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Influences of Asymmetric Reduction Rolling on the Microstructure and Mechanical Properties of AZ91

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Acta Metallurgica Sinica(English Letters) 2018年第7期31卷 673-680页

作者： yi-Quan Zhao Hong-Mei Chen Jing Zhang Ru Ma Yan-Dong Liu yi-nong wang Ling wang Qun Zhang Wei-Gang Li School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China Provincial Key Lab of Advanced Welding Technology Jiangsu University of Science and TechnologyZhenjiang 212003China School of Metallurgy and Materials Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China yingkou Institute of Technology Yingkou 115014China Bayuquan Entry-Exit Inspection and Quarantine Bureau Yingkou 115000China

The influence of asymmetric reduction rolling （ARR） on the microstructure, texture and mechanical properties of AZ91 was investigated. The microstructural characteristics of the AZ91 sheet processed by symmetric roiling （SR） were the twins, intersection of twins and dynamic recrystalization （DRX） grains around the coarse grains and within the twins. However, the amount of twins and DRX grains in ARRed AZ91 was much smaller than that in SRed AZ91. The SRed AZ91 after annealing exhibited fine DRX grains and some coarse grains with a size of ~ 100 pro. The grains in ARRed AZ91 after annealing were much finer and more homogeneous than those in SRed AZ91 after annealing. The intensity of basal texture of ARRed AZ91 after annealing was lower than that of SRed AZ91 rolling after annealing. The average Schmid factor of ARRed AZ91 is 0.34, which is higher than that of SRed AZ91. The yield strength and ultimate tensile strength of the ARRed AZ91 sheet were inCreased to 16.1% and 31.8% compared to SRed AZ91 sheet, from 155 to 180 MPa, and from 220 to 290 MPa, respectively. The improvement of mechanical properties in ARRed AZ91 after annealing was attributed to much finer, more homogeneous DRX grains and weaker basal texture.

关键词： AZ91 Asymmetric reduction rolling. Microstructure Texture Mechanical properties

REINFORCEMENT OF CALCIUM PHOSPHATE CEMENTS WITH PHOSPHORYLATED CHITIN

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Chinese Journal of Polymer Science 2002年第4期20卷 325-332页

作者： Xiao-hong wang Jian-biao Ma yi-nong wang Bin-ling He The State Key Laboratory of Functional Polymer Materials for Adsorption and Separation Institute of Polymer Chemistry Nankai University Tianjin 300071, China Nankai Univ Inst Polymer Chem State Key Lab Funct Polymer Mat Adsorpt & Separat Tianjin 300071 Peoples R China

Phosphorylated chitins (P-chitins) as the additives of calcium phosphate cements (CPCs) were prepared by the phosphorylation of chitin with phosphorus pentoxide in methanesulfonic acid. Their physical properties and effects on CPCs from monocalcium phosphate monohydrate (MCPM) and calcium oxide (CaO) or dicalcium phosphate dihydrate (DCPD) and calcium hydroxide [Ca(OH)(2)] were investigated. Addition of P-chitin (M-w = 2.60 x 10(4); degree of substitution, DS = 0.68) to the liquid phase in amounts up to 3 wt.% for MCPM and CaO cements or 1.5 wt.% for DCPD and Ca(OH)(2) cements could enhance the mechanical strength considerably, while little influence on the setting time was observed. However, further addition of P-chitin will cause no setting.

关键词： phosphorylated chitins calcium phosphate cements mechanical strength setting time

Influence of rolling route on microstructure and mechanical properties of AZ31 magnesium alloy during asymmetric reduction rolling

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Transactions of Nonferrous Metals Society of China 2018年第5期28卷 902-911页

作者： Ru MA Yue LU Ling wang yi-nong wang School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China School of Materials and Metallurgy Northeastern University Shenyang 110819 China

Four different routes of asymmetric reduction rolling were conducted on AZ31 magnesium alloy to investigate their effect on the microstructure evolution and mechanical properties. Route A is the forward rolling; while during routes B and C the sheets are rotated 180o in rolling direction and normal direction, respectively; route D is the unidirectional rolling. The strain states of rolled sheets were analyzed by the finite element method, while the microstructure and texture were observed using optical microscopy, X-ray diffraction and electron back-scattered diffraction techniques, and the mechanical properties were measured by tensile test. The results show that route D produced the largest effective strain. Compared with other samples, sample D exhibited a homogeneous microstructure with fine grains as well as a weak and tilted texture, in corresponding, it performed excellent tensile properties, which suggested that route D was an effective way to enhance the strength and plasticity of AZ31 sheet.

