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Comparison of efficacy of lung ultrasound and chest X-ray in diagnosing pulmonary edema and pleural effusion in ICU patients: A single centre, prospective, observational study
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作者 Kunal Tewari Sumanth Pelluru +5 位作者 Deepak Mishra Nitin Pahuja Akash Ray Mohapatra Jyotsna Sharma Om Bahadur Thapa Manjot Multani 《Open Journal of Anesthesiology》 2024年第3期41-50,共10页
Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LU... Background and Aims While chest X-ray (CXR) has been a conventional tool in intensive care units (ICUs) to identify lung pathologies, computed tomography (CT) scan remains the gold standard. Use of lung ultrasound (LUS) in resource-rich ICUs is still under investigation. The present study compares the utility of LUS to that of CXR in identifying pulmonary edema and pleural effusion in ICU patients. In addition, consolidation and pneumothorax were analyzed as secondary outcome measures. Material and Methods This is a prospective, single centric, observational study. Patients admitted in ICU were examined for lung pathologies, using LUS by a trained intensivist;and CXR done within 4 hours of each other. The final diagnosis was ascertained by an independent senior radiologist, based on the complete medical chart including clinical findings and the results of thoracic CT, if available. The results were compared and analyzed. Results Sensitivity, specificity and diagnostic accuracy of LUS was 95%, 94.4%, 94.67% for pleural effusion;and 98.33%, 97.78%, 98.00% for pulmonary edema respectively. Corresponding values with CXR were 48.33%, 76.67%, 65.33% for pleural effusion;and 36.67%, 82.22% and 64.00% for pulmonary edema respectively. Sensitivity, specificity and diagnostic accuracy of LUS was 91.30%, 96.85%, 96.00% for consolidation;and 100.00%, 79.02%, 80.00% for pneumothorax respectively. Corresponding values with CXR were 60.87%, 81.10%, 78.00% for consolidation;and 71.3%, 97.20%, 96.00% for pneumothorax respectively. Conclusion LUS has better diagnostic accuracy in diagnosis of pleural effusion and pulmonary edema when compared with CXR and is thus recommended as an effective alternative for diagnosis of these conditions in acute care settings. Our study recommends that a thoracic CT scan can be avoided in most of such cases. 展开更多
关键词 Chest x ray (CxR) CONSOLIDATION Pulmonary edema Pleural effusion Lung ultrasound (LUS) PNEUMOTHORAx
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Study of NdCl_3-FeCl_3-Graphite Intercalation Compounds by X-Ray Photoelectron Spectroscopy 被引量:1
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作者 侯仰龙 韦永德 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第1期18-20,共3页
NdCl 3 FeCl 3 graphite intercalation compounds were synthesized by molten salt exchange method. The state of the intercalates and the relative contents of Nd, Fe, Cl, C in the product were determined by X ray ph... NdCl 3 FeCl 3 graphite intercalation compounds were synthesized by molten salt exchange method. The state of the intercalates and the relative contents of Nd, Fe, Cl, C in the product were determined by X ray photoelectron spectroscopy(XPS). From the XPS data, it is concluded that the binding energy of Fe2p electrons is about 711 20~710 3 eV, the binding energy of Nd3d electrons is about 983 08~983 20 eV, and Fe in the product has two valence states (Fe 3+ and Fe 2+ ). 展开更多
关键词 rare earths neodymium chloride graphite intercalation compounds x ray photoelectron spectroscopy
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联合应用近红外线、高频超声、钼靶x—ray对乳腺癌的早期诊断分析 被引量:3
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作者 张明明 陈艾江 《中国中医药咨讯》 2011年第10期107-107,共1页
