检索结果-南通市图书馆

Precipitation Behavior and Mechanical Properties of a 16Cr-25Ni Superaustenitic Stainless Steel Weld Metal During Post-weld Heat Treatment

引用

Acta Metallurgica Sinica(English Letters) 2022年第4期35卷 577-590页

作者： wenbin tian Dong Wu Yiyi Li Shanping Lu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

A 16Cr-25Ni superaustenitic stainless steel weld metal for austenitic stainless steel/ferrite heat-resistance steel dissimilar metal weld was designed and prepared through tungsten inert-gas welding.The precipitate evolution and its correlation with mechanical properties were investigated during post-weld heat treatment(PWHT)at 690℃ for up to 12 h.The primary precipitates in the as-welded weld metal were identified as Mo-rich M6C carbides in the interdendritic region and semicontinuous fine-sized M23C6 carbides along grain boundary.After PWHT,three types of precipitates coexisted in the interdendritic region:primary M6C carbides,newly precipitated Mo-rich M2X carbonitrides and some of the secondary M23C6 carbides.Additionally,mass secondary M23C6 carbides formed and coarsened along grain boundary.No undesirable intermetallic phases formed during the whole period.The M2X and interdendritic M23C6 improved the strength of the weld metal after PWHT,but the elongation and impact toughness degraded,which were mainly owing to the intergranular M23C6 carbides that changed the fracture mode from ductile transgranular mode to mixed mode of transgranular and intergranular fracture.Meanwhile,the coarsening of M2X carbonitrides may lead to the elongation loss during 8 h to 12 h.Evolution of impact toughness was also related to the M2X carbonitrides,which made the crack easier to propagate compared with austenitic matrix and contributed to the decline of impact toughness.However,due to the sluggish precipitation of M2X carbonitrides with longer holding time,the decreasing trend became slow from 4 to 12 h.The results showed that PWHT should be controlled within 8 h to obtain better combination of strength and ductility.

关键词： Superaustenitic stainless steel Weld metal Post-weld heat treatment Precipitate evolution Mechanical properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

单孔排气气泡特征识别与参数提取方法

引用

化工进展 2024年第2期43卷 808-817页

作者：杨志龙田文斌张珍王志英王一伟中国农业大学工学院北京100083 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室石家庄050043 中国科学院力学研究所流固耦合系统力学重点实验室北京100190

气液两相流广泛应用于多种工业领域当中,测量气泡特征参数并进行统计分析可以探究气泡的运动及生长规律,这对相关物理规律和过程控制研究具有重要意义。然而气泡在运动中会发生融合、破碎等现象,导致图像中气泡的重叠粘连,以及拍摄背景... 详细信息

气液两相流广泛应用于多种工业领域当中,测量气泡特征参数并进行统计分析可以探究气泡的运动及生长规律,这对相关物理规律和过程控制研究具有重要意义。然而气泡在运动中会发生融合、破碎等现象,导致图像中气泡的重叠粘连,以及拍摄背景的不均匀性均会对气泡特征数据提取造成较大误差。本文采用高速摄像技术获得了不同液体流速与通气量下的气泡图像,通过对距离变换图像的极值点进行抑制与融合,改进了分水岭算法的前景标记提取方法,实现了气泡的准确分割,进而对分割气泡进行最小二乘椭圆拟合重构,获取了气泡参数。对比分析发现,相较于腐蚀运算和阈值分割提取标记的方法,本文方法准确率分别提高了22.7%与13.6%。通过对气泡特征进行统计分析,发现随着通气量的增加,气泡数量略微增多而平均尺寸显著增大,表明通气量对气泡尺寸有着重要影响。通气量相同,随着来流速度的增加,气泡破碎,气泡的数量增加且平均尺寸减小。

关键词：气液两相流重叠气泡识别气泡特征统计高速摄像

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The study of creation and design of interactive culture in big events——using 2010 Asian Games cheerleading gesture as a case

The study of creation and design of interactive culture in b...

