检索结果-南通市图书馆

China Particuology 2007年第6期5卷 414-419页

作者： huaiyuan wang Xin Feng Yijun Shi Xiaohua Lu State Key Laboratory of Materials-oriented Chemical Engineering Nanjing University of Technology Nanjing 210009 China

The friction and wear behavior and mechanism as well as the mechanical properties of polytetrafluoroethylene （PTFE） composites filled with potassium titanate whiskers （PTW） and short carbon fibers （CF） under dry, wet and alkaline conditions were investigated. Experiments indicated that owing to appropriate cooling and boundary lubricating effects, the filled PTFE composites showed much lower frictional coefficient and better wear resistance under alkaline than dry and wet sliding conditions. The wear resistance of carbon-fiber-filled PTFE was much better than that of potassium titanate-whisker-filled PTFE composites in water. Results also showed that the transfer film on counterpart rings was significantly hindered by water and alkali. Hydrophilic-filler-reinforced PTFE composites yield higher wear rate when sliding under water.

关键词： PTFE composites Whiskers Carbon fibers Friction and wear properties Alkaline solution

Synergistic effect of diethylene triamine penta(methylene phosphonic acid) and graphene oxide barrier on anti-scaling and anti-corrosion performance of superhydrophobic coatings

在线全文

学校读者我要写书评

暂无评论

Frontiers of Materials Science 2023年第3期17卷 131-144页

作者： Mingliang Zhu Hongwei Li Ruixia Yuan Huijuan Qian huaiyuan wang College of Chemistry and Chemical Engineering Northeast Petroleum UniversityDaqing 163318China College of Chemical Engineering Daqing Normal UniversityDaqing 163712China

In this study,a novel diethylene triamine penta(methylene phosphonic acid)(DTPMPA)-and graphene oxide(GO)-modified superhydrophobic anodized aluminum(DGSAA)coating was *** obtained coatings were characterized by scan electron microscopy,X-ray diffraction,Fourier transform infrared spectroscopy,and Raman *** immersion in the supersaturated CaCO_(3) solution for 240 h,the scaling mass of the DGSAA coating is only 50%of that of the SAA *** excellent anti-scaling performance of the DGSAA coating comes from three barriers of the air layer,the DTPMPA:Ca^(2+)chelate,and the lamellar GO,as well as the further active anti-scaling of DTPMPA:Ca^(2+)at the coating–solution *** and GO at the surface of the DGSAA coating exhibit an insertion *** the electrochemical impedance spectroscopy measurement,the impedance modulus of the DGSAA coating is three orders-of-magnitude higher than that of the anodized *** synergistic effect of DTPMPA stored in the porous structure of anodized aluminum and the barrier protection of superhydrophobicity and GO contributes to the excellent comprehensive performance of the DGSAA *** research provides a new perspective for designing anti-scaling and anti-corrosion superhydrophobic bi-functional coatings.

关键词： anti-scaling anti-corrosion DTPMPA graphene oxide synergistic effect barrier

The detection method of low-rate DoS attack based on multi-feature fusion

在线全文

学校读者我要写书评

暂无评论

Digital Communications and Networks 2020年第4期6卷 504-513页

作者： Liang Liu huaiyuan wang Zhijun Wu Meng Yue College of Electronics Information and Automation Civil Aviation University of ChinaChina

As a new type of Denial of Service(DoS)attacks,the Low-rate Denial of Service(LDoS)attacks make the traditional method of detecting Distributed Denial of Service Attack(DDoS)attacks useless due to the characteristics of a low average rate and *** features extracted from the network traffic,a new detection approach based on multi-feature fusion is proposed to solve the problem in this *** attack feature set containing the Acknowledge character(ACK)sequence number,the packet size,and the queue length is used to classify normal and LDoS attack *** feature is digitalized and preprocessed to fit the input of the K-Nearest Neighbor(KNN)classifier separately,and to obtain the decision contour *** a posteriori probability in the matrix is fused,and the fusion decision index D is used as the basis of detecting the LDoS *** proved that the detection rate of the multi-feature fusion algorithm is higher than those of the single-based detection method and other algorithms.

