The skin wound is susceptible to bacterial invasion,which hinders the healing of the wound,especially when infected with multi-drug resistant strains.This demands novel bioactive materials to combat bacterial infectio...The skin wound is susceptible to bacterial invasion,which hinders the healing of the wound,especially when infected with multi-drug resistant strains.This demands novel bioactive materials to combat bacterial infections.In this study,gallium oxide nanoparticles(Ga_(2)O_(3) NPs)were successfully synthesized through high-temperature thermal decomposition,exhibiting excellent biocompatibility and photocatalytic antimicrobial activity.The Ga_(2)O_(3) NPs were crosslinked into chitosan hydrogel to create a light-responsive multilayered 3D porous hydrogel(Ga_(2)O_(3) NPs hydrogel)for use in photocatalytic antimicrobial therapy(PCAT).The prepared Ga_(2)O_(3) NPs hydrogel exhibits broad-spectrum photocatalytic activity and remarkable antibacterial efficacy against E.coli and S.aureus.It effectively eradicates biofilms,promotes reactive oxygen species production,disrupts bacterial cell membranes,and induces nucleic acid leakage,ultimately resulting in bacterial death.Additionally,it exhibits excellent biosafety.Both in vitro pigskin and in vivo mouse wound infection models have confirmed the remarkable efficacy of Ga_(2)O_(3) NPs hydrogel in PCAT.Notably,Ga_(2)O_(3) NPs hydrogel created a moist environment for the wound in an MDR S.aureus-infected mouse wound model,demonstrating significant potential to facilitate wound healing and minimize scar formation.This study introduces a novel hydrogel dressing without antibiotic components for resistant bacterial-infected wounds.展开更多
Lithium(Li)metal is considered the most promising anode material for the next generation of secondary batteries due to its high theoretical specific capacity and low potential.However,the application of Li anode in re...Lithium(Li)metal is considered the most promising anode material for the next generation of secondary batteries due to its high theoretical specific capacity and low potential.However,the application of Li anode in rechargeable Li metal batteries(LMBs)is hindered due to the short cycle life caused by uncontrolled dendrite growth.In this work,a dendrite-free anode(Li–Sn/Cu)is reinforced synergistically by lithophilic alloy,and a 3D grid structure is designed.Li^(+)diffusion and uniform nucleation are effectively induced by the lithophilic alloy Li_(22)Sn_(5).Moreover,homogeneous deposition of Li^(+)is caused by the reversible gridded Li plating/stripping effect of Cu mesh.Furthermore,the local space electric field is redistributed throughout the 3D conductive network,whereby the tip effect is suppressed,thus inhibiting the growth of Li dendrites.Also,the volume expansion of the anode during cycling is eased by the 3D grid structure.The results show that the Li–Sn/Cu symmetric battery can stably cycle for more than 10,000 h at 2 mA.cm^(-2)and 1 mAh.cm^(-2)with a low overpotential.The capacity retention of the LiFePO_(4)full battery remains above 90.7%after 1,000 cycles at 1C.This work provides a facile,low-cost,and effective strategy for obtaining Li metal batteries with ultra-long cycle life.展开更多
The integration of additive manufacturing(AM)in design and engineering has prompted a wide spectrum of research efforts,involving topologically optimized solid/lattice structures,multimaterial structures,bioinspired o...The integration of additive manufacturing(AM)in design and engineering has prompted a wide spectrum of research efforts,involving topologically optimized solid/lattice structures,multimaterial structures,bioinspired organic structures,and multiscale structures,to name a few.However,except for obvious cases,very little attention has been given to the design and printing of more complex three-dimensional(3D)hollow structures or folded/creased structures.One of the main reasons is that such complex open or closed 3D cavities and regular/freeform folds generally lead to printing difficulties from support-structure-related issues.To address this barrier,this paper aims to investigate four-dimensional(4D)printing as well as origami-based design as an original research direction to design and build 3D support-free hollow structures.This work consists of describing the rough 3D hollow structures in terms of two-dimensional(2D)printed origami precursor layouts without any support structure.Such origami-based definitions are then embodied with folding functions that can be actuated and fulfilled by 3D printed smart materials.The desired 3D shape is then built once an external stimulus is applied to the active materials,therefore ensuring the transformation of the 2D origami layout to 3D structures.To demonstrate the relevance of the proposal,some illustrative cases are introduced.展开更多
A bionic experimental platform was designed for the purpose of investigating time accurate three-dimensional flow field, using digital particle image velocimetry （DSPIV）. The wake behind the flapping trail of a robo...A bionic experimental platform was designed for the purpose of investigating time accurate three-dimensional flow field, using digital particle image velocimetry （DSPIV）. The wake behind the flapping trail of a robotic fish model was studied at high spatial resolution. The study was performed in a water channel. A robot fish model was designed and built. The model was fixed onto a rigid support frame- work using a cable-supporting method, with twelve stretched wires. The entire tail of the model can perform prescribed motions in two degrees of freedom, mainly in carangiform mode, by driving its afterbody and lunate caudal fin respectively. The DSPIV system was set up to operate in a trans- lational manner, measuring velocity field in a series of parallel slices. Phase locked measurements were repeated for a number of runs, allowing reconstruction of phase average flow field. Vortex structures with phase history of the wake were obtained. The study reveals some new and complex three-dimensional flow structures in the wake of the fish, including ＂reverse hairpin vortex＂ and ＂reverse Karman S-H vortex rings＂, allowing insight into physics of this complex flow.展开更多
A parametric method is developed to quantitatively represent the microstructure of 3D woven structures. Different binding patterns, such as angle interlock and orthogonal interlock with through-thickness or layer-to-l...A parametric method is developed to quantitatively represent the microstructure of 3D woven structures. Different binding patterns, such as angle interlock and orthogonal interlock with through-thickness or layer-to-layer bindings, are classified. A unit cell of 3D woven structure is defined with four constituent yarn systems represented by nine structural parameters. A mapping relationship between the 3D woven structure and corresponding representative parameters is thus established. The study indicates that four out of the nine parameters are necessary to represent a 3D woven structure with an angle interlock binding, and that five parameters are required to describe a 3D woven structure with an orthogonal interlock binding. Once the structural parameters are determined, the pattern of 3D woven structures can be unambiguously identified, and vice versa. In addition to the purpose of structure presentation, the method can be further used as a means for designing 3D woven structure to meet the performance requirements of 3D woven composites.展开更多