目的:比较应用近红外线、高频超声、钼靶x—ray各自对乳腺癌早期诊断的价值,探讨联合应用近红外线、高频超声、钼靶x—ray对乳腺癌早期诊断的价值。方法:对81例经近红外线扫描、经B超检查、钼钯X线检查的病例进行回顾性总结,对三种... 目的:比较应用近红外线、高频超声、钼靶x—ray各自对乳腺癌早期诊断的价值,探讨联合应用近红外线、高频超声、钼靶x—ray对乳腺癌早期诊断的价值。方法:对81例经近红外线扫描、经B超检查、钼钯X线检查的病例进行回顾性总结,对三种影像学方法在乳腺癌诊断中的价值和优缺点进行了分析比较。结论诊断符合率分别为:近红外线83%,B超92.5%,钼钯X线93%,联合应用96%。联合应用近红外线、高频超声、钼靶x—ray有助于提高乳腺癌的诊断率和判断手术范围及术后效果,具有较大的临床价值。 展开更多
关键词 乳腺癌 联合应用近红外线 高频超声 钼靶xray 早期诊断
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胞元结构X-Ray三维成像及其FEM模拟
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作者 杜凤山 Gao Y X +4 位作者 Hamilton R W 臧新良 Wang Y Lee P D Song Jim 《固体力学学报》 CAS CSCD 北大核心 2006年第4期399-402,共4页
采用微纳米X-Ray断面成像技术,通过对含有CaCl2生物淀粉膨化结构材料三维成像规律的研究,确定了胞元体结构形态,并分析了断层胞元分布规律.建立了带有微细孔洞结构材料三维几何描述模型,通过理论建模和数字编程实现了与非线性有限元的连... 采用微纳米X-Ray断面成像技术,通过对含有CaCl2生物淀粉膨化结构材料三维成像规律的研究,确定了胞元体结构形态,并分析了断层胞元分布规律.建立了带有微细孔洞结构材料三维几何描述模型,通过理论建模和数字编程实现了与非线性有限元的连接,分析了微米级胞体材料受载后的场变量分布. 展开更多
关键词 微纳米xray 胞无结构 非线性有限元模拟
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Xray Diffraction Data and Rietveld Structure Refinement for CeNi_5Sn
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作者 何维 曾令民 +1 位作者 区向丽 吴自勤 《Journal of Rare Earths》 SCIE EI CAS CSCD 1999年第3期234-236,共3页
The compound CeNi 5Sn was studied by means of X ray powder diffraction technique and refined by Rietveld method. It has a hexagonal structure with space group P 6 3/ mmc (No.194), Z =4, the lattice constant... The compound CeNi 5Sn was studied by means of X ray powder diffraction technique and refined by Rietveld method. It has a hexagonal structure with space group P 6 3/ mmc (No.194), Z =4, the lattice constants a =0 48912(3) nm, c =1 973(2) nm and D x=8 974 g·cm -3 . The Rietveld structural refinement was performed, leading to R p=0 138 and R wp =0 185. The figure of merit F N for the XRD data is F 30 =82 1(0 0068, 54). The X ray powder diffraction data are presented. 展开更多
关键词 Rare earths CeNi 5Sn x ray diffraction Rietveld structural refinement
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Crystal Structure and X-ray Powder Diffraction Data for Rare Earth Compound PrNiSn
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作者 吴世伟 曾令民 +3 位作者 谭立真 张丽萍 严嘉琳 郝建民 《Rare Metals》 SCIE EI CAS CSCD 1999年第1期56-60,共5页
The compound PrNiSn was studied by X ray powder diffraction technique. The crystal structure and the X ray diffraction data for this compound at room temperature were reported. The compound PrNiSn is orthorhombic wi... The compound PrNiSn was studied by X ray powder diffraction technique. The crystal structure and the X ray diffraction data for this compound at room temperature were reported. The compound PrNiSn is orthorhombic with lattice parameters a =0.74569(3) nm, b =0.76851(5) nm, c =0.45676(8) nm, V =0.26176 nm 3, Z =4 and D x=8.076 g·cm -3 , space group Pna2 1(33). The figure of merit F N for the compound is F 30 =54 (0.0093, 60). 展开更多
关键词 PrNiSn x ray diffraction data Crystal structure
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X-ray Powder Diffraction Data and Structural Parameters for Compound NdFe_0.6Sb_2
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作者 曾令民 覃文 +2 位作者 吴世伟 郝建民 农亮勤 《Rare Metals》 SCIE EI CAS CSCD 1997年第2期49-53,共5页
The compound NdFe 0.6 Sb 2 was studied by means of X ray powder diffraction. The X ray powder diffraction data and structural parameters demonstrated that this compound is of the tetragonal structure with space... The compound NdFe 0.6 Sb 2 was studied by means of X ray powder diffraction. The X ray powder diffraction data and structural parameters demonstrated that this compound is of the tetragonal structure with space group P4/nmm, Z =2 and D x=7.615 g·cm -3 . The lattice parameters are a =0.43499 (1) nm and c =0.97083 (4) nm. Refinement was performed with 42 reflections. 展开更多
