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Cuprous oxide (Cu2O) nanorods doped with iron impurities have been synthesized by the polyol method using sodium dodecyl sulfate as the surfactant. The X-ray diffraction measurement reveals the pure phase of simple cubic Cu2O and the electron microscopy displays its one dimensional morphology. Ferromagnetism was observed at room temperature in the magnetic measurements of the doped samples while undoped sample exhibits only diamagnetism. Room temperature Mössbauer spectra for the samples exhibited only doublets but no sextet, which corresponds to the presence of paramagnetic iron sites. As magnetic moment contribution of the doped ions was insignificant for the observed magnetism, ferromagnetic property in the doped samples could have been originated from the defects as cation vacancies. Existence of the defects was supported by the room temperature photoluminescence spectra of the doped samples in reference to the undoped sample. 相似文献
114.
采用具有八面体形貌的氧化亚铜为模板,制备了聚苯胺/TiO2(PANI/TiO2)微/纳米球,TiO2纳米粒子很均匀地分散在聚苯胺中.研究了不同TiO2/苯胺(TiO2/ANI)摩尔比对PANI/TiO2复合物的结构、形貌和电学性能的影响.实验结果表明,随着TiO2/ANI摩尔比的增加,PANI/TiO2复合物的直径逐渐减小,当TiO2/ANI摩尔比为0.16时,复合物的平均直径为373nm,而当TiO2/ANI摩尔比增加到1.6时,复合物的平均直径降到80nm.PANI/TiO2复合微/纳米球的电导率随着TiO2/ANI摩尔比的增加先升高后降低,当TiO2/ANI摩尔比达到1.6时,电导率由10-4S/cm提高到100S/cm,达到最大值.产物的形貌和结构分别采用扫描电镜、透射电镜、红外吸收光谱和X-射线衍射等手段进行了表征. 相似文献
115.
This paper investigates the short-living absorption and the emission of CsI(Na) under a pulsed electron beam (Еe=0.25 MeV, t1/2=15 ns and W=0.003…0.16 J/cm2). The bands of singlet self-trapped excitons, as well as Na0 and Vk color centers have been detected in the transient absorption spectrum of CsI(Na). It has been found that the activator luminescence spectrum, peaking at 3.0 eV, fits a Gaussian (Em=3.0 eV and FWHM=0.44±0.02 eV at 80 K) and remains the same at different time delays within 10−8-10−3 s. The decay kinetics of the 3.0 eV emission has one nanosecond exponential component and two microsecond ones with time constants 1.0 and 3.0 μs, which remain unchanged within 78-150 K. It is concluded that the activator emission is due to the radiative annihilation of sodium-perturbed two halide excitons from the non-relaxed singlet state. The pathways of such excitons creation are discussed. 相似文献
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K. Rajender Reddy M. Venkateshwar C. Uma Maheswari P. Santhosh Kumar 《Tetrahedron letters》2010,51(16):2170-1420
An efficient synthesis of 1-iodoalkynes and iodophenols was easily achieved by employing simple KI and TBHP. The reaction does not involve the use of a metal and base combination. A variety of substituted alkynes and phenols were prepared with good to excellent yield. 相似文献
118.
Ion hydration has been studied for potassium iodide solutions with concentrations from 0 to 51 wt.% at temperatures from 288.15 to 308.15 K based on ultrasonic measurements and molar adiabatic compressibility data. For hydration complexes, structural characteristics have been determined. The structure of noncoordinated water plays a significant role even in concentrated solutions. An electrostatic ion field has a strong effect on the temperature dependence of the molar volume of hydration water. A method for the precise determination of the total solvation boundary is presented. 相似文献
119.
V. D. Dyachenko 《Chemistry of Heterocyclic Compounds》2005,41(9):1147-1150
3,5-Dicyano-2,6-diethylthiopyridine has been synthesized by the alkylation of cyanothioacetamide with ethyl iodide in DMF
and its molecular and crystal structures have been investigated.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1351–1354, September, 2005. 相似文献
120.
The quaternary chalcogeno halides AgHgSI, AgHgSBr and CuHgSI have been synthesized by annealing mixtures of silver (copper) halides and mercury sulphide. AgHgSI decomposes peritectoidally at 593±3 K and crystallizes in the orthohombic system with lattice constants ofa=772.3 (3),b=847.7 (3) andc=707.3 (3) pm. The phase diagram AgI-HgS resembles the AgI-Ag2S system closely. Contrary to the literature the only stable compound in this system is AgHgSI. The previously mentioned Ag2HgSI2 is metastable. The reported compound Ag2HgSBr2 could not be synthesized. The substitution of Hg2+ by Cd2+ in CuHgSI leads to a red phase Cu2Cd3S2I4 which crystallizes in the wurtzite type structure with lattice parameters ofa=424.7 (1) andc=695.2 (1) pm. 相似文献