphology changes from cell to plane at R of 1.1 μm/s when Ts increases from 1500°C to 1650°C, and maintains plane with further elevated Ts of 1750°C. However, the interface morphology changes from coarse dendrite to cell and then to cellular dendrite at R of 2.25 μm/s when Ts increases from 1500°C to 1650°C and then to 1750°C. It is proved that the solidification onset temperature and the solidification interval undergo the nonlinear variation when Ts increases from 1500°C to 1680°C, and the turning point is 1650°C at which the solidification onset temperature and the solidification interval are all minimum. This indicates that the melt superheating treatment enhances the solidification interface stability and has important effect on the solidification characteristics.展开更多
Aiming at wind turbines,the opportunistic maintenance optimization is carried out for multi-component system,where minimal repair,imperfect repair,replacement as well as their effects on component’s effective age are...Aiming at wind turbines,the opportunistic maintenance optimization is carried out for multi-component system,where minimal repair,imperfect repair,replacement as well as their effects on component’s effective age are considered.At each inspection point,appropriate maintenance mode is selected according to the component’s effective age and its maintenance threshold.To utilize the maintenance opportunities for the components among the wind turbines,opportunistic maintenance approach is adopted.Meanwhile,the influence of seasonal factor on the component’s failure rate and improvement factor’s decrease with the increase of repair’s times are also taken into account.The maintenance threshold is set as the decision variable,and an opportunistic maintenance optimization model is proposed to minimize wind turbine’s life-cycle maintenance cost.Moreover,genetic algorithm is adopted to solve the model,and the effectiveness is verified with a case study.The results show that based on the component’s inherent reliability and maintainability,the proposed model can provide optimal maintenance plans accordingly.Furthermore,the higher the component’s reliability and maintainability are,the less the times of repair and replacement will be.展开更多
To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainabili...To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainability was analyzed, and the layout problem for maintainability was presented. It was formulated as an optimization problem, where maintainability, layout space and distance requirement were formulated as objective functions. A multi-objective particle swarm optimization algorithm, in which the constrained-domination relationship and the update strategy of the global best were simply modified, was then used to obtain Pareto optimal solutions for the maintainability layout design problem. Finally, application in oxygen generation system of a spacecraft was studied in detail to illustrate the effectiveness and usefulness of the proposed method. The results show that the concurrent maintainability design can be carried out during the layout design process by solving the layout optimization problem for maintainability.展开更多
In the present study, a method for the quantitative analysis of multi-components by single marker(QAMS) has been developed and validated for the simultaneous determination of echinacoside(ECH), tubuloside A, acteoside...In the present study, a method for the quantitative analysis of multi-components by single marker(QAMS) has been developed and validated for the simultaneous determination of echinacoside(ECH), tubuloside A, acteoside, isoacteoside, and2’-acetylacteoside in Cistanches Herba. ECH was used as the internal standard(IS) to obtain the relative correction factors(RCFs) of the other four phenylethanoid glycosides(PhGs);meanwhile, various influencing factors on RCFs were investigated under different conditions. The content of each component was calculated with RCF. The results were compared with those obtained by the external standard method(ESM) to verify the feasibility and accuracy of the established QAMS method. No significant difference was found in the quantitative results of 10 batches of Cistanches Herba between QAMS and ESM. The proposed QAMS method for simultaneous determination of PhGs in Cistanches Herba is accurate and feasible, providing an efficient and economical approach for the quality control of Cistanches Herba.展开更多
基金supported by the Project(No.JCKY2024408C010)the Shanxi Province Key Research and Development Project(No.202302130501006)+4 种基金the National Natural Science Foundation of China(Nos.82403350,51975400,62031022)the Shanxi Provincial Key Medical Scientific Research Project(No.2020XM06)the Shanxi Provincial Basic Research Project(No.202103021223040)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(No.2021L044)the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(No.2022SX-TD026),China.
