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基于哨兵函数和S变换的风力机叶片材料损伤特性研究
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作者 廖力达 舒王咏 +3 位作者 张芝铭 刘亮 冯飞 陈为强 《太阳能学报》 EI CAS CSCD 北大核心 2024年第7期656-663,共8页
利用声发射检测技术研究玻璃纤维增强环氧树脂复合材料的损伤特性,在此过程中,采用哨兵函数来表征该材料的损伤程度,并通过S变换和模糊C均值(FCM)聚类来分析声发射信号,从而获得材料的损伤特征。三点弯曲实验结束后对试件断口进行扫描... 利用声发射检测技术研究玻璃纤维增强环氧树脂复合材料的损伤特性,在此过程中,采用哨兵函数来表征该材料的损伤程度,并通过S变换和模糊C均值(FCM)聚类来分析声发射信号,从而获得材料的损伤特征。三点弯曲实验结束后对试件断口进行扫描电子显微镜(SEM)拍照来验证,可得:通过对SEM照片的分析得到基体开裂、纤维脱粘、分层破坏、纤维断裂4种损伤模式;对整个声发射事件进行哨兵函数分析,观察到试件在弯曲过程中哨兵函数曲线呈明显下降趋势;对依据哨兵函数划分的不同阶段的信号进行VMD降噪处理,然后采用S变换进行时频分析得到不同损伤的特征频率,最后采用FCM聚类进行验证。结果表明:哨兵函数值的突变可作为材料断裂的预警信号,材料损伤类型的识别可依据S变换的频率分布结果进行确定。 展开更多
关键词 风力机叶片 复合材料 声发射 损伤特性 哨兵函数 s变换
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g-C_(3)N_(4)基S型异质结的构建及其光催化性能研究
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作者 申建宇 刘成宝 +5 位作者 郑磊之 陈丰 钱君超 邱永斌 孟宪荣 陈志刚 《功能材料》 CAS CSCD 北大核心 2024年第1期1077-1085,1097,共10页
为了解决日益严重的环境污染和能源短缺等问题,基于半导体的光催化技术利用太阳能为环境修复和能源储存提供了一种“绿色”可持续的方案。首先介绍了g-C_(3)N_(4)的优点和局限性,以及S型半导体的优势与不足,接着介绍了g-C_(3)N_(4)基S... 为了解决日益严重的环境污染和能源短缺等问题,基于半导体的光催化技术利用太阳能为环境修复和能源储存提供了一种“绿色”可持续的方案。首先介绍了g-C_(3)N_(4)的优点和局限性,以及S型半导体的优势与不足,接着介绍了g-C_(3)N_(4)基S型异质结的电子结构和光催化性质,综述了基于不同类型g-C_(3)N_(4)的S型异质结光催化材料构建和光催化性能的提升策略,并梳理了其部分应用。最后,综述了基于g-C_(3)N_(4)的S型异质结面临的挑战和未来发展趋势,有望为g-C_(3)N_(4)基S型异质结光催化材料的开发和实际应用提供重要的参考。 展开更多
关键词 g-C_(3)N_(4) s型异质结 光催化 复合材料
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Camellia密码算法S盒的量子电路优化
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作者 吕轶 罗庆斌 +1 位作者 李强 郑圆梦 《计算机科学》 CSCD 北大核心 2024年第S01期1017-1022,共6页
S盒是Camellia密码算法重要的非线性组件。使用Toffoli门、CNOT门和NOT门构建Camellia密码算法S盒的量子电路。为了降低计算的复杂度,根据S盒的代数表达式,将有限域GF(2^(8))中的乘法求逆运算同构到GF((2^(4))^(2))的复合域中的运算,构... S盒是Camellia密码算法重要的非线性组件。使用Toffoli门、CNOT门和NOT门构建Camellia密码算法S盒的量子电路。为了降低计算的复杂度,根据S盒的代数表达式,将有限域GF(2^(8))中的乘法求逆运算同构到GF((2^(4))^(2))的复合域中的运算,构造出Camellia密码算法S盒的量子电路。在优化方面,将仿射矩阵、同构矩阵以及一组CNOT门对应的矩阵先进行乘法操作,再进行综合,使用DORCIS工具优化GF(2^(4))中乘法求逆的量子电路,运用W-Type算法优化矩阵运算的量子电路。最终得到的S盒的量子电路只需使用20个量子比特,52个Toffoli门、178个CNOT门和13个NOT门,Toffoli深度为40,电路深度为130。该量子电路的正确性通过IBM公司的Aer模拟器进行验证。相比于已有的结果,文中使用的量子资源有了进一步的减少。 展开更多
关键词 量子电路 CAMELLIA s 复合域
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Rapid, accurate and serotype independent pipeline for in silico epitope mapping of SARS-CoV-2 antigens: a combined machine learning and Chou’s pseudo amino acid composition method
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作者 Arash Rahmani Mokhtar Nosrati 《Medical Data Mining》 2023年第3期1-9,共9页
Here,a new integrated machine learning and Chou’s pseudo amino acid composition method has been proposed for in silico epitope mapping of severe acute respiratorysyndrome-like coronavirus antigens.For this,a training... Here,a new integrated machine learning and Chou’s pseudo amino acid composition method has been proposed for in silico epitope mapping of severe acute respiratorysyndrome-like coronavirus antigens.For this,a training dataset including 266 linear B-cell epitopes,1,267 T-cell epitopes and 1,280 non-epitopes were prepared.The epitope sequences were then converted to numerical vectors using Chou’s pseudo amino acid composition method.The vectors were then introduced to the support vector machine,random forest,artificial neural network,and K-nearest neighbor algorithms for the classification process.The algorithm with the highest performance was selected for the epitope mapping procedure.Based on