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A review of nondestructive examination technology for polyethylene pipe in nuclear power plant

Frontiers of Mechanical Engineering 2018年第4期13卷 535-545页

作者： jinyang zheng Yue ZHANG Dongsheng HOU Yinkang QIN Weican GUO Chuck ZHANG Jianfeng SHI Institute of Process Equipment Zhejiang University Hangzhou 310027 China Zhejiang Provincial Special Equipment Inspection and Research Institute Hangzhou 310027 China Georgia Tech Manufacturing Institute Georgia Institute of TechnologyAtlanta GA 30332 USA

Polyethylene （PE） pipe, particularly high- density polyethylene （HDPE） pipe, has been successfully utilized to transport cooling water for both non-safety- and safety-related applications in nuclear power plant （NPP）. Though ASME Code Case N755, which is the first code case related to NPP HDPE pipe, requires a thorough nondestructive examination （NDE） of HDPE joints. However, no executable regulations presently exist because of the lack of a feasible NDE technique for HDPE pipe in NPP. This work presents a review of current developments in NDE technology for both HDPE pipe in NPP with a diameter of less than 400 mm and that of a larger size. For the former category, phased array ultrasonic technique is proven effective for inspecting typical defects in HDPE pipe, and is thus used in Chinese national standards GB/T 29460 and GB/T 29461. A defect- recognition technique is developed based on pattern recognition, and a safety assessment principle is summa- rized from the database of destructive testing. On the other hand, recent research and practical studies reveal that in current ultrasonic-inspection technology, the absence of effective ultrasonic inspection for large size was lack of consideration of the viscoelasticity effect of PE on acoustic wave propagation in current ultrasonic inspection technology. Furthermore, main technical problems were analyzed in the paper to achieve an effective ultrasonic test method in accordance to the safety and efficiency requirements of related regulations and standards. Finally, the development trend and challenges of NDE test technology for HDPE in NPP are discussed.

关键词： polyethylene pipe nuclear power plant ultrasonic inspection nondestructive testing safety assessment

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Enhancing mixing of particles by baffies in a rotating drum mixer

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Particuology 2011年第3期9卷 270-278页

作者： Maoqiang Jiang Yongzhi Zhao Gesi Liu jinyang zheng State Key Laboratory of Chemical Engineering Institute of Chemical Process Equipment Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027China

Baffles with shape of ＂-＂（single baffle）, ＂＋＂（cross-baffles with four arms） and （baffles with 6 arms） are used to enhance the mixing of particles in a rotating drum mixer. A micro-dynamics study of mixing and segregation ofa bi-disperse system of two particle sizes in the rotating drum with these three kinds of baffles is carried out using the discrete element method （DEM）. The effect of the baffles on mixing, and the mechanisms of mixing enhancement by the baffles are discussed and analyzed. Simulation results show that in an unbaffled drum mixer, particle convection, particle diffusion, and size segregation of hi- disperse particles, all play important roles in the mixing process; whereas size segregation will be largely restrained when the drum mixer has a baffle, regardless of its shape, and the degree of mixing is higher than that in an unbaffled drum mixer. The different mixing characteristics for ＂-＂ shaped baffle, ＂＋＂ baffle, and baffle are revealed by the simulation results. For ＂＋＂ or style baffles, there is an optimal size of baffles for the mixing of particles, and the ootimal mixing efficiency is higher than that for ＂-＂ baffle.

关键词： Particle mixing Size segregation Baffle Drum mixer Discrete element method (DEM)

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Advancements in synthetic and electrocatalytic exploitation of guest-host intercalated 2D materials

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Progress in Natural Science:Materials International 2024年第3期34卷 454-469页

作者： Qian Yang Kun Wang Meiling Zhang Feihong Du Jiayang Li Chen zheng jinyang Li School of Chemistry Southwest Jiaotong University Yibin Institute of Southwest Jiaotong University

The emergence and development of layered materials have shown great promise for many applications, especially in recent years, the effective modulation of the physicochemical properties of layered materials by intercalation chemistry has led to great potential in material design. In this paper, we review the reaction mechanisms of different guest species(metal atoms/ions, organic molecules/ions, inorganic molecules and inorganic ions)intercalated into the host layered materials as well as the recent progress. It is also reviewed that layered intercalated materials with controllable structure and tunable physicochemical properties can be prepared through the occurrence of interactions between different subjects and guests. The specific applications of intercalation chemistry in the field of electrocatalysis, such as the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction and other electrocatalytic reactions, are then discussed, with emphasis on the mechanism of the improved catalytic activity and stability of the layered materials after guest intercalation.

