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Effects of calcination temperature on physicochemical property and ac.ivity of cuSO4/TiO2 ammonia-selec.ive catalytic reduc.ion catalysts

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Journal of Environmental Sciences 2020年第5期32卷 237-245页

作者： yanke Yu Jiali Zhang changwei chen c.i He Jifa Miao Huirong Li Jinsheng chen Department of Environmental Science and Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi'an 710049China Department of chemical Engineering Columbia UniversityNew York 10027USA college of Geology and Environment Xi’an University of Science and TechnologyXi’an 710054China National Engineering Laboratory for VOcs Pollution control Material and Technology University of Chinese Academy of SciencesBeijing 101408China center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

cuSO4/TiO2 catalysts with high catalytic ac.ivity and excellent resistant to SO2 and H2 O,were thought to be promising catalysts used in Selec.ive catalytic reduc.ion of nitrogen oxides by *** performance of catalysts is largely affected by calcination ***,effects of calcination temperature on physicochemical property and catalytic ac.ivity of cuSO4/TiO2 catalysts were investigated in *** samples calcined at different temperatures were prepared first and then physicochemical properties of the catalyst were characterized by N2 adsorption-desorption,X-ray diffrac.ion,thermogravimetric analysis,Raman spectra,Fourier-transform infrared spectroscopy,X-ray photoelectron spectroscopy,temperature-pro grammed desorption of NH3,temperature-programmed reduc.ion of H2 and in situ diffuse reflectance infrared Fourier transform *** revealed that high calcination temperature had three main effects on the ***,sintering and anatase transform into rutile with increase of calcination temperature,causing a decrement of specific surface ***,decomposition of cuSO4 under higher calcination temperature,resulting in disappears of Br(?)nsted acid sites(S-OH),which had an adverse effect on surface ***,cuO from the decomposition of cuSO4 changed surface reducibility of the catalyst and favored the process of NH3 oxidation to nitrogen oxides(NOx).Thus,catalytic ac.ivity of the catalyst calcined under high temperatures(≥600℃)decreased largely.

关键词： calcination temperature Sulfate catalyst Selec.ive catalytic reduc.ion of nitrogen oxides by NH3 Surface acidity NH3 oxidation

Experimental investigation of a Portevin-Le chatelier band in Ni–co-based superalloys in relation toγ’precipitates at 500℃

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Journal of Materials Science & Technology 2020年第14期47卷 35-41页

作者： yanke Liu Yulong c.i chenggang Tian Guoliang Zhang Guoming Han Shihua Fu chuanyong c.i Qingchuan Zhang cAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of ChinaHefei230027China Superalloy Division Institute of Metal ResearchChinese Academy of ScienceShenyang110016China AVic commercial Aircraft Engine co. LtdShanghai201108China Hainan University Haikou570228China

The macroscopically localized deformation behaviors of Ni–co-based superalloys with differentγ’precipitate content were investigated at 500?c and 1×10-4 s-1 via an in situ method namely,digital image correlation(Dic).The Dic results showed that the serrated flow of the stress–strain curves was accompanied by localized deformation of the *** fracture morphology was characterized mainly by transgranular fracture with numerous dimples in the lowγ’content alloy,and intergranular fracture with large fracture sec.ion in the highγ’content *** Portevin–Le chatelier(PLc)effect occurred in the investigated Ni–co-based ***,the localized deformation of the highγ’content alloy was more severe than that of the lowγ’content alloy,and the band width was slightly ***,for the first-time ever,a special propagation feature,namely±60?zigzag bands characterized by head-to-tail connec.ions,was observed in the highγ’content alloy.

关键词： γ’Precipitate Ni–co-based superalloy Dynamic strain aging Portevin–Le chatelier effect Digital image correlation

Deformation mechanisms for a new medium-Mn steel with 1.1 GPa yield strength and 50% uniform elongation

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Journal of Materials Science & Technology 2023年第1期132卷 110-118页

作者： Wei Wang yanke Liu Zihan Zhang Muxin Yang Lingling Zhou Jing Wang Ping Jiang Fuping Yuan Xiaolei Wu State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

A new medium-Mn steel was designed to ac.ieve unprecedented tensile properties,with a yield strength beyond 1.1 GPa and a uniform elongation over 50%.The tensile behavior shows a heterogeneous deforma-tion feature,which displays a yield drop followed by a large Lüders band strain and several Portevin-Le châtelier *** strain hardening mechanisms for excellent tensile properties were ***,non-uniform martensite transformation occurs only within a localized deformation band,and ini-tiation and propagation of every localized deformation band need only a small amount of martensite transformation,which can provide a persistent and complete transformation-induced-plasticity effect dur-ing a large strain ***,geometrically necessary dislocations induced from macroscopic strain gradient at the front of localized deformation band and microscopic strain gradient among various phases provide strong heter-deformation-induced ***,martensite formed by displacive shear trans-formation can inherently generate a high density of mobile screw dislocations,and interstitial c atoms segregated at phase boundaries and enriched in austenite play a vital role in the dislocation multipli-cation due to the dynamic strain aging effect,and these two effects provide a high density of mobile dislocations for strong strain hardening.

