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Acta Metallurgica Sinica(English Letters) 2022年第4期35卷 651-661页

作者： qi-Ming wang Yan-Jie Zhang dong Han Xiao-Wu Li Department of Materials Physics and Chemistry School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

Uniaxial tensile tests were carried out at room temperature(RT)and 250℃,respectively,to investigate the effect of shortrange ordering(SRO)on the mechanical properties and deformation micromechanism of fine-grained(FG)Cu–Mn alloys with high stacking fault *** results show that at RT,with the increase in SRO degree,the strength of FG Cu–Mn alloys is improved without a loss of ductility,and corresponding deformation micromechanism is mainly manifested by a decrease in the size of dislocation *** contrast,at a high temperature of 250℃,the SRO degree becomes violently enhanced with increasing Mn content,and the deformation microstructures thus transform from dislocation cells to planar slip bands and even to deformation twins,significantly enhancing the work hardening capacity of the alloys and thus achieving a better strength-ductility synergy of FG Cu–Mn alloys.

关键词： Fine-grained Cu–Mn alloy Short-range ordering Stacking fault energy Temperature Strength-ductility synergy Deformation micromechanism

Phenols/Al(C_(6)F_(5))_(3) Initiation Systems for Cationic Polymerizations of Isobutylene

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Chinese Journal of Polymer Science 2023年第5期41卷 713-719,I0008页

作者： Ling Cai qi-Yuan wang Xin-Li Liu dong-Mei Cui State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Polymer Science and Engineering University of Science and Technology of ChinaHefei 230026China

We report herein the cationic polymerization of isobutylene(IB)under mild conditions is realized with a new binary initiation system generated by simply mixing a Lewis super acid Al(C_(6)F_(5))_(3) and a substituted phenol(RPhOH).Polymers with medium and/or high molecular weights(M_(W)=4.9×10^(4)-27.7×10^(4) g·mol^(-1))can be obtained in toluene and temperatures from-20℃to 0℃.NMR spectrum analysis and DFT sim ulation reveals the in situ generated acidic coordinating complex Ak(C_(6)F_(5))_(3)·RPhOH is the initiating active species,which fu rther tran sformed into the ion-pair[Al(C_(6)F_(5))_(3)ORPh]^(-)[PIB]^(+)of the active intermediates upon growing IB monomers where the counter anion[Al(C_(6)F_(5))_(3)R^(O)Ph]-coordinates to the macrocation via the phenoxy *** catalyst performances are the concert effects of the steric bulkiness and electronics of the counter anion on the coordinating strength to the macrocation,which is significant to the stability of the active species.

关键词： Cationic polymerization Phenols Lewis super acid Polyisobutylene

Solitary Wave Simulated by the Water Column Collapsing Method

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China Ocean Engineering 2022年第3期36卷 395-402页

作者： wang Jin dong Chang-ming LIU qing-jun ZUO qi-hua School of Marine Sciemces Nanjing University of Information Science&TechnologyNanjing 210044China Southern Ocean Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China Nanjing Xinda Institute of Safety and Emergency Management Nanjing 210044China Nanjing Hydraulic Research Institute Nanjing 210029China

Although solitary waves with large ratio of wave height to water depth are difficult to produce in laboratory settings by traditional wave generating methods,a water column collapsing(WCC)method can be *** study uses the WCC method to produce large solitary waves and through a series of experiments,an empirical equation is developed that considers wave height and water depth in addition to water column height and *** solitary waves are studied through wavelet *** from this analysis demonstrate that the ratios between the initial lab-oratory-generated solitary wave and its theoretical counterpart range from 0.2−*** using the results,a new solitary wave generating law is derived and can be applied to future solitary wave laboratory studies.

关键词： water column collapsing solitary wave wavelet spectrum waveform evolution generating law

Comparison between double caliper,imaging logs,and array sonic log for determining the in-situ stress direction:A case study from the ultra-deep fractured tight sandstone reservoirs,the Cretaceous Bashijiqike Formation in Keshen8 region of Kuqa depress

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Petroleum Science 2022年第6期19卷 2601-2617页

作者： Song wang Gui-Wen wang dong Li Xing-Neng Wu Xu Chen qi-qi wang Jun-Tao Cao Yi-Lin Zhang State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum BeijingBeijing102249China College of Geosciences China University of Petroleum BeijingBeijing102249China Research Institute of Petroleum Exploration and Development Tarim Oilfield CompanyCNPCKorla841000XinjiangChina Department of Geological Sciences University of Texas at Austin2275 Speedway Stop C9000AustinTX78712USA

