20 research outputs found
Synthesis of one-dimensional Nanomaterials by anodic aluminum oxide templates
摘要一维纳米材料因其独特的电学、光学、磁学和化学性质,在化工、医药、生物、军事等重要领域均有广阔的应用前景,其制备和性能研究具有重要的意义。在一维纳米材料的制备方法中,多孔氧化铝模板由于具有典型的自组织结构、孔径大小一致、尺寸可控、排列规则等优点,成为制备一维纳米材料最常用且最有效的方法之一。本论文以多孔氧化铝为模板,结合溶胶-凝胶法,建立了在温和条件下制备纳米线和纳米管的一种简便方法,为制备新型功能性低维纳米材料提供了新的思路。主要包括以下几个方面的内容:1.在自制的装置中,采用电化学阳极氧化法制备了高度有序的多孔氧化铝有序阵列模板,并进行了TEM、SEM表征和荧光性质讨论。实验中简化了前期...Abstract A great deal of attention has been paid to one-dimensional nanomaterials due to their particular electrical, optical, magnetic and chemical properties, which induce their extensive potential applications in many fields, such as chemical industry, medicine. Hence researches on the preparation and properties of one dimensional nanomaterials are hot topics in material science. An...学位:理学硕士院系专业:化学化工学院化学系_无机化学学号:20032500
Determination of Molecular Mass of Insoluble Organic Compounds
介绍如何对基质辅助激光解吸飞行时间质谱仪(MAldI-TOf-MS)的样品靶进行加工改造,并针对不同类型的样品,如难溶有机物、金属配合物、高聚物、稠环芳烃或富勒烯、簇合物、挥发性差的液体等。采用不同的制样方式,提供了一种操作简便、通用性强的检测分子质量的表征方法,弥补了这些复杂化合物难以获得准确分子质量的不足,为解析这些化合物结构信息提供有力证据。Matrix assisted laser desorption ionization time of flight mass spectrometer( MALDI-Tof-MS) has very advantages such as less sample volume,fast detection,resistant to high salt content.Hence it has been widely used in biological molecules,polymers,organic compounds and so on,and generally is mixed with a certain proportion matrix after dissolving samples.In practice,some samples are extremely difficult to dissolve,or cannot find suitable solvent,so they cannot be used by the traditional method to obtain molecular weight on CGMS or LCMS.This paper presented to transform MALDI-Tof-MS sample target for different types of samples,such as insoluble organic compounds,metal complexes,polymers,polycyclic aromatic hydrocarbons or fullerene clusters.With different preparation methods,a convenient method of molecular detection was provided to obtain the accurate molecular mass.The method provides strong evidence for the analysis of the structure information
洪泽湖大型底栖动物群落结构及其与环境因子的关系
洪泽湖是我国第四大淡水湖,然而关于洪泽湖大型底栖动物的报道较少。为了研究洪泽湖大型底栖动物群落结构特征及其影响因子,在洪泽湖设置20个采样点,进行了为期1周年的季度调查(2010年5月-2011年2月)。共采集到大型底栖动物14种,寡毛类、摇蚊科幼虫和软体动物分别有5种(占总物种数的35.7%)、3种(21.4%)和6种(42.9%)。河蚬为第一优势种(优势度Y=0.18),其次分别为苏氏尾鳃蚓(0.09)、羽摇蚊(0.07)、霍甫水丝蚓(0.06)和铜锈环棱螺(0.06)。群落的平均密度和平均生物量分别为(45.45±7.38)个/m2和(52.43±12.04)g/m2,其中软体动物平均密度和平均生物量最高[(24.80±6.20)个/m2和(49.55±11.94)g/m2],摇蚊类次之[(13.76±2.87)个/m2和(2.28±0.71)g/m2],寡毛类最低[(6.96±2.41)个/m2和(0.60±0.18)g/m2]。全湖Shannon-Wiener、Margalef和Pielou指数分别为2.69、1.10和0.71,各指数季节差异不明显。冗余分析(RDA)结果共解释物种数据累计方差的35.0%;MonteCarlo检验表明,洪泽湖水体中硝酸盐氮、总氮和化学耗氧量是影响底栖动物群落分布最关键的环境因子(F=2.181~3.277,P<0.05)
Tailoring the optical property by a three-dimensional epitaxial heterostructure: A case of ZnO/SnO2
Epitaxial growth, as a best strategy to attain a heterostructure with a well-defined and clean interface, usually takes place on a planar substrate. In this paper, using a ZnO/SnO2 core-shell heterostructure as an example, we demonstrate the possibility of establishing a three-dimensional epitaxial interface between two materials with different crystal systems for the first time and show possible tailoring optical properties by building the heteroepitaxial crystal interface. The characterization results of element mapping, high-resolution transmission electron microscopy, and selected area electric diffraction reveal that the as-prepared ZnO/SnO2 heterostructure has a tetrapod-like ZnO core and a SnO2 shell with 15-30 nm, and their special epitaxial relation is (010)(SnO2)||(0110)(ZnO) and [100](SnO2)||[0001](ZnO). Such three-dimensional epitaxy between the ZnO core and SnO2 shell is quite different from the usual planar epitaxy or three-dimensional epitaxy between materials having the same crystal structure. A rational model of such complicated epitaxy has been proposed through investigating the certain structural comparability between the wurtzite ZnO and rutile SnO2 crystals. The as-prepared T-ZnO/SnO2 epitaxial heterostructure exhibits unique luminescence properties in contrast with individual tetrapod ZnO and SnO2 nanostructures, in which the epitaxial interface induces new luminescence properties. This result may inspire great interest in exploring other complicated epitaxy systems and their potential applications in laser, gas sensor, solar energy conversion, photo catalysis, and nanodevices in the future
Preparation and optical properties of ThO2 and Eu-doped ThO2 nanotubes by the sol-gel method combined with porous anodic aluminum oxide template
通讯作者地址: Xie, ZX (通讯作者), Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China
地址:
1. Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surfaces, Xiamen 361005, Peoples R China
2. Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, Xiamen 361005, Peoples R China
