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1.
Lu Xiao-nan Deng Fu-min Chen Xiao-hua Zhang Xiao-bin Wang Miao Li Wen-zhu 《浙江大学学报(A卷英文版)》2001,2(4):372-375
Bundles of pure carbon nanofibers were prepared by catalytic decomposition of acetylene on foam Ni. The morphological and
structural characteristics of the carbon nanostructures, in the as-prepared state, were analyzed by scanning electron microscopy
(SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HTEM). A special conformation
of carbon nanofibers composed of segmented structures was found among the products by both SEM and TEM observations. Further
HTEM examination indicated that the segments were stacked with well ordered graphite platelets arranged perpendicular to the
axis of the filaments.
Project supported by NSFC(Grant Nos 107202 n 19920 and 59872030) 相似文献
2.
TiO2 fibers were prepared via alternatively introducing water vapor and Ti precursor carried by Ne to an APCVD (chemical vapor deposition under atmospheric pressure) reactor at <200 ℃. Activated carbon fibers (ACFs) were used as templates for deposition and later removed by calcinations. The obtained catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brtmauer, Emmett and Teller (BET) and X-ray diffraction (XRD) analysisThe pores within TiO2 fibers included micro-range and meso-range, e.g., 7 nm, and the specific surface areas for TiO2 fibers were 141 m2/g and 148 m2/g for samples deposited at 100 ℃ and 200 ℃ (using ACF1700 as template), respectively. The deposition temperature significantly influenced TiO2 morphology. The special advantages of this technique for preparing porous nano-material include no consumption of organic solvent in the process and easy control of deposition conditions and speeds. 相似文献
3.
以具有Keggin结构硅钨酸为光催化还原剂,用光致还原Cr2O72-的方法制备了磷酸铬纳米粉体,Cr2O72-的还原过程用紫外-可见光谱进行监测。通过红外光谱（FT-IR）、X射线衍射（XRD）、扫描电镜（SEM）和透射电镜（TEM）分析表明所制产物为无定形磷酸铬,具有较规则的球形结构,平均粒径约为500nm。其合成机理是：在紫外光的照射下,当存在有机化合物时,形成了还原态的硅钨酸,还原态的硅钨酸将Cr（VI）还原为Cr（Ⅲ）,与体系中的PO43-结合生成磷酸铬,由于硅钨酸与磷酸铬之间存在结合力,硅钨酸对磷酸铬纳米颗粒的形成又起到了模板的作用。 相似文献
4.
采用沉积沉淀法制备了四氧化三铁负载磷酸银（Ag3PO4/Fe3O4）可见光磁性催化剂,利用透射电子显微镜（TEM）、扫描电子显微镜（SEM）对催化剂的微观形貌进行了表征。用甲基橙的光催化降解评价了不同负载量的Ag3PO4/Fe3O4复合催化剂的光催化性能。结果表明：当Ag3PO4负载量为50%时光降解效果最好,在模拟太阳光下,辐照80 min后的降解率可达到90%以上。 相似文献
5.
TiO2 fibers were prepared via alternatively introducing water vapor and Ti precursor carried by N2 to an APCVD （chemical vapor deposition under atmospheric pressure） reactor at ≤200 ℃. Activated carbon fibers （ACFs） were used as templates for deposition and later removed by calcinations. The obtained catalysts were characterized by scanning electron micros- copy （SEM）, transmission electron microscopy （TEM）, Brunauer, Emmett and Teller （BET） and X-ray diffraction （XRD） analysis The pores within TiO2 fibers included micro-range and meso-range, e.g., 7 nm, and the specific surface areas for TiO2 fibers were 141 m^2/g and 148 m^2/g for samples deposited at 100 ℃ and 200℃ （using ACFI700 as template）, respectively. The deposition temperature significantly influenced TiO2 morphology. The special advantages of this technique for preparing porous nano-material include no consumption of organic solvent in the process and easy control of deposition conditions and speeds. 相似文献
6.
张丁非 《重庆大学学报(英文版)》2004,3(2):12-15
IntroductionFe-C-Si-Mnalloyisamaterialusedforcommonbladesinhydroelectricgenerators.Itscurrentchemicalcompositionintermsofmassfractionwisasfollows:w(C)withintherangefrom0.17%to0.25%,w(Si)0.40%to0.8%,w(Mn)1.2%to1.6%,w(S)≤0.045%andw(P)≤0.045%.Thebladeserviceconditionrequiresgoodstrength,ductilityandwearresistance.AnormalprocessingandheattreatingprocedureofFe-C-Si-Mnalloybladesincludesinsequence:casting,920°Cnormalizing,600°Ctempering,andwelding.Thevolumeofabladeissohugethatitscentralare… 相似文献
7.
