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Influence of binder systems on sintering characteristics, microstructures, and mechanical properties of PcBN composites fabricated by SPS

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Journal of Advanced Ceramics 2022年第2期11卷 321-330页

作者： Shuna CHEN Hengzhong fan Yunfeng SU Wensheng li Jicheng li bing YAN Junjie SONG litian HU Yongsheng ZHANG State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

Cubic boron nitride(cBN)with high hardness,thermal conductivity,wear resistance,and chemical inertness has become the most promising abrasive and machining *** to the difficulty of fabricating pure cBN body,generally,some binders are incorporated among cBN particles to prepare polycrystalline cubic boron nitride(PcBN).Hence,the binders play a critical factor to the performances of PcBN *** this study,the PcBN composites with three binder systems containing ceramic and metal phases were fabricated by spark plasma sintering(SPS)from 1400 to 1700℃.The sintering behaviors and mechanical properties of the composites were *** show that the effect of binder formulas on mechanical properties mainly related to the compactness,mechanical performances,and thermal expansion coefficient of binder phases,which affect the carrying capacity of the composites and the bonding strength between binder phases and cBN *** PcBN composite with SiAlON phase as binder presented optimal flexural strength(465±29 MPa)and fracture toughness(5.62±0.37 MPa·m^(1/2)),attributing to the synergistic effect similar to transgranular and intergranular ***,the excellent mechanical properties can be maintained a comparable level when the temperature even rises to 800℃.Due to the weak bonding strength and high porosity,the PcBN composites with Al_(2)O_(3)–ZrO_(2)(3Y)and Al–Ti binder systems exhibited inferior mechanical *** possible mechanisms to explain these results were also analyzed.

关键词： polycrystalline cubic boron nitride(PcBN) binder system sintering characteristic high temperature mechanical property fracture mechanism

基于IWOA-LSTM算法的预应力钢筋混凝土梁损伤识别

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江苏大学学报（自然科学版） 2025年第1期46卷 105-112,119页

作者：范旭红章立栋杨帆李青郁董凯江苏大学土木工程与力学学院江苏镇江212013 河南省公路工程局集团第二公路工程有限公司河南郑州450015 中国葛洲坝集团第二工程有限公司四川成都610091

为准确识别桥梁结构的损伤程度,制作了桥梁的关键构件——预应力钢筋混凝土梁,进行三点弯曲加载试验.收集了损伤破坏全过程的声发射(AE)信号,通过AE信号参数分析,将梁的损伤破坏过程划分为4个典型阶段.构建了长短时记忆神经网络(LSTM)模... 详细信息

为准确识别桥梁结构的损伤程度,制作了桥梁的关键构件——预应力钢筋混凝土梁,进行三点弯曲加载试验.收集了损伤破坏全过程的声发射(AE)信号,通过AE信号参数分析,将梁的损伤破坏过程划分为4个典型阶段.构建了长短时记忆神经网络(LSTM)模型,根据经验设置LSTM模型的超参数容易导致网络陷入局部最优而影响了分类结果,提出采用Sine混沌映射和自适应权重来改进鲸鱼优化算法(WOA),对LSTM进行超参数寻优.设计了IWOA-LSTM算法模型,训练识别试验梁各损伤阶段的AE信号特征参数.定型网络结构,并识别同种工况下其他梁的AE信号.结果表明:IWOA-LSTM算法模型识别准确率均超过或接近92%,相较于普通LSTM模型,IWOA-LSTM模型识别准确率提高了约7%.

关键词：预应力钢筋混凝土梁声发射损伤识别长短时记忆神经网络改进的鲸鱼优化算法

PROCESS CONTROL OF THE SAND WAVE MIGRATION IN BEIBU GULF OF THE SOUTH CHINA SEA

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Journal of Hydrodynamics 2011年第4期23卷 439-446页

作者： li yong liN Mian JIANG Wen-bing fan Feng-xin Institute of Mechanics Chinese Academy of Sciences Beij ing 100190 China Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China

Based on the environment characteristics of the Beibu Gulf of South China Sea, a quasi-three-dimensional physical model is built. By coupling the bottom boundary layer with the two-dimensional tidal current field near the seabed surface, the quasi-three-dimensional hydrodynamic numerical simulation is carried out. The sand wave migration process is dealt with by coupling the hydrodynamic model with the sediment transport model. The computational results are shown to be in good agreement with the observed data, which indicates that the quasi-three-dimensional physical model can be used to simulate the migration process for small scale sand waves. Then, based on measured data, the evolution of the sand wave migration is investigated. An effective formula is developed to predict the migration rate, in which not only the effects of the environment but also the features of sand waves are considered.

