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新型上肢手术辅助装置在C型臂机X-ray成像中的应用
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作者 吕廉威 谭云燕 +2 位作者 何秀丽 韦佳盈 罗冬兰 《中国科技期刊数据库 医药》 2024年第1期0135-0138,共4页
探究新型上肢手术辅助装置在C型臂机X-ray成像中的应用效果。方法 选取2022.10~2023.8南宁市第二人民医院五象医院住院的上肢手术患者60例,按照随机数字表法分为两组各30例,对照组:采取传统手术辅助装置进行上肢手术,观察组:新型多功能... 探究新型上肢手术辅助装置在C型臂机X-ray成像中的应用效果。方法 选取2022.10~2023.8南宁市第二人民医院五象医院住院的上肢手术患者60例,按照随机数字表法分为两组各30例,对照组:采取传统手术辅助装置进行上肢手术,观察组:新型多功能上肢手术辅助装置进行上肢手术,对比两组干预效果。结果 观察组巡回护士人工抬举悬吊肢体的时间、检查部位成像耗费时间短于对照组,C型臂X线机干扰次数少于对照组,P<0.05。结论:新型上肢手术辅助装置应用于C型臂机X-ray成像中能减少C型臂X线机干扰次数,缩短完成一个部位成像需要消耗时间,应用于上肢手术中整体操作简便、快捷,值得应用。 展开更多
关键词 上肢手术 辅助装置 c型臂机 x-ray成像
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Values of high-resolution computed tomography and pulmonary function tests in managements of patients with chronic hepatitis C virus infection 被引量:1
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作者 Oguzhan Okutan Zafer Kartaloglu +3 位作者 Ahmet Ilvan Ali Kutlu Erkan Bozkanat Emir Silit 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第3期381-384,共4页
AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomocjraphy (HRCT) in patients with chronic hepatitis C virus (HCV) infection. METHODS:Thirty-four patients with... AIM:To investigate pulmonary involvement via pulmonary function tests (PFT) and high-resolution computed tomocjraphy (HRCT) in patients with chronic hepatitis C virus (HCV) infection. METHODS:Thirty-four patients with chronic HCV infection without diagnosis of any pulmonary diseases and 10 healthy cases were enrolled in the study,PFT and HRCT were performed in all cases. RESULTS:A decrease lower than 80% of the predicted value was detected in vital capacity in 9/34 patients,in forced expiratory volume in one second in 8/34 patients,and in forced expiratory flow 25-75 in 15/34 patients,respectively.Carbon monoxide diffusing capacity (DLCO) was decreased in 26/34 patients.Findings of interstitial pulmonary involvement were detected in the HRCT of 16/34 patients.Significant difference was found between controls and patients with HCV infection in findings of HRCT (X^2=4.7,P=0.003).Knodell histological activity index (KHAI) of 28/34 patients in whom liver biopsy was applied was 9.0±4.7.HRCT findings,PFT values and DLCO were not affected by KHAI in patients with HCV infection.In these patients,all the parameters were related with age. CONCLUSION:We suggest that chronic hepatitis C virus infection may cause pulmonary interstitial involvement without evident respiratory symptoms. 展开更多
关键词 Respiratory Function Tests Tomography x-ray computed ADULT Aged FEMALE Hepatitis c chronic Humans Lung Diseases MALE Middle Aged
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Analysis of the 3C 445 soft X-ray spectrum as observed by Chandra high-energy gratings
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作者 Fu-Tong Dong Shu-Hua Shao +1 位作者 Yan Cheng Jiao-Long Zeng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第5期59-68,共10页
