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Nano Research 2024年第9期17卷 8552-8559页

作者： Donghao Zhang Lianxi Si qianqian ren Xintong Yan Shi Hu Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical ***,the electrochemical performance can be further enhanced by fine-tune of the alloy *** binary alloys have been fully studied,the multicomponent alloys are far beyond understanding,which leaves cocktail effect a compromised explanation for the high-entropy *** Pd nanosheet-seeded growth was used to synthesize a Pd-Zn-Cd ternary alloy by accurately controlling the Pd-Zn-Cd molar ratio through adjusting the amount of introduced Cd *** analysis of the crystal phase structure of PdCdZnx and PdZn_(x)Cd_(1-x),the competitive relationship of Zn and Cd in the alloying process with Pd was unveiled:Pd1Cd1 intermetallics(IMC)is thermodynamically favored over Pd_(1)Zn_(1)IMC in the ternary ***,the increased structure stability of PdCd over PdZn does not bring about increased durability in the catalytic ethanol oxidation *** morphology selection of Pd seeds is also crucial for the study,as Pd cubes,Pd tetrahedrons,and Pd octahedrons do not form PdZn in the same *** successful alloying through the seeded growth depends on the maximum diffusion depth of foreign atoms into the seed.

关键词： PdZn alloy seed growth method ethanol oxidation reaction composition control ternary alloying

Distributed Aggregation Algorithms for Mobile Sensor Networks with Group Mobility Model

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Tsinghua Science and Technology 2012年第5期17卷 512-520页

作者： qianqian ren Longjiang Guo Jinghua Zhu Meirui ren Junqing Zhu School of Computer Science and Technology Heilongjiang UniversityHarbin 150080China Key Laboratory of Database and Parallel Computing of Heilongjiang Province Harbin 150080China

In many applications of mobile sensor networks, such as water flow monitoring and disaster rescue, the nodes in the network can move together or separate temporarily. The dynamic network topology makes traditional spanning-tree-based aggregation algorithms invalid in mobile sensor networks. In this paper, we first present a distributed clustering algorithm which divides mobile sensor nodes into several groups, and then propose two distributed aggregation algorithms, Distance-AGG （Aggregation based on Distance）, and Probability-AGG （Aggregation based on Probability）. Both of these two algorithms conduct an aggregation query in three phases： query dissemination, intra-group aggregation, and inter-group aggregation. These two algorithms are efficient especially in mobile networks. We evaluate the performance of the proposed algorithms in terms of aggregation accuracy, energy efficiency, and query delay through ns-2 simulations. The results show that Distance-AGG and Probability-AGG can obtain higher accuracy with lower transmission and query delay than the existing aggregation algorithms.

关键词： mobile sensor networks data aggregation group mobility model distributed algorithms

High-loading Au nanoparticles on carbon by engineering surface charge and specific surface area of substrates

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Progress in Natural Science:Materials International 2024年第4期34卷 637-642页

作者： Xue Deng Siyang Wang qianqian ren Xintong Yan Wenbo Zhao Jianzhong Cui Shi Hu Department of Chemistry School of Science Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University

Energy transition towards net-zero society calls for utilization of renewable power to drive CO2conversion in an efficient electrochemical way. The development of a commercial CO2electrolyzer with positive tech-eco effect calls for active and durable electrocatalysts. High-loading gold on carbon（Au/C） with reduced particle size is the prerequisite for the highly-selective and highly energy-efficient CO production in such a CO2electrolyzer, but a scalable synthetic method is missing. With combined control of ligand, substrate and pH value, Au/C catalysts with particle size within 5 nm and metal loading of 40 wt% and 60 wt% are synthesized on low and high surfacearea carbon, respectively. We also provide a thorough investigation of the effect of the ligand type, surface charge of gold nanoparticles（Au NPs） and surface area of carbon substrate on the loading limit of Au/C.

关键词： Gold nanoparticles High-loading Specific surface area of substrates Surface charge

Ultrathin wavy nanowires of high-entropy alloy as cocktail solution in methanol oxidation reaction

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Progress in Natural Science:Materials International 2023年第2期33卷 225-231页

作者： Songyuan Yuan Xiran Zhu Hui Li Zheng Hu qianqian ren Wenbo Zhao Xiangyang Tang Shi Hu Department of Chemistry School of Science Tianjin Key Laboratory of Molecular Optoelectronic Science Tianjin University Institute of Energy Hefei Comprehensive National Science Center

High entropy alloys(HEAs) with adjustable composition and diverse surface active sites show good catalytic performance of methanol oxidation reaction(MOR). However, the synthesis and morphology control of HEA remains a challenge. Herein, we use a fast co-reduction method to synthesize a series of ultrathin wavy nanowires(WNWs) with an average diameter of 3–5 nm, including Pt-based and Pd-based binary alloys, and HEA with different pairs of immiscible elements. The catalytic properties of Pt Pd Ag Cu Ni WNWs show that the mass activity and stability of Pt Pd Ag Cu Ni WNWs is higher than Pt and Pd WNWs. Meanwhile we explored the cocktail effect among high entropy alloy elements through annealing. The cocktail effect among the metal elements in Pt Pd Ag Cu Ni WNWs provided more active sites with increased metal-metal interactions, thus improving the catalytic efficiency.