It has been shown that the progress in the determination of membrane protein structure grows exponentially, with approximately the same growth rate as that of the water-soluble proteins. In order to investigate the ef...It has been shown that the progress in the determination of membrane protein structure grows exponentially, with approximately the same growth rate as that of the water-soluble proteins. In order to investigate the effect of this, on the performance of prediction algorithms for both α-helical and β-barrel membrane proteins, we conducted a prospective study based on historical records. We trained separate hidden Markov models with different sized training sets and evaluated their performance on topology prediction for the two classes of transmembrane proteins. We show that the existing top-scoring algorithms for predicting the transmembrane segments of α-helical membrane proteins perform slightly better than that of β-barrel outer membrane proteins in all measures of accuracy. With the same rationale, a metaoanalysis of the performance of the secondary structure prediction algorithms indicates that existing algorithmic techniques cannot be further improved by just adding more non-homologous sequences to the training sets. The upper limit for secondary structure prediction is estimated to be no more than 70% and 80% of correctly predicted residues for single sequence based methods and multiple sequence based ones, respectively. Therefore, we should concentrate our efforts on utilizing new techniques for the development of even better scoring predictors.展开更多
The high energy density and long cycling life of zinc-based batteries are restricted by the single electro-chemical reaction system.To improve the electrochemical performance of batteries,electrode materials,electroly...The high energy density and long cycling life of zinc-based batteries are restricted by the single electro-chemical reaction system.To improve the electrochemical performance of batteries,electrode materials,electrolytes and membranes are regularly modified,while the construction of battery systems is often ne-glected.Herein,a multifunctional electrode was prepared via 3D printing,which successfully coupled the metal oxide/hydroxide-zinc battery(MZB)reaction and rechargeable zinc-air battery(RZAB)reaction.The ultrathick hierarchical 3D electrode provided a tunable capacity for the MZB system,which enabled the possibility for feasible output regulation of this hybrid system.The active material NiCoLDH was discov-ered to undergo structure reconstruction during cycling,which revealed the capacity fading mechanism.The delicate system design and discovery ensured a high-performance battery configuration and revealed the corresponding mechanism,opening a new avenue for developing high-performance zinc batteries.展开更多
The balancing of the electrochemical performance,mechanical stability,and processing technology for applying supercapacitors to flexible and wearable electronics continues to encounter severe challenges.Herein,we prep...The balancing of the electrochemical performance,mechanical stability,and processing technology for applying supercapacitors to flexible and wearable electronics continues to encounter severe challenges.Herein,we prepare Ni-Co-Mn hydroxide electrodes with a threedimensional multichannel structure via a simple hydrothermal method.These are constructed using vertically contiguous nano sheets with a uniform thickness and rough surface.The electrodes can provide numerous electroactive sites and accelerate the transmission of electrolyte ions.The relationship between the structure and electrochemical performances is verified by experiments and theoretical calculations.Two-dimensional(2D)planar and one-dimensional(1D)fiber electrodes are prepared using a flexible carbon cloth(CC)and carbon fiber(CF),respectively,as substrates.The assembled quasi-solid-state flexible asymmetric supercapacitor(FASC)with a twodimensional sandwich structure using NiCoMn-OH/CC as the electrode achieves a remarkable energy density of73.8 Wh·kg^(-1)at a power density of 1.03 kW·kg^(-1).The quasi-solid-state FASC with a 1D linear structure using NiCoMn-OH/CF as the electrode also attains a high energy density(12.9 Wh·kg^(-1)at a power density of0.75 W·kg^(-1)).Moreover,the electrochemical performances of the NiCoMn/CC//AC/CC and NiCoMn/CF//AC/CF FASCs are not disturbed at different bending angles(0°,45°,90°,135°and 180°),This indicates the superior flexibility of the devices.We also assemble a self-powered energy-harvesting storage system by integrating FASCs and commercial solar cells to verify its practicability.It displays sustainable development potential for energy storage.展开更多
The larger ionic radius of potassium ions than that of lithium ions significantly limits the accomplishment of rapid diffusion kinetics in graphite electrodes for potassium-ion batteries(PIBs),resulting in comparative...The larger ionic radius of potassium ions than that of lithium ions significantly limits the accomplishment of rapid diffusion kinetics in graphite electrodes for potassium-ion batteries(PIBs),resulting in comparatively poor rate performance and cycle stability.Herein,we report a high-rate performance and cycling stability amorphous carbon electrode achieved through nitrogen and phosphorous co-doping.The as-prepared N,P co-doped carbon electrodes have distinct 3D structures with large surface areas,hierarchical pore architectures,and increased interlayer spaces resulting from the direct pyrolysis of supramolecular self-assembled aggregates without templates.The obtained electrode N3P1 exhibits a reversible specific capacity of 258 m Ah·g^(-1)at a current density of 0.1A·g^(-1)and a good long-term cycle performance(96.1%capacity retention after 800 cycles at 0.5 A·g^(-1)).Kinetic investigations show that the N3P1 electrode with the welldeveloped porous structure and large number of surface defects exhibits capacitive-driven behavior at all scan rates,which may be attributed by N and P co-doping.Ex-situ transmission electron microscopy analyses in the fully discharged and charged states demonstrate structural stability and reversibility owing to the expanded interlayer space.The suggested synthesis approach is simple and effective for producing heteroatom-doped carbon materials for PIBs and other advanced electrochemical energy storage materials.展开更多
Graphene nanoplates(GNPs)and carbon nanotubes(CNTs)can construct efficient thermal flux channels in composites,which is becoming one of the effective methods to improve thermal conductivity(TC)of composites.In this pa...Graphene nanoplates(GNPs)and carbon nanotubes(CNTs)can construct efficient thermal flux channels in composites,which is becoming one of the effective methods to improve thermal conductivity(TC)of composites.In this paper,an emerging class of GNPs&MWCNTs preform with 3D orientated structures were prepared by using electrostatic self-assembly and directional freeze-drying methods,and then fabricated the GNPs&MWCNTs reinforced AZ91D magnesium(GNPs&MWCNTs/AZ91D)composites by squeeze casting process.To ensure the well preparation of the composites,the GNPs&MWCNTs preforms need to possess enough compression strength to withstand squeezing pressure.Therefore,the effects of the electrostatic self-assembly process,directional freeze drying process and thermal reduction process on the compression strength of 3D structure GNPs&MWCNTs preforms were studied.The compression strength of GNPs&MWCNTs preforms were well improved to 98 KPa,which were used for the fabrication of AZ91D matrix composites.The TC of 0.5 wt.%(1:1)GNPs&MWCNTs/AZ91D composites reached 71.7 W/(m·K)in the freezing direction,which was 41.8%higher than that(50.6 W/(m·K))of the AZ91D alloy.This work provides a novel method for preparing GNPs&MWCNTs/AZ91D composites with improved TCs.展开更多
Methods and procedures of three-dimensional （3D） characterization of the pore structure features in the packed ore particle bed are focused. X-ray computed tomography was applied to deriving the cross-sectional imag...Methods and procedures of three-dimensional （3D） characterization of the pore structure features in the packed ore particle bed are focused. X-ray computed tomography was applied to deriving the cross-sectional images of specimens with single particle size of 1-2, 2-3, 3-4, 4-5, 5-6, 6-7, 7-8, 8-9, 9-10 ram. Based on the in-house developed 3D image analysis programs using Matlab, the volume porosity, pore size distribution and degree of connectivity were calculated and analyzed in detail. The results indicate that the volume porosity, the mean diameter of pores and the effective pore size （d50） increase with the increasing of particle size. Lognormal distribution or Gauss distribution is mostly suitable to model the pore size distribution. The degree of connectivity investigated on the basis of cluster-labeling algorithm also increases with increasing the particle size approximately.展开更多
