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91.
Venkatesan Jayachandran Dalavi Pandurang Appana Seong Gi Hun 《Journal of Cluster Science》2022,33(6):2383-2392
Journal of Cluster Science - Clinically, implant-related bone infections are a serious concern as they reduce the success rate of grafting techniques and increases the risk of morbidity. Clinicians... 相似文献
92.
Zhu Diao M. Abid P. Upadhyaya M. Venkatesan J.M.D. Coey 《Journal of magnetism and magnetic materials》2010,322(9-12):1304-1306
The magnetization curves of arrays of near-spherical soft ferromagnetic particles are compared with those of quasi-two-dimensional dots with similar radius prepared by a rapid e-beam lithographic technique. Curves for the three-dimensional particles are anhysteretic and fit a M(H)/Ms=tanh(cμ0H) law, whereas the two-dimensional arrays show irreversible segments in the first and third quadrants where the planar vortex state transforms to a collinear state by discontinuous rotation of magnetization about an axis perpendicular to the vortex axis. The additional symmetry of the spherical particle allows this rotation to occur continuously, without energy barriers due to the demagnetizing field. 相似文献
93.
Composite cathode materials produced by integrating isostructural (2D-layered) compounds LiNiO2, LiCoO2, and Li2MnO3 (Li(Li1/3Mn2/3)O2) have been investigated utilizing a compositional phase diagram. The samples were characterized by multiple techniques to
establish structure–property relationships. Specifically, for structural characterization, powder X-ray diffraction, scanning
electron microscopy, thermo-gravimetric analysis, and X-ray photoelectron spectroscopy were carried out. For properties, electrochemical
characterization was carried out. The best composition showed a discharge capacity of 244 mAh/g (C/15 rate) in the testing
range of 4.6–2 V, with good coulombic efficiency and cyclability. 相似文献
94.
P. Venkatesan Soumen Das M. Muthu Rama Krishnan Chandan Chakraborty Koel Chaudhury Mahitosh Mandal 《Micron (Oxford, England : 1993)》2010,41(3):247-256
Analysis of changes in cancer cell morphology and cytoskeletal element induced by external stimuli is focus of current cancer chemotherapeutic studies. Cancer cell cytoskeleton is complex network of interwoven protein fibers composed of microtubules, microfilaments and intermediate filaments. These interwoven protein fibers are responsible for maintaining cell morphology, movement, adhesion and transmembrane signal transmission. In this study, morphological and cytoskeletal changes induced by AEE788 and/or Celecoxib on colon cancer cell HCT 15 were analyzed using advanced microscopic techniques. Cell proliferation assay was used for determining IC50 of AEE788 and/or Celecoxib on HCT 15. Confocal microscopic analysis of AEE788 and/or Celecoxib treated HCT 15 was performed using Rhodamine-Phalloidin (actin stain) and Hoechst 33342 (nuclear stain). Atomic force (AFM) and scanning electron microscopic (SEM) studies were also performed to analyze cell morphology and cell wall extension (filopodia and lamellipodia). In addition, quantitative analysis of morphological parameters was studied using cellular image processing technique. This is the first report that combination of AEE788 and Celecoxib additively increase growth inhibition and cell death on human colon cancer cell HCT 15 as estimated by cell proliferation assay. Morphological analysis of AEE788 or Celecoxib treated HCT 15 cell for 24 h have not revealed significant change in morphology under phase contrast microscopy. But, slight morphological changes were observed in combination (AEE788 + Celecoxib) treated HCT 15 for 24 h. In contrast, high resolution confocal laser fluorescence and atomic force microscopic studies have revealed cell shrinkage, disorganized actin filament and, loss of filopodia and lamellipodia. These changes were more prominent in combination of AEE788 and Celecoxib treated HCT 15 than either drug alone. These results may suggest antiproliferative and antimetastatic activity of AEE788 and/or Celecoxib. Quantitative analysis of morphological parameters using cellular image processing technique have shown decrease in mean area, perimeter, compactness and eccentricity of combination drug treated cells than either drug alone. These results further support the confocal and AFM study. Scanning electron microscopic study of AEE788 and/or Celecoxib treated HCT 15 has also shown morphological changes and loss of filopodia and lamellipodia. In conclusion, this investigation of morphological and cytoskeletal changes using advanced microscopic techniques present a significant foundation for evaluating anticancer activity of a drug and form a new strategy for evaluating effect of AEE788 and/or Celecoxib on colon cancer. 相似文献
95.
Natarajan A Mague JT Venkatesan K Arai T Ramamurthy V 《The Journal of organic chemistry》2006,71(3):1055-1059
Volume-demanding cis-trans photoisomerization of the aromatic substituted alkenes 1-3 in the solid state at room temperature and at 50 degrees C is presented. Alkene 3 did not undergo the cis-trans isomerization in the solid state either at room temperature or at 50 degrees C. The importance of the presence of void space near the reaction center to facilitate the large volume change during cis-trans photoisomerization is discussed. 相似文献
96.