文摘Hydrogels,owing to their porous network structure resembling the extracellular matrix(ECM),have become essential scaffold materials in the field of cartilage tissue engineering.Among them,gelatin methacrylate(GelMA)hydrogels are widely used in bioink development due to their excellent biocompatibility,biodegradability,and tunable photo-crosslinking properties.However,the high biocompatibility of pure GelMA often comes at the cost of mechanical strength,limiting its applicability in cartilage regeneration.To overcome this trade-off,this study developed composite bioinks based on GelMA,silk fibroin(SF),and polyethylene oxide(PEO)for fabricating porous hydrogel scaffolds,which were then systematically characterized in terms of morphology,porosity,hydrophilicity,mechanical strength,rheological behavior,printability,and cytocompatibility.In this design,PEO serves as a porogen to generate highly porous structures(porosity up to 88%),while SF compensates for the mechanical loss caused by PEO,enabling the scaffold to retain a compression strength of up to 29.10 kPa.Among the tested formulations,the 10%GelMA/1%SF/1.5%PEO(1%=0.01 g/mL)bioink exhibited excellent printability,mechanical integrity,and cytocompatibility,and it supported a robust deposition of collagenⅡand aggrecan by chondrocytes after printing.This work provides a versatile strategy for balancing the biocompatibility and mechanical robustness in bioinks,offering a promising platform for next-generation cartilage tissue engineering scaffolds.
基金sponsored by the National Natural Science Foundations of China under Grant Nos.12301315,12235007,11975131the Zhejiang Provincial Natural Science Foundation of China under Grant No.LQ20A010009。
文摘In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables.
基金financially supported by the National Natural Science Foundation of China(Nos.52271033 and 52071179)the Key program of National Natural Science Foundation of China(No.51931003)+2 种基金Natural Science Foundation of Jiangsu Province,China(No.BK20221493)Jiangsu Province Leading Edge Technology Basic Research Major Project(No.BK20222014)Foundation of“Qinglan Project”for Colleges and Universities in Jiangsu Province.
文摘Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current methods,however,are complicated and time-consuming,the mass production remains a chal-lenge.Herein,we proposed a new high-efficiency strategy for synthesis of MMB_(2)using molten aluminum as the medium for the first time.The prepared Al-containing multi-component borides(TiZrHfNbTa)B_(2)microcrystals had a homogeneous composition with a hexagonal AlB_(2)structure and ultra-high hardness value of∼35.3 GPa,which was much higher than data reported in the literature and the rule of mix-ture estimations.Furthermore,combined with the First-principles calculation results,we found that the Poisson’s ratio(v)values exhibit a clearly ascending trend from 0.17 at VEC=3.5 to 0.18 at VEC=3.4,then to 0.201 at VEC=3.2 with the increasing of Al content.This indicates that the intrinsic toughness of multi-component boride microcrystals is obviously enhanced by the trace-doped Al elements.Besides,the fabricated Al-containing multi-component boride microcrystals have superior oxidation activation en-ergy and structural stability.The enhanced oxidation resistance is mainly attributed to the formation of a protective Al2 O3 oxide layer and the lattice distortion,both of which lead to sluggish diffusion of O_(2).These findings propose a new unexplored avenue for the fabrication of MMB_(2)materials with supe-rior comprehensive performance including ultra-hardness and intrinsically improved thermo-mechanical properties.
基金supported by the Young Scientists Promotion Fund of Natural Science Foundation of Guangdong Province(No.2023A1515030128)Natural Science Foundation of Guangdong Province(No.2024A1515011590)+1 种基金National Natural Science Foundation of China(No.81703438)CAMS Innovation Fund for Medical Sciences(No.2022-I2M-1-015).
文摘The phase transition among different solid forms of active pharmaceutical ingredients can significantly influence their physicochemical properties,potentially leading to clinical safety risks.However,phase transition mechanisms remain under explored,especially in multi-component drugs.Here we report a novel ciprofloxacin-diclofenac salt system and investigate phase transitions among its anhydrate,dihydrate,and methanol solvate forms.The study focused on the influence of water activity and solvent vapor conditions,elucidating the role of vip molecules in driving these transitions.These findings offer new insights into polymorphic phase transitions,advancing our understanding of stability and performance in pharmaceutical formulations.
基金financially supported by the National Natural Science Foundation of China(Nos.52032002,52372060,51972081,and U22A20128)the National Safety Academic Foundation(No.U2130103)+1 种基金the National Key Laboratory of Precision Hot Processing of Metals(No.61429092300305)Heilongjiang Touyan Team Program are gratefully acknowledged.