Understanding the continental margin of the Northeastern South China Sea is critical to the study of deep structures, tectonic evolution, and dynamics of the region. One set of important data for this endeavor is the ...Understanding the continental margin of the Northeastern South China Sea is critical to the study of deep structures, tectonic evolution, and dynamics of the region. One set of important data for this endeavor is the total-field magnetic data. Given the challenges associated with the magnetic data at low latitudes and with remanent magnetism in this area, we combine the equivalent-source technique and magnetic amplitude inversion to recover 3D subsurface magnetic structures. The inversion results show that this area is characterized by a north-south block division and east-west zonation. Magnetic regions strike in EW, NE and NW direction and are consistent with major tectonic trends in the region. The highly magnetic zone recovered from inversion in the continental margin differs visibly from that of the magnetically quiet zones to the south. The magnetic anomaly zone strikes in NE direction, covering an area of about 500 km × 60 km, and extending downward to a depth of 25 km or more. In combination with other geophysical data, we suggest that this strongly magnetic zone was produced by deep underplating of magma associated with plate subduction in Mesozoic period. The magnetically quiet zone in the south is an EW trending unit underlain by broad and gentle magnetic layers of lower crust. Its magnetic structure bears a clear resemblance to oceanic crust, assumed to be related to the presence of ancient oceanic crust there.展开更多
Herein,a novel label-free electrochemical immunosensor was fabricated via immobilizing specific anti-β-lactoglobulin(β-LG)antibodies(Abs)onto an integrated electrode of gold nanoparticles(AuNPs)/Prussian blue(PB)/cu...Herein,a novel label-free electrochemical immunosensor was fabricated via immobilizing specific anti-β-lactoglobulin(β-LG)antibodies(Abs)onto an integrated electrode of gold nanoparticles(AuNPs)/Prussian blue(PB)/cubic Ia3d structured mesoporous carbon(CMK-8).This immunosensor allowed for the quantitative detection of the major milk allergenβ-LG.CMK-8 with excellent electrical conductivity and uniformly adjustable pore structure was modified on the glassy carbon electrode(GCE)and served as the sensitive substrate for the electro-polymerization of PB,forming the redox-active layer.AuNPs were subsequently electrochemically deposited on PB/CMK-8/GCE to improve the electrical conductivity and utilized as the connector for Abs immobilization.Duringβ-LG detection,the Abs-modified AuNPs/PB/CMK-8/GCE exhibited a significant reduction in differential pulse voltammetry current signal when exposed toβ-LG,displaying an inverse dose-dependent relationship.The developed electrochemical immunosensor demonstrated good detection performance forβ-LG,with a wider linear range of 0.01-100 ng/mL and a lower detection limit of 4.72 pg/mL.Meanwhile,the sensor exhibited remarkable repeatability,reproducibility,stability and anti-interference capabilities,which was further applied to detectβ-LG in dairy food,achieving satisfactory recoveries(89.2%-98.8%)and lower relative standard deviation(£3.1%).Therefore,this innovative electrochemical method for food allergen detection holds great potential application in food safety determination and evaluation.展开更多
Producing hydrogen peroxide(H_(2)O_(2))through visible-light-driven photocatalytic oxygen reduction in pure water is crucial for sustainable ecological applications but poses significant challenges.It include the rapi...Producing hydrogen peroxide(H_(2)O_(2))through visible-light-driven photocatalytic oxygen reduction in pure water is crucial for sustainable ecological applications but poses significant challenges.It include the rapid recombination of electron-hole pairs and a scarcity of effective catalytic sites,which traditionally limit the process efficiency.To address these issues,we have developed a novel catalyst,designated as KCNOH,which consists of a three-dimensional(3D)porous g-C_(3)N_(4)framework doped with potassium(K^(+))and modified with surface hydroxyl groups(–OH).This design significantly enhances H_(2)O_(2)yield,achieving 91.36μmol g^(-1)h^(-1)(cut 420 nm)-a yield approximately 36 times higher than conventional bulk g-C_(3)N_(4)(2.57μmol g^(-1)h^(-1)).The introduction of a 3D porous structure provides an abundance of active-sites.The dual-dipole mechanism,facilitated by K^(+) ions and hydroxyl groups,plays a pivotal role by efficiently transporting photogenerated electrons and consuming holes,respectively.Through density functional theory(DFT)calculations,the changes in the band structure of the catalyst caused by the doping of K^(+) and the grafting of–OH were elucidated.In addition,the transition state affinity of oxygen induced by the–OH was also studied to reveal the synergistic catalytic mechanism.This mechanism markedly reduces carrier recombination and accelerates charge migration,underscoring its importance in catalyst design.Our findings not only improve the understanding of charge dynamics but also open novel perspectives for the design of highly-efficient composite materials,which is crucial for energy and environmental applications.展开更多
Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.T...Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.This study investigates the effects of Ti Cu precursor compositions on dealloying behavior and microstructural evolution in liquid Mg,using Ti_(50)Cu_(50)and Ti_(30)Cu_(70)precursors.The initial microstructure of the precursor significantly influences dealloying kinetics and phase transitions.The single-phase Ti_(50)Cu_(50)precursor exhibits a faster initial dealloying rate due to its homogeneous structure,yet complete dealloying requires 90 min.In contrast,the dualphase Ti_(30)Cu_(70)precursor achieves complete dealloying in 30 min,demonstrating the impact of a higher Cu concentration on accelerating the process kinetics.Additionally,the study explores the coarsening behavior and hardness variations during the LMD process,along with the microstructural characteristics of Mg-Ti composites fabricated from these two precursors.The findings highlight the critical role of precursor composition in tailoring the microstructure and properties of Mg-Ti composites produced through the LMD process,demonstrating its potential for advanced composite material manufacturing.展开更多
Although anisotropic NMR spectroscopy has emerged as a powerful method for determining the relative configuration of complex natural products,major challenges persist with structurally flexible molecules.In this study...Although anisotropic NMR spectroscopy has emerged as a powerful method for determining the relative configuration of complex natural products,major challenges persist with structurally flexible molecules.In this study,we conducted a system-atic comparative analysis of stereochemical elucidation,combining anisotropic NMR spectroscopy and density functional theory(DFT)calculations on spiroepicoccin B(1)and epicoccin V(2),which were characterized as thiodiketopiperazine marine natural products isolated from the deep-sea-derived fungus Epicoccum nigrum SD-388.For the flexible compound 2,we compared various conformational sampling approaches,including an assessment of the quality of relative energies within the obtained ensembles.We demonstrated the critical role of dispersion correction within DFT computations to precisely account for weak non-bonded intramolecular interactions.By integrating anisotropic NMR analysis,chemical shifts,elec-tronic circular dichroism,and DFT computations,we determined the absolute configurations and conformational ensembles for 1 and 2,respectively,highlighting the significance of the intramolecular methyl-πinteraction in stabilizing one of the conformers.Our study introduces new strategies to address conformational flexibility in the stereochemical elucidation of challenging organic molecules.展开更多