关键词： Medium-Mn steel Strain hardening Duc.ility Martensite transformation Strain gradient Mobile dislocations

A Reinforcement Learning Training Acceleration Method Based on Knowledge Distillation

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A Reinforcement Learning Training Acceleration Method Based ...

calibration Method of Magnetometer Based on BP Neural Network

第43届中国控制会议

作者： Zhiwen Wang Rujian Zhang yanke Xu Qing Fei School of Automation Beijing Institute of Technology

The low efficiency of reinforcement learning training has long been a key constraint limiting its prac.ical application in industrial domains. To address this issue, this paper proposes a parallel training framework named Mcic-GA3c. This framework employs knowledge distillation techniques to compress the knowledge of complex target policy models into smallsized behavioral policy networks in real-time. By accelerating the policy predic.ion process through model compression, the training efficiency of the algorithm is enhanced. However, the inconsistency between the behavioral policy and the target policy may result in policy deviation. To mitigate this issue, Mcic-GA3c.introduces importance sampling methods. Simulated experiments are conducted in both Atari games and autonomously designed real-time drone path planning scenarios. Results demonstrate that using compressed behavioral policies for training increases round sampling speed by 17.95%. Furthermore,importance weight correc.ion methods can partially address policy deviation issues, further enhancing the training efficiency of the algorithm. The proposed method also exhibits good training performance in autonomously developed simulation scenarios,validating its effec.iveness and applicability.

关键词： Reinforcement Learning Parallel Training Knowledge Distillation Model compression Path Planning

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Calibration Method of Magnetometer Based on BP Neural Networ...

多晶cu在双向加载下的后继屈服与塑性流动分析

作者： yanke Wang Tao Sheng Liang He Zhaoyang cheng college of Aerospace Science and Engineering National University of Defense Technology

Due to the influence of processing technology and environmental factors, there are errors in attitude measurement with the three-axis magnetometer, and the change of parameters during the operation of the magnetometer in orbit will have a great impact on the measurement accuracy. This paper studies the calibration method of magnetometer based on BP neural network, which reduces the influence of model error on calibration accuracy. Firstly, the error model of the magnetometer and the structural characteristics of the BP neural network are analyzed. Secondly, the number of hidden layers and hidden nodes is optimized. To avoid the problem of slow convergence and low accuracy of basic BP algorithm, this paper uses the Levenberg Marquardt backpropagation training method to improve the training speed and predic.ion accuracy and realizes the on-orbit calibration of magnetometer through online training of the neural network. Finally, the effec.iveness of the method is verified by numerical simulation. The results show that the neural network designed in this paper can effec.ively reduce the measurement error of magnetometer, while the online training can effec.ively reduce the error caused by the change of magnetometer parameters, and reduce the measurement error of magnetometer to less than 10 nT.

关键词： Magnetometer calibration Neural Network Levenberg-Marquardt Method On-Orbit Training

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金属学报 2009年第11期45卷 1370-1377页

作者：石艳柯张克实胡桂娟广西大学工程防灾与结构安全重点实验室南宁530004

采用晶体塑性理论并结合多晶集合体模型来研究多晶cu的塑性变形,用双向加载方式模拟材料的双向应力状态和分段加载路径,得到了材料的初始屈服面及在预剪切和预拉伸2种情况下的后继屈服面.通过对后继屈服面形状及其演化趋势的研究,探讨... 详细信息

采用晶体塑性理论并结合多晶集合体模型来研究多晶cu的塑性变形,用双向加载方式模拟材料的双向应力状态和分段加载路径,得到了材料的初始屈服面及在预剪切和预拉伸2种情况下的后继屈服面.通过对后继屈服面形状及其演化趋势的研究,探讨了用晶体塑性理论分析多晶材料塑性流动规律的方法.结果表明:后继屈服面的形状和是否出现尖角与屈服点的定义有关,同时还与π平面上的预加载方向有关;通过对多晶集合体代表性单元的塑性流动方向与后继屈服面法向的差异进行统计分析,发现塑性流动的正交性不仅与屈服定义相关,也与预加载方向有关.

