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Thermal Fatigue Behavior of Ni_3Al Based Superalloy IC6E

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Chinese Journal of Aeronautics 2006年第B12期19卷 1-4页

作者： ji lei LI Shu-suo HAN Ya-fang jiANG Li-wu School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The thermal fatigue behavior of Ni3Al based superalloy IC6E during the cycles between 900 ℃/1 000 ℃ and the room tempera- ture was investigated. The experimental results indicate that the primary and secondary thermal fatigue cracks initiate inside or round the borides and then spread away along grain boundaries and/or in interdendritic areas. The fracture of borides and their separation from the matrix at interfaces are mainly responsible for the crack initiation and its spreading. At temperatures higher than 1 000 ℃, the grain boundary oxidation combined with cyclic stresses accelerates the crack growth.

关键词： Ni3Al thermal fatigue cast superalloy

Fabrication of solenoid-type microinductor with different magnetic core schemes by MEMS technique

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High Technology Letters 2006年第3期12卷 260-262页

作者：高孝裕 Zhou Yong Chen ji＇ an lei Chong Zhao Xiaolin National Key Laboratory of Nano/Micro Fabrcation Teclmology Key Laboratory for Thin Film and Microfabrication of Ministry of Education Institute of Micro and Nano Science and Teehnology Shanghai Jiaotong University Shanghai 200030 P.R. China

Two micromachined solenoid-type inductors with different electroplated core structures, ellipse and rectangle, were fabricated, tested and compared in order to reach optimum designs for integrated induetoes and transformers. In the process of fabrication, UV-LIGA, dry. etching technique, fine polishing and eleetroplating techniques have been adopted to achieve high performance mieminduetor. Experimental results show that both types of the induetors are characterized by high inductance, Q-factor and low electrical resistance. While the inductance of the inductor with rectangular magnetic core is slightly higher than that with elliptical magnetic core, the quality factor of the latter is larger than that of the former.

关键词： microelectromechanical system (MEMS) inductance quality factor (Q-factor) microinductor magnetic core

Genetic characterization of rarely reported GII.3[P25]norovirus strain detected in patients with acute gastroenteritis in Huzhou,China,2021

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Virologica Sinica 2023年第4期38卷 646-649页

作者： Peng Zhang Deshun Xu Teng Liu Liping Chen lei ji Huzhou Center for Disease Control and Prevention Huzhou313000China Wuxing District Center for Disease Control and Prevention of Huzhou Huzhou313000China

Dear Editor,Noroviruses(NoVs)are now recognized as the leading cause of sporadic and epidemic nonbacterial acute gastroenteritis(AGE)in children and adults worldwide(Glass et al.,2009).NoVs possess a positive-sense,single-stranded RNA genome about 7.6 kb in length,which consists of three open reading frames(ORFs)(Prasad et al.,1999).

关键词： frames characterization gastro

A prediction method of operation trend for large axial-flow fan based on vibration-electric information fusion

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Journal of Central South University 2021年第6期28卷 1786-1796页

作者： GU Zhen-yu ZHU Yao-yao XIANG ji-lei ZENG Yuan College of Automation Chongqing UniversityChongqing 400044China

As the critical equipment,large axial-flow fan(LAF)is used widely in highway tunnels for *** that any malfunction of LAF can cause severe consequences for ***,fault deterioration is suppressed tremendously when an abnormal state is detected in the stage of early ***,the monitoring of the early fault characteristics is very difficult because of the low signal amplitude and system disturbance(or noise).In order to overcome this problem,a novel early fault judgment method to predict the operation trend is proposed in this *** vibration-electric information fusion,the support vector machine(SVM)with particle swarm optimization(PSO),and the cross-validation(CV)for predicting LAF operation states are proposed and ***,the results of the experimental study verify that the performance of the proposed method is superior to that of the contrast models.

