Magnetic field reduction using high phase order lines

Ground level electric, and more recently magnetic, fields from overhead power transmission lines are increasingly important considerations in right-of-way specification, with states setting or planning to set edge-of-right-of-way limits. Research has been conducted on high-phase-order power transmission wherein six or twelve phases are used to transmit power in less physical space and with reduced electrical environmental effects compared with conventional designs. The first magnetic field testing verifies predictive methods for determination of magnetic fields from high-phase-order lines. Based on these analytical methods, field profiles are determined for lines of different phase order but comparable power capacity. Potential advantages of high phase order as a means of field mitigation are discussed     

Effects of effort attributional feedback on children's perceived self-efficacy and achievement.

40 children (aged 7–10 yrs) who lacked subtraction skills received didactic training in subtraction operations with effort attributional feedback concerning past or future achievement or no feedback. Attributional feedback for past achievement led to more rapid progress in mastering subtraction operations, greater skill development, and higher percepts of self-efficacy. Results of a multiple regression analysis show that percepts of efficacy and training process each accounted for a significant increment in the explained portion of variability in posttest skill. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inorganic elements in the tracheas of fire fatalities

Concentrations of elements were determined in tracheal specimeans of fatal fire casualties and of non-fire fatalities. Elevated concentrations of antimony, bromine, zinc, chromium, cobalt, iron, lead, cadmium and gold found in the group exposed to the fire environment were associated with deposition of soot. The presence of raised concentrations of antimony in fatalities was found to occur in association with increased content of carboxyhaemoglobin in blood and was greatest in fires involving major destruction of property. A relationship between the increased concentration of this element and the use of antimony containing fire-retardants in construction materials could not be demonstrated.     

Synthesis of Metal Phosphates Using SiP2O7

A new, alternative, route to the synthesis of metal phosphates, using SiP₂O₇ as a reagent, was studied. The reaction of SiP₂O₇ with metal oxides yields a solid mixture of silica and metal phosphates; its reaction with metal fluorides yields solid metal phosphates and gaseous mixtures of SiF₄ and POF₃ .     

Bedroom ventilation: Attitudes and policies

A behavioural study by Brundrett in 1977 indicated that in the U.K. a substantial number of persons slept with their bedroom windows open. Such a habit, if it prevailed during cold weather, could lead to considerable energy losses. However Brundrett's sample was small and the data, which were gathered in the summer, might reflect behaviour which varied with the seasons and so were biased. The present investigation questioned a larger sample during the winter. The questionnaire also invited respondents to cite the ill-effects from which they might suffer if their bedroom window were closed all night. The results generally confirmed Brundrett's indications regarding the prevalence of window opening. The reasons for it appear to be related to beliefs regarding ventilation and health. These could have their origins in the writings of Florence Nightingale.     

RAPID METHODS FOR DETERMINING THE HIGH MOLECULAR WEIGHT POLYPEPTIDE COMPONENTS OF BEER

Size exclusion chromatography and a coomassie blue dye-binding assay were used to investigate the high molecular weight polypeptide fractions of beer. Size exclusion chromatography using small colums of Sephadex G25, G50 (10 ml) and G75 (20 ml) together with an automated FPLC system enabled the rapid isolation of high molecular weight polypeptide fractions of beer. Size exclusion chromatography using small columns of Sephadex was investigated as a method for the determination of the total high molecular weight polypeptides in beer. The results from the analysis of a series of pilot brewery beers produced under standardised brewing conditions showed that the head retention value of a beer correlated with the content of high molecular weight polypeptide material regardless of the molecular weight fraction assayed. Both methods may be used to monitor the high molecular weight polypeptide content, predict the head retention value of a beer and are sufficiently rapid for routine use in the quality control laboratory.     

1H- and 13C-n.m.r. studies on naphtha and light distillate saturate hydrocarbon fractions obtained from in-situ shale oil

Shale oil, obtained from an in-situ oil shale experiment, from the Green River formation in Southwestern Wyoming was thermally fractionated into naphtha, light distillate, heavy distillate and residue fractions. The naphtha and light distillate fractions were further separated into saturates, olefins and aromatic subfractions. ¹H- and ¹³C-n.m.r. spectra and mass spectral data were obtained for the saturated hydrocarbons of the naphtha and light distillate fractions. Resonances in the n.m.r. spectra were assigned to normal alkanes and to methyl- and dimethyl-branched alkanes. The composition as determined by n.m.r. of the naphtha saturates was found to be ≈82% straight-chain alkanes with an average carbon-chain-length of ≈C₁₁ and ≈18% branched/cyclo-alkanes. The composition of the light distillate saturates was found to be ≈ 69% straight-chain alkanes with an average carbon-chain-length of ≈C₁₅and ≈31% branched/cyclo-alkanes. The dimethyl-branched alkanes in both saturate fractions were proposed to have the molecular substructure of saturated isoprenoids. In the naphtha saturates the isoprenoid substructure

is evident. However, in the light distillate saturates, both isoprenoid substructures,

and

, are evident. ¹³C spin-lattice re-laxation times also were determined for the dominant resonances observed in the spectra of the naphtha and light distillate saturates. Relaxation times for the molecular species in the naphtha saturate fraction were observed to be longer than those observed for the light distillate saturate fraction. It was found that the ratio of the overall average relaxation times for the naphtha and light distillate saturate fractions corresponded to the inverse ratio of the average molecular weights of each fraction as determined from average alkane carbon-chain-length determination. Intermolecular (segmental) motion of the carbon chain of the straight-chain alkanes in both saturate fractions is also evident from the relaxation time measurements.     

Pulse unfocusing within laser-fusion reactors

Most serious laser-fusion reactor studies involve an atmosphere of lithium vapor within the pulse cavity. The laser pulse ionizes the vapor, generating an ‘unfocusing’ refractive medium. Proper account of this effect may necessitate a lower vapor density than previously reported.     

FRACTIONATION OF HIGH AND LOW MOLECULAR WEIGHT COMPONENTS FROM WORT AND BEER BY ADSORPTION CHROMATOGRAPHY USING THE GEL SEPHADEX LH20

Column chromatography using the hydroxypropylated dextran gel Sephadex LH20 was used to fractionate the components of brewers' wort and beer. The elution profile of beer was investigated in detail and components identified. Fractions containing high molecular weight polypeptide material, small peptide material, free proline, phenylalanine, tyrosine and adenosine have been identified. These fractions are common to all beers investigated. This use of LH20 provides a simple and rapid technique for monitoring high and low molecular weight materials in beer production and may be used in diagnosis of beer problems. An example of the application of the LH20 elution profile to the analysis of an out of specification beer is described.     

MODEL REFERENCE ADAPTIVE CONTROL BASED ON LIAPUNOV'S DIRECT METHOD Part I: Theory and Control System Design†

The Liapunov design approach for model reference adaptive control (MRAC) is extended to include adaptive integral and setpoint control modes. The feasibility of the Liapunov approach is illustrated by designing a multi-variable MRAC system based on a fifth-order state space model of a pilot scale, double-effect evaporator. Simulation results are presented to demonstrate that the MRAC approach gives satisfactory control for a wide range of adaptive loop gains and despite very poor initial control policies.