关键词： AZ31 Mg alloy asymmetric reduction rolling rolling route fmite element analysis mechanical properties

Texture evolution and recrystallization behaviors of Cu-Ag alloys subjected to cryogenic rolling

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Transactions of Nonferrous Metals Society of China 2015年第9期25卷 2948-2957页

作者：鲁月马茹王轶农大连理工大学材料科学与工程学院大连116024

The texture evolution and mechanical properties of Cu-Ag alloys subjected to severe plastic deformation at cryogenic temperature（CT） were investigated and the sequent annealing behaviors were also *** with the sheets rolled at room temperature（RT） showing copper texture,the CT-rolled sheets exhibited brass texture which indicated that cross-slip was suppressed at CT,and both the ultimate tensile strength and yield strength of the sheets were *** to the in-situ recrystallization mechanism,recrystallization textures in as-annealed CT-rolled sheets were randomly distributed,while the as-annealed RT-rolled sheets mainly contained cube *** of the rolled and annealed sheets were observed using optical microscopy and electronic back-scatter *** results show that the dynamic recovery was suppressed during CT-rolling and resulted in higher deformation energy ***,the recrystallization of CT-rolled sheets could start at a lower temperature than that of RT-rolled sheet at the same reduction.

关键词： cryogenic rolling copper alloy texture evolution recrystallization behavior

Malicious Document Detection Based on GGE Visualization

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Computers, Materials & Continua 2025年第1期82卷 1233-1254页

作者： Youhe wang yi Sun Yujie Li Chuanqi Zhou Henan Province Key Laboratory of Information Security Information Engineering UniversityZhengzhou450000China

With the development of anti-virus technology,malicious documents have gradually become the main pathway of Advanced Persistent Threat(APT)attacks,therefore,the development of effective malicious document classifiers has become particularly ***,detection methods based on document structure and behavioral features encounter challenges in feature engineering,these methods not only have limited accuracy,but also consume large resources,and usually can only detect documents in specific formats,which lacks versatility and *** address such problems,this paper proposes a novel malicious document detection method-visualizing documents as GGE images(Grayscale,Grayscale matrix,Entropy).The GGE method visualizes the original byte sequence of the malicious document as a grayscale image,the information entropy sequence of the document as an entropy image,and at the same time,the grayscale level co-occurrence matrix and the texture and spatial information stored in it are converted into grayscale matrix image,and fuses the three types of images to get the GGE color *** Convolutional Block Attention Module-EfficientNet-B0(CBAM-EfficientNet-B0)model is then used for classification,combining transfer learning and applying the pre-trained model on the ImageNet dataset to the feature extraction process of GGE *** shown in the experimental results,the GGE method has superior performance compared with other methods,which is suitable for detecting malicious documents in different formats,and achieves an accuracy of 99.44%and 97.39%on Portable Document Format(PDF)and office datasets,respectively,and consumes less time during the detection process,which can be effectively applied to the task of detecting malicious documents in real-time.

关键词： Malicious document visualization EfficientNet-B0 convolutional block attention module GGE image

The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun Wen-Biao Han yi-Yang Guo He wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical Physics & Research Center of Gravitation Lanzhou University International Centre for Theoretical Physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) Center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMRIs). This task is particularly challenging because EMRI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMRI signals for space-borne detectors, achieving a true positive rate(TPR) of 96.9% at a 1% false positive rate(FPR) for signal-to-noise ratio(SNR) from 50 to 100. Especially, the key intrinsic parameters of EMRIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMRI data analysis, enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

