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Oxidation Behavior of K4750 Alloy at Temperatures Between 750°C and 1000°C

Acta Metallurgica Sinica(English Letters) 2021年第12期34卷 1657-1668页

作者： Yan-Li Liu Kun-Lei Hou Mei-qiong ou Ying-Che Ma Kui Liu School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

This study investigated the oxidation behavior of a new casting Ni-based superalloy K4750 at 750°C-1000°C in air for 100 h-1000 h by isothermal oxidation *** oxidation-kinetic curves were plotted by the static discontinuous weight gain *** and identification of oxidation products were conducted using scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),electron probe micro-analysis(EPMA)and X-ray diffraction(XRD).X-ray photoelectron spectrometer(XPS)was also used to analyze the chemical state of elements and the distribution in *** results showed that the oxidation-kinetic curves of K4750 alloy basically obeyed the parabolic *** average oxidation rate below 900°C was less than 0.1 g/m 2·h which meant the alloy was at a complete anti-oxidation grade,and the alloy was at an anti-oxidation grade at 1000°*** predominant surface oxide was Cr_(2)O_(3),and a double layer structure of the oxide scale was observed at all tested temperatures as time *** outer oxide layer contained continuous Cr_(2)O_(3)and a small amount of oxides mixed TiO2 and NiCr2O4,while the inner oxide layer was composed with Al_(2)O_(3).The oxidation process could be interpreted by the competitive oxidation of different *** diffusion rate of Ti through Cr_(2)O_(3)layer increased with increasing temperature,and thus the generation of TiO2 was *** dispersed TiO2 reaching a certain amount destroyed the continuity of the surface oxide layer,which accounted for the reduction of oxidation resistance of K4750 alloy at high temperatures.

关键词： Ni-based superalloy Oxidation Titanium Internal oxides

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Effect of Co on Microstructure and Stress Rupture Properties of K4750 Alloy

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1501-1510页

作者： Xiao-Xiao Li Mei-qiong ou Min Wang Xian-Chao Hao Ying-Che Ma Kui Liu Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

The effects of substituting Co for Fe on the microstructure and stress rupture properties of K4750 alloy were *** microstructure of the alloy without Co(K4750 alloy)and the alloy containing Co(K4750-Co alloy)were *** of Co for Fe inhibited the decomposition of MC carbide and the precipitation ofηphase during long-term aging *** K4750-Co alloy,the morphology of MC carbide at the grain boundary(GB)remained dispersed blocky shape and noηphase was observed after aging at 750℃ for 3000 ***,in K4750 alloy,almost all the MC carbides at GBs broke down into granular M23C6 carbide and needle-likeη*** addition of cobalt could delay the decomposition of MC carbides,which accordingly restricted the elemental supply for the formation ofη*** stress rupture tests were conducted on two alloys at 750℃/430 *** Co is substituted for Fe in K4750 alloy,the stress rupture life increased from 164.10 to 264.67 h after standard heat *** was mainly attributed to increased concentration of Al,Ti and Nb inγ’phase in K4750-Co alloy,which further enhanced the strengthening effect ofγ’*** aging at 750℃ for 3000 h,substitution of Co for Fe can also cause the stress rupture life at 750℃/430 MPa to increase from 48.72 to 208.18 *** reason was mainly because MC carbide degradation andηphase precipitation in K4750 alloy,which promoted the initiation and propagation of micro-crack during stress rupture testing.

关键词： Nickel-based superalloy Co addition MC degradation Stress rupture property

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Association between residential greenness and obstructive sleep apnoea among adults in Southern China

Association between residential greenness and obstructive sl...

