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剖分式机械密封分析研究

矿山机械 2015年第2期43卷 5-8页

作者：冯斐斐杨启明毛东壁罗谨灵西南石油大学机电工程学院四川成都610500

剖分式机械密封是一种拆装方便、速度快及维修更换时间短的密封结构,但由于这种密封存在耐受压力不高的缺点,至今未得到广泛推广应用,也未见深入开展相关理论分析与实验研究。通过对国内外的研究现状进行回顾与总结,从密封环变形、分型... 详细信息

剖分式机械密封是一种拆装方便、速度快及维修更换时间短的密封结构,但由于这种密封存在耐受压力不高的缺点,至今未得到广泛推广应用,也未见深入开展相关理论分析与实验研究。通过对国内外的研究现状进行回顾与总结,从密封环变形、分型面连接紧密性、摩擦面变形、端面改型及泄漏率等方面提出了理论研究的发展方向,并指出现代设计方法以及新材料、新技术的应用,将给剖分式机械密封的研究带来新的应用前景。

关键词：剖分式机械密封分型面

心理护理在神经外科ICU气管切开患者中的应用

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临床医学工程 2017年第1期24卷 121-122页

作者：罗进玲李云玲叶秋容陈家欢广东省肇庆市第一人民院神经外科ICU 广东肇庆526020

目的探讨心理护理应用于神经外科ICU气管切开患者中的价值。方法选取我院神经外科ICU收治的行气管切开患者127例,随机分为观察组(63例)和对照组(64例)。对照组给予常规护理干预,观察组在此基础上给予心理护理。对比分析两组患者的GCS评... 详细信息

目的探讨心理护理应用于神经外科ICU气管切开患者中的价值。方法选取我院神经外科ICU收治的行气管切开患者127例,随机分为观察组(63例)和对照组(64例)。对照组给予常规护理干预,观察组在此基础上给予心理护理。对比分析两组患者的GCS评分、SAS评分和SDS评分。结果护理后,观察组患者的GCS评分明显高于对照组,SAS评分和SDS评分均明显低于对照组,差异均具有统计学意义(P均<0.05)。结论在神经外科ICU气管切开患者临床护理中应用心理护理,有助于改善患者的心理状态,促进各项治疗与护理措施的落实和患者神经功能的恢复。

关键词：心理护理 ICU 气管切开

Deformation and failure behavior of heterogeneous Mg/SiC nanocomposite under compression

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Journal of Magnesium and Alloys 2022年第12期10卷 3433-3446页

作者： Xi luo jinling Liu Leigang Zhang Xu He Ke Zhao Linan An State Key Laboratory of Traction Power&School of Mechanics and Engineering Southwest Jiaotong UniversityChengduSichuan610031China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province Southwest Jiaotong UniversityChengduSichuan610031China Department of Materials Science and Engineering University of Central FloridaOrlandoFL32816United States

The heterogeneous magnesium(Mg) matrix nanocomposite with dispersed soft phase exhibits high strength and toughness. Herein, the deformation behavior and failure process were investigated to reveal the unique mechanical behavior of the heterogeneous microstructure under compression. The extensive plastic deformation is accompanied by the flattening and tilting of the soft phase, inhibiting strain localization and leading to strain hardening. Moreover, a stable crack multiplication process is activated, which endows high damage tolerance to the heterogeneous Mg matrix nanocomposites. The final failure of the composite is caused by crack coalescence in the shear plane along a tortuous path. The presence of dispersed soft phases within the hard matrix induces a noticeable change in mechanical response. Especially,the malleability of the heterogeneous Mg matrix nanocomposite is two and ten times higher than that of pure Mg and the homogeneous Mg matrix nanocomposite, respectively. The current study provides a novel strategy to break the trade-off between strength and toughness in metal matrix nanocomposites.

关键词： Magnesium matrix nanocomposites Heterogeneous structure Malleability Microstructural evolution

Erosion Behavior of NiCoCrFeNb_(0.45) Eutectic High-Entropy Alloy in Liquid-Solid Two-Phase Flow

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Acta Metallurgica Sinica(English Letters) 2022年第8期35卷 1266-1274页

作者： Kai Wang Zhenjiang Wang jinling Lu Zhijun Wang Wei Wang Xingqi luo State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xi'an University of TechnologyXi'an 710048China State Key Laboratory of Solidification Procesing Northwestern Polytechnical UniversityXi'an 710072China

