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介绍两种微字片的制作方法
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作者 陆德平 《生物学教学》 1995年第7期23-23,共1页
用低倍显微镜观察微字片上的文字符号,可让学生明白:显微镜的成像是上下左右颠倒的,而且实物与物像的运动方向相反,微字片的制作方法简单,现介绍两种: ①剪取邮票或报刊上的微型印刷字,放在干燥洁净的载玻片上,滴一滴香柏油使其透明。... 用低倍显微镜观察微字片上的文字符号,可让学生明白:显微镜的成像是上下左右颠倒的,而且实物与物像的运动方向相反,微字片的制作方法简单,现介绍两种: ①剪取邮票或报刊上的微型印刷字,放在干燥洁净的载玻片上,滴一滴香柏油使其透明。如没有香柏油也可用食用植物油(如豆油、菜油等)代替。待其透明后即可观察。 展开更多
关键词 微字 制作方法 食用植物油 符号 香柏油 左右颠倒 黑白底片 幻灯片 载玻片 方向相反
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运用自媒体平台创建具有“微”字特色的医院文化品牌
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作者 潘炳华 黄凯 +3 位作者 蓝宝龙 黄子倩 农爱玉 李丽华 《现代医院》 2024年第1期30-33,37,共5页
文化的传播需要载体,建设医院特色文化,突出医院特色医院品牌文化的建设,需要得到医护人员和患者的认可,良好的医院文化是增强医院竞争力的重要因素之一,同时能够提高医院在群众中的声誉。自媒体作为我国非常普遍的一种信息流通方式,基... 文化的传播需要载体,建设医院特色文化,突出医院特色医院品牌文化的建设,需要得到医护人员和患者的认可,良好的医院文化是增强医院竞争力的重要因素之一,同时能够提高医院在群众中的声誉。自媒体作为我国非常普遍的一种信息流通方式,基于卫生健康领域自媒体、融媒体快速发展创新的当前,医院应积极建设属于自己的“微”文化发声平台。利用自媒体平台讲述微故事,普及微知识,拍摄微电影,出版微书籍,举办微论坛、微音乐,服务于患者的精神世界,打造医院专属文化。 展开更多
关键词 医院文化 微字品牌 自媒体平台
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数字微镜用于菲涅耳衍射全息显示的理论研究 被引量:8
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作者 李俊昌 宋庆和 桂进斌 《光子学报》 EI CAS CSCD 北大核心 2009年第6期1459-1463,共5页
导出人眼感觉的菲涅耳衍射全息的数字微镜重建场强度表达式.基于数字微镜每显示周期8幅二值图形成灰度图的机制,比较了每周期8幅及256幅二值图方案时菲涅耳衍射全息的显示质量.结果表明,数字微镜显示图像的质量低于数字全息波面重建质量... 导出人眼感觉的菲涅耳衍射全息的数字微镜重建场强度表达式.基于数字微镜每显示周期8幅二值图形成灰度图的机制,比较了每周期8幅及256幅二值图方案时菲涅耳衍射全息的显示质量.结果表明,数字微镜显示图像的质量低于数字全息波面重建质量.存在优化控制数字微镜提高显示图像质量的可能性. 展开更多
关键词 信息光学 全息 微字
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社会语言学视阈下“微”字使用及传播
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作者 李怡岫 《佳木斯职业学院学报》 2020年第8期99-100,共2页
随着互联网技术的提升,微博与微信等网络媒体快速发展,衍生出来一种全新的网络用语——"微-X",已经成为近年来典型的新词。因其受欢迎程度高,具有强大生命力和生产力,"微-X"词越来越引发学者对它的关注。本文首先... 随着互联网技术的提升,微博与微信等网络媒体快速发展,衍生出来一种全新的网络用语——"微-X",已经成为近年来典型的新词。因其受欢迎程度高,具有强大生命力和生产力,"微-X"词越来越引发学者对它的关注。本文首先对网络"微-X"的分类进行简要的分析,随后从社会语言学视域下对影响网络"微-X"通信的因素进行简要的阐述。 展开更多
关键词 社会语言学
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探汉字之源 润语言素养——谈汉字字理微课改进小学语文低段识字教学的探索
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作者 钟镭 《小学时代》 2019年第26期34-35,共2页
汉字是世界上最古老也是最优美的文字之一,也是流传范围最广的一种文字。而对于小学低段学生而言,识字是他们通往祖国灿烂语言文化的船桨。传统的识字教学漠视汉字文化,脱离汉字起源,教学僵化乏味,亟待瓶颈的突破。笔者借助汉字字理微... 汉字是世界上最古老也是最优美的文字之一,也是流传范围最广的一种文字。而对于小学低段学生而言,识字是他们通往祖国灿烂语言文化的船桨。传统的识字教学漠视汉字文化,脱离汉字起源,教学僵化乏味,亟待瓶颈的突破。笔者借助汉字字理微课颠覆传统识字教学,从"复现造字原理,建立认知统一";"绘制思维导图,实现发展提升";"区分同音汉字,强化理解运用"这三方面总结汉字字理微课在识字教学中的操作策略及意义。借助汉字字理微课,带学生探究汉字之源,了解汉字文化,科学识记汉字,润泽语言素养。 展开更多
关键词 思维导图 发展提升
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碳纤维在Ⅰ字梁组合微弯板梁桥加固中的应用
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作者 顼桂莲 《山西建筑》 2004年第7期102-103,共2页
分析了Ⅰ字梁组合微弯板桥开裂破损的主要原因 ,重点阐述了用粘贴碳纤维加固危桥的施工方法和程序 ,并结合某大桥整治加固实例及其试验结论和效益 。
关键词 I梁组合弯板 粘贴碳纤维 危桥加固 荷载 承载能力 混凝土结构
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民族骄子 艺术巨匠——潘美新的石雕与他的微型书画
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作者 夏家骏 《中国人才》 北大核心 1998年第12期25-26,共2页
浙江温州广场路73号小小的亭子间,便是潘美新的起居室与工作室。潘美新,这位年仅48岁的壮年人,个子不高却又有点驼背,颧骨略突却又中耸一个悬胆鼻,布满血丝的面庞还竖立着一根根淡黄的汗毛,稀粗短硬的眉毛下的一双大眼珠,虽然锐光四射... 浙江温州广场路73号小小的亭子间,便是潘美新的起居室与工作室。潘美新,这位年仅48岁的壮年人,个子不高却又有点驼背,颧骨略突却又中耸一个悬胆鼻,布满血丝的面庞还竖立着一根根淡黄的汗毛,稀粗短硬的眉毛下的一双大眼珠,虽然锐光四射却又略显赤黄。 可是,谁能想到:这小小的亭子间里生活和工作的并不起眼的人物。 展开更多
关键词 型书 青田石雕 亭子间 民族 《红楼梦》 冷血动物 新境界 石雕艺术 工艺美术作品 微字
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Design and implementation of digital closed-loop drive control system of a MEMS gyroscope 被引量:5
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作者 王晓雷 李宏生 杨波 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期35-40,共6页
In order to effectively control the working state of the gyroscope in drive mode, the drive characteristics of the micro electromechanical system (MEMS) gyroscope are analyzed in principle. A novel drive circuit for... In order to effectively control the working state of the gyroscope in drive mode, the drive characteristics of the micro electromechanical system (MEMS) gyroscope are analyzed in principle. A novel drive circuit for the MEMS gyroscope in digital closed-loop control is proposed, which utilizes a digital phase-locked loop (PLL) in frequency control and an automatic gain control (AGC) method in amplitude control. A digital processing circuit with a field programmable gate array (FPGA) is designed and the experiments are carried out. The results indicate that when the temperature changes, the drive frequency can automatically track the resonant frequency of gyroscope in drive mode and that of the oscillating amplitude holds at a set value. And at room temperature, the relative deviation of the drive frequency is 0.624 ×10^-6 and the oscillating amplitude is 8.0 ×10^-6, which are 0. 094% and 18. 39% of the analog control program, respectively. Therefore, the control solution of the digital PLL in frequency and the AGC in amplitude is feasible. 展开更多