the obtained results,the random forest algorithm was the most accurate classifier with an accuracy of 0.934 followed by K-nearest neighbor,artificial neural network,and support vector machine respectively.Furthermore,the efficacies of predicted epitopes by the trained random forest algorithm were assessed through their antigenicity potential as well as affinity to human B cell receptor and MHC-I/II alleles using the VaxiJen score and molecular docking,respectively.It was also clear that the predicted epitopes especially the B-cell epitopes had high antigenicity potentials and good affinities to the protein targets.According to the results,the suggested method can be considered for developing specific epitope predictor software as well as an accelerator pipeline for designing serotype independent vaccine against the virus. 展开更多
关键词 severe acute respiratory syndrome-like coronavirus machine learning Chou’s pseudo amino acid composition epitope based vaccine
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电沉积法制备Cu(OH)_(2)/Ni-Co-S复合电极及储能特性研究
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作者 张志文 王润生 +1 位作者 刘泽仪 吕卅 《化工技术与开发》 CAS 2024年第6期1-5,共5页
本文采用两步电沉积技术,以泡沫铜为基底,原位制备了Cu(OH)_(2)/镍钴双金属硫化物(Ni-Co-S)复合电极材料。先采用恒电流沉积技术将泡沫铜表面氧化,得到Cu(OH)_(2),泡沫铜同时作为电极基底和铜的唯一来源,再通过恒电位沉积,将Ni-Co-S均... 本文采用两步电沉积技术,以泡沫铜为基底,原位制备了Cu(OH)_(2)/镍钴双金属硫化物(Ni-Co-S)复合电极材料。先采用恒电流沉积技术将泡沫铜表面氧化,得到Cu(OH)_(2),泡沫铜同时作为电极基底和铜的唯一来源,再通过恒电位沉积,将Ni-Co-S均匀覆盖在Cu(OH)_(2)表面。Cu(OH)_(2)一方面作为活性电极组分参与氧化还原反应,同时作为底层材料,为顶层Ni-Co-S的沉积提供较大的沉积空间,进而形成了更丰富的电化学活性位。基于这种原位电沉积技术以及Cu(OH)_(2)与Ni-Co-S组分的协同作用,Cu(OH)_(2)/Ni-Co-S复合电极表现出增强的赝电容特性,在2mA·cm^(-2)的放电电流密度下,比容量为4.88 F·cm^(-2),库伦效率为88.12%,5000次充放电循环后,比容量保持在初始值的86.38%。 展开更多
关键词 复合电极 电沉积 Cu(OH)_(2) Ni-Co-s
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Elastic and Plastic Behaviors of Laminated Ti-TiBw/Ti Composites 被引量:2
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作者 刘宝玺 黄陆军 GENG Lin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第3期596-600,共5页
The novel laminated Ti-TiBw/Ti composites composed of pure Ti layers and TiBw/Ti composite layers have been successfully fabricated by reactive hot pressing. Herein, two-scale structures formed: the pure Ti layer and... The novel laminated Ti-TiBw/Ti composites composed of pure Ti layers and TiBw/Ti composite layers have been successfully fabricated by reactive hot pressing. Herein, two-scale structures formed: the pure Ti layer and TiBw/Ti composite layer together constructed a laminated structure at a macro scale. Furthermore, TiBw reinforcement was distributed around Ti particles and then formed a network microstructure in TiBw/Ti composite layer at a micro scale. The laminated Ti-TiBw/Ti composites reveal a superior combination of high strength and high elongation due to two-scale structures compared with the pure Ti, and a further enhancement in ductility compared with the network structured composites. Moreover, the elastic modulus of the laminated composites can be predicted by H-S upper bound, which is consistent with the experimental values. 展开更多
关键词 titanium matrix composites laminated microstructure two-scale structure elastic modulus tensile properties H-s bounds
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SM4密码算法S盒的量子电路优化
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作者 李强 罗庆斌 +2 位作者 吕轶 郑圆梦 沈济南 《密码学报(中英文)》 CSCD 北大核心 2024年第2期455-465,共11页
