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Magnetic Resonance Letters 2022年第2期2卷 91-106,I0003页

作者： Chunfa Li ting Huang Yubin Bao Zhe chen Guangxin Lin SABIC R&D Center(China)Co. LtdShanghai201319China SABIC Mount VernonUSIN47620USA

Side reaction pathways are observed to occur between antioxidants and peroxide during the processing of multiple resin grades mediated by controlled peroxide-induced degradation of impact *** the present work,the reaction mechanism and main by-products between antioxidants and peroxides were *** results demonstrate that peroxides greatly accelerate the decomposition reactions,and the free radicals formed from peroxide decomposition react with,for example,the antioxidant AO1010 to produce dehydrogenation of phenyl propionic unit(s)at the a position(cinnamic acid ester moiety),which generates a conjugated system leading to the increased color of the *** is the first time to confirm the cinnamic acid moiety's existence and report its NMR ***,this work confirms the dehydrogenation mechanism by comparison with different sterically hindered phenolic *** also systematically summarizes the oxidation and degradation mechanism of AO168 and AO1010 under air and peroxide environments,*** on present study,clear guidelines are obtained to improve the quality of polymeric products,especially the appearance and stability,during product development.

关键词： Peroxide Antioxidant Free radical Cinnamic acid ester Polypropylene

基于扩散模型的自监督预训练血管内超声图像分割方法

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激光与光电子学进展 2024年第18期61卷 365-373页

作者：郝文月蔡怀宇左廷涛贾忠伟汪毅陈晓冬天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室乐普(北京)医疗器械股份有限公司鲁西南医院

为了克服获取大规模有标签数据集的困难，引入一种基于扩散模型的代理任务，通过自监督学习从未标注的数据集中获取先验知识，并在小规模有标签的数据集上进行微调。受扩散模型的启发，使用不同等级的噪声与原图加权混合作为模型输入，... 详细信息

为了克服获取大规模有标签数据集的困难，引入一种基于扩散模型的代理任务，通过自监督学习从未标注的数据集中获取先验知识，并在小规模有标签的数据集上进行微调。受扩散模型的启发，使用不同等级的噪声与原图加权混合作为模型输入，并训练模型预测输入的噪声，以更好地学习血管内超声（IVUS）图像的表征。此外，引入均方误差（MSE）和结构相似性指数（SSIM）的联合损失函数以提高模型性能。所提方法在20%数据集上的实验结果表明：所得内膜和中膜的Jaccard度量（JM）系数相比于随机初始化的结果分别提高了0.044和0.101,Hausdorff距离（HD）系数分别改进了0.216和0.107，达到了与使用100%数据集训练相近的结果。该框架可以适用于任何结构图像分割模型，并在确保分割效果的同时，显著降低了对真值标签的依赖。

关键词：医学图像分割血管内超声表征学习扩散模型

PSO-LSTM-TMPH模型在水库调蓄流域径流模拟中的应用

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中国农村水利水电 2024年第5期 191-199,214页

作者：陈润庭林泳恩林泽群张智庄胜杰王大刚中山大学地理科学与规划学院广东广州510000

水库的建设和运行使得水库下游流量发生了显著改变,为了在月径流模拟中充分考虑水库的调蓄作用,选择东江流域作为典型流域,使用粒子群算法优化的长短期神经网络(Particle Swarm Optimization-Long Short Term Memory,PSO-LSTM)对东江流... 详细信息