文摘The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ceramics were prepared by spark plasma sintering.Compulsorily,all the multi-component carbide samples have similar carbon content,grain size,and uniform compositional distribution by optimizing the sintering process and adjusting the initial raw materials.Hence the interference of other factors on the hardness of multi-component carbide ceramics is minimized.The effects of changes in the elemental species on the lattice distortion,bond strength,bonding properties,and electronic structure of multi-component carbide ceramics were thoroughly analyzed.These results show that the hardening of multi-component carbide ceramic can be attributed to the coupling of solid solution strengthening caused by lattice distortion and covalent bond strengthening.Besides,the“host lattice”of multi-component carbide ceramics is defined based on the concept of supporting lattice.The present work is of great significance for a deeper understanding of the hardening mechanism of multi-component carbide ceramics and the design of superhard multi-component carbides.
基金supported by Sichuan Science and Technology Program(No.2023NSFSC0101)the 2024 Provincial platform project of Chengdu Normal University(No.GNFZ202404)+1 种基金Natural Science Foundation of Shandong Province(No.ZR2021MB065)National Natural Science Foundation of China(No.22101237)。
文摘A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficiently obtained in moderate to good yields at room temperature.This metal-free visiblelight-driven tandem reaction was conducted through proton-coupled electron transfer(PCET)process using water as the hydrogen donor and 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene(4CzIPN)as the photocatalyst.
基金funded by the Forward-looking Basic Science and Technology Research Project of PetroChina Company Limited(2025DJ104)the National Natural Science Foundation of China(42174150)the National Science and Technology Major Project for Deep Earth Probe and Mineral Resources Exploration(2024ZD1003005).
文摘The construction of a borehole correction library for the multi-component array induction tool in deviated boreholes involves extensive 3D forward modeling and typically requires significant computational resources.To address this challenge,this paper proposes an efficient algorithm for the library construction based on the 3D finite volume method(FVM)and contraction high-order Born approximation(CHBA).First,the electromagnetic(EM)field solution region is divided into two symmetric subregions based on the symmetry of the correction library model and the EM field.Numerical solution on a single subregion,combined with the symmetry boundary extension technique,enhances the efficiency of the 3D numerical simulation.Second,three reference mud conductivities are selected based on the mud conductivity range,and the CHBA is applied to calculate the EM responses at all mud conductivity nodes rapidly.Third,the number of forward simulation operations is further reduced by exploiting the principle that models with different frequencies and different formation conductivities have equivalent EM responses.Numerical experiments demonstrate the correctness and feasibility of the proposed algorithm.Compared to conventional 3D modeling,the proposed algorithm achieves approximately a 20-fold speedup in library construction,effectively reducing computational resources and time consumption.
基金supported by the National Key R&D Program of China(No.2023YFA1507500)the Nation-al Natural Science Foundation of China(No.52373159)。
文摘Green solvent pretreatment of biomass represents a promising ap-proach for enhancing the econom-ic value of lignocellulosic deriva-tives.In this study,corncob biomass was treated with a diol-based deep eutectic solvent(DES)under mild conditions,facilitating efficient cellulose separation.The extracted cellulose was subsequently used to fabricate cellulose hydrogels in an aqueous zinc chloride solution.The resulting hydrogel exhibited a“water-in-salt”effect due to the high concentration of ZnCl_(2).Leveraging the antifreeze properties of sorbitol,the system demon-strated outstanding low-temperature electrochemical performance,including a broad operat-ing voltage window and an ionic conductivity of 38.4 mS·cm^(-1)at-20℃.At 20℃,the de-vice achieved an energy density of 206 Wh·kg^(-1)and a power density of 2701.05 W·kg^(-1)at a current density of 1 A·g^(-1).Moreover,the flexible zinc-ion hybrid supercapacitor(ZHSC)maintained 89%of its capacitance and nearly 100%Coulombic efficiency after 5500 cycles at 20℃.This work not only advances the development of zinc-ion energy storage devices but al-so establishes a new paradigm for the green and direct utilization of biomass-derived materi-als.
基金supported by the Youth Talent Project of China Nuclear Power Engineering Co.,Ltd.(KY24045).
