จำนวน Repository ( 3611 )
กำลังอัดความสามารถเก็บกักคลอไรด์และสัมประสิทธ์การแพร่คลอไรด์ของคอนกรีตผสมเถ้าก้นเตาบดละเอียดและผงหินปูน
This research was aimed to study the compressive strength chloride binding capacity and chloride diffusion coefficient of concrete replaced by ground bottom ash (GBA) and limestone powder in ordinary Portland cement (OPC). The water to binder ratios were 0.55. The results showed that the compressive strength of concrete with GBA was lesser than that of OPC concrete at 28 days. Also the compressive strength of concrete with limestone powder was close to that of OPC concrete and compressive strength could develop of concrete with GBA 20% and 30% higher than that of OPC concrete at 56 days. Moreover the total chloride of the concrete containing GBA and limestone powder was less than that of OPC concrete. The chloride penetration of the concrete containing GBA and limestone powder was less than that of OPC concrete. The chloride binding capacity of the concrete made with ground bottom ash and limestone powder were higher than that of OPC concrete. Finally the chloride diffusion coefficient of the concrete containing GBA and limestone powder was less than that of OPC concrete.
ผลของอุณหภูมิที่มีต่อค่าความต้านทานและความจุไฟฟ้าของข้าวเปลือกที่มีความชื้นแตกต่างกัน
This research proposes an application of resistive and capacitive soil moisture sensors to investigate the influences of paddy temperature on the electrical signal received from sensors when tested with paddy moisture in the range 9.2 - 22.75%wb at 40 - 80ºC to determine the relationship between paddy moisture and electrical signals. It was found that the mean signal values between 20 - 40 seconds from both sensors were inversely linear correlation with the moisture content of the paddy. Temperature is the factors that influence the measured electrical signal. R2 Adjust R2 (95% confidence interval) and RMSEC showed that the model developed from the resistive sensor signals was accurate in calculating the moisture content of paddy between medium to high temperature in range 60 - 80ºC more than the low temperature range. While the capacitive sensor signals model is accurate in calculating paddy moisture between low to medium temperature in range 40 - 60 ºC. Therefore the resistive soil moisture sensor is possible and more suitable for applying as a paddy moisture sensor in the high temperature drying processes than a capacitor soil moisture sensor.
อิทธิพลของสภาวะการผลิตและการเก็บรักษาต่อสมบัติทางเคมีกายภาพของพริกป่นและพริกป่นคั่ว
Development of chili powder products through consumer survey to be used as the information for the development of high quality chili powder. The quality and physicochemical properties of chili powder during storage were investigated. The sound and red pods of fresh chili were washed and blanched at 100ºC for 3 min. Blanched chili pods were soaked in 0.25% sodium metabisulfite with 1.0% citric acid for 30 min prior to drying in a tray dryer at 65°C for 14 h to obtain dried chili with a final moisture content of approximately 8%. Dried chili pods without stem were ground to obtain chili powder. Roasting before grinding resulted in the reduction of moisture aw and color values. The results of study on the quality changes of chili powder during storage showed that storage temperature was the important factor affecting the changes in physicochemical properties and percentage of consumer acceptance. Meanwhile aluminum foil packaging slowed the increase of aflatoxin content in chili powder better than polypropylene. However aerobic bacterial count of the developed chili powder product is very low compared to the microbiological specifications while yeast and mold were not detected. The product contains a standard level of aflatoxin content after 12 weeks in all storage conditions which corresponds to the awareness of consumers in terms of quality cleanliness and safety are important factors in deciding to buy chili products.
การประเมินประสิทธิภาพเครื่องอัดลูกอมขิง
This research objective was to design the ginger candy compression machine and determine the efficiency and capacity for saving time and labor in pressing ginger candy for community enterprise groups Pim Malaherb Chiang Rai Province. Ginger candy compression machine consists of the main structure namely the extruder and power transmission systems. The machine was designed with two horsepower motors or 1.5 kilowatts to drive the shaft and to rotate the screw through the flange. This study installs the inverter to control the motor speed at 1000±10 1200±10 and 1400±10 rpm. The extrusion die had an average diameter of 9.7 millimeters. The results found that the motors speed that was suitable for compression was a Rotational speed of 1400±10 rpm. When the speed increased the efficiency and the working rate increased too. The amount of ginger stirred was used at 300 500 600 900 1000 1500 2000 and 3000 grams. The maximum efficiency was 90.85 percent. The efficiency increased with the amount of ginger stirred. The ginger candy compression machines engineering economic analysis results found that the machines operating cost was 18063.6 baht per year. When considering the machines operation at 792 hours per year the payback period was 6 months and 11 days.
การคัดเลือกแบคทีเรียจากลำไส้กุ้งกุลาดำเพื่อใช้เป็นโพรไบโอติกสำหรับการเพาะเลี้ยงสัตว์น้ำ
In this study 14 bacterial strains isolated from gastrointestinal tract of black tiger shrimp (Penaeus monodon) was investigated for their probiotic potential. The results showed that 6 strains namely S1 S3 S6 S7 T4 and T5 were able to degrade 3 nutrient substances including protein starch and lipid among which S3 S7 and S2 were the best tested nutrient-degrading bacteria respectively. Six bacterial strains were unable to lyse red blood cells including S2 S3 T0 T1 T2 and T3. S2 strain showed the strongest antibacterial activity against shrimp pathogenic Vibrio harveyi following an agar overlay technique. Based on environmental tolerance tests S2 and T0 strains grew well under wide ranges of environmental conditions e.g. sodium chloride concentration (0-8%) pH (6-10) and temperature (25-37C). As a consequence S2 strain had the most probiotic potential for shrimp culture owing to no hemolysis of red blood cells inhibition of V. harveyi growth protein and lipid degrading ability and high environmental tolerance for shrimp cultivation. The strain was identified as Micrococcus sp. S2. However additional study focused on immune response nutrient digestibility and growth promotion of the strain should be further performed in marine shrimp.