S盒是SM4密码算法中的重要非线性组件.首先基于复合域理论,将S盒代数表达式中有限域GF(2^(8))中的运算同构到复合域GF((2^(4))2)中的运算,然后使用NCT门库逐步构建并优化各个运算的量子电路,最后综合出完整的S盒量子电路.为降低Toffoli... S盒是SM4密码算法中的重要非线性组件.首先基于复合域理论,将S盒代数表达式中有限域GF(2^(8))中的运算同构到复合域GF((2^(4))2)中的运算,然后使用NCT门库逐步构建并优化各个运算的量子电路,最后综合出完整的S盒量子电路.为降低Toffoli门的使用量,根据GF(24)中乘法计算的代数表达式,选取使用Toffoli门最少的量子电路.为了降低CNOT门的使用量,主要从三方面优化:一是使用最优的CNOT电路综合出4阶矩阵的量子电路;二是采用置换矩阵法以及优化子电路的方式综合出8阶矩阵的量子电路;三是通过先合并计算再综合的思路优化整个S盒中CNOT门的数量.该S盒量子电路使用Qiskit Aer量子模拟器实现,并验证了其正确性.经量子资源分析,该优化的S盒量子电路一共使用了21个量子比特、10个NOT门、152个CNOT门和34个Toffoli门,电路深度为97.Toffoli门数量、总量子逻辑门数量、电路深度等相比已有结果都有较大减少. 展开更多
关键词 量子电路 sM4 s 复合域 优化
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Fabrication and Characterization on Physico-Mechanical and Structural Properties of Sawdust Reinforced Acrylonitrile Butadiene Styrene (ABS) Composites
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作者 Budrun Neher Nabila Tasnim Nova +2 位作者 Rakib Hossain M. A. Gafur Farid Ahmed 《Materials Sciences and Applications》 2020年第9期644-658,共15页
The sawdust reinforced Acrylonitrile Butadiene Styrene (ABS) composites were prepared by using hot press molding machine for five different wt% (0%, 5%, 10%, 15% and 20%) at 180<span style="white-space:nowrap;... The sawdust reinforced Acrylonitrile Butadiene Styrene (ABS) composites were prepared by using hot press molding machine for five different wt% (0%, 5%, 10%, 15% and 20%) at 180<span style="white-space:nowrap;">&deg;</span>C temperature and 50 KN load. Sawdust was collected from local saw mill of Savar, Dhaka, Bangladesh and ABS polymer was collected from local market of Dhaka, Bangladesh. In this study, different properties of composites like physical (bulk density and water absorption), mechanical (tensile properties and hardness) and structural (Fourier Transform Infrared Spectroscopy) properties were studied. The bulk density of composites was not altered consistently and it gave greater value for 5% and 20% composites. The water absorption enhanced for all composites with the accumulation of fiber content and soaking time. The reduction of tensile strength and Leeb’s rebound hardness of the composites were observed with the increase of the fiber content in all compositions. Maximum (%) of elongation was found for 5% composite, and then it gradually decreased;however, elastic modulus increased with the increased of fiber content in composites. Fourier Transform Infrared (FTIR) spectroscopy study was done for structural characterization. It was found that there was a new bond (C≡C) stretching formed for 20% composite;moreover, C-H rocking for 0% composite was broken for all other composites after the addition of sawdust in ABS polymer matrix. 展开更多
关键词 sawdust-ABs composite Hot Press Molding Machine Tensile strength Leeb’s Rebound Hardness FTIR spectroscopy
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Adherence of <i>Streptococcus mutans</i>and Adsorption of Salivary Protein to Resin Composites Containing S-PRG Fillers
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作者 Masato Hotta Daisuke Tamura +3 位作者 Hirotomo Kotake Shusuke Kusakabe Taiyu Gen Kazuki Oike 《Open Journal of Stomatology》 2017年第3期158-168,共11页