关键词 x ray powder data NdFe 0.6 Sb 2 Crystal structure
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DIFFERENTIAL SCANNING CALORIMETRY AND X-RAY DIFFRACTION STUDIES ON AGING BEHAVIOR OF Zn-Al ALLOYS 被引量:2
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作者 X.L. Xu, Z. W. Yu, S.J. Ji, J.C. Sun and Z.K. Hei (Dalian Maritime University, Dalian 116024, China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2001年第2期109-114,共6页
Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities o... Decomposition processes of the quenched Zn-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities of supersaturated solid solution (SSS) of Zn-Al alloy and α' phase formed by quenching would reduce with the increase of Zn content and the precipitation of η-Zn phases even when aging at ambient temperature, so that the exothermic precipitation peak in DSC curve would disappear. The activation energy of the η-Zn precipitation and the reaction enthalpy were calculated and measured. The kinetics of α' decomposition or η-Zn formation was determined by XRD. The microstructure change during aging was observed by TEM. 展开更多
关键词 Aging of materials Aluminum alloys Differential scanning calorimetry x ray diffraction
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X-ray Powder Diffraction Data and Crystal Structure of NiSbY
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作者 曾令民 李均钦 +2 位作者 张丽萍 庄应烘 郝建民 《Rare Metals》 SCIE EI CAS CSCD 1996年第1期67-70,共4页
X-ray powder diffraction data and crystal structure of NiSbY compound were studied by X-ray powderdiffraction. The compound belongs to the space group F43 m with MgAgAs structure type, and the parameters Z=4, a=0.6307... X-ray powder diffraction data and crystal structure of NiSbY compound were studied by X-ray powderdiffraction. The compound belongs to the space group F43 m with MgAgAs structure type, and the parameters Z=4, a=0.63075(2) nm. 展开更多
关键词 ANTIMONY Crystal structure DIFFRACTION NICKEL x rays YTTRIUM
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Nested grazing incidence optics for x ray detection
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作者 李林森 强鹏飞 +5 位作者 盛立志 刘永安 刘哲 刘舵 赵宝升 张淳民 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第10期152-156,共5页
Grazing incidence optics (GIO) is the most important compound in an x-ray detection system; it is used to concentrate the x-ray photons from outer space. A nested planar GIO for x-ray concentration is designed and d... Grazing incidence optics (GIO) is the most important compound in an x-ray detection system; it is used to concentrate the x-ray photons from outer space. A nested planar GIO for x-ray concentration is designed and developed by authors in this paper; planar segments are used as the reflection mirror instead of curved segments because of the simple process and low cost. After the complex assembling process with a special metal supporter, a final circle light spot of φ 12 mm was obtained in the visible light testing experiment of GIO; the effective area of 1710.51 mm^2@ 1 keV and 530 mm^2@8 keV is obtained in the x-ray testing experiment with the GIO-SDD combination, which is supposed to be a concentrating detector in xray detection systems. 展开更多
关键词 x ray detection grazing incidence optics planar segments concentrating detector
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X-ray elastic constant determination and residual stress of two phase TiAl-based intermetallic alloy
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作者 郭富安 张永刚 +2 位作者 陈昌麒 ZHANG Yong-gong CHEN Chang-qi 《中国有色金属学会会刊:英文版》 CSCD 2001年第2期205-209,共5页
