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多源知识融合的方面级情感分析模型

北京航空航天大学学报 2024年第9期50卷 2688-2695页

作者：韩虎郝俊张千锟赵启涛兰州交通大学电子与信息工程学院兰州730070

方面级情感分析(ABSA)是一项细粒度情感分析任务,其目的是针对评论语句中出现的特定方面给出对应的情感极性。现有的基于深度学习的ABSA方法大多侧重于评论语句语义和句法的挖掘,往往忽略了评论语句可能涉及的概念知识和情感程度信息。... 详细信息

方面级情感分析(ABSA)是一项细粒度情感分析任务,其目的是针对评论语句中出现的特定方面给出对应的情感极性。现有的基于深度学习的ABSA方法大多侧重于评论语句语义和句法的挖掘,往往忽略了评论语句可能涉及的概念知识和情感程度信息。针对此问题,提出一种融合多源知识的神经网络模型,通过句法依赖揭示句子的结构框架、词共现捕捉单词之间的语义联系、情感网络和概念图谱的嵌入为模型提供情感和背景知识,共同实现评论语句上下文与评价方面的增强表示,并通过双交互注意力模式实现评论语句上下文与评价方面的协调优化。通过在4个公开数据集上的实验验证,该模型在ABSA任务中,准确率分别达到了75.00%、77.90%、81.55%、90.10%,与基准模型相比均有所提高。研究成果不仅验证了多源知识融合在ABSA任务中的有效性,也为未来的研究提供了新的思路和方法。

关键词：方面级情感分析图卷积网络多源融合知识图谱交互注意力机制

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石墨管与不锈钢管钎焊接头的组织和残余应力

材料科学与工艺 2024年第4期32卷 19-27页

作者：肖逸锋陈锦微张汭宋章王晖张乾坤吴靓湘潭大学机械工程与力学学院湖南湘潭411105 焊接机器人及应用技术湖南省重点实验室(湘潭大学) 湖南湘潭411105 复杂轨迹加工工艺及装备教育部工程研究中心(湘潭大学) 湖南湘潭411105

为使石墨材料能够在空间核电散热装置中更充分地发挥其价值,本文采用BNi-2钎料真空钎焊连接等静压石墨管和304不锈钢管,研究了石墨/BNi-2/不锈钢接头在1010℃、保温90 min条件下的显微组织和不同冷却工艺对接头残余应力的影响。研究表明... 详细信息

为使石墨材料能够在空间核电散热装置中更充分地发挥其价值,本文采用BNi-2钎料真空钎焊连接等静压石墨管和304不锈钢管,研究了石墨/BNi-2/不锈钢接头在1010℃、保温90 min条件下的显微组织和不同冷却工艺对接头残余应力的影响。研究表明:在1010℃,保温90 min条件下,钎焊接头致密无裂纹,Cr元素在石墨侧与石墨基体反应形成Cr_(7)C_(3)反应层,在不锈钢侧形成了σ-FeCr扩散层,界面接头组成为石墨/Cr_(7)C_(3)/Ni(s,s)+Ni_(3)Si/σ-FeCr/不锈钢;经缓冷工艺处理的接头,常温剪切强度为28.38 MPa,比炉冷处理的接头剪切强度提高了22%;有限元数值分析结果表明,采用缓慢冷却的钎焊工艺可以有效缓解钎焊接头在冷却过程中产生的残余应力,符合剪切实验结果。

关键词：镍基钎料石墨管不锈钢管力学性能有限元数值分析钎焊

退火处理对CrNiTiMoV高熵合金组织与性能的影响

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热加工工艺 2024年第4期53卷 141-145页

作者：夏秀艳肖逸锋吴靓张乾坤湘潭大学机械工程学院湖南湘潭411105

采用真空电弧熔炼的方法制备CrNiTiMoV高熵合金,分别在600、700、800和900℃下对合金进行2h退火处理。利用X射线衍射仪(XRD)、扫描电镜(SEM)、能谱仪(EDS)、显微硬度计以及电化学工作站对铸态和退火态合金的组织、硬度和耐腐蚀性能进行... 详细信息

采用真空电弧熔炼的方法制备CrNiTiMoV高熵合金,分别在600、700、800和900℃下对合金进行2h退火处理。利用X射线衍射仪(XRD)、扫描电镜(SEM)、能谱仪(EDS)、显微硬度计以及电化学工作站对铸态和退火态合金的组织、硬度和耐腐蚀性能进行了研究。结果表明:CrNiTiMoV高熵合金具有典型的树枝晶形貌,晶体结构由简单的BCC相和少量的NiTi相以及富Ti相构成;CrNiTiMoV高熵合金经不同温度退火后未出现新相,随着退火温度升高,富Ti相析出强化,使得合金硬度上升,均大于铸态合金硬度517HV,在800℃/2h退火后,合金硬度达到最大为684HV;在600℃/2h退火后,合金耐腐蚀性能明显提高,但随着退火温度的提高,合金晶粒粗化,富Ti相的析出导致Ti分布不均匀,降低了整体的耐腐蚀性能。