The Nanling-Xuancheng ore region of Anhui Province is located in the Middle-Lower Yangtze River metallogenic belt.Insufficient exploration and research have been carried out in this newly defined ore district,although...The Nanling-Xuancheng ore region of Anhui Province is located in the Middle-Lower Yangtze River metallogenic belt.Insufficient exploration and research have been carried out in this newly defined ore district,although the Chating large porphyry Cu-Au deposit and a few middle-sized skarntype Cu polymetallic deposits have been discovered.In this study,we carried out high-resolution seismic reflection,magnetotelluric,gravity,and magnetic investigations,and constructed the 3 D geological structure of the uppermost crust in a depth range of 0-5 km using a comprehensive inversion of the new data constrained by previous deep-drilling data.We hence proposed some new insights to understand the mineralization processes of this district.A system of alternating ridges and valleys is suggested as the major structure pattern,composed of“two-layer structure”of the basins and“three-layer structure”of anticlines.Moreover,a conjugated fault system and its distribution features are revealed in our models,including the Jiangnan fault,Zhouwang fault,and Kunshan thrust nappe.The Jiangnan and Kunshan faults are suggested to have controlled the diagenesis and metallogenesis.Two deep concealed plutons located in Chating and Magushan are found,forming the Mesozoic diorite-felsic intrusions.These intrusions are believed to be the causes of hydrothermal deposits such as the Chating deposit and the Magushan deposit.展开更多
Faults and fractures of multiple scales are frequently induced and generated in compressional structural system. Comprehensive identification of these potential faults and fractures that cannot be distinguished direct...Faults and fractures of multiple scales are frequently induced and generated in compressional structural system. Comprehensive identification of these potential faults and fractures that cannot be distinguished directly from seismic profile of the complex structures is still an unanswered problem. Based on the compressional structural geometry and kinematics theories as well as the structural interpretation from seismic data, a set of techniques is established for the identification of potential faults and fractures in compressional structures. Firstly, three-dimensional(3D) patterns and characteristics of the faults directly interpreted from seismic profile were illustrated by 3D structural model. Then, the unfolding index maps, the principal structural curvature maps, and tectonic stress field maps were obtained from structural restoration. Moreover, potential faults and fractures in compressional structures were quantitatively identified relying on comprehensive analysis of these three maps. Successful identification of the potential faults and fractures in Mishrif limestone formation and in Asmari dolomite formation of Buzurgan anticline in Iraq demonstrates the applicability and reliability of these techniques.展开更多
The special seismic tectonic environment and frequent seismicity in the southeastern margin of the Qinghai-Tibet Plateau show that this area is an ideal location to study the present tectonic movement and background o...The special seismic tectonic environment and frequent seismicity in the southeastern margin of the Qinghai-Tibet Plateau show that this area is an ideal location to study the present tectonic movement and background of strong earthquakes in China's Mainland and to predict future strong earthquake risk zones. Studies of the structural environment and physical characteristics of the deep structure in this area are helpful to explore deep dynamic effects and deformation field characteristics, to strengthen our understanding of the roles of anisotropy and tectonic deformation and to study the deep tectonic background of the seismic origin of the block＇s interior. In this paper, the three-dimensional （3D） P-wave velocity structure of the crust and upper mantle under the southeastern margin of the Qinghai-Tibet Plateau is obtained via observational data from 224 permanent seismic stations in the regional digital seismic network of Yunnan and Sichuan Provinces and from 356 mobile China seismic arrays in the southern section of the north-south seismic belt using a joint inversion method of the regional earthquake and teleseismic data. The results indicate that the spatial distribution of the P-wave velocity anomalies in the shallow upper crust is closely related to the surface geological structure, terrain and lithology. Baoxing and Kangding, with their basic volcanic rocks and volcanic clastic rocks, present obvious high-velocity anomalies. The Chengdu Basin shows low-velocity anomalies associated with the Quaternary sediments. The Xichang Mesozoic Basin and the Butuo Basin are characterised by low- velocity anomalies related to very thick sedimentary layers. The upper and middle crust beneath the Chuan-Dian and Songpan-Ganzi Blocks has apparent lateral heterogeneities, including low-velocity zones of different sizes. There is a large range of low-velocity layers in the Songpan-Ganzi Block and the sub-block northwest of Sichuan Province, showing that the middle and lower crust is relatively weak. The Sichuan Basin, which is located in the western margin of the Yangtze platform, shows high-velocity characteristics. The results also reveal that there are continuous low-velocity layer distributions in the middle and lower crust of the Daliangshan Block and that the distribution direction of the low-velocity anomaly is nearly SN, which is consistent with the trend of the Daliangshan fault. The existence of the low-velocity layer in the crust also provides a deep source for the deep dynamic deformation and seismic activity of the Daliangshan Block and its boundary faults. The results of the 3D P-wave velocity structure show that an anomalous distribution of high-density, strong-magnetic and high-wave velocity exists inside the crust in the Panxi region. This is likely related to late Paleozoic mantle plume activity that led to a large number of mafic and ultra-mafic intrusions into the crust. In the crustal doming process, the massive intrusion of mantle-derived material enhanced the mechanical strength of the crustal medium. The P-wave velocity structure also revealed that the upper mantle contains a low-velocity layer at a depth of 80-120 km in the Panxi region. The existence of deep faults in the Panxi region, which provide conditions for transporting mantle thermal material into the crust, is the deep tectonic background for the area＇s strong earthquake activity.展开更多
Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error...Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error detection and dynamic correction in 3D geological structure models,we have reviewed the current situation and development trends in 3D geological modeling.The main context of uncertainty in 3D geological structure models is discussed.Major research issues and a general framework system of uncertainty in 3D geological structure models are proposed.We have described in detail the integration of development practices of 3D geological modeling systems,as well as the implementation process for uncertainty evaluation in 3D geological structure models.This study has laid the basis to build theoretical and methodological systems for accuracy assessment and error correction in 3D geological models and can assist in improving 3D modeling techniques under complex geological conditions.展开更多
基金financially supported by the Advanced Fiber Materials Engineering Research Center of Anhui Province(No.2023AFMC20)the Scientific Research Foundation for Advanced Talents of Anhui Polytechnic University(No.2022YQQ072)+5 种基金the Anhui Province Key Research and Development Program(No.2022i01020002)the Key Project Foundation of Anhui Higher Education Institutes of China(No.2023AH050941)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.22KJB180020)the Transversal Project(No.KH10004443),the Anhui Provincial Natural Science Foundation(No.2308085Y45)the Program for Excellent Sci-tech Innovation Teams of Universities in Anhui Province(No.2023AH010073)Wuhu Science and Technology Department project(No.2023jc22).