The tight sandstone in the Tarim Basin has the characteristics of large burial depth and development of nature fractures due to concentrated in-situ stress. Identifying the present-day in-situ stress orientation is important in hydrocarbon exploration and development, but also a key scientific question in understanding naturally fractured reservoirs. This paper presents a case study where we integrate various methods using wireline and image-log data, to identify present-day in-situ stress direction of ultra-deep fractured tight sandstone reservoirs, in the Kuqa depression. We discuss the formation mechanism of the elliptical borehole, compares the advantages and applicable conditions of the double caliper method,resistivity image logs and array sonic logs method. The well borehole diameter is measured orthogonally,then the ellipse is fitted, and the in-situ stress orientation is identified by the azimuth of the short-axis borehole, but it fails in the borehole expansion section, the fracture development section and the borehole collapse section. The micro-resistivity image logs method reveals the borehole breakouts azimuth, and also the strike of induced fractures, which are used to determine the orientation of in-situ stress. However, under water-based mud conditions, it’s hard to distinguish natural fractures from induced fractures by image logs. Under oil-based mud conditions, the induced fractures are difficult to identify due to the compromised image quality. As for the sonic log, shear waves will split when passing through an anisotropic formation, shear waves will split during propagation, and the azimuth of fast shear waves is consistent with the orientation of in-situ stress. However, it is usually affected by the anisotropy caused by the excessively fast rotation of the well log tools, so that the azimuth of fast shear wave cannot effectively reflect the orientation of the in-situ stress. Based on comprehensive assessment and comparison, in this paper we

关键词： Fractured tight sandstone In-situ stress Orientation Well logs

Method of Modulation Recognition Based on Combination Algorithm of K-Means Clustering and Grading Training SVM

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China Communications 2018年第12期15卷 55-63页

作者： Faquan Yang Ling Yang dong wang Peihan qi Haiyan wang 无 School of Electrical and Information Engineering Foshan UniversityFoshan 528000China Xinhua College of Sun Yat-sen University Guanzuo 523133China State Key Laboratory of Integrated Service Networks Xidian UniversityXian 710071China

For the existing support vector machine, when recognizing more questions, the shortcomings of high computational complexity and low recognition rate under the low SNR are emerged. The characteristic parameter of the signal is extracted and optimized by using a clustering algorithm, support vector machine is trained by grading algorithm so as to enhance the rate of convergence, improve the performance of recognition under the low SNR and realize modulation recognition of the signal based on the modulation system of the constellation diagram in this paper. Simulation results show that the average recognition rate based on this algorithm is enhanced over 30% compared with methods that adopting clustering algorithm or support vector machine respectively under the low SNR. The average recognition rate can reach 90% when the SNR is 5 dB, and the method is easy to be achieved so that it has broad application prospect in the modulating recognition.

关键词： clustering algorithm feature extraction grading algorithm support vector machine modulation recognition

Study of thermal decoherence of harmonic oscillators

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原子与分子物理学报 2025年第5期42卷 108-114页

作者： LI Jian ZHOU Gao-Liang YAN Zheng-Xin LIU Wei wang Zhao-qi College of Science Xi’an University of Science and TechnologyXi’an 710054China

The thermal decoherence of harmonic oscillators is investigated *** quantum system presented here is a one-dimensional oscillator with angular frequency,which is surrounded by a thermal bath of environmental *** are various environmental oscillators with different angular frequency(below an ultraviolet cutoff).At the beginning,the quantum system is a pure state and the environmental oscillators are in thermodynamic equilibrium with *** a period,the system-environment interactions inspire significant decoherence of the quantum *** decoherence is displayed by explicit calculations of the purity and von Neumann entropy of the quantum *** is worth noting that the decoherence could be significant even in the weak coupling and low temperature case due to the large amount of environmental degrees of *** the decoherence process is inspired between the quantum system and an ordinary thermal environment here,the thermal decoherence result is quite general.

关键词： Quantum decoherence Grand canonical ensemble Oscillators

Texture evolution and mechanical properties of Al-Mg-Si alloys at different intermediate annealing temperatures

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Rare Metals 2019年第10期38卷 937-945页

作者： Yong Li qi-Pan wang Guan-Jun Gao Jia-dong Li Zhao-dong wang Guang-Ming Xu State Key Laboratory of Rolling and Automation Northeastern University

Intermediate annealing treatment produces different effects on the state of particles in Al-Mg-Si alloy sheets,thereby affecting their recrystallization textures and *** improve the formability of the sheets,the effects of different intermediate annealing temperatures on the texture evolution and mechanical properties of these sheets for automotive applications were studied using optical microscope(OM),scanning electron microscope(SEM) and tensile *** results reveal that intermediate annealing temperature has a significant influence on the recrystallization textures and average plastic strain ratio(r).After solution treatment,all the alloy sheets possess similar recrystallization texture components comprising of cubeND {100} and P {011} orientations,whereas a characteristic strong cube-oriented {100} texture is observed only in the alloy annealed at a temperature of 380℃.However,in comparison with the alloy not annealed,and the alloy annealed at 550℃,the alloy annealed at 380℃ possesses a lower average r ***,the relationship between textures and r value was analyzed by using the Taylor full constraints model in this study.

