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Global dynamics and noise-induced transitions for a two-dimensional panel system in subsonic flow

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Acta Mechanica Sinica 2024年第8期40卷 253-264页

作者： Xiaole Yue Huikang Zhang yongge Li Yong Xu School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710129China MOE Key Laboratory for Complexity Science in Aerospace Northwestern Polytechnical UniversityXi’an710129China

A two-dimensional panel in subsonic flow with stochastic excitation is studied by assuming that the aerodynamic pressure contains random pressure *** on the global properties,the sensitivities of system parameters and noise intensities are ***,the parameter region with multiple coexisting attractors under different dynamic pressures is *** is found that the coexistence of multiple attractors extensively appears and the basin structure may be *** the periodic time history diagrams are calculated by simulating the random pressure fluctuation as Poisson white *** results show that under typical bistable conditions,the noise sensitivity of the subsonic panel system is related to the basin structures and the disposition of the coexisting attractors to the *** transition between two attractors diffuses along the unstable manifold and tends to the position where the basin boundary curvature is relatively *** findings underscore the importance of global analysis in assessing the noise load carrying capacity,which provides some valuable insights into the safety design of subsonic panel systems.

关键词： Global analysis Transition Subsonic panel Multistability

Stationary response of van der Pol oscillator with two kinds of fractional derivatives under Gaussian white noise excitation

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Stationary response of van der Pol oscillator with two kinds...

A H_(4)SiW_(12)O_(40)-catalyzed three-component tandem reaction for the synthesis of 3,3-disubstituted isoindolinones

中国力学大会-2015

作者： yang yongge Xu Wei Gu Xudong Sun Yahui Department of Applied Mathematics Northwestern Polytechnical University Department of Engineering Mechanics Northwestern Polytechnical University State Key Laboratory for Strength and Vibration of Mechanical Structures Xi'an Jiaotong University

This paper investigates the stochastic response of van der Pol oscillator with two kinds of fractional derivatives under Gaussian white noise *** numerical results not only demonstrate the accuracy of the proposed approach but also show that the fractional order the fractional coefficient and the intensity of Gaussian white noise play important roles in the re-

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Chinese Chemical Letters 2024年第1期35卷 233-236页

作者： Yufeng Liu Guodong Zeng Yutao Cheng Lei Chen Yunhai Liu yongge Wei Guoping yang School of Chemistry Biology and Material ScienceJiangxi Province Key Laboratory of Synthetic ChemistryJiangxi Key Laboratory for Mass Spectrometry and InstrumentationEast China University of TechnologyNanchang 330013China Key Lab of Organic Optoelectronics&Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China

A H_(4)SiW_(12)O_(40)-catalyzed three-component tandem reaction of 2-acylbenzoic acids,primary amines and phosphine oxides to form 3,3-disubstituted isoindolinones was *** employing A H_(4)SiW_(12)O_(40)as the catalyst and dimethyl carbonate(DMC)as the solvent,a diverse range of 2-acylbenzoic acid derivatives and primary amines worked well to give the C3-phosphinoyl-functionalized 3,3-disubstituted isoindolinones with the yield range of 61%-87%.Advantages of this transformation include green catalyst and solvent,available starting materials,broad substrate scope,high efficiency and operational simplicity with water as the sole *** strategy achieved an efficient and green molecular fragment assembly to access isoindolinones,which would provide opportunities for the synthesis of potential biologically active molecules in a green manner.

关键词： Polyoxometalates Dehydrative coupling Three-component tandem reaction 3,3-Disubstituted isoindolinones Organic carbonate

POV-based molecular catalysts for highly efficient esterification of alcohols with aldehydes as acylating agents

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Chinese Chemical Letters 2024年第8期35卷 330-334页

作者： Zhikang Wu Guoyong Dai Qi Li Zheyu Wei Shi Ru Jianda Li Hongli Jia Dejin Zang Mirjana Colovic yongge Wei Key Lab of Organic Optoelectronics&Molecular Engineering of Ministry of Education Department of ChemistryTsinghua UniversityBeijing 100084China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100191China Institute of Materia Medica Shandong First Medical University&Shandong Academy of Medical SciencesJi'nan 250117China University of Belgrade VincaInstitute of Nuclear Sciences-National Institute of the Republic of SerbiaDepartment of Physical ChemistryBelgrade 11351Serbia

The selective oxidative esterification of aldehydes with alcohols to the corresponding esters has been one of the hot spots in scientific research and industrial ***,the application of precious metal catalytic systems is limited by their complicated synthetic steps and high *** a highly efficient,green,recyclable selective synthesis method of esters catalyzed by polyoxovanadate(POV)-based molecu-lar catalysts has been developed in this *** results show that supramolecular interaction between POV and 1,3-dibenzylimidazolium bromide(Act_(2)Im)can efficiently convert alcohols and aldehydes to the corresponding esters in high yield under much milder *** insight is also provided based on the control experiments,single crystal X-ray diffraction and cyclic voltammetry studies.

