Experimental Investigation on the Effects of Mixing Hot and Cold Water on the Concrete Properties in Ethiopia

In this article, the effect of replacing cement with silica fume and fine aggregate with copper slag has been investigated. For this research work, concrete of M40 grade is prepared and evaluated for fresh and harden concrete properties such as compressive strength, tensile strength and flexural strength. Further, the cement is replaced with silica fume at 0, 2, 4, 6, 8 and 10 % and fine aggregate replaced with copper slag at 0, 10, 20, 30, 40 and 50 %. Compressive strength, strength and Flexure strength have been tested. It is observed from the results that the use of silica fume and copper slag as partial replacement material improves mechanical properties of the concrete. Concrete with 40 % copper slag and 8 % silica fume shows better performance among all the mixes.

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Experimental Investigation of Performance of Spiral Coil in Spiral Tube Heat Exchanger

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.592-594.1564 ◽

2014 ◽

Vol 592-594 ◽

pp. 1564-1569

Author(s):

G.N. Deshpande ◽

Nitin V. Sali

Keyword(s):

Heat Transfer ◽

Experimental Investigation ◽

Heat Exchanger ◽

Cold Water ◽

Hot Water ◽

Spiral Coil ◽

Spiral Tube ◽

Tube Heat Exchanger ◽

Inside Diameter ◽

Spiral Shape

In the present work of experimental investigation, the heat transfer performance of Spiral Tube Heat Exchanger (STHE) is studied by manufacturing the heat exchanger. STHEs are known as excellent heat exchanger because it is compact in size and having high heat transfer ability. The STHE consists of copper coils in the spiral shape and placed inside the shell which is made of Stainless Steel. The spiral shape coil is made by bending the straight copper tube of 10 mm inside diameter. The heat exchanger uses 3 such spiral coil brazed with straight header tube of 25 mm inside diameter and at a distance of 15mm apart, the number of turn in a spiral coil is four. Pump is used for circulation of water in both circuits. Cold water is circulated through spiral coil which entered at the periphery and comes out from centre; hot water is entered at the bottom centre of shell and comes out from the top of the shell. The inlet temperature range of hot water and cold water is 50 to 80°C and 30 to 48°C. Mass flow rate range of hot water and cold water is from 0.0633 kg/s to 0.0833kg/s and 0.01 kg/s to 0.0833kg/s.

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Patient Involvement in Treatment Decision Making Can Help or Hinder Placebo Analgesia

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000179 ◽

2014 ◽

Vol 222 (3) ◽

pp. 165-170 ◽

Cited By ~ 2

Author(s):

Andrew L. Geers ◽

Jason P. Rose ◽

Stephanie L. Fowler ◽

Jill A. Brown

Keyword(s):

Patient Involvement ◽

Cold Water ◽

Prior Experience ◽

Water Immersion ◽

Treatment Decision ◽

Cold Water Immersion ◽

Not Given ◽

Placebo Analgesia ◽

Treatment Decision Making ◽

Immersion Experience

Experiments have found that choosing between placebo analgesics can reduce pain more than being assigned a placebo analgesic. Because earlier research has shown prior experience moderates choice effects in other contexts, we tested whether prior experience with a pain stimulus moderates this placebo-choice association. Before a cold water pain task, participants were either told that an inert cream would reduce their pain or they were not told this information. Additionally, participants chose between one of two inert creams for the task or they were not given choice. Importantly, we also measured prior experience with cold water immersion. Individuals with prior cold water immersion experience tended to display greater placebo analgesia when given choice, whereas participants without this experience tended to display greater placebo analgesia without choice. Prior stimulus experience appears to moderate the effect of choice on placebo analgesia.

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