文摘The skin wound is susceptible to bacterial invasion,which hinders the healing of the wound,especially when infected with multi-drug resistant strains.This demands novel bioactive materials to combat bacterial infections.In this study,gallium oxide nanoparticles(Ga_(2)O_(3) NPs)were successfully synthesized through high-temperature thermal decomposition,exhibiting excellent biocompatibility and photocatalytic antimicrobial activity.The Ga_(2)O_(3) NPs were crosslinked into chitosan hydrogel to create a light-responsive multilayered 3D porous hydrogel(Ga_(2)O_(3) NPs hydrogel)for use in photocatalytic antimicrobial therapy(PCAT).The prepared Ga_(2)O_(3) NPs hydrogel exhibits broad-spectrum photocatalytic activity and remarkable antibacterial efficacy against E.coli and S.aureus.It effectively eradicates biofilms,promotes reactive oxygen species production,disrupts bacterial cell membranes,and induces nucleic acid leakage,ultimately resulting in bacterial death.Additionally,it exhibits excellent biosafety.Both in vitro pigskin and in vivo mouse wound infection models have confirmed the remarkable efficacy of Ga_(2)O_(3) NPs hydrogel in PCAT.Notably,Ga_(2)O_(3) NPs hydrogel created a moist environment for the wound in an MDR S.aureus-infected mouse wound model,demonstrating significant potential to facilitate wound healing and minimize scar formation.This study introduces a novel hydrogel dressing without antibiotic components for resistant bacterial-infected wounds.
基金supported by the National Natural Science Foundation of China(No.52401221)Shandong Provincial Natural Science Foundation,China(No.ZR2022QE014)+1 种基金the Basic Scientific Research Fund for Central Universities(No.202112018)the Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)。
文摘Lithium(Li)metal is considered the most promising anode material for the next generation of secondary batteries due to its high theoretical specific capacity and low potential.However,the application of Li anode in rechargeable Li metal batteries(LMBs)is hindered due to the short cycle life caused by uncontrolled dendrite growth.In this work,a dendrite-free anode(Li–Sn/Cu)is reinforced synergistically by lithophilic alloy,and a 3D grid structure is designed.Li^(+)diffusion and uniform nucleation are effectively induced by the lithophilic alloy Li_(22)Sn_(5).Moreover,homogeneous deposition of Li^(+)is caused by the reversible gridded Li plating/stripping effect of Cu mesh.Furthermore,the local space electric field is redistributed throughout the 3D conductive network,whereby the tip effect is suppressed,thus inhibiting the growth of Li dendrites.Also,the volume expansion of the anode during cycling is eased by the 3D grid structure.The results show that the Li–Sn/Cu symmetric battery can stably cycle for more than 10,000 h at 2 mA.cm^(-2)and 1 mAh.cm^(-2)with a low overpotential.The capacity retention of the LiFePO_(4)full battery remains above 90.7%after 1,000 cycles at 1C.This work provides a facile,low-cost,and effective strategy for obtaining Li metal batteries with ultra-long cycle life.
基金the Ministère de l’Enseignement Supérieur et de la Recherche, the French ‘Investissements d’Avenir’ program, project ISITE-BFC (contract ANR-15-IDEX-0003)China Scholarship Council as the main financial supports of this research program
文摘The integration of additive manufacturing(AM)in design and engineering has prompted a wide spectrum of research efforts,involving topologically optimized solid/lattice structures,multimaterial structures,bioinspired organic structures,and multiscale structures,to name a few.However,except for obvious cases,very little attention has been given to the design and printing of more complex three-dimensional(3D)hollow structures or folded/creased structures.One of the main reasons is that such complex open or closed 3D cavities and regular/freeform folds generally lead to printing difficulties from support-structure-related issues.To address this barrier,this paper aims to investigate four-dimensional(4D)printing as well as origami-based design as an original research direction to design and build 3D support-free hollow structures.This work consists of describing the rough 3D hollow structures in terms of two-dimensional(2D)printed origami precursor layouts without any support structure.Such origami-based definitions are then embodied with folding functions that can be actuated and fulfilled by 3D printed smart materials.The desired 3D shape is then built once an external stimulus is applied to the active materials,therefore ensuring the transformation of the 2D origami layout to 3D structures.To demonstrate the relevance of the proposal,some illustrative cases are introduced.
基金supported by the National Natural Science Foundation of China (10772017 and 10472011)BUAA-985 Foundation
文摘A bionic experimental platform was designed for the purpose of investigating time accurate three-dimensional flow field, using digital particle image velocimetry （DSPIV）. The wake behind the flapping trail of a robotic fish model was studied at high spatial resolution. The study was performed in a water channel. A robot fish model was designed and built. The model was fixed onto a rigid support frame- work using a cable-supporting method, with twelve stretched wires. The entire tail of the model can perform prescribed motions in two degrees of freedom, mainly in carangiform mode, by driving its afterbody and lunate caudal fin respectively. The DSPIV system was set up to operate in a trans- lational manner, measuring velocity field in a series of parallel slices. Phase locked measurements were repeated for a number of runs, allowing reconstruction of phase average flow field. Vortex structures with phase history of the wake were obtained. The study reveals some new and complex three-dimensional flow structures in the wake of the fish, including ＂reverse hairpin vortex＂ and ＂reverse Karman S-H vortex rings＂, allowing insight into physics of this complex flow.
基金the Research Fund for the Doctoral Program of Higher Education and the Shanghai Key Discipline Project
文摘A parametric method is developed to quantitatively represent the microstructure of 3D woven structures. Different binding patterns, such as angle interlock and orthogonal interlock with through-thickness or layer-to-layer bindings, are classified. A unit cell of 3D woven structure is defined with four constituent yarn systems represented by nine structural parameters. A mapping relationship between the 3D woven structure and corresponding representative parameters is thus established. The study indicates that four out of the nine parameters are necessary to represent a 3D woven structure with an angle interlock binding, and that five parameters are required to describe a 3D woven structure with an orthogonal interlock binding. Once the structural parameters are determined, the pattern of 3D woven structures can be unambiguously identified, and vice versa. In addition to the purpose of structure presentation, the method can be further used as a means for designing 3D woven structure to meet the performance requirements of 3D woven composites.
基金PGB was supported by a scholarship from the State Scholarships Foundation of Greece (SSF) for postdoctoral research in the Department of Cell Biology and Biophysics of the University of Athens (Machine Learning Algorithms for Bioinformatics)
文摘It has been shown that the progress in the determination of membrane protein structure grows exponentially, with approximately the same growth rate as that of the water-soluble proteins. In order to investigate the effect of this, on the performance of prediction algorithms for both α-helical and β-barrel membrane proteins, we conducted a prospective study based on historical records. We trained separate hidden Markov models with different sized training sets and evaluated their performance on topology prediction for the two classes of transmembrane proteins. We show that the existing top-scoring algorithms for predicting the transmembrane segments of α-helical membrane proteins perform slightly better than that of β-barrel outer membrane proteins in all measures of accuracy. With the same rationale, a metaoanalysis of the performance of the secondary structure prediction algorithms indicates that existing algorithmic techniques cannot be further improved by just adding more non-homologous sequences to the training sets. The upper limit for secondary structure prediction is estimated to be no more than 70% and 80% of correctly predicted residues for single sequence based methods and multiple sequence based ones, respectively. Therefore, we should concentrate our efforts on utilizing new techniques for the development of even better scoring predictors.