水库的建设和运行使得水库下游流量发生了显著改变,为了在月径流模拟中充分考虑水库的调蓄作用,选择东江流域作为典型流域,使用粒子群算法优化的长短期神经网络(Particle Swarm Optimization-Long Short Term Memory,PSO-LSTM)对东江流域的3个多功能水库枫树坝、新丰江、白盆珠水库的出流进行了模拟,并与传统的水库模型Level Pool Scheme(LPS)进行对比;使用三参数月度水文模型(Three-Parameter Monthly Hydrological Model Based on the Proportionality Hypothesis,TMPH)进行水库入流和区间来水模拟,与上述两种水库出流模型结合分别形成PSO-LSTM-TMPH和LPS-TMPH对东江流域重要站点龙川、河源、岭下、博罗进行预见期为一个月的径流模拟。结果表明:①PSO-LSTM在三大水库的模拟中效果均好于LPS,尤其在新丰江水库出流模拟中,在验证期的纳什效率系数(Nash-Sutcliffe Efficiency,NSE)、均方根误差(Root Mean Square Error,RMSE)分别为0.59、55.59 m^(3)/s,相比LPS提高了0.22,降低了17.01 m^(3)/s,说明该模型可以很好地捕捉多年调节水库复杂的水库出流规则;②PSO-LSTM-TMPH模拟龙川站、河源站、岭下站、博罗站径流的NSE为0.87,0.86,0.91,0.93,相比LPS-TMPH,NSE提高了0.09、0.21、0.07、0.03;③在测试期内,PSO-LSTM-TMPH水库出流模拟效果仍然较好,相比训练期、验证期模拟效果差异小,说明模型的模型泛化能力较强。研究建立的PSOLSTM-TMPH混合模型可以结合深度学习和物理模型各自的优势,适用于人类活动干扰下的径流模拟,可为优化水资源利用、实施干旱调度等提供技术支撑。

关键词： TMPH模型 LSTM PSO 水库调蓄径流模拟东江流域

深冷处理对Al_(1.2)CrFe_(2)Ni_(2)高熵合金组织和性能的影响

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铸造 2024年第4期73卷 469-475页

作者：谢思晨张伟齐浩李广龙李荣德曲迎东沈阳工业大学材料科学与工程学院辽宁沈阳110870 辽宁省高校轻金属材料与工程重点试验室辽宁沈阳110870

采用非自耗真空电弧熔炼炉制备了Al_(1.2)CrFe_(2)Ni_(2)高熵合金,利用液氮对其进行了不同时间的深冷处理,分析了深冷处理时间对该合金微观组织和性能的影响。结果表明:随着深冷处理时间的延长,Al_(1.2)CrFe_(2)Ni_(2)高熵合金的晶粒尺... 详细信息

采用非自耗真空电弧熔炼炉制备了Al_(1.2)CrFe_(2)Ni_(2)高熵合金,利用液氮对其进行了不同时间的深冷处理,分析了深冷处理时间对该合金微观组织和性能的影响。结果表明:随着深冷处理时间的延长,Al_(1.2)CrFe_(2)Ni_(2)高熵合金的晶粒尺寸先减小后增大,合金晶界处析出B2纳米相,其体积分数呈现先增加后减小的趋势。深冷处理对Al_(1.2)CrFe_(2)Ni_(2)高熵合金具有细晶强化和沉淀强化的作用。当深冷时间为24 h时,合金的硬度、压缩屈服强度和摩擦磨损性能均达到最大值,其硬度和屈服强度分别为HV 607.5和1 259.9 MPa,相比于铸态合金分别提升了18.7%和5.2%,其平均摩擦系数由铸态合金的0.89减小至0.66。

关键词：高熵合金深冷处理压缩性能维氏硬度摩擦磨损性能

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冷应激对奶牛的影响及其防控措施

饲料研究 2024年第1期47卷 143-147页

作者：刘佳兴王纯洁敖日格乐陈浩曹天宇马泽豪姚多任书男内蒙古农业大学兽医学院内蒙古呼和浩特010018 内蒙古农业大学动物科学学院内蒙古呼和浩特010018

奶牛冬季冷应激问题已经成为影响畜牧业健康发展的重要问题之一。冷应激会导致奶牛采食量降低,产奶量和生产繁殖性能下降,严重影响奶牛养殖户的经济效益。内蒙古地处寒冷地区,动物长期处于寒冷环境,受冷应激影响较为常见。为了更具体地... 详细信息

奶牛冬季冷应激问题已经成为影响畜牧业健康发展的重要问题之一。冷应激会导致奶牛采食量降低,产奶量和生产繁殖性能下降,严重影响奶牛养殖户的经济效益。内蒙古地处寒冷地区,动物长期处于寒冷环境,受冷应激影响较为常见。为了更具体地了解冷应激对奶牛生产性能的影响,文章综述了冷应激对奶牛的行为、产奶量、神经内分泌、生化指标、免疫、抗氧化功能、肠道菌群等方面的影响,总结了目前预防奶牛冷应激有效的防控措施,以期为奶牛冷应激预防及缓解工作的进一步研究提供参考。