We present a detailed analysis of the soft X-ray emission of 3 C 445 using an archival Chandra High Energy Transmission Grating(HETG) spectrum. Highly-ionized H-and He-like Mg, Si and S lines, as well as a resolved ... We present a detailed analysis of the soft X-ray emission of 3 C 445 using an archival Chandra High Energy Transmission Grating(HETG) spectrum. Highly-ionized H-and He-like Mg, Si and S lines, as well as a resolved low-ionized Si Kα line, are detected in the high resolution spectrum. The He-like triplets of Mg and Si are resolved into individual lines, and the calculated R ratios indicate a high density for the emitter. The low values of G ratios indicate the lines originate from collisionally ionized plasmas. However, the detection of a resolved narrow Ne X radiative recombination continua(RRC) feature in the spectrum seems to prefer a photoionized environment. The spectrum is subsequently modeled with a photoionization model, and the results are compared with those of a collisional model. Through a detailed analysis of the spectrum, we exclude a collisional origin for these emission lines. A one-component photoionization model provides a great fit to the emission features. The best-fit parameters are log ξ = 3.3^+0.4-0.3 erg cm s^-1, n H = 5^+15 -4.5× 10^10 cm^-3 and NH = 2.5^+3.8 -1.7× 10^20 cm^-2.According to the calculated high density for the emitter, the measured velocity widths of the emission lines and the inferred radial distance(6 × 10^14-8 × 10^15 cm), we suggest the emission lines originating from matter are located in the broad line region(BLR). 展开更多
关键词 GALAXIES active - x-rays galaxies - galaxies individual (3c 445)
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万东C-3000大C臂HF SERIES GENERRATORS COMPACT X-RAY UNIT维修一例
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作者 木元章 《中国医学装备》 2005年第9期47-47,共1页
1故障现象: 在手术过程中透视时听见一爆破响声,操作者还看见计算机柜有黑烟冒出.高压控制液晶屏提示ERROR16和ERROR 33以及ERROR 52.操作人员在多次从启后三个错误代码依次出现,机器再也不能透视和曝光.
关键词 cOMPAcT SERIES x-ray ERROR HF c 维修 手术过程 高压控制
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A Narrow Band Chandra X-ray Analysis of SNR 3C 391
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作者 Yang Su Yang Chen 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2005年第4期412-418,共7页
We present narrow-band and equivalent width (EW) images of the thermal composite supernova remnant (SNR) 3C 391 in the X-ray emission lines of Mg, Si and S using the Chandra ACIS Observational data. The EW images ... We present narrow-band and equivalent width (EW) images of the thermal composite supernova remnant (SNR) 3C 391 in the X-ray emission lines of Mg, Si and S using the Chandra ACIS Observational data. The EW images reveal the spatial distribution of the emission of the metal species Mg, Si and S in the remnant. They have a clumpy structure similar to that seen in the broadband diffuse emission, suggesting that they are largely of interstellar origin. We find an interesting finger-like feature protruding outside the southwestern radio border of the remnant, somewhat similar to the jet-like Si structure found in the famous SNR Cas A. This feature may possibly be the debris of the jet of ejecta from an asymmetrical supernova explosion of a massive progenitor star. 展开更多
关键词 ISM: supernova remnants x-rays: ISM - x-rays: individual(3c 391)- ISM: lines and bands
