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The internal friction peak correlated to the relaxation of Al antisite atoms in Fe-Al alloys
Fe-Al合金中与Al反位置原子弛豫有关的内耗峰

SUN Wei,WU Jie,HAN Fusheng,
孙蔚
,吴杰,韩福生

金属学报 , 2007,
Abstract: 利用内耗方法对Fe47Al53合金中Al反位置原子的运动特征进行了研究,在410℃附近观察到了一个与合金热历史相关的弛豫型内耗峰.在快冷样品中内耗峰高度明显高于慢冷样品时内耗峰的高度;而对于快冷样品,升温测量时内耗峰高度又明显高于随后的降温测量时内耗峰的高度,内耗峰高度表明该内耗峰与快冷时残留的缺陷有关.由于该内耗峰激活能为1.88 eV,与Fe47Al53合金中Fe空位的迁移能相当,因而该峰应产生于应力诱导下Al反位置原子在Fe空位之间的运动.
电压反峰对脉冲电容器寿命特性的影响  [PDF]
王博闻,李化,赖厚川,林福昌,李智威,刘德,李浩原,张钦
强激光与粒子束 , 2014,
Abstract: ?以金属化聚丙烯膜电容器电压反峰为研究对象,探讨了脉冲电流对电容器寿命的影响机制,通过对电容器在不同电压反峰系数下进行寿命测试,研究了电压反峰系数与电容器寿命之间的关系。研究结果表明:当电压反峰系数在10%~65%时,电容器寿命成指数下降。基于试验结果,通过统计分析的方法,拟合出寿命随电压反峰系数变化的经验公式,可以用来预测不同反峰系数下金属化聚丙烯膜电容器的寿命特性。
地基动力特性参数分析中的点峰法与多峰法
Point-peak and Multi-peak Methods for Analyzing Parametersof Dynamic Characteristics of Foundation
 [PDF]

吴邦达,吴丽波
- , 2015, DOI: 10.3969/j.issn.1000-0844.2015.01.0068
Abstract: 长期以来我国规定用点峰法分析动力基础线位移幅频响应曲线,但得出的地基阻尼比偏低,因而在动力基础设计规范中的阻尼比也偏低。经测试分析比较,提出多峰法可以提高地基阻尼比。多峰法已用于液压振动台基础设计,较为经济, 多年来使用良好。现对两个方法的区别包括刚度予以说明。
The point-peak method has been used for many years to analyze the linear displacement amplitude-frequency response curve of dynamic foundation. In this method, however, the subsoil damping ratio is low and is thus low in the code for dynamic foundation design.In this study, a multi-peak method is presented for measurement and analysis to increase the damping ratio.This method is used in the design of a hydraulic vibrator foundation with better economic results and has been also been used in well operation.This paper describes the differences in the two methods, including stiffness.The point-peak method has limitations.With increasing frequency, the damping ratio unusually decreases.The ratio value is zero at peak frequency but is 0.707 at the origin.Moreover, stiffness is larger at peak frequency but smaller at the origin.Therefore, the damping ratio is smaller in the peak area, and thus in our code for design of dynamic machine foundation, resulting in an excessively large and wasteful foundation.In addition, one parameter group is obtained by analyzing the single response curve with the point-peak method, and different groups from other curves of one foundation unusually appear because there is only one group for one foundation.On the contrary, in the multi-peak method, the parameters obtained by analyzing two curves, namely two by two, are generally very close and may be averaged.This method is more economical, and stiffness is decreased along an increase in frequency, and the static stiffness is larger than dynamic stiffness.This result agrees with the half space theory of foundation.The code for design of a dynamic machine foundation is mainly applied to the foundation design of a reciprocating compressor with a single working frequency.Resonance can be avoided if the natural frequency is larger or smaller than the working frequency.In such cases, the effect of damping is less, and the damping ratio may be small. In hydraulic vibrators with a wider working frequency zone, however, resonance cannot be avoided.In such cases, the damping ratio must be larger to control the resonance.
无 氧 条 件 下TiO2 薄 膜 界 面 光 催 化 反 应 的XPS 研 究  [PDF]
杨喜昆,胡显智,何 兵,楚国栋
分子催化 , 2009,
Abstract: 设 计 利 用 X 射 线 光 电 子 能 谱 仪 的 高 真 空 系 统 作 为 无 氧 条 件 下 光 催 化 反 应 和 分 析 的 场 所 , 研 究 真 空 无 氧 环 境 和 大 气 有 氧 环 境 中 紫 外 光 激 发 TiO2 薄 膜 表 面 的 光 催 化 反 应 , 并 对 无 氧 条 件 下 TiO2 薄 膜 降 解 亚 甲 基 蓝 进 行 初 步 探 索 . 结 果 表 明 , 在 大 气 有 氧 和 真 空 无 氧 条 件 下 TiO2 薄 膜 经 紫 外 光 照 后 , 表 面 的 化 学 组 成 和 化 学 状 态 均 发 生 了 变 化 ; 在 有 氧 环 境 中 TiO2 薄 膜 表 面 氧 含 量 增 加 , 而 在 无 氧 环 境 中 TiO2 薄 膜 表 面 氧 含 量 减 少 . TiO2 薄 膜 表 面 的 吸 附 氧 是 维 持 无 氧 条 件 下 光 催 化 反 应 的 重 要 原 因 , 增 加 薄 膜 表 面 吸 附 氧 的 含 量 能 提 高 TiO2 薄 膜 在 无 氧 环 境 中 的 催 化 活 性 . 此 外 , 无 氧 条 件 下 TiO2 薄 膜 降 解 亚 甲 基 蓝 光 催 化 反 应 过 程 中 , 亚 甲 基 蓝 分 子 只 是 脱 去 了 某 个 含 氮 的 基 团 , 生 成 了 中 间 产 物 , 而 并 没 有 完 全 降 解 .
Study on Chromatographic Peak Identification by Means of Peak Shape Analysis
峰形分析辅助色谱定性的研究

