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251.
合成了一种新型的具有单晶结构的α-Fe2O3纳米晶(NFO-1).在我们的合成方法中,样品的形貌和结构在低反应浓度体系中运用无机盐和有机模板进行双重调控,同时用溶剂挥发诱导自组装(EISA)来加速反应和在不改变形貌结构的前提下获得高产率样品.所得α-Fe2O3纳米晶的形貌和结构对其表面修饰功能有明显的影响,NFO-1因其特殊的纺锤状形貌而与表面功能试剂(多巴胺)之间的化学作用有明显的增强.并且,本文所描述的合成方法同样适用于其他过渡金属氧化物纳米单晶的合成.我们预期,这种方法可为新型纳米材料的合成提供新的途径. 相似文献
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Youyi Sun Guizheng GuoBinhua Yang Wei CaiYe Tian Minghong HeYaqing Liu 《Physica B: Condensed Matter》2011,406(4):1013-1016
A new synthesis method of α-Fe2O3 nanoparticles was developed, in which the ferrous and ferric salts as well as polyaniline acted as the precursor and dispersant, respectively. From the investigation of X-ray diffraction and FT-IR spectra, the α-Fe2O3 nanoparticles can be directly prepared by the co-precipitation method without high-temperature calcining. Transmission electron microscope (TEM) and scanning electron microscope (SEM) observation revealed that the α-Fe2O3 nanoparticles had average diameters ranging from 30.0 to 75.0 nm. Compared with previous methods, this present method shows an easy processing and can be applied on the large-scale produce of α-Fe2O3 nanoparticles in one step. 相似文献
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Zadjia Atik 《Journal of Molecular Liquids》2011,163(2):89-92
The volumetric properties were evaluated from density data for the binary mixtures of (fluorobenzene + tert-butylmethyl ether), (α,α,α-trifluorotoluene + tert-butylmethyl ether), (tert-butylmethyl ether + ethanol), and the ternary mixtures of (fluorobenzene + tert-butylmethyl ether + ethanol) and (α,α,α-trifluorotoluene + tert-butylmethyl ether + ethanol). The observed densities were obtained by means of a vibrating-tube densimeter at the temperature 298.15 K and the pressure 101 kPa.The excess molar volumes of the ternary mixtures were estimated from binary solution data using several empirical equations with mean standard deviation less than 0.03 cm3·mol-1. Stable chemical cross-associations among the molecules forming the mixtures were revealed. 相似文献
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Maryam AbareshiSayyed Hashem Sajjadi Seyed Mojtaba Zebarjad Elaheh K. Goharshadi 《Journal of Molecular Liquids》2011,163(1):27-32
Magnetic nanofluids, ferrofluids, are a special category of smart nanomaterials, consisting of stable dispersion of magnetic nanoparticles in different fluids. In this study, magnetic nanoparticles of hematite, α-Fe2O3, were prepared by solvothermal method using Fe(NO3)3 as a starting material. The nanoparticles were characterized by X-ray diffraction (XRD) and transmission electronic microscope (TEM).To the best of our knowledge, this is the first research on the rheological properties of nanofluids of α-Fe2O3 nanoparticles and glycerol. The experimental results showed that the viscosity of α-Fe2O3-glycerol nanofluids increases with increasing the particle volume fraction and decreases with increasing temperature. Our results clearly showed that the α-Fe2O3-glycerol nanofluids are non-Newtonian shear-thinning and their shear viscosity depends strongly on temperature. The experimental data were compared with some theoretical models. The measured values of the effective viscosity of nanofluids are underestimated by the theoretical models. 相似文献
256.
The cross sections for (n,x) reactions with Ge isotopes were measured at (d–t) neutron energies around 14 MeV with the activation technique using metal discs of natural composition. Calculations of detector efficiency, incident neutron spectrum and correction factors were performed with the Monte Carlo technique (MCNP4C code). Cross sections data are presented for 70Ge(n,2n)69Ge, 74Ge(n,α)71mZn, 76Ge(n,2n)75(m + g)Ge, 70Ge(n,p)70Ga and 72Ge(n,2n)71gGe reactions. The cross section results for 72Ge(n,2n)71gGe reaction were reported for the first time. Some other cross sections were obtained with higher precision, including the 70Ge(n,p)70Ga reaction. Theoretical calculations of excitation functions were performed with the TALYS-1.0 code and compared with the experimental cross section values. Data were included in the EXFOR database. 相似文献
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