To evaluate the residual stress in TiAl based alloys by X ray diffraction, X ray elastic constants (REC) of a γ TiAl alloy were determined. From these results, the stress state of a given phase in a duplex TiAl based... To evaluate the residual stress in TiAl based alloys by X ray diffraction, X ray elastic constants (REC) of a γ TiAl alloy were determined. From these results, the stress state of a given phase in a duplex TiAl based alloy under a uniaxial tensile loading has been characterized by X ray diffraction. The results show that the X ray elastic constants and the microscopic stresses of the given phase are different from the apparent elastic constants and the macroscopic stresses of the alloy. The reason of the different distribution of the alloy was also discussed. [ 展开更多
关键词 TiAl based alloy x ray diffraction technique x ray elastic constant duplex structure residual stress
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The Characteristics and Dynamic Changes of X Ray Chest Film in 50 Patients with Severe Acute Respiratory Syndrome
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作者 马俊义 李智岗 +2 位作者 赵增毅 孙武装 王颖 《Chinese Journal of Integrated Traditional and Western Medicine》 2003年第4期296-298,共3页
关键词 in The Characteristics and Dynamic Changes of x ray Chest Film in 50 Patients with Severe Acute Respiratory Syndrome SARS
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BACKGROUND RECTIFICATION AND FEATURE EXTRACTION OF IMAGE IN A SPOT WELD OF AL ALLOY X-RAY DETECTION
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作者 T.Gang J.Zhang M.B.Zhang and F.X.Liu (1)AWPT National Key.,HIT,Harbin 15001,China 2)State 159 Factory,China) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第1期75-79,共5页
A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defec... A primary study on Processing in X - ray inspection of spot weld for aluminum alloy spot welding,in- cluding for background simulation,acquisition of ideal binary image, and extraction and identifi- cation of defect features was presented. 展开更多
关键词 x - ray detection image processing spot weld aluminium alloy
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探讨能量色散型X—ray测试仪不同准直器对检测项链中贵金属含量的影响
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作者 王燕 刘林林 《现代测量与实验室管理》 2016年第5期3-7,共5页
本文使用能量色散型X射线荧光光谱分析仪(简称X—ray测试仪)在确保仪器其他条件均相同的情况下,通过设置不同的准直器检测同一项链的同一位置,结果显示准直器的大小对测试结果有较显著的影响。
关键词 xray 准直器 项链
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X射线离体照射人体淋巴细胞诱发染色体畸变的剂量-效应关系 被引量:2
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作者 张连珍 邓志诚 +3 位作者 李云华 詹江海 金璀珍 刘秀林 《辐射防护》 CAS CSCD 北大核心 1989年第3期-,共4页
本文介绍用180kV X射线离体照射人体淋巴细胞诱发染色体畸变的剂量-效应关系的实验结果。实验设9个剂量点(0.1—5.0Gy)和1个对照点(0Gy)。分析结果表明,在(?)剂量范围内。双着丝点体加三着丝点体的畸变率 Y_1(%)、无着丝点断片畸变率 Y_... 本文介绍用180kV X射线离体照射人体淋巴细胞诱发染色体畸变的剂量-效应关系的实验结果。实验设9个剂量点(0.1—5.0Gy)和1个对照点(0Gy)。分析结果表明,在(?)剂量范围内。双着丝点体加三着丝点体的畸变率 Y_1(%)、无着丝点断片畸变率 Y_2(%)和总畸变率 Y_3(%)与剂量 D(Gy)的关系宜分别拟合为下列方程:Y_1=-0.336+3.89D+4.49D^2(适用于0.1~5.0Gy);Y_2=0.811+2.15D+2.77D^2;Y_3=0.6(?)5.7D+7.66D^2。在低剂量(0—0.5Gy)范围内,双着丝点体的畸变率Y_(dic)(%)和无着丝点断片畸变率 Y_(Ac)·(%)与剂量 D(Gy)的关系,可分别拟合为 Y_(dic)=-0.0013+4.02D(适用于0.1—0.5Gy),(?)=0.218+4.74D。 展开更多
关键词 染色体畸变 x射线 剂量 效应 淋巴细胞 生物剂量计
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Fe_(100-x)Co_x系合金超细粉末的制备和磁性 被引量:3
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作者 任晓燕 何正明 +2 位作者 钟敏建 张正明 丛伟艳 《上海大学学报(自然科学版)》 CAS CSCD 2003年第3期217-220,共4页
用机械合金化方法制备了Fe100-xCox系超细粉末(x=15,35,50).对各样品进行了X-ray衍射谱的分析;用柯西分布公式计算了材料的晶粒尺寸,约为9~12nm;用最小二乘法计算了材料的晶格常数a;测量了不同成分样品的磁滞回线.研究发现,当x=15,35,5... 用机械合金化方法制备了Fe100-xCox系超细粉末(x=15,35,50).对各样品进行了X-ray衍射谱的分析;用柯西分布公式计算了材料的晶粒尺寸,约为9~12nm;用最小二乘法计算了材料的晶格常数a;测量了不同成分样品的磁滞回线.研究发现,当x=15,35,50时,材料均呈现了α-Fe的单相,并且样品有较低的矫顽力Hc和较高的饱和磁化强度Ms.用趋近饱和定律计算了样品的有效磁晶各向异性常数Ke和原子磁矩μ.研究表明,样品具有优良软磁材料的内禀性能. 展开更多
关键词 机械合金化 磁滞回线 纳米晶超细粉末 xray衍射谱
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厚钢管X射线图像中焊缝区域的检测 被引量:1
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作者 陈本智 方志宏 +3 位作者 夏勇 张灵 兰守忍 王利生 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2017年第4期131-138,共8页