关键词：热处理高熵合金组织耐腐蚀性能

聚酰亚胺复合膜的制备及其在沼气提纯中的应用

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天津工业大学学报 2024年第4期43卷 7-11,18页

作者：丁晓莉王巍骥张乾坤张智铭赵红永天津工业大学材料科学与工程学院天津300387 天津工业大学化学工程与技术学院天津300387

为解决沼气分离过程中单级膜过程产物CO_(2)纯度低及CH4的损失率较高等问题,通过界面聚合法制备了具有超高分离性能的具有聚酰亚胺分离层的复合膜,研究了操作温度、进料侧压力及切割比等因素对分离效果的影响。结果表明:该膜适用的温度... 详细信息

为解决沼气分离过程中单级膜过程产物CO_(2)纯度低及CH4的损失率较高等问题,通过界面聚合法制备了具有超高分离性能的具有聚酰亚胺分离层的复合膜,研究了操作温度、进料侧压力及切割比等因素对分离效果的影响。结果表明:该膜适用的温度及压力范围较广,不同操作条件下的膜均表现出了优异的分离性能,产出的CO_(2)纯度高,CH4的损失率低。低温、低压、低切割比有利于渗透侧高纯CO_(2)的输出;高温、高压、低切割比则有利于渗余侧CH4的回收。使用该膜模拟沼气分离,在切割比为0.1下操作,当进气压力为0.2 MPa、温度为25℃时,通过单级膜过程,渗透侧可得到99%的CO_(2),渗余侧CH4回收率可高达99%。在很宽的操作范围内,本文制备的复合膜在沼气中CO_(2)组分分离时,CH4损失率可控制在1%范围内,是理想的CO_(2)/CH4分离膜。

关键词：复合膜二氧化碳捕集聚酰亚胺界面聚合沼气提纯

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基于症状管理策略的健康教育在高通量血液透析患者中的应用效果

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中国医药导报 2024年第15期21卷 152-155页

作者：蔡意张乾坤丁靖翔温州医科大学附属第五医院浙江省丽水市中心医院血液净化中心浙江丽水323000 温州医科大学附属第五医院浙江省丽水市中心医院肾内科浙江丽水323000

目的研究基于症状管理策略的健康教育在高通量血液透析患者中的效果。方法选取浙江省丽水市中心医院2022年1月至2023年3月收治的高通量血液透析患者90例,根据随机数字表法将其分为常规组(45例,行常规健康教育干预)和症状管理组(45例,... 详细信息

目的研究基于症状管理策略的健康教育在高通量血液透析患者中的效果。方法选取浙江省丽水市中心医院2022年1月至2023年3月收治的高通量血液透析患者90例,根据随机数字表法将其分为常规组(45例,行常规健康教育干预)和症状管理组(45例,行基于症状管理策略的健康教育干预),两组均干预3个月。比较两组干预前后的体适能指标、自我管理能力,分析两组临床依从性。结果干预后,症状管理组有氧耐力、上肢肌力、下肢肌力、动态平衡能力均优于本组干预前及对照组(P<0.05)。干预后,两组自我管理能力、自我管理意识、健康认知、自我概念评分均高于治疗前,且症状管理组高于常规组(P<0.05)。症状管理组临床依从性优于常规组(P<0.05)。结论基于症状管理策略的健康教育在高通量血液透析患者中应用效果较好。

关键词：血液透析高通量症状管理策略健康教育体适能营养状态临床依从性

Preparation and Thermal Shock Resistance of Mullite and Corundum Co-bonded SiC Ceramics for Solar Thermal Storage

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 16-25页

作者：徐晓虹宋佳 WU Jianfeng zhang Yaxiang ZHOU Yang zhang qiankun State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

Mullite and corundum co-bonded SiC-based composite ceramics(SiC-mullite-Al2O3)were prepared by using SiC,calcined bauxite and kaolin via pressureless carbon-buried *** low-cost SiC-based composite ceramics designed in this study are expected to be used as thermal storage materials in solar thermal power generation based on the high density and excellent thermal shock *** influences of calcined bauxite addition and sintering temperature on the microstructures,phase compositions,and physical properties of the samples were *** demonstrated that the introduction of calcined bauxite containing two bonding phases greatly reduced the lowest sintering temperature to 1400℃.The SiC-mullite Al2O3 composite with 40 wt%calcined bauxite sintered at 1500℃exhibited optimum *** density and bending strength were 2.27 g·cm^-3 and 77.05 *** bending strength increased by 24.58%and no cracks were observed after 30 thermal shock cycles,while general clay would reduce the thermal shock resistance of *** SiC-mullite-Al2O3 composites with satisfied performance are expected to be used as thermal storage materials in solar thermal power generation systems.