关键词： Electrocatalysis Guest species Intercalation chemistry Layered materials

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肺部感染儿童支气管肺泡灌洗液病原及细胞学分析

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中国当代医药 2024年第1期31卷 64-67页

作者：尤玉婷曾丽娥林春燕陈琼华林洁如郑敬阳福建省泉州市儿童医院呼吸内科福建泉州362000

目的分析肺部感染儿童支气管肺泡灌洗液(BALF)中的病原及细胞学成分,为临床提供诊断及治疗依据方法选取2021年8月至2022年10月于泉州市儿童医院住院治疗的42例患儿作为研究对象,其中23例BALF培养确诊为细菌感染性肺炎的患儿为细菌性肺炎... 详细信息

目的分析肺部感染儿童支气管肺泡灌洗液(BALF)中的病原及细胞学成分,为临床提供诊断及治疗依据方法选取2021年8月至2022年10月于泉州市儿童医院住院治疗的42例患儿作为研究对象,其中23例BALF培养确诊为细菌感染性肺炎的患儿为细菌性肺炎组,19例支气管异物行异物取出术后BALF培养无细菌生长的患儿为支气管异物组。采用液基细胞学沉降法对上述两组患儿BALF进行病理学分析。结果23例细菌性肺炎以肺炎链球菌感染为主,肺部CT易合并肺不张;19例支气管异物以左主支气管异物多见,其中以坚果类异物为主。细菌性肺炎组的中性粒细胞百分比、C反应蛋白(CRP)水平高于支气管异物组,差异有统计学意义(P0.05)。结论儿童细菌性肺炎以肺炎链球菌感染多见,其BALF细胞学组成以中性粒细胞为主,这为临床诊断及治疗提供了依据,避免临床抗生素滥用。

关键词：细菌性肺炎支气管肺泡灌洗液细胞学分析儿童

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Numerical Simulation of the Flat Ribbon Wound Explosion Containment Vessels Subjected to Internal Blast Loading

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Transactions of Tianjin University 2006年第B9期12卷 223-227页

作者： SONG Yanze LI Zhiqiang ZHAO Longmao zheng jinyang Institute of Applied Mechanics Taiyuan University of Technology Taiyuan 030024 China Institute of Chemical Machinery and Equipment Zhejiang University Hangzhou 310037 China

In order to constitute engineering design methods of the flat ribbon wound explosion containment vessels, the dynamic response of such vessels subjected to internal explosion loading is simulated using LS-DYNA3D. Three winding angles, 10°, 15°and 20°, are considered. It is shown that among ribbon vessels investigated, the center displacement of outermost ribbons of the vessel with 10°winding angle is the smallest under the same blast loading. The response of vessels loaded in inner core is local. From the center of the cylindrical shell to the bottom cover, the maximum strain gradually decreases. The ribbons are subjected to tension in the length direction and compression in the width direction. Blasting shock energy concentrates on where is close to center section of blasting. For comparison, numerical simulation of a monobloc thick-walled explosion containment vessel is also investigated. It can be found that the biggest deformation of the flat ribbon wound explosion containment vessels is bigger than that of the monobloc thick-walled explosion containment vessel in the center section of blasting under the same TNT. Numerical results are approximately in agreement with experimental ones. It is proved that the ribbon vessels have the valuable properties of ' leak before burst at worst' compared with the monobloc vessels through numerical simulation.

关键词： flat ribbon wound explosion containment vessels blast loading dynamic response numerical simulation

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纳米磁性颗粒增强酸性矿山废水污泥沉降性能研究

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资源环境与工程 2024年第5期38卷 603-611页

作者：施妍黄应平高敏黄雨淋廖复东郑金阳漆光东陶恩刚龚芳湖北省地质局第七地质大队湖北宜昌443100 宜昌市地质资源与地质工程重点实验室湖北宜昌443100 三峡大学水利与环境学院湖北宜昌443002

针对宜昌市某废弃煤矿山酸性矿山废水(AMD)污泥沉降效率低下的问题,采用溶剂热法成功合成纳米磁性颗粒(MNPs),并系统研究MNPs与阴离子聚丙烯酰胺(APAM)絮凝剂联合作用对AMD污泥沉降性能的增强机制。实验结果表明,在MNPs与APAM最佳用量(... 详细信息

针对宜昌市某废弃煤矿山酸性矿山废水(AMD)污泥沉降效率低下的问题,采用溶剂热法成功合成纳米磁性颗粒(MNPs),并系统研究MNPs与阴离子聚丙烯酰胺(APAM)絮凝剂联合作用对AMD污泥沉降性能的增强机制。实验结果表明,在MNPs与APAM最佳用量(分别为0.2和1 g/L)条件下,APAM显著缩短污泥沉降的时间,沉降速率从1.6 cm/min提升至2.5 cm/min,增幅高达56.3%,有效地提升了处理效率。同时,MNPs的协同作用进一步增强污泥的压缩与脱水能力,临界点体积比(V_(f)/V_(m))_(cp)从0.27降低至0.19,有效地降低了处理成本。通过光学显微镜观察发现,MNPs在絮凝体中的分布可增强颗粒间相互作用,促进高效沉降与体积压缩。MNPs与APAM联合处理后的出水水质显著改善,各项指标均趋近于或达到国家相关排放标准,体现了该技术在环境修复中的有效性。此外,磁絮体再生实验显示,MNPs回收率近90%,且多次循环使用后其沉降效能保持稳定,验证了该技术的经济性与可持续性。