关键词： POV Oxidation Supramolecular Esterification Catalyst

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东鞍山贫赤铁矿石选矿技术研究

金属矿山 2009年第3期38卷 46-49页

作者：杨永革张明薛敏鞍钢集团矿业公司鞍钢集团矿业公司东鞍山烧结厂

分析了东鞍山贫赤铁矿的的工艺类型、矿物学特征、结构构造、可磨特征及原选矿工艺流程的不足,介绍了东鞍山贫赤铁矿选矿新工艺流程的研究和完善过程,并对东鞍山贫赤铁矿选矿新工艺流程的特点进行分析。

关键词：东鞍山贫赤铁矿磁选-阴离子反浮选 SLon高梯度磁选机

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东鞍山难选矿石工艺矿物学研究

金属矿山 2006年第7期35卷 40-43,68页

作者：蒋有义杨永革鞍钢集团鞍山矿业公司

介绍了东鞍山难选矿石含铁绿泥假象赤铁矿石、高亚铁矿石、半氧化矿石和含碳酸盐假象赤铁矿石的矿物组成,并分别分析了其镶嵌特征,对含铁绿泥假象赤铁矿石、高亚铁矿石和半氧化矿石3种难选矿石中矿物的含量、粒度特征进行了研究,对东鞍... 详细信息

介绍了东鞍山难选矿石含铁绿泥假象赤铁矿石、高亚铁矿石、半氧化矿石和含碳酸盐假象赤铁矿石的矿物组成,并分别分析了其镶嵌特征,对含铁绿泥假象赤铁矿石、高亚铁矿石和半氧化矿石3种难选矿石中矿物的含量、粒度特征进行了研究,对东鞍山铁矿石铁矿物粒度变化趋势进行了分析,并提出从选矿上改进难选矿石选别指标的建议。

关键词：含铁绿泥假象赤铁矿石高亚铁矿石半氧化矿石工艺矿物学

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中、新生代吉安盆地沉积环境浅析

华东地质学院学报 2000年第2期23卷 112-115页

作者：杨永革江西地质调查院区调二队江西南昌330201

运用沉积物物理、化学、生物参数 ,分析吉安盆地的沉积环境 ,取得了显著效果 ,为古沉积环境分析积累了经验。在阐述吉安盆地沉积相、古生物及岩石地球化学的基础上 ,着重对古气候、古地理进行了探讨。

关键词：岩相特征古生物特征地球化学特征古环境吉安盆地中生代新生代

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基于时间分割的手写输入系统的用户绩效模型

心理学报 2003年第4期35卷 483-491页

作者：吴昌旭杨群会张侃胡永革杨磊中国科学院心理研究所北京100101 英特尔中国研究院北京100000

为定量估计与提高基于时间分割的手写输入系统用户绩效 ,推导了用户绩效的静态与动态模型。实验一检验与修正了这两个模型 ,并获得整合模型。实验二证明该整合模型能对不同训练水平用户的绩效有较高的解释率。应用该整合模型发现 :当识... 详细信息

为定量估计与提高基于时间分割的手写输入系统用户绩效 ,推导了用户绩效的静态与动态模型。实验一检验与修正了这两个模型 ,并获得整合模型。实验二证明该整合模型能对不同训练水平用户的绩效有较高的解释率。应用该整合模型发现 :当识别正确率RA、输入字数N为定值时 ,修改时间T、单字手写时间WT、分割时间ST、识别时间R这四个因素对任务完成时间D的影响大小次序为WT =ST =R >T ;当这四个因素为定值时 ,RA每提高 1% ,D至少节省 10 0 0ms。

关键词：数学心理模型手写汉字输入系统绩效模型时间分割

气态烃诱导下油气微生物数量及功能基因变化特征

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微生物学报 2017年第1期57卷 43-53页

作者：顾磊梅泽许科伟汤玉平杨帆孙永革浙江大学地球科学系浙江杭州310027 中国石油化工股份有限公司石油勘探开发研究院无锡石油地质研究所江苏无锡214151 江南大学环境与土木工程学院江苏无锡214121

【目的】烃类渗漏是地球化学循环中的自然垂直运移现象。油气微生物勘探技术就是通过检测油气微生物在烃类渗漏条件下形成的异常特征进而预测下伏油气藏。然而,上浮烃类比重小,使得油气微生物丰度小,缺乏对油气藏地表烃类与油气微生物... 详细信息

【目的】烃类渗漏是地球化学循环中的自然垂直运移现象。油气微生物勘探技术就是通过检测油气微生物在烃类渗漏条件下形成的异常特征进而预测下伏油气藏。然而,上浮烃类比重小,使得油气微生物丰度小,缺乏对油气藏地表烃类与油气微生物的深入认识。【方法】本研究在人工模拟环境下,采用培养法和定量PCR对油气微生物数量和油气功能基因的变化特征进行研究。【结果】人工模拟的不同渗漏环境,在一定的驯化培养周期下分别考察甲烷氧化菌和丁烷氧化菌数量变化特征,甲烷氧化菌与丁烷氧化菌在不同烃源中呈现不同的发育情况;同时,在气态烃高浓度阳性对照和微渗漏条件下,油气指示基因pmo A与bom X基因丰度呈现增长现象,然而经过吹脱实验基因丰度仍能指示出曾经发育的油气微生物,在油气微生物勘探检测分析时间尺度上精度高于数量水平的检测。【结论】本研究考察了土壤中油气微生物的数量和功能基因变化特征,为烃类渗漏与油气微生物之间的相关性研究奠定了基础,为油气微生物勘探提供直接实验依据。

关键词：油气微生物勘探油气渗漏定量PCR 气态烃诱导