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Highly biased DNA sequence reconstruction in DNA storage with multi-scale attention mechanism and contrast learning 认领 引用
1
作者 Xue Li Yanfen Zheng +6 位作者 Qi Shao Jiadong Wang Wei Li Bin Wang Shihua Zhou Ben Cao Pan Zheng 《Synthetic and Systems Biotechnology》 SCIE CSCD 2026年第2期422-432,共11页
Base substitution,insertion,and deletion errors due to inherent technical constraints inducing unavoidable sequencing inaccuracies,limiting access to high-quality raw data and biological knowledge.To address this,we p... Base substitution,insertion,and deletion errors due to inherent technical constraints inducing unavoidable sequencing inaccuracies,limiting access to high-quality raw data and biological knowledge.To address this,we propose a deep sequence reconstruction model based on the multi-scale attention mechanism and contrastive learning(MACL),designed to enhance DNA sequence reconstruction under highly error rate conditions.The multi-scale attention mechanism includes base scale,inter-sequence and intra-sequence scale.First,the MSA Transformer fully extracts both global and local features of the base scale from the dimensions of the rows and columns.Furthermore,for the errors between sequences and the substitution errors within sequences,MACL proposes Inter-Sequence and Intra-Sequence Multi-Head Attention Mechanisms,respectively,and handles the insertion and deletion errors through the convolution module.In order to maximize the consistency of positive sample pairs in the representation space,we introduce contrastive learning and design a negative sample construction method and data augmentation that are more suitable for substitution errors in sequencing channels.Experiments on real-world DNA storage and viral genome datasets demonstrate that MACL significantly outperforms existing methods in reconstructing the DNA sequence.In particular,when combined with RS codes,MACL can losslessly reconstruct medical images in highly biased sequence(base error rate=5%)in DNA storage.In summary,the MACL introduces a novel approach to DNA sequence reconstruction in highly error rate conditions,laying a solid foundation for practical applications in DNA storage and genomics research. 展开更多
关键词 DNA sequence reconstruction DNA storage Noisy sequencing channels Multi-scale attention Contrast learning
Constructions of Control Sequence Set for Hierarchical Access in Data Link Network 认领 引用
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作者 Niu Xianhua Ma Jiabei +3 位作者 Zhou Enzhi Wang Yaoxuan Zeng Bosen Li Zhiping 《China Communications》 SCIE EI CSCD 2026年第1期67-80,共14页
As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and ... As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and diverse communication needs.It is crucial to design control sequences with robust randomness and conflict-freeness to properly address differentiated access control in data link.In this paper,we propose a hierarchical access control scheme based on control sequences to achieve high utilization of time slots and differentiated access control.A theoretical bound of the hierarchical control sequence set is derived to characterize the constraints on the parameters of the sequence set.Moreover,two classes of optimal hierarchical control sequence sets satisfying the theoretical bound are constructed,both of which enable the scheme to achieve maximum utilization of time slots.Compared with the fixed time slot allocation scheme,our scheme reduces the symbol error rate by up to 9%,which indicates a significant improvement in anti-interference and eavesdropping capabilities. 展开更多
关键词 control sequence data link hierarchical access control theoretical bound
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Mitochondrial Control Region Sequence-Based Population Genetic Analysis of Charybdis japonica Specimens Collected from the Chinese Inshore Waters 认领 引用
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作者 SUN Shaolei HE Jingjing +1 位作者 TANG Kelin HAN Zhiqiang 《Journal of Ocean University of China》 SCIE CAS CSCD 2026年第4期1480-1488,I0063,共9页