关键词：酸性矿山废水纳米磁性颗粒絮凝污泥沉降

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Sensitive humidity sensor based on moisture-driven energy generation

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Nano Research 2024年第6期17卷 5578-5586页

作者： Qingchao Ni Qing Lou Chenglong Shen Guangsong zheng Runwei Song Jingnan Hao Jialu Liu jinyang Zhu Jinhao Zang Lin Dong Chong-Xin Shan Henan Key Laboratory of Diamond Optoelectronic Materials and Devices Key Laboratory of Materials PhysicsMinistry of Educationand School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China State Centre for International Cooperation on Designer Low-Carbon&Environmental Materials and School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China

The emergence of novel self-powered humidity sensors has attracted considerable attention in the fields of smart electronic devices and personal ***,self-powered humidity sensors have been fabricated using a moisture-driven energy generation(MEG)device based on asymmetric tubular graphitic carbon nitride(g-CN)films prepared on anodized aluminum(AAO)*** a relative humidity(RH)of 96%,the MEG device can provide an open-circuit voltage of 0.47 V and a short-circuit current of 3.51μA,with a maximum output power of 0.08μ*** inherent self-powered ability and humidity response via current variation,an extraordinary response of 1.78×106%(41%-96%RH)can be gained from the MEG *** possible power generation mechanism is that g-CN/AAO heterostructure can form ion gradient and diffusion under the action of moisture to convert chemical potential into electrical potential,evoking a connaturally sensitive response to ***-powered respiration monitoring device based on the sensor is designed to monitor human movement(sitting,warming up,and running)and sleep status(normal,snoring,and apnea),maintaining excellent stability during cumulative 12-h respiration *** self-powered humidity sensing technology has promising potential for extensive integration into smart electronic and round-the-clock health monitoring devices.

关键词： graphitic carbon nitride moisture-driven energy generation humidity sensor respiration monitoring

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内压作用下的航空轮胎爆破碎片动力响应

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航空学报 2017年第8期38卷 134-143页

作者：张帆郑津洋马利浙江大学能源工程学院杭州310012 浙江工业大学应用力学研究所杭州310012

航空轮胎爆破时受内压释放的影响,爆破碎片的速度会有明显增加,而非与适航标准规定的与轮胎降落时的胎速相同。利用Fluent中用户自定义函数编写动力响应程序,采用动网格和用户自定义函数相结合的方法,展开内压释放作用下的轮胎爆破碎片... 详细信息

航空轮胎爆破时受内压释放的影响,爆破碎片的速度会有明显增加,而非与适航标准规定的与轮胎降落时的胎速相同。利用Fluent中用户自定义函数编写动力响应程序,采用动网格和用户自定义函数相结合的方法,展开内压释放作用下的轮胎爆破碎片速度动力响应特性的数值模拟研究。假设轮胎爆破失效是存在先前缺陷造成的,将碎片受冲击后的动态过程分解为内压释放冲击加速阶段和以一定初速度在空气阻力下减速运动两个阶段,提出仅考虑碎片两侧实时压力差作为动力源的简化物理爆破模型,来分析碎片的速度受内压作用的响应和整个流场压力以及速度变化情况,弥补了数学模型未考虑内外压平衡过程的不足,为预测轮胎爆破后碎片获得能量和爆破气流能量等提供数值参考,以便提出相应的安全防范措施。

关键词：航空轮胎爆破碎片流固耦合 CFD 用户自定义函数

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世界视野与时俱进——中国音乐史学会第七届年会综述

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音乐研究 2002年第3期 94-95页

作者：郑锦扬福建师范大学

21世纪的首次中国音乐史学会年会于2002年7月27日至30日在福州举行."双福杯"第三届全国高校学生中国音乐史论文评选的颁奖仪式,亦在7月27日年会开幕式上隆重举行.

关键词：中国音乐史学开幕式颁奖仪式福州史论视野

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我国承压设备学的研究现状和优先研究领域

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石油机械 2005年第3期33卷 21-24页

作者：郑津洋浙江大学化工机械研究所

在阐述承压设备的最新发展趋势后, 分析了我国承压设备学研究现状及与国外先进水平的差距。提出今后我国承压设备学基础研究优先研究的领域: (1) 承压设备结构与传热、传质和反应效率的关系; (2) 复杂环境下承压设备的力学行为和破... 详细信息

在阐述承压设备的最新发展趋势后, 分析了我国承压设备学研究现状及与国外先进水平的差距。提出今后我国承压设备学基础研究优先研究的领域: (1) 承压设备结构与传热、传质和反应效率的关系; (2) 复杂环境下承压设备的力学行为和破坏特性; (3) 承压设备的全寿命数字化设计; (4) 承压设备断裂、腐蚀与冲蚀的特性和机制; (5) 承压设备监控预警和应急系统;(6) 承压设备法规标准基础研究。

关键词：优先中国最新发展设备预警趋势机制承压传质反应效率

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