关键词： Al-Mg-Si alloys Intermediate annealing Texture evolution Mechanical property

Detection of Perfect Stealthy Attacks on Cyber-Physical Systems Subject to Measurement Quantizations: A Watermark-Based Strategy

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 114-125页

作者： Yu-Ang wang Zidong wang Lei Zou Bo Shen Hongli dong the College of Information Science and Technology Donghua University the Engineering Research Center of Digitalized Textile and Fashion Technology Ministry of Education IEEE the College of Electrical Engineering and Automation Shandong University of Science and Technology the Department of Computer Science Brunel University London Uxbridge the Sanya Offshore Oil and Gas Research Institute Northeast Petroleum University the Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum University

In this paper, the attack detection problem is investigated for a class of closed-loop systems subjected to unknownbutbounded noises in the presence of stealthy attacks. The measurement outputs from the sensors are quantized before transmission.A specific type of perfect stealthy attack, which meets certain rather stringent conditions, is taken into account. Such attacks could be injected by adversaries into both the sensor-toestimator and controller-to-actuator channels, with the aim of disrupting the normal data flow. For the purpose of defending against these perfect stealthy attacks, a novel scheme based on watermarks is developed. This scheme includes the injection of watermarks(applied to data prior to quantization) and the recovery of data(implemented before the data reaches the estimator).The watermark-based scheme is designed to be both timevarying and hidden from adversaries through incorporating a time-varying and bounded watermark signal. Subsequently, a watermark-based attack detection strategy is proposed which thoroughly considers the characteristics of perfect stealthy attacks,thereby ensuring that an alarm is activated upon the occurrence of such attacks. An example is provided to demonstrate the efficacy of the proposed mechanism for detecting attacks.

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Synthesis and antitumor activity of 9-methyl-10-hydroxycamptothecin

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Chinese Chemical Letters 2008年第8期19卷 918-920页

作者： Sheng wang Yu Yan Li qi dong You Department of Medicinal Chemistry China Pharmaceutical University Nanjing 210009 China

A novel camptothecin analogue, 9-methyl-10-hydroxycamptothecin （4）, was unexpectedly synthesized from 10-hydroxycamptothecin in two steps. The key step included an efficient Mannich-type reaction. The overall yield was 47.2%. An ether analogue of 4, 9-methyl-10-benzylaminomethoxycamptothecin （5）, was also prepared. These new camptothecin analogues were evaluated for in vitro cytotoxicity against four human cancer cell lines, and exhibited more potent antitumor activities than contrals camptothecin and topotecan against several cancer cells.

关键词： Synthesis Camptothecin 10-Hydroxycamptothecin Cytotoxicity

弹目交会条件下爆炸驱动结构体的展开过程研究

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高压物理学报 2025年第1期39卷 1-16页

作者：宁建国汪齐栗建桥北京理工大学爆炸科学与安全防护全国重点实验室北京100081

复杂结构在爆炸驱动作用下的展开是展开型定向战斗部定向过程中的关键问题,对展开过程进行有效控制,有利于战斗部的起爆延时控制和破片利用率提高。针对复杂结构体的展开问题,基于JWL状态方程和第二类拉格朗日方程,从能量守恒出发推导... 详细信息

复杂结构在爆炸驱动作用下的展开是展开型定向战斗部定向过程中的关键问题,对展开过程进行有效控制,有利于战斗部的起爆延时控制和破片利用率提高。针对复杂结构体的展开问题,基于JWL状态方程和第二类拉格朗日方程,从能量守恒出发推导了考虑爆轰产物膨胀过程和对目标命中状态的爆炸驱动展开模型。将驱动展开模型计算结果与文献实验结果进行对比,验证了爆炸驱动展开模型计算结果的准确性。结果表明,基于该模型的理论计算结果与实验结果的一致性较好,能较为精确地预测不同装药量下结构的展开时间;将辅助装药1与辅助装药2的质量比控制在1.5~1.7,结构体展开可达最佳命中姿态,更有利于命中目标。研究成果可充实定向战斗部设计理论,为展开型定向战斗部的设计提供参考。

关键词：爆炸驱动展开姿态展开时间辅助装药定向战斗部

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