The Asian paddle crab,Charybdis japonica,is a commercially and ecologically important marine species.Discerning the population genetic structure and connectivity of C.japonica in a dynamic marine environment is crucia... The Asian paddle crab,Charybdis japonica,is a commercially and ecologically important marine species.Discerning the population genetic structure and connectivity of C.japonica in a dynamic marine environment is crucial for implementing sustainable management practices.This study investigated the population genetics of C.japonica in the Bohai,Yellow,and East China Seas using 104 mtDNA control-region sequences;a total of 26 haplotypes were identified.High haplotype but low nucleotide diversity were detected among five populations.The frequency of the dominant haplotype H4 declined along the Chinese coast from the southern regions(Taizhou and Zhoushan)to the northern regions(Lianyungang,Yantai,and Dalian).The relatively abundant H1 haplotype exhibited a higher localized frequency in the south than in the north.A Neighbor-Joining phylogenetic tree was constructed from these sequences;two distinct lineages(A and B)with remarkable differences in their geographic distribution frequencies were detected.The proportion of lineage A individuals declined along the Chinese coast from south to north,and lineage B members were mainly found in the Dalian population.AMOVA and pairwise FST values showed statistically significant genetic differences among five populations,with the Dalian population differing most from the other four.The Mantel test results indicated that coastal distance may hinder gene flow between Dalian and the other four populations.Thus,our results suggest that five C.japonica populations along the Chinese coast can be considered separate fishery management units.These findings can help guide the design of future C.japonica management practices applicable to this region of China’s coastal waters. 展开更多
关键词 Charybdis japonica population genetics genetic structure gene flow control region sequence
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Sedimentary Characteristics and Evolution of the High-resolution Sequence Stratigraphic Framework of the Taiyuan Formation in the Hangjinqi Area,Northern Ordos Basin 认领 引用
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作者 ZHAO Mingsheng TIAN Jingchun +1 位作者 SU Bingrui ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2026年第1期54-68,共15页
The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theor... The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theoretical and practical significance for guiding oil and gas exploration.The sedimentary facies and sedimentary evolution of the high-resolution sequence framework of the Carboniferous Taiyuan Formation in the Hangjinqi area have been systematically analyzed for the first time by drilling,logging and seismic data.The results show that four types of sequence interfaces can be identified in the Taiyuan Formation:regional unconformity surfaces,scour surfaces,lithologic-lithofacies transformation surfaces and flooding surfaces.According to the sedimentary response caused by the upward and downward movements of the base level at different levels,the Taiyuan Formation can be divided into 2 long-term cycles(LSC1-LSC2),4 mid-term cycles(MSC1-MSC4)and 7 short-term cycles(SSC1-SSC7).The long-and mid-term cycles correspond to members T1and T2and layers T1-1,T1-2,T2-1,and T2-2,respectively.Long-term cycles are dominated by C1;mid-term cycles are dominated by C1and C2,followed by A2;and short-term cycles are dominated by C1,C2,A1 and A2.Under the high-resolution sequence stratigraphic framework,the Hangjinqi area underwent a transformation of fan delta and tidal flat depositional systems during the Taiyuan Formation sedimentary period.In the MSC1-MSC2stage,owing to a large-scale paleocontinent,the fan delta sedimentary body,which was limited in scale and scope,developed only in the southeastern corner and gradually transitioned basinward to tidal flat facies.In the MSC3-MSC4 stage,as the paleocontinent continuously decreased and the sedimentary range expanded,fan-delta plain sedimentation began in the study area.Several braided distributary channels with poor connectivity developed on the fan-delta plain,and between them were floodplains and peat swamps. 展开更多
关键词 high-resolution sequence framework sedimentary characteristics sedimentary evolution Taiyuan Formation Hangjinqi area northern Ordos Basin
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MEAN LI-YORKE CHAOS FOR A SEQUENCE OF OPERATORS ON BANACH SPACES 认领 引用
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作者 Jian LI Xinsheng WANG Jianjie ZHAO 《Acta Mathematica Scientia》 SCIE CSCD 2026年第3期1187-1207,共21页
