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Amorphous Sb/C composite with isotropic expansion property as an ultra-stable and high-rate anode for lithium-ion batteries

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Rare Metals 2024年第5期43卷 2039-2052页

作者： Ze-Zhou Yang Cheng-Yi Zhang Yu-Qing Ou Zhi-Kang su Yan Zhao Heng-Jiang Cong Xin-ping Ai Jiang-Feng Qian Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular SciencesWuhan UniversityWuhan430072China Institute of Technological Sciences Wuhan UniversityWuhan 430072China

Antimony(Sb)is an intriguing anode material for Li-ion batteries(LIBs)owing to its high theoretical capacity of 660 m Ah·g^(-1)and appropriate working potential of~0.8 V(***^(+)/Li).However,just like all alloying materials,the Sb anode suffers from huge volume expansion(230%)during repeated insertion/extraction of Li+ions,resulting in structural deterioration and rapid capacity *** this work,a novel amorphous Sb/C composite with atomically dispersed Sb particles in carbon matrix is prepared via a straightforward high-energy ball milling *** intimate intermixing of amorphous Sb with C provides homogeneous element distribution and isotropic volume expansion during cycling,resulting in persistent structural ***,the disordered structure of amorphous material shortens the diffusion distance of lithium ions/electrons,promoting fast reaction kinetics and rate *** from the aforementioned effects,the amorphous Sb/C exhibits a high reversible capacity of537.4 m Ah·g^(-1)at 0.1 A·g^(-1)and retains 201.0 m Ah·g^(-1)at an ultrahigh current rate of 10.0 A·g^(-1).Even after 1500deep cycles at 2.0 A·g^(-1),the amorphous Sb/C electrode still maintains 86.3%of its initial capacity,which outperforms all existing Sb-based anodes reported so *** analysis further reveals a greatly reduced volume variation of merely 34.6%for the amorphous Sb/C electrode,much lower than that of 223.1%for crystalline Sb *** study presents a new approach to stabilizing Sb-based alloy anodes and contributes to the construction of high-performance amorphous anode materials for LIBs,enabling advanced energy storage.

关键词： Amorphous Sb/C anode Homogeneous element distribution Isotropic volume expansion Ultra-long cycle stability High-rate capability Lithium-ion battery

Shock Formation for 2D Isentropic Euler Equations with Self-similar Variables

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 349-412页

作者： Wenze su School of Mathematical Sciences Fudan UniversityShanghai 200433China

The author studies the 2D isentropic Euler equations with the ideal gas *** exhibits a set of smooth initial data that give rise to shock formation at a single point near the planar *** solutions to the 2D isentropic Euler equations are associated with non-zero vorticity at the shock and have uniform-in-time-1/3-Holder ***,these point shocks are of self-similar type and share the same profile,which is a solution to the 2D self-similar Burgers *** proof of the solutions,following the 3D construction of Buckmaster,Shkoller and Vicol(in 2023),is based on the stable 2D self-similar Burgers profile and the modulation method.

关键词： 2D isentropic Euler equations Shock formation Self-similar solution

Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

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Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： CHEN Chen QUAN Wei shao Zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced ***, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)

BSAlign:A Library for Nucleotide Sequence Alignment

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 135-142页

作者： Haojing shao Jue Ruan Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China

Increasing the accuracy of the nucleotide sequence alignment is an essential issue in genomics *** classic dynamic programming(DP)algorithms(e.g.,Smith–Waterman and Needleman–Wunsch)guarantee to produce the optimal result,their time complexity hinders the application of large-scale sequence *** optimization efforts that aim to accelerate the alignment process generally come from three perspectives:redesigning data structures[e.g.,diagonal or striped Single Instruction Multiple Data(SIMD)implementations],increasing the number of parallelisms in SIMD operations(e.g.,difference recurrence relation),or reducing search space(e.g.,banded DP).However,no methods combine all these three aspects to build an ultra-fast *** this study,we developed a Banded Striped Aligner(BSAlign)library that delivers accurate alignment results at an ultra-fast speed by knitting a series of novel methods together to take advantage of all of the aforementioned three perspectives with highlights such as active F-loop in striped vectorization and striped move in banded *** applied our new acceleration design on both regular and edit distance pairwise *** achieved 2-fold speed-up than other SIMD-based implementations for regular pairwise alignment,and 1.5-fold to 4-fold speed-up in edit distance-based implementations for long *** is implemented in C programing language and is available at https://***/ruanjue/bsalign.