关键词： small scale sand wave sand wave migration quasi-three-dimensional physical model numerical simulation in-situ measurement

Proteomics Identification of Differentially Expressed Leaf Proteins in Response to Setosphaeria turcica Infection in Resistant Maize

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Journal of Integrative Agriculture 2014年第4期13卷 789-803页

作者： ZHANG Xiao-li SI bing-wen fan Cheng-ming li Hong-jie WANG Xiao-ming Institute of Crop Sciences/National Key Facility for Crop Gene Resources and Genetic Improvement Chinese Academy of Agricultural Sciences Beijing Plant Protection Station Institute of Feed Research Chinese Academy of Agricultural Sciences

Northern corn leaf blight （NCLB）, caused by the heterothallic ascomycete fungus Setosphaeria turcica, is a destructive foliar disease of maize and represents a serious threat to maize production worldwide. A comparative proteomic study was conducted to explore the molecular mechanisms underlying the defense responses of the maize resistant line A619 Ht2 to S. turcica race 13. Leaf proteins were extracted from mock and S. turcica-infected leaves after inoculated for 72 h and analyzed for differentially expressed proteins using two-dimensional electrophoresis and mass spectrometry identification. 137 proteins showed reproducible differences in abundance by more than 2-fold at least, including 50 up-regulated proteins and 87 down-regulated proteins. 48 protein spots were successfully identified by MS analysis, which included 10 unique, 6 up-regulated, 20 down-regulated and 12 disappeared protein spots. These identified proteins were classified into 9 functional groups and involved in multiple functions, particularly in energy metabolism （46%）, protein destination and storage （12%）, and disease defense （18%）. Some defense-related proteins were upregulated such as 13-glucosidase, SOD, polyamines oxidase, HSC 70 and PPIases; while the expressions of photosynthesis- and metabolism-related proteins were down-regulated, by inoculation with S. turcica. The results indicated that a complex regulatory network was functioned in interaction between the resistant line A619 Ht2 and S. turcica. The resistance processes of A619 Ht2 mainly resided on directly releasing defense proteins, modulation of primary metabolism, affecting photosyntesis and carbohydrate metabolism.

关键词： maize Setosphaeria turcica Ht2 gene differential proteomics

Atomic Coherent State,Entangled State and Phase Operator for Studying Interference Between Two Bose-Einstein Condensates

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Communications in Theoretical Physics 2008年第11期50卷 1145-1150页

作者： TANG Xu-bing fan Hong-Yi Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China Department of Physics Shanghai Jiao Tong University Shanghai 200030 China

For studying the interference between two Bose-Einstein condensates we introduce the atomic coherentstate(ACS)in the Schwinger bosonic realization along with the phase operator to directly calculate the interferencepattern with steady relative phase cos φ.Eigenstates of the density operator of condensates are classified as A CS is *** entangled state representation is used in some calculations.

关键词： Bose-Einstein condensate atomic coherent state entangled state phase operator

WAPN:a distributed wormhole attack detection approach for wireless sensor networks

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第2期10卷 279-289页

作者： fan-rui KONG Chun-wen li Qing-qing DING Guang-zhao CUI bing-yi CUI Department of Automation. Tsinghua University Beijing 100084. China State Key Lab of Power Systems Departmet of Electrical Engineering Tsinghua University Beijing 100084 China State Key Lab of Informational Electric Apparatus in Henan Zhengzhou 450002 China Department of Phvsics Nanjing University Nanjing 210093 China

As the applications of wireless sensor networks(WSNs) diversify,providing secure communication is emerging as a critical requirement. In this paper,we investigate the detection of wormhole attack,a serious security issue for WSNs. Wormhole attack is difficult to detect and prevent,as it can work without compromising sensor nodes or breaching the encryption key. We present a wormhole attack detection approach based on the probability distribution of the neighboring-node-number,WAPN,which helps the sensor nodes to judge distributively whether a wormhole attack is taking place and whether they are in the in-fluencing area of the attack. WAPN can be easily implemented in resource-constrained WSNs without any additional requirements,such as node localization,tight synchronization,or directional antennas. WAPN uses the neighboring-node-number as the judging criterion,since a wormhole usually results in a significant increase of the neighboring-node-number due to the extra attacking link. Firstly,we model the distribution of the neighboring-node-number in the form of a Bernoulli distribution. Then the model is simplified to meet the sensor nodes' constraints in computing and memory capacity. Finally,we propose a simple method to obtain the threshold number,which is used to detect the existence of a wormhole. Simulation results show that WAPN is effective under the conditions of different network topologies and wormhole parameters.