In this paper,we obtain the dichotomy between mean equicontinuity and mean sensitivity for a sequence of bounded linear operators from a Banach space to a normed linear space.The mean Li-Yorke chaos for sequences and ... In this paper,we obtain the dichotomy between mean equicontinuity and mean sensitivity for a sequence of bounded linear operators from a Banach space to a normed linear space.The mean Li-Yorke chaos for sequences and submultiplicative sequences of bounded linear operators are also studied.Furthermore,several criteria for mean Li-Yorke chaos are established. 展开更多
关键词 linear operator mean Li-Yorke chaos absolutely mean irregular vector mean equicontinuity mean sensitivity submultiplicative sequence
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Genetic diversity and population structure of the Fujian oyster Crassostrea angulata revealed by mitochondrial COI gene and nuclear gene ITS2 sequences 认领 引用
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作者 Shiqi YU Ziqiang HAN Huayong QUE 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2026年第1期419-432,共14页
The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The mai... The Fujian oyster(Crassostrea angulata) is an economically significant shellfish species distributed mainly along the Fujian coast, Southeast China. However, its genetic diversity and structure remain unclear. The main distribution area of the C. angulata is located in Fujian, South China. In total, 420 C. angulata were collected from 14 natural habitats(populations) along the Fujian coast, and their genetic diversity and structure were analyzed in the mitochondrial COI and nuclear gene ITS2 sequences. Results reveal that all the 14 populations of C. angulata exhibited high levels of genetic diversity, with a total of 57(haplotype diversity: 0.811±0.016) and 124(haplotype diversity: 0.912±0.007) haplotypes revealed by COI and ITS2, respectively. Notably, significant intermediate level of genetic differentiations between the Ningde Zhujiang(ZJ) population(FS T by COI: 0.035–0.142, P<0.05;FS T by ITS2: 0.078–0.123, P<0.05) with other populations were observed for the first time, which is also supported by the results of molecular variance analysis(FC T by COI: 0.105, P<0.05;FC T by ITS2: 0.086, P<0.05) and the clustering of the ZJ population into distinct branches in the interpopulation genetic differentiation tree. Furthermore, the evolutionary tree and haplotype network analyses do not support the formation of a clear geographical genealogical structure among these 14 populations. In addition, the population dynamics analysis suggests that the C. angulata may have undergone expansion during the third ice age of the Pleistocene. These results provide a reference for the preservation and further genetic improvement of C. angulata. 展开更多
关键词 Crassostrea angulata genetic diversity population structure mitochondrial COⅠgene nuclear gene ITS2 sequence
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Crystallization-sequence engineering enables organic solar cell modules with efficiencies exceeding 18% 认领 引用
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作者 Yunhao Cai Hui Huang 《Journal of Semiconductors》 EI CAS CSCD 2026年第6期25-28,共4页
Organic solar cells(OSCs)have emerged as a promising photovoltaic technology owing to their intrinsic advantages of mechanical flexibility,low density,and compatibility with solution-based fabrication[1].These feature... Organic solar cells(OSCs)have emerged as a promising photovoltaic technology owing to their intrinsic advantages of mechanical flexibility,low density,and compatibility with solution-based fabrication[1].These features enable applications that are difficult to realize with rigid inorganic counterparts,including wearable electronics,portable energy systems,curved or lightweight structures,and building-integrated photovoltaics.Moreover,OSCs can be manufactured using scalable coating and printing techniques at relatively low temperatures,offering the prospect of high-throughput and cost-effective production.Despite the rapid increase in laboratory efficiencies over the past decade[2−4],transferring these advances to large-area modules remains a significant challenge. 展开更多
关键词 efficiencies mechanical flexibility photovoltaic technology crystallization sequence engineering organic solar cells low density organic solar cells oscs printing techniques
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Higher-Order Expansions of Powered Order Statistics of Maxwell Sequences 认领 引用
