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91.
92.
Abhishek Kumar Subhalakshmi Nagarajan Ke Yang Robinson Anandakathir Jagdeep Singh Ramaswamy Nagarajan 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):963-966
A novel, one step and simple methodology for the fabrication of submicron scale silver patterns is demonstrated. The photosensitivity of an organic silver salt has been utilized for this purpose of fabrication. The silver-organometallic compound is converted to metallic silver selectively in the illuminated regions. Surface morphology was studied by scanning electron microscopy (SEM). Energy dispersion spectroscopy (EDS) shows the presence of silver in the developed film. X-ray photoelectron spectroscopy (XPS) confirms the formation of metallic silver. Feature sizes of the order of 200 nm have been achieved using this technique. 相似文献
93.
Soumitra Satapathi Sethumadhavan Ravichandran Ravi Mosurkal Subhalakshmi Nagarajan Lian Li Ramaswamy Nagarajan 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1061-1066
Resveratrol (3,5,4′ trihydroxy trans-stilbene) is a plant based phenolic compound. Enzymatic oligomerization of trans-resveratrol using horseradish peroxidase followed by characterization of the oligomer is presented. The oligomerization reaction was monitored using UV-Visible absorption and fluorescence spectroscopies. The oligomer exhibits strong two-photon-induced fluorescence. Computational modeling using spin-density calculations was performed to investigate the most probable reaction sites and the nature of products formed in the oligomerization process. 相似文献
94.
Sriram Ramaswamy 《Phase Transitions》2013,86(1-4):575-588
This is a brief review of the theory of topological defects in quasicrystals, within a densitywave picture. 相似文献
95.
96.
Ramaswamy Murugavel Prof. Subramaniam Kuppuswamy Nayanmoni Gogoi Ramamoorthy Boomishankar Dr. Alexander Steiner Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(3):994-1009
In contrast to the well‐known reaction of phosphonic acids RP(O)(OH)2 with divalent transition‐metal ions that yields layered metal phosphonates [RPO3M(H2O)]n, the 2,6‐diisopropylphenyl ester of phosphoric acid, dippH2, reacts with zinc acetate in methanol under ambient conditions to afford tetrameric zinc phosphate [(ArO)PO3Zn(MeOH)]4 ( 1 ). The coordinated methanol in 1 can be readily exchanged by stronger Lewis basic ligands at room temperature. This strategy opens up a new avenue for building double‐four‐ring (D4R) cubane‐based supramolecular assemblies through strong intercubane hydrogen‐bonding interactions. Seventeen pyridinic ligands have been used to synthesize as many D4R cubanes [(ArO)PO3Zn(L)]4 ( 2 – 18 ) from 1 . The ligands have been chosen in such a way that the majority of them contain an additional functional group that could be used for noncovalent synthesis of extended structures. When the ligand does not contain any other hydrogen‐bonding donor–acceptor sites (e.g., 2,4,6‐trimethylpyridine (collidine)), zero‐dimensional D4R cubanes have been obtained. The use of pyridine, lutidine, 2‐aminopyridine, and 2,6‐diaminopyridine, however, results in the formation of linear or zigzag one‐dimensional assemblies of D4R cubanes through strong intermolecular C? H???O or N? H???O interactions. Construction of two‐dimensional assemblies of zinc phosphates has been achieved by employing 2‐hydroxypyridine or 2‐methylimidazole as the exo‐cubane ligand on zinc centers. The introduction of an alcohol side chain on the pyridinic ligand in such a way that the ? CH2OH group cannot participate in intracubane hydrogen bonding (e.g., pyridine‐3‐methanol, pyridine‐4‐methanol, and 3,5‐dimethylpyrazole‐N‐ethanol) leads to the facile noncovalent synthesis of three‐dimensional framework structures. Apart from being useful as building blocks for noncovalent synthesis of zeolite‐like materials, compounds 1 – 18 can also be thermolyzed at approximately 500 °C to yield high‐purity zinc pyrophosphate (Zn2P2O7) ceramic material. 相似文献
97.
Cairncross RA Becker JG Ramaswamy S O'Connor R 《Applied biochemistry and biotechnology》2006,131(1-3):774-785
Management of moisture penetration and hydrolytic degradation of polylactide (PLA) is extremely important during the manufacturing, shipping, storage, and end-use of PLA products. Moisture transport, crystallization, and degradation, in PLA have been measured through a variety of experimental techniques including size-exclusion chromatography, differential scanning calorimetry, and X-ray diffraction. Quartz crystal microbalance and dynamic vapor sorption experiments have also been used to measure moisture sorption isotherms in PLA films with varying crystallinity. A surprising result is that, within the accuracy of the experiments, crystalline and amorphous PLA films exhibit identical sorption isotherms. 相似文献
98.
Copper(II) perchlorate and (PhCONH)P(O)(OH)2 (H2bpa) react in methanol to yield [Cu(Hbpa)2]n, a novel layered solid that displays several interesting features. Unlike the previously reported copper phosphonates, a rare hexacoordination around the metal is observed in the title compound because of the amide C=O coordination to Cu in addition to the phosphoramidate P-O coordination. The six-membered chelate rings present in the title compound are made up of five different elements (Cu, P, C, N, and O). 相似文献
99.
K. Murugavel S. Amirthaganesan R. T. Sabapathy Mohan 《Chemistry of Heterocyclic Compounds》2010,46(3):302-306
A new series of t-4-aryl-3,c-6-dihydroxy-6-methyl-4,5,6,7-tetrahydro-1H-indazole-r-5-carboxylic acid isopropyl esters has
been synthesized by adopting a conventional method from cyclic β-keto esters. 1H, 13C NMR, and IR spectra for all the compounds were investigated. HMBC, HSQC, COSY, and NOESY spectra of the representative compounds
were studied. The stereochemistry of a six-membered ring of the fused indazoles resembled that of keto esters. From the HMBC
correlations the indazole structure was confirmed as 1H-indazole. 相似文献
100.
R. P. Tripathi H. C. Verma S. Chandrasekhar S. Ramaswamy 《Hyperfine Interactions》2008,186(1-3):153-160
The paper describes part of the study carried out on the iron bearing phases of china clays collected from different china clay reserves of the country. Chemical assays of the clays as well as the “panned” impurities were determined by standard methods and the rational mineral data was calculated from the composition. XRD and thermal analysis also were carried out to get the mineralogy of the samples. Mössbauer spectral studies were conducted on the iron rich phases separated from the clays by “panning” to get information on the different iron minerals present in these clays. It was observed that Mössbauer spectra of the impurities from the low iron containing clays were qualitatively much different from those of the impurities from the high iron containing clays. 相似文献