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111.
Gold nanoparticles were encapsulated in sol-gel matrices with different amine cross-linker molecules in order to determine the cross-linker influence on nanoparticle agglomeration behaviour during encapsulation. The role of a stabilizing surfactant (SDS) was also investigated. The NP aggregate sizes were tracked using the UV surface plasmon resonance band (SPR), which red-shifts with increased particle size. It was found that use of long carbon chain cross-linkers such as 1,4-diaminobutane resulted in large Au NP aggregates, compared to short-chain analogs such as 1,2-diaminoethane, with which almost no agglomeration was observed. The SPR splitting pattern observed in samples with nanoparticle agglomeration is consistent with formation of nanodimensional objects with major and minor axes similar to nanowires during encapsulation within the cross-linked sol-gel material. The cross-linkers diethylenetriamine and triethylenetetraamine containing both terminal and internal amines demonstrated nanoparticle stabilization beyond that observed for similar sized diamine cross-linkers. This is ascribed to the multiple cross-linking sites available on these polyamines and the resulting reduction in matrix void volume. 相似文献
112.
Removal of lead(II) from aqueous solution with amino-functionalized nanoscale zero-valent iron 总被引:2,自引:0,他引:2
An effective adsorbent for removal of Pb(II) in aqueous solution was synthesized by reaction of nanoscale zero-valent iron
(NZVI) and 3-aminopropyltriethoxysilane (APS). The material was characterized using transmission electron microscopy (TEM),
infrared spectroscopy (IR) and a thermogravimetric analyzer (TGA). The amino-coated NZVI rapidly removed Pb(II) from aqueous
solution and was easily separated by an external magnetic field. The Freundlich equation was used for investigating the adsorption
process of APS-NZVI. Compared to untreated NZVI, the APS-coated NZVI exhibited stronger adsorption affinity and better adsorption
performance. Therefore, APS-NZVI may be a suitable material for heavy metal remediation and has potential industrial applications.
相似文献
113.
纳米零价铁(nZVI)作为一种高效还原性修复材料被广泛应用于多种污染物的去除,但易团聚、易被氧化失活的缺陷使其应用受到局限。近年来,研究者们通过将nZVI负载在多孔生物炭(BC)上来改善其本身缺陷,以期提高其应用潜力。本文综述了近年来nZVI/BC的制备方法及优缺点,总结分析了nZVI/BC对水体、土壤和沉积物中多种有机和无机污染物的去除效果和机理。同时综述了不同老化方法对nZVI/BC稳定性和反应活性的影响。在此基础上,在改进nZVI/BC制备技术、应用范围的拓展、潜在的生态和健康风险、探索老化过程和老化机制等方面进行了展望,旨在为nZVI/BC的理论研究和工程实践提供借鉴和参考。 相似文献
114.
Horng‐Jyh Harn Yi‐Lin Chen Po‐Cheng Lin Yeung‐Leung Cheng Shin‐Chun Lee Tzyy‐Wen Chiou Hsueh‐Hui Yang 《中国化学会会志》2010,57(2):180-188
To explore the potential tumor markers for lung adenocarcinoma, two‐dimensional gel electrophoresis (2DE) coupled with nano‐LC/MS/MS was used to analyze the differentially expressed proteins in 10 surgical resected lung adenocarcinoma tissues. 16 proteins were significantly different between the cancer tissue and adjacent normal tissue. Galectin‐1, peroxiredoxin II (Prx II), proapolipoprotein, glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), aldolase A, enolase 1, neuropolypeptide h3, Prx V, cyclophilin A, vimentin, protein disulfide isomerase (PDI), tropomyosin 3 (TPM 3), glutathione S‐transferase Pi (GST‐Pi), manganese superoxide dismutase (MnSOD), and cofilin 1 were up‐regulated in the cancer tissue. On the other hand, profilin was down‐regulated in the cancer tissue. Among these proteins, six proteins were validated by Western blot analysis. The identified proteins contributing to the spectrum of cancer progression may be used as potential diagnostic biomarkers for lung adenocarcinomas. 相似文献
115.