The purpose of this study was to measure the amount of adsorption of various salivary proteins to a resin composite having various amounts of surface pre-reacted glass-ionomer (S-PRG) fillers, and to make a comparativ... The purpose of this study was to measure the amount of adsorption of various salivary proteins to a resin composite having various amounts of surface pre-reacted glass-ionomer (S-PRG) fillers, and to make a comparative study of the adherence of S. mutans to the resin composite covered by various salivary proteins. We experimentally produced resin composites (S-PRG resin) having the basic composition of Bis-GMA/TEGDMA and various amount of the S-PRG fillers ranging between 0 - 60 wt%. Each S-PRG resin block was soaked in 5 kinds of components found in salivary fluid (Mucin 1, Lactoferrin, IgA, Cystatin C, and Lysozyme), and the amount of adsorption was measured by use of a spectrophotometer. The amount of the adsorption of salivary Mucin 1 was higher than that of any other salivary component tested regardless of the percentage of the S-PRG filler. In the case of salivary Lysoxyme used for coating, the amount of its adsorption increased with an increase in the percentage of the S-PRG filler. In addition, resin blocks coated with various salivary proteins were incubated at 37℃ for 2 hours with radio-labeled S. mutans for a quantitative adherence test. Labeled bacteria that adhered to the resin blocks were collected by using an automatic sample combustion system and a liquid scintillation counter. The absorbed salivary components, especially Mucin 1 and Lysozyme, inhibited the adhesion of S. mutans to the S-PRG resin;however, these changes were generally directional rather than statistically significant. 展开更多
关键词 s-PRG Filler sALIVARY PROTEIN Oral Bacteria Resin composite
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山区S形曲线桥梁施工关键技术研究
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作者 黄国雄 《价值工程》 2024年第21期82-84,共3页
针对山区公路桥梁施工存在的机械材料运输困难、施工组织难度大等问题,本文旨在提出一套适用于山区S形曲线桥梁施工的预制T形组合梁制作、运输和安装方法,以提高施工效率和质量。首先分析山区桥梁施工的特点,对S形曲线桥梁中T形组合梁... 针对山区公路桥梁施工存在的机械材料运输困难、施工组织难度大等问题,本文旨在提出一套适用于山区S形曲线桥梁施工的预制T形组合梁制作、运输和安装方法,以提高施工效率和质量。首先分析山区桥梁施工的特点,对S形曲线桥梁中T形组合梁的预制流程及施工控制要点开展技术创新和优化。首先提出了改进的T梁预制方法,基于钢筋定位架优化了钢筋布设精度和效率,并通过智能张拉设备、自动喷淋系统等智能化手段,有效提高了预制梁的成品品质。其次,针对安装效率的挑战,研究提出了一种左右幅整体架设的预制梁安装方案,基于此对T形组合梁的安装流程进行了优化。通过在某大桥项目中的实际应用与验证,结果表明,本技术方案可提高T梁预制和架设精度,有效控制S形桥梁纵向及横向的线形。本研究为山区S形曲线桥梁施工提供了一套T形组合梁从生产到安装的全过程标准化技术方案,为类似项目提供了宝贵的技术参考与实践指导。 展开更多
关键词 s形曲线桥梁 T形组合梁 装配式桥梁 混凝土养护 预应力张拉
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黑龙江争光大型金矿成矿流体He-Ar-S同位素组成及成矿流体来源的示踪
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作者 刘宝山 张春鹏 +3 位作者 程招勋 寇林林 李成禄 韩仁萍 《中国地质》 CAS CSCD 北大核心 2023年第3期952-961,共10页
【研究目的】黑龙江争光金矿床位于兴安地块东缘嫩江—黑河北东向断裂带西北侧的奥陶纪多宝山岛弧带上。本文通过对主成矿期的矿石样品研究,探讨了成矿流体的来源。【研究方法】选择9件主成矿期的黄铁矿和方铅矿进行了系统研究,测定了He... 【研究目的】黑龙江争光金矿床位于兴安地块东缘嫩江—黑河北东向断裂带西北侧的奥陶纪多宝山岛弧带上。本文通过对主成矿期的矿石样品研究,探讨了成矿流体的来源。【研究方法】选择9件主成矿期的黄铁矿和方铅矿进行了系统研究,测定了He、Ar和S同位素组成。【研究结果】其含金石英脉中黄铁矿和方铅矿的流体包裹体3He/4He=1.95×10^(-6)~5.03×10^(-6),^(40)Ar/^(36)Ar=349.1~453.9。幔源He占13.17%~44.67%,平均27.58%,显示了成矿流体以大气降水为主,但同时有地幔流体成分,表明金矿床成矿作用与地幔活动有着密切的关系。矿物δ^(34)S=-1.2‰~-3.9‰,平均-2.33‰,可能来自深源地幔流体,但其中有地壳流体的加入。【结论】洋壳向兴安地块俯冲,俯冲流体交代地幔楔发生部分熔融,流体上升至地表浅部与下渗的大气降水混合形成成矿流体,由于温度和压力的下降和流体沸腾作用导致成矿流体物理化学条件的改变,从而使成矿物质沉淀。 展开更多
关键词 He-Ar-s同位素 壳幔相互作用 争光大型金矿 地质调查工程 大兴安岭
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Composite diffuse large B-cell lymphoma and classical Hodgkin's lymphoma of the stomach:Case report and literature review 被引量:5
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作者 Hong-Wei Wang Wen Yang +2 位作者 Lin Wang Yun-Long Lu Jiang-Yang Lu 《World Journal of Gastroenterology》 SCIE CAS 2013年第37期6304-6309,共6页
