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A Design of Modular Interior Ferrite Magnet Fluxswitching Linear Motor for Track Transport

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CES Transactions on Electrical Machines and Systems 2024年第3期8卷 284-294页

作者： zongsheng zhang Hao Wang Hong Chen College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

A novel topology of modular ferrite magnet fluxswitching linear motor(FMFSLM)use for track transport is presented in this paper,which enables more ferrite magnets to be inserted into the primary iron *** motor has a significant low-cost advantage in long-distance linear *** proposed FMFSLM’s structure and working principle were ***,the thrust force expression of the motor was *** thrust force components triggering thrust force ripple were investigated,and their expressions can be obtained according to the inductances’Fourier series ***,the relationship between the harmonics of thrust force and that of self-and mutual inductances was revealed *** on the relationship,a skewed secondary should be practical to reduce the thrust force ***,the effect of employing a skewed secondary to the proposed FMFSLM was investigated,and an optimized skewing span distance was *** element analysis(FEA)was conducted to validate the exactness of the theoretical *** simulation results indicate that the strategy of suppressing thrust force ripple has a significant ***,the motor maintains a good efficiency *** results of the prototype experiment are in good agreement with FEAs,which further verifies the proposed modular interior FMFSLM’s practicability.

关键词： Ferrite magnet flux-switching linear motor(FMFSLM) Detent force Resistance force Force ripple Skewed secondary

Enhanced stability of FA-based perovskite:Rare-earth metal compound EuBr_(2) doping

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Chinese Physics B 2024年第4期33卷 669-675页

作者：候敏娜郭旭韩梅斗雪赵均陶王志元丁毅侯国付张宗胜韩小平 School of Energy and Power Engineering North University of ChinaTaiyuan 030051China Institute of Photoelectronic Thin Film Devices and Technology Nankai UniversityTianjin 300072China

It is highly desirable to enhance the long-term stability of perovskite solar cells(PSCs)so that this class of photovoltaic cells can be effectively used for the commercialization *** this contribution,attempts have been made to use the two-step sequential method to dope EuBr_(2)into FAMAPbI_(3)perovskite to promote the *** is shown that the device durability at 85℃in air with RH of 20%-40%is improved substantially,and simultaneously the champion device efficiency of 23.04%is *** enhancement in stability is attributed to two points:(ⅰ)EuBr_(2)doping effectively inhibits the decomposition andα-δphase transition of perovskite under ambient environment,and(ⅱ)EuBr_(2)aggregates in the oxidized format of Eu(BrO_(3))_(3)at perovskite grain boundaries and surface,hampering humidity erosion and mitigates degradation through coordination with H_(2)O.

关键词： EuBr_(2) doping inhibited phase transition and decomposition stability perovskite solar cell

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复杂地层中深大基坑开挖变形特征和优化设计

建筑结构 2024年第13期54卷 141-148页

作者：潘有旺王楠张宗盛程远江甘肃省建筑科学研究院(集团)有限公司兰州730070 兰州交通大学土木工程学院兰州730070

复杂地层中的基坑开挖对周边环境会产生很大的干扰和影响。以兰州市兰石14#地块建设项目基坑为工程背景,运用有限元软件MIDAS进行基坑开挖数值模拟,同时结合现场监测数据进行研究分析。结果表明:在基坑开挖过程中桩身水平位移最大为13.5... 详细信息

复杂地层中的基坑开挖对周边环境会产生很大的干扰和影响。以兰州市兰石14#地块建设项目基坑为工程背景,运用有限元软件MIDAS进行基坑开挖数值模拟,同时结合现场监测数据进行研究分析。结果表明:在基坑开挖过程中桩身水平位移最大为13.5mm,基坑周边竖向位移最大为12.1mm,桩身及锚索受力与基坑开挖深度呈正比关系且满足规范要求。同时针对原有基坑设计方案进行了优化分析,对比了不同放坡坡率和不同桩径等影响因素。结果显示:当采取600mm桩径、桩间距为1.2m的支护桩,放坡坡率为1∶0.5时,基坑变形与原设计基本一致,优化后的开挖支护方案可有效降低基坑的开挖支护成本。

关键词：复杂地层深大基坑数值模拟基坑变形优化设计

Impacts of Climate and Nutrients on Carbon Sequestration Rate by Wetlands: A Meta-analysis

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Chinese Geographical Science 2020年第3期30卷 483-492页