文摘While nuclear energy represents a low-carbon and high-efficiency energy source that plays a vital role in the global energy mix,the limitations of spent fuel reprocessing technology pose a major challenge to its sustainable development.The PUREX(plutonium uranium redox extraction)process is currently the dominant nuclear fuel reprocessing technology in the world.However,the key extractant in this process is tributyl phosphate(TBP),which degrades under intense radiation,high temperatures,and strong acidity.This leads to the production of dibutyl phosphate,monobutyl phosphate,and other degradation byproducts,which may reduce the extraction efficiency and trigger third-phase formation and equipment corrosion.This paper systematically reviews the degradation mechanisms of TBP and its diluents,the analytical technique suitable for characterizing degradation products,and the impact of degradation products on the post-treatment process.Additionally,optimization strategies employed for suppressing third-phase formation are discussed.This study offers a theoretical foundation and technical insights in optimizing the PUREX process and ensuring the safe operation of the post-treatment process.
基金the National Nature Science Foundation of China for Excellent Young Scientists Fund(32222058)Fundamental Research Foundation of CAF(CAFYBB2022QB001).
文摘Developing biomass platform compounds into high value-added chemicals is a key step in renewable resource utilization.Herein,we report porous carbon-supported Ni-ZnO nanoparticles catalyst(Ni-ZnO/AC)synthesized via low-temperature coprecipitation,exhibiting excellent performance for the selective hydrogenation of 5-hydroxymethylfurfural(HMF).A linear correlation is first observed between solvent polarity(E_(T)(30))and product selectivity within both polar aprotic and protic solvent classes,suggesting that solvent properties play a vital role in directing reaction pathways.Among these,1,4-dioxane(aprotic)favors the formation of 2,5-bis(hydroxymethyl)furan(BHMF)with 97.5%selectivity,while isopropanol(iPrOH,protic)promotes 2,5-dimethylfuran production with up to 99.5%selectivity.Mechanistic investigations further reveal that beyond polarity,proton-donating ability is critical in facilitating hydrodeoxygenation.iPrOH enables a hydrogen shuttle mechanism where protons assist in hydroxyl group removal,lowering the activation barrier.In contrast,1,4-dioxane,lacking hydrogen bond donors,stabilizes BHMF and hinders further conversion.Density functional theory calculations confirm a lower activation energy in iPrOH(0.60 eV)compared to 1,4-dioxane(1.07 eV).This work offers mechanistic insights and a practical strategy for solvent-mediated control of product selectivity in biomass hydrogenation,highlighting the decisive role of solvent-catalyst-substrate interactions.
基金supported by National Natural Science Foundation of China (Nos.21906124,32302202)Natural Science Foundation of Hubei Province (No.2017CFB220)Natural Science Foundation of Shandong Province (No.ZR2023MH278)。
文摘Metal organic framework(MOF) assembled with coordination bonds has the disadvantage of poor stability that limits its application in the field of stationary phase,while covalent organic framework(COF)assembled through covalent bonds exhibits excellent structural stability.It has been shown that the stationary phases prepared by combining MOF and COF can make up for the poor stability of MOF@SiO_(2),and the MOF/COF composites have superior chromatographic separation performance.However,the traditional methods for preparing COF/MOF based stationary phases are generally solvent thermal synthesis.In this study,a green and low-cost synthesis method was proposed for the preparation of MOF/COF@SiO_(2) stationary phase.Firstly,COF@SiO_(2) was prepared in a choline chloride/ethylene glycol based deep eutectic solvent(DES).Secondly,another acid-base tunable DES prepared by mixing p-toluenesulfonic acid(PTSA)and 2-methylimidazole in different proportions was introduced as the reaction solvent and reactant for rapid synthesis of MOF/COF@SiO_(2).Compared with the toxic transition metal-based MOFs selected in most previous studies,a lightweight and non-toxic S-zone metal(calcium) based MOF was employed in this study.PTSA and calcium will form the calcium/oxygen-containing organic acid framework in acidic DES,which assembles with terephthalic acid dissolved in basic DES to form MOF.The strong hydrogen bonding effect of DES can facilitate rapid assembly of Ca-MOF.The obtained Ca-MOF/COF@SiO_(2) can be used for multi-mode chromatography to efficiently separate multiple isomeric/hydrophilic/hydrophobic analytes.The synthesis method of Ca-MOF/COF@SiO_(2) is green and mild,especially the use of acid-base tunable DES promotes the rapid synthesis of non-toxic Ca-MOF/COF@silica composites,which offers an innovative approach of greenly synthesizing novel MOF/COF stationary phases and extends their applications in the field of chromatography.