关键词： Low-rate denial of service attacks Attack features KNN classifier Multi-feature fusion

A highly stable zinc anode protected by a corrosion inhibitor for seawater-based zinc-ion batteries

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2024年第10期97卷 332-341,I0006页

作者： Bowei Shi Rongwei Meng Xin Jiang Yingxin Liu huaiyuan wang Quanjun Tang Li wang Chen Zhang Guowei Ling Quan-Hong Yang Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy StorageState Key Laboratory of Chemical EngineeringSchool of Chemical Engineering and TechnologyNational Industry-Education Integration Platform of Energy StorageCollaborative Innovation Center of Chemical Science and Engineering(Tianjin)TianjinUniversityTianjin 300072China School of Marine Science and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207FujianChina

The island-based energy storage is of urgent need for the grid construction combined with renewable energy for offshore *** direct use of seawater as a substitute of deionized water shows its great promise for aqueous zinc-ion batteries in such a specific ***,the metal corrosion,dendrite growth,and hydrogen evolution stand out in the harsh seawater *** address these challenges,we proposed a corrosion inhibitor that was effective in the field of metal anti-corrosion,2-phosphonobutane-1,2,4-tricarboxylic acid(PBTCA),to inhibit anode corrosion caused by Cl-and active H_(2)O molecules by forming a stable solid electrolyte interphase(SEI)film in the seawater-based ***,PBTCA can chelate with other cations present in seawater,such as Ca^(2+)and Mg^(2+),thereby preventing the aggregation and precipitation of sparingly soluble *** a current density of5 mA cm^(-2),the seawater-based zinc-ion battery exhibited an exceptional cycle life exceeding 2000 h and maintained a Coulombic efficiency of over 99.6%after 2000 ***,the performance of the Zn||ZVO full battery was significantly enhanced with the addition of *** study provides a simple,low-cost,and efficient approach for making the seawater-based zinc-ion batteries useable.

关键词： Zinc-ion batteries Anti-corrosion Seawater Solid electrolyte interphase

Construction of 3D interconnected boron nitride/carbon nanofiber hybrid network within polymer composite for thermal conductivity improvement

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2023年第16期147卷 165-175页

作者： Yexiang Cui Fei Xu Di Bao Yueyang Gao Jianwen Peng Dan Lin Haolei Geng Xiaosong Shen Yanji Zhu huaiyuan wang School of Chemical Engineering and Technology and State Key Laboratory for Chemical Engineering Tianjin UniversityTianjin 300350China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin Key Laboratory of Chemical Process Safety and Equipment TechnologyTianjin UniversityTianjin 300350China College of Chemistry and Chemical Engineering Northeast Petroleum UniversityDaqing 163318China School of Materials Science and Engineering Tianjin UniversityTianjin 300350China

With the increasing power density and integration of electronic devices,polymeric composites with high thermal conductivity(TC)are in urgent demand for solving heat accumulation ***,the direct introduction of inorganic fillers into a polymer matrix at low filler content usually leads to low TC *** this work,an interconnected three-dimensional(3D)polysulfone/hexagonal boron nitride-carbon nanofiber(PSF/BN-CNF)skeleton was prepared via the salt templated method to address this *** embedding into the epoxy(EP),the EP/PSF/BN-CNF composite presents a high TC of 2.18 W m^(−1) K^(−1) at a low filler loading of 28.61 wt%,corresponding to a TC enhancement of 990%compared to the neat *** enhanced TC is mainly attributed to the fabricated 3D interconnected structure and the efficient synergistic effect of BN and *** addition,the TC of the epoxy composites can be further increased to 2.85 W m^(−1) K^(−1) at the same filler loading through a post-heat treatment of the PSF/BN-CNF *** carbonization at 1500°C,the adhesive PSF was converted into carbonaceous layers,which could serve as a thermally conductive glue to connect the filler network,further decreasing the interfacial thermal resistance and promoting phonon ***,the good heat dissipation performance of the EP/C/BN-CNF composites was directly confirmed by thermal infrared imaging,indicating a bright and broad application in the thermal management of modern electronics and energy fields.