关键词： High-entropy alloy Co-reduction Cocktail effect Methanol oxidation reaction

A feature extraction framework for discovering pan-cancer driver genes based on multi-omics data

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Quantitative Biology 2024年第2期12卷 173-181页

作者： Xiaomeng Xue Feng Li Junliang Shang Lingyun Dai Daohui Ge qianqian ren School of Computer Science Qufu Normal UniversityRizhaoChina

The identification of tumor driver genes facilitates accurate cancer diagnosis and treatment,playing a key role in precision oncology,along with gene signaling,regulation,and their interaction with protein *** tackle the challenge of distinguishing driver genes from a large number of genomic data,we construct a feature extraction framework for discovering pan-cancer driver genes based on multi-omics data(mutations,gene expression,copy number variants,and DNA methylation)combined with protein–protein interaction(PPI)*** a network propagation algorithm,we mine functional information among nodes in the PPI network,focusing on genes with weak node information to represent specific cancer *** these functional features,we extract distribution features of pan-cancer data,pan-cancer TOPSIS features of functional features using the ideal solution method,and SetExpan features of pan-cancer data from the gene functional features,a method to rank pan-cancer data based on the average inverse *** features represent the common message of ***,we use the lightGBM classification algorithm for gene *** results show that our method outperforms existing methods in terms of the area under the check precision-recall curve(AUPRC)and demonstrates better performance across different PPI *** indicates our framework’s effectiveness in predicting potential cancer genes,offering valuable insights for the diagnosis and treatment of tumors.

关键词： cancer driver genes feature extraction multi-omics data network propagation pan-cancer

Compressing Information of Target Tracking in Wireless Sensor Networks

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Wireless Sensor Network 2011年第2期3卷 73-81页

作者： Jianzhong Li qianqian ren 不详

Target tracking is a well studied topic in wireless sensor networks. It is a procedure that nodes in the network collaborate in detecting targets and transmitting their information to the base-station continuously, which leads to data implosion and redundancy. To reduce traffic load of the network, a data compressing based target tracking protocol is proposed in this work. It first incorporates a clustering based data gather method to group sensor nodes into clusters. Then a novel threshold technique with bounded error is proposed to exploit the spatial correlation of sensed data and compress the data in the same cluster. Finally, the compact data presentations are transmitted to the base-station for targets localization. We evaluate our approach with a comprehensive set of simulations. It can be concluded that the proposed method yields excellent performance in energy savings and tracking quality.

关键词： Wireless Sensor Networks Target tracking Compressing

信息资源管理一级学科更名背景下研究主题历史演化及未来发展趋势研究

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现代情报 2024年第2期44卷 43-54页

作者：白如江任前前陈鑫山东理工大学信息管理学院山东淄博255049

[目的/意义]为服务国家重大战略需求,抓住学科更名的历史机遇,把握一级学科的整体发展脉络成为构建中国自主的信息资源管理知识体系的重要环节。[方法/过程]以CNKI收录的学科核心期刊文献为数据源,首先采用K-Means聚类算法以及融合TF-ID... 详细信息

[目的/意义]为服务国家重大战略需求,抓住学科更名的历史机遇,把握一级学科的整体发展脉络成为构建中国自主的信息资源管理知识体系的重要环节。[方法/过程]以CNKI收录的学科核心期刊文献为数据源,首先采用K-Means聚类算法以及融合TF-IDF算法和LDA主题模型的分类方法计算最佳主题数量并识别研究主题内容;然后从更名前后的主题强度、主题新颖度、研究主题发展变化情况3个方面深入分析;最后,本研究提出主题词交叉联立的分析方法预测研究主题未来发展方向。[结果/结论]信息资源管理一级学科的更名会刺激新主题的产生与发展,新主题在研究内容、研究范围等方面的拓展反过来丰富了本学科的内涵和外延,对于学科未来的守正创新发展具有一定参考价值。

关键词：信息资源管理学科更名一级学科研究主题发展演变

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环胶州湾河流入海口CDOM吸收光谱特征

环境科学研究 2018年第8期31卷 1407-1416页

作者：任倩倩邹立于格李璐中国海洋大学环境科学与工程学院山东青岛266100 中国海洋大学海洋环境与生态教育部重点实验室山东青岛266100

为深入认识河流对胶州湾水体有机碳的贡献,于2016年4月—2017年2月对环胶州湾河流入海口进行双月采样,通过分析水体中DOC(溶解有机碳)和POC(颗粒有机碳)质量浓度及CDOM(有色溶解有机物)的吸收光谱特征,揭示环胶州湾入海口有机碳的分布特... 详细信息