由于传统焊缝区域检测算法难以准确提取模糊和对比度低的厚钢管焊缝区域,提出一种新的基于鲁棒PCA模型的焊缝区域检测算法,该算法能克服传统方法的不足,并能准确提取焊缝区域.首先,收集一序列X射线图像,并对其进行空域对齐及亮度归一化... 由于传统焊缝区域检测算法难以准确提取模糊和对比度低的厚钢管焊缝区域,提出一种新的基于鲁棒PCA模型的焊缝区域检测算法,该算法能克服传统方法的不足,并能准确提取焊缝区域.首先,收集一序列X射线图像,并对其进行空域对齐及亮度归一化预处理.其次,计算得到系列图像的背景图像,并将背景图像与待测试X射线图像张成一个观测矩阵.最后,使用鲁棒PCA算法对观测矩阵进行低秩与稀疏分解,测试图像中的不均匀强度及噪声被消除,焊缝区域被凸显出来,通过全局阈值可将焊缝区域较好地分割出来.实验结果表明,该算法能较大地消除厚钢管X射线图像中噪声及不均匀强度分布带来的干扰、同时增强模糊的焊缝边缘及对比度低的区域,相比传统焊缝区域检测算法,具有更高的检测灵敏度(0.952)和精度(0.989),能更好地将模糊和对比度低的焊缝区域完整检测出来. 展开更多
关键词 厚钢管 xray图像 焊缝区域 边缘检测 图像预处理
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Synthesis and Crystal Structure of Bis(tert-butyl-cyclopentadienyl)Erbium Ethoxide, (t-BuCp)_2ErOEt
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作者 罗云杰 姚英明 +1 位作者 沈琪 邢彦 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期374-377,共4页
The formation of ( t BuCp) 2ErOEt was discussed. Its single crystal structure was determined by X ray diffraction. The crystal is monoclinic, P 2(1)/ c space group, a =1.0191(2), b =1.6203(5), c ... The formation of ( t BuCp) 2ErOEt was discussed. Its single crystal structure was determined by X ray diffraction. The crystal is monoclinic, P 2(1)/ c space group, a =1.0191(2), b =1.6203(5), c =1.2118(3) nm, β =102.960(10)°, V =1.9500 (nm 3), Z =2, D c=1.566 mg·m -3 , R =0.0450, R w=0.1363. The complex is monomeric and solvent free in the solid state. The erbium ion is coordinated by two tert butyl cyclopentadienyl rings and one oxygen atom of ethoxy group to form a seven coordinated complex. 展开更多
关键词 rare earths organolanthanide tert butyl cyclopentadienyl ERBIUM ethoxide x ray crystal structure
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X射线衍射法定性分析陶瓷釉中的铅和镉相 被引量:1
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作者 黄燕纯 孙燕朋 +1 位作者 黄燕霞 童义平 《广州化工》 CAS 2010年第1期157-158,共2页
本研究运用X射线衍射技术对潮州市面陶瓷釉料的组成成分的物相样品进行了定性分析,结果显示,这些釉料样品中基本不含有毒的Pb、Cd氧化物等。
关键词 环保型陶瓷釉 物相 分析 xray衍射图
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Preparation and catalytic activity of CO-resistant catalyst core-shell Au@Pt/C for methanol oxidation 被引量:5
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作者 FENG Rongjuan LI Min LIU Jiaxiang 《Rare Metals》 SCIE EI CAS CSCD 2012年第5期451-456,共6页
Au@Pt core-shell nanoparticles were successfully synthesized by a successive reduction method and then assembled on Vulcan XC-72 carbon surface. Furthermore, its composition, morphology, structure, and activity toward... Au@Pt core-shell nanoparticles were successfully synthesized by a successive reduction method and then assembled on Vulcan XC-72 carbon surface. Furthermore, its composition, morphology, structure, and activity towards methanol oxidation were characterized by UV-vis spectrometry, transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV). Results reveal that Au@Pt/C catalyst has better activity towards methanol oxidation than the pure platinum prepared under the same conditions. When the atomic ratio of Au to Pt in the prepared Au@Pt/C catalyst is 1:2, this catalyst exhibits best electrocatalytic activity towards methanol oxidation in acidic media, and the peak current density on this catalyst is ~2.0 times higher than that on Pt/C catalyst. The better catalytic activity of Au@Pt/C results from its better resistance to toxic CO than Pt/C because the CO oxidation on Au@Pt/C is 60 mV more negative than the case on Pt/C. ? The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2012. 展开更多
关键词 Carbon Cobalt Cyclic voltammetry ELECTROCATALYSTS Gold METHANOL Nanoparticles Oxidation PHOTOELECTRONS Platinum Platinum alloys Synthesis (chemical) Transmission electron microscopy x ray diffraction x ray photoelectron spectroscopy
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