关键词： Thermal conductivity Boron nitride Carbon nanofiber 3D network Epoxy composites

Promoting Effects of Pt on the Catalytic Performance of Supported NiB Amorphous Alloy Catalysts for Benzene Hydrogenation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2011年第4期19卷 698-702页

作者： SONG Hua WU Xianchun wang huaiyuan LI Feng College of Chemistry and Chemical Engineering Northeast Petroleum University Daqing 163318 China Chemical Engineering Dept. Texas A & M University USA

A support(denoted AM) was prepared using pseudo-boehmite and ***-B and NiPtB amorphous catalysts were prepared on the support by the impregnation method followed by chemical reduction with a KBH4 *** the catalysts were characterized by X-ray diffraction(XRD),environment scanning electron microscope(ESEM),inductively coupled plasma(ICP),H2-temperature programmed reduction(H2-TPR),differential thermal analysis(DTA),and *** hydrogenation was used as a probe reaction to evaluate the effect of addition of small quantities of Pt on the NiB/AM *** results show that Pt can promote the reduction of NiO and the formation of active sites,leading to smaller catalyst particles and better dispersion of active metal particles on the *** catalytic activity,sulfur resistance and thermal stability were remarkably improved by Pt doping of the NiB/AM catalyst.

关键词： NiB amorphous alloy benzene hydrogenation Pt doping sulfur resistance

基于集成学习的时间自适应电力系统暂态稳定评估方法

在线全文

学校读者我要写书评

暂无评论

电力系统保护与控制 2022年第24期50卷 112-119页

作者：吴思婕王怀远新能源发电与电能变换重点实验室(福州大学) 福建福州350116

对于电力系统暂态稳定评估而言,在故障清除后的早期阶段,临界样本间的特征差异不明显,预测准确率低。随着时间推移,准确率提高,但难以保证评估的及时性。针对暂态稳定评估的评估准确性与及时性之间的矛盾,提出了基于集成学习的时间自适... 详细信息

对于电力系统暂态稳定评估而言,在故障清除后的早期阶段,临界样本间的特征差异不明显,预测准确率低。随着时间推移,准确率提高,但难以保证评估的及时性。针对暂态稳定评估的评估准确性与及时性之间的矛盾,提出了基于集成学习的时间自适应电力系统暂态稳定评估方法。首先,通过EasyEnsemble算法对不平衡数据进行采样,训练出多个不同评估时刻的集成长短期记忆网络分类器,输出样本在不同评估时刻的稳定性预测结果。其次,将评估时刻进行划分,提出了多阶段阈值分类规则,自适应调整阈值,对样本预测结果进行可信度评估。最后,预测结果评估为不可信的样本交由下一评估时刻的模型继续判断,直到可信度达到阈值后输出。在IEEE 39节点系统的仿真结果表明,所提方法相较于其他时间自适应方法具有更优的评估性能,在样本不平衡的情况下该方法实现了更好的修正效果。

关键词：深度学习暂态稳定评估集成学习时间自适应评估样本不平衡

维普期刊数据库博看期刊

基于代价敏感堆叠变分自动编码器的暂态稳定评估方法

在线全文

学校读者我要写书评

暂无评论

中国电机工程学报 2020年第7期40卷 2213-2220页

作者：王怀远陈启凡福建省新能源发电与电能变换重点实验室(福州大学电气工程与自动化学院) 福建省福州市350108

机器学习算法在训练过程中,难免会遇到样本不平衡的情况,同时,对于电力系统来说稳定样本与不稳定样本的误分类代价是不同的,因此提出一种基于代价敏感堆叠变分自动编码器(stacked variational auto-encoder,SVAE)的电力系统暂态稳定评... 详细信息

