On some relations of electrochemical,catalytic and photochemical charge transfer processes at electronic or ionic conductor surfaces

The different kinds of partial charge transfer (l, λ, m) occurring at metal and semiconductor electrodes are briefly reviewed. Subsequently, some related properties of partitioning processes at ionic conductor (membrane) interfaces are considered and conditions for introducing macroscopic partial charge transfer of l-type elucidated. In section 4, the types of partial charge transfer involved respectively in electrochemical, catalytic, photochemical and membrane transfer processes are surveyed.     

Calculation of heterogeneous phase equilibria in oxide-nitride systems: I. The Quaternary System C  Si  N  O

A newly set up computer program based on the mathematical principles suggested by M. Hillert was used to calculate the phase equilibria in the system CSiN0. These calculations include phase equilibria with the vapour phase. Several isothermic and T-c-sections of the ternary boundary systems and of the quaternary system are given.     

The nutritional and physiological impact of milk in human nutrition

The nutritional value of milk as an important source of energy, high‐quality protein, calcium, and riboflavin has been recognized for many years. Currently, the widespread use and promotion of milk in the U.S. as well as developing countries has been questioned. This review examines the nutrient composition of dairy products, factors that account for variability in composition of milk, milk processing, preservation, quality control, and contaminants (such as minerals, radionuclides, antibiotics, microorganisms and their metabolites, herbicides, and insecticides) in milk. Consumption patterns for milk and evidence for its nutritional value, especially in children, are presented. Milk consumption has been related to disease or conditions such as atherosclerosis, milk allergy, lactose intolerance, anemia, dental problems, and others. Recent recommendations for dietary changes for individuals in the U.S. and other developed countries could affect the use of milk. In addition, the use of feeding programs in the U.S. and developing countries which are based primarily on milk has been criticized. The preparation of new types of milk designed to offset certain difficulties encountered with cow's milk are now being evaluated in humans.     

Core/Rim Structure of Liquid-Phase-Sintered Silicon Carbide

Plasma etching in conjunction with scanning and analytical transmission electron microscopy was used to characterize the microstructure and microchemistry of silicon carbide sintered with yttrium-aluminum garnet (YAG). The SiC grains comprise a core/rim structure with small amounts of excess yttrium, aluminum, and oxygen being present in the rim while these elements are missing in the core. The core/rim interface was found to be coherent, and both the core and the rim are composed of the same polytype, predominantly the 6H structure. These results suggest that Ostwald ripening by solution and reprecipitation controls the sintering mechanism in this system.     

Plasmid DNA in a groundwater aquifer microcosm--adsorption, DNAase resistance and natural genetic transformation of Bacillus subtilis

Prokaryotes can exchange chromosomal and plasmid genes via extracellular DNA in a process termed genetic transformation. This process has been observed in the test tube for several bacterial species living in the environment but it is not clear whether transformation occurs in natural bacterial habitats. A major constituent of terrestrial environments are solid particles such as quartz, silt and clay, which have considerable surface areas and which make up the solid-liquid interfaces of the habitat. In previous experiments the adsorption of DNA to chemically purified quartz and clay minerals was shown and the partial protection of adsorbed DNA against DNAase I. In a microcosm consisting of natural groundwater aquifer material (GWA) sampled directly from the environment and groundwater (GW) both linear duplex and supercoiled plasmid DNA molecules bound rapidly and quantitatively to the minerals. The divalent cations required to form the association were those present in the GWA/GW microcosm. The association was stable to extended elution over one week at 23 degrees C. Upon adsorption, the DNA became highly resistant against enzymatic degradation. About 1000 times higher DNAase I concentrations were needed to degrade bound DNA to the same extent as DNA dissolved in GW. Furthermore, chromosomal and plasmid DNA bound on GWA transformed competent cells of Bacillus subtilis. However, in contrast to DNA in solution, on GWA the chromosomal DNA was more active in transformation than the plasmid DNA. The studies also revealed that in the transformation of B. subtilis Mg2+ can be replaced by Na+, K+ or NH4+. The observations suggest that in soil and sediment environments, mineral material with inorganic precipitates and organic matter can harbour extracellular DNA leaving it available for genetic transformation.     

Effect of tachistoscopic stimulation of subconscious oedipal wishes on competitive performance: A failure to replicate.

Studied the effects of subconscious oedipal wishes on the dart-throwing performance of 72 18–29 yr old undergraduate males. The research was designed (a) to replicate the study by L. H. Silverman et al (1978), who found that Ss' dart-throwing performance improved after they viewed the subliminal stimulus "beating dad is ok" and worsened after they viewed "beating dad is wrong"; (b) to see if dart-throwing behavior is also affected by supraliminal oedipal stimulation; and (c) to investigate the influence of priming (i.e., preexperimental arousal of oedipal wishes) on the effect of tachistoscopic stimulation. Previous results were not replicated despite close adherence to the Silverman et al methodology, nor were other significant effects found. Questions are raised about the ability to have an impact on subconscious oedipal wishes in a behaviorally observable way using this paradigm. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

CNT Based Elastomer‐Hybrid‐Nanocomposites with Promising Mechanical and Electrical Properties

CNT based elastomer‐hybrid‐nanocomposites prepared by melt mixing have been investigated showing promising results in technologically relevant electrical, mechanical, and fracture‐mechanical properties. It is demonstrated that the incorporation of CNT in silica‐filled natural rubber results in a good dispersion of the CNT. The materials show an enhanced mechanical stiffness and tensile strength, an increased modulus, and a high electrical conductivity with quite low amounts of CNT, though the tear resistance under dynamical loading is slightly reduced. Using DMA and dielectric spectra, a better understanding of the conduction mechanism, the polymer/tube interaction, and the filler networking in CNT nanocomposites is achieved.

     

Adaptive scheduling mechanism for IPTV over WiMAX IEEE 802.16j networks

A WiMAX technology is a very promising Broadband Wireless Access technology that is able to transmit different service types. This latter can have different constraints such as traffic rate, maximum latency, and tolerated jitter. The IEEE 802.16 Medium Access Control specifies five types of QoS classes: UGS, rtPS, ertPS, nrtPS, and BE. However, the IEEE 802.16 standard does not specify the scheduling algorithm to be used. Operators have the choice among many existing scheduling techniques. Also, they can propose their own scheduling algorithms. In this paper, we propose a scheduling strategy (Adaptive Weighted Round Robin, AWRR) for various Internet Protocol Television (IPTV) services traffic over 802.16j networks. Our scheme adapts dynamically the scheduler operation to according queue load and quality of service constraints. In particular, the proposed mechanism gives more priority to high definition television and standard definition television traffic by using two schedulers. The proposed scheduling algorithm has been simulated using the QualNet network simulator. The experimental results show that our scheduler schemes AWRR have a better performance than the traditional scheduling techniques for rtPS traffic, which allows ensuring QoS requirements for IPTV application. Copyright © 2012 John Wiley & Sons, Ltd.