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Influence of aging modes on microstructure and mechanical properties of AZ80 magnesium alloy

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China Foundry 2007年第4期4卷 296-299页

作者： ZHANG ju-mei JIANG Bai-ling WANG Zhi-hu YUAN Sen NAN Hong-qiang LUO Hong-bin School of Materials Science and Engineering Xi＇an University of Technology Xi＇an 710048 China Department of Materials Science and Engineering Xi＇an University of Science ＆ Technology Xi＇an 710054 China

The microstructure and mechanical properties of AZ80 magnesium alloy after solid solution and aging treatments were studied by using optical microscope （OM）, X-ray diffraction （XRD）, scanning electron microscopy （SEM） as well as tensile testing. The results indicated that β-Mg17Al12 phase was getting to distribute discontinuously along the grain boundary after treated at 395℃ ageing for 12 h followed by water-cooling, but it did not dissolve into α-Mg completely. The residualβ-Mg17Al12 phase distributed along the grain boundary and had block-like or island shapes. The size of α-Mg was getting to be coarsening but not significantly. The β-Mg17Al12 precipitates appeared in discontinuous and continuous pattems from supersaturated α-Mg solid solution after aged at 200℃. The precipitation patterns were associated with the aging time essentially. The tensile strength and elongation of the alloy increased significantly but the hardness and yield strength decreased after solid solution treatment. However, with the prolonging of aging time, the hardness and strength of alloy increased while the ductility decreased.

关键词： magnesium alloy solid solution aging treatment microstructure mechanical property

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创伤叙事与文学救赎——谢宏创作论

中国文学研究 2021年第1期 168-173页

作者：鞠梅深圳大学国际交流学院广东深圳518060

个体性创伤在人的成长过程中会留下不可磨灭的"踪迹",对创伤进行文学重构和讲述,不仅有助于作家探究个体创伤的形成路径,也有助于和读者一起烛照创伤形成的共同性经验,从而将个体性创伤经验转化为群体性创伤叙事。深圳作家谢宏通过文学... 详细信息

个体性创伤在人的成长过程中会留下不可磨灭的"踪迹",对创伤进行文学重构和讲述,不仅有助于作家探究个体创伤的形成路径,也有助于和读者一起烛照创伤形成的共同性经验,从而将个体性创伤经验转化为群体性创伤叙事。深圳作家谢宏通过文学作品展现了大量"创伤经验",这种创伤叙事,既是对自我的追寻,更是以个体发声的方式描绘了一代人的共同际遇,使得读者藉此去关注个体创伤和原生家庭。

关键词：谢宏创伤叙事原生家庭文学救赎

Using nutritional assessment to predict gender-specific risks of sarcopenia among the elderly receiving health check-up in Taipei

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Journal of Geriatric Cardiology 2016年第3期13卷 261-266页

作者： Ya-Hui HUANG Yi-Fen LIN mei-ju CHEN Food and Nutrition Department Heping Fuyou Branch of Taipei City Hospital Taiwan China Department of Family Medicine Heping Fuyou Branch of Taipei City Hospital Taiwan China College of Healthcare Administration and Management National Taipei University of Nursing and Health Science Taiwan China

Quality of life for the elderly in an ageing society is receiving more attention than ever. After age 40, muscle mass loses at the rate of 3% to 8% every 10 years. More- over, the decline intensifies after 60 years old. Although many people do not experience changes in total body weight, their muscle mass is slowly replaced by body fat. Decreased muscle mass means lower muscle strength, which affects physical functioning. As a result, daily activities become con- strained, risks of fall and bone fracture elevated,

关键词： Gender Mini-nutritional assessment Sarcopenia

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小波和余弦变换的电机轴承故障特征参数构造

中北大学学报（自然科学版） 2017年第2期38卷 191-195,201页

作者：原菊梅太原工业学院自动化系山西太原030008

针对传统故障诊断特征参数的应用缺陷,提出了一种小波和余弦变换的感应电机轴承故障特征参数提取方法.首先,根据感应电机轴承振动信号的特点选择合适的小波滤波器和信息代价函数,并将感应电机轴承振动信号分解到各个不同的频域子空间;然... 详细信息

针对传统故障诊断特征参数的应用缺陷,提出了一种小波和余弦变换的感应电机轴承故障特征参数提取方法.首先,根据感应电机轴承振动信号的特点选择合适的小波滤波器和信息代价函数,并将感应电机轴承振动信号分解到各个不同的频域子空间;然后,基于离散余弦变换的频域能量聚集性对分解后的信号构造感应电机轴承故障特征参数,并对实际感应电机轴承正常、内圈故障、外圈故障和滚珠故障4种状态的振动信号进行分析,验证了所构造的特征参数能有效地实现电机轴承的早期故障检测与诊断;最后,与传统故障诊断特征参数方法进行了比较,说明所提出的特征参数构造方法对于感应电机轴承早期故障的诊断优于传统故障诊断特征参数方法.