A mild template-free mixed solution medium with the assistant of microwave method was successfully established to synthesize well-aligned CuO nanostructures. By varying process parameters such as the volume ratio of the mixed solution, different kinds of architectural structures can be controllably synthesized in large quantities. On the basis of the results, it is found that the polarity of the solution plays the key role in controlling the growth of the CuO crystal. The as-prepared CuO products were characterized using diverse techniques including X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The gas sensor property investigation shows that the sensitivities to ethanol of the as-prepared CuO nanostructures are higher than those of normal CuO nanoparticles. 相似文献
116.
H. Ohtsuka K. Hojou H. Maeta H. Otsu H. Sugai H. Yamamoto 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,16(1):309-311
We investigated defect formation within nanostructured materials using a transmission electron microscope (TEM) and ion accelerators.
Controlling diffusion coefficient of the defects we have first observed changes in pattern of defect clusters, namely, the
diffusion-limited reaction of defects in nanocrystals.
Received 30 November 2000 相似文献
117.
A neat and efficient method for controllable and reproducible synthesis of coral-shaped matrix containing abundant nanoscale reaction pits on micrometer-size zerovalent iron powder is described with the study of etching capability of dilute hydrochloric, sulfuric, and nitric acids with concentration ranges from 1 N to 6 N. Characterizations of surface morphology show that the specific surface area of this matrix increases up to 170 times that of the untreated iron powder, and that the reduction efficiency of a PCB congener in subcritical water is enhanced fivefold from 18% for the untreated iron to 92% for that with 170 times its surface area. The nanoscale pits may be a basis for enhancement of reaction cross-section via restriction of molecule mobility in the pits. 相似文献
118.
M. Iwamoto K. Kuroda V. Zaporojtchenko S. Hayashi F. Faupel 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):365-367
Recently, production methods of metal nanoparticles have
been investigated extensively, not only for a research use in
laboratory, but also for an industrial use. However, it is
difficult to obtain metal nanoparticles in high amounts and
concentrations with simple methods. In this study, a gold
nanoparticle-polymer composite was prepared with a simple
procedure using a gold salt and a melted polymer. The composite,
which is in a wax state at room temperature, was highly soluble
in water and lower alcohols, moreover the composite was melted
at about 50
°C. 相似文献
119.
P.A. Orellana M.L. Ladrn de Guevara F. Domínguez-Adame 《Physica E: Low-dimensional Systems and Nanostructures》2005,25(4):384-389
A system of arrays of nanowires side-coupled to a quantum wire is studied. Transport through the quantum wire is investigated by using a noninteracting Anderson tunneling Hamiltonian. An analytical expression of the conductance at zero temperature is given, showing a band with alternating forbidden and allowed minibands due to the discrete structure of the nanowires. A generalization of the odd–even parity symmetry is found in this system, whose conductance exhibits a forbidden miniband in the center of the band for an odd number of sites in the nanowires, while shows an allowed band for an even number. 相似文献
120.
K. Akamatsu K. Nakahashi S. Ikeda H. Nawafune 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):377-380
Formation and structure of composite layer consisting of
polyimide films containing Ni nanoparticles were investigated.
The preparation method relies on KOH treatment on polyimide film
to form carboxyl acid groups and adsorption of Ni ions by ion
exchange followed by hydrogen reduction. The amount of Ni ions
adsorbed in polyimide films were found to be systematically
controlled by changing initial KOH concentration, subsequent ion
exchange time, pH and temperature. Cross-sectional TEM
observation revealed that Ni nanoparticles with 3-5 nm in
diameter were homogeneously dispersed in the surface modified
polyimide layer after heat treatment above 250
°C in H2
atmosphere. The size and distribution of the Ni nanoparticles
were strongly dependent on the heat treatment temperature,
indicating that this method allows microstructural tuning of
metal/polymer nanocomposites. 相似文献