作者： CHENG Caifeng LI Min XUE Zhenshan zhang zongsheng LYU Xianguo JIANG Ming zhang Hongri College of Geomatics Shandong University of Science and TechnologyQingdao 266590China Northeast Institute of Geography and Agroecology Chinese Academy of ScienceChangchun 130024China

Global numerous wetlands are the most productive ecosystem and have high carbon sequestration potential to mitigate increasing CO2 in the atmosphere. However, few are available on estimating average carbon sequestration rates by global wetlands(Carbonsq) at century timescale. In this article, Carbonsq data of 473 wetland soil/sediment cores from the literatures were collected in detail by the meta-analysis method. These cores were no more than 300 years old and spanned a latitudinal range from 33.6° S to 69.7° N. Globally, the average Carbonsq was 185.2 g/(m^2·yr) regardless of wetland types. Carbonsq varied remarkably between wetland types and ranked as an order of salt marsh(247.7 g/(m^2·yr)) > mangrove(229.8 g/(m^2·yr)) > freshwater marsh(196.7 g/(m^2·yr)) > peatland(76.9 g/(m^2·yr)). Carbonsq was positively related to mean annual temperature(AMT) and annual precipitation(Pre). Nitrogen was the most common and primary factor controlling Carbonsq regardless of wetland types.

关键词： global wetlands carbon sequestration temperature and precipitation nutrient phosphorus

内镜下注水法冷圈套器切除术在治疗5~10 mm无蒂型大肠息肉中的疗效分析

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广州医药 2024年第3期55卷 300-305,310页

作者：张宗胜陈明仁刘浪廷李卫娜韩燕燕卢敏阳春市中医院消化内科广东阳春529600 南方医科大学珠江医院消化内科广东广州510280

目的研究注水法内镜下冷圈套器切除术在5~10 mm无蒂型大肠息肉中的临床疗效。方法纳入120例阳春市中医院收治的5~10 mm无蒂型大肠息肉患者,合计246枚息肉,根据结肠息肉切除方式不同分为内镜下注水法冷圈套器切除术(UCSP)与传统内镜下冷... 详细信息

目的研究注水法内镜下冷圈套器切除术在5~10 mm无蒂型大肠息肉中的临床疗效。方法纳入120例阳春市中医院收治的5~10 mm无蒂型大肠息肉患者,合计246枚息肉,根据结肠息肉切除方式不同分为内镜下注水法冷圈套器切除术(UCSP)与传统内镜下冷圈套器切除术(CCSP)两组,每组分别纳入60例患者。比较两组息肉部位、息肉大小、术后病理诊断、完整息肉切除率、术后病理深度、息肉回收率、手术时间、术中瞬时性出血率、迟发性穿孔率、迟发性出血率以及手术时间、Boston及视觉模拟评分法(VAS)评分。结果两组息肉部位、息肉大小、术后病理诊断、完整息肉切除率、息肉回收率、术中瞬时性出血率、迟发性穿孔率、迟发性出血率以及Boston评分比较差异均无统计学意义(P>0.05);UCSP组术后病理深度[(8.80.5)mm]大于CCSP组[(5.90.4)mm](P<0.01),CCSP组手术时间[(21.32.4)min],较UCSP组[(25.71.1)min]缩短(P<0.01),VAS评分UCSP组[(2.60.7)分]优于CCSP组[(2.90.3)分](P<0.001)。结论UCSP能有效、安全5~10 mm无蒂型大肠息肉,术后深度的病理组织学评估获得更高的肌层黏膜切除深度,虽然UCSP手术时间较长,但术后腹痛发生率较低。

关键词：注水冷圈套器切除术冷圈套息肉切除术大肠息肉瞬时性出血腹痛

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佛山黄岐海北片区岩溶地面塌陷地质灾害成因与趋势分析

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中国岩溶 2022年第6期41卷 880-894页

作者：张宗胜广东省佛山地质局广东佛山528000

佛山市南海区大沥镇黄岐海北片区地处珠江三角洲北部广花盆地边缘地带,第四纪软土、砂土以及隐伏岩溶发育,早期因区内人类工程活动强烈,诱发了群发性岩溶地面塌陷。文章在分析地质环境概况的基础上,研究了区内岩溶地面塌陷的发育特征和... 详细信息