关键词：小波包离散余弦变换故障诊断电机轴承

多用户MCDS-CDMA系统中的时频域信道估计方法

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电子与信息学报 2008年第10期30卷 2537-2540页

作者：居美艳冉明河海大学计算机及信息工程学院南京210098 伸兴通讯公司南京210012

该文提出了一种用于多用户MC DS-CDMA系统的信道估计方法,该方法在平均时域估计的基础上迭代一次平均频域信道估计,较好地改善了信道估计的性能。仿真结果表明,经过平均时域信道估计方法能较大程度地滤除多址干扰(MAI)和噪声,提高信道... 详细信息

该文提出了一种用于多用户MC DS-CDMA系统的信道估计方法,该方法在平均时域估计的基础上迭代一次平均频域信道估计,较好地改善了信道估计的性能。仿真结果表明,经过平均时域信道估计方法能较大程度地滤除多址干扰(MAI)和噪声,提高信道估计的准确性。再经过迭代一次平均频域信道估计,系统的误码率(BER)性能还可进一步改善,经过两次信道估计,系统取得的性能已很接近理想估计的性能。

关键词： MC DS—CDMA 信道估计时域信道估计频域信道估计

MC DS-CDMA系统中的常模盲检测方法

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通信学报 2007年第3期28卷 47-51页

作者：居美艳酆广增河海大学计算机及信息工程学院江苏南京210098 南京邮电大学通信与信息工程学院江苏南京210003

提出了MC DS-CDMA(多载波直扩码分多址)系统中的SDCMA(最陡下降常模算法)和LSCMA(最小二乘常模算法)的盲检测方法,并把这2种CMA(常模算法)盲检测和基于子空间的MMSE(最小均方误差)检测方法相比较。仿真结果表明这2种CMA盲检测方法性能... 详细信息

提出了MC DS-CDMA(多载波直扩码分多址)系统中的SDCMA(最陡下降常模算法)和LSCMA(最小二乘常模算法)的盲检测方法,并把这2种CMA(常模算法)盲检测和基于子空间的MMSE(最小均方误差)检测方法相比较。仿真结果表明这2种CMA盲检测方法性能明显优于基于子空间的MMSE检测方法,而且运算复杂度也低于后者。在收敛速度上,LSCMA检测方法远快于SDCMA检测方法。

关键词：多载波直扩码分多址最陡下降常模算法最小二乘常模算法子空间

一种联合均衡和多用户检测的SDCMA盲算法

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电子与信息学报 2006年第8期28卷 1403-1407页

作者：居美艳酆广增南京邮电学院通信工程系南京210003

该文提出了用于MCDS-CDMA系统中的两种SDCMA(最陡下降常模算法)盲检测方法,一种是SDCMA盲均衡算法,在此基础上,提出了另一种联合均衡和多用户检测的SDCMA盲算法。同时还将这两种算法与基于子空间的MMSE(最小均方误差)盲检测算法进行比... 详细信息

该文提出了用于MCDS-CDMA系统中的两种SDCMA(最陡下降常模算法)盲检测方法,一种是SDCMA盲均衡算法,在此基础上,提出了另一种联合均衡和多用户检测的SDCMA盲算法。同时还将这两种算法与基于子空间的MMSE(最小均方误差)盲检测算法进行比较。仿真结果表明,这两种SDCMA算法的BER(误比特率)性能均优于子空间法,而且联合均衡和多用户检测的SDCMA盲算法利用同时对均衡权值向量和多用户检测器向量进行自适应更新,能较大程度地改善系统性能,是这3种盲算法中性能最佳的一个。

关键词：多载波直扩码分多址最陡下降常模算法均衡多用户检测

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铋膜电极伏安法测定苏丹红Ⅰ号

化学研究与应用 2007年第7期19卷 838-840页

作者：杜美菊商丘师范学院化学系河南商丘476000

The electrochemical of sudanⅠat an bismuth-film electrode has been *** the buffer solution of HAc-NaAc and ethanol(pH = 4.0),sudanⅠproduces an reductive peak at-0.5V,peak current showed a well linear relationship with concentration of sudanⅠin the range of 1.7×10-6mol/L～5.9×10-5mol/L,and to regression equation to ip =4.862+ 7.374C(×10-6mol/L),r=0.9978。 The limit of the detection is 8.1×10-7mol/*** method can be applied to detemine sudanⅠ.

关键词：苏丹红Ⅰ号铋膜电极循环伏安法差分脉冲伏安法

Common bile duct injury by fibrin glue: Report of a rare complication

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World Journal of Gastroenterology 2015年第9期21卷 2854-2857页

作者： Yu-Long Yang Cheng Zhang Hong-Wei Zhang Ping Wu Yue-Feng Ma mei-ju Lin Li-jun Shi Jing-Yi Li Mu Zhao Department of Biliary Minimally Invasive Surgery Affiliated Zhongshan Hospital of Dalian University

Fibrin glue is widely used in clinical practice and plays an important role in reducing postoperative *** report a case of a 65-year-old man, whose common bile duct was injured by fibrin glue, with a history of failed laparoscopic cholecystectomy and open operation for uncontrolled laparoscopic *** view of thepersistent liver dysfunction, xanthochromia and skin itching, the patient was admitted to us for further ***, computed tomography, and magnetic resonance cholangiopancreatography(MRCP) revealed multiple stones in the common bile duct, and liver function tests confirmed the presence of obstructive jaundice and liver *** retrograde cholangiopancreatography was unsuccessfully performed to remove choledocholithiasis, but a small amount of tissue was removed and pathologically confirmed as calcified biliary *** was followed by open surgery for suspicious *** was no evidence of cholangiocarcinoma, but the common bile duct wall had a defect of 8 mm × 10 mm at Calot's triangle.A hard, grid-like foreign body was removed, which proved to be solid fibrin ***, the residual choledocholithiasis was removed by a choledochoscopic procedure, and the common bile duct deletion was repaired by liver round ligament with T-tube *** months later, endoscopy was performed through the T-tube fistula and showed a well-repaired bile duct *** months later, MRCP confirmed no bile duct stenosis.A review of reported cases showed that fibrin glue is widely used in surgery, but it can also cause organ *** mechanism may be related to discharge reactions.

关键词： Fibrin glue Laparoscopic cholecystectomy Choledoch