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Impact of Heat Treatments and Hole Density (p) on the Structural, Electrical, and Superconducting Properties of LnSrBaCu3O6+z (Ln = Eu, Sm, Nd) Compounds
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作者 Mohammed Bellioua Mohamed Id El Amel +8 位作者 Fatima Bouzit Mohamed Errai Driss Soubane Aderrahim Ait Khlifa Mohammed Khenfouch Issam Mouhti Ahmed Tirbiyine Essediq Youssef El Yakoubi Abdelhakim Nafidi 《Communications and Network》 2023年第4期83-97,共15页
In this study, we thoroughly examined the impact of heat treatments and hole count (p) on the properties of LnSrBaCu<sub>3</sub>O<sub>6+z</sub> (Ln = Eu, Sm, Nd) compounds. We focused on prepar... In this study, we thoroughly examined the impact of heat treatments and hole count (p) on the properties of LnSrBaCu<sub>3</sub>O<sub>6+z</sub> (Ln = Eu, Sm, Nd) compounds. We focused on preparation, X-ray diffraction with Rietveld refinement, AC susceptibility, DC resistivity measurements, and heat treatment effects. Two heat treatment types were applied: oxygen annealing [O] and argon annealing followed by oxygen annealing [AO]. As the rare earth Ln’s ionic radius increased, certain parameters notably changed. Specifically, c parameter, surface area S, and volume V increased, while critical temperature Tc and holes (p) in the CuO<sub>2</sub> plane decreased. The evolution of these parameters with rare earth Ln’s ionic radius in [AO] heat treatment is linear. Regardless of the treatment, the structure is orthorhombic for Ln = Eu, tetragonal for Ln = Nd, orthorhombic for Ln = Sm [AO], and pseudo-tetragonal for Sm [O]. The highest critical temperature is reached with Ln = Eu (Tc [AO] = 87.1 K). Notably, for each sample, Tc [AO] surpasses Tc [O]. Observed data stems from factors including rare earth ionic size, improved cationic and oxygen chain order, holes count p in Cu(2)O<sub>2</sub> planes, and in-phase purity of [AO] samples. Our research strives to clearly demonstrate that the density of holes (p) within the copper plane stands as a determinant impacting the structural, electrical, and superconducting properties of these samples. Meanwhile, the other aforementioned parameters contribute to shaping this density (p). 展开更多
关键词 High-Tc Superconductors Heat Treatments Hole Density (p) Tc Parameter c Surface ab Electrical Resistance x-ray Diffraction
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CT在肺结核诊断中的价值 被引量:6
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作者 陈燕琴 杨均 +3 位作者 陈效友 陈冀 马玙 郑素华 《中国防痨杂志》 CAS 北大核心 2003年第6期374-376,378,共4页
目的 探讨CT对肺结核的诊断价值。方法 回顾性对比分析 98例具有完整临床资料的肺结核患者的胸部正侧位片、病灶断层及CT表现。结果  (1 )肺内病变主要分布于上叶尖后段及下叶背段 ,其次为上叶前段和下叶各基底段。(2 )胸部CT对肺内... 目的 探讨CT对肺结核的诊断价值。方法 回顾性对比分析 98例具有完整临床资料的肺结核患者的胸部正侧位片、病灶断层及CT表现。结果  (1 )肺内病变主要分布于上叶尖后段及下叶背段 ,其次为上叶前段和下叶各基底段。(2 )胸部CT对肺内隐蔽部位结核病变的显示率明显高于胸片及病灶断层 (P <0 .0 5)。 (3)胸部CT对病灶内钙化、纵隔内淋巴结肿大、纵隔内淋巴结钙化及肺气肿、肺大泡、限局性气胸的显示率明显高于另两项检查 (P <0 .0 5)。 (4)对各种形态阴影的显示无明显差异 (P >0 .0 5)。 展开更多
关键词 cT 肺结核 诊断 病灶断层
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三聚氰胺(C_3N_6H_6)的高压Raman与压致结构相变研究 被引量:3
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作者 马红安 赵永年 +4 位作者 贾晓鹏 潘跃武 崔启良 陈立学 邹广田 《光散射学报》 2004年第4期289-294,共6页