关键词： SiC-mullite-Al2O3 composite ceramics calcined bauxite solar thermal storage mechanical performance thermal shock resistance

PM2RA: A Framework for Detecting and Quantifying Relationship Alterations in Microbial Community

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Genomics, Proteomics & Bioinformatics 2021年第1期19卷 154-167页

作者： Zhi Liu Kai Mi Zhenjiang Zech Xu qiankun zhang Xingyin Liu State Key Laboratory of Reproductive Medicine Center of Global HealthNanjing Medical UniversityNanjing 211166China Department of Pathogen Biology-Microbiology Division Key Laboratory of Pathogen Biology of Jiangsu ProvinceNanjing Medical UniversityNanjing 211166China Key Laboratory of Human Functional Genomics of Jiangsu Province Nanjing Medical UniversityNanjing 211166China School of Food and Technology State Key Laboratory of Food Science and TechnologyNanchang UniversityNanchang 330031China Key Laboratory of Holistic Integrative Enterology Second Affiliated Hospital of Nanjing Medical UniversityNanjing 210003China

The dysbiosis of gut microbiota is associated with the pathogenesis of human ***,observing shifts in the microbe abundance cannot fully reveal underlying *** the relationship alterations(RAs)in the microbiome between health and disease statuses provides additional hints about the pathogenesis of human diseases,but no methods were designed to detect and quantify the RAs between different conditions ***,we present profile monitoring for microbial relationship alteration(PM2 RA),an analysis framework to identify and quantify the microbial *** performance of PM2 RA was evaluated with synthetic data,and it showed higher specificity and sensitivity than the co-occurrence-based *** of real microbial datasets showed that PM2 RA was robust for quantifying microbial RAs across different datasets in several *** applying PM2 RA,we identified several novel or previously reported microbes implicated in multiple ***2 RA is now implemented as a web-based application available at http://***2 ***/.

关键词： Microbiome Microbial relationship alteration Profile monitoring Network Human disease Microbial community

Cordierite Ceramics Prepared from Poor Quality Kaolin for Electric Heater Supports: Sintering Process, Phase Transformation, Microstructure Evolution and Properties

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Journal of Wuhan University of Technology(Materials Science) 2018年第3期33卷 598-607页

作者：吴建锋陆成龙 XU Xiaohong zhang Yaxiang WANG Dongbin zhang qiankun State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology

To efficiently utilize the kaolin, an economical way of preparing cordierite ceramic with high performance for electric heater supports was put forward. In this study, sintering process, phase transformation, microstructure evolutions were systematically studied by heating microscope, X-ray diffraction, scanning electronic microscope and thermal analysis. Properties（physical properties, electrical properties and coefficient of thermal expansion（CTE）） were tested for comprehensive performance evaluation. The results showed that the utilization of poor quality kaolin broadened the firing range of cordierite ceramic which was from 1 200 to 1 380 ℃. Microstructure becomes loose with increasing of the pore size, which had significant influence on bending strength and electrical properties. High content of K2 O in poor quality kaolin was the reason for liquid phase generation in sintering process, which further leads to microstructural changes. The cordierite ceramic sintered at 1 320 ℃ had the properties as follows： CTE of 1.98×10^（-6） ℃^（-1）（500 ℃）, bending strength of 90 MPa, apparent porosity of 15.1%, dielectric constant of 7.5（100 Hz）, and volume resistivity of 1.05×109 Ω·cm（100 Hz）. The comprehensive properties are very suitable for use as electric heater supports.

关键词： cordierite ceramic poor quality kaolin microstructure-final electrical properties electric heater supports

Living/controlled polymerization of vinylpyridines into sequence-regulated copolymers by Lewis pair

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Science China Chemistry 2024年第8期67卷 2737-2746页

作者： qiankun Ding Wuchao Zhao Fukuan Li Jianghua He Yuetao zhang Department of State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

The poly(vinylpyridine)(PVP) based(co)polymers are of particular interest in materials science, due to their multifunctionality and diverse applications. So far, there is no report on the sequence-regulated copolymerization of vinylpyridines(VPs) and methacrylate monomer in one-step manner yet. Here we designed and synthesized a series of guanidine phosphines as Lewis base(LB), which is combined with bulky organoaluminium to construct Lewis pairs(LPs) for polymerization of VPs. The living/controlled polymerization of 4-vinylpyridine(4-VP) or 2-vinylpyridine(2-VP) can be accomplished with remarkable efficiency by such Lewis pair polymerization(LPP), furnishing polymers with high molecular weight(up to 288 kg/mol) and narrow molecular weight distribution(as low as 1.17). Mechanistic studies reveal the interaction of LPs and formation of zwitterionic intermediates, providing solid evidences to support the proposed polymerization mechanism. More importantly, by simply adjusting the LA dosage, this LPP strategy realizes the unprecedented control over the sequence regulation of 2-VP-based copolymers from gradient to block in one-step manner, regardless of the monomer ratio, which greatly expands the versatility of the LPP.

关键词： guanidine phosphine Lewis pair polymerization living/controlled polymerization vinyl pyridine sequence regulation