The metal components exposed to the high-velocity liquid-solid flow can be rapidly eroded by the accelerated *** an excellent combination of strength and toughness,the NiCoCrFeNb_(0.45)eutectic high-entropy alloy(EHEA)has emerged as a promising material to resist erosion *** this study,the erosion behavior of NiCoCrFeNb_(0.45)EHEA in high-velocity multiphase flow is investigated through the coupling analysis of material properties,multiphase flow,and particle–surface impact *** inherent mathematical relationship is discovered between the erosion rates and the impact velocity,impact angle,and test *** results show that the NiCoCrFeNb_(0.45)EHEA has superior erosion resistance than the commonly used machinery *** principal material removal mechanism is the formation and brittle fracture of the platelets,accompanied by micro-cutting and ploughing at some oblique *** higher work-hardenability of NiCoCrFeNb_(0.45)EHEA could mitigate the erosion damage as time proceeds,and this effect becomes more apparent as the impact angle ***,the evolution of erosion damage with time varies significantly depending on the impact *** on the test data and computational fluid dynamics(CFD)modeling of the near-wall flow field,a power exponential function relationship between erosion depth and the corresponding impact velocity at various locations on the material surface is established.

关键词： Eutectic high-entropy alloy Erosion evolution Multiphase flow Computational fluid dynamics(CFD)modeling

Multi-physics analysis of the galvanic corrosion of Mg-steel couple under the influence of time-dependent anisotropic deposition film

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Journal of Magnesium and Alloys 2021年第3期9卷 866-882页

作者： Kai Wang Chenpei Li Yanhui Li jinling Lu Yueshe Wang Xingqi luo State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi'an University of TechnologyNo.5 Jinhua South RoadXi'an 710048China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityNo.28 Xianning West RoadXi'an 710049China

The anisotropic deposit film formed during the galvanic corrosion can impede the mass transfer of the involved species,thereby affecting the electro-chemical behavior and the evolution of galvanic *** limitations of experimental studies in the spatial-temporal scales restrict a deeper understanding of the corrosion mechanism,which can be complemented by numerical simulation.A multi-physics coupled model is proposed in this work to systematically investigate the temporal and spatial evolution of galvanic corrosion of the Mg-steel couple with the growing anisotropic deposition *** utilizing the multi-physics field coupled technique,various coupled physical-chemical processes underlying the corrosion behavior are built into the model,including chemical reactions,ionic mass transfer in the bulk solution and the deposition layer,interfacial reaction,deposition of corrosion products as well as the morphological transitions caused by metal dissolution and *** particular,the anisotropic deposit film is considered to be a porous layer with a porosity varying in time and space as the corrosion *** predicted corrosion morphology by this model is better than the previous *** coupled relationship between the electrochemical behavior(e.g.,electrode reaction kinetics,current density,surface potential)and the physical processes(e.g.,ionic transport,geometric evolution of metal surface and film interface)is *** results indicate that a porous deposition layer with a denser inner layer and a loose outer layer is generated,leading to more significant inhibition of mass transfer in the inner layer than the outer *** anisotropism of the deposition layer results in a non-uniform conductivity distribution and a discontinuous current density distribution in the *** current density on the electrode surface is inhibited by the deposition layer and the variation in the cathode/anode area ratio during the corrosion *** c

关键词： Galvanic corrosion Corrosion product film Modeling Mass transport Porosity

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龙山县马铃薯绿色高效栽培技术推广与应用

农业技术与装备 2023年第5期 71-72页

作者：向烨向莉兰付文晶罗金玲刘红梅龙山县农业技术推广中心湖南龙山416800

龙山县推广马铃薯绿色高效栽培技术,实现了改良土壤结构、优化耕作环境、降低病虫危害,减少农药施用、促进生态平衡的目标,为提高马铃薯种植水平、加速农业科技转化、乡村振兴提供技术支撑。

关键词：龙山县马铃薯绿色高效栽培技术

维普期刊数据库博看期刊

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氟对斑马鱼胚胎/仔鱼的神经毒性效应研究

环境科学学报 2024年第3期44卷 459-467页

作者：许梦燕芦钰婷孙毅牛旭凯韩笑月罗永巨陈剑杰曹谨玲山西农业大学食品科学与工程学院太谷030801 山西农业大学动物医学学院太谷030801 晋中市农业农村局榆次030600 广西水产科学研究院南宁530021

为研究氟对斑马鱼胚胎/仔鱼的神经毒性效应,将2 hpf(受精后2 h)斑马鱼胚胎暴露于0、20、40和80 mg·L^(-1)的氟化钠溶液中,观察并分析氟暴露对斑马鱼胚胎/仔鱼的胚胎发育和行为学的影响,采用组织学方法对斑马鱼脑组织病理情况进行观察,... 详细信息

