จำนวน Repository ( 822 )

Investigation of Chromium Carbide Precipitation and Corrosion Behavior on Stainless Steel AISI 304 for Welding Process Development
Investigation of Chromium Carbide Precipitation and Corrosion Behavior on Stainless Steel AISI 304 for Welding Process Development

This research is aimed at investigating the amount of chromium carbide (Cr23C6) in stainless steel AISI 304 by electrochemical technique testing in calculating the Pa values that corresponding to sensitization stage and the corrosion behavior. The results will carry on to developing the welding process. The specimens were produced with Shielded Metal Arc Welding method. Moreover it was bending at the angle 0 90 and 180 degree and the process finished on post-heat treatment with different cool down conditions are 800ºC annealed in air cooled 1100ºC annealed in water cooled and annealed 1100ºC in air cooled respectively. The results show that: first conditional is appeared the maximum amount of Pa value (Pa > 0.4) indicating that more precipitation of Cr23C6 in heat affected zone (HAZ) of specimen. The second conditional is not found the sensitization stage because when the specimens were annealed at high temperature the chromium carbide will break up and residual stress in HAZ will decrease. At last conditional is found the less amount of Pa value; the reason of using high temperature on annealing process will decrease chromium carbide but slowly air-induced cooling must pass the critical temperature then some Cr23C6 will appear at grain boundary and cause of high corrosion rate. Concerning to the corrosion behavior the second conditional present the lowest corrosion rate corresponding to the better-quality of passive film. Whereas the first conditional shown the highest corrosion rate and low quality of passive film. Thus 1100ºC annealed with water cooled is excellent condition for developing the welding process.

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Development of Electronic Test to Measure Students’ English Abilities of Rajamangala University of Technology Phra Nakhon
Development of Electronic Test to Measure Students’ English Abilities of Rajamangala University of Technology Phra Nakhon

The purposes of this research were to build and develop a standardized test used to measure English abilities compliant with the curriculum of the fourth-year students of Rajamangala University of Technology Phra Nakhon. There were two groups of the students namely the first group which consisted of 57 students who took the traditional pilot paper test and the latter which consisted of 63 students taking the electronic test via the Internet. The other purposes were to find out the students/users’ attitudes and satisfaction towards the use of the electronic test and to obtain a computer program prototype for measuring English abilities. The results were as follows: 1. The item analysis of the pilot paper test revealed that there were 64 items of appropriate difficulty index and discrimination power whereas that of the electronic test revealed that only 56 items had appropriate difficulty index and discrimination power. Even though the latter test had been improved the accepted items were fewer. This led to the assumption that the characteristics of doing an electronic test affected students’ decisions and made them guess more than when they took a paper test. 2. The questionnaires analysis of students’ satisfaction of using the electronic test program to measure their English abilities revealed that the overall arithmetic mean was 75.72. The highest scored item of 87.59 percent was “I think this e-test program is useful”; and the lowest scored item of 66.21 percent was “I think the screen format is interesting”. Moreover there were 11 users who showed their positive opinions towards the e-test program which was 18.97 percent of the latter group.

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Development of Green Energy Block Made from Paper Mill Waste Sludge
Development of Green Energy Block Made from Paper Mill Waste Sludge

Sludge from paper mill wastewater treatment plant is the residual composed of fibres fibre particles and miscellaneous debris. Sludge with high fibre contents were collected from BP paper mill industry. They were retreated by 2 days drying and mixing dried sludge with tapioca starch as ratios were: 100:0 95:5 90:10 85:15 and 80:20(sludge: tapioca starch). To make the green energy block by using screw-press machine compressed sludge that mixed with various ratios of tapioca starch. A size of green energy block was 6 inches diameter 2 inches high and 150 g. weight. Energy values were tested by using Bomb-calorimeter measurement instrument. The results of testing found: the best ratio of green energy compressed for high heating value was 95:5(sludge : tapioca starch by weight) and the maximum heating value was about 19638 J/g. This green energy block made from waste of paper mill wastewater treatment plant is a way of recycle waste to be energy and reducing waste from industry.

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Development of Additional Skill Toy from dust mite defending Fabric.
Development of Additional Skill Toy from dust mite defending Fabric.

The objective of this research is to develop the additional skill toy from dust mite defending fabric. There are categories into three products : 1) Non decorated dust mite defending Fabric 2) Printed cartoon of dust mite defending Fabric 3) Covered colorful cloth of dust mite defending fabric. It can be divided into 3 patterns of this product : 1) the geometric style (triangle square hexagon) the ring toss style and the jigsaw style. The findings of this research were as follow : In term of children between 2-6 year old they like the covered colorful cloth of dust mite defending Fabric and they choose mostly the ring toss style followed by the printed cartoon of dust mite defending Fabric and the ring toss style. In term of parents group have never seen this product and they think that the using material is suitable. Besides they prefer the geometric style in vibrant colors for decorating the printing method and covered colorful cloth of dust mite defending fabric as well as the choosing product should realize the important health. Moreover they prefer very much the decoration of printed cartoon of dust mite defending fabric in the ring toss. In case of product they prefer the geometric about size style and suitability. In term of general interested people group have never seen this product and they think that the using material is suitable. Besides they prefer the jigsaw style in vibrant colors for decorating the printing method. Moreover they prefer the decoration of covered colorful cloth of dust mite defending fabric in the geometric style. In case of product they prefer the geometric about size style and suitability..

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Design and Product Development Ceramics Using for Making Wall of Energy Conservation Building
Design and Product Development Ceramics Using for Making Wall of Energy Conservation Building

This research aims to study and develop ceramics material using in the wall construction which can be used to proof the heat and water reduce absorbed humidity in the building. The product can save the energy especially the building which is set the air conditioning. The experiment found that the proportion of clay body can be developed and the result of thermal conductivity (K- value) was 0.111 W/ m. /K the permeability was 7 percent the glaze can be used to proof water. The product was compared to three kinds of construction materials which are brick concrete masonry unit and autoclaved aerated concrete found that K- value and permeability were lower. Moreover it can proof water and save more energy for the air conditioning building.

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