关键词：冷应激奶牛生化指标生产性能

Towards characterizing bug fixes through dependency-level changes in Apache Java open source projects

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Science China(Information Sciences) 2022年第7期65卷 102-120页

作者： Di CUI Lingling FAN Sen chen Yuanfang CAI Qinghua ZHENG Yang LIU ting LIU School of Computer Science and Technology Xi'an Jiaotong University College of Cyber Science Nankai University College of Intelligence and Computing Tianjin University Department of Computer Science Drexel University School of Computer Science and Engineering Nanyang Technological University School of Cyber Science and Engineering Xi'an Jiaotong University

The complexity and diversity of bug fixes require developers to understand bug fixes from multiple perspectives in addition to fine-grained code changes. The dependencies among files in a software system are an important dimension to inform software quality. Recent studies have revealed that most bug-prone files are always architecturally connected with dependencies, and as one of the best practices in the industry,changes in dependencies should be avoided or carefully made during bug fixing. Hence, in this paper, we take the first attempt to understand bug fixes from the dependencies perspective, which can complement existing code change perspectives. Based on this new perspective, we conducted a systematic and comprehensive study on bug fixes collected from 157 Apache open source projects, involving 140456 bug reports and182621 bug fixes in total. Our study results show that a relatively high proportion of bug fixes(30%) introduce dependency-level changes when fixing the corresponding 33% bugs. The bugs, whose fixes introduce dependency-level changes, have a strong correlation with high priority, large fixing churn, long fixing time,frequent bug reopening, and bug inducing. More importantly, patched files with dependency-level changes in their fixes, consume much more maintenance costs compared with those without these changes. We further summarized three representative patch patterns to explain the reasons for the increasing costs. Our study unveils useful findings based on qualitative and quantitative analysis and also provides new insights that might benefit existing bug prediction techniques. We release a large set of benchmarks and also implement a prototype tool to automatically detect dependency-level changes from bug fixes, which can warn developers and remind them to design a better fix.

关键词： empirical software engineering Empirical Software Engineering software maintenance Software Maintenance Software Evolution software evolution Software Architecture software architecture software design Software Design

电热综合能源系统稳态与区间潮流计算快速解耦新方法

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中国电力 2024年第7期57卷 203-213页

作者：景巍巍王强程好王博岳付昌王沉王文学国网江苏省电力有限公司连云港供电分公司江苏连云港222000 江苏齐天电力建设集团有限公司江苏连云港222000 连云港智源电力设计有限公司江苏连云港222000 河海大学电气与动力工程学院江苏南京211100

综合能源系统稳态潮流计算是后续规划、运行等研究的基础。目前常采用的牛顿-拉夫逊法存在数值稳定性问题,且随着综合能源系统不确定因素增加,研究系统的区间潮流以实现综合能源系统的安全分析和评估变得越来越重要。首先,基于泰勒函数... 详细信息

综合能源系统稳态潮流计算是后续规划、运行等研究的基础。目前常采用的牛顿-拉夫逊法存在数值稳定性问题,且随着综合能源系统不确定因素增加,研究系统的区间潮流以实现综合能源系统的安全分析和评估变得越来越重要。首先,基于泰勒函数一阶展开和二阶展开,推导出热负荷流量和节点温度的解析表达式,该表达式实现了流量与温度的独立求解,无须解方程组即可得到系统稳态潮流。然后,分析流量和温度表达式的函数单调性,结合各热负荷值,确定了热负荷流量和热负荷节点温度的区间潮流解,所提方法在保证计算精度的同时,计算速度快且不存在数值稳定性问题。最后,通过算例分析验证了所提方法的有效性。

关键词：电-热互联综合能源系统稳态潮流区间潮流解耦计算解析式方法

Recent progress in targeted delivery vectors based on biomimetic nanoparticles

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Signal Transduction and Targeted Therapy 2021年第7期6卷 2009-2033页

作者： Li chen Weiqi Hong Wenyan Ren ting Xu Zhiyong Qian Zhiyao He Department of Pharmacy State Key Laboratory of Biotherapy and Cancer CenterNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityChengduSichuanChina Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial TechnologyWest China School of PharmacySichuan UniversityChengduSichuanChina