为了获得高负载、单分散的Pt／DCNTs异质结构,提出一种单步微波加热多元醇的方法．分别利用透射电子显微镜（TEM）和X射线衍射仪（XRD）表征了Pt／DCNT异质结构的形貌及成分．同时样品的拉曼光谱和傅里叶变换红外光谱（FTIR）表明：在微波处理下的双壁碳纳米管表面上有大量的缺陷或功能团产生,而它们的产生是Pt纳米粒子沿着双壁碳纳米管骨架成核与生长的关键因素． 相似文献
8.
以N a2SeSO3和Zn(A c)2.2H2O为源材料,通过微波辐射加热合成了ZnSe半导体纳米粒子,并用XRD和TEM进行了表征. 相似文献
9.
通过改变反先驱体中氯金酸含量,用水热法实现不同数量金纳米颗粒在活性炭表面的负载。采用透射电子显微镜（TEM）、红外光谱分析仪（IR）、同步热分析仪（TG）、比表面及孔径分析仪以及紫外可见吸收光谱（UV/Vis）对所得材料的形貌、组成和结构进行表征,并对其吸附性能进行研究。结果表明:采用水热法可实现不同数量金纳米颗粒在活性炭表面的均匀负载。负载金纳米颗粒在对活性炭组成影响不大的情况下能有效提升活性炭的热稳定性。随着负载量的增加,金纳米颗粒附着在活性炭的孔洞上引起比表面积和孔隙率逐渐减小。将活性炭负载金纳米颗粒的复合物对苯酚进行吸附处理,通过调整负载金纳米颗粒的数量可对活性炭吸附性能进行有效调控。 相似文献
10.
以SnCl4和TAA为Sn源和S源，在盐酸溶液中通过微波辐射加热合成了SnS2半导体纳米粒子，并用XRD、TEM进行了表征。 相似文献
11.
为减缓由于碳纤维与碳化硅基体热膨胀系数差异导致的微裂纹的产生,同时采用了C、SiC纤维作为增强体,通过有机前驱体浸渍裂解法(PIP)制备了(C-SiC)f/SiC复合材料,并通过扫描电子显微镜对复合材料的显微结构进行了分析,研究了复合材料中纤维排布方式以及基体相组成。研究发现,采用扫描电子显微镜的方法能够清晰地分辨出复合材料中各相的存在形式。从复合材料抛光面分析可以发现,在纤维束交错处存在束间基体聚集区域。复合材料基体主要由具有不同衬度的两相组成,分别是由含纳米SiC粉体浆料裂解产物和有机聚合物前驱体(PCS)裂解产物。PCS裂解产物主要呈带状,分布在浆料裂解过程中形成的裂纹和微孔中。 相似文献
12.
利用等离子体增强热丝化学气相沉积制备了碳纳米管，并用扫描电子显微镜和透射电子显微镜对生长的碳纳米管进行了表征。发现用CH4和H2制备的是空芯碳纳米管，而在反应气体中加入NH3后，生长的碳纳米管是竹节型结构的碳纳米管，表明氮在碳纳米管的结构变化过程中起到了重要的作用。根据氮对碳在催化剂中的扩散影响，分析了氮在碳纳米管结构发生变化过程中的作用。 相似文献
13.
在液相中依靠超声粉碎和剪切搅拌相结合的方法成功制备了Sn-Cd合金纳米微粒,并利用透射电子显微镜（TEM）、X-射线粉末衍射（XRD）、热分析（TG-DTA）等手段对合金纳米微粒的形貌和结构进行了表征,同时对合金纳米微粒用作润滑油添加剂的摩擦学性能进行了探讨. 相似文献
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15.
