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Optical and Quantum Electronics - Nowadays, world is moving from conventional energy sources to non-conventional energy sources like solar energy, wind power, hydropower and those energy sources...  相似文献   
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An attempt has been made to prepare cobalt-doped lithium manganese oxide with three different concentrations by simple molten salt method to enhance the electrical property of Li4Mn5O12. Prepared samples were examined by XRD and SEM to identify its structure and morphology. Electrical properties were identified by impedance and conductivity analysis, and it was found that the material exhibits negative temperature coefficient (NTCR) property, i.e., semi-conducting nature. Among the various concentrations, 0.5 mol of Co-doped lithium manganese oxide has shown good conductivity of 3.1 × 10?5 S cm?1 at 433 K.  相似文献   
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Hydrogen-bonding interactions in DNA/RNA systems are a defining feature of double helical systems. They also play a critical role in stabilizing other higher-order structures, such as hairpin loops, and thus in the broadest sense can be considered as key requisites to the successful translation and replication of genetic information. This importance, coupled with the aesthetic appeal of nucleic acid base (nucleobase) hydrogen-bond interactions, has inspired the use of such motifs to stabilize a range of synthetic structures. This, in turn, has led to the formation of a number of novel ensembles. This tutorial review will discuss these structures, both from a synthetic perspective and in terms of their potential application in areas that include, but are not limited to, self-assembled macrocyclic and high-order ensemble synthesis, supramolecular polymer preparation, molecular cage construction, and energy and electron transfer modeling.  相似文献   
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A new non-covalent electron transfer model system, based on the use of cytidine-guanosine hydrogen bonding interactions, is described that incorporates a phthalocyanine photodonor and a C60 fullerene acceptor.  相似文献   
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The phosphetidine 2,4‐Di‐tert‐butyl‐3‐chloro‐1λ6‐thia‐2,4‐diaza‐3‐phosphetidine‐1,1‐dioxide, O2S (tBuN)2PCl, reacts with tetrasulfur tetranitride, S4N4, in benzene under reflux to afford the novel 4,6‐spirocycle in moderate yield. The deep‐blue crystals of the spirocycle are airstable and high melting in nature. The spiro phosphorus atom subtends a four‐membered PVSVIN2 ring which is saturated, and a six‐membered PVS N3 ring which is unsaturated. The single‐crystal X‐ray structure of this first example of the spirocycle reveals a planar PSN2 ring and a puckered PS2N3 ring and the molecule is symmetric in nature. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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Semicarbazone of dl-camphor (SdlC) crystals were grown using methanol as a solvent by slow evaporation solution growth technique at room temperature. Formation of the product and the presence of various functional groups present in the grown crystal have been identified using FTIR spectra. Single crystal XRD study was conducted to obtain the crystal structure and lattice parameters. The grown crystal was subjected to 1HNMR and 13CNMR spectral studies and TG-DTA in order to confirm its structure, purity, and stability, respectively. The optical transparency of the crystal was tested using UV–Vis–NIR spectroscopy. The nonlinear optical (NLO) property of the grown crystal was confirmed from the second harmonic generation (SHG) by Kurtz–Perry powder test.  相似文献   
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The dislodgable residues of methomyl from leaves and vegetables were determined by a single-step methanol extraction followed by reversed-phase HPLC. The residues on the bhendi vegetables and leaves were several times higher than on the brinjal vegetables and leaves. The pesticide, however, dissipates rapidly under the South Indian climatic conditions resulting in undetectable residues within three days of spraying.  相似文献   
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