本文在8 7GPa压力范围内研究了三聚氰胺(C3N6H6)的高压原位Raman光谱。通过内、外Raman活性模的压致效应,发现在1 5GPa和6 0GPa压力下该分子晶体发生了压致结构相变。用空间群相关原理确认在1 5GPa压力下它从单斜相转变为三斜相;在6 0GP... 本文在8 7GPa压力范围内研究了三聚氰胺(C3N6H6)的高压原位Raman光谱。通过内、外Raman活性模的压致效应,发现在1 5GPa和6 0GPa压力下该分子晶体发生了压致结构相变。用空间群相关原理确认在1 5GPa压力下它从单斜相转变为三斜相;在6 0GPa压力下又发生了另一次结构相变。然后在室温高压条件下对三聚氰胺进行了原位同步辐射能量散射x-ray衍射实验(EDXD),在14 7GPa压力范围内,观察到常压下为单斜晶系的三聚氰胺经历了两次压致结构相变。在1 3GPa下,三聚氰胺分子晶体从单斜相转变为三斜相;在8 2GPa又转变为正交相。本实验结果为利用三聚氰胺碳氮有机分子晶体高温高压合成超硬C3N4共价晶体的研究提供了重要信息。 展开更多
关键词 c3N6H6压致结构相变 高压Raman 高压原位x-ray衍射
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正常国人女性乳腺的CT表现(附160例分析)
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作者 刘福强 张云亭 +3 位作者 刘松龄 孙浩然 张敬 郭宏 《医学影像学杂志》 2003年第8期552-555,共4页
目的 :研究正常女性乳腺的CT表现并分型 ,初步确立乳腺CT的常规检查方法。方法 :应用体部CT对 1 60例处于不同生理分期的健康女性进行乳腺CT检查 ,其中 5例行增强CT检查。测量增强前后各生理分期乳腺实质的CT值 ,并通过图像放大测量乳... 目的 :研究正常女性乳腺的CT表现并分型 ,初步确立乳腺CT的常规检查方法。方法 :应用体部CT对 1 60例处于不同生理分期的健康女性进行乳腺CT检查 ,其中 5例行增强CT检查。测量增强前后各生理分期乳腺实质的CT值 ,并通过图像放大测量乳晕及乳房其他部位皮肤的厚度。结果 :描述了正常乳腺的CT表现 ,并将其分为七型。通过对不同扫描体位的对比研究 ,我们认为俯卧位、1 0 0mA、1 .8s ,标准算法重建可以作为乳腺CT检查的常规检查技术。正常乳腺实质增强后增加的CT值为 1 1 .89± 6 .80HU。结论 :乳腺CT能够较好地显示乳腺本身及其周围的结构 。 展开更多
关键词 正常乳腺 体层摄影术 X线计算机
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脑内基底节区对称性低密度或异常信号的发病机理及CT-MR诊断
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作者 王新怡 董桂清 李爱银 《医学影像学杂志》 2003年第8期556-558,共3页
目的 :分析基底节区对称性低密度或异常信号的发病机理 ,加深对其CT MRI表现的认识。方法 :30例病人均行CT及MRI横轴位扫描。结果 :CT平扫均表现为两侧基底节区的对称性低密度 ,MRIT1 WI呈对称性低信号 ,T2 WI呈高信号。结论 :MRI能更... 目的 :分析基底节区对称性低密度或异常信号的发病机理 ,加深对其CT MRI表现的认识。方法 :30例病人均行CT及MRI横轴位扫描。结果 :CT平扫均表现为两侧基底节区的对称性低密度 ,MRIT1 WI呈对称性低信号 ,T2 WI呈高信号。结论 :MRI能更多地显示受累的部位 ,同时了解具有以上CT MRI表现的疾病范畴 。 展开更多
关键词 基底节 体层摄影术 X线计算机 磁共振成像
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三聚氰胺(C_3N_6H_6)分子晶体的压致结构相变研究
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作者 马红安 贾晓鹏 +7 位作者 崔启良 潘跃武 朱品文 郭伟力 陈力学 任国仲 刘景 邹广田 《核技术》 CAS CSCD 北大核心 2002年第10期873-878,共6页
本文通过对三聚氰胺 (C3N6 H6 )的室温高压原位同步辐射能量散射X -ray衍射实验(EDXD) ,在 14 .7GPa压力范围内 ,观察到常压下为单斜晶系的三聚氰胺经历了两次压致结构相变。在 1.3GPa下 ,三聚氰胺分子晶体从单斜相转变为三斜相 ;在 8.2... 本文通过对三聚氰胺 (C3N6 H6 )的室温高压原位同步辐射能量散射X -ray衍射实验(EDXD) ,在 14 .7GPa压力范围内 ,观察到常压下为单斜晶系的三聚氰胺经历了两次压致结构相变。在 1.3GPa下 ,三聚氰胺分子晶体从单斜相转变为三斜相 ;在 8.2GPa又转变为正交相。本实验结果为利用三聚氰胺碳氮有机分子晶体高温高压合成超硬C3N4 展开更多
关键词 三聚氰胺 分子晶体 c3N6H6 压致结构相变 同步辐射 高压原位x-ray衍射
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脑裂头蚴病的CT、MRI诊断 被引量:1
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作者 丁耀军 柳健 《江西科学》 2017年第5期698-701,共4页
目的:探讨脑裂头蚴病的临床及影像学表现,以提高本病的影像诊断水平。方法:回顾性分析15例手术病理证实的脑裂头蚴病的临床及影像学资料,所有患者均行CT检查,其中行MRI检查者13例。结果:脑裂头蚴病CT表现低密度灶伴点状钙化,不规则或点... 目的:探讨脑裂头蚴病的临床及影像学表现,以提高本病的影像诊断水平。方法:回顾性分析15例手术病理证实的脑裂头蚴病的临床及影像学资料,所有患者均行CT检查,其中行MRI检查者13例。结果:脑裂头蚴病CT表现低密度灶伴点状钙化,不规则或点状强化。MRI可见病灶区有串珠状增强或扭曲的条索样增强影。患者血清免疫学检查均显示曼氏裂头蚴抗体阳性。本组15例中11例在CT定位下行立体定向活检,4例经开颅手术预后均良好。结论:多数脑裂头蚴病的CT和MRI表现具有一定的特征性。血清免疫学检查在诊断脑曼氏裂头蚴病中起到重要作用。 展开更多
关键词 脑曼氏裂头蚴病 电子计算机断层扫描 磁共振成像 立体定向 免疫学检查
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基于三维几何实体的客车锤锻件锻模CAD系统
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作者 陈吉光 樊志新 宋宝韫 《锻压装备与制造技术》 北大核心 2004年第1期76-78,共3页
采用先进的三维实体造型软件SolidWorks,实现了客车常用锤锻零件的锻模计算机辅助设计系统,应用数据库及产品模型驱动技术,智能地完成设计任务。可克服传统设计的重复低效和不准确等缺点,系统简单、实用、可靠。
关键词 客车 锤锻件 锻模 cAD SOLIDWORKS
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膝关节慢性滑膜炎的CT研究 被引量:2