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作者 HUANG Jian-wen LIU Xin-ling +1 位作者 JIA Jin-ping WANG Run-ke 《Chinese Quarterly Journal of Mathematics》 2026年第2期162-173,共12页
Under the optimal norming constants, this paper studies the higher-order expansions of the distributions and densities of the powered order statistics of Maxwell sequence. As auxiliary results, the corresponding conve... Under the optimal norming constants, this paper studies the higher-order expansions of the distributions and densities of the powered order statistics of Maxwell sequence. As auxiliary results, the corresponding convergence rates are obtained. The results show that the convergence rates of distributions and densities of normalized power order statistics are related to power index in principle. Finally, we compared the accuracy of each approximations with its true values through numerical experiments. 展开更多
关键词 Maxwell sequences Powered order statistics Higher-order expansion Convergence rate
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Stochastic discrete event simulation for government assisted owner driven participatory housing recovery modeling:Application to 2015 Gorkha earthquake sequence,Nepal 认领 引用
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作者 Dipendra Gautam Sajan KC Olafur Petur Palsson 《Resilient Cities and Structures》 EI CSCD 2026年第1期45-59,共15页
We develop and implement a Stochastic Discrete Event Simulation(SDES)algorithm to model the housing re-covery trajectory after an extreme event.The algorithm models discrete events and their underlying uncertainties i... We develop and implement a Stochastic Discrete Event Simulation(SDES)algorithm to model the housing re-covery trajectory after an extreme event.The algorithm models discrete events and their underlying uncertainties in each construction phase.Specifically,the algorithm is developed for the Government Assisted Owner Driven(GAOD)reconstruction system to simulate long-term recovery trajectory.SDES,as a flexible modeling approach,can simulate any housing recovery scenario that follows phased reconstruction.The 2015 M 7.8 Gorkha earthquake sequence in Nepal is considered the extreme event,with 796,245 buildings requiring reconstruction.We present some recovery trajectories from severely hit,crisis hit,and earthquake hit parishes,comparing them with the actual reconstruction progress.We also assess quality and improvement of reconstructed buildings using seismic fragility functions,compared to pre-earthquake constructions.Housing recovery uncertainties are dissected in relation to reconstruction pace.We conclude that the vast majority of the reconstructed buildings followed the Build Back Better(BBB)approach and missed the opportunity to pursue the Build Back Resilient(BBR)approach due to multifaceted challenges ranging from unclear policies to economic constraints.We critically assess the GAOD vs Owner Driven(OD)recovery framework and conclude that insurance-supported and technically assisted OD approach could be the most suitable model for post extreme event housing recovery. 展开更多
关键词 Stochastic modeling Discrete event simulation Participatory reconstruction Housing recovery Community resilience Earthquake damage Reinforced concrete Stone masonry Brick masonry Seismic vulnerability Gorkha earthquake sequence
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Synergistic integration of ancestral sequence reconstruction and rational design empowers unspecific peroxygenase for efficient steroid core oxyfunctionalization 认领 引用
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作者 Ruiwen Hu Zhiyong Guo +5 位作者 Xiaogang Peng Xiaoqi Shi Yuben Qiao Qian Li Chenghua Gao Aitao Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2026年第5期417-427,共11页
Unspecific peroxygenases(UPOs)are versatile biocatalysts for selective oxyfunctionalization,yet their use in steroid core hydroxylation remains underdeveloped.Although CglUPO is the best-studied steroid-hydroxylating ... Unspecific peroxygenases(UPOs)are versatile biocatalysts for selective oxyfunctionalization,yet their use in steroid core hydroxylation remains underdeveloped.Although CglUPO is the best-studied steroid-hydroxylating UPO,its inefficiency and tendency to form unwanted epoxides limit its practicality.To overcome this,we employed ancestral sequence reconstruction(ASR)to obtain ancestral UPO N1 that exhibited 3-fold higher expression than modern counterparts CglUPO and demonstrated moderate regioselectivity(63%)for 