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Summary Reduction of anhydrous FeCl3 in THF with sodium naphthalenide under a CO atmosphere at room temperature leads directly to Na2Fe(CO)4, which on reaction with alkyl bromides gives the corresponding aldehydes, ketones and carboxylic acids under appropriate conditions. 相似文献
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Phenol, an important bulk organic compound, has diverse applications encompassing both industry and society. Commercially, it is produced through energy intensive three-step cumene process operating at relatively low yield with the co-production of acetone. Several attempts were made for producing phenol through challenging one-step direct hydroxylation of benzene using different oxidants like O2, N2O and H2O2. Liquid phase hydroxylation of benzene using H2O2 found to be more attractive due to its low reaction temperature and environmentally friendly nature (as water is only formed as by-product). The hydroxylation reaction occurs through Fenton’s mechanism; however along with phenol several other products are also formed due to higher reactivity of phenol compared to benzene. Our research group has been working on this reaction for nearly a decade using layered double hydroxides (LDHs) and their derived forms as heterogeneous selective oxidation catalyst. Screening of different LDHs having different metal ions in the layers revealed the necessity of copper for hydroxylation in pyridine. Addition of co-bivalent metal ion along with copper was made in an endeavour to improve the activity that revealed the promising results for CuZnAl LDHs. Efforts were then made to shift from pyridine to environmentally benign solvent, water, for this reaction that showed reasonably good yields with very high selectivity of phenol. Addition of small amount of sulfolane as a co-solvent increased the selectivity for phenol further. The reusability difficulty faced while using as-synthesized LDHs was overcome when calcined LDHs were used. Structure–property-activity relationships were deduced to understand the results observed. The present review besides covering our work also provides the state-of-art on this reaction using different oxidants with emphasis on H2O2. 相似文献
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Antonyraj Arockiasamy Randall M. German Paul Wang Mark F. Horstemeyer Pavan Suri S. J. Park 《Journal of Thermal Analysis and Calorimetry》2010,100(1):361-366
Differential scanning calorimetry (DSC) is a powerful technique that measures the heat evolution from a sample under a controlled
condition and studies the phase transformation, precipitation, and dissolution activities. In this work, we investigated the
influence of admixed silicon and silicon carbide and the effect of different atmospheres on the heat flow properties and microstructure
of atomized Al6061 powder using DSC and scanning electron microscopy. The DSC analysis revealed the addition of silicon considerably
decreased the temperature of first endothermic peaks. With an increase in silicon content the enthalpy for the first endothermic
peak increased, whereas the second endothermic peak decreased. An endothermic peak, indicating the formation of AlN, was observed
for powders without the silicon addition, but was noticeably absent in the case of alloys with Si addition. The SiC addition
has no influence on changing the enthalpy of the systems we investigated. The reason for this behavior is analyzed and presented
in this article. 相似文献
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Antonyraj Arockiasamy Hossein Toghiani David Oglesby M. F. Horstemeyer J. L. Bouvard Roger L. King 《Journal of Thermal Analysis and Calorimetry》2013,111(1):535-542
The thermal decomposition behavior of styrene-butadiene rubber was studied using a system equipped with thermogravimetric analysis, differential thermal analysis, Fourier transform infrared spectroscopy, and mass spectroscopy. Two different experiments were conducted. From these experiments, thermogravimetric analysis results indicated a mass loss of 58 % in the temperature range of ~290–480 °C and a mass loss of 39 % in the temperature range beyond 600 °C. Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy confirmed the presence of oxides, even at 1,000 °C, accounting for the Zn, Mg, Al, Si, and Ca in the original sample. 相似文献
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Shivaramaiah Radha Churchil A. Antonyraj Prof. Dr. P. Vishnu Kamath Dr. Srinivasan Kannan 《无机化学与普通化学杂志》2010,636(15):2658-2664
Solid–solid inter‐polytype transformations are observed during the thermal dehydration of sulfate‐containing layered double hydroxides (LDHs). The metal hydroxide layer behaves as a “structural synthon” and the interconversion of polytypes of rhombohedral and hexagonal symmetries takes place by rigid translations of successive layers by (± 1/3, ± 2/3) relative to one another in the ab plane. These translations are selected among the many possible, as they preserve the coincidence of the symmetry elements of the individual layers and thereby conserve the threefold symmetry of the crystal across the inter‐polytype conversions. As a result, these transformations are enthalpically not expensive. These translations are facilitated at near ambient temperatures (30–60 °C) by the reversible dehydration of the LDH, which involves the deinsertion/insertion of water molecules within the restricted space of the interlayer region. 相似文献
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Arockiasamy S Krishnan IP Anandakrishnan N Seenivasan S Sambath A Venkatasubramani JP 《Applied biochemistry and biotechnology》2008,151(2-3):371-379
Plackett and Burman design criterion and central composite design were applied successfully for enhanced production of laccase by Coriolus versicolor NCIM 996 for the first time. Plackett and Burman design criterion was applied to screen the significance of ten nutrients on laccase production by C. versicolor NCIM 996. Out of the ten nutrients tested, starch, yeast extract, MnSO(4), MgSO(4) x 7H(2)O, and phenol were found to have significant effect on laccase production. A central composite design was applied to determine the optimum concentrations of the significant variables obtained from Plackett-Burman design. The optimized medium composition for production of laccase was (g/l): starch, 30.0; yeast extract, 4.53; MnSO(4), 0.002; MgSO(4) x 7H(2)O, 0.755; and phenol, 0.026, and the optimum laccase production was 6,590.26 (U/l), which was 7.6 times greater than the control. 相似文献
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Larry D. Merkle G. Alex Newburgh Nikolay Ter-Gabrielyan Arockiasamy Michael Mark Dubinskii 《Optics Communications》2008,281(23):5855-5861
Spectroscopic and laser properties of Yb3+ in ceramic Y2O3 have been studied at room and cryogenic temperatures. Laser performance is very substantially improved by cooling to liquid nitrogen temperature, primarily due to the great reduction in ground state absorption that permits laser operation on the much stronger 1030-nm emission line rather than the 1077-nm line. The 976-nm “zero line” is observed to become much weaker as the temperature is reduced. Several models for this behavior are considered, but none adequately explains this surprising result. Spectroscopy of Yb:Sc2O3 indicates that it is likely to be an even better cryogenic gain material, given samples of comparable optical quality. 相似文献
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Gopinath Samykannu Perumal Perumal Rahul Raina Arulandu Arockiasamy Narayanan Sundarabaalaji 《Crystallography Reports》2019,64(7):1108-1111
Crystallography Reports - Many pathogenic gram-negative bacteria including Salmonella typhi utilize type III secretion systems (T3SSs) to inject bacterial proteins into host cells and to initiate... 相似文献
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