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作者 陈金英 王林森 《天津医药》 CAS 北大核心 2002年第10期603-605,共3页
目的 :探讨膝关节慢性滑膜炎CT表现及分型。方法 :回顾性分析关节镜或手术证实的89例和随访证实的178例膝关节慢性滑膜炎。结果 :根据CT表现将滑膜炎分为4型 :皱襞增生型153例 (197关节 ) ,积液型60例(89关节 ) ,单纯囊肿型19例 (19关节... 目的 :探讨膝关节慢性滑膜炎CT表现及分型。方法 :回顾性分析关节镜或手术证实的89例和随访证实的178例膝关节慢性滑膜炎。结果 :根据CT表现将滑膜炎分为4型 :皱襞增生型153例 (197关节 ) ,积液型60例(89关节 ) ,单纯囊肿型19例 (19关节 ) ,混合型35例 (50关节 )。40岁以上患者膝关节均伴有不同程度的骨质增生、关节退行性变 ,退行性变的程度与滑膜炎的类型无相关性。结论 :CT检查诊断膝关节慢性滑膜炎是较为可靠的方法 ,可直观关节内皱襞增生、积液以及囊肿形成的征象。 展开更多
关键词 膝关节 滑膜炎 慢性病 cT 鉴别 诊断
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脑梗死CT、MR与临床不符的原因分析
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作者 蒋华平 杨宏美 陈桂林 《中国临床医学影像杂志》 CAS 2002年第S1期10-11,共2页
目的:分析脑梗死CT、MR与临床不符的原因。方法:分析85例脑梗死的头颅CT、MR并与临床表现相对照。结果:不相符部位以基底节、脑叶、侧脑室旁脑白质多见,腔隙性脑梗死多见。不相符情况:CT(-)、MR(+),临床(-);CT(+)、MR(+),临床(-);CT(-)... 目的:分析脑梗死CT、MR与临床不符的原因。方法:分析85例脑梗死的头颅CT、MR并与临床表现相对照。结果:不相符部位以基底节、脑叶、侧脑室旁脑白质多见,腔隙性脑梗死多见。不相符情况:CT(-)、MR(+),临床(-);CT(+)、MR(+),临床(-);CT(-)、MR(+),临床(+)。CT、MR表现与临床同侧;CT、MR两侧,临床一侧;CT、MR一侧,临床两侧。结论:基底节、脑叶、侧脑室旁脑白质内腔隙性脑梗死CT、MR与临床不符者较多见。MR是诊断腔隙性脑梗死的首选检查手段。 展开更多
关键词 脑梗塞 体层摄影术 X线计算机 磁共振成像
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Crystal Structure and Thermodynamic Study of Ephedrine Hydrochloride C_(10)H_(16)NOCl(s) 被引量:2
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作者 YANG Wei-wei DI You-ying LI Jing KONG Yu-xia 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第2期304-308,共5页
The crystal structure of ephedrine hydrochloride was determined by means of X-ray crystallography. The crystal system of the compound is monoclinic, and the space group is P21. Unit cell parameters are a=0.7308(6) n... The crystal structure of ephedrine hydrochloride was determined by means of X-ray crystallography. The crystal system of the compound is monoclinic, and the space group is P21. Unit cell parameters are a=0.7308(6) nm, b=0.6124(5) nm, and c= 1.2618(11) nm; β=90°, β= 102°, and γ =90°; Z=2. Low-temperature heat capacities of the title compound were measured with an improved precision automated adiabatic calorimeter over a temperature range from 77 K to 396 K. A polynomial equation of the heat capacities as a function of temperature in the temperature region was fitted by the least-squares. Based on the fitted polynomial equation, the smoothed heat capacities and thermodynamic functions of the compound relative to the standard reference temperature 298.15 K were calculated and tabulated at the intervals of 5 K. 展开更多
关键词 Ephedrine hydrochloride c10H16NOcl(s) x-ray crystallography Adiabatic calorimetry Low-temperature heat capacity Thermodynamic function
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Solid polymeric electrolyte of poly(ethylene)oxide-50% epoxidized natural rubber-lithium triflate (PEO-ENR50-LiCF3SO3) 被引量:1
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作者 Siti Aminah bt. Mohd Noor Azizan Ahmad +1 位作者 Mohd. Yusri bin Abd. Rahman Ibrahim Abu Talib 《Natural Science》 2010年第3期190-196,共7页