11β-hydroxylation of estra-4,9-diene-3,17-dione(1).Guided by molecular dynamics simulations,rational mutagenesis of key substrate-binding residues generated the variant N1-F83G/L232V.This variant achieved a 36-fold increase in catalytic activity with near-complete 11β-regioselectivity(99%).Mechanistic study revealed that L232V reduces steric hindrance near the active site,while F83G eliminates a mispositioned hydrophobic anchor—challenging the paradigm that hydrophobic interactions always benefit catalysis.Substrate scope studies confimred the broad applicability of this variant,yielding different hydroxylation patterns(11β-,16α-,6β-)depending on steroids tested.Gram-scale synthesis afforded isolated yields of 40~86%for different hydroxylated steriods,which serve as pivotal intermediates for synthesizing desogestrel,estriol,and exemestane.Overall,this work advances the steroid biocatalysis toolbox,demonstrates how integraing ASR with rational engineering solves UPO limitations,and establishes UPOs as industrially viable catalysts for steroid pharmaceutical synthesis. 展开更多
关键词 Steroid hydroxylation Unspecific peroxygenases Acestral sequence reconstruction Regioselectivity
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Effect of Nb,Ti introduction sequence on adsorption of Nb on TiB2 surface and grain refinement performance of Al-4Ti-1Nb-1B 认领 引用
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作者 Hao Yi Ying Cheng +1 位作者 Hua-rui Zhang Hu Zhang 《China Foundry》 SCIE EI CAS CSCD 2026年第3期357-366,共10页
In recent years,Al-Ti-Nb-B grain refiners have attracted increasing attention due to their grain refinement performance and anti-Si poisoning ability.This study investigates the influence of the introduction sequence ... In recent years,Al-Ti-Nb-B grain refiners have attracted increasing attention due to their grain refinement performance and anti-Si poisoning ability.This study investigates the influence of the introduction sequence of Ti and Nb during the synthesis of Al-4Ti-1Nb-1B refiners on their refinement performance on CP-Al and a series of Al-Si alloys(Al-3.5Si,Al-7Si,and Al-10.5Si).It is found that Al-4Ti-1Nb-1B prepared by introducing Ti prior to Nb exhibits the best grain refinement and anti-Si poisoning compared to samples where Nb is introduced before Ti or where both are added simultaneously.This Ti-first approach demonstrates superior grain refinement performance across CP-Al,Al-3.5S1,Ai-7Si,and Al-10.5Si alloys,especially at higher Si contents.It refines the grain size of Al-7Si to 150.1±27.5μm from over 1,500μm for the unrefined alloy.This superior performance is attributed to the variation in ground-state energy ΔE for the Ti prior to Nb sequence is lower than that of other sequences,thereby facilitating Nb adsorption on the TiB2 surface.TEM observations corroborate these findings,showing that TiB2 prepared by this sequence has the highest average Nb content of 3.80at.%.First-principles calculations reveal that this unique Nb adsorption enhances the TiB2/Al interfacial adhesion energy Wa d and suppresses the segregation tendency of Si atoms at the interface,κSi(cSi).The higher the Nb adsorption at the TiB2/Al interface,the stronger the resistance to Si poisoning.These findings underscore the pivotal role of Nb-modified TiB2 in improving grain refinement and offer a novel strategy for advancing grain refiner technologies in Al-Si alloys. 展开更多
关键词 introduction sequence grain refinement Nb adsorption nucleation mechanism
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Eyebrow damage control for ring blasting based on detonation sequence optimization 认领 引用
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作者 WEI Wenpeng DENG Guiyuan +4 位作者 WU Yonghong HUO Xiaofeng LIU Jie FENG Yujun XIAN Liangming 《Journal of Mountain Science》 SCIE CSCD 2026年第4期1834-1849,共16页