文摘A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance time can be shared by more than one component, and the system availability can be improved. Then, the generation characteristics of the random failure time are researched based on the replacement maintenance and the minima[ maintenance. Furthermore, by choosing the opportunistic replacement ages of each component as opti- mized variables, a simulation algorithm based on an opportunistic maintenance policy is designed to maximize the total availability. Finally, the simulation result shows the validity of the algorithm by an example.
基金Project supported by the National Natural Science Foundation of China(21571142)the Developing Science Fund of Tongji University,the Natural Science Foundation of Zhejiang Province(LQ14B010001)the Natural Science Foundation of Ningbo,China(2016A610105)
文摘This review focuses on the recent research progress in the multi-component assembly of luminescent rare earth hybrid materials, which is based on the luminescent rare earth compounds and two or more other building units, including the other photoactive species. It covers the multi-component luminescent rare earth hybrids which was assembled with different(a) organic-inorganic polymeric units,(b)nanoporous units,(c) nanoparticle composites or(d) other developing special units. Finally, future challenges and opportunities in this field are discussed. Herein it mainly focuses on the work of Yan's group in recent years.
文摘A general scheme for generating a multi-component integrable equation hierarchy is proposed. A simple 3M- dimensional loop algebra ~X is produced. By taking advantage of ~X a new isospectral problem is established and then by making use of the Tu scheme the multi-component Dirac equation hierarchy is obtained. Finally, an expanding loop algebra ~FM of the loop algebra ~X is presented. Based on the ~FM, the multi-component integrable coupling system of the multi-component Dirac equation hierarchy is investigated. The method in this paper can be applied to other nonlinear evolution equation hierarchies.
基金The research was supported by the Notion's Fifteenth Scientific and Technological Breakthrough Project: Research of Vector and Mountain Seismic Exploration (No.2001BA605A-12).
文摘Seismic AVO analysis now is one of the major criteria for recognizing potential hydrocarbon reservoirs. Volume scattering information that carries information of stratigraphic structure, lithology, and pore fluid is more useful for seismic exploration. However, traditional AVO analysis is based on the Zoeppritz equation, which only contains single-interface information. Quantitative interpretation of the thin bed thickness is essential to thin bed structure interpretation, reservoir description, and lateral reservoir prediction. The reflectance spectrum equation based on the elastic wave propagation matrix in the frequency domain derived in this paper shows that both interfaces and intervals have an effect on amplitude. The equation includes information about both single interfaces and volume scattering. Since the reflectance spectrum equation is a continuous function of thin bed thickness and frequency, it is convenient to analyze the effects of a single frequency and bed thickness on the reflectance spectrum. Bed thickness is analyzable until the bed thickness is vanishingly small. These characteristics can＇t be achieved by Fourier transform. The propagation of seismic waves is complex and various wave modes exist simultaneously. The reflectance spectrum includes various propagating wave modes and multiples and is better for simulating multi-component thin bed AVO responses than the ray tracing method.
基金supported by the National Natural Science Foundation of China Research(Nos.41574122 and 41374124)National Science and Technology major Project(No.2016ZX05006002-004)。
文摘The conventional digital core models are usually small in size and have difficulty in representing the complex structures of heterogeneous rocks;Therefore,the parameters of simulated rock physics are difficult to be referenced.In this study,we propose a feasible simulation method for obtaining multi-scale and multi-component digital cores based on three types of sandstone samples.In the proposed method,the plug and subplug samples are scanned via micro-computed tomography at different resolutions.Furthermore,the images are precisely registered using the proposed hybrid image registration method.In case of high-resolution images,the traditional segmentation method is used to segment the cores into pores and minerals.Subsequently,we established the relations between the gray values and the porosity/mineral content in case of the low-resolution images based on the registered domains and the relation curves were applied to the segmentation of the low-resolution images.The core images constitute the multi-scale and multi-component digital core models after segmentation.Further,the elastic properties of the three samples were simulated at both fine and coarse scales based on the multi-scale and multi-component digital core models,and four component models were considered.The results show that the multi-scale and multi-component digital core models can overcome the representative limits of the conventional digital core models and accurately characterize pores and minerals at different scales.The numerical results of the elastic modulus are more representative at large scales,and considerably reliable results can be obtained by appropriately considering the minerals.