关键词 micro electromechanical system (MEMS) digitalgyroscope drive frequency phase-locked loop (PLL) oscillating amplitude automatic gain control (AGC)
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“微”字义解
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作者 田玉龙 《汉字文化》 2018年第3期31-33,共3页
"微"字初始义为舞动,此语义与早期原始宗教有紧密关联。商族先公上甲微在作为商部落首领的同时,还具有部落大巫的身份,其发明创始的早期傩舞,成为产生微字初始义的重要文化渊源。其后,微之舞动义逐渐衍生出作为风名的和风义... "微"字初始义为舞动,此语义与早期原始宗教有紧密关联。商族先公上甲微在作为商部落首领的同时,还具有部落大巫的身份,其发明创始的早期傩舞,成为产生微字初始义的重要文化渊源。其后,微之舞动义逐渐衍生出作为风名的和风义与作为舞名的军乐义,并藉由假借等方式而生成诸多新的义项。 展开更多
关键词 微字 义解
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VOLUMETRIC-SWEPT DISPLAY SYSTEM BASED ON HELIX ROTATING SCREEN AND DMD
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作者 岳键 赵晓庚 +2 位作者 邢建芳 潘文平 沈春林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第4期367-371,共5页
Based on the helix rotating screen and the digital micro-mirror device (DMD), the former proto of volumetric-swept display system is improved. The 3-D display system adopting a helix rotating screen to construct an ... Based on the helix rotating screen and the digital micro-mirror device (DMD), the former proto of volumetric-swept display system is improved. The 3-D display system adopting a helix rotating screen to construct an imaging space meliorate the defects, such as the smaller image space, the fewer voxels and the severer voxel overlap dead zone caused by planar rotating screen. DMD with spatial light modular (SLM) technology increases the transmission bandwidth of 3-D data in the voxel activation subsystem and activate multi-voxel once time. The volumetric-swept system based on helix rotating screen and DMD is developed. The experimental results show that the image space, the vision dead zone, the voxels on slice, and the voxel activation capacity of the designed proto are superior to the plane rotating screen system. 展开更多
关键词 true 3-D display volumetric 3-D display volumetric-swept display helix rotating screen digital micro-mirror device (DMD)
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Comparison on the Tolerance of Cruciferous Crops and Leguminous Crops to Microcystin
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作者 刘碧波 吴烨 刘剑彤 《Agricultural Science & Technology》 CAS 2012年第1期198-201,237,共5页
[Objective] To study the differences in the tolerance of leguminous crops and cruciferous crops to microcystin (MC). [Methed] The cruciferous typical crops oilseed rapes, pakchois, cabbages and leguminous typical cr... [Objective] To study the differences in the tolerance of leguminous crops and cruciferous crops to microcystin (MC). [Methed] The cruciferous typical crops oilseed rapes, pakchois, cabbages and leguminous typical crops soybeans, peas and broad beans were selected as the materials to test the effects of MC of differ- ent concentrations on the germination, growth and development of leguminous crops and cruciferous crops. The measurement indicators included germination rate, plant height, chlorophyll, etc. [Result] The MC had great effects on the oilseed rape and pakchois of cruciferous crops, and smaller effects on cabbage, while the leguminous crops were generally not affected. [Conclusion] Leguminous crops are more tolerant to MC than cruciferous crops and more preferential in MC polluted regions. 展开更多
关键词 MICROCYSTIN Cruciferous crops Leguminous crops TOLERANCE DIFFERENCE
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Detection of KRAS G12D in colorectal cancer stool by droplet digital PCR 被引量:1