Brow damage control in ring blasting is essential for ensuring roof stability in mining roadways.However,previous studies have largely focused on rock fragmentation at the borehole bottom,with limited attention to cra... Brow damage control in ring blasting is essential for ensuring roof stability in mining roadways.However,previous studies have largely focused on rock fragmentation at the borehole bottom,with limited attention to cracks near the collar.This study investigates brow damage mitigation through optimization of the detonation sequence.The damage mechanism was first analyzed theoretically based on stress field distribution.Numerical simulations of ring blasting under different detonation sequences were then performed using ANSYS/LS-DYNA,followed by field validation of the findings.Results indicate that the stress field end effect along the detonation direction depends on both detonation distance and the number of simultaneously initiated holes.Simultaneous initiation of multiple holes creates a splitting effect between ring holes,isolating the blasting zone from the surrounding rock and reducing damage to the reserved rock.In delayed detonation,damage induced by earlier-initiated holes guides the damage propagation of subsequent blastholes.Optimal brow damage control was achieved by initiating the central three holes first,followed by the side holes,and field tests confirmed that it significantly improves brow integrity.This study provides practical guidance for enhancing brow integrity and safety protocols in roadway ring blasting. 展开更多
关键词 Rock blasting Detonation sequence Stress field distribution Eyebrow damage Numerical simulation
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Generalized Euler-Riesz difference sequence space with a paranormed fractional ordered µ 认领 引用
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作者 Munevver Tuz Cigdem Asma Bektas 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2026年第1期214-224,共11页
In this study,we introduce the sequence space lμ(p,Δm) with a fractional order μ.Furthermore,we give some topological properties of this space.Also we introduce α-,β-,andγ-duals of lμ(p,Δm) and its... In this study,we introduce the sequence space lμ(p,Δm) with a fractional order μ.Furthermore,we give some topological properties of this space.Also we introduce α-,β-,andγ-duals of lμ(p,Δm) and its some matrix mappings. 展开更多
关键词 Euler-Riesz sequence space difference sequence space paranorm α-β-andγ-duals matrix transformations
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Effects of phosphate/silicate electrolytes and oxidation sequence on the corrosion resistance,cytotoxicity,and osteogenic property of micro-arc oxidation coating on magnesium alloy as GBR membrane 认领 引用
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作者 Shen WEN Ling +5 位作者 LI Ze-ren HUANG Jie-wen KOLAWOLE Sharafadeen Kunle SIDDIQUI Muhammad Ali CHEN Jun-xiu SHAN Xian-feng 《Journal of Central South University》 SCIE EI CAS CSCD 2026年第2期599-615,共17页
In order to further improve the degradation resistance and osteogenic property of the micro arc oxidation(MAO)coating of Mg alloys,the Mg alloy samples were oxidized in phosphate electrolyte,silicate electrolyte,first... In order to further improve the degradation resistance and osteogenic property of the micro arc oxidation(MAO)coating of Mg alloys,the Mg alloy samples were oxidized in phosphate electrolyte,silicate electrolyte,first phosphate electrolyte+second silicate electrolyte,and first silicate electrolyte+second phosphate electrolyte.And the corrosion resistance,cytotoxicity,and osteogenic property of the samples were studied.The results showed that the Na2SiO3-MAO coated sample had more micropores than the CaP-MAO coated sample.The composite micro-arc oxidation(MAO)coatings obviously improved the degradation resistance of the alloy.Moreover,the samples fabricated first in silicate electrolyte and then in phosphate electrolyte showed the best corrosion resistance with the corrosion current density of only 0.1μA/cm2,which was two orders of magnitude lower than the single silicate Na2SiO3-MAO coated(10.9μA/cm2).Besides,the cytocompatibility of the MAO coated samples was good,presenting no cell toxicity.The extract from the Na2SiO3+CaP coated sample promoted cell proliferation,reaching almost 100%after 5 d.Na2SiO3+CaP coated sample showed the best osteogenic property with bone volumeotal volume(BV/TV)about 55%after 8 weeks implantation in calvarial region(parietal bone)of the skull.The results indicated that the Na2SiO3+CaP coated magnesium alloy exhibited the best corrosion resistance and osteogenic property. 展开更多
关键词 micro arc oxidation oxidation sequence corrosion resistance osteogenic property guided bone regeneration(GBR)membrane
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Robust Hyper-Polarization Protocol of Nuclear Spins via Magic Sequence 认领 引用
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作者 Haiyang Li Yongju Li +1 位作者 Hao Liao Ping Wang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2026年第1期105-128,共24页
Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to thei... Hyperpolarization of nuclear spins is crucial for advancing nuclear magnetic resonance and quantum information technologies,as nuclear spins typically exhibit extremely low polarization at room temperature due to their small gyromagnetic ratios.A promising approach to achieving high nuclear spin polarization is transferring the polarization of electrons to nuclear spins.The nitrogen-vacancy(NV)center in diamond has emerged as a highly effective medium for this purpose,and various hyperpolarization protocols have been developed.Among these,the pulsed polarization(PulsePol)method has been extensively studied due to its robustness against static energy shifts of the electron spin.In this work,we present a novel polarization protocol and uncover a family of magic sequences for hyperpolarizing nuclear spins,with PulsePol emerging as a special case of our general approach.Notably,we demonstrate that some of these magic sequences exhibit significantly greater robustness compared to the PulsePol protocol in the presence of finite halfpulse duration of the protocol,Rabi and detuning errors.This enhanced robustness positions our protocol as a more suitable candidate for hyper-polarizing nuclear spins species with large gyromagnetic ratios and also ensures better compatibility with high-efficiency readout techniques at high magnetic fields.Additionally,the generality of our protocol allows for its direct application to other solid-state quantum systems beyond the NV center. 展开更多
关键词 transferring polarization electrons hyperpolarization protocols quantum information technologiesas nuclear spins pulse polarization nuclear spin polarization magic sequences nuclear magnetic resonance
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Seismic Response of Offshore Reinforced Concrete Bridges Under Main-Aftershock Sequences 认领 引用
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作者 CAO Jing LI Yue +1 位作者 ZHANG Changyong LI Chong 《吉首大学学报（自然科学版）》 CAS 2026年第2期62-71,共10页
To investigate the seismic response evolution of offshore bridges under the coupled effects of main-aftershock sequences and chloride-induced erosion,a time-dependent damage finite element model of a three-span,three-... To investigate the seismic response evolution of offshore bridges under the coupled effects of main-aftershock sequences and chloride-induced erosion,a time-dependent damage finite element model of a three-span,three-column simply supported bridge was established based on energy dissipation theory and static pushover analysis.Seismic time-history analysis was conducted to obtain key response indicators,including the maximum displacement and residual displacement at the pier top,as well as the proportion of cumulative hysteretic energy generated at the pier bottom during aftershocks.The results show that structural durability degradation significantly affected the seismic responses:under the same seismic excitation,the maximum pier-top displacement of long-term service bridges increased by at least 10%,with a maximum increase of up to 43%,compared with newly built bridges.When subjected to high-intensity earthquakes,the residual displacement at the pier top continuously increased with service time,rising by 66%,121%,and 163%after 50,75,and 100 a of service,respectively,compared with new bridges.Aftershocks induced noticeable cumulative damage at critical locations such as the pier bottom,with the cumulative hysteretic energy accounting for an average of 14.08%of the total energy dissipation during the main-aftershock sequence,reaching a maximum of 25.3%.Therefore,it is recommended that both the energy contribution of aftershocks and the effect of durability degradation be considered in the seismic design of offshore bridges. 展开更多
关键词 main-aftershock sequences chloride ion erosion simply-supported bridge maximum displacement residual displacement hysteresis curve
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Effects of welding sequences and filler metals on microstructure and mechanical properties of N08825/L360 nickel-based alloy clad plate welded joints 认领 引用
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作者 ZHU Min 《Baosteel Technical Research》 CAS 2026年第2期33-46,共14页