关键词： Wireless sensor networks (WSNs) Security Wormhole detection

Modeling and verification of comprehensive errors of real-time wear-depth detecting for spherical plain bearing tester

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Journal of Central South University 2017年第3期24卷 533-545页

作者： li Wei HU Zhan-qi YANG Vu-lin fan bing-li ZHOU Hai-li Aviation Key Laboratory of Science and Technology on Generic Technology of Aviation Self-Lubricating Spherical Plain Bearing Yanshan University Qinhuangdao 066004 China

Because of various error factors,the detecting errors in the real-time experimental data of the wear depth affect the accuracy of the detecting *** self-made spherical plain bearing tester was studied,and its testing principle of the wear depth of the spherical plain bearing was ***,the error factors affecting the wear-depth detecting precision were ***,the comprehensive error model of the wear-depth detecting system of the spherical plain bearing was built by the multi-body system theory(MBS).In addition,the thermal deformation of the wear-depth detecting system caused by varying the environmental temperature was ***,according to the above experimental parameters,the thermal errors of the related parts of the comprehensive error model were calculated by *** results show that the difference between the simulation value and the experimental value is less than 0.005 mm,and the two values are *** correctness of the comprehensive error model is verified under the thermal error experimental conditions.

关键词： spherical plain bearing tester self-lubricating spherical plain bearing wear depth multi-body system theory comprehensive error model thermal error

Prognostic effect of excessive chemotherapy cycles for stage Ⅱ and Ⅲ gastric cancer patients after D2 + gastrectomy

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World Journal of Gastrointestinal Surgery 2023年第1期15卷 32-48页

作者： Yi-fan li Wen-bing Zhang Yu-Ye Gao Department of General Surgery Shanxi Province Cancer HospitalTaiyuan 030013Shanxi ProvinceChina Endoscopy Center Shanxi Province Cancer HospitalTaiyuan 030013Shanxi ProvinceChina Department of Gastrointestinal Surgery Peking University Cancer Hospital and InstituteBeijing 00010China

BACKGROUND According to relevant investigation and analysis,there are few research studies on the effect of excessive chemotherapy cycles after D2 gastrectomy on the survival of patients with gastric *** To determine whether excessive chemotherapy cycles provide extra survival benefits,reduce recurrence rate,and improve survival rate in patients with stage Ⅱ or Ⅲ gastric *** We analyzed and summarized 412 patients with stage Ⅱ gastric cancer and 902 patients with stage Ⅲ gastric cancer who received D2 gastrectomy plus adjuvant chemotherapy or neoadjuvant *** and comparison at a ratio of 1:1 is aimed at reducing realistic baseline differences(n=97 in each group of stage Ⅱ,n=242 in each group of stage Ⅲ).Progression-free survival,overall survival and recurrence were the main outcome *** When the propensity score was matched,the baseline features of stage Ⅱ and Ⅲ gastric cancer patients were similar between the two *** a series of investigations,Kaplan-Meier found that the progression-free survival and overall survival of stage Ⅱ and Ⅲ gastric cancer patients were consistent between the two *** local metastasis rate(P=0.002),total recurrence rate(Plity in the<9 cycles *** Overall,≥9 chemotherapy cycles is not recommended for patients with stage Ⅱ and stage Ⅲ gastric cancer because it has an insignificant role in the prognosis of gastric ***,for patients with stage Ⅲ gastric cancer,≥9 cycles of chemotherapy was shown to significantly decrease recurrence.

关键词： Gastric cancer Propensity score matching Chemotherapy cycles Overall survival Progressionfree survival Recurrence

我们都是“同时代人”——如何建构当代文学价值共同体的反思

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当代文坛 2025年第1期 77-81页

作者：丁帆南京大学文学院

“同时代人”是一个超越年龄、时空的广义内涵的存在,它打破了生理年龄和朝代更迭,以代际划分的“同时代人”的陈见,用一种具有深刻和前瞻意义的理念,聚合成一种具有“当代性”的切分方法,以跨越代际的共同价值观来重塑“同时代人”群体... 详细信息

“同时代人”是一个超越年龄、时空的广义内涵的存在,它打破了生理年龄和朝代更迭,以代际划分的“同时代人”的陈见,用一种具有深刻和前瞻意义的理念,聚合成一种具有“当代性”的切分方法,以跨越代际的共同价值观来重塑“同时代人”群体,以此作为解决创作困囿和批评迷惘的突破口。“我们可以使自己成为这些文本的同时代人”的命题,才是需要正视的最本质的问题所在。当下的“同时代人”,既要以史为鉴,从历史的“同时代人”的思想宝库中,汲取属于我们这个时代的相对统一价值观,同时还要引领更多能够聚合在同一价值观下的“同时代人”,发出对整个世界的批判性哲学诘问,这也是改“未完成的现代性”为“当代性”关键词的理由,希冀由此而触及对当代文学治史观念的一种新观念和新方法,在“同时代人”旗帜下,建构起一种基本的人文价值观和学术守则。

关键词： “同时代人” “当代性” 文学价值共同体 “真理性”