具有pH-响应性的聚天冬氨酸类载药胶束的制备和释放能力研究

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高分子学报 2012年第4期22卷 427-432页

作者：于树芳王铮伍国琳王亦农高辉马建标功能高分子材料教育部重点实验室南开大学高分子化学研究所天津300071 天津理工大学化学化工学院天津300191

通过大分子引发剂ω-氨基-α-甲氧基聚乙二醇引发N-羧基-α-氨基环内酸酐开环聚合和水合肼侧基改性,制备了一系列聚乙二醇-聚氨基酸类三嵌段共聚物.其中聚氨基酸链段包括具有酰肼基的聚天冬氨酸衍生物(PAHy),以及疏水性的聚丙氨酸链段.... 详细信息

通过大分子引发剂ω-氨基-α-甲氧基聚乙二醇引发N-羧基-α-氨基环内酸酐开环聚合和水合肼侧基改性,制备了一系列聚乙二醇-聚氨基酸类三嵌段共聚物.其中聚氨基酸链段包括具有酰肼基的聚天冬氨酸衍生物(PAHy),以及疏水性的聚丙氨酸链段.引入具有pH响应性的腙键键合阿霉素,利用键合阿霉素与游离阿霉素之间的π-π叠合作用,在聚合物自组装形成胶束过程中通过化学键合+物理包埋的方式充分负载药物.该胶束以聚丙氨酸链段为核心,以PEG链段为冠层,以PAHy链段为包裹药物的壳层.载药胶束的粒径在170 nm左右.研究不同pH值条件下载药胶束的药物释放能力,随环境pH值的降低药物的释放速率显著增加.

关键词：聚天冬氨酸,腙键,阿霉素,pH-响应性

聚乙二醇-聚谷氨酸-聚丙氨酸三嵌段共聚物的合成及其胶束的pH-响应性药物控制释放

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高分子学报 2012年第6期22卷 599-605页

作者：王铮于树芳顾鑫伍国琳王亦农高辉马建标功能高分子材料教育部重点实验室、南开大学高分子化学研究所天津300071 天津理工大学化学化工学院天津300191

通过大分子引发剂ω-胺基-α-甲氧基聚乙二醇引发N-羧基-α-氨基环内酸酐开环聚合和酸性水解制备了一种具有pH-响应性的三嵌段共聚物聚乙二醇-聚谷氨酸-聚丙氨酸(mPEG-PLGA-PLAA).通过核磁共振、ζ-电势、动态光散射、电子显微镜等手段... 详细信息

通过大分子引发剂ω-胺基-α-甲氧基聚乙二醇引发N-羧基-α-氨基环内酸酐开环聚合和酸性水解制备了一种具有pH-响应性的三嵌段共聚物聚乙二醇-聚谷氨酸-聚丙氨酸(mPEG-PLGA-PLAA).通过核磁共振、ζ-电势、动态光散射、电子显微镜等手段表征了此类三嵌段共聚物的自组装过程及所形成胶束的pH-响应性.使用圆二色谱和红外光谱,分析了胶束结构随环境pH值转变过程中聚氨基酸链段二级结构的变化.以阿霉素作为模型药物,研究了三嵌段共聚物的载药能力和在不同pH条件下的药物释放能力.在碱性条件下,PLGA链段去质子化,链段从疏水性变为亲水性,胶束中间层由于水合作用变得松散,药物释放速率增加;在酸性条件下,PLGA链段质子化,不带电荷,与阿霉素药物分子间的静电相互作用消失.同时,PLGA链段α-螺旋含量增加,形成由链内氢键维持的刚性棒状结构,将链段周围包埋的药物分子"挤出",加速了药物的释放.

关键词：聚天冬氨酸药物释放阿霉素胶束 pH-响应

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Cu2S/CdS太阳电池稳定性的研究概况

太阳能学报 1987年第4期8卷 412-420页

作者：肖亦农王守臣董殿洪袁淑贞中国科学院长春应用化学研究所

本文综述了烧结型和薄膜型Cu2S/CdS太阳电池稳定性的研究概况,报道了这些电池引起衰降的原因,讨论了提高稳定性的一些措施,并对其前景进行了一些推测。

关键词：太阳电池肖亦农 Cu2S/CdS CdS 研究概况