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141.
R. Ramesh Babu N. Vijayan R. Gopalakrishnan P. Ramasamy 《Journal of Crystal Growth》2002,240(3-4):545-548
Single crystals of potential organic nonlinear optical materials of Benzaldehyde Semicarbazone (BSC) were grown by slow evaporation technique. The grown crystals were identified by X-ray diffraction method. The functional groups were identified from FT-IR spectrum. UV-visible and thermal gravimetric analyses were made. 相似文献
142.
143.
Uemura YJ Luke GM Sternlieb BJ Brewer JH Carolan JF Hardy WN Kadono R Kempton JR Kiefl RF Kreitzman SR Mulhern P Riseman TM Williams DL Yang BX Uchida S Takagi H Gopalakrishnan J Sleight AW Subramanian MA Chien CL Cieplak MZ Xiao G Lee VY Statt BW Stronach CE Kossler WJ Yu XH 《Physical review letters》1989,62(19):2317-2320
144.
A. Ramanujam P. V. Achuthan P. S. Dhami R. Kannan V. Gopalakrishnan V. P. Kansra R. H. Iyer K. Balu 《Journal of Radioanalytical and Nuclear Chemistry》2001,247(1):185-191
A generator system has been developed for the preparation of carrier-free 90Y from 90Sr present in the high level waste (HLW) of the Purex process by employing a supported liquid membrane (SLM) using 2-ethylhexyl-2-ethylhexyl phosphonic acid (KSM-17 equivalent to PC 88A) supported on a polytetrafluoro ethylene (PTFE) membrane. When uranium depleted Purex HLW at appropriate acidity is passed sequentially through octyl (phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) sorbed on chromosorb-102 (abbreviated as CAC) and Zeolite AR1 (synthetic mordenite) columns, all the trivalent, tetravalent and hexavalent metal ions and monovalent 137Cs ions are sorbed. After adjusting to pH 2 with NaOH the resulting effluent is used as feed in a single stage membrane cell partitioned with a PTFE membrane impregnated with KSM-17 and having a feed and receiver compartment with 5.0 ml capacity each. The receiver compartment was filled with a 0.5M HNO3 or 0.5M HCl stripping solution. 90Y alone is preferentially transported across the membrane leaving behind all the impurities viz. 90Sr, 125Sb, 106Ru, 106Rh, etc. in the feed compartment. This technique can yield 90Y in mCi levels in a pure and carrier-free form for medical applications. The feed can be reused repeatedly after allowing for 90Y buildup. 相似文献
145.
T. Kanagasekaran M. Gunasekaran P. Srinivasan D. Jayaraman R. Gopalakrishnan P. Ramasamy 《Crystal Research and Technology》2005,40(12):1128-1133
Single crystals of m‐Nitroaniline (mNA) were grown by slow cooling solution growth technique. Induction period, interfacial energy and metastable zonewidth have been evaluated. The solubility of mNA has been estimated at different temperatures in acetone and ethanol. Interfacial energy has been estimated using the experimentally determined induction period values. It is observed that the nucleation rate increases with the increase of supersaturation. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
146.
147.
Shivaraman Ramaswamy C. Gopalakrishnan N. Satyavijaya Kumar Angeline Littleflower M. Ponnavaikko 《Applied Physics A: Materials Science & Processing》2010,98(3):481-485
Two-dimensional nickel nanodots were prepared using a simple polymer based lithography process on silicon substrates. The
nanoporous polysulfone membranes were fabricated using a phase inversion polymerization process. Nickel nanodots were then
grown using the polysulfone membrane as a mask. The structures were written by depositing a certain thickness of nickel using
electron beam evaporation. After lift off, the structural properties of the samples were studied using atomic force microscopy
and grazing incidence X-ray diffractometry. The dots were found to have diameters in the range of 75–120 nm and heights of
3–5 nm. The magnetization and magnetic domain arrangement of the Ni nanodots were analyzed using vibrating sample magnetometer
and magnetic force microscopy respectively. The nanodots were found to exhibit excellent soft ferromagnetic properties with
a preferred easy axis of magnetization. 相似文献
148.
Dylan M. Copeland Jayadeep Gopalakrishnan Joseph E. Pasciak. 《Mathematics of Computation》2008,77(264):1941-1965
We present a mixed method for a three-dimensional axisymmetric div-curl system reduced to a two-dimensional computational domain via cylindrical coordinates. We show that when the meridian axisymmetric Maxwell problem is approximated by a mixed method using the lowest order elements (for the vector variable) and linear elements (for the Lagrange multiplier), one obtains optimal error estimates in certain weighted Sobolev norms. The main ingredient of the analysis is a sequence of projectors in the weighted norms satisfying some commutativity properties.
149.
Xue L Kovalev A Thöle F Rengarajan GT Steinhart M Gorb SN 《Langmuir : the ACS journal of surfaces and colloids》2012,28(29):10781-10788
The tip shape of contact elements in hairy adhesion systems is crucial for proper contact formation and adhesion enhancement. While submicrometer terminal contact elements show much better adhesion performance than their larger counterparts, shaping their tips so as to maximize normal adhesion has remained challenging. We prepared durable nanorod arrays consisting of stiff, highly entangled thermoplastic polymers with rationally shaped tips by replication of anodic aluminum oxide (AAO). Nanorod arrays with pancake-like tips showed pronounced normal dry adhesion already for small loading forces. For small loading forces, adhesion forces significantly exceeded the loading forces. Both the absence of hysteresis in force/displacement curves and the pronounced durability of the nanorods in series of repeated attachment/detachment cycles suggest that the nanorods behave like elastic springs. Experimental load-adhesion curves were reproduced with a modified Schargott-Popov-Gorb (SPG) model, assuming that contacts between probe and individual nanorods are sequentially formed with increasing indentation depth. 相似文献
150.
Ce doped ZnO nanoparticles (Zn1−xCexO, x = 0.0, 0.05 and 0.1) have been synthesized by sol–gel method at annealing temperature of 500 °C for 1 h under Ar atmosphere.
The synthesized samples have been characterized by powder X-ray diffraction (XRD), energy dispersive X-ray studies, UV–Visible
spectrophotometer and fourier transform infrared (FTIR) spectroscopy. The XRD measurements indicate that the prepared nanoparticles
have a hexagonal wurtzite structure and CeO2 crystallites. The calculated average crystalline varied from 21.97 to 15.62 nm with increase in Ce concentrations. The increase
in lattice parameters reveals the substitution of Ce into ZnO lattice. The presence of functional groups and the chemical
bonding is confirmed by FTIR spectra. PL spectra of the Zn1−xCexO system show that the shift in near band edge emission from 386 to 363 nm and a shift in blue band emission from 517 to 485 nm
which confirms the substitution of Ce into the ZnO lattice. 相似文献