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作者 Susana Olmedillas-López Dennis César Lévano-Linares +6 位作者 Carmen Laura Aúz Alexandre Luz Vega-Clemente Edurne León Sánchez Alejandro Villagrasa Jaime Ruíz-Tovar Mariano García-Arranz Damián García-Olmo 《World Journal of Gastroenterology》 SCIE CAS 2017年第39期7087-7097,共11页
AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DNA from colorectal cancer (CRC) patients.METHODSIn this study, tumor tissue and stool samples were collected from 70 patients ... AIMTo assess KRAS G12D mutation detection by droplet digital PCR (ddPCR) in stool-derived DNA from colorectal cancer (CRC) patients.METHODSIn this study, tumor tissue and stool samples were collected from 70 patients with stage I-IV CRC diagnosed by preoperative biopsy. KRAS mutational status was determined by pyrosequencing analysis of DNA obtained from formalin-fixed paraffin-embedded (FFPE) tumor tissues. The KRAS G12D mutation was then analyzed by ddPCR in FFPE tumors and stool-derived DNA from patients with this point mutation. Wild-type (WT) tumors, as determined by pyrosequencing, were included as controls; analysis of FFPE tissue and stool-derived DNA by ddPCR was performed for these patients as well.RESULTSAmong the total 70 patients included, KRAS mutations were detected by pyrosequencing in 32 (45.71%), whereas 38 (54.29%) had WT tumors. The frequency of KRAS mutations was higher in left-sided tumors (11 located in the right colon, 15 in the left, and 6 in the rectum). The predominant point mutation was KRAS G12D (14.29%, n = 10), which was more frequent in early-stage tumors (I-IIA, n = 7). In agreement with pyrosequencing results, the KRAS G12D mutation was detected by ddPCR in FFPE tumor-derived DNA, and only a residual number of mutated copies was found in WT controls. The KRAS G12D mutation was also detected in stool-derived DNA in 80% of all fecal samples from CRC patients with this point mutation.CONCLUSIONddPCR is a reliable and sensitive method to analyze KRAS G12D mutation in stool-derived DNA from CRC patients, especially at early stages. This non-invasive approach is potentially applicable to other relevant biomarkers for CRC management. 展开更多
关键词 Droplet digital PCR KRAS STOOL Formalin-fixed paraffin-embedded Pyrosequencing Colorectal cancer
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2-D IMAGE-BASED VOLUMETRIC MODELING FOR PARTICLE OF RANDOM SHAPE 被引量:6
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作者 Chen Ken Larry E. Banta Jiang Gangyi 《Journal of Electronics(China)》 2006年第6期877-881,共5页
In this paper, an approach to predicting randomly-shaped particle volume based on its two- Dimensional (2-D) digital image is explored. Conversion of gray-scale image of the particles to its binary counterpart is fi... In this paper, an approach to predicting randomly-shaped particle volume based on its two- Dimensional (2-D) digital image is explored. Conversion of gray-scale image of the particles to its binary counterpart is first performed using backlighting technique. The silhouette of particle is thus obtained, and consequently, informative features such as particle area, centroid and shape-related descriptors are collected. Several dimensionless parameters are defined, and used as regressor variables in a multiple linear regression model to predict particle volume. Regressor coefficients are found by fitting to a randomly selected sample of 501 panicles ranging in size from 4.75mm to 25ram. The model testing experiment is conducted against a different aggregate sample of the similar statistical properties, the errors of the model-predicted volume of the batch is within ±2%. 展开更多
关键词 Volume estimate Volume modeling Random shape PARTICLES
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Pulsed digital micro-holography of femto-second order by double-wavelength recording 被引量:2
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作者 WANG Ming-wei WANG Xiao-lei ZHAI Hong-chen 《Optoelectronics Letters》 EI 2007年第2期133-135,共3页