为深入认识河流对胶州湾水体有机碳的贡献,于2016年4月—2017年2月对环胶州湾河流入海口进行双月采样,通过分析水体中DOC(溶解有机碳)和POC(颗粒有机碳)质量浓度及CDOM(有色溶解有机物)的吸收光谱特征,揭示环胶州湾入海口有机碳的分布特征,辨析CDOM的组成和来源,探讨其与主要环境因素的关系.结果表明:(1)环胶州湾河流入海口DOC和POC质量浓度范围分别为0.98~32.75和0.13~22.40 mg/L,其中李村河口最高,轮渡和大港相对较小.(2)a(355)(CDOM的吸收系数)变化范围为0.23~16.35 m-1,存在明显的季节性差异,与盐度成反比,其分布与DOC和POC基本一致.(3)研究区域水体中,表征CDOM分子组成、来源及芳香化程度的SR[光谱斜率比,Sg(275~295 nm)/Sg(350~400 nm)]和A250 nm/A365 nm存在显著的时空差异.(4)夏季、秋季CDOM的整体分子量水平高于春季、冬季;轮渡、大港、板桥坊河和娄山河SR相对较高,CDOM组成趋向于蛋白类或富里酸类物质.(5)轮渡、大港和镰湾河A250 nm/A365 nm相对较高,类腐殖质的芳香化程度较低,受海源控制;其他河口A250 nm/A365 nm相对较低,CDOM以陆源输入为主,其类腐殖质的芳香化程度较高,结构相对稳定而不易降解.(6)CCA(Canonical Correspond Analysis,典范对应分析)结果表明,DOC与CDOM吸收特性存在较好的相关性,河口CDOM主要来自地表径流,温度和DO是影响CDOM时空分布的主要因素.研究显示,CDOM的组成、降解的难易程度与来源密切相关,秋季生物量丰富,水体中腐殖酸所占比例增大,CDOM芳香度较高,不容易被降解.

关键词：胶州湾河流入海口 CDOM 吸收光谱特征 CCA

基于粒子滤波算法的风力发电塔地震动力响应预测

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振动与冲击 2022年第15期41卷 161-168页

作者：徐亚洲任倩倩于明阳时文浩西安建筑科技大学土木工程学院西安710055

建立有限元分析模型过程中产生的误差和不确定性可导致试验和有限元分析结果之间显著的差异性,量化此类不确定性对结构动力响应预测尤为重要。基于粒子滤波算法对有限元计算结果的不确定性进行量化,提出了一个用于结构动力响应预测的概... 详细信息

建立有限元分析模型过程中产生的误差和不确定性可导致试验和有限元分析结果之间显著的差异性,量化此类不确定性对结构动力响应预测尤为重要。基于粒子滤波算法对有限元计算结果的不确定性进行量化,提出了一个用于结构动力响应预测的概率贝叶斯估计计算框架,并通过风力发电塔振动台试验动力响应观测结果对计算方法的合理性与有效性进行验证。结果表明:随地震波输入幅值的增大,有限元计算结果的误差显著增大,考虑试验观测值修正之后可以显著减小此类不确定性的影响;粒子滤波算法用于结构动力响应预测精度较好,预测值与试验实测值具有很好的一致性;将粒子滤波算法与振动台试验相结合能够对结构动力响应进行有效预测,具有一定的工程应用参考价值。

关键词：贝叶斯估计粒子滤波算法动力响应预测风力发电塔振动台试验

随机近场地震作用下风力发电塔结构振动台试验研究

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振动与冲击 2021年第19期40卷 309-316页

作者：徐亚洲于明阳任倩倩时文浩西安建筑科技大学土木工程学院西安710055

近场脉冲型地震动经常含有较大的加速度峰值及显著的速度脉冲效应,且表现出更明显的不确定性,可能对长周期结构造成严重的破坏。利用近场速度脉冲模型及随机地面运动模型合成了35条基于8度多遇条件下的不同类型随机波样本,按照1/20缩尺... 详细信息

近场脉冲型地震动经常含有较大的加速度峰值及显著的速度脉冲效应,且表现出更明显的不确定性,可能对长周期结构造成严重的破坏。利用近场速度脉冲模型及随机地面运动模型合成了35条基于8度多遇条件下的不同类型随机波样本,按照1/20缩尺比例设计并制作了某2 MW风电塔试验模型,以上述随机地震为试验输入,对模型进行了振动台试验,研究了随机地震作用下风电塔模型结构的响应特性,并对离散性进行了分析。结果表明:模型结构反应表现出显著的离散性,位移反应的变异性沿塔高增加,而剪力反应的变异性随塔高减小;相同幅值脉冲型地震波作用下塔顶加速度、位移及塔底剪力大于无脉冲波,且随着脉冲数量增加,结构反应也呈增大趋势;脉冲型随机波作用下结构加速度响应主要受基本振型控制。

关键词：风力发电塔振动台试验近场随机地震动速度脉冲效应地震反应