基金National Natural Science Foundation of China(No.52272234)National Key Research and Development Program of China(No.2020YFA0715000)+2 种基金Key Research and Development Program of Hubei Province(No.2021BAA070)independent Innovation Projects of the Hubei Longzhong Laboratory(No.2022ZZ-20)Sanya Science and Education Innovation Park of Wuhan University of Technology(No.2021KF0011).
文摘The high energy density and long cycling life of zinc-based batteries are restricted by the single electro-chemical reaction system.To improve the electrochemical performance of batteries,electrode materials,electrolytes and membranes are regularly modified,while the construction of battery systems is often ne-glected.Herein,a multifunctional electrode was prepared via 3D printing,which successfully coupled the metal oxide/hydroxide-zinc battery(MZB)reaction and rechargeable zinc-air battery(RZAB)reaction.The ultrathick hierarchical 3D electrode provided a tunable capacity for the MZB system,which enabled the possibility for feasible output regulation of this hybrid system.The active material NiCoLDH was discov-ered to undergo structure reconstruction during cycling,which revealed the capacity fading mechanism.The delicate system design and discovery ensured a high-performance battery configuration and revealed the corresponding mechanism,opening a new avenue for developing high-performance zinc batteries.
基金financially supported by Tianjin Municipal Education Commission Scientific Research Project(No.2018KJ151)the National Natural Science Foundation of China(No.51773094)Tianjin Research Innovation Project for Postgraduate Students(No.2021YJSB245)。
文摘The balancing of the electrochemical performance,mechanical stability,and processing technology for applying supercapacitors to flexible and wearable electronics continues to encounter severe challenges.Herein,we prepare Ni-Co-Mn hydroxide electrodes with a threedimensional multichannel structure via a simple hydrothermal method.These are constructed using vertically contiguous nano sheets with a uniform thickness and rough surface.The electrodes can provide numerous electroactive sites and accelerate the transmission of electrolyte ions.The relationship between the structure and electrochemical performances is verified by experiments and theoretical calculations.Two-dimensional(2D)planar and one-dimensional(1D)fiber electrodes are prepared using a flexible carbon cloth(CC)and carbon fiber(CF),respectively,as substrates.The assembled quasi-solid-state flexible asymmetric supercapacitor(FASC)with a twodimensional sandwich structure using NiCoMn-OH/CC as the electrode achieves a remarkable energy density of73.8 Wh·kg^(-1)at a power density of 1.03 kW·kg^(-1).The quasi-solid-state FASC with a 1D linear structure using NiCoMn-OH/CF as the electrode also attains a high energy density(12.9 Wh·kg^(-1)at a power density of0.75 W·kg^(-1)).Moreover,the electrochemical performances of the NiCoMn/CC//AC/CC and NiCoMn/CF//AC/CF FASCs are not disturbed at different bending angles(0°,45°,90°,135°and 180°),This indicates the superior flexibility of the devices.We also assemble a self-powered energy-harvesting storage system by integrating FASCs and commercial solar cells to verify its practicability.It displays sustainable development potential for energy storage.
基金financially supported by the National Research Foundation of Korea(NRF)from Korean government(MSIT,Korea)(No.2023R1A2C1005459)the Materials/Parts Technology Development Program from the Ministry of Trade,Industry,and Energy(MOTIE,Korea)(No.20019205)。
文摘The larger ionic radius of potassium ions than that of lithium ions significantly limits the accomplishment of rapid diffusion kinetics in graphite electrodes for potassium-ion batteries(PIBs),resulting in comparatively poor rate performance and cycle stability.Herein,we report a high-rate performance and cycling stability amorphous carbon electrode achieved through nitrogen and phosphorous co-doping.The as-prepared N,P co-doped carbon electrodes have distinct 3D structures with large surface areas,hierarchical pore architectures,and increased interlayer spaces resulting from the direct pyrolysis of supramolecular self-assembled aggregates without templates.The obtained electrode N3P1 exhibits a reversible specific capacity of 258 m Ah·g^(-1)at a current density of 0.1A·g^(-1)and a good long-term cycle performance(96.1%capacity retention after 800 cycles at 0.5 A·g^(-1)).Kinetic investigations show that the N3P1 electrode with the welldeveloped porous structure and large number of surface defects exhibits capacitive-driven behavior at all scan rates,which may be attributed by N and P co-doping.Ex-situ transmission electron microscopy analyses in the fully discharged and charged states demonstrate structural stability and reversibility owing to the expanded interlayer space.The suggested synthesis approach is simple and effective for producing heteroatom-doped carbon materials for PIBs and other advanced electrochemical energy storage materials.
基金supported by the National Natural Science Foundation of China(grant numbers 52231004,51972271 and 52205415)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110034)。
文摘Graphene nanoplates(GNPs)and carbon nanotubes(CNTs)can construct efficient thermal flux channels in composites,which is becoming one of the effective methods to improve thermal conductivity(TC)of composites.In this paper,an emerging class of GNPs&MWCNTs preform with 3D orientated structures were prepared by using electrostatic self-assembly and directional freeze-drying methods,and then fabricated the GNPs&MWCNTs reinforced AZ91D magnesium(GNPs&MWCNTs/AZ91D)composites by squeeze casting process.To ensure the well preparation of the composites,the GNPs&MWCNTs preforms need to possess enough compression strength to withstand squeezing pressure.Therefore,the effects of the electrostatic self-assembly process,directional freeze drying process and thermal reduction process on the compression strength of 3D structure GNPs&MWCNTs preforms were studied.The compression strength of GNPs&MWCNTs preforms were well improved to 98 KPa,which were used for the fabrication of AZ91D matrix composites.The TC of 0.5 wt.%(1:1)GNPs&MWCNTs/AZ91D composites reached 71.7 W/(m·K)in the freezing direction,which was 41.8%higher than that(50.6 W/(m·K))of the AZ91D alloy.This work provides a novel method for preparing GNPs&MWCNTs/AZ91D composites with improved TCs.
基金Projects(50934002,51074013,51304076,51104100)supported by the National Natural Science Foundation of ChinaProject(IRT0950)supported by the Program for Changjiang Scholars Innovative Research Team in Universities,ChinaProject(2012M510007)supported by China Postdoctoral Science Foundation
文摘Methods and procedures of three-dimensional （3D） characterization of the pore structure features in the packed ore particle bed are focused. X-ray computed tomography was applied to deriving the cross-sectional images of specimens with single particle size of 1-2, 2-3, 3-4, 4-5, 5-6, 6-7, 7-8, 8-9, 9-10 ram. Based on the in-house developed 3D image analysis programs using Matlab, the volume porosity, pore size distribution and degree of connectivity were calculated and analyzed in detail. The results indicate that the volume porosity, the mean diameter of pores and the effective pore size （d50） increase with the increasing of particle size. Lognormal distribution or Gauss distribution is mostly suitable to model the pore size distribution. The degree of connectivity investigated on the basis of cluster-labeling algorithm also increases with increasing the particle size approximately.