Double-wavelength recording used in a pulsed digital micro-holographic system to record ultra-fast processing of the order of femto-second is reported for the first time, where a BBO crystal is used to generate harmon... Double-wavelength recording used in a pulsed digital micro-holographic system to record ultra-fast processing of the order of femto-second is reported for the first time, where a BBO crystal is used to generate harmonic wave of the incident laser wave, and both of the basic and the frequency doubled waves are time-delayed and introduced to a Michelson's interferometer to record two sub-holograms with different spatial frequencies on a single frame of a CCD. In the experiment, an ultrafast dynamic process of air ionization induced by a single femto-second laser pulse is recorded with holography by this system, and both of intensity and phase difference images digitally reconstructed are obtained through Fourier transformation and digital faltering, which show clearly the dynamic process of formation and propagation of the plasma, with a time resolution of the order of femto-second. 展开更多
关键词 脉冲数全息系统 飞秒级激光脉冲 双波长记录 相差 重建
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Improvement of Laih and Yen's multisignature scheme 被引量:2
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作者 谢琪 于秀源 《Journal of Zhejiang University Science》 EI CSCD 2004年第9期1155-1159,共5页
A new attack is proposed to show that a specified group of verifiers can cooperate to forge the signature for any message by secret key substitution due to the leaked secret key or by the group public key adjustment b... A new attack is proposed to show that a specified group of verifiers can cooperate to forge the signature for any message by secret key substitution due to the leaked secret key or by the group public key adjustment because of the renewed members. This paper presents the improvement scheme which overcomes the security weakness of Laih and Yen's scheme. 展开更多
关键词 Digital signature MULTISIGNATURE CRYPTOGRAPHY
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A new method for high precsion instantaneous speedmeasurement of hydraulic system 被引量:1
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作者 LIU Jia-min GU Li-chen SUN Yu 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2019年第4期307-314,共8页
The instantaneous speed of a hydraulic system contains a wealth of operational information,and its accurate extraction is the basis for condition monitoring and fault diagnosis.In order to solve the problem of high ha... The instantaneous speed of a hydraulic system contains a wealth of operational information,and its accurate extraction is the basis for condition monitoring and fault diagnosis.In order to solve the problem of high hardware requirement for instantaneous speed measurement based on data acquisition card,a new method of high precision measurement is proposed.In this method,the time-displacement information of each tooth is obtained from the pulsed square wave signal of the gear disk collected by magnetoelectric sensors.The time-displacement curve is interpolated by the cubic spline interpolation method,and then the instantaneous speed is calculated by the five-point digital differential formula.The experimental results show that the method improves the speed measurement resolution and reduces the quantization error.The high precision instantaneous speed signal can also be acquired by hardware devices with less teeth and low sampling frequency.The related research results provide a theoretical basis and a method for improving the accuracy of instantaneous speed measurement. 展开更多
关键词 instantaneous speed measurement variable speed hydraulic system cubic spline interpolation five-point digital differentiation
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“微”字结构的认知分析
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作者 曹英豪 《吉林广播电视大学学报》 2016年第4期141-142,共2页
最近,以"微"字作语素的词语越来越多,比如:微声、微摇、微观史、微型课程等,这些以"微"字开头的词语所构成的"微"字结构体系有三个方面的特点:一是在形式上,它可以分为"微"字结构、"微观&... 最近,以"微"字作语素的词语越来越多,比如:微声、微摇、微观史、微型课程等,这些以"微"字开头的词语所构成的"微"字结构体系有三个方面的特点:一是在形式上,它可以分为"微"字结构、"微观"结构以及"微型"结构;二是在语义上,它主要表达的是微小义、整体义及角度义;三是在认知上,它的特点主要表现在范畴性、相似性。 展开更多
关键词 结构 概念整合性 相似性 范畴性
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Equilibrium morphology of gas–liquid Janus droplets: A numerical analysis of buoyancy effect 被引量:1