佛山市南海区大沥镇黄岐海北片区地处珠江三角洲北部广花盆地边缘地带,第四纪软土、砂土以及隐伏岩溶发育,早期因区内人类工程活动强烈,诱发了群发性岩溶地面塌陷。文章在分析地质环境概况的基础上,研究了区内岩溶地面塌陷的发育特征和成因机理,认为溶洞土洞发育是先决条件,导水断裂发育是必要条件,因施工引发的地下水位下降是主要触发因素,F1断裂带附近仍具备发生岩溶塌陷的可能性,控制地下水水位标高在-3.0 m以内,地下水水位波动范围在1.5 m以内,可以大幅度降低岩溶塌陷发生概率,可以以此作为预警报警阈值。研究结果可以为佛山市城镇化建设过程中岩溶地面塌陷防治提供依据,也可以为其他类似地区防灾减灾提供借鉴。

关键词：岩溶地面塌陷成因机制趋势分析施工降水导水断裂佛山市

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颅底动脉瘤样骨囊肿1例并文献复习

临床神经外科杂志 2024年第4期21卷 469-471,476页

作者：秦振伟陈丁唐北燕张宗盛代军强董强康暐赵贤军段磊潘亚文兰州大学第二医院神经外科兰州730000 甘肃省康复中心医院医务科兰州新区第一人民医院重症医学科

目的总结颅底动脉瘤样骨囊肿(ABC)的临床特征并复习颅底特殊部位病变相关手术技巧。方法回顾性分析兰州大学第二医院2021年12月收治的1例颅底ABC患者的临床资料,并结合相关文献对颅底ABC及相关手术技巧进行复习。结果行额颞开颅硬膜... 详细信息

目的总结颅底动脉瘤样骨囊肿(ABC)的临床特征并复习颅底特殊部位病变相关手术技巧。方法回顾性分析兰州大学第二医院2021年12月收治的1例颅底ABC患者的临床资料,并结合相关文献对颅底ABC及相关手术技巧进行复习。结果行额颞开颅硬膜外入路全切肿瘤,术后病理诊断为ABC。随访期间未见肿瘤复发。结论 ABC位于颅底的发病部位少见,诊断难度较高,首选治疗方案为手术完整切除。

关键词：颅底动脉瘤样骨囊肿额颞开颅硬膜外入路

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Outage Performance of Cognitive Relay Networks with Best Relay Selection in Nakagami-m Channels

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Communications and Network 2013年第3期5卷 166-170页

作者： zongsheng zhang Qihui Wu Jinlong Wang Xueqiang Zheng Xinhong Shao Cheng Tan Affiliation: College of Communications Engineering PLA University of Science and Technology No. 2 YuDao Street Nanjing China

This paper investigates the outage performance of a cognitive relay network considering best relay selection in Nakagami-m fading environment. The secondary user is allowed to use the spectrum when it meets the interference constraints predefined by primary user. Due to deep fading, cognitive source is unable to communicate directly with cognitive destination. As such, multiple relays are ready to deliver the signal from the cognitive source to cognitive destination. We select a single best relay and the selected relay uses decode-and-forward protocol. Specifically, we derive the exact outage probability expression, which provides an efficient means to evaluate the effects of several parameters. Finally, numerical simulation results are presented, which validate the correctness of the analytical analysis.

关键词： Cognitive Realy Networks (CRNs) Nakagami-m Fading Outage Probability

消除单相磁通切换型磁阻电机启动死区的新型转子结构及其实验研究

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中国电机工程学报 2015年第18期35卷 4779-4789页

作者：张宗盛王秀和杨玉波山东大学电气工程学院山东省济南市250061

该文提出一种新型转子设计方案,以克服单相磁通切换型磁阻电机(flux switching motor,FSM)存在启动死区的不足。文章分析了单相FSM的工作特点及现有关于改善、消除启动死区方法的特点与不足,基于此提出一种"错位"装配的转子设计方案,并... 详细信息

该文提出一种新型转子设计方案,以克服单相磁通切换型磁阻电机(flux switching motor,FSM)存在启动死区的不足。文章分析了单相FSM的工作特点及现有关于改善、消除启动死区方法的特点与不足,基于此提出一种"错位"装配的转子设计方案,并对两种具体的"错位"装配转子结构进行了3D有限元仿真分析,最终选取了由两种不同极弧长度叠片组成的转子结构。阐述了装有该新型转子FSM控制电路的选取原则及控制方法的特点,搭建了整个电机系统的联合仿真模型并进行仿真,制作了装有新型转子的FSM样机及控制器并进行了实验测试。仿真分析与实验测试结果表明,该文所设计的新型转子结构实现了消除单相FSM启动死区的研究目标,具有很好的实用价值。

关键词：单相磁通切换型磁阻电机启动死区错位装配 3D有限元仿真实验研究