基金supports from the National Natural Science Foundation of China (Grant No. 50931004)the National Basic Research Program of China (Grant Nos. 2011CB610406 and 2010CB631202)the National High Technology Research and Development Program (Grant No. 2007AA03Z552)
文摘The influence of melt superheating treatment on the solid/liquid （S/L） interface morphology of directionally solidified Ni-based superalloy DZ125 is investigated to elucidate the relationship between melt characteristic and S/L interface stability. The results indicate that the interface morphology is not only related to the withdrawal velocity （R） but also to the melt superheating temperature （Ts） when the thermal gradient of solidification interface remains constant for different Ts with appropriate superheating treatment regulation. The interface morphology changes from cell to plane at R of 1.1 μm/s when Ts increases from 1500°C to 1650°C, and maintains plane with further elevated Ts of 1750°C. However, the interface morphology changes from coarse dendrite to cell and then to cellular dendrite at R of 2.25 μm/s when Ts increases from 1500°C to 1650°C and then to 1750°C. It is proved that the solidification onset temperature and the solidification interval undergo the nonlinear variation when Ts increases from 1500°C to 1680°C, and the turning point is 1650°C at which the solidification onset temperature and the solidification interval are all minimum. This indicates that the melt superheating treatment enhances the solidification interface stability and has important effect on the solidification characteristics.
基金Project(71671035)supported by the National Natural Science Foundation of ChinaProjects(ZK15-03-01,ZK16-03-07)supported by Open Fund of Jiangsu Wind Power Engineering Technology Center of China
文摘Aiming at wind turbines,the opportunistic maintenance optimization is carried out for multi-component system,where minimal repair,imperfect repair,replacement as well as their effects on component’s effective age are considered.At each inspection point,appropriate maintenance mode is selected according to the component’s effective age and its maintenance threshold.To utilize the maintenance opportunities for the components among the wind turbines,opportunistic maintenance approach is adopted.Meanwhile,the influence of seasonal factor on the component’s failure rate and improvement factor’s decrease with the increase of repair’s times are also taken into account.The maintenance threshold is set as the decision variable,and an opportunistic maintenance optimization model is proposed to minimize wind turbine’s life-cycle maintenance cost.Moreover,genetic algorithm is adopted to solve the model,and the effectiveness is verified with a case study.The results show that based on the component’s inherent reliability and maintainability,the proposed model can provide optimal maintenance plans accordingly.Furthermore,the higher the component’s reliability and maintainability are,the less the times of repair and replacement will be.
基金Project(51005238)supported by the National Natural Science Foundation of China
文摘To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainability was analyzed, and the layout problem for maintainability was presented. It was formulated as an optimization problem, where maintainability, layout space and distance requirement were formulated as objective functions. A multi-objective particle swarm optimization algorithm, in which the constrained-domination relationship and the update strategy of the global best were simply modified, was then used to obtain Pareto optimal solutions for the maintainability layout design problem. Finally, application in oxygen generation system of a spacecraft was studied in detail to illustrate the effectiveness and usefulness of the proposed method. The results show that the concurrent maintainability design can be carried out during the layout design process by solving the layout optimization problem for maintainability.
基金National Key R&D Program of China(Grant Nos.2017YFC1702400,2018YFC1707300 and 2018YFC1707904)
文摘In the present study, a method for the quantitative analysis of multi-components by single marker(QAMS) has been developed and validated for the simultaneous determination of echinacoside(ECH), tubuloside A, acteoside, isoacteoside, and2’-acetylacteoside in Cistanches Herba. ECH was used as the internal standard(IS) to obtain the relative correction factors(RCFs) of the other four phenylethanoid glycosides(PhGs);meanwhile, various influencing factors on RCFs were investigated under different conditions. The content of each component was calculated with RCF. The results were compared with those obtained by the external standard method(ESM) to verify the feasibility and accuracy of the established QAMS method. No significant difference was found in the quantitative results of 10 batches of Cistanches Herba between QAMS and ESM. The proposed QAMS method for simultaneous determination of PhGs in Cistanches Herba is accurate and feasible, providing an efficient and economical approach for the quality control of Cistanches Herba.