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作者 Shaobin Zhang Helen Yan +2 位作者 Yuhao Geng Ke Wang Jianhong Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第10期2121-2126,共6页
In this article, a theoretical model for predicting the equilibrium morphology of gas–liquid Janus droplets was built. Based on this model, the effects of bubble radius and volume ratio on morphology change was syste... In this article, a theoretical model for predicting the equilibrium morphology of gas–liquid Janus droplets was built. Based on this model, the effects of bubble radius and volume ratio on morphology change was systematically studied. The increase of bubble radius causes the two parts(bubble and oil drop) in Janus droplets tend to merge while the impact of volume ratio is complicated. When volume ratio increases, these two parts firstly tend to merge, then gradually separate. The accuracy of this model was verified by experimental results. 展开更多
关键词 MICROFLUIDICS Gas–liquid–liquid emulsion Janus droplets
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Research on new software compensation method of static and quasi-static errors for precision motion controller
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作者 REN Kun FU Jian-zhong CHEN Zi-chen 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第12期1938-1943,共6页
To reduce mechanical vibrations induced by big errors compensation, a new software compensation method based on an improved digital differential analyzer (DDA) interpolator for static and quasi-static errors of machin... To reduce mechanical vibrations induced by big errors compensation, a new software compensation method based on an improved digital differential analyzer (DDA) interpolator for static and quasi-static errors of machine tools is proposed. Based on principle of traditional DDA interpolator, a DDA interpolator is divided into command generator and command analyzer. There are three types of errors, considering the difference of positions between compensation points and interpolation segments. According to the classification, errors are distributed evenly in data processing and compensated to certain interpolation segments in machining. On-line implementation results show that the proposed approach greatly improves positioning accuracy of computer numerical control (CNC) machine tools. 展开更多
关键词 Static and quasi-static errors Positioning and machining accuracy Digital differential analyzer (DDA) interoolator
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Quantitative characterization of β-solidifying γ-TiAl alloy with duplex structure 被引量:5
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作者 Run-run XU Miao-quan LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第7期1993-2004,共12页
For precise plastic deformation,microstructure control is essential especially for β-solidifying γ-TiAl alloy with duplex structure.Based on stereology,the microstructure of isothermally compressed γ-TiAl alloy was... For precise plastic deformation,microstructure control is essential especially for β-solidifying γ-TiAl alloy with duplex structure.Based on stereology,the microstructure of isothermally compressed γ-TiAl alloy was divided into β_(0) grains,remnant α_(2)/γ lamellar colonies,α_(2) and γ grains.The results show that the volume fraction of β_(0) grains slightly increases in the isothermally compressed γ-TiAl alloy with the increase of height reduction.Meanwhile,the volume fractions of remnant α_(2)/γ lamellar colonies and α_(2) grains decrease.However,the volume fraction of γ grains increases from 64.39% to 78.47%.According to the quantitative results,the α→γ phase transformation was investigated in-depth,and it is found that isothermal compression accelerates the α→γ phase transformation.The first α→γ phase transformation is similar to ledge-controlled transformation,through which remnant α_(2)/γ lamellar colonies finally convert intoγgrains in isothermal compression.The second is achieved by α/γ phase interface immigration. 展开更多
关键词 TiAl alloy STEREOLOGY digital image analysis MICROSTRUCTURE phase transformation
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