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中国睡眠研究会第十五届全国学术年会

作者： Suhan Wang qiong ou Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences) Southern Medical Uni-versity

Background: No previous study has explored the association of residential greenness with obstructive sleep apnoea(OSA) ***: To investigate the association of exposure to residential greenness with OSA indexes in adults in Guangdong Province, Southern ***: From January 1, 2005 to December 31, 2015, a total of 3,925 participants were recruited from the Sleep Center of Guangdong Provincial People's ***-hypopnea index(AHI) and oxygen desaturation index(ODI) were measured by polysomnography or home sleep test(HST).Participants' daytime sleepiness scores were evaluated using The Epworth Sleeping Scale(ESS).The normalized difference vegetation index(NDVI) and enhanced vegetation index(EVI) were used to assess residential greenness *** linear regression models were used to assess the associations of residential greenness with OSA indexes after adjusting for multiple ***: The mean(standard deviation) age of the participants was 63.3(14.4) *** adjusted models, an interquartile range(IQR) increase in 3-year average NDVI was significantly associated with 9.8%(95% confidence interval [95% CI]: 17.5%, 2.1%);14.5%(95% CI: 24.5%, 4.4%) and 6.9%(95% CI: 13.7%, 0.0%) decreases in AHI, ODI and ESS scores, ***, an IQR increase in 3-year average EVI was significantly associated with 7.8%(95% CI: 13.7%, 1.9%);10.8%(95% CI: 18.3%, 3.2%) and 7.2%(95% CI: 12.5%, 2.0%) declines in AHI, ODI and ESS scores, *** were only observed among males, adults aged ≥65 years old, and in the warm ***: our study indicates that higher residential greenness was significantly associated with lower OSA indexes in adult population in South China, especially in males, in the elderly, and in the warm season.

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A Survey of the Current Situation of Obstructive Sleep Apnea Related Hypertension In Healthy incumbent population

A Survey of the Current Situation of Obstructive Sleep Apnea...

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中国睡眠研究会第十届全国学术年会

作者： Minxia Pan qiong ou Baixin Chen Zuogeng Hong Guangdong General Hospital Guangdong Academy of Medical Sciences

Purpose To estimate the prevalence of Obstructive Sleep Apnea（ OSA） related hypertension among healthy incumbent occupations and evaluate the risk of developing OSA related hypertension in this *** A cross-sectional analysis of incumbents from the same unit in Guangzhou was performed,a total of 1241 subjects were administered a standardized sleep-related questionnaire,hypertension assessment and physical *** with positive Berlin questionnaire will accept type III portable sleep monitor for OSA *** is diagnosed according to the 2010 edition of China’s guidelines for the prevention and treatment of *** examination included height,weight,Mallampati classification of oropharynx cavity,*** Group extraction of 1241 incumbents,1036 were obtained complete information finally.22.01%（228/1036） people were positive for the sleep apnea screening *** have already been diagnosed with OSA,73 refused to check,153 completed the diagnosis of OSA,101 accords with the OSA *** prevalence of OSA was 9.94%（103/1036）.48.54（50/103） people meet the diagnostic criteria for OSA and hypertension,30%（15/50） were diagnosed for the first time in this survey,44%（22/50） did not take antihypertensive *** regression analysis showed that BMI,Apnea Hypopnea Index（AHI） and age were significantly correlated with OSA related hypertension（P ＜ 0.05）.Conclusion Among the healthy incumbent occupations population,OSA has a high prevalence rate,48.54% with ***,the proportion of the first diagnosis was large,and most of the patients with OSA related hypertension were undiagnosed and untreated.

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Is CPAP pressure titration always necessary?

Is CPAP pressure titration always necessary?

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中国睡眠研究会第十五届全国学术年会

作者： Qishan Wei Yuanming Luo qiong ou Shanfeng Liang Cuizhen Huang State Key Laboratory of Respiratory Disease The first affiliated hospital of Guangzhou Medical University Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences) Southern Medical University