Nickel-based alloy clad plate(NACP)is a promising composite structural material owing to its excellent mechanical and corrosion-resistant properties,as well as its low cost.However,the development of welding technolog... Nickel-based alloy clad plate(NACP)is a promising composite structural material owing to its excellent mechanical and corrosion-resistant properties,as well as its low cost.However,the development of welding technology for NACP has lagged behind.Herein,N08825/L360 NACP was used as the model material,and welded joints were prepared using tungsten inert gas welding to investigate the effects of different welding sequences and filler metals on the micro structure and mechanical properties of joints.The results showed that weld seams filled with mixed filler metals under the post-flyer welding seam welding sequence exhibited a uniform micro structure,and the joints performed well in tensile,bending,and impact tests.For joints filled with mixed filler metals under the post-base welding seam sequence(P-BWS)satisfactory face-bending,root-bending,and tensile properties were achieved;however,cracks formed in the side-bending specimens,and the impact toughness decreased greatly.Micro structural analysis shows that the deterioration in weld toughness is attributable to two factors:severe dimensional embrittlement and micro structural embrittlement,both caused by the formation of hardened welds in the welding seam.Under the P-BWS,using only nickel-based alloy filler metals effectively prevents the deterioration of the micro structure and properties of welding seams. 展开更多
关键词 N08825/L360 nickel-based alloy clad plate welding sequence welding filler metals microstructure mechanical property
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On Extremal Trees with Given Degree Sequence for ABS Index 认领 引用
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作者 LI Fengwei YE Qingfang 《数学进展》 CSCD 北大核心 2026年第3期567-577,共11页
The atom-bond sum-connectivity(ABS)index of a graph G=(V,E)is defined as■,where d(ζ)represents the degree of vertexζ∈V.By using ABS index,the heat of formation of octane and heptane can be accurately predicted.The... The atom-bond sum-connectivity(ABS)index of a graph G=(V,E)is defined as■,where d(ζ)represents the degree of vertexζ∈V.By using ABS index,the heat of formation of octane and heptane can be accurately predicted.The extremal trees with fixed degree sequences that maximize or minimize the ABS index are characterized in this paper.Meanwhile,we offer construction algorithms for these kinds of trees. 展开更多
关键词 topological index ABS index tree degree sequence extremal graph
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New Asymptotically Optimal Periodic Quasi-complementary Sequence Sets with Small Alphabet Sizes from Permutation Polynomials 认领 引用
19
作者 LIU Ruoxi WANG Yan WU Chenhuang 《数学进展》 CSCD 北大核心 2026年第4期938-954,共17页
Designing quasi-complementary sequence sets(QCSSs)with parameters that balance low periodic maximum correlation magnitude,large set size,and small alphabet size is an essential objective in multi-carrier code-division... Designing quasi-complementary sequence sets(QCSSs)with parameters that balance low periodic maximum correlation magnitude,large set size,and small alphabet size is an essential objective in multi-carrier code-division multiple-access(MC-CDMA).This paper proposed novel methods for constructing periodic QCSSs using permutation polynomials and difference sets over finite fields.By evaluating certain exponential sums,we establish that the proposed periodic QCSSs possess both large set sizes and small alphabet sizes.Furthermore,computational MAGMA program experiments demonstrate that our constructions can yield numerous asymptotically optimal periodic QCSSs. 展开更多
关键词 quasi-complementary sequence set asymptotically optimal permutation polynomial multi-carrier code-division multiple-access
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A New Construction of Stefan’s Homological Spectral Sequence 认领 引用
20
作者 LIU Li-yu 《Chinese Quarterly Journal of Mathematics》 2026年第1期60-67,共8页
In this paper,we offer a new construction of Stefan’s homological spectral sequence for Hopf Galois extensions,by using the double complex argument.Under the faithfully flat condition,a method for computation of Hoch... In this paper,we offer a new construction of Stefan’s homological spectral sequence for Hopf Galois extensions,by using the double complex argument.Under the faithfully flat condition,a method for computation of Hochschild homology is given. 展开更多
关键词 Hopf algebra Hopf Galois extension Spectral sequence Hochschild homology
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