จำนวน Repository ( 3447 )

กรรมวิธีการปรับกรดของผักและสลักด้วยเครื่องปรับสภาพความเป็นกรดภายใต้การควบคุมอุณหภูมิและความดันบรรยากาศ
กรรมวิธีการปรับกรดของผักและสลักด้วยเครื่องปรับสภาพความเป็นกรดภายใต้การควบคุมอุณหภูมิและความดันบรรยากาศ

. This research aimed to study the acidification processes of carving vegetable using acid conditioning machine under emperature and pressure control which was developed in this study. Four acidification procedures were done at normal atmospheric pressure (method 1) under vacuum pressure for 10 (method 2) and 20 min (method 3) and vacuum pressure alternating with normal atmospheric pressure for each of 1 hour. There were two main parts of acid conditioning machine including the temperature controller inside the pickle tank and heat conductor tank and the pressure controller inside the pickle tank. The pickling temperature was stabled at 40oC under the pressure of 0.5 Bar. PLC (Programmable Logic Controller) program was used to write the ladder for controlling all processes and display through SCADA system. The results showed that the acidification method by soaking the carved-rose carrot under vacuum pressure alternating with normal atmospheric pressure showed the shortest time to equilibrium by 7 hours. Then the carved-rose carrot was packed in the glass jar followed by sterilized in boiling water for 15 minutes and stored at room temperature for 7 days. Total bacteria count Escherichia coli and Yeast-mold were not exceeded than the standard limit. Staphylococcus aureus was not detected throughout the storage periods

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ฤทธิ์ต้านอนุมูลอิสระของกุ่มบก
ฤทธิ์ต้านอนุมูลอิสระของกุ่มบก

The aim of this research was determine total phenolic content total flavonoid content and antioxidant activity by DPPH and ABTS assay from leaves flower and stem of Crateva adansonii DC. subsp. trifoliate (Roxb) Jacobs that was extracted by Soxhlet method using ethanol dichloromethane and ethyl acetate as solvent. Leaves extract showed the highest total phenolic content and antioxidant activity. Ethanolic leaf extract showed the highest total phenolic content (157.13±0.32 mg GAE/g extract) and antioxidant activity by DPPH assay (53.64±3.78% (IC50 = 1.49±0.02 mg/ml)) and ABTS assay (76.51±0.97% (IC50 = 0.84±0.01 mg/ml)).When we considering solvent effect found that ethanolic extract showed the highest total phenolic content and antioxidant activity. Total flavonoid content ethyl acetate extract showed the highest total flavonoid content. Total phenolic content significantly correlated with antioxidant activity.

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ผลกระทบและส่วนผสมที่เหมาะสมของผงเปลือกมังคุดสำหรับแบบหล่อทรายชื้น
ผลกระทบและส่วนผสมที่เหมาะสมของผงเปลือกมังคุดสำหรับแบบหล่อทรายชื้น

Metal casting with Green sand mold is essential for participation in the manufacturing industry that requires natural resources and chemicals as an element. This research studied the effects of the right mix of mangosteen shell powder on green sand mold. The objective is to study and analyze the mixture of moist sand formations consisting of natural sand bentonite mangosteen shell powder and water affecting the properties of green sand mold by experiment method. Starting from studying relevant information of natural materials that affect sand mold and planning experimental design by using the experimental design program for the trial version in the experimental design and analyze results. The results showed that mangosteen peel powder had an effect on the properties Compression strength and higher hardness of sand mold but does not increase the ability to release a lot of air permeability The optimum blend ratio was composed of 90% reused sand 7% bentonite 1% water and 2% mangosteen powder by weight air permeability. The hardness of the sand casting was 0.71 kg/cm2 47.36 and 94.06 Scale B respectively.

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กาวหลอมร้อนจากยางธรรมชาติ
กาวหลอมร้อนจากยางธรรมชาติ

The purpose of this research was to study hot-melt adhesives from natural rubber (Standard Thai Rubber 20 STR 20). In order to improve the adhesion and melting properties of hot-melt adhesive to get the best glue formula from STR 20 the ethylene vinyl acetate content (EVA) paraffin wax (Wax) and petroleum resin (Resin) were varied from 25 50 100 125 and 150 phr (Part Per Hundred Rubber). It was found that the best adhesive formulas consisted of 100 phr of STR 20 25 phr of wax 150 phr of EVA and 150 phr of resin. For preparing hot-melt adhesive first the wax was heated and maintained at 160-170 ºC then cut the STR 20 into small pieces and slowly added the rubber into the melted wax until the rubber was completely melted. And then added resin and EVA and cooled to room temperature finally the results show that hot-melt adhesive was dark brown hard and odorless smooth texture and easy to melt with 514±14 centipoises of Viscosity at 150 ºC 82.49±1.4 lbf/in2 of shear strength and 2.06±0.02 kN/m of cleavage peel strength.

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การศึกษาสมรรถนะของโรงไฟฟ้าไตรแลทเทอร์รัล ซับคริติคัล โออาร์ซี และซุปเปอร์คริติคัล โออาร์ซี โดยใช้แหล่งความร้อนใต้พิภพเป็นแหล่งพลังงาน
การศึกษาสมรรถนะของโรงไฟฟ้าไตรแลทเทอร์รัล ซับคริติคัล โออาร์ซี และซุปเปอร์คริติคัล โออาร์ซี โดยใช้แหล่งความร้อนใต้พิภพเป็นแหล่งพลังงาน

This study investigates three different types of power plant include a trilateral cycle (TLC) subcritical organic Rankine cycle (ORC) and supercritical ORC power plant driven by geothermal heat source with mass flow rate 1 kg/s and temperature of 100๐C 110๐C and 120๐C. with 27 substances were examined as the working fluid of the power plant. While the net power output of 4.78 kW and 7.74 kW is obtained from the subcritical ORC with RC318 as its working fluid when the heat source temperature are at 100๐C and 110๐C respectively. Meanwhile the net power output of 11.85 kW is obtained from the subcritical ORC with R227ea as its working fluid when the heat source temperature is at 120๐C. The net power output of 5.64 kW and 9.16 kW are obtained from the supercritical ORC with R218 as its working fluid when the heat source temperature are at 100๐C and 110๐C respectively. Meanwhile the net power output of 12.88 kW is obtained from the supercritical ORC with R143a as its working fluid when the heat source temperature is at 120๐C. Furthermore the net power output of 7.96 kW 12.27 kW and 17.38 kW are obtained from the TLC plant with heptane as its working fluid when the heat source temperature are at 100๐C 110๐C and 120๐C respectively.

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