Background: Patients with OSA are usually treated by automatic CPAP or Fixed CPAP after pressure ***, we have previously shown that auto-titrated CPAP was usually 2-5 cmH2O higher than the manual titrated pressure, suggesting patients whose auto titrated CPAP higher or lower than 10 cmH2O could still be treated by a fixed CPAP at 10 ***: Twenty-one severe OSA patients(age 44.4±11.2 years, BMI 30.3±5.2 kg/m2, AHI 74.8±13.8 events/h) whose 90% of automatic pressure >10 cmH20(mean titrated pressure 13.1±1.9 cmH20) were invited to have an overnight full polysomnography under the fixed CPAP level of 10 ***: The residual AHI in two subjects whose AHI before treatment was 67 events/h and 86 events/h was still unnormal and was 14 events/h and 20 events/h ***, the residual AHI in all other subjects under fixed CPAP at 10 cmH2O was lower than 5 events/*** were no significant differences in AHI between Auto-CPAP and fixed CPAP at 10cmH20( 4.3±1.8 events/h vs 3.2±3.3 events/h;p>0.05).The number of patients who preferred to be treated by Auto-CPAP was similar to by fixed CPAP at 10cmH2O(χ2 = 1.322, P>0.05).Conclusion: A fixed CPAP at 10 cmH2O can be used to treat most severe patients even whose auto titrated pressure is higher than 10 cmH2O.

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The appraisal of excessive daytime sleepiness in the elderly with obstructive sleep apnea/hypopnea syndrome

The appraisal of excessive daytime sleepiness in the elderly...

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The4thASRSCongress

作者： ZHENG Qinwei ou qiong Guangdong Provincial People’s Hospital Guangzhou 510080 China

＜正＞Objectives To explore the condition of excessive daytime sleepiness （EDS） in aged patients with obstructive sleep apnea/hypopnea syndrome （OSAHS） and its characteristic. Methods: Compared with the case of daytime sleepiness between 82 cases in aged group with OSAHS and 90 cases in non-aged group with OSAHS, Epworth Sleep Scales （ESS） was used to test and analyse for their degree of daytime sleepiness. Results The score of ESS in aged patients with OSAHS was less than in non-aged patients （P＜0.05）. And the degree of daytime sleepiness among small, medial, heavy scale condition in aged patients with OSAHS was not significant （P＞0.05）, but it was significant in non-aged patients （P＜0.05）. On the other hand, the incidence of EDS between group were identical （P＞0.05）. Conclusions: The expression of EDS in aged patients with OSAHS had not more obvious than in non-aged patients. It may was related that the reaction of micro-wakening in the elderly with OSAHS was less sensitive than in the non-aged.

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远程医疗在阻塞性睡眠呼吸暂停诊疗中的应用进展

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中华健康管理学杂志 2022年第4期16卷 283-286页

作者：裴果欧琼广东省人民医院(广东省医学科学院)广东省老年医学研究所睡眠中心广州510080

远程医疗有助于减轻老龄化社会中不断增加的慢性病相关的医疗负担。阻塞性睡眠呼吸暂停(OSA)远程医疗的目的是改善其疾病管理方式,提高持续气道正压通气(CPAP)的依从性,减轻其相关医疗费用负担。在OSA的管理中,应用远程医疗模式可以进... 详细信息

远程医疗有助于减轻老龄化社会中不断增加的慢性病相关的医疗负担。阻塞性睡眠呼吸暂停(OSA)远程医疗的目的是改善其疾病管理方式,提高持续气道正压通气(CPAP)的依从性,减轻其相关医疗费用负担。在OSA的管理中,应用远程医疗模式可以进行5G网络下的远程诊断、远程会诊,对接受CPAP治疗患者进行远程治疗和远程随访。

关键词：睡眠呼吸暂停阻塞性远程医学信息和通信技术

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阻塞性睡眠呼吸暂停患者接受治疗情况及其影响因素

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中华医学杂志 2018年第20期98卷 1578-1581页

作者：陈柏欣欧琼潘敏霞广东省人民医院广东省医学科学院广东省老年医学研究所呼吸科广州510000

目的调查阻塞性睡眠呼吸暂停（OSA）患者接受治疗情况，分析其影响因素。方法采用横断面调查方法，对2014年1月至2015年12月在广东省人民医院睡眠呼吸障碍中心诊断为OSA、具有完整联系方式的成人患者进行电话调查，完成问卷。内容包括... 详细信息

