Laser Pyrolysis of Hydrocarbons in Synthesis of Soot Containing Fullerenes

Abstract

Using a high power CW CO₂ laser, the pyrolysis in a flow reactor of different hydrocarbons/oxidizer mixtures with/without sensitizer lead to soots containing weightable quantities of fullerenes which were identified by FTIR spectroscopy, high performance liquid chromatography (HPLC) and time-of-flight mass spectrometry. The C₆₀ and C₇₀ quantification was done by HPLC. The FTIR spectroscopy of toluene extracts from the soots and of exhaust gases allowed to discuss some aspects concerning the influence of sensitizer (SF₆) addition as well as of the oxidiser (O₂/N₂O) on the fullerene production in laser pyrolysis of benzene-based mixtures.     

Application of synthetic-aperture radars for measuring the Faraday rotation angle

The influence of the ionosphere on polarization characteristics of the electromagnetic radiation of a spacebome synthetic-aperture radar is analyzed. The value of the Faraday rotation angle of a linearly polarized wave radiated by this radar into the ionosphere is estimated for a comparatively long-wave band. A technique is proposed for determining the Faraday rotation angle by measuring the reflectivity of the Earth’s surface with a polarimetric radar. This technique is independent of the mapped geometry and orientation of reflected elements of the Earth’s surface.     

Cultural accommodation: Hybridity and the framing of social obligation.

Implications of cultural accommodation–hybridization were explored within the framework of individualism–collectivism. Individualism highlights the personal and centralizes individuals as the unit of analyses, whereas collectivism highlights the social and contextualizes individuals as parts of connected social units. In 2 experiments, the ways in which individualism, collectivism, and identity salience influence social obligation to diverse others was explored. The authors varied the personal goal interrupted (achievement–pleasure), the target (individual–group), and focus (in-group–larger society) of social obligation within subjects. The authors hypothesized that collectivism would increase obligation to the in-group when identity was made salient; that individualism alone would dampen social obligation; and that cultural accommodation–hybridization (being high in both individualism and collectivism) would increase obligation to larger society. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Long Term Strength of Structural Adhesive Joints

The long term static strength of adhesive joints is analyzed in terms of a modified Prot method and sustained load tests. Data from the failure times under different loading rates are used to predict the static stress that an adhesive joint will withstand for an infinite time, i.e., the endurance limit. Despite theoretical shortcomings, the method is found to give reasonable estimates of the endurance limit as determined by standard sustained load tests. The ratio of the short term lap shear strength to the endurance limit is found to be independent of adhesive modulus, temperature, and sample geometry. For engineering calculations on lap shear structural adhesive joints under a static load (at 23°C, 50% R.H.), the endurance limit may be assumed to be equal to 0.25 of the short term strength.     

Electrochemical method for characterization of graphite-aluminium chloride intercalation compounds

The electrochemical behaviour of different graphites in molten lithium chloroaluminate electrolyte was studied using the potentiodynamic method. The oxidation currents observed at potentials below chlorine evolution are related to the oxidation of graphite during aluminium chloride intercalation.     

The influence of cardiac frequency on the hemodynamic consequences of mitral stenosis (author's transl)

In eleven patients with isolated mitral stenosis and regular sinus rhythm a right cardiac catheterization was performed and the wedged pulmonary capillary pressure recorded at rest and during electrical pacing of the right atrium at successive frequencies of 100, 120, 140, and, occasionally, 160 and 180 beats/min, while cardiac output was estimated by the Fick's principle. In all cases a significant elevation of pulmonary capillary pressure with a simultaneous reduction in cardiac output was obtained. The rise of wedged pulmonary pressure was proportional to the increment in cardiac frequency and related also to the calculated area of the mitral valve. The influence of active atrial contraction upon pulmonary pressure and cardiac output is discussed and comparisons with other studies are made. Emphasis is made on the value of atrial pacing as a diagnostic method in mitral stenosis, especially in cases in whom classical effort manoeuvres can not be applied or are insufficient to rise cardiac frequency.     

The plastic-crystalline phase of succinonitrile as a universal matrix for solid-state ionic conductors

Solid ionic conductors are actively sought for their potential application in electrochemical devices, particularly lithium batteries. We have found high ionic conductivity for a large variety of salts dissolved in the highly polar medium based on the plastic-crystal form of succinonitrile (N[triple bond]C[bond]CH(2)[bond]CH(2)[bond]C[triple bond]N). Its high diffusivity, plasticity and solvating power allowed the preparation of a large number of materials with high ionic conductivity, reaching values of 3 mS cm(-1) at 25 degrees C (two orders of magnitude above polymers). Their ease of preparation and processing allowed us to study the influence of the solute on ionic conduction within this medium. Comparisons revealed a dichotomy between plastic crystals and conventional polymer media. The usefulness of these new, easily processed electrolytes was asserted in electrochemical tests with lithium intercalation electrodes.     

High-power InP MISFETs

InP MISFETs with SiO2 as the gate insulator and a deep channel recess have been fabricated. At 9 GHz the highest power output with 4 dB gain was 3.5 W/mm gate width with 33% power added efficiency. This power is more than twice that of the best GaAs MESFET.