Rajaram Mahalakshmy Rangarajan Venkatesan Pillutla Sambasiva Rao Ramu Kannappan Thekkel Madan Rajendiran 《Transition Metal Chemistry》2004,29(6):623-629
Two new unsymmetrical binucleating ligands, 2-[bis(3-N, N-dimethylaminopropyl)-aminomethyl]-6-[prolin-1-yl)methyl]-4-bromophenol [H 2L1] and 2-[bis(3-N, N -dimethylaminopropyl)aminomethyl]-6-[prolin-1-yl)methyl]-4-methylphenol [H2L2], and their dicopper(II) complexes with different exogenous bridging motifs (OAc, Br and Cl) have been prepared and characterized by spectral, electrochemical, magnetic and e.p.r. studies. Electrochemical studies indicate the presence of two irreversible reduction peaks in the cathodic region. Variable temperature magnetic susceptibility studies of the complexes show that the extent of antiferromagnetic coupling increases in the order: OAc–< Cl–< Br–. Broad isotropic or axial symmetric spectral features are observed in powder e.p.r. spectra of the complexes at 77K. A comparison of the electrochemical and magnetic behaviour of the complexes derived from the ligands is discussed on the basis of an exogenous bridge as well as the substituent at the para position of the phenolic ring. 相似文献
97.
Rajendiran Thekkel M. Kannappan Ramu Mahalakshmi Rajaram Venkatesan Rangarajan Sambasiva Rao Pillutla Govindaswamy Lakshmanan Velmurugan Devadasan 《Transition Metal Chemistry》2003,28(6):644-649
The synthesis, X-ray and e.p.r. spectral studies of a 3d–4f couple are described here. The crystal structure of [Cu(salbn)Gd(NO3)3·H2O], (2), salbn = N,N-butylenebis(salicylideaminato), has been determined by X-ray crystallography. Compound (2) crystallizes in the monoclinic system, space group p21/n, with a = 9.025(1), b = 22.912(1), c = 12.790(1) Å, = 99.36(1), Z = 4. The deviations of the four coordinating atoms (O(1)O(2)N(1) and N(2) of salbn and the copper atom is displaced from the plane in spite of the lack of any apical ligand. The gadolinium(III) ion is nine-coordinated by the two oxygen atoms of the salbn moiety, three bidentate nitrate ions and one water molecule. The geometry of GdIII can be described as a square antiprism, in which compound CuII and GdIII are bridged by the two phenolic oxygens of salbn. The CuII–GdIII distance is 3.269(1) Å. The bridging core CuO2Gd is a butterfly shape. Significant distortion was observed for the complex having the larger diamino string. The title compound exhibits seven e.s.r. transitions with |D| = 0.0467 cm–1, which demonstrates the existence of zero field splitting. This outcome indicates that compound (2) consists of a perfectly isolated dinuclear Cu–Gd core and steric bulk alters the dihedral angle in the Cu–O–Gd bridge. 相似文献
98.
99.
H. Anandalakshmi T. M. Rajendiran R. Venkatesan P. Sambasiva Rao 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2000,56(14)
Single crystal EPR studies of VO(II)-doped magnesium potassium Tutton’s salt have been carried out at room temperature. The results indicate that the paramagnetic impurity has entered the lattice, both substitutionally and interstitially and the maximum hyperfine for the substitutional site along the a axis corresponds to the minimum hyperfine for interstitial site and vice versa. The spin Hamiltonian parameters obtained from single crystal data for these sites are: Site 1, g||=1.954(1); g=1.998(1), A||=19.80(2) mT; A=7.61(2) mT; Site 2, g||=1.997(1); g=1.952(1), A||=7.66(2) mT; A=19.85(2) mT. Superhyperfine from ligand protons have been observed at certain orientations for Site 2 impurity. Powder spectrum shows a set of eight parallel and perpendicular features indicating the presence of only one site and these values matched with Site 1 values. From these observations, it has been concluded that the two vanadyl impurities are approximately at right angles to each other. Cooling the sample to 77 K does not change the spectra appreciably. The admixture coefficients have been calculated from Site 1 data, which agree well with the reported values. 相似文献
100.
R. Poonguzhali R. Venkatesan T.M. Rajendiran P.S. Rao R.V.S.S.N. Ravikumar Y.P. Reddy 《Crystal Research and Technology》2000,35(10):1203-1207
Magnesium Potassium Phosphate Hexahydrate (MPPH), is analogous to the bio‐mineral struvite. Vanadyl doped MPPH crystals are grown by slow evaporation technique. EPR and optical absorption studies are carried out at room and liquid nitrogen temperatures. Spin‐Hamiltonian, crystal field and bonding parameters are evaluated. 相似文献