Materials Literature
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Magnetotransport properties of quasi-two-dimensional thallium purple bronze were measured at different magnetic fields for H ∥ c . Huge positive magnetoresistance below the Peierls transition T P and Shubnikov-de Haas oscillation in the high-field range were found. In the charge-density-wave (CDW) state below T P , no…
The electrical resistivity and Hall effect for a single crystal of Tm 2 Fe 14 B have been measured over the range of temperature ( T ) from 4 to 600 K in magnetic fields of up to 5 T. The resistivity exhibits a small step-like rise at the spin-reorientation temperature T s , which is 311 K, and a broad minimum at 535…
A three-dimensional array of gold nanoparticles has been assembled on a nanostructured TiO 2 template by subjecting the colloidal gold suspension to a dc electric field (50−500 V). By controlling the concentration of gold colloids in toluene and the applied voltage, it is possible to control the thickness of nanostruc…
The combined effect of finite potential barriers and the dielectric mismatch between dot and matrix on excitonic properties of semiconductor quantum dots has been studied. To avoid the unphysical divergence in the self-polarization energy which arises for the simplest and profusely adopted step-like model of the diele…
Porphyrin and pyrene photoactive cores have been encapsulated within an isolating polymeric shell using an efficient and general strategy based on the use of dendritic initiators for the ring-opening polymerization of epsilon-caprolactone to yield functional core star polymers. The isolation of the core functionalitie…
A theoretical study of structural and electronic properties of boron compounds BN, BP, BAs and BSb is presented, using the full potential linearized augmented plane wave method. In this approach, the generalized gradient approximation was used for the exchange-correlation potential. Ground state properties such as lat…
Based on a simple model for ordering of hexagons on square planar lattice, an attempt has been made to consider possible structure of C(_{60}) fullerite in its low temperature phase. It is shown that hexagons, imitating fullerens oriented along (C_{3}) axes of \emph{sc} lattice, can be ordered into an ideal structure…
We present a critical theoretical study of electronic properties of silicon nanoclusters, in particular the roles played by symmetry, relaxation, and hydrogen passivation on the the stability, the gap states and the energy gap of the system using the order-N [O(N)] non-orthogonal tight-binding molecular dynamics and t…
In this work, we address issues pertinent to the understanding of the structural and electronic properties of Si_{1-x} Ge_{x}alloys, namely, (i) how does the lattice constant mismatch between bulk Si and bulk Ge manifests itself in the alloy system? and (ii) what are the relevant strain release mechanisms? To provide…
The effective exchange interactions of magnetic overlayers Fe/Cu(001) and Co/Cu(001) covered by a Cu-cap layer of varying thickness were calculated in real space from first principles. The effective two-dimensional Heisenberg Hamiltonian was constructed and used to estimate magnon dispersion laws, spin-wave stiffness…
The mechanisms and kinetics of the reduction of powdered Fe 2 O 3 and Fe 3 O 4 samples have been investigated under nonisothermal conditions to provide a detailed insight into the processes occurring. Both conventional linear heating temperature-programmed reduction (TPR) and constant rate temperature-programmed reduc…
A novel and simple preparation method for single monodisperse CdS nanoparticles with controllable size and stability against oxidation is presented. Double-hydrophilic block copolymers consisting of a solvating poly(ethylene glycol) PEG block and a poly(ethylene imine) PEI binding block have been used as effective sta…
Integral isoconversional methods may give rise to noticeable systematic error in the activation energy when the latter strongly varies with the extent of conversion. This error is eliminated by using an integration technique that properly accounts for the variation in the activation energy. The technique is implemente…
Amorphous carbon nitride films have been grown by ion beam assisted deposition (IBAD) under different process conditions. The films were found to be graphitic, with π bonds between C and N atoms and a [N]/[C] ratio below 0.3. There is a relationship between the contribution of electrons from C and N atoms to the π bon…
Since 2,3-bis( n -decyloxy)anthracene (DDOA) is a good gelling agent for a large number of solvents including propylene carbonate (PC), the electrochemical properties of organogel electrolytes based on DDOA have been investigated. The presence of tetraalkylammonium salts in DDOA/PC gels is shown to preserve the three-…
Lysine 2,3-aminomutase (LAM) catalyzes the interconversion of L-lysine and L-beta-lysine. The enzyme contains pyridoxal 5'-phosphate (PLP) and a [4Fe-4S] center and requires S-adenosylmethionine (SAM) for activity. The hydrogen transfer is mediated by the 5'-deoxyadenosyl radical generated in a reaction of the iron-su…
We solve the linearized Boltzmann equation for currents perpendicular to the planes of the layers for two semi-infinite metallic layers in the presence of diffuse and specular scattering at the interface. In particular, the variation of chemical potential within a mean-free path of the interface is investigated. The d…
A systemic study on the synthesis, characterization, degradation, drug release, and stability of nonlinear fatty acid terminated poly(sebacic anhydride) (PSA) is reported. Ricinoleic acid was transformed into a nonlinear fatty acid by esterification with fatty acid chlorides of C8-C18 chain length in the presence of p…
The effect of Fe doping $(<~10%)$ on polycrystalline samples of ${\mathrm{La}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_{3}$ has been studied by means of x-ray diffraction, resistivity, ac susceptibility, magnetization, and magnetoresistance measurements. Fe doping does not affect the lattice structure, but it weaken…
Orientational relaxation of supercooled o -terphenyl (OTP) is studied over a wide range of temperatures and time scales using optical heterodyne detected optical Kerr effect techniques. A combination of experimental setups made it possible to study the dynamics for greater than six decades of time (100 fs to hundreds…