The combination of classical Hodgkin’s lymphoma(cHL)and non-Hodgkin lymphoma coexisting in the same patient is not common,especially in one extranodal location.Here we present a rare case of composite diffuse large B... The combination of classical Hodgkin’s lymphoma(cHL)and non-Hodgkin lymphoma coexisting in the same patient is not common,especially in one extranodal location.Here we present a rare case of composite diffuse large B-cell lymphoma(DLBCL)and cHL occurring simultaneously in the stomach of a 53-year-old female who presented with upper abdominal discomfort and gas pain.Surgery was performed and the disease was diagnosed pathologically as composite lymphoma of DLBCL and cHL using hematoxylin-eosin and immunohistochemical staining.Epstein-Barr virus(EBV)infection was not detected by in situ hybridization for EBV-encoded RNA or immunohistochemistry for EBV latent membrane protein-1.Polymerase chain reaction analysis from the two distinct components of the tumor demonstrated clonal immunoglobulinκlight chain gene rearrangements.The patient died approximately 11 mo after diagnosis in spite of receiving eight courses of the CHOP and two courses of the rituximab-CHOP(RCHOP) chemotherapy regimen.This case report showed that the two distinct components,DLBCL and cHL,appeared to originate from the same clonal progenitor cell,and that EBV infection was not essential for transformation during the course of tumorigenesis. 展开更多
关键词 compositE LYMPHOMA DIFFUsE large B-CELL LYMPHOMA Hodgkin’s LYMPHOMA sTOMACH
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Soil fungistasis and its relations to soil microbial composition and diversity:A case study of a series of soils with different fungistasis 被引量:7
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作者 Wu Minna Zhang Huiwen +3 位作者 Ll Xinyu Zhang Yan Su Zhencheng Zhang Chenggang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期871-877,共7页
Fungistasis is one of the important approaches to control soil-borne plant pathogens.Some hypotheses about the mechanisms for soil fungistasis had been established,which mainly focused on the soil bacterial community ... Fungistasis is one of the important approaches to control soil-borne plant pathogens.Some hypotheses about the mechanisms for soil fungistasis had been established,which mainly focused on the soil bacterial community composition,structure,diversity as well as function.In this study,the bacterial community composition and diversity of a series of soils treated by autoclaving,which coming from the same original soil sample and showing gradient fungistasis to the target soil-borne pathogen fungi Fusarium grami... 展开更多
关键词 soil fungistasis 16s rDNA clone library microbial diversity bacterial community composition
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Weighted composition operators from F(p,q,s) spaces to Bers-type spaces in the unit ball 被引量:2
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作者 LU Xiao-fen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期462-472,共11页
This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to ... This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal. 展开更多
关键词 F(p Q s space Bers-type space weighted composition operator unit ball
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Tempura-like carbon/carbon composite as advanced anode materials for K-ion batteries 被引量:6