关键词：多晶cu 晶体塑性后继屈服面塑性流动有限元模拟

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蔗糖酯的酶催化区域选择性合成

有机化学 2003年第8期23卷 770-775页

作者：李延科张淑芬杨锦宗大连理工大学精细化工国家重点实验室大连116012

酶可以区域选择性地合成蔗糖酯 .枯草杆菌等蛋白酶被用来区域选择合成 1′ O 蔗糖酯 ,且通常不接受长链 (大于c12 )脂肪酸作为酰基授体 ,而脂肪酶可催化宽范围的脂肪酸 .除了脂肪酶和蛋白酶外 ,研究发现抗体酶也能区域和立体选择地酰化... 详细信息

酶可以区域选择性地合成蔗糖酯 .枯草杆菌等蛋白酶被用来区域选择合成 1′ O 蔗糖酯 ,且通常不接受长链 (大于c12 )脂肪酸作为酰基授体 ,而脂肪酶可催化宽范围的脂肪酸 .除了脂肪酶和蛋白酶外 ,研究发现抗体酶也能区域和立体选择地酰化蔗糖 .蔗糖二酯、线型蔗糖聚酯都可以通过酶催化区域选择性地合成 .酶催化合成蔗糖酯通常在二甲基甲酰胺、二甲基亚砜和吡啶等有毒溶剂中进行 .近几年来 ,无溶剂条件下酶催化合成蔗糖酯 ,以及用叔丁醇等毒性较小的溶剂代替毒性较大的溶剂的研究 ,也越来越受重视 .

关键词：蔗糖酯酶催化合成区域选择性蛋白酶催化剂脂肪酶蔗糖二酯蔗糖线型聚酯

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狄奥尼索斯的主题学阐释

河南工程学院学报（社会科学版） 2015年第3期30卷 58-64页

作者：陶艳柯复旦大学上海200433

狄奥尼索斯是一个古老的神话原型。它在古希腊罗马时期已有生命自由、迷狂、暴力等多方面的含义。现代文化视域中,德国早期浪漫派正式呼吁狄奥尼索斯的回归,关注其迷狂的一面;随后尼采将酒神精神发扬光大,为狄奥尼索斯在20世纪的复兴埋... 详细信息

狄奥尼索斯是一个古老的神话原型。它在古希腊罗马时期已有生命自由、迷狂、暴力等多方面的含义。现代文化视域中,德国早期浪漫派正式呼吁狄奥尼索斯的回归,关注其迷狂的一面;随后尼采将酒神精神发扬光大,为狄奥尼索斯在20世纪的复兴埋下了伏笔。尼采关注的更多的是狄奥尼索斯形象中受难、迷狂和生命自由等方面。尼采以降,众多理论家的出发点各不相同,但着重凸显狄奥尼索斯形象中的迷狂、生命自由和暴力等方面。

关键词：狄奥尼索斯生命自由迷狂暴力

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大数据存储中数据完整性验证结果的检测算法

计算机研究与发展 2017年第11期54卷 2487-2496页

作者：徐光伟白艳珂燕彩蓉杨延彬黄永锋东华大学计算机科学与技术学院上海201620

云存储作为云计算中最为广泛的应用之一,给用户带来了便利的接入和共享数据的同时,也产生了数据损坏和丢失等方面的数据完整性问题.现有的远程数据完整性验证中都是由可信任的第三方来公开执行数据完整性验证,这使得验证者有提供虚假伪... 详细信息

云存储作为云计算中最为广泛的应用之一,给用户带来了便利的接入和共享数据的同时,也产生了数据损坏和丢失等方面的数据完整性问题.现有的远程数据完整性验证中都是由可信任的第三方来公开执行数据完整性验证,这使得验证者有提供虚假伪造的验证结果的潜在威胁,从而使得数据完整性验证结果不可靠,尤其是当他与云存储提供者合谋时情况会更糟.提出一种数据验证结果的检测算法以抵御来自不可信验证结果的伪造欺骗攻击,算法中通过建立完整性验证证据和不可信检测证据的双证据模式来执行交叉验证,通过完整性验证证据来检测数据的完整性,利用不可信检测证据判定数据验证结果的正确性,此外,构建检测树来确保验证结果的可靠性.理论分析和模拟结果表明:该算法通过改善有效的验证结果来保证验证结果的可靠性和提高验证效率.

关键词：数据完整性验证不可信验证结果验证结果检测双证据检测树