基金supported by the Chinese Scholarship Foundation,the Gravity and Magnetics Research Consortium(GMRC)the National Natural Science Foundation of China(No.41074095)+1 种基金the National Special Project(No.201011039)the Open Project of the National Key Laboratory for Geological Processes and Mineral Resources(No.GPMR0942)
文摘Understanding the continental margin of the Northeastern South China Sea is critical to the study of deep structures, tectonic evolution, and dynamics of the region. One set of important data for this endeavor is the total-field magnetic data. Given the challenges associated with the magnetic data at low latitudes and with remanent magnetism in this area, we combine the equivalent-source technique and magnetic amplitude inversion to recover 3D subsurface magnetic structures. The inversion results show that this area is characterized by a north-south block division and east-west zonation. Magnetic regions strike in EW, NE and NW direction and are consistent with major tectonic trends in the region. The highly magnetic zone recovered from inversion in the continental margin differs visibly from that of the magnetically quiet zones to the south. The magnetic anomaly zone strikes in NE direction, covering an area of about 500 km × 60 km, and extending downward to a depth of 25 km or more. In combination with other geophysical data, we suggest that this strongly magnetic zone was produced by deep underplating of magma associated with plate subduction in Mesozoic period. The magnetically quiet zone in the south is an EW trending unit underlain by broad and gentle magnetic layers of lower crust. Its magnetic structure bears a clear resemblance to oceanic crust, assumed to be related to the presence of ancient oceanic crust there.
基金supported by the National Natural Science Foundation of China(32272416,31972147)Project of Tianjin Science and Technology Plan(22ZYJDSS00030).
文摘Herein,a novel label-free electrochemical immunosensor was fabricated via immobilizing specific anti-β-lactoglobulin(β-LG)antibodies(Abs)onto an integrated electrode of gold nanoparticles(AuNPs)/Prussian blue(PB)/cubic Ia3d structured mesoporous carbon(CMK-8).This immunosensor allowed for the quantitative detection of the major milk allergenβ-LG.CMK-8 with excellent electrical conductivity and uniformly adjustable pore structure was modified on the glassy carbon electrode(GCE)and served as the sensitive substrate for the electro-polymerization of PB,forming the redox-active layer.AuNPs were subsequently electrochemically deposited on PB/CMK-8/GCE to improve the electrical conductivity and utilized as the connector for Abs immobilization.Duringβ-LG detection,the Abs-modified AuNPs/PB/CMK-8/GCE exhibited a significant reduction in differential pulse voltammetry current signal when exposed toβ-LG,displaying an inverse dose-dependent relationship.The developed electrochemical immunosensor demonstrated good detection performance forβ-LG,with a wider linear range of 0.01-100 ng/mL and a lower detection limit of 4.72 pg/mL.Meanwhile,the sensor exhibited remarkable repeatability,reproducibility,stability and anti-interference capabilities,which was further applied to detectβ-LG in dairy food,achieving satisfactory recoveries(89.2%-98.8%)and lower relative standard deviation(£3.1%).Therefore,this innovative electrochemical method for food allergen detection holds great potential application in food safety determination and evaluation.
基金supported by the National Key Research and Development Program of China(No.2021YFB4000405)National Natural Science Foundation of China(52270115,52236003,and 22109178)Science Foundation of China University of Petroleum Beijing(Nos.2462023YJRC032 and 2462023YJRC022).
文摘Producing hydrogen peroxide(H_(2)O_(2))through visible-light-driven photocatalytic oxygen reduction in pure water is crucial for sustainable ecological applications but poses significant challenges.It include the rapid recombination of electron-hole pairs and a scarcity of effective catalytic sites,which traditionally limit the process efficiency.To address these issues,we have developed a novel catalyst,designated as KCNOH,which consists of a three-dimensional(3D)porous g-C_(3)N_(4)framework doped with potassium(K^(+))and modified with surface hydroxyl groups(–OH).This design significantly enhances H_(2)O_(2)yield,achieving 91.36μmol g^(-1)h^(-1)(cut 420 nm)-a yield approximately 36 times higher than conventional bulk g-C_(3)N_(4)(2.57μmol g^(-1)h^(-1)).The introduction of a 3D porous structure provides an abundance of active-sites.The dual-dipole mechanism,facilitated by K^(+) ions and hydroxyl groups,plays a pivotal role by efficiently transporting photogenerated electrons and consuming holes,respectively.Through density functional theory(DFT)calculations,the changes in the band structure of the catalyst caused by the doping of K^(+) and the grafting of–OH were elucidated.In addition,the transition state affinity of oxygen induced by the–OH was also studied to reveal the synergistic catalytic mechanism.This mechanism markedly reduces carrier recombination and accelerates charge migration,underscoring its importance in catalyst design.Our findings not only improve the understanding of charge dynamics but also open novel perspectives for the design of highly-efficient composite materials,which is crucial for energy and environmental applications.
基金supported by the National Research Foundation of Korea(NRF)grants funded by the Korea government(MSIT)(Nos.RS-2024–00351052 and RS-2024–00450561)。
文摘Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.This study investigates the effects of Ti Cu precursor compositions on dealloying behavior and microstructural evolution in liquid Mg,using Ti_(50)Cu_(50)and Ti_(30)Cu_(70)precursors.The initial microstructure of the precursor significantly influences dealloying kinetics and phase transitions.The single-phase Ti_(50)Cu_(50)precursor exhibits a faster initial dealloying rate due to its homogeneous structure,yet complete dealloying requires 90 min.In contrast,the dualphase Ti_(30)Cu_(70)precursor achieves complete dealloying in 30 min,demonstrating the impact of a higher Cu concentration on accelerating the process kinetics.Additionally,the study explores the coarsening behavior and hardness variations during the LMD process,along with the microstructural characteristics of Mg-Ti composites fabricated from these two precursors.The findings highlight the critical role of precursor composition in tailoring the microstructure and properties of Mg-Ti composites produced through the LMD process,demonstrating its potential for advanced composite material manufacturing.
基金supported by the Leibniz-Forschungsinstitut für Molekulare Pharmakologie(FMP)and the Deutsche Forschungsgemeinschaft(DFG,German Research Foun-dation)under RTG 2473 Bioactive Peptides(392923329)A.F.K.and H.S.under Germany’s Excellence Strategy-EXC 2008/1(UniSysCat,390540038)to C.J.S.and H.S.+2 种基金the National Natural Science Foundation of China(U2006203)to B.-G.W.X.-L.Lsupport from the Taishan Scholars Program(tsqn202306366,China).A.N.-Vthanks National Council for Scien-tific and Technological Development(CNPq)for a research fellowship(309873/2023-1).
