จำนวน Repository ( 3447 )
การวิจัยเพื่อการพัฒนาปฏิบัติการเคมีวิเคราะห์ : การวิเคราะห์กึ่งจุลภาคเพื่อเป็นมิตรต่อสิ่งแวดล้อม
Analytical chemistry laboratory manual was developed for the student in the Division of Enviromental Science and Technology Faculty of Science and Technology Rajamangala University of Technology Phra Nakhon with the aim of promising the laboratory skill of the student in the preparation and standardize the solution gravimetric analysis volumetric analysis and finally spectroscopy analysis. Traditionally in the analytical laboratory pricey analytical grad of the reagent with large amounts and quantities is required. Moreover some of them are toxic and harmful to the environment. These can cause a problem for the university in which the budget is limited. In this work the idea of the small but powerful experiment was conducted. All the chemical and reagent was reduced to 50%. In the final laboratory instead of costly and toxic reagent some substances were replaced with the natural material such as water extraction from purple cabbage. According to the results the developed experiments were accurate enough for practicing the student except for the precipitation titration experiment. In order to evaluate the understanding a mini-project was assigned to the student in the group. By using the developed manual the student can overcome the problem in the lab and the awareness of the environment was also improved.
การศึกษาพฤกษเคมีและฤทธิ์ทางชีวภาพของสารสกัดจากมะพอกที่มีผลต่อการเจริญเติมโดของวัชพืชในนาข้าวเพื่อสนับสนุนการใช้ประโยชน์และเพิ่มมูลค่าความหลากหลายทางชีวภาพอย่างมั่นคงและยั่งยืน
This research aims to study phytochemicals and potential of Mapok (Parinari anamense Hance) extracts to inhibit germination and growth of Barnyard grass (Echinochloa crus-galli) a common weed in the rice fields. Organic solvents extracted the part of fruits barks and leaves of Mapok included hexane ethyl acetate and methanol. Crude extracts compose of fruit hexane extract fruit ethyl acetate extract fruit methanol extract bark hexane extract bark ethyl acetate extract bark methanol extract leaves hexane extract leaves ethyl acetate extract and leave methanol extract. Crude extracts were tested of phytochemical tested of germinating inhibition root length inhibition stem length inhibition and dry weight inhibition of Barnyard grass. Leaves ethyl acetate extract showed highest inhibit germination and growth of Barnyard grass The leave ethyl acetate extract was separated by column chromatography to yield nine fractions (F1 – F9 fraction) and tested inhibit germination and growth repeating. The results showed that 1. The crude ethyl acetate extracts from the bark of Mapok at a concentration of 3000 ppm showed the highest inhibited percentage of germinating inhibition root length inhibition stem length inhibition and dry weight inhibition. 2. Fraction F8 of leaves ethyl acetate extract showed the highest inhibited percentage of germinating inhibition root length inhibition stem length inhibition and dry weight inhibition.
คุณสมบัติเชิงกลของคอนกรีตมวลเบาผสมวัสดุปอซโซลาน
This research study the effect of pozzolanic materials on light weight concrete by replacement cement with fly ash and Meta kaolin which affect the properties of concrete by using pumics aggregate. Coarse in aerated concrete and consider mechanical properties. Aerated concrete replacement cement by fly ash 20% 35% and 50% respectively and meta-kaolin is replaced. From the results it was found that the compressive strength of light weight concrete at 28 days w/b = 0.55 was higher than that of every 14 days of cement and cement cement replacement by fly ash 50% highest value compressive strength. More than all the ingredients replaced with fly ash and Meta kaolin. When considering the flexural strength of replacement cement with 10% by Meta kaolin the maximum flexural strength of 80 ksc was higher than that of control concrete and all other ingradient. Experimental tensile strength at 28 days result found that replacement cement by fly ash at 35% gave the highest tensile strength of 28 ksc and gave higher tensile strength than all other ingradient. From the impact strength test at age 28 days it was found that the replacement cement 35% by fly ash gave the highest impact strength of 92.00 joule than the 20% and 50% respectively and higher impact strength than that of all kaolin. Except for control concrete.
การรับแรงกระแทกของคอนกรีตผสมปอซโซลานโดยระบบสามประสาน
This research study to the effect of pozzolanic materials by replacement cement by fly ash and Meta kaolin which affect the mechanical and physical properties of concrete. According to Standard test such as Compressive strength flexural strength and impact strength. The replacement cement by fly ash was 15% 30% and 45% respectively and replacement cement by meta-kaolin was 10% 15% and 20% respectively. The results showed that the compressive strength of concrete at 28 days. When considered ratio w/b = 0.40 was higher than w/b = 0.45 all ingredient. The replacement cement by fly ash was the most effective. 10% (375 ksc) 15% (362 ksc) and 20% (354 ksc) respectively. The replacement cement by meta-kaolin gave the highest flexural strength of 41 ksc higher than control mixed concrete and all other ingredient. At the age of 28 days The replacement cement by meta-kaolin was 10 percent result to the highest impact strength was 11 joule which was close to that of fly ash by 30 percent give value was 110 joules and more than replacement cement by meta-kaolin was 15% (100 joule) and 20% (95 joule). It can be concluded that the increase in meta-kaolin content result to compressive strength will reduce flexural strength and impact strength. As the amount of fly ash increased the compressive strength increased. flexural strength and impact strength Increased value.
การออกแบบและพัฒนาหุ่นทดสอบการชนรถจักรยานยนต์
The purpose of this research is to design and develop dummy (anthropometric test dummy) for motorcycle frontal collision test. The conceptual design of dummy is male aging between 25-55 years old 6 pieces of rib and deformable 76.2 mm. In order to performance test it was classified into 2 testing by static testing and dynamic testing. For static testing the energy absorption behavior between force and deflection or “ static curves” is determined. While dynamic testing is considered to the energy absorption behavior between forces and several velocities or dynamic forcedeformation curves impact acceleration impact force on sternum and injury severity with the relationship of viscous in velocity function. The results of the energy absorption behavior on chest of dummy from static testing the tendency of chest deflection is relatively low during the initial force and suddenly increasing when rise to the critical point. This behavior is similar to the energy absorption of the human chest. Therefore the design features of this test dummy can reflect behavior that is close to the human anatomy. In case of dynamic testing it is discovered the ability of the dummy testing to absorb up to 560 J impact acceleration 3 8 . 4 3 g impact force on sternum 5 . 0 9 4 kN. The viscous in velocity function is 0 . 8 2 5 m/ s which compared to injury severity at AIS3+ ( or higher than serious injury) . Therefore the dummy design in this research project corresponds to the collision test of a motorcycle.