Over the past decades,great interest has been given to biomimetic nanoparticles(BNPs)since the rise of targeted drug delivery systems and biomimetic *** vectors including cell membranes,extracellular vesicles(EVs),and viruses are considered promising candidates for targeted delivery owing to their biocompatibility and ***,the integration of biological vectors and functional agents,are anticipated to load cargos or camouflage synthetic nanoparticles to achieve targeted *** their excellent intrinsic properties,natural vectors are deliberately modified to endow multiple functions such as good permeability,improved loading capability,and high *** structural modification and transformation of the vectors,they are pervasively utilized as more effective vehicles that can deliver contrast agents,chemotherapy drugs,nucleic acids,and genes to target sites for refractory disease *** review summarizes recent adva门ces in targeted delivery vectors based on cell membranes,EVs,and viruses,highlighting the potential applications of BNPs in the fields of biomedical imaging and therapy industry,as well as discussing the possibility of clinical translation and exploitation trend of these BNPs.

关键词： targeted vectors utilized

经皮卵圆孔未闭介入封堵术后新发心房颤动的单中心临床研究

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泰州职业技术学院学报 2024年第5期24卷 84-86页

作者：王飞鲍婷婷龚梅高琳琳陈各才阮中宝南京医科大学附属泰州人民医院江苏泰州225300

目的探讨卵圆孔未闭(PFO)介入封堵术后1个月新发心房颤动(AF)的发生率并分析术后AF发生的潜在危险因素。方法2022年1月至2023年11月在南京医科大学附属泰州人民医院心内科住院接受PFO封堵术治疗的患者152例,术后1个月利用动态心电图监... 详细信息

目的探讨卵圆孔未闭(PFO)介入封堵术后1个月新发心房颤动(AF)的发生率并分析术后AF发生的潜在危险因素。方法2022年1月至2023年11月在南京医科大学附属泰州人民医院心内科住院接受PFO封堵术治疗的患者152例,术后1个月利用动态心电图监测AF发生率,比较有无新发AF的患者临床特征。结果152例PFO患者均成功进行PFO封堵术,术后1个月随访,8例(5.3%)患者存在AF(AF组),144例患者未发现AF发作(无AF组)。AF组和无AF组在年龄、男性比例、PFO直径、PFO长度及封堵器大小方面存在统计学差异(P<0.05)。单因素和多因素Cox回归分析结果显示,年龄、男性、封堵器大小是PFO后AF发生的独立危险因素(P<0.05)。结论PFO封堵术后存在一定新发AF的风险,年龄较大、男性和较大的封堵器尺寸是PFO术后AF的独立危险因素。

关键词：卵圆孔未闭心房颤动危险因素

A Pyrazine-Based 2D Conductive Metal-Organic Framework for Efficient Lithium Storage

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中国化学:英文版 2023年第14期41卷 1691-1696页

作者： Xiaoxiao Sun Xiaoli Yan Keming Song ting Zhang Zongfan Yang Xi Su Weihua chen Long chen Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistryTianjin UniversityTianjin300072 China College of Chemistry and Green Catalysis Center Zhengzhou UniversityZhengzhouHenan450001 China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchunJilin130012 China

The merits of intrinsic electrical conductivity, high specific surface area, tunable chemical composition and tailor-made properties enable two-dimensional conductive metal-organic frameworks (2D c-MOFs) as promising next-generation electrode materials in the field of energy storage and conversion. Herein, we have designed and synthesized a novel pyrazine-based 2D c-MOF (TPQG-Cu-MOF) bearing extended π-conjugated structure and abundant redox active sites. Thanks to the excellent redox reversibility of pyrazine units and CuO2 units, as well as the insolubility of the rigid framework skeleton, TPQG-Cu-MOF as the cathode material of lithium-ion battery exhibits a reversible specific capacity (150.2 mAh·g–1 at 20 mAh·g–1), good cycling stability (capacity retention of 82.6% after 500 cycles at 1 A·g–1) and excellent rate performance. Comprehensive ex-situ spectroscopic studies revealed the reversible redox activity of pyrazine units and CuO2 units of TPQG-Cu-MOF during the Li+ insertion/extraction process. The deepening fundamental understanding of the structure-property relationship was proposed, which might pave the way for further development of efficient MOF-based energy storage devices.

关键词： Two-dimensional Conductive metal-organic frameworks Pyrazine Energy storage Lithium-ion battery Cathode Stability ComprehensiveSummary