จำนวน Repository ( 1574 )

การตรึงอะโซโตแบคเตอร์แบคทีเรียตรึงไนโตรเจนในอากาศด้วยวัสดุธรรมชาติและผลต่อการเจริญเติบโตของผักกวางตุ้งในดิน
การตรึงอะโซโตแบคเตอร์แบคทีเรียตรึงไนโตรเจนในอากาศด้วยวัสดุธรรมชาติและผลต่อการเจริญเติบโตของผักกวางตุ้งในดิน

Nitrogen is an essential nutrient for plant growth. When the plants have been grown for a long-term effect to decreased nitrogen in soil and insufficiency of the plant growth. One biological method for increasing the nitrogen content in soil is utilize of free nitrogen-fixing bacteria Azotobacter. Therefore the objective of this research was to search natural material suitable for Azotobacter fixation. The 10 natural materials were observed physical structure and investigated the ability of natural materials for Azotobacter fixation. The results showed that water hyacinth and bagasse stalks were fixed the Azotobacter of 2.43x108 and 1.94 x108 CFU per gram of each natural material respectively. After that the selected fixed Azotobacter of water hyacinth and bagasse stalks were studied the growth of Brassica Chinensis. This experiment was designed to 4 treatments. The first treatment was mixed of water hyacinth stalks and the Azotobacter. Second treatment was mixed of bagasse stalks and the Azotobacter. The third treatment was the Azotobacter only. The last treatment was soil only. The results indicated that the average of plant growth include height leaf number root length fresh weight and dry weight of the mixed of water hyacinth stalks and the Azotobacter had significantly higher growth rates than other treatments. The total nitrogen was also increased 1.4 fold in the soil. All results suggest that the water hyacinth stalk is alternative for the fixation of the free nitrogen-fixing bacteria Azotobacter as induce nitrogen in the soil and plant growth promotion.

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การวิเคราะห์โครงการผลิตหมึกพิมพ์รองพื้นสีขาวฐานตัวทำละลายสำหรับผลิตบรรจุภัณฑ์อ่อนตัว
การวิเคราะห์โครงการผลิตหมึกพิมพ์รองพื้นสีขาวฐานตัวทำละลายสำหรับผลิตบรรจุภัณฑ์อ่อนตัว

The research proposes to find an optimum ratio of solvent based white ink for flexible package development by studying and comparing the qualification of white ink on plastic film. The process consists of separating the white ink ratio into 5 sampling group ratios and then examining ink quality by its’ solid content and grinding. The viscosity is controlled in 16 second and then measured by Zahn’s cup no. 3. The sampling ink is printed and inspected printing quality by (1) E*ab and opacity on polyethylene terephthalate (PET) plastic film and oriented polypropylene (OPP) and (2) bond strength by extrusion. The result shows that sampling ink with hardener substances and ink and varnish ratio is at 90:10 certifies in all aspects compare with other sample. Indicators are the net present value (NPV) Benefit/Cost Ratio: B/C Ratio Pay Back Period and internal rate of return of investment (IRR). The Feasibility Study found that the projects are the net present value (NPV) of 5053593 baht payback period of 1 year 8 month and rate of return on investment (IRR) was 54.79 %. B/C ratio = 1.25

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ลักษณะรูปแบบหัวพ่นอะตอมไมซ์ในกระบวนการอะตอมไมเซชันด้วยก๊าซ
ลักษณะรูปแบบหัวพ่นอะตอมไมซ์ในกระบวนการอะตอมไมเซชันด้วยก๊าซ

This research article aims to study of the atomizer nozzle pattern in the gas atomization process. The production of metal powder by using a gas atomization process. It is the most popular process. This process is used in various industry and engineering application. However there is lack of information on the production of various precious metal powders in the jewelry manufacturing industry both in the country and abroad. For this reasons the research team is interested in applying this process for the Thai jewelry manufacturing industry. Currently the jewelry industry is in a transitional period of manufacturing technology with an increased focus on powder metallurgy technology. The production of metal powder by using a gas atomization process consisting of the following 3 steps: melting making of atomized molten metal cooling and solidifying for solid particles under a controlled gas atmosphere. Factors affecting particle shape particle size and particle size distribution are consisting of inert gas type molten metal temperature and the configuration or pattern of the nozzle that are different characteristics. The results can be concluded that Close-Coupled Nozzle is the most suitable nozzle for production due to the highest productivity providing the smallest particle size and spherical granular shape. The information from this study will be useful for the Thai jewelry manufacturing industry.

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การประยุกต์ใช้หม้อแปลงฟลายแบคสำเร็จรูปสำหรับแหล่งจ่ายไฟฟ้าแรงดันสูงความถี่สูง
การประยุกต์ใช้หม้อแปลงฟลายแบคสำเร็จรูปสำหรับแหล่งจ่ายไฟฟ้าแรงดันสูงความถี่สูง

In this article the construction of a high-frequency high-voltage commercial flyback transformer to supply an input voltage for a tesla transformer is proposed. The purpose of a demonstration is a breakdown through the air gap of electrode. To confirm the proposed method the design of control of a flyback converter by using a commercial flyback transformer is rated with a 10 to 15 kV output voltage to supply a tesla transformer at a rated 30 kV and 120 kHz. The experimental results of an output breakdown design of the electrode and the setting for a 1 cm space are constructed. The electrodes consisted of the following: sphere–sphere electrode plane–plane electrode sphere–plane electrode and rod–plane electrode. It was found that there was a breakdown at the output electrode in all cases. Accordingly there was a breakdown with a 2 cm sphere diameter with reference to the IEC 60052-2002 standard; after that it was compared with the standard table and the atmospheric and temperature at the laboratory were adjusted resulting to a high voltage equal to 31.5 kV.

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การวิเคราะห์ปริมาณสารสำคัญและฤทธิ์ต้านอนุมูลอิสระของสารสกัดใบกะเปียดเครือ
การวิเคราะห์ปริมาณสารสำคัญและฤทธิ์ต้านอนุมูลอิสระของสารสกัดใบกะเปียดเครือ

Premna trichostoma Miq. (Lamiaceae) mainly distribute in Asia including Thailand. Folk healers use this plant to treat fever as a juice splash and bathe. The aims of this study are to evaluate the quantity of active constituents and antioxidant activity of P. trichostoma leaf extract. Total phenolic compounds were determined using Folin-Ciocalteu method. Total flavonoid contents were determined by Aluminum chloride method. The amount of apigenin and kaempferol contents were analyzed by high performance liquid chromatography (HPLC). In addition the antioxidant activity was evaluated by DPPH and ABTS assay. The results showed that total phenolic contents total flavonoid contents and the amount of apigenin and kaempferol of P. trichostoma leaf extract was 46.45±15.30 mg GAE/g extract 25.48±2.02 mg CE/g extract 11.16±0.04 and 4.54±0.08 µg/g extract respectively. The IC50 values from the DPPH and ABTS assay was 117.50±1.22 and 36.14±1.53 µg/ml respectively. This study shows the antioxidant properties and active constituents of P. trichostoma leaf extract which indicates the potentials for further development of this plant

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