Self-assembled lamellar structures with functionalized single wall carbon nanotubes

Highly ordered self-assembled multi-layer structures with denatured collagen wrapped single wall carbon nanotubes and surfactant systems were obtained through bioinspired methodology.     

Low-energy Raman-active phonons of multiwalled carbon nanotubes

Received: 8 April 1998/Accepted: 9 April 1998     

Doping of Carbon Nanotubes by Heavy Alkali Metals

Abstract

Multiwall (MWNT) and single wall (SWNT) carbon nanotubes were intercalated with heavy alkali metals. From the point of view of their composition, alkali 2D superlattice, EPR and ¹³C NMR characteristics, the intercalation compounds of MWNT (1^st and ^2nd stage) are close to their parent GIC. An expansion of the 2D triangular lattice of SWNT bundles was clearly detected, showing that the alkali atoms are intercalated in the free space between the tubes.     

TEMPERATURE DEPENDENCE OF CHLOROPHYLL(IDE) SPECTRAL SHIFTS and PHOTOACTIVE PROTOCHLOROPHYLLIDE REGENERATION AFTER FLASH IN ETIOLATED BARLEY LEAVES

Abstract— Absorbance spectroscopy at 77 K was used to investigate the effect of temperature on in vivo chlorophyllide shifts and photoactive protochlorophyllide regeneration after a saturating flash, which transformed all protochlorophyllide to chorophyllide. Photoactive protochlorophyllide present in darkness was stable up to 40°C. The rate of Shibata shift and protochlorophyllide regeneration after flash were strongly temperature dependent in the range 0–25°C. At 0°C, the shift was still observed but no regeneration occurred. Only slight effects were observed in the range 25–40°C. At all temperatures, the process of protochlorophyllide regeneration was significantly slower than the Shibata shift. The final chlorophyll shift from 672 to 674 nm was observed up to 40°C. The implication of these results concerning the pigment-protein interactions during the Shibata shift are discussed.     

One step synthesis of highly crystalline and high coercive cobalt-ferrite nanocrystals

Highly crystalline and almost monodisperse spinel cobalt-ferrite nanocrystals are synthesized in a one step process, which has very high coercivity at 10 K and exhibits superparamagnetic behaviour at 300 K.     

Inverse Filtering and Linear Prediction as New Analytical Approaches to Analyze the Change of Absorbance Spectra in Visible Spectroscopy: in vivo Study of Protochlorophyll(ide) Phototransformation

Abstract— The common approach of analyzing spectra by derivation is known to be inadequate for kinetic studies in visible spectroscopy (R. I. Sharger, Photochem. Photobiol. 38, 615-617, 1983) because the side-lobes height introduces artifacts and reduces readability in three-dimensional graphic representation. In this study we present for the first time a parametric method that enables the use of inverse filtering and linear prediction for kinetic investigation in visible spectroscopy in cell biology studies. The protochlorophyll(ide) phototransformation at room temperature (295 K) was used to demonstrate the performance of this analytical approach. The change of absorption spectra in etiolated barley leaves was analyzed after being illuminated by a 50 ms flash.     

Study of structural and electronic transport properties of Ce-doped LaMnO3

The structural and electronic transport properties of La_1−x Ce _x MnO₃ (x=0.0–1.0) have been studied. All the samples exhibit orthorhombic crystal symmetry and the unit cell volume decreases with Ce doping. They also make a metal-insulator transition (MIT) and transition temperature increases with increase in Ce concentration up to 50% doping. The system La_0.5Ce_0.5MnO₃ also exhibits MIT instead of charge-ordered state as observed in the hole doped systems of the same composition.