机器学习算法在训练过程中,难免会遇到样本不平衡的情况,同时,对于电力系统来说稳定样本与不稳定样本的误分类代价是不同的,因此提出一种基于代价敏感堆叠变分自动编码器(stacked variational auto-encoder,SVAE)的电力系统暂态稳定评估方法。在模型训练过程中,通过改变误分类结果对模型参数调整的权重系数,修正了判别模型在不平衡样本训练过程中的倾向性,并提高了模型全局准确率。在此基础上,进一步提高不稳定样本的权重系数,有效加强了模型对不稳定样本的拟合程度,降低了不稳定样本的误判情况。在IEEE-39节点系统下的仿真结果说明,在不平衡样本情况下,所提方法可以改善判别结果的倾向性;在平衡样本情况下,通过误分类代价的设定可以有效降低不稳定样本的误判情况。

关键词：深度学习堆叠变分自动编码器(SVAE) 暂态稳定性代价敏感不平衡样本

基于堆叠变分自动编码器的电力系统暂态稳定评估方法

在线全文

学校读者我要写书评

暂无评论

电力自动化设备 2019年第12期39卷 134-139页

作者：王怀远陈启凡福州大学电气工程与自动化学院

通过模型的构建和特征量的提取2个方面,提出了一种具有较好抗噪能力的暂态稳定性判别模型。模型的构建采用堆叠变分自动编码器,并在训练过程中引入L2正则化,加强了稳定性判别模型的泛化能力。同时,特征量的提取时刻与传统方法不同,通过... 详细信息

通过模型的构建和特征量的提取2个方面,提出了一种具有较好抗噪能力的暂态稳定性判别模型。模型的构建采用堆叠变分自动编码器,并在训练过程中引入L2正则化,加强了稳定性判别模型的泛化能力。同时,特征量的提取时刻与传统方法不同,通过设定所有发电机最大功角差值的阈值,当系统发展至该阈值时,进行特征量的提取。在IEEE 39节点系统中进行仿真验证,仿真结果表明,采用上述特征量提取方法,大幅降低了稳定性判别模型的误判率,同时设定合理的阈值并不会影响实时控制措施的启动,加强了模型的抗噪能力。

关键词：深度学习堆叠变分自动编码器暂态分析稳定性抗噪能力特征量电力系统

在线全文

学校读者我要写书评

暂无评论

基于响应信息的分散式低频减载方案

电网技术 2019年第8期43卷 2976-2982页

作者：王怀远何培灿温步瀛福州大学电气工程与自动化学院

在部分没有控制中心或通讯装置不健全的区域内,难以获得系统实时的惯量,会给自适应的低频减载方案带来影响。提出一种仅利用本地负荷信息即可整定出最优的自适应切负荷方案,降低了低频减载方案对通讯条件的要求,以及对控制中心的依赖。... 详细信息

在部分没有控制中心或通讯装置不健全的区域内,难以获得系统实时的惯量,会给自适应的低频减载方案带来影响。提出一种仅利用本地负荷信息即可整定出最优的自适应切负荷方案,降低了低频减载方案对通讯条件的要求,以及对控制中心的依赖。首先,根据扰动后负荷的响应信息,提出了实时辨识本地负荷虚拟等值惯量的计算方法。然后根据频率响应模型可以计算本地有功缺额,进而得到在没有控制中心下最优的自适应切负荷方案。在IEEE-39节点系统下孤岛系统进行仿真,验证了本地负荷虚拟等值惯量的实时辨识方法的准确性以及分散式低频减载方案和有效性。

关键词：本地负荷惯量计算频率稳定实时计算功率缺额