文摘Although anisotropic NMR spectroscopy has emerged as a powerful method for determining the relative configuration of complex natural products,major challenges persist with structurally flexible molecules.In this study,we conducted a system-atic comparative analysis of stereochemical elucidation,combining anisotropic NMR spectroscopy and density functional theory(DFT)calculations on spiroepicoccin B(1)and epicoccin V(2),which were characterized as thiodiketopiperazine marine natural products isolated from the deep-sea-derived fungus Epicoccum nigrum SD-388.For the flexible compound 2,we compared various conformational sampling approaches,including an assessment of the quality of relative energies within the obtained ensembles.We demonstrated the critical role of dispersion correction within DFT computations to precisely account for weak non-bonded intramolecular interactions.By integrating anisotropic NMR analysis,chemical shifts,elec-tronic circular dichroism,and DFT computations,we determined the absolute configurations and conformational ensembles for 1 and 2,respectively,highlighting the significance of the intramolecular methyl-πinteraction in stabilizing one of the conformers.Our study introduces new strategies to address conformational flexibility in the stereochemical elucidation of challenging organic molecules.
基金supported by the National Key R&D Program Project of China(No.2016YFC0600209)。
文摘The Nanling-Xuancheng ore region of Anhui Province is located in the Middle-Lower Yangtze River metallogenic belt.Insufficient exploration and research have been carried out in this newly defined ore district,although the Chating large porphyry Cu-Au deposit and a few middle-sized skarntype Cu polymetallic deposits have been discovered.In this study,we carried out high-resolution seismic reflection,magnetotelluric,gravity,and magnetic investigations,and constructed the 3 D geological structure of the uppermost crust in a depth range of 0-5 km using a comprehensive inversion of the new data constrained by previous deep-drilling data.We hence proposed some new insights to understand the mineralization processes of this district.A system of alternating ridges and valleys is suggested as the major structure pattern,composed of“two-layer structure”of the basins and“three-layer structure”of anticlines.Moreover,a conjugated fault system and its distribution features are revealed in our models,including the Jiangnan fault,Zhouwang fault,and Kunshan thrust nappe.The Jiangnan and Kunshan faults are suggested to have controlled the diagenesis and metallogenesis.Two deep concealed plutons located in Chating and Magushan are found,forming the Mesozoic diorite-felsic intrusions.These intrusions are believed to be the causes of hydrothermal deposits such as the Chating deposit and the Magushan deposit.
基金Project(2014CB239205)supported by the National Basic Research Program of ChinaProject(20011ZX05030-005-003)supported by the National Science and Technology Major Project of China
文摘Faults and fractures of multiple scales are frequently induced and generated in compressional structural system. Comprehensive identification of these potential faults and fractures that cannot be distinguished directly from seismic profile of the complex structures is still an unanswered problem. Based on the compressional structural geometry and kinematics theories as well as the structural interpretation from seismic data, a set of techniques is established for the identification of potential faults and fractures in compressional structures. Firstly, three-dimensional(3D) patterns and characteristics of the faults directly interpreted from seismic profile were illustrated by 3D structural model. Then, the unfolding index maps, the principal structural curvature maps, and tectonic stress field maps were obtained from structural restoration. Moreover, potential faults and fractures in compressional structures were quantitatively identified relying on comprehensive analysis of these three maps. Successful identification of the potential faults and fractures in Mishrif limestone formation and in Asmari dolomite formation of Buzurgan anticline in Iraq demonstrates the applicability and reliability of these techniques.
基金supported by China earthquake scientific array exploration Southern section of North South seismic belt(201008001)Northern section of North South seismic belt(20130811)+1 种基金National Natural Science Foundation of China(41474057)Science for Earthquake Resllience of China Earthquake Administration(XH15040Y)
文摘The special seismic tectonic environment and frequent seismicity in the southeastern margin of the Qinghai-Tibet Plateau show that this area is an ideal location to study the present tectonic movement and background of strong earthquakes in China's Mainland and to predict future strong earthquake risk zones. Studies of the structural environment and physical characteristics of the deep structure in this area are helpful to explore deep dynamic effects and deformation field characteristics, to strengthen our understanding of the roles of anisotropy and tectonic deformation and to study the deep tectonic background of the seismic origin of the block＇s interior. In this paper, the three-dimensional （3D） P-wave velocity structure of the crust and upper mantle under the southeastern margin of the Qinghai-Tibet Plateau is obtained via observational data from 224 permanent seismic stations in the regional digital seismic network of Yunnan and Sichuan Provinces and from 356 mobile China seismic arrays in the southern section of the north-south seismic belt using a joint inversion method of the regional earthquake and teleseismic data. The results indicate that the spatial distribution of the P-wave velocity anomalies in the shallow upper crust is closely related to the surface geological structure, terrain and lithology. Baoxing and Kangding, with their basic volcanic rocks and volcanic clastic rocks, present obvious high-velocity anomalies. The Chengdu Basin shows low-velocity anomalies associated with the Quaternary sediments. The Xichang Mesozoic Basin and the Butuo Basin are characterised by low- velocity anomalies related to very thick sedimentary layers. The upper and middle crust beneath the Chuan-Dian and Songpan-Ganzi Blocks has apparent lateral heterogeneities, including low-velocity zones of different sizes. There is a large range of low-velocity layers in the Songpan-Ganzi Block and the sub-block northwest of Sichuan Province, showing that the middle and lower crust is relatively weak. The Sichuan Basin, which is located in the western margin of the Yangtze platform, shows high-velocity characteristics. The results also reveal that there are continuous low-velocity layer distributions in the middle and lower crust of the Daliangshan Block and that the distribution direction of the low-velocity anomaly is nearly SN, which is consistent with the trend of the Daliangshan fault. The existence of the low-velocity layer in the crust also provides a deep source for the deep dynamic deformation and seismic activity of the Daliangshan Block and its boundary faults. The results of the 3D P-wave velocity structure show that an anomalous distribution of high-density, strong-magnetic and high-wave velocity exists inside the crust in the Panxi region. This is likely related to late Paleozoic mantle plume activity that led to a large number of mafic and ultra-mafic intrusions into the crust. In the crustal doming process, the massive intrusion of mantle-derived material enhanced the mechanical strength of the crustal medium. The P-wave velocity structure also revealed that the upper mantle contains a low-velocity layer at a depth of 80-120 km in the Panxi region. The existence of deep faults in the Panxi region, which provide conditions for transporting mantle thermal material into the crust, is the deep tectonic background for the area＇s strong earthquake activity.
基金provided by the Talent Training Project of the National Natural Science Foundation of China (No.J0730534)the National Natural Science Foundation of China (No.40902093)+1 种基金the Morning Light Plan of the Shanghai Educational Development Foundation (No.2007CG34)the Open Foundation of the Shanghai Key Laboratory of Urbanization and Ecological Restoration (No.200803)
文摘Uncertainty in 3D geological structure models has become a bottleneck that restricts the development and application of 3D geological modeling.In order to solve this problem during periods of accuracy assessment,error detection and dynamic correction in 3D geological structure models,we have reviewed the current situation and development trends in 3D geological modeling.The main context of uncertainty in 3D geological structure models is discussed.Major research issues and a general framework system of uncertainty in 3D geological structure models are proposed.We have described in detail the integration of development practices of 3D geological modeling systems,as well as the implementation process for uncertainty evaluation in 3D geological structure models.This study has laid the basis to build theoretical and methodological systems for accuracy assessment and error correction in 3D geological models and can assist in improving 3D modeling techniques under complex geological conditions.