引用

第16届亚洲运动会科学大会

作者： Li Ma wenbin tian Zhengbi Zhang Guangzhou Institute of Physical Education Guangzhou Sport Bureau

Introduction:The study of creation and design of interactive culture in big events will be the basic study between the society and economy development and sport culture transmission area.The related exploration study creates the new angle of view about big events operation and sport journalism communication,it will ex-

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

退火温度对小变形拉拔Cu-0.08Ag合金组织性能的影响

引用

精密成形工程 2024年第6期16卷 164-172页

作者：朱亚丹田文斌齐林蔡佳任玉平李洪晓蒋敏秦高梧东北大学材料科学与工程学院沈阳110819 东北大学材料各向异性与织构教育部重点实验室沈阳110819

目的在分析变形量为25%的小变形拉拔加工Cu-0.08Ag合金组织与性能的基础上,研究不同退火温度对小变形拉拔Cu-0.08Ag合金微观组织、力学性能和导电性能的影响规律,为Cu-Ag合金电磁线漆包工艺的制定提供参考。方法利用电子背散射衍射(EBSD... 详细信息

目的在分析变形量为25%的小变形拉拔加工Cu-0.08Ag合金组织与性能的基础上,研究不同退火温度对小变形拉拔Cu-0.08Ag合金微观组织、力学性能和导电性能的影响规律,为Cu-Ag合金电磁线漆包工艺的制定提供参考。方法利用电子背散射衍射(EBSD)技术对Cu-0.08Ag合金小变形拉拔及200~500℃不同温度退火1 h后的样品进行组织表征,结合显微硬度计、拉伸试验机和电阻计等手段对性能进行综合分析。结果经变形量为25%的小变形拉拔后,Cu-0.08Ag合金等轴晶组织部分晶粒沿变形方向被拉长,和取向占比均增大,应力集中分布在晶粒内,屈服强度提高了270%,而电导率仅下降了4.1%IACS。小变形拉拔Cu-0.08Ag合金的软化温度为350℃。与小变形拉拔态相比,在300℃及以下退火时显微组织和力学性能未发生明显变化,而电导率提升了2.9%IACS。在400℃及以上退火时,无畸变的等轴晶粒取代变形晶粒,并产生大量的退火孪晶,晶粒取向随机分布,力学性能和电导率与小变形拉拔前的相当。结论在300℃以下退火后,小变形拉拔Cu-0.08Ag合金在保持较高屈服强度的同时,其电导率也获得了提升,可获得强度和电导率良好的匹配关系。

关键词： Cu-Ag合金退火温度显微组织力学性能电导率

来源：

维普期刊数据库

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Observation and management of retinal changes related to diving in professional divers

引用

Chinese Medical Journal 2014年第4期127卷 729-733页

作者： Zhou Dan Wei wenbin tian Bei Wang Cong Shi Xuehui Jiao Xuan Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Opthalmology Visual Science Key Laboratory Beijing 100710 China

Background It is very common for professional divers to have damage on the retinas.Severe retinal lesions can profoundly affect athletes＆#39; training efficacy and their daily lives.At present,it is not clear if there is effective preventive action.Thus,in our study,we continuously tracked the ocular changes in athletes and closely monitored the risk factors associated with retinal detachment.Also,we analyzed possible interventions,their associated factors,and efficacies for timely preventions to protect the retina from damage in professional divers.Methods Between 2009 and 2012,a total of 39 professional divers enrolled in follow-up management.The conducted examinations included ocular examination,record screening on retinal lesion,monitoring best-corrected visual acuity,and checking intraocular pressure （lOP） and the scope of retinal lesion.The management included optimizing training methods,taking customized follow-up based on different retinal lesions,laser treatments for definite cases of retinal tear,retinal degeneration caused by retinal layer thinning or vitreous traction,and observing the changes in the scope of retinopathy.Results Every year,the percentage of divers who have various degrees of retinal lesions is between 43.3% and 56.2%.During the 4 years,there were no statistically significant differences in divers＆#39; best-corrected visual acuity and retinal lesions.There were also no statistically significant differences between male and female athletes.However,there were statistically significant differences in lOP during these years.Moreover there were statistically significant differences in IOP and the scope of retinal lesions between platform divers and springboard divers.Conclusions Our management of retinal lesions could be effective to prevent severe retinopathy in professional divers.At the same time,platform divers are more likely to have retinal lesions than springboard divers.

