材料科学技术（英）
Ti-Fe nanoparticles with different concentrations were synthesized by gas condensation method. It is found that the size distribution of single phase nanoparticles obeys log normal distribution, and that of multiple phase nanoparticles is quite different. If it is assumed that the size distribution of each phase in multiple phase nanoparticles obeys log normal distribution as that of single phase particles, the calculated distribution curve is agreeable to the empirical curve. The inferences from the hypothesis are also supported by experimental results.
关键词:
particles
S.J. Yan
金属学报(英文版)
A practical technique to prepare transmission electron microscopy (TEM) thin foil containing powder particle was described and the data for the codeposition of two type particles with copper in the electroplating were presented. By depositing the particles which were distributed in CuSO4 electrolyte on cathode together with Cu2+ in electrodeposition bath, composite coating with suitable thickness could be formed. The thin coating was separated from the substrate and cut into a disc with diameter of 3mm for electropolishing. When the Cu matrix was thinned during electropolishing, the particles contained in the coating plate were also thinned to meet the suitable thickness for TEM observation. Various experimental results revealed that during electrodepositing the current density, pH-value of electrolyte and stirring mode all have significant effects on the distribution of particles in composite coating and the surface quality of the composite coating. The proper parameters used during electrodepositing to prepare TEM thin foil containing powder particle were discussed.
关键词:
electrodeposition
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Powder
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particles
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TEM
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t
Junchao TAO
,
Yue SHEN
,
Feng GU
,
Jinzhuan ZHU
,
Jiancheng ZHANG
材料科学技术（英）
Well-organized mesoporous titania particles and thin films were successfully synthesized by using tetrabutyl titanate as the inorganic precursor and triblock copolymer (Pluronic P123) as the template via evaporationinduced self-assembly process. The resulting materials were characterized by high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD). Fourier-transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) and atomic force microscopy (AFM). Macro shape of mesoporous titania would greatly influence the mesostructure of materials, and the probable reasons were also discussed.
关键词:
mesoporous titania
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null
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null
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null
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null
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null
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null
孟庆紫
,
樊曙先
,
何佳宝
,
孙玉
,
张健
,
张悦
环境化学
doi:10.7524/j.issn.0254-6108.2015.03.2014071601
为研究南京冬季大气颗粒物中PAHs来源情况，利用FA?3型气溶胶采样器从2007年11月20日到12月30日在南京郊区分昼夜采集气溶胶样品，并用GC?MS对16种优控PAHs浓度进行定量分析，采用PCA法对其来源进行解析。结果表明，南京冬季细颗粒物中PAHs浓度明显高于粗颗粒物中PAHs浓度，单种类PAH浓度表现出昼夜差异，日间低分子量PAHs含量高于夜间，而夜间高分子量PAHs浓度则相对较高；主成分分析对PAHs源解析结果表明，南京北郊大气颗粒物中PAHs主要来源为机动车尾气、燃煤源、焦化源、天然气燃烧和烹调源等，粗细颗粒物中PAHs排放源差异明显，细颗粒物部分表现出明显的昼夜差异，同时，外来源和不确定源占有较大比重。
关键词:
颗粒物
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PAHs
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风速风向
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主成分分析
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来源解析
刘方彪
,
王丹勇
,
陈以蔚
,
李树虎
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徐井利
,
魏化震
材料科学与工程学报
综述了颗粒增强、增韧环氧树脂基复合材料的制备方法,着重分析了影响该类复合材料力学性能的主要因素:颗粒的种类、分散性、几何尺度、结构与形貌以及含量等.最后,提出了颗粒增强、增韧环氧树脂基复合材料制备中面临的问题,并对今后研究动向进行了展望.
关键词:
颗粒
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环氧树脂
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制备方法
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力学性能
王美飞
,
杨丽莉
,
胡恩宇
色谱
doi:10.3724/SP.J.1123.2017.01023
建立了一种微波提取-高效液相色谱法测定大气颗粒物中多环芳烃的方法.吸附有颗粒物的超细玻璃纤维/石英纤维滤膜用正己烷/丙酮(1:1,v/v)混合溶剂经微波提取,提取液用弗罗里硅土柱净化,经浓缩定容后,采用液相色谱法-二极管阵列(PDA)-荧光双检测器测定.目标化合物在20.0~500 μg/L范围内线性良好,相关系数不小于0.9960.空白膜加标结果显示,目标化合物的回收率在56.3%~101%之间.该法已运用于南京市大气颗粒物中多环芳烃分布的调查研究.
关键词:
微波提取
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高效液相色谱法
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多环芳烃
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颗粒物
王锐
,
陈斌
工程热物理学报
本文发展了基于双向耦合的三维格子涡方法,采用涡方法模拟流场中的涡量变化及涡元运动,使用双势法求解速度场,采用拉格朗日方法跟踪颗粒相.利用该模型模拟了颗粒群的自由下落及下落过程引起的气相流动,模拟结果与实验吻合良好.结果显示空气相速度径向分布满足高斯分布,颗粒相流量对颗粒群的扩散影响不显著,而流量增大会引起颗粒速度的增大.
关键词:
格子涡方法
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颗粒群
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双向耦合
李小强
,
何涛
,
李勇
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曾定
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刘亮
,
古沸常
涂料工业
通过红外、质谱及核磁共振表征,确定了粉末涂料用聚酯树脂生产过程中产生的颗粒的主要成分为精对苯二甲酸,分析发现精对苯二甲酸未能充分参与反应、原材料及生产环境中带入的杂质都可能造成颗粒的产生.探讨了影响聚酯树脂中颗粒含量的因素,实验结果表明:较高的醇/酸比、更高效的催化剂、反应活性更高的单体及适宜的保温温度均有利于减少聚酯树脂中颗粒的含量.
关键词:
粉末涂料
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聚酯树脂
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颗粒