A solid polymer electrolyte (SPE) films consist-ing of polyethylene oxide (PEO), 50% epoxi-dized natural rubber (ENR50) and LiCF3SO3 with various compositions of PEO-ENR50 and vari-ous weight percentage of LiCF3SO3 we... A solid polymer electrolyte (SPE) films consist-ing of polyethylene oxide (PEO), 50% epoxi-dized natural rubber (ENR50) and LiCF3SO3 with various compositions of PEO-ENR50 and vari-ous weight percentage of LiCF3SO3 were pre-pared by solution casting technique. The poly-mer electrolyte films were characterized using DSC, XRD and AC impedance spectroscopy. The SPE with the PEO-ENR50 composition of 70-30 shows the highest conductivity of 4.2 × 10-5 Scm-1 at the 15 wt.% of LiCF3SO3 compared with the other composition of PEO/ENR50. This composition was then chosen to investigate the effect of LiCF3SO3 on the thermal property, structure and conductivity of the electrolyte. The highest room temperature conductivity of 1.4 × 10-4 Scm-1 was achieved at 20 wt.% of LiCF3SO3. The conductivity result is supported by the DSC and XRD analysis which showed the semi- crystalline nature of PEO turning to amor-phous state due to the increase in LiCF3SO3 content. 展开更多
关键词 A. Polymers c. Differential Scanning cALORIMETRY (DSc) c. x-ray Diffraction D. ELEcTRIcAL conductivity D. ELEcTRIcAL Properties
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In situ XRD Studies on Heat-treated PtRu/C Nanocatalysts
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作者 LIU Juan-ying LI Zhi-lin +1 位作者 VOGEL Walter YANG Hui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第3期511-515,共5页
Extremely small PtRu/C nanocatalysts were prepared via a carbonyl route. A thorough in situ reduction X-ray structural characterization of these catalysts was performed. After synthesis and storage under ambient condi... Extremely small PtRu/C nanocatalysts were prepared via a carbonyl route. A thorough in situ reduction X-ray structural characterization of these catalysts was performed. After synthesis and storage under ambient condi- tions, the diffraction patterns of PtRu/C catalysts were seriously modified, indicating the surface oxide formation. In the reduced state, the particle size is around 2 nm. The observed relative fluctuations of lattice constants are 3%, which is far too large to be explained by a compositional fluctuation. Their origin is attributed to strong but isotropic strains and is related to the alloy formation. The annealing experiments show all the catalysts present an exceptional thermal stability when annealed in inert ambient, especially that of the Pt1Ru1/C catalyst. Besides, it is interesting to note that there is no thermal expansion evidence from the patterns. 展开更多
关键词 In situ x-ray diffraction PtRu/c nanocatalyst Thermal stability
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Integrated Product and Process Design Using a Reverse Engineering System
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作者 A Ajmal T S Tat 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期184-185,共2页