Cai Chunping,Liang Ming,Weng Ruorong,
蔡春平
,梁鸣,翁若荣

色谱 , 1999,
Abstract: A new method for chromatographic peak identification by means of peak shape analysis is presented in this paper. Directly measurable parameters, i. e. peak width and asymmetry factor are first utilized for peak shape analysis. It is showed from theoretical and experimental results that for a component having almost the same retention time with the standard, an overlapped peak can be obtained by injecting the mixture of analyte and standard. In comparing the peak shape of overlapped peak with the standard one, the component can be identified whether it is the same with the standard or not.
Fe-Al合金中与Al反位置原子弛豫有关的内耗峰  [PDF]
孙蔚,韩福生,吴杰
金属学报 , 2007,
Abstract: 利用内耗方法对Fe-Al合金中Al反位置原子的运动特征进行了研究。在410℃附近观察到了一个与合金热历史相关的弛豫型内耗峰,在快冷样品中内耗峰高度明显高于慢冷样品,而对于快冷样品,升温测量时内耗峰高度又明显高于随后的降温测量,这表明该内耗峰与快冷时残留的缺陷有关。由于该内耗峰激活能为1.88eV,与B2Fe-Al合金中Fe空位的迁移能相当,因此该峰应产生于应力诱导下Al反位置原子在Fe空位之间的运动。
INTERNAL FRICTION PEAK ASSOCIATED WITH GRAIN BOUNDARY IN Al BICRYSTALS
铝双晶晶界的内耗峰

GUAN Xingsheng,GE Tingsui Laboratory of Internal Friction,Defects in Solids,
关幸生
,葛庭燧

金属学报 , 1993,
Abstract: 用受迫振动法测量了夹角为60°和129.5°的铝双晶的内耗,都观测到一个温度内耗峰,峰巅温度是200℃左右(频率1Hz)激活能为0.88eV对于这个内耗峰的机制做了初步解释。
SIMULATION OF DSC CURVE AND COMPUTATION OF PEAK AREAS
DSC曲线的模拟及峰面积计算

Chen Shen-zhi,Lin Shao-fan,
陈慎之
,林少凡

高分子学报 , 1983,
Abstract: 差示扫描量热法(DSC)曲线峰面积的简便、准确地计算是热分析工作者所关注的。七十年代初Lind、Wendlandt等人曾设想用计算机处理数据。七十年代后期,国外已有DSC和微型机联用。但仍有采用求积仪(或面积计planimeter),并认为求积仪比“剪纸称重”法偏差低。
探究峰流速仪呼气峰流速检测对慢性阻塞性肺疾病的筛查效力
The Effectiveness of Peak Flow Meter in COPD Screening
 [PDF]