关键词： large axial-flow fan early fault state prediction particle swarm optimization

一株耐盐菲降解菌的筛选及其对盐胁迫的生理响应

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生物学杂志 2024年第3期41卷 103-108页

作者：李文静季蕾李天元邢颖娜李琪张强傅晓文齐鲁工业大学(山东省科学院)山东省科学院生态研究所山东省应用微生物重点实验室济南250103

利用高通量筛选技术从胜利油田含油污泥中筛选分离出1株具有耐盐能力的高效菲降解菌,经16S rDNA测序鉴定为假节杆菌,命名为Pseudarthrobacter phenanthrenivorans A-5。探讨菌株A-5对不同程度盐胁迫的响应(分别添加0、1%、3%、5%和7%的N... 详细信息

利用高通量筛选技术从胜利油田含油污泥中筛选分离出1株具有耐盐能力的高效菲降解菌,经16S rDNA测序鉴定为假节杆菌,命名为Pseudarthrobacter phenanthrenivorans A-5。探讨菌株A-5对不同程度盐胁迫的响应(分别添加0、1%、3%、5%和7%的NaCl),结果表明:菌株A-5在不超过3%的盐度下对菲有较高的降解能力(周降解率分别为95.45%、91.20%和79.54%),当NaCl添加量≥5%时,其降解效率显著降低(分别为2.98%和1.56%);随着盐度升高菌株A-5的生长速度逐渐受到抑制,其细胞膜饱和脂肪酸含量随之减少,不饱和脂肪酸含量则随之增加;而四氢嘧啶浓度呈现随盐度升高而增加的趋势。

关键词：油田土壤盐渍化多环芳烃生长曲线膜脂肪酸四氢嘧啶

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美军认知电子战关键技术发展方向分析

通信技术 2024年第3期57卷 299-308页

作者：刘文斌吉磊范平志丁建锋西南交通大学信息科学与技术学院四川成都610756 中国电子科技集团公司第三十研究所四川成都610041

美军认知电子战相关概念发展迅速,也开展了较多的项目研究。为分析其关键技术发展现状并研判其未来发展趋势,从美高校、智库、军事科研机构、厂商4个角度,通过研究论文、报告等公开文献,对美军认知电子战关键技术发展情况,特别是其在机... 详细信息

美军认知电子战相关概念发展迅速,也开展了较多的项目研究。为分析其关键技术发展现状并研判其未来发展趋势,从美高校、智库、军事科研机构、厂商4个角度,通过研究论文、报告等公开文献,对美军认知电子战关键技术发展情况,特别是其在机器学习、人工智能方面的探索进行了深入的分析,对美军认知电子战技术领域研究方向、潜在难题及对应的关键技术思路进行了较为全面的梳理,并从数据、模型、平台、应用等方面给出了启示。

关键词：认知电子战机器学习人工智能电磁频谱作战

冲喷式柔性管缆挖沟机在海底管缆铺设挖沟施工中的应用

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天津科技 2024年第2期51卷 81-84,87页

作者：郑永峻季磊王道明饶云松海洋石油工程股份有限公司天津300451

深水水下管缆的铺设是开发深水油气资源的关键施工作业项目。深水水下挖沟作业具有技术难度大、施工复杂、投资巨大等特点。在深水海域油气开发工程中冲喷式柔性管缆挖沟机应用广泛,因此对其产品性能、实际深水功能测试、挖沟作业工序... 详细信息

深水水下管缆的铺设是开发深水油气资源的关键施工作业项目。深水水下挖沟作业具有技术难度大、施工复杂、投资巨大等特点。在深水海域油气开发工程中冲喷式柔性管缆挖沟机应用广泛,因此对其产品性能、实际深水功能测试、挖沟作业工序、挖沟沟型、挖沟效果等关键技术问题进行分析,经过实践验证,该设备能够独立完成千米级深水域水下挖沟施工。

关键词：冲喷式柔性管缆挖沟机深水油气田海底管缆铺设挖沟沟型

Electroacupuncture promotes peripheral nerve regeneration after facial nerve crush injury and upregulates the expression of glial cell-derived neurotrophic factor

