Electrocatalytic hydrogenation of cyclohexanone: Simple dynamic cell design

The electrocatalytic hydrogenation of cyclohexanone has been investigated with catalytic powder particles made of metal nanoaggregates deposited on a nonconductive material such as activated carbon and alumina. The catalytic powder particles were suspended in the solution under vigorous stirring conditions. The brief contact of the powder particles with a porous carbon cathode was sufficient to form adsorbed hydrogen on the metallic nanoaggregates through water electrolysis and initiate the electrohydrogenation process. It is demonstrated that the key parameters of the electrohydrogenation process are both the nature of the metallic nanoaggregates and the nature of the non-conductive material. The hydrodynamics of the solution under vigorous stirring conditions have also been studied for the particular cell used in the present study.     

Anicteric cholestasis in a 75-year-old man

This presentation challenges the purveyors of the importance of "positive thinking" in the cure of cancer. Psychological support should allow the patient to come to terms with his or her situation in a way that works for that individual within a caring and realistic environment. In no way should psychological support add an extra burden to an already devastated patient. By forcing "positive mental attitude", health-care professionals are not allowing patients to face reality. Promoters of the "cure" that comes with positive thinking are quoted, as well as authors who question the promoters' intent and outcome. It is felt that "positive thinking" may be appropriate as one of many successful coping strategies. To attribute more to it or, worse, to insist that patients believe in its power to cure may be courting emotional disaster.     

Comparative nanoindentation of single crystals of hard and superhard oxidess

The results have been considered of the studies of the plastic flow initiation in nanoindentation of single crystals of hard and superhard oxides. It has been found that the transition from elastic to elastoplastic deformation in superhard brittle oxides is accompanied by the formation of essentially lower number of dislocations (by an order of magnitude) than in metals. The hardest oxides are sapphire, stishovite, and boron suboxide (B₆O). Up to now the reliable results of nanoindentation have been reported only for sapphire and stishovite. It has been defined that the stishovite hardness is considerably higher than that of sapphire (38 GPa and 28 GPa, respectively). At the same time if the hardness of nanocrystalline sapphire may be expected to be increased up to a limiting value of 48 GPa, the essential increase of the stishovite hardness should not be expected due to a shear softening of the lattice at pressures 40–45 GPa.     

Behavior of Boron in Molten Aluminum and its Grain Refinement Mechanism

The mechanism of heterogeneous grain refining of aluminum by ultrafine elemental boron particles was investigated. In order to facilitate the observation of the boron-aluminum interface, a boron filament was introduced in a melt at 1013 K (740 °C) containing different levels of Ti. The Al/B interface was studied using transmission electron microscopy and different phases were identified using the electron diffraction method. The experimental results showed that boron is dissolved in pure aluminum while its dissolution is inhibited in presence of titanium solute. A thin layer of TiB₂ formed at the surface of boron thickens with residence time in the melt. The mechanisms by which aluminum is crystallized on boron are discussed.     

Dots to dots: a general methodology to build local indicators using spatial micro-data

Empirical studies in regional science have so far largely relied on discrete conceptualizations of space and aggregated metrics, which do not take into consideration spatial heterogeneity and variability at the micro-level. This paper explores the use of these indicators when dealing with observations at the subregional level, based on micro-data sets that impose the conceptualization of spatial interactions in a continuous and multidirectional space. We propose a general methodology to build local indicators for spatial micro-data sets. Based on distance matrix and matrix calculations, some classical indices of specialization and diversity are extended to their local counterparts to explore the full spatial heterogeneity and variability of space. The methodology is applied to 9,839 establishments covering all economic sectors in the Lower St-Lawrence region (Quebec, Canada). We find that the distribution of the local indicator varies significantly with distance, which suggests that the effects of specialization or diversity are not constant over space. Treating space as continuous may become of prime importance, given that more individual data sets are now available, combined with the fact that the performance of microcomputers is still improving.     

Structure and properties of hot-pressed materials based on AlB<Subscript>12</Subscript>C<Subscript>2</Subscript>

The results are presented on the investigation of the structure and mechanical properties of hot-pressed materials based on AlB₁₂C₂ powders of sizes 50–150 nm. It is shown that the consolidated materials having mechanical properties comparable with boron carbide may be produced at essentially lower (by 270–300°C) sintering temperatures. It has been established that the heating rate at compressing affects the stoichiometry of the impurity phase containing Al, B, O, which define the difference in mechanical properties of the materials (a decrease of the heating rate results in the insignifical decrease of the material hardness and increase of the fracture toughness).     

Multipurpose electroslag remelting furnace for modern energy and heavy engineering industry

In 2011, a unique complex based on a multipurpose unit-type electroslag remelting (ESR) furnace is created to meet the demand for large high-quality solid and hollow billets for the products of power, atomic, petrochemical, and heavy machine engineering. This complex has modern low-frequency power supplies with a new control level that ensure a high homogeneity and quality of the billets and an increase in the engineering-and-economical performance of the production. A unique pilot ESR furnace is erected to adjust technological conditions and the main control system elements.     

Possibilities for controlling the characteristics of nitride and carbonitirde inclusions in a low-carbon austenitic steel

The mechanisms of formation of nonmetallic inclusions in a stabilized low-carbon austenitic steel Ch-68id are studied. Technologies for controlling the sizes and distribution of the nonmetallic inclusions are suggested.