关键词： Pairwise alignment Edit distance Striped vectorization Banded dynamic programming F evaluation

青藏高原地表土壤重金属元素组成分布特征及其影响因素研究

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中国环境科学 2024年第4期44卷 2198-2207页

作者：刘小莉高文华魏婷董志文 shao Ya-ping 河南大学地理与环境学院国家级实验教学示范中心河南开封475000 中国地质大学地理与信息工程学院湖北武汉430074 中国科学院西北生态环境资源研究院甘肃兰州730000 德国科隆大学地球物理与气象研究所德国科隆50923

由于青藏高原生态系统的脆弱性和对人类活动的敏感性,近年来高原环境中与人类活动相关的重金属污染研究受到越来越多的关注.本文通过2021~2022年间采集的青藏高原表土样品,结合同时期采集的周边高海拔冰川区雪冰样品,分析测定了As、Cr... 详细信息

由于青藏高原生态系统的脆弱性和对人类活动的敏感性,近年来高原环境中与人类活动相关的重金属污染研究受到越来越多的关注.本文通过2021~2022年间采集的青藏高原表土样品,结合同时期采集的周边高海拔冰川区雪冰样品,分析测定了As、Cr、Co、Ni、Cu、Mo、Cd、Pb和Sb共9种重金属元素的含量和组成特征.结果表明,青藏高原表土中重金属的含量(均值为256.5μg/g)远高于雪冰中重金属(均值为14.6μg/L)的含量.其中As的I geo平均值为1.32,总体处于中度污染水平,而土壤中其他重金属以无污染特征为主.表土中重金属的组成和空间分布与周边冰川区雪冰中表现出明显不同特征,而且不同区域表土重金属的空间分布、组成和富集系数(EFs)没有明显差别.结合相关性、主成分分析和APCS-MLR等方法,发现表土中重金属有3个主要来源,分别为居民生活和工业用煤有关的煤燃烧源(42.3%)、局地地表自生土壤来源(20.6%)和交通排放源(14.2%).高海拔雪冰和表土中重金属的组成、分布存在差异,可能是由于地表样品中重金属受到自然风化、和人类活动影响导致远距离输入源的贡献被掩盖,而雪冰中重金属则更多受到大气环流远距离输入污染源的影响.本研究较为全面的展示了目前青藏高原大范围区域表土中重金属组成状况,反映出部分元素的明显富集(例如As)和整体上重金属元素含量仍然表现为清洁的自然状况.

关键词：重金属元素地表土壤青藏高原组成特征源解析

Novel variants in DNAH6 cause male infertility associated with multiple morphological abnormalities of the sperm flagella(MMAF)and ICSI outcomes

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Asian Journal of Andrology 2024年第1期26卷 91-98页

作者： Zhong-Mei shao Yu-Tong Zhu Meng Gu Sen-Chao Guo Hui Yu Kuo-Kuo Li Dong-Dong Tang Yu-ping Xu Ming-Rong Lv Reproductive Medicine Center Department of Obstetrics and Gynecologythe First Affiliated Hospital of Anhui Medical UniversityHefei 230022China Department of Obstetrics and Gynecology Fuyang Hospital of Anhui Medical UniversityFuyang 236112China NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract(Anhui Medical University) Hefei 230032China Key Laboratory of Population Health Across Life Cycle(Anhui Medical University) Ministry of Education of the People'sRepublicof ChinaHefei 230032China

Variations in the dynein axonemal heavy chain gene,dynein axonemal heavy chain 6(DNAH6),lead to multiple morphological abnormalities of the *** studies have reported that these deficiencies may result in sperm head ***,whether DNAH6 is also involved in human acrosome biogenesis remains *** purpose of this study was to investigate DNAH6 gene variants and their potential functions in the formation of defective sperm heads and ***-exome sequencing was performed on a cohort of 375 patients with asthenoteratozoospermia from the First Affiliated Hospital of Anhui Medical University(Hefei,China).Hematoxylin and eosin staining,scanning electron microscopy,and transmission electron microscopy were performed to analyze the sperm morphology and *** staining and Western blot analysis were conducted to examine the effects of genetic *** identified three novel deleterious variants in DNAH6 among three unrelated *** absence of inner dynein arms and radial spokes was observed in the sperm of patients with DNAH6 ***,deficiencies in the acrosome,abnormal chromatin compaction,and vacuole-containing sperm heads were observed in these patients with DNAH6 *** decreased levels of the component proteins in these defective structures were further confirmed in sperm from patients with DNAH6 variants using Western *** intracytoplasmic sperm injection(ICSl)treatment,the partner of one patient with a DNAH6 variant achieved successful ***,novel variants in DNAH6 genes that contribute to defects in the sperm head and flagella were identified,and the findings indicated Icsl as an effective clinical treatment for such patients.