目的调查阻塞性睡眠呼吸暂停（OSA）患者接受治疗情况，分析其影响因素。方法采用横断面调查方法，对2014年1月至2015年12月在广东省人民医院睡眠呼吸障碍中心诊断为OSA、具有完整联系方式的成人患者进行电话调查，完成问卷。内容包括诊断后是否接受治疗、治疗方式、未治疗的原因、是否复诊等。结果共524例OSA患者具有完整联系方式，480例（91．6％）完成有效问卷，其中轻、中、重度OSA患者分别占60例（12．5％）、159例（33．1％）、261例（54．4％）；睡眠呼吸暂停低通气指数为（36．1±21．4）次／h。480例患者中200例（41．7％）接受治疗，其中184例（92．0％）接受持续气道正压通气治疗。轻度OSA、非肥胖、无日问嗜睡、女性患者治疗率更低；接受治疗还与入睡困难呈负相关。患者未治疗的主要原因是自我采用行为干预，其次是自认为无需治疗。18例（3．8％）患者诊断后曾至睡眠中心专科复诊，多为已接受治疗或自觉有憋醒症状者。结论OSA患者治疗率低，大部分患者诊断后未治疗，主要原因是患者自我采用行为干预和自认为无需治疗。

关键词：睡眠呼吸暂停,阻塞性治疗横断面研究

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财政竞争、引资竞争与土地约束性指标管控政策执行偏差

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中国人口·资源与环境 2018年第5期28卷 123-131页

作者：张绍阳刘琼欧名豪南京农业大学公共管理学院江苏南京210095

约束性指标管控是我国土地管理领域的一项重要公共政策,但其实际执行过程却偏离原定政策目标。传统"央地纵向委托代理困境"视角的解释认为,地方政府追求土地财政和土地引资的动机是导致产生政策执行偏差的根源,但其忽略了地方政府行为... 详细信息

约束性指标管控是我国土地管理领域的一项重要公共政策,但其实际执行过程却偏离原定政策目标。传统"央地纵向委托代理困境"视角的解释认为,地方政府追求土地财政和土地引资的动机是导致产生政策执行偏差的根源,但其忽略了地方政府行为所具有的空间关联性而存在解释力不足的缺陷。为此,本文立足于地方政府横向竞争的视角,分析了地方政府间的财政竞争、引资竞争对土地约束性指标管控政策执行的影响;在此基础上,通过2010—2014年间的省级面板数据,构建空间杜宾模型对相应理论假说进行了检验。研究发现:(1)地方政府的土地财政、土地引资行为会加剧本地区的政策执行偏差程度。(2)地方政府间存在"相互模仿"的土地财政和土地引资竞争策略,这使其土地财政和土地引资行为会产生正向的空间溢出,即在加剧本地区政策执行偏差程度的同时,还会同步加剧相邻地区的政策执行偏差程度。(3)土地引资的直接效应和间接效应无论在范围上还是强度上都要强于土地财政,这表明地方政府间的土地引资竞争是导致政策执行偏差的更重要因素。本研究的政策启示在于,为了促进土地约束性指标管控政策的良好执行,不仅要通过财税体制改革来弱化地方政府间的土地财政竞争,更要通过政府绩效考核改革来遏制它们之间的土地引资竞争。

关键词：土地约束性指标执行偏差土地财政竞争土地引资竞争空间杜宾模型

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外语教学中的文化导入问题

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湖南科技学院学报 2006年第10期27卷 225-227页

作者：欧琼湖南科技学院大学英语教学部湖南永州425100

本文结合外语教学中往往只注重语言知识的传授,而忽视相关文化背景知识的讲解给跨文化交际所带来种种弊端,阐明了外语教学中文化导入的重要性,并指出在外语教学中教师应该多渠道的向学生传授文化背景知识,学生也应该多方面的了解和掌握... 详细信息

本文结合外语教学中往往只注重语言知识的传授,而忽视相关文化背景知识的讲解给跨文化交际所带来种种弊端,阐明了外语教学中文化导入的重要性,并指出在外语教学中教师应该多渠道的向学生传授文化背景知识,学生也应该多方面的了解和掌握语言中蕴涵的文化信息,只有这样才能更好的实现语言学习的根本目的跨文化交际。

关键词：外语教学语言与文化文化导入跨文化乏际

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