电子邮件地址: [email protected] this paper, we report the synthesis of thorium oxide and Eu-doped thorium oxide nanotubes for the first time using the sol-gel method in porous anodic aluminum oxide template. Transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were applied to characterize the morphology and structure of the as-prepared nanotubes. It has been demonstrated that Eu3+ ions were homogeneously doped into the ThO2 crystal lattice. The optical properties resulting from Eu-doped products were investigated by means of photoluminescence spectroscopy. Strong visible light emissions were observed at low doping concentration, and the luminescent intensity decreased at high doping concentration. The luminescent centers were concluded to be the Eu3+ ions in the cubic (O-h) sites rather than the C-3 upsilon sites, which accounted well for the decrease of luminescent intensity at high doping concentration
IR, FT-ICR-MS studies on (1 ' S, 6 ' S)-1-cyclopropyl-7-(2,8-diazabicyclo[430] non-8-yl)-6-fluoro-8-methoxy-4-oxo-1, 4-dihydroquinoline-3-carboxylic acid hydrochloride salt
The infrared spectra of (1'S, 6'S)-1-cyclopropyl-7-(2,8-diazabicyclo[4.3.0] non-8-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3-carboxylic acid hydrochloride salt (CLF-HCl) were studied and compared with free base. Their fragmentation pathways were investigated using tandem mass spectrometric (MS/MS) techniques on Fourier-transform ion cyclotron resonance spectrum, and many characteristic fragment ions were found. (C) 2013 Elsevier B.V. All rights reserved
IR, FT-ICR-MS studies on (1S, 6S)-1-cyclopropyl-7-(2,8- diazabicyclo[430] non-8-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3- carboxylic acid hydrochloride salt
The infrared spectra of (1′S, 6′S)-1-cyclopropyl-7-(2,8- diazabicyclo[4.3.0] non-8-yl)-6-fluoro-8-methoxy-4-oxo-1,4-dihydroquinoline-3- carboxylic acid hydrochloride salt (CLF-HCl) were studied and compared with free base. Their fragmentation pathways were investigated using tandem mass spectrometric (MS/MS) techniques on Fourier-transform ion cyclotron resonance spectrum, and many characteristic fragment ions were found. ? 2013 Elsevier B.V. All rights reserved
Application of MALDI-Tof-MS and FT-ICR-MS in Study on Schiff Base Nickel Complexes
本研究对基质辅助激光解吸电离飞行时间质谱(MAldI-TOf-MS)的原理和应用做了简要介绍,并概括了常用基质的应用特点和适用范围。通过基质的选择及测试条件的优化,分别对3种席夫碱镍配合物进行质谱分析,实验结果表明,[M+H]+峰的分子质量以及同位素丰度都与理论计算值十分吻合。采用此法不仅能准确地测定席夫碱镍配合物的分子质量,为席夫碱镍配合物结构的鉴定奠定基础,也是金属有机化合物分子质量测定的有效方法,是快速分析金属有机化合物的工具之一。为了进一步说明质谱在金属配合物测定中的可靠性,辅以傅里叶变换离子回旋共振质谱仪(fT-ICr-MS)进行确证。The principle and applications of matrix-assisted laser desorption ionization time of flight mass spectrometry(MALDI-Tof-MS) were briefly introduced.The characteristics and scope of the application of matrixes were summarized.Three Schiff base nickel complexes were respectively analyzed by MALDI-Tof-MS.The results showed that the molecular weight + peak and the isotopic abundance were very consistent with the theoretical value.By this method not only the molecular weight of Schiff base complexes was accurately determined,providing important assistance for the structural identification,but also it would be an effective and rapid tool for identification of metal organic complexes,and supplemented by Fourier transform ion cyclotron resonance mass spectrometer(FT-ICR-MS) for confirmation.国家自然科学基金(2077309820973136)资
Au-20 Nanocluster Protected by Hemilabile Phosphines
A novel phosphine-protected Au-20 nanocluster was isolated through the reduction of Au(PPhpy(2)) Cl by NaBH4 (PPhpy(2) = bis(2-pyridyl)-phenylphosphine). Its composition was determined to be [Au-20(PPhpy(2))(10)Cl-4]Cl-2, and single crystal X-ray structural analysis revealed that the Au-20 core can be viewed as being generated from the fusion of two Au-11 clusters via sharing two vertices. Optical absorption spectroscopy indicated this Au-20 has a large HOMO-LUMO gap (E-g approximate to 2.24 eV). This is the first example of a ligand-protected gold nanocluster with a core generated from incomplete icosahedral Au-11 building units.Natural Science Foundation of China [21125102, 20973135, 90922011, 21021061
Au20 nanocluster protected by hemilabile phosphines
A novel phosphine-protected Au20 nanocluster was isolated through the reduction of Au(PPhpy2)Cl by NaBH4 (PPhpy 2 = bis(2-pyridyl)-phenylphosphine). Its composition was determined to be [Au20(PPhpy2)10Cl4]Cl 2, and single crystal X-ray structural analysis revealed that the Au20 core can be viewed as being generated from the fusion of two Au11 clusters via sharing two vertices. Optical absorption spectroscopy indicated this Au20 has a large HOMO-LUMO gap (E g 2.24 eV). This is the first example of a ligand-protected gold nanocluster with a core generated from incomplete icosahedral Au11 building units. 漏 2012 American Chemical Society