In this study the wind speed characteristic and evaluation of wind power generation at Samoeng district Chiang Mai were investigated using wind speed data and wind direction data during time of January 2011 to December 2011 and measured at a height of 20 40 and 80 m above ground level. It was found that the mean wind speed of 3.8 3.92 and 4.30 m/s. While the mean wind direction of 20.73% and indicating from the southwest. The mean of power density of 107 W/m2 the shape parameter (k) was 1.715 1.633 and 1.783 scale parameter (c) of 3.649 3.651 and 4.092 m/s the mean of wind shear coefficient was 0.19. The evaluation of wind energy for electricity generation by install the wind turbine of Nordex N50 from Germany and Vestas V90 from Denmark were capacity of 800 kW and 3 MW. It could produce annual electricity of 1761379 kWh and 3772400 kWh and the capacity factor show 25.13% and 14.35% respectively. Finally the results showed the northern area of Thailand was suitable for wind power development in further.

This research was aimed to study of the effect of dragging force on paper cone falling by using the high-speed video analysis technique. Four different sizes of paper cones ranged from 3.00-5.70 centimeter were used. The cones having the same mass of 12 g and falling from 2.50 meters height were recorded for 240 frames per second and then were analyzed using the Tracker Video Analysis software. The results showed that (1) all four different sizes of paper cones were not freely fall with the Earths gravity due to indirect proportion with time of theirs speeds. The terminal speed of two large cones having diameter of 5.00 and 5.70 centimeters were 4.42±0.03 and 3.97±0.04 meters per second respectively. Only 0.87% of these experimental values were different from the theoretical ones. (2) The theoretical trajectory of these cones falling using the terminal speed from the experimental agrees with the theoretical ones. (3) The experimental drag force showed a second order function of the paper cone’s speed. The evaluated drag force during terminal area is approximately equal to the cone weight. Thus this technique can help students and teachers to visualize simple physics phenomena and relate them to the physics principles learnt in the classroom

Direct thermal decomposition mercury analysis is an efficient technique for determination of mercury in facial whitening creams. The analysis can be performed without any sample preparation. The samples can be weighed and placed directly into the analyzer. Thus there is no chemical waste produced in sample preparation. The time and energy used in sample digestion are saved as well. The calibration curve between mercury absorbance in terms of peak height and weight of standard mercury in the range of 0.1-10 ng was created. The calibration curve was linear followed the equation y=2.003x10-2X– 5.14x10-4 with coefficient of determination (R2) 0.9991. The precision in term of repeatability were 14% and 5.9% rsd (n=3) at 1.2 and 868 µg kg-1 respectively. The recoveries were between 88-110%. The detection limit (LOD) was 0.1 µg kg-1 (3sd/m n=10). The amount of mercury detected in 12 whitening cream samples sold in Chonburi province during the year 2019 were within the safety standard permitted in general cosmetics under the notification of the Ministry of Public except two samples were over the permitted standard.

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

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