关键词： observation change retinal diving

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Polarization-dependent photoinduced metal–insulator transitions in manganites

引用

Science Bulletin 2024年第2期69卷 183-189页

作者： Lina Deng Weiye Zhang Hanxuan Lin Lifen Xiang Ying Xu Yadi Wang Qiang Li Yinyan Zhu Xiaodong Zhou wenbin Wang Lifeng Yin Hangwen Guo Chuanshan tian Jian Shen State Key Laboratory of Surface Physics Institute for Nanoelectronic Devices and Quantum Computingand Department of PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Quantum Sciences Shanghai 201315China Zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China Shanghai Branch CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum PhysicsShanghai 201315China

In correlated oxides,collaborative manipulation on light intensity,wavelength,pulse duration and polarization has yielded many exotic discoveries,such as phase transitions and novel quantum states.In view of potential optoelectronic applications,tailoring long-lived static properties by light-induced effects is highly desirable.So far,the polarization state of light has rarely been reported as a control parameter for this purpose.Here,we report polarization-dependent metal-to-insulator transition(MIT)in phaseseparated manganite thin films,introducing a new degree of freedom to control static MIT.Specifically,we observed giant photoinduced resistance jumps with striking features:(1)a single resistance jump occurs upon a linearly polarized light incident with a chosen polarization angle,and a second resistance jump occurs when the polarization angle changes;(2)the amplitude of the second resistance jump depends sensitively on the actual change of the polarization angles.Linear transmittance measurements reveal that the origin of the above phenomena is closely related to the coexistence of anisotropic micro-domains.Our results represent a first step to utilize light polarization as an active knob to manipulate static phase transitions,pointing towards new pathways for nonvolatile optoelectronic devices and sensors.

关键词： Metal-insulator phase transitions Polarization of light Electronic phase separation Selective domain controllability

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IbNIEL-mediated degradation of IbNAC087 regulates jasmonic acid-dependent salt and drought tolerance in sweet potato

引用

Journal of Integrative Plant Biology 2024年第2期66卷 176-195页

作者： Xu Li Zhen Wang Sifan Sun Zhuoru Dai Jun Zhang wenbin Wang Kui Peng Wenhao Geng Shuanghong Xia Qingchang Liu Hong Zhai Shaopei Gao Ning Zhao Feng tian Huan Zhang Shaozhen He Key Laboratory of Sweet Potato Biology and Biotechnology Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis&Utilization and Joint Laboratory for International Cooperation in Crop Molecular BreedingMinistry of EducationCollege of Agronomy&BiotechnologyChina Agricultural UniversityBeijing 100193China Sanya Institute of China Agricultural University Sanya 572025China State Key Laboratory of Plant Physiology and Biochemistry National Maize Improvement CenterKey Laboratory of Biology and Genetic Improvement of MaizeBeijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijing 100193China