关键词： asthenoteratospermia DNAH6 intracytoplasmic sperm injection male infertility

Inverse Calculation and Regularization Process for the Solar Aspect System(SAS) of HXI Payload on ASO-S Spacecraft

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Research in Astronomy and Astrophysics 2024年第4期24卷 13-34页

作者： Ji-Rui Yu ping Ruan Yang su Ying-Hong He Jin-You Tao Zhe Zhang Song Guo Bin Xue Jian-Feng Yang Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences Xi'an 710119China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 20034China School ofAstronomy and Space Science Universityof Science and Technology of ChinaHefei 230026China

For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optimal functionality of the instrument throughout its life cycle, the Solar Aspect System (SAS) is imperative to ensure that measurements are accurate and reliable. This is achieved by capturing the target motion and utilizing a physical model-based inversion algorithm. However, the SAS optical system’s inversion model is a typical ill-posed inverse problem due to its optical parameters, which results in small target sampling errors triggering unacceptable shifts in the solution. To enhance inversion accuracy and make it more robust against observation errors, we suggest dividing the inversion operation into two stages based on the SAS spot motion model. First, the as-rigid-aspossible (ARAP) transformation algorithm calculates the relative rotations and an intermediate variable between the substrates. Second, we solve an inversion linear equation for the relative translation of the substrates, the offset of the optical axes, and the observation orientation. To address the ill-posed challenge, the Tikhonov method grounded on the discrepancy criterion and the maximum a posteriori (MAP) method founded on the Bayesian framework are utilized. The simulation results exhibit that the ARAP method achieves a solution with a rotational error of roughly±3 5 (1/2-quantile);both regularization techniques are successful in enhancing the stability of the solution, the variance of error in the MAP method is even smaller—it achieves a translational error of approximately±18μm (1/2-quantile) in comparison to the Tikhonov method’s error of around±24μm (1/2-quantile). Furthermore, the SAS practical application data indicates the method’s usability in this study. Lastly, this paper discusses the intrinsic interconnections between the regularization methods.

关键词： methods:data analysis sun:flares sun:X-rays gamma rays

Mechanical characteristics and reservoir stimulation mechanisms of the Gulong shale oil reservoirs, the northern Songliao Basin

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Petroleum Science 2024年第3期21卷 2023-2036页

作者： Si-Wei Meng Jia-ping Tao Tian-Jiao Li Dong-Xu Li su-Ling Wang Liu Yang Xin Liu Li-Hao Liang He Liu PetroChina Research Institute of Petroleum Exploration Development Beijing100083China National Key Laboratory of Continental Shale Oil Daqing 163002HeilongjiangChina Dalian University of Technology Dalian116024LiaoningChina PetroChina Daqing Oilfield Co.Ltd. Daqing163002HeilongjiangChina Northeast Petroleum University Daqing163002HeilongjiangChina China University of Mining and Technology(Beijing) Beijing100083China

Shale oil of the Qingshankou Formation of the Gulong Sag,the northern Songliao Basin,represents the first attempt at large-scale development of pure-shale-type shale oil in *** integrating the multiscale refined reservoir characterization with macro-micro-scale mechanical testing,it is clarified that the Gulong shale is characterized by high clay mineral content,high rock plasticity,highly-developed bedding,and prominent mechanical anisotropy.A three-dimensional(3D)fracture propagation model of hydraulic fracturing was built for the Gulong shale,which fully captures the hydraulic fracture distribution pattern affected by the high bedding density,in-situ stress,and fracturing treatment *** research showed that due to influences of bedding,hydraulic fracturing in the Gulong shale forms a complex fracture morphology featuring the main fracture with multiple perpendicular branches that have different lengths(like the outdoor directional TV antenna);however,the vertical propagation of fractures is inhibited,and the fracture height is commonly less than 10 *** limited stimulated reservoir volume(SRV)is the main problem facing the fracturing stimulation of the Gulong shale *** density has vital effects on fracture morphology,so case-specific fracturing designs shall be developed for shale intervals with different bedding development *** reservoirs with welldeveloped bedding,it is suggested to properly increase the perforation cluster spacing and raise the volume and proportions of viscous fluids of the pad,so as to effectively promote vertical fracture propagation and improve reservoir stimulation *** study integrates multi-scale fine reservoir characterization and macro-micro-scale mechanical testing,as well as the construction and numerical simulation of hydraulic fracturing models for high-density layered shale reservoirs,providing a new approach and methodological framework for the fracturing research of high-density layer

关键词： Shale oil Hydraulic fracturing High bedding density Fracture propagation model

Thermodynamic nature of black holes in coexistence region

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 27-32页

作者： shao-Wen Wei Yu-Xiao Liu Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Provinceand Key Laboratory of Quantum Theory and Applications of Mo ELanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China

Studying the system state of coexistence regions will peek into to reveal microscopic interactions between different phases of a thermodynamic ***,there is no effective method to study thermodynamic nature of the coexistence black hole regions for the failure of the equation of *** at these coexistence states,in this work,we develop a general approach by introducing two new ratio *** first one is the ratio of the horizon radii of the saturated coexistence small and large black holes,and the second one measures that of the small black hole molecule number to the total molecule *** demonstrate that the first parameter can serve as an order parameter to characterize the first-order phase *** study also shows that the black hole state in the coexistence region is uniquely determined by these two introduced parameters bounded between 0 and *** results are quite significant in the analytical study of phase transition and the microscopic nature of black hole in the coexistence regions.

关键词： transition. state. thermodynamic