The reduction of calcium carbonate (CaCO3) particle was prepared by wet grinding method with 40% dispersion. The particle sizes of CaCO3 were studied with various time of wet grinding. It was found that the particle sizes of CaCO3 rapidly decreased in 3 day of grinding after that it was slightly reduce. Therefore the CaCO3 at various time of wet grinding were mixed with concentrate latex (60% dry rubber content DRC). The result showed that the wet grinding for 2 days provided the superior machanical properties. In addition the compound with epoxidized natural rubber (ENR) as a coupling agent was investigated. It was found that the 5 phr of 30% mole percent of ENR results in significantly improved mechanical properties of the rubber vulcanizates.

The main objective of the study is to design blades for chopping heart rice straw. This study is composed of three main testing parameters. The first parameter used is speeds at which the knife blades that will chop the straw. They will have 2 speeds one at 540 and the other at 720 rpm. The second parameter is the types of blades that will be used eclipse blades and smooth blades. The last parameter is the cutting edges. The eclipse and smooth types of the blades will have 4 5 and 6 cutting edges. For this test we use stubble sorted 50 heart rice straws. Placing the straw on the prepared steel and test with all three testing parameters repeating each testing parameter thrice and record the results. Based on the testing and evaluation the 6 edge eclipse blades with a speed of 720 rpm. Yielded the highes results for chopping heart rice straw at 66 percent. For the 6 edged smooth blades with a speed of 720 rpm the yield results for chopping heart rice straw was at 35.76%

This research aimed to compare the techniques and method used to solve non-linear equations with SEM. By Partial Least Squares (PLS) technique and Product Indicator Approaches (PIA) technique. Were tested by the two methods of case studies is motive in the decision to study at Bachelor degree in Rajamangala University of Technology Suvarnabhumi Suphanburi campus Information Technology field. For sampling 221 found Partial Least Squares (PLS) technique to solve the problem of non-linear equation. However the same study Product Indicator Approaches (PIA) technique do not use this method as error indicators for the model with a negative value wrong predictions by SEM. Can not be predicted by the model to them.

This research was aimed to study the effect of bottom ash (BA) as fine aggregate in fly ash concrete and cement-only concrete on strength of water-cured and uncured concrete. The water to binder ratios were 0.35 and 0.55 to represent high strength and normal strength concrete respectively. The weight percentages of replacement of cement by fly ash were 0 and 30%. The replacement ratios of bottom ash as fine aggregate were 0 10 and 30% by volume of fine aggregate. The results indicated that the slump and setting time of concrete increased with the increase of bottom ash content. In contrast the compressive and tensile strength decreased with the increase of bottom ash content. From the curing sensitivity index it was showed that the fly ash concrete required longer curing period than cement-only concrete. In case of high strength concrete the use of bottom ash in fly ash concrete can reduce curing sensitivity of concrete

The sensitivity analysis in efficiency of solar water heater system self-circulated by a stream power was performed in this study. The mathematical model of the system was developed based on the experimental results to predict the available amount of water pumped temperature and pressure in main devices. This system was operated by using a simple flat plate solar collector with an exposed area of 1.58 m2 and a storage tank of 30 liters. The results of systematic performance which performed by math model was compared to the experimental results. It was found that the values of were 5.876% 3.583% and 1.361% for vapor pressure and temperature in the flat plate solar collector and temperature in the storage tank respectively. The system was workable when the solar energy input values were equal to or greater than 584 W/m2 607 W/m2 632 W/m2 and 662 W/m2 for discharge head 1 m 1.5 m 2 m and 2.5 m respectively. From system simulation the system could have the daily average thermal efficiency was between 2.94 – 11.47% and the daily average pump efficiency 0.00057 – 0.0026% depending on the intensity of incident solar radiation and the discharge head of the system.