为研究氟对斑马鱼胚胎/仔鱼的神经毒性效应,将2 hpf(受精后2 h)斑马鱼胚胎暴露于0、20、40和80 mg·L^(-1)的氟化钠溶液中,观察并分析氟暴露对斑马鱼胚胎/仔鱼的胚胎发育和行为学的影响,采用组织学方法对斑马鱼脑组织病理情况进行观察,测定其超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽(GSH)抗氧化参数,利用酶联免疫吸附法检测多巴胺含量,实时荧光定量PCR方法检测多巴胺相关基因的表达.结果显示,与对照组比较,氟暴露可以导致斑马鱼胚胎/仔鱼出现卵黄囊水肿、脊柱弯曲等异常现象;氟暴露各组48 hpf斑马鱼心率明显升高,72 hpf斑马鱼机械逃避反射次数明显下降,120 hpf斑马鱼光暗反应过程中平均速度降低,氟暴露40、80 mg·L^(-1)组24 hpf斑马鱼摆尾次数明显增加,72 hpf斑马鱼孵化率明显降低,120 hpf斑马鱼死亡率显著增加;脑组织病变程度随着氟暴露浓度的增大而加重;相较对照组,氟暴露各组GSH含量均显著下降,MDA含量均显著升高,SOD活性在40、80 mg·L^(-1)组下降明显,多巴胺含量在80 mg·L^(-1)组下降明显;氟暴露各组dat、zc4h2、drd1、drd2a、drd2b、drd3、drd4b基因表达水平都明显下降.由此可见,氟暴露对斑马鱼胚胎/仔鱼具有明显的神经毒性作用,本研究结果对进一步探究氟的毒性效应及健康风险性评价提供了理论支持.

关键词：氟化钠斑马鱼多巴胺神经毒性

连续性肾脏替代治疗联合换血治疗重症百日咳患儿1例护理

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上海护理 2021年第7期21卷 74-76页

作者：邝慧仪春晓钟咏梅罗金玲杨翠萍广州市妇女儿童医疗中心广东广州510623

百日咳是由百日咳杆菌引起的严重急性呼吸道传染病,病情重、并发症多。儿童,特别是未完成免疫接种的低龄儿是百日咳的易感人群[1]。据WHO数据显示,2019年全球约132754例患者感染百日咳,2008年估算病死约89000例[2]。多项国外多中心研究[... 详细信息

百日咳是由百日咳杆菌引起的严重急性呼吸道传染病,病情重、并发症多。儿童,特别是未完成免疫接种的低龄儿是百日咳的易感人群[1]。据WHO数据显示,2019年全球约132754例患者感染百日咳,2008年估算病死约89000例[2]。多项国外多中心研究[3-4]结果均提示,高白细胞血症为重症百日咳患儿死亡的重要危险因素。国内儿童百日咳诊断建议[5]中指出,对于0~3月龄的婴儿,当白细胞(white blood cell,WBC)计数≥20×10^(9)/L时即提示高白细胞血症。

关键词：百日咳,高白细胞血症,重症连续性肾替代治疗(CRRT) 联合换血术,护理

Molecular cloning and expression analysis of FTZ-F1 in the GIFT tilapia,Oreochromis niloticus

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Zoological Research 2012年第S2期33卷 I0012-I0018页

作者： jinling CAO Jianjie CHEN Zhongliang JIANG Yongju luo Xi GAN State Key Laboratory of Ecological Animal Husbandry and Environmental Veternary Medicine Shanxi Agricultural University030801 TaiguShanxiChina Guangxi University 530021 NanningChina Guangxi Fisheries Research Institute 530021 NanningChina

The FTZ-F1 genes encode orphan receptors of the nuclear receptor superfamily and in mammals have been found to play important roles in the proper development of the adrenal-gonadal axis and *** isolated the homologue of FTZ-F1 in genetically improved farmed tilapia(gfFTZ-F1).The full-length cDNA was isolated from the ovary,which included an open reading frame encoding a predicted protein of 486 amino ***,tissue distribution and phylogenic analysis of the FTZ-F1 showed that the gfFTZ-F1 belonged to SF-1/Ad4BP group and that gfFTZ-F1 transcripts were only expressed in the gonads and kidney but not in other *** our data suggests that the gfFTZ-F1 gene may share similar functions with other fish and mammalian counterparts,though further study is needed to make any definitive conclusions.

关键词： GIFT tilapia FTZ-F 1 Cloning Expression