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β-Keto esters and acetyl acetone on condensation with glycosylated amino esters in the presence of IR-120 resin resulted in high yields of glycosyl enamino esters or ketones. The latter on cyclisation with NaH in toluene at reflux gave 6-glycosyl-5,6-dihydro-1H-pyridin-4-ones in fair to good yields. 相似文献
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Pyrazolopyrimidine and pyrimidopyrimidine derivatives have shown a wide range of biological activities such as acting as A1 adenosine receptors, kinase insert domain receptor (KDR), Rous sarcoma oncogene (Src), epidermal growth factor receptor (EGFR), antiproliferative, dihydrofolate reductase (DHFR), antimicrobial, antifungal, and lipid peroxidation. Because of this wide range of activities, we have synthesized pyrazolo[3,4‐d]pyrimidines and pyrimido[4,5‐d]pyrimidin‐4‐one derivatives. 相似文献
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Journal of Thermal Analysis and Calorimetry - In the present investigation, gene expression programming (GEP) is used to predict thermal conductivity of nanofluids consisting of $$\hbox {Al}_2\hbox... 相似文献
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JPC – Journal of Planar Chromatography – Modern TLC - Asensitive, selective, and precise high-performance thin-layer chromatography (HPTLC) method was developed for simultaneous... 相似文献
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Ligand bridged polymeric complexes of the type [M(apainh)(H2O)X] where, M=Mn(II), Co(II), Ni(II), Cu(II), and Zn(II); X=Cl2 or SO4; apainh=acetone p‐amino acetophenone isonicotinoyl hydrazone have been synthesized and characterized. The complexes are stable solids, insoluble in common organic solvents and are non‐electrolytes. Magnetic moments and electronic spectral studies suggest a spin‐free octahedral geometry for all Mn(II), Co(II), Ni(II), and Cu(II) complexes. IR spectra show tridentate nature of the ligand bonding through two >C?N and a >C?O groups. X‐ray powder diffraction parameters for some of the complexes correspond to orthorhombic and tetragonal crystal lattices. Thermal studies (TGA and DTA) of [Mn(apainh)(H2O)SO4] complex show multi‐step decomposition pattern of both an endothermic and exothermic nature. ESR data of Cu(II) chloride complex in solid state show an axial spectra, whereas, Cu(II) sulfate complex is isotropic in nature. The complexes show a significant antifungal activity against a number of pathogenic fungal species and antibacterial activity against Pseudomonas sp. and Clostridium sp. The metal complexes are more active than the ligand. 相似文献
7.
Diksha Chawla Noble Jacob H. V. Mohokar 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):29-32
For the optimal exploitation and management of coastal aquifers of Tamil Nadu, it is essential to evaluate the groundwater outflow into the sea also called as submarine groundwater discharge. In this study, radium isotopes (223,224Ra) were employed to understand the groundwater discharge in coastal areas of Cuddalore district, Tamil Nadu. Sea water samples (100 L) were collected from various locations of Cuddalore coast in October 2011 and passed through Mn-impregnated acrylic fiber columns. These acrylic columns were analyzed for 223,224Ra activities using radium delayed coincidence counter. The observed higher activities of 223,224Ra excess (0.02 ± 0.001–3.28 ± 0.16 and 64 ± 3–380 ± 19 mBq/100 L respectively) indicate that groundwater discharge occurs in this coastal region. 相似文献
8.
Emergence of the sub‐THz central peak at phase transitions in artificial BaTiO3/(Ba,Sr)TiO3 superlattices 下载免费PDF全文
Yu. A. Tikhonov A. G. Razumnaya V. I. Torgashev I. N. Zakharchenko Yu. I. Yuzyuk M. El Marssi N. Ortega A. Kumar R. S. Katiyar 《固体物理学:研究快报》2015,9(1):68-71
A prominent central peak in the sub‐THz frequency range was observed in the Raman spectra of BaTiO3/(Ba,Sr)TiO3 (BT/BST) superlattice grown on (001)MgO substrate. Both soft and central mode show an anomaly around 200 K and 280 K, which can be correlated with orthorhombic to monoclinic phase transition of BST and BT, respectively. The observed temperature dependence of the central mode enabled us to explain rather broad temperature dependence of the dielectric permittivity previously observed in BT/BST superlattices. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
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The conversion of CO2 to useful chemicals, especially to atom economical products, is the best approach to utilize an excess of CO2 present in the atmosphere. In this study, a metal‐organic framework (ZIF‐8) is integrated with nanocrystalline zirconosilicate zeolite to develop an integrated porous catalyst for CO2 insertion reactions. The catalyst exhibits excellent activity for the CO2 insertion reaction of epoxide to produce cyclic carbonate in neat condition without the addition of any co‐catalyst. The catalyst is stable and recyclable during the cyclic carbonate synthesis. Further, the catalyst also exhibits very good activity in another CO2 insertion reaction to produce quinazoline‐2,4(1H, 3H)‐dione. 相似文献