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Editorial

4th International Conference on Polymer – Solvent Complexes and Intercalates

Evaluation of the Influence of Microwaves in the Structure of Silica Gels

In this work we studied the influence of microwaves in the pore structure of silica gels obtained via sol-gel polymerization process. We analised the feasibility of replacing conventional heating by microwave heating during drying. Structural parameters such as specific volume of pores (Vp), specific surface area (Sp)…

How are colloidal suspensions that age rejuvenated by strain application?

We present here a microscopic study of the effect of shear on a dense purely repulsive colloidal suspension. We use multispeckle diffusing wave spectroscopy to monitor the transient motions of colloidal particles after being submitted to an oscillatory strain. This technique proves efficient to record the time evoluti…

Raman Spectroscopy and Field Emission Measurements on Catalytically Grown Carbon Nanotubes

We used microcontact printing to pattern a silicon surface with an iron-containing catalytic solution. Multiwall carbon nanotubes were subsequently grown on the patterned areas by chemical vapor deposition at temperatures between 650 and 1000 °C. We demonstrate that the diameter of the catalytically grown multiwall na…

Aging of polymeric and composite insulating materials. Aspects of interfacial performance in aging

Aging of polymeric and composite materials is reviewed mainly from the standpoint of their interfacial performance. Insulating materials can be divided into simple polymers and composites. Polymers for power cables, transformers, insulators and rotating machines consist of thermoplastics such as PE, PET and PPS, elast…

The metal‐insulator transitions of VO 2 : A band theoretical approach

Abstract The results of first principles electronic structure calculations for the metallic rutile and the insulating monoclinic phase of vanadium dioxide are presented. In addition, the insulating phase is investigated for the first time. The density functional calculations allow for a consistent understanding of all…

Vibrational Analysis of Palygorskite and Sepiolite

Abstract Lattice dynamic calculations for the sepiolite and palygorskite structures using polarized Raman and FTIR spectra provide a fundamental basis for interpreting spectral features by assigning vibrational modes. The Si-O stretch and O-Si-O bond bending force constants determined for palygorskite are similar to e…

On the quantum and classical scattering times due to charged dislocations in an impure electron gas

We derive the ratio of transport and single particle relaxation times in three and two - dimensional electron gases due to scattering from charged dislocations in semiconductors. The results are compared to the respective relaxation times due to randomly placed charged impurities. We find that the ratio is larger than…

The high-pressure alpha/beta phase transition in lead sulphide (PbS): X-ray powder diffraction and quantum mechanical calculations

The high-pressure behaviour of PbS was investigated by angular dispersive X-ray powder diffraction up to pressures of 6.8 GPa. Experiments were accompanied by first principles calculations at the density functional theory level. By combining both methods reliable data for the elastic properties of rock-salt type alpha…

Geomagnetically induced current effects on transformers

Geomagnetically induced currents (GICs) can cause saturation of the magnetic circuit of transformers in a power system. This saturation can increase the MVAr absorption of the transformers, leading to voltage-control problems, generating significant harmonic currents, and cause heating of the internal components of th…

Free and Trapped Injected Carriers in C60 Crystals

We report on the conductance from two-contact carrier injection in C60 single crystals. In the nonlinear regime, the current and voltage obey a power law, I \~ V^m, where m can be as high as 10 at room temperature. This nonlinear behavior - the resistance decreases by 6 orders of magnitude without saturation - is amon…

Local studies of the ferromagnetic ordering temperature suppression in SrRuO3

In order to gain insight into suppression of the ferromagnetic ordering temperature, local studies utilizing 99,101Ru zero-field spin-echo NMR, along with complimentary magnetization, high-angle x-ray diffraction, and Ru K-edge XAFS measurements, have been carried out on samples of SrRuO3 annealed at both "ambient" (a…

Synthesis and properties of azo dye aligning layers for liquid crystal cells

The synthesis and properties of azo dyes that can be used for photoaligning liquid crystals (LCs) have been investigated. The structures and the synthetic procedure for the azo dyes are presented. The photoaligning of azo dyes takes place purely due to the reorientation of the molecular absorption oscillators perpendi…

Subunit Exchange of Multimeric Protein Complexes

The subunit exchange of the small heat shock proteins (sHSPs) PsHSP18.1 from pea and TaHSP16.9 from wheat has been monitored in real-time using nanoelectrospray mass spectrometry. By preserving the noncovalent interactions between subunits in the mass spectrometer, we show that these proteins are dodecameric. After mi…

Progress in electrothermal life modeling of electrical insulation during the last decades

This paper has the purpose of highlighting the achievements during the last decades in life modeling under electrothermal stress. Phenomenological and physical models are examined, considering also a statistical approach, with applications to experimental results.

UNCOUPLING OF SILICON COMPARED WITH CARBON AND NITROGEN METABOLISMS AND THE ROLE OF THE CELL CYCLE IN CONTINUOUS CULTURES OF THALASSIOSIRA PSEUDONANA (BACILLARIOPHYCEAE) UNDER LIGHT, NITROGEN, AND PHOSPHORUS CONTROL 1

The elemental composition and the cell cycle stages of the marine diatom Thalassiosira pseudonana Hasle and Heimdal were studied in continuous cultures over a range of different light‐ (E), nitrogen‐ (N), and phosphorus‐ (P) limited growth rates. In all growth conditions investigated, the decrease in the growth rate w…

Thermal Ablation of Tumors Using Magnetic Nanoparticles

RATIONALE AND OBJECTIVE: Feasibility of a new interventional procedure for the treatment of breast cancer called "magnetic thermal ablation" was examined under in vivo animal conditions. The method consists in the intratumoral application of iron oxide particles and the exposure of the breast to an alternating magneti…

FTIR Study of Adsorption and Photoassisted Oxygen Isotopic Exchange of Carbon Monoxide, Carbon Dioxide, Carbonate, and Formate on TiO2

In-situ FTIR has been employed to investigate adsorption and photoassisted oxygen scrambling of CO, CO 2, CO 3, and HCOO on powdered TiO 2 with 18 O 2 . As clean TiO 2 is exposed to CO at 35 °C, the IR frequencies of adsorbed CO shows that CO is bonded to Ti ions with an oxidation state +4 or less. The CO molecules th…

Structural, Luminescence, and NMR Studies of the Reversible Binding of Acetate, Lactate, Citrate, and Selected Amino Acids to Chiral Diaqua Ytterbium, Gadolinium, and Europium Complexes

The nature of the ternary complexes formed in aqueous media at ambient pH on reversible binding of acetate, lactate, citrate, and selected amino acids and peptides to chiral diaqua europium, gadolinium, or ytterbium cationic complexes has been examined. Crystal structures of the chelated ytterbium acetate and lactate…