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作者 Hao-Jie Liang Zhen-Yi Gu +7 位作者 Xue-Ying Zheng Wen-Hao Li Ling-Yun Zhu Zhong-Hui Sun Yun-Feng Meng Hai-Yue Yu Xian-Kun Hou Xing-Long Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第8期589-598,I0012,共11页
Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To pr... Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To protect the layer structure and further boost performance,tempura-like carbon/carbon nanocomposite of graphite@pitch-derived S-doped carbon(G@PSC)is designed and prepared by a facile and low-temperature modified molten salt method.This robust encapsulation structure makes their respective advantages complementary to each other,showing mutual promotion of electrochemical performances caused by synergy effect.As a result,the G@PSC electrode is applied in KIBs,delivering impressive rate capabilities(465,408,370,332,290,and 227 m A h g^(-1)at 0.05,0.2,0.5,1,2,and 5 A g^(-1))and ultralong cyclic stability(163 m A g^(-1)remaining even after 8000 cycles at 2 A g^(-1)).On basis of ex-situ studies,the sectionalized K-storage mechanism with adsorption(pseudocapacitance caused by S doping)-intercalation(pitch-derived carbon and graphite)pattern is revealed.Moreover,the exact insights into remarkable rate performances are taken by electrochemical kinetics tests and density functional theory calculation.In a word,this study adopts a facile method to synthesize high-performance carbon/carbon nanocomposite and is of practical significance for development of carbonaceous anode in KIBs. 展开更多
关键词 K-ion batteries Anode materials Carbon/carbon composite s doping Cyclic stability DFT calculation
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一种基于复合域的国密SM4算法快速软件实现方法 被引量:4
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作者 陈晨 郭华 +2 位作者 王闯 刘源灏 刘建伟 《密码学报》 CSCD 2023年第2期289-305,共17页
成为ISO/IEC国际标准算法后,SM4的性能受到更多关注.目前针对SM4算法实现效率提升的方法主要集中在缩短S盒的运算时间,其中采用复合域实现的方法大都基于AES算法实现的复合域,而在GF((2^(4))^(2))上鲜有针对SM4算法软件实现的复合域被提... 成为ISO/IEC国际标准算法后,SM4的性能受到更多关注.目前针对SM4算法实现效率提升的方法主要集中在缩短S盒的运算时间,其中采用复合域实现的方法大都基于AES算法实现的复合域,而在GF((2^(4))^(2))上鲜有针对SM4算法软件实现的复合域被提出.本文首次在GF((2^(4))^(2))上找到了一个针对SM4算法S盒软件实现的复合域,给出一种基于复合域的SM4算法快速软件实现方法,使用穷举搜索和数学分析优化了算法S盒的复合域数学构造,构建了同构映射矩阵及其最小化目标函数,仅使用175个门函数就完成了S盒运算,平均每个输出比特占用22个门函数.基于比特切片技术,利用扩展指令集AVX2实现了SM4算法256组消息的并行化加密.每字节加解密平均耗时仅6.5个时钟周期.对硬件依赖程度低,经测试在Intel i5、Intel i7和AMD R7环境下均能显著提升SM4算法的计算效率,对有相似S盒结构的密码算法快速软件实现具有重要的参考价值. 展开更多
关键词 sM4算法 s 复合域 比特切片 AVX2扩展指令集
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3D skeleton nanostructured Ni_3S_2/Ni foam@RGO composite anode for high-performance dual-ion battery 被引量:4
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作者 Shuai Wang Jiguo Tu +2 位作者 Jiusan Xiao Jun Zhu Shuqiang Jiao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第1期144-150,共7页
The growing global demands of safe, low-cost and high working voltage energy storage devices trigger strong interests in novel battery concepts beyond state-of-art lithium-ion battery. Herein, a dualion battery based ... The growing global demands of safe, low-cost and high working voltage energy storage devices trigger strong interests in novel battery concepts beyond state-of-art lithium-ion battery. Herein, a dualion battery based on nanostructured Ni_3S_2/Ni foam@RGO(NSNR) composite anode is developed, utilizing graphite as cathode