１ Ｉｎｔｒｏｄｕｃｔｉｏｎ Ｔｈｅｓｍａｌｌｓｉｚｅ（ｄｉａｍｅｔｅｒ＜１００ｎｍ）ｏｆｕｌｔｒａｆｉｎｅｐａｒｔｉｃｌｅｓｅｎｄｏｗｓｔｈｅｍｗｉｔｈｕｎｕｓｕａｌｓｔｒｕｃｔｕｒｅ,ｅｌｅｃｔｒｏｎｉｃ,ｏｐｔｉｃａｌ,ｍａｇｎｅｔｉｃａｎｄｃｈｅｍｉｃａｌｐｒｏｐｅｒｔｉｅｓ,ｌｅａｄｉｎｇｔｏｍａｎｙｉｍｐｏｒｔａｎｔａｐｐｌｉｃａｔｉｏｎｓｓｕｃｈａｓｃａｔａｌｙｓｔｓ,ｅｌｅｃｔｒｏｏｐｔｉｃａｌｄｅｖｉｃｅｓａｎｄｆｉｎｅｃｅｒａｍｉｃｓ［１］．Ａｓｏｎｅｏｆｓｐｅｃｉａｌｆ… 相似文献
16.
周少敏 《湖南科技学院学报》2004,25(6):53-57
作者采用Zn+Cd粉,制得了大量阵列Cd掺杂ZnO纳米梳子.这些纳米梳子通过X-射线衍射仪(XRD)、X-射线光电子能谱仪(XPS)、透射电子显微镜(TEM)、X-射线能量损失谱仪(EDS)、选区电子衍射仪(SAED)及高分辨透射电子显微镜(HRTEM)来分析其形貌和宏、微观结构.结果显示这些纳米梳子的臂直径为15-50
nm、臂长为400nm,它们都有单晶的结构及相应的生长机制为传统的气固生长机制. 相似文献
17.
席彩萍 《渭南师范学院学报》2012,(6):37-39
采用等离子体增强化学气相沉积技术,以C2H2、H2和N2为反应气体,制备出碳纳米管薄膜．利用扫描电镜和拉曼光谱仪对其进行表征．结果表明：气体流量大小对碳纳米管薄膜的生长起着重要作用,获得定向性良好、分布均匀、密度适中的碳纳米管的合适比例是C2H2：H2：N2=30：30：10（seem）． 相似文献
18.
作者采用Zn+Cd粉,制得了大量阵列Cd掺杂ZnO纳米梳子。这些纳米梳子通过X-射线衍射仪(XRD)、X-射线光电子能谱仪(XPS)、透射电子显微镜(TEM)、X-射线能量损失谱仪(EDS)、选区电子衍射仪(SAED)及高分辨透射电子显微镜(HRTEM)来分析其形貌和宏、微观结构。结果显示这些纳米梳子的臂直径为15-50 nm、臂长为400 nm,它们都有单晶的结构及相应的生长机制为传统的气固生长机制。 相似文献
19.
A commercial AA2618 alloy was treated through melt spinning at rotating speeds of 20 and 40 m·s−1. The as-melt spun ribbons were characterized by a combination of optical microscopy (OPM), scanning electron microscopy (SEM),
transmission electron microscopy (TEM) and X-ray diffraction (XRD). The microstructural evolution of the ribbons in a continuous
heating process was investigated, and the microhardness was also measured under different conditions. It was found that Al
x
FeNi is prone to precipitate in AA2618 alloy due to the minimal solubility of iron and nickel. Fine Al
x
FeNi particles appeared along the grain boundaries at the chilling sides of as-melt spun ribbons, and at both the grain boundaries
and in the interior of grains at the free sides. On continuous heating Al
x
FeNi precipitated steadily and uniformly throughout the matrix until melting. The microhardness of as-melt spun ribbons decreased
significantly from the chilling surfaces to free surfaces. Precipitation of Al
x
FeNi lowered the hardness of the alloy.
Project supported by Special Research Foundation of High-Education Ph. D. Subjects, Education Ministry of P. R. China. 相似文献
20.
ZnS∶Cu纳米微粒的制备及其光学性能 总被引：1，自引：0，他引：1
利用微乳液法制备出ZnS∶Cu纳米微粒 .透射电子显微镜 (TEM )和动态光散射 (DLS)测试结果表明 ,所得微粒粒径为 2～ 8nm .XRD结果表明 ,ZnS∶Cu纳米微粒为立方晶型结构 ,与体材料ZnS的晶型结构一致 ;在紫外吸收光谱中 ,ZnS∶Cu纳米微粒吸收峰蓝移 .发射光谱表明ZnS∶Cu纳米微粒产生一个位于 482nm的绿色发射带 相似文献