Sweet potato(Ipomoea batatas[L.]Lam.)is a crucial staple and bioenergy crop.Its abiotic stress tolerance holds significant importance in fully utilizing marginal lands.Transcriptional processes regulate abiotic stress responses,yet the molecular regulatory mechanisms in sweet potato remain unclear.In this study,a NAC(NAM,ATAF1/2,and CUC2)transcription factor,IbNAC087,was identified,which is commonly upregulated in salt-and drought-tolerant germplasms.Overexpression of IbNAC087 increased salt and drought tolerance by increasing jasmonic acid(JA)accumulation and activating reactive oxygen species(ROS)scavenging,whereas silencing this gene resulted in opposite phenotypes.JA-rich IbNAC087-OE(overexpression)plants exhibited more stomatal closure than wild-type(WT)and IbNAC087-Ri plants under NaCl,polyethylene glycol,and methyl jasmonate treatments.IbNAC087 functions as a nuclear transcriptional activator and directly activates the expression of the key JA biosynthesisrelated genes lipoxygenase(IbLOX)and allene oxide synthase(IbAOS).Moreover,IbNAC087 physically interacted with a RING-type E3 ubiquitin ligase NAC087-INTERACTING E3 LIGASE(IbNIEL),negatively regulating salt and drought tolerance in sweet potato.IbNIEL ubiquitinated IbNAC087 to promote 26S proteasome degradation,which weakened its activation on IbLOX and IbAOS.The findings provide insights into the mechanism underlying the IbNIEL-IbNAC087 module regulation of JA-dependent salt and drought response in sweet potato and provide candidate genes for improving abiotic stress tolerance in crops.

关键词： abiotic tolerance IbNAC087 IbNIEL JA sweet potato

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

A Blockchain-Based Access Control Scheme for Reputation Value Attributes of the Internet of Things

引用

Computers, Materials & Continua 2024年第1期78卷 1297-1310页

作者： Hongliang tian Junyuan tian College of Electrical Engineering Northeast Electric Power UniversityJilin132012China

The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data tampering.To address these issues,a blockchain-based IoT reputation value attribute access control scheme is proposed.Firstly,writing the reputation value as an attribute into the access control policy,and then deploying the access control policy in the smart contract of the blockchain system can enable the system to provide more fine-grained access control;Secondly,storing a large amount of resources fromthe Internet of Things in Inter Planetary File System(IPFS)to improve system throughput;Finally,map resource access operations to qualification tokens to improve the performance of the access control system.Complete simulation experiments based on the Hyperledger Fabric platform.Fromthe simulation experimental results,it can be seen that the access control system can achieve more fine-grained and dynamic access control while maintaining high throughput and low time delay,providing sufficient reliability and security for access control of IoT devices.

关键词： Blockchain IoT access control Hyperledger Fabric

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

引用

Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： tian Jing ZHANG Wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial filtering.If the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation effect.To cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range dimension.The principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Transformer and GAN-Based Super-Resolution Reconstruction Network for Medical Images

引用

Tsinghua Science and Technology 2024年第1期29卷 197-206页

作者： Weizhi Du Shihao tian Arts&Sciences College Washington University in St.LouisSt.LouisMO 63130USA Department of Electric and Computing Engineering Cornell UniversityIthacaNY 14850USA

Super-resolution reconstruction in medical imaging has become more demanding due to the necessity of obtaining high-quality images with minimal radiation dose,such as in low-field magnetic resonance imaging(MRI).However,image super-resolution reconstruction remains a difficult task because of the complexity and high textual requirements for diagnosis purpose.In this paper,we offer a deep learning based strategy for reconstructing medical images from low resolutions utilizing Transformer and generative adversarial networks(T-GANs).The integrated system can extract more precise texture information and focus more on important locations through global image matching after successfully inserting Transformer into the generative adversarial network for picture reconstruction.Furthermore,we weighted the combination of content loss,adversarial loss,and adversarial feature loss as the final multi-task loss function during the training of our proposed model T-GAN.In comparison to established measures like peak signal-to-noise ratio(PSNR)and structural similarity index measure(SSIM),our suggested T-GAN achieves optimal performance and recovers more texture features in super-resolution reconstruction of MRI scanned images of the knees and belly.

关键词： super-resolution image reconstruction Transformer generative adversarial network(GAN)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：