A note on optimal floodlight illumination of stages

We consider the problem of illuminating a straight line segment with floodlights. The possible locations of the floodlights are given in advance and we want the total size of the floodlights to be minimum. We show that this problem admits a polynomial time algorithm even if we require that no two floodlights are placed at the same location.     

Alternate oils in fish feeds

Nearly half of the fish consumed as food worldwide are raised on fish farms rather than caught in the wild, as shown by FAO statistics. The increasing aquaculture of predatory carnivorous fish demands new sources of feed constituents, particularly oils at the moment. Common terrestrial plant oils contain only traces of the long‐chain polyunsaturated fatty acids. In connection with fish feed, especially the lack of n‐3 “marine fatty acids” is obvious. Recommendations on the required amounts of the fatty acids DHA (22:6n‐3) and EPA (20:5n‐3) exist from 1994. When plant oil‐based diets are fed during the growing phase and replaced by a fish oil‐based diet during a period prior to slaughter, most of the beneficial lipid composition of fish in terms of human dietary recommendations is restored. Little attention has been focused on the fish welfare in connection to substitution of dietary oil sources, and studies are still scarce. New fish diets will rely heavily on the use of alternate ingredients such as plant oils also for carnivorous cold‐temperate water fish species. In the future, an addition of synthetic or GMO‐produced “marine” fatty acids is a possible scenario. The aim of this review is to highlight some plant oils used in fish feeds, with special emphasis on compounds other than fatty acids. We also include some results from an ongoing study, where the effect of dietary soy oil on gonad maturation in Atlantic cod (Gadus morhua) is indicated.     

Glass and glass-ceramic coatings, versatile materials for industrial and engineering applications

Among various coating systems for industrial and engineering applications, glass and glass-ceramic coatings have advantages of chemical inertness, high temperature stability and superior mechanical properties such as abrasion, impact etc as compared to other coating materials applied by thermal spraying in its different forms viz. PVD, CVD, plasma, etc. Besides imparting required functional properties such as heat, abrasion and corrosion resistance to suit particular end use requirements, the glass and glass-ceramic coatings in general also provide good adherence, defect free surface and refractoriness. Systematic studies covering the basic science of glass and glass-ceramic coatings, the functional properties required for a particular end-use along with the various fields of application have been reviewed in this paper.     

Effect of noble metals in the decomposition of nitrous oxide over Fe-ferrierites

The decomposition of nitrous oxide was studied over Fe-ferrierite, Me-ferrierites and Fe/Me-ferrierites (Me: Pt, Rh and Ru). Flow as well as batch experiments were carried out and showed a synergy between Fe and Me ions. Ions of noble metals in Fe-ferrierite increased the catalytic activity in the sequence Pt < Rh ≅ Ru. Addition of NO substantially decreased the decomposition of N₂O over Rh/ferrierite and Ru/ferrierite, but not over bimetallic ferrierites. NO _x species created during the decomposition of nitrous oxide alone as well as with addition of NO, and employment of nitrous oxide labeled with ¹⁸O allowed us to assume a changing decomposition mechanism in the presence of Me ions in Fe-ferrierites.     

Assessing disharmony and disaffection in intimate relationships: Revision of the Marital Satisfaction Inventory factor scales.

Previous research has identified 2 broad components of distress in intimate relationships: overt conflict, or disharmony, and emotional distance, or disaffection. Using confirmatory factor analysis, the authors derived 2 broadband scales of disharmony and disaffection from the Marital Satisfaction Inventory-Revised (D. K. Snyder, 1997), building upon previous measures of these constructs (D. K. Snyder & Regts, 1982) derived from the original instrument. The new scales demonstrated high internal consistency and test-retest reliability, as well as discriminative validity and convergent validity with independent criteria of relationship functioning. Distinct distributions of these scales in community and clinical samples suggested their complementary role in research on intimate relationships and assessment of couples in treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exergy analysis of a compression–absorption system for heating and cooling applications

An exergy analysis of a single‐stage compression–absorption system with R22‐E181 as the working fluid pair is carried out. Theoretical results obtained have been compared with those obtained from the experiment. Results show that the heat of mixing of the refrigerant vapour and solution at absorber and desorber contributes a significant amount to the internal entropy generation rates. A significant part of internal entropy generation rate is also due to non‐isentropic compression of refrigerant vapour at higher absorber pressure. The exergetic efficiency of the system increases with the increase in absorber pressure due to reduction in internal irreversibilities. Higher value of weak solution concentration along with the increase in solution concentration difference results in higher exergetic efficiency of the system. Thus, a compression–absorption system performs better when operated at higher absorber pressure, and an improved system performance can also be achieved with higher value of weak solution concentration with higher possible solution concentration difference. Copyright © 2008 John Wiley & Sons, Ltd.