material and LiPF6-VC-based solvent as electrolyte. The battery operates at high working voltage of 4.2–4.5 V, with superior discharge capacity of ~90 m A h g^(-1) at 100 mA g^(-1), outstanding rate performance, and long-term cycling stability over 500 cycles with discharge capacity retention of ~85.6%. Moreover, the composite simultaneously acts as the anode material and the current collector, and the corrosion phenomenon can be greatly reduced compared to metallic Al anode. Thus, this work represents a significant step forward for practical safe, low-cost and high working voltage dual-ion batteries,showing attractive potential for future energy storage application. 展开更多
关键词 Dual-ion BATTERY NANOsTRUCTURED Ni3s2/Ni foam@RGO composite High working voltage Long-term cycling
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Analysis of cultivable aerobic bacterial community composition and screening for facultative sulfate-reducing bacteria in marine corrosive steel 被引量:4
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作者 LI Xiaohong XIAO Hui +7 位作者 ZHANG Wenjun LI Yongqian TANG Xuexi DUAN Jizhou YANG Zhibo WANG Jing GUAN Fang DING Guoqing 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2019年第2期600-614,共15页
Anaerobic, aerobic, and facultative bacteria are all present in corrosive environments. However, as previous studies to address corrosion in the marine environment have largely focused on anaerobic bacteria, limited a... Anaerobic, aerobic, and facultative bacteria are all present in corrosive environments. However, as previous studies to address corrosion in the marine environment have largely focused on anaerobic bacteria, limited attention has been paid to the composition and function of aerobic and facultative bacteria in this process. For analysis in this study, ten samples were collected from rust layers on steel plates that had been immersed in seawater for diff erent periods (i.e., six months and eight years) at Sanya and Xiamen, China. The cultivable aerobic bacterial community structure as well as the number of sulfate-reducing bacteria (SRB) were analyzed in both cases, while the proportion of facultative SRB among the isolated aerobic bacteria in each sample was also evaluated using a novel approach. Bacterial abundance results show that the proportions are related to sea location and immersion time;abundances of culturable aerobic bacteria (CAB) and SRB from Sanya were greater in most corrosion samples than those from Xiamen, and abundances of both bacterial groups were greater in samples immersed for six months than for eight years. A total of 213 isolates were obtained from all samples in terms of CAB community composition, and a phylogenetic analysis revealed that the taxa comprised four phyla and 31 genera. Bacterial species composition is related to marine location;the results show that Firmicutes and Proteobacteria were the dominant phyla, accounting for 98.13% of the total, while Bacillus and Vibrio were the dominant genera, accounting for 53.06% of the total. An additional sixfacultative SRB strains were also screened from the isolates obtained and were found to encompass the genus Vibrio (four strains), Staphylococcus (one strain), and Photobacterium (one strain). It is noteworthy that mentions of Photobacterium species have so far been absent from the literature, both in terms of its membership of the SRB group and its relationship to corrosion. 展开更多