Computer-integrated manufacturing (CIM) and revers e engineering (RE) have changed drastically the concept of product re-design, pla nning and manufacture of components. However, the main problems currently facing the... Computer-integrated manufacturing (CIM) and revers e engineering (RE) have changed drastically the concept of product re-design, pla nning and manufacture of components. However, the main problems currently facing the developers of reverse engineering system, is the time consuming digitis ation of 3D data and the conversion of large amounts of data into a concise and manageable format and linking it to a CAD/CAM system. Automated 3-D profile gen eration, measurements and inspection of manufactured component represents one of the important functions in reverse engineering and in the improvements in produ ct quality in rapid product developments. The paper presents a novel methodology for the development of a reverse enginee ring technique for use in the rapid product development in a CIM environment . The system developed provides integration, data capture and manipulation, dat a transfer between a CAD, CAM, Computer-aided inspection (CAI) and a 3-D profi le scanning system. An efficient scanning strategy has been developed for scann ing and surfaces data acquisition. The products were scanned using a laser scann ing system with a dedicated scan control card and the associated software packag es. A versatile rig was developed for the ease of data gathering of the profile scanning process. The surface data collected was then used to build a mathematic al surface model, which was then used to develop a virtual 3-D model of the pro duct. The resulting surface model provides the geometrical input to the subseque nt machining operation using either a CNC system or other manufacturing operatio n e.g. dies casting/mould casting etc. The prototypes developed were inspected u sing a state-of-the art CNC-CMM that was integrated to the CAD/CAM system. Si nce the scanning/digitised data captured by laser scanning probes requires no ma nual editing, significant time saving over most non-contact probe systems was a chieved. Since the creation of an accurate CAD model of a redesigned component o r a prototype constitute a major element of the total turnaround time; maximum r eturn can be achieved by increasing the efficiency of the redesigning process. T he paper also outlines with a case study the application of the developed system . The system developed offers the flexibility of using the concept of reverse en gineering of a variety of components with the complimentary facility of integrat ion between CAD/CAM Computer-aided Inspection (CAI) systems and a scanning syst em. The developed reverse engineering application in an integrated manufacturing system can increase the consistency, improve cost-efficiency, reduce produ ct turn around and skill levels required to redesign, reengineer and prototyping components and products. 展开更多
关键词 rapid product development reverse engineering c omputer-Integrated Manufacturing (cIM) RE-ENGINEERING co-ordinate Measuring Machines (cMM)
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一种新型凝汽器铜管污垢状况在线监测仪 被引量:3
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作者 王恭 杨善让 +1 位作者 张海林 孙灵芳 《管道技术与设备》 CAS 2004年第1期13-15,共3页
目前 ,火力发电厂凝汽器大多采用定期清洗。提出了一种通过污垢热阻评定凝汽器铜管污垢状况的计算方法 ,设计了基于单片机系统的污垢热阻在线测量系统 ,有助于实现胶球清洗系统的在线优化、确定最佳清洗周期。测量系统设计合理。
关键词 凝汽器 胶球清洗 污垢热阻 单片机
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