刘亚男,许文兵,孟淑珍,赵阳,官微微
- , 2015, DOI: 10.7507/1671-6205.2015062
Abstract: 目的探讨峰流速仪呼气峰流速(PEF)检测对不同程度慢性阻塞性肺疾病(简称慢阻肺)人群筛查的敏感性。 方法选取2013年5月至2014年12月在北京协和医院呼吸内科门诊确诊的156例慢阻肺患者,采集患者病史、症状、危险因素暴露史、近1年急性加重次数和合并症等资料,并进行6分钟步行测试,测评慢阻肺评估测试(CAT)、改良英国医学研究委员会呼吸问卷(mMRC)和圣乔治呼吸问卷(SGRQ)。同时采用肺功能仪测量通气功能以及峰流速仪测量PEF。 结果以PEF占预计值百分比(PEF%pred)=80%为截断值,156例患者中筛查出120例(76.9%),36例被判定为漏诊人群。影响慢阻肺人群能否被峰流速仪筛查出的因素为FEV1%pred与SGRQ总分(P<0.01)。PEF筛查慢阻肺患者的整体敏感性为76.9%,对轻度气流受限患者的敏感性为27.7%,对中度气流受限患者的敏感性为68.5%,对重度~极重度气流受限患者的敏感性为98.5%,对中度~极重度气流受限患者的敏感性为83.3%;对CAT<10患者的敏感性为48.3%,对mMRC<2患者的敏感性为60.0%,对SGRQ<25患者的敏感性为30.0%;对CAT≥10患者的敏感性为87.5%,对mMRC≥2患者的敏感性为90.9%,对SGRQ≥25患者的敏感性为90.0%;对A级患者的敏感性为35.2%,对B级患者的敏感性为75.0%,对慢阻肺高危人群(C~D级)的敏感性为95.9%。以80%为截断值,峰流速筛查对早期慢阻肺患者(肺功能GOLD 1级、症状轻、慢阻肺综合评估A级)的敏感性较低;当截断值调整为95%时,峰流速筛查对早期慢阻肺的敏感性大幅度升高。 结论峰流速检测是慢阻肺良好的筛查方法。峰流速能否筛查出慢阻肺患者,取决于患者的肺功能(FEV1%pred)与症状严重程度(SGRQ)。峰流速筛查能早期发现慢阻肺患者,对气流受限程度重、急性加重风险高、需要药物治疗以缓解症状的患者尤为敏感。
ObjectiveTo analyze the sensitivity of peak flow meter screening in different subgroups of chronic obstructive pulmonary disease (COPD). MethodsA total of 156 outpatients with COPD from Peking Union Medical Hospital from May 2013 to December 2014 were recruited in the study. Each patient's symptoms,history of exposure to risk factors,and the times of exacerbation in last year was recorded. All patients completed CAT,mMRC,the St George's Respiratory Questionnaire (SGRQ),6 minutes walking test,spirometry,and peak expiratory flow (PEF) by peak flow meter. ResultsUsing the cut-off of PEF%pred=80%,the PEF detected 120 COPD patients in 156 subjects. The predictive factors of abnormal PEF%pred in COPD was FEV1%pred and the total score of SGRQ (P<0.05). PEF screening could identify 76.9% of COPD patients,30.0%-60.0% of patients of less symptoms (mMRC<2 or CAT<10 or SGRQ<25),83.3%-90.9% of COPD patients with more symptoms (mMRC ≥ 2 or CAT ≥ 10 or SGRQ ≥ 25),27.7% of COPD patients with mild airflow limitation,68.5% of COPD patients with moderate airflow limitation,83.3% of COPD patients with moderate to very severe airflow limitation. When grouped by GOLD combined assessment method,PEF screening could identify 35.2% of patients of group A,75.0% of patients of group B,and 95.9% of patients of group C and D. The cut-off value of PEF% pred=80% showed low sensitivity to early stage of COPD,but when using the cut-off value of PEF% pred=95%,that sensitivity increased signifcantly. ConclusionsPeak flow meter may be used as a tool to screen COPD. It can identify part of COPD patients especially for those patients with more symptoms,requiring regular treatment,with deteriorated pulmonary function and high risk of
PEAK-SWITCHING OF THE PHOTOELECTRON SPECTRUM
光电子谱的峰开关效应

YAO GUAN-HUA,XU ZHI-ZHAN,
姚关华
,徐至展

物理学报 , 1989,
Abstract: The photoelectron spectrum from autoionizing atoms in strong laser field is investigated on the basis of ref 12] . Peak-switching similar to the corresponding effect in strong field multiphoton ionization is found, implying that the second-order ionization processes and high-order photoelectron peaks play essential roles in strong laser-field induced autoionization-These results show that many of previous results need to be revised.
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