关键词 MARINE corrosive sTEEL cultivable AEROBIC BACTERIA FACULTATIVE sulfate-reducing BACTERIA bacterial community composition 16s RRNA gene sequencing
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Synthesis and evaluation of a novel antibacterial dental resin composite with quaternary ammonium salts 被引量:1
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作者 Yiming Weng Xia Guo +3 位作者 Voon Joe Chong Leah Howard Richard L. Gregory Dong Xie 《Journal of Biomedical Science and Engineering》 2011年第3期147-157,共11页
The novel quaternary ammonium bromide (QAB)-containing oligomers were synthesized and applied for developing an antibacterial resin composite. Compressive strength (CS) and S. mutans (an oral bacteria strain) viabilit... The novel quaternary ammonium bromide (QAB)-containing oligomers were synthesized and applied for developing an antibacterial resin composite. Compressive strength (CS) and S. mutans (an oral bacteria strain) viability were used to evaluate the mechanical strength and antibacterial activity of the formed composites. All the QAB-modified resin composites showed significant antibacterial activity and mechanical strength reduction. Increasing chain length and loading significantly enhanced the antibacterial activity but dramatically reduced the CS as well. The 30-day aging study showed that the incorporation of the QAB accelerated the degradation of the composite, suggesting that the QAB may not be well suitable for development of antibacterial dental resin composites or at least the QAB loading should be well controlled, unlike its use in dental glass-ionomer cements. The work in this study is beneficial and valuable to those who are interested in studying antibacterial dental resin composites. 展开更多
关键词 QAB sUBsTITUTE chain length ANTIBACTERIAL s. MUTANs VIABILITY Cs DENTAL REsIN composites
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Numerical Modelling of the Transient Hygroscopic Behavior of Flax-Epoxy Composite 被引量:1
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作者 Wajdi Zouari Mustapha Assarar +2 位作者 Abderrazak Chilali Rezak Ayad Hocine Kebir 《Journal of Renewable Materials》 SCIE 2019年第9期839-853,共15页
This contribution deals with the development of a three-node triangular plane finite element to analyze the transient hygroscopic behavior of 2/2 twill flax fabric-reinforced epoxy composite.Several plates of this mat... This contribution deals with the development of a three-node triangular plane finite element to analyze the transient hygroscopic behavior of 2/2 twill flax fabric-reinforced epoxy composite.Several plates of this material were fabricated using the vacuum infusion process and composite specimens were then cut and aged in tap water at room temperature until saturation.To simplify,a plane modelling of water diffusion in the aged specimens is adopted and Fick’s model is used to describe the water diffusion kinetics.To highlight the heterogeneity of the flax-epoxy samples,the twill flax fabrics waviness is modelled with a sinusoidal undulation.In particular,we show that the proposed finite element formulation allows estimating the flax fiber radial diffusion coefficient by an inverse approach. 展开更多
关键词 Flax-epoxy composite water ageing fick’s model finite element analysis
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