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71.
Research on Chemical Intermediates - A new heterogeneous nanomagnetic catalyst bearing morpholine tags was synthesized and characterized. The formation of the nanomagnetic catalyst was fully...  相似文献   
72.
Russian Journal of Electrochemistry - In the acidic condition the oxygen reduction reaction (ORR) through the aluminum doped silicon nanocage (Al–Si78) is studied. The ORR reactions are...  相似文献   
73.
Nanocrystalline La0.73Sr0.27MnO3 perovskite oxides with an average particle size of 26 nm were synthesized using the sol-gel method. To make water based magnetic fluid, the obtained nanoparticles were coated by self-organized bilayer surfactant containing oleic acid and sodium dodecyl sulfate as inner and outer layer, respectively. The bare and coated nanoparticles were characterized by x-ray powder diffraction, Fourier transform infrared spectroscopy, thermogravimetry, and transmission electron microscopy analyses. Calorimetric analysis was used to determine the heat generation efficiency of the prepared magnetic fluid under various alternating magnetic fields. The obtained results revealed that the maximum temperature achieved by the nanoparticles is in the therapeutic temperature range which enables these materials to be used as self-controlled heating agents in magnetic hyperthermia therapy.  相似文献   
74.
A simple synthesis of highly functionalized 2,5-diaminofurans based pyrimidine derivatives from l-(carboxymefhyl)uracil via a multi-component reaction is described.The reactive 1:1 intermediate produced from the reaction of tert-butyl isocyanide and dialkyl acetylenedicarboxylates was trapped at room temperature by l-(carboxymethyl)uracil derivatives to yield polyfunctionalized furan rings in fairly good yields.  相似文献   
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76.
Meysam Bolgorian 《Physica A》2011,390(23-24):4514-4521
Studying the relation between corruption and economic factors and examining its consequences for economic development have attracted many economists and physicists in recent years. The purpose of this paper is to focus on the role of stock market development on corruption. Analyzing a data set of corruption and stock market development measures such as market capitalization and total value of share trading for 46 countries around the world for the period 2007–2009, we examine the dependence of the Corruption Perception Index (CPI) on stock market development. Our findings suggest that there exists a power-law dependence between corruption and stock market development. We also observe a negative relation between level of corruption and financial system improvement.  相似文献   
77.
The reactive 1:1 intermediate produced in the reaction between alkyl isocyanides and dialkyl acetylenedicarboxylates was trapped by uracil and its 5‐substituted derivatives to yield highly functionalized pyrimido[2,1‐b][1,3]oxazine derivatives in fairly good yields. J. Heterocyclic Chem.,(2011).  相似文献   
78.
Research on Chemical Intermediates - In this investigation, a new application of 1H-imidazol-3-ium tricyanomethanide catalyst was explored. The catalyst presented a robust catalytic applicability...  相似文献   
79.
In this work, a green, simple and highly efficient procedure for the synthesis of bis(indolyl)methanes is described. The condensation of indoles catalyzed by p-sulfonic acid calix[4]arene in water and under solvent-free conditions afford the title compounds in high yields and relatively short reaction times.  相似文献   
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