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Neural Regeneration Research 2019年第4期14卷 673-682页

作者： jing Fei Lin Gao Huan-Huan Li Qiong-Lan Yuan lei-ji Li Department of Otorhinolaryngology Head and Neck Surgery Affiliated Hospital of Southwest Medical University Department of Anatomy and Neurobiology Tongji University School of Medicine

The efficacy of electroacupuncture in the treatment of peripheral facial paralysis is known, but the specific mechanism has not been clarified. Glial cell-derived neurotrophic factor(GDNF) has been shown to protect neurons by binding to N-cadherin. Our previous results have shown that electroacupuncture could increase the expression of N-cadherin mRNA in facial neurons and promote facial nerve regeneration. In this study, the potential mechanisms by which electroacupuncture promotes nerve regeneration were elucidated through assessing the effects of electroacupuncture on GDNF and N-cadherin expression in facial motoneurons of rabbits with peripheral facial nerve crush injury. New Zealand rabbits were randomly divided into a normal group(normal control, n = 21), injury group(n = 45) and electroacupuncture group(n = 45). Model rabbits underwent facial nerve crush injury only. Rabbits in the electroacupuncture group received facial nerve injury, and then underwent electroacupuncture at Yifeng(TE17), jiache(ST6), Sibai(ST2), Dicang(ST4), Yangbai(GB14), Quanliao(SI18), and Hegu(LI4; only acupuncture, no electrical stimulation). The results showed that in behavioral assessments, the total scores of blink reflex, vibrissae movement, and position of apex nasi, were markedly lower in the EA group than those in the injury group. Hematoxylin-eosin staining of the right buccinator muscle of each group showed that the cross-sectional area of buccinator was larger in the electroacupuncture group than in the injury group on days 1, 14 and 21 post-surgery. Toluidine blue staining of the right facial nerve tissue of each group revealed that on day 14 post-surgery, there was less axonal demyelination and fewer inflammatory cells in the electroacupuncture group compared with the injury group. Quantitative real time-polymerase chain reaction showed that compared with the injury group, N-cadherin mRNA levels on days 4, 7, 14 and 21 and GDNF mRNA levels on days 4, 7 and 14 were significa

关键词： nerve regeneration facial paralysis electroacupuncture glial cell-derived neurotrophic factor N-cadherin crush injury neuronal apoptosis facial neuron nerve demyelination neural regeneration

How Much Can AI Techniques Improve Surface Air Temperature Forecast?——A Report from AI Challenger 2018 Global Weather Forecast Contest

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Journal of Meteorological Research 2019年第5期33卷 989-992页

作者： lei ji Zaiwen WANG Min CHEN Shuiyong FAN Yingchun WANG Zhiyuan SHEN Institute of Urban Meteorology Beijing100089 Beijing Meteorological Service Beijing 100089 Sinovation Ventures AI Institute Beijing 100080

In August 2018, the Institute of Urban Meteorology(IUM) in Beijing co-organized with Sinovation Ventures a Weather Forecasting Contest(WFC)—one of the AI(artificial intelligence) Challenger Global Contests. The WFC aims to take advantage of the AI techniques to improve the quality of weather forecast. Across the world, more than1000 teams enrolled in the WFC and about 250 teams completed real-time weather forecasts, among which top 5 teams were awarded in the final contest. The contest results show that the AI-based ensemble models exhibited improved skill for forecasts of surface air temperature and relative humidity at 2-m and wind speed at 10-m *** to the IUM operational analog ensemble weather model forecast, the most notable improvements of 24.2%and 17.0% in forecast accuracy for surface 2-m air temperature are achieved by two teams using the AI techniques of time series model, gradient boosting tree, depth probability prediction, and so on. Meanwhile, it is found that reasonable data processing techniques and model composite structure are also important for obtaining better forecasts.

关键词： artificial intelligence(AI) analog ensemble weather forecast surface meteorological elements AI model