Erosion Characteristics of Copper-Based Composite Electrodes in an Electric Arc of Variable Length with Transverse Gas Blowing

We present experimental data on the erosion of electrodes made of copper-based pseudoalloys during contact breaking at current amplitudes up to 150 kA in nitrogen at a pressure of ~2 MPa with transverse gas blowing. The electric-erosion characteristics of copper–iron pseudoalloy CuFe (85/15%) electrodes obtained by laser layer melting, as well as CuFe (70/30%) and CuW (25/75%) pseudoalloy electrodes fabricated by traditional powder technology (sintering of pressed powder compacts) are reported. The specific erosion of electrodes in variable-length arc amounts to ~1 mg/C, which somewhat exceeds the value observed for a fixed-length arc discharge gap.     

Annealing of Mineral-Like Host Matrices for High-Level Waste Immobilization

Inorganic Materials - We have studied the effect of annealing on the chemical and physical properties of mineral-like host matrices for immobilization of the rare-earth–actinide fraction from...     

Application of Modified Lignosulfonates in Adhesives for Insulation Board Manufacture Based on Mineral Wool

Extensive laboratory investigations and mill scale trials confirmed the applicability of ultrafiltrated high molecular weight Ca-ligno-sulfonates in adhesive composition with phenolic resin for insulation board manufacture based on mineral wool. Insulation materials produced with adhesive components with a formulation of lignosulfonate/PF resin between 10/90 and 30/70 have appropriate technical and commercial properties.     

Some compositional properties of seeds and oils of eightAmaranthus species

Grain of 21Amaranthus accessions (eight species) was analyzed for crude fat, fatty acid profiles (FAP), and vitamin E (tocopherols and tocotrienols). Contents of (1→3), (1→4) β-glucan were determined in 12 accessions (four species), and trypsin inhibitor activity (TIA) in 20 accessions (six species). FAP and vitamin E profiles were compared to those of barley, buckwheat, corn, lupin, oat, and wheat oils. Crude fat content ranged from 5.2 to 7.7%, and of the oils examined, amaranth oil was most similar in FAP to corn and buckwheat oils. Amaranth was higher than all but wheat and lupin in tocopherol content but was virtually devoid of tocotrienols, which have been shown to have hypocholesterolemic activity. Amaranth grain did not contain (1→3), (1→4) β-glucans and was low in trypsin inhibitor activity (≤4.3 trypsin units inhibited/mg). Any hypocholesterolemic effects of dietary amaranth are apparently due to substances other than (1→3), (1→4) β-glucans or tocotrienols.     

Programmed input of energy into the discharge chamber of a light-gas electric-discharge accelerator of bodies

The effect is investigated of the duration of electrical energy input into working gas and of discharge power profile on the launching velocity and efficiency of acceleration of bodies using a light-gas electric-discharge accelerator with a caliber of 30 mm. It is found that, for the same energy input to the arc or for the same pulsed pressure of working gas in the discharge chamber of the accelerator, the projectile velocity in the mode being programmed is 7–10% higher, and the efficiency of conversion of internal energy of working gas to kinetic energy of projectile is 2 or 3% higher, than those in the synchronous mode.     

Modeling of vial and ball motions for an effective mechanical milling process

Mechanical milling (MM) is referred to a solid state size reduction process where work materials in the form of coarse particulates are broken into the ultimate fineness by means of mechanical impact created by collisions of the work materials and the milling media which are placed inside a reciprocating vial. Many milling techniques have been so far developed to improve the process. However, the efficiency of MM process is still below satisfactory in terms of energy balance, where the energy consumed by the process of reduction is still very low compared to the energy supplied to perform the milling process itself. This contributes to high energy losses and proportionally to the span of processing time. Other major problems inherent in the process are contamination by the balls and the vial materials into the work materials, and process temperature that could influence the properties of milled materials. Since MM process utilizes the energy generated by impact upon the collisions of the balls against the work materials, it is important to understand the motions of the balls, the work materials, and the vial, which are the sources of the generation of impact energy. To obtain an optimized processing condition, the motions of vial and ball in relationship with the work materials should be designed in such a way to ensure the optimum impact energy is consumed by the work materials for the size reduction purposes. This paper presents a physical model for work materials, balls, and vial collisions based on different ways of motions. Using this model, higher impact could be achieved. These would lead to the reduction of milling time, contamination, as well as milling temperature.     

Investigation of solar declination

A new expression for solar declination angle calculation has been developed using data for four years of periodical changes. The accuracy of the proposed formula related to astronomical ephemerides is obtained using the method of the minimum sum of square errors. The calculated values vary between 1.285 and 2.776° for the selected whole year while the value for four years is 6.686°. The mean bias error differs between −0.009 and −0.050°. The standard deviation is 0.128 and 0.181, respectively. The equation proposed in this study can easily be used for solar declination computation for each day of a selected year.     

An experimental stand for investigating protective devices for high-voltage overhead lines

An experimental stand for investigating and testing lightning protection devices for aerial power lines is described. The stand is composed of an oscillation circuit modeling a power line with an industrial frequency of 50 Hz, a voltage of up to 10 kV, and a current amplitude in the circuit as high as 10 kA; a generator of short single current pulses with a voltage of up to 25 kV and a current amplitude of up to 30 kA, modeling a lightning discharge; and commutation, control, and diagnostic systems. The stand is used to investigate elements of multi-chamber arrester systems for protecting high-voltage overhead lines.     

A microgenetic approach to word association.

3 experiments were conducted to test certain general hypotheses derived from a microgenetic approach to word association. Association responses given under time pressure were compared with those given without time pressure in groups of college students. Word associations of schizophrenics and a group of hospital aides were similarly compared without time pressure. The results in part supported the hypothesis that word associations of the college students performing under time pressure would differ from those of the Ss without time pressure in the same way that responses of the schizophrenics would differ from those of the aides. (PsycINFO Database Record (c) 2010 APA, all rights reserved)