泰國

The purpose of this project is to control the Aphis craccivora Koch. on the cow pea Vigna unguiculata (L.) by using two predators, the earwigs (black) beetle, Proeus simulans Stallan and the ladybird beetle, Micraspis discolor (F.). The experiments were carried out in the closed system in the laboratory and in the opened field with various ages of Proeus simulans Stallan and Micraspis discolor (F.) from the 1st - 4th stage of embryo to the adult form. Prior to the study in the field, the capability of the predators, Proeus simulans Stallan and Micraspis discolor (F.), that can eat the Aphis craccivora Koch. within a period of time was set up in the laboratory. The result showed that the 1st-4th stage of embryo of Micraspis discolor (F.) can eat 8.46+1.25 – 12.50+0.60, at 95% confidence, Aphis craccivora Koch. per day, while its adult can eat at the average number of 43.66 + 0.78, at 95% confidence, per day. The 1st–3rd stage of Proeus simulans Stallan embryo and the adult form can eat Aphis craccivora Koch. at the average number of 2.37+0.33 – 3.74+0.29 and 9.84+0.36, at 95% confidence, per day, respectively. This data showed that Micraspis discolor (F.) was more efficiency as predator than Proeus simulans Stallan. The insecticide activity of these two predators in the closed field (8 m x 9 m) was then determined. The number of Aphis craccivora Koch. on the plant was randomly counted everyweek for 10 weeks. It was found that the number of Aphis on the experimented and control groups were 16.20+4.30 and 2,582.00+102.40, at 95% confidence, per plant, respectively. The result support the efficiency of the two predators in controlling the pest. When the experiment was set up at the two opened field (6 m x 30 m, each field), 27.51+2.74 and 52.11+5.21, at 95% confidence, of Aphis craccivora Koch. were found on the plant of experimented and control groups, respectively, at the 10th week. The lower number of Aphis on the control plant might possilbly due to the interference from natural predators. From this study, the biological control of Aphis craccivora Koch. on the cow pea Vigna unguiculata (L.) could be achieved by using Proeus simulans Stallan and Micraspis discolor (F.). To avoid the use of chemical insecticides, biological control should be trained to farmers to help reduce the environmental problem.

The purpose of this project was to create a detection device for alcoholic drunk condition in human by using the principle of vapor pressure difference between breath samplings from normal and alcoholic-drunk men. The work comprises of three major steps. The first task was an experiment to determine an average air volume that can be fully blown out from the lungs of non-drunk people as a control. Twenty adult Thai volunteers weighing between 50 - 80 kg (average 59 kg) were used. The average blown out air volume was found to be 369.9 mL, with the range in values from 340-400 mL (sample size N = 20, SD = 15.47). The second task was an experiment to measure relationship between the blown air volume (100-700 mL, both from alcoholic-drunk and control groups of people) and the resulted vapor pressure by using manometer. The vapor pressure of normal breath increased from 400 to 1,600 newton/m2 with increasing blown air volume, whereas that of the alcoholic-drunk was found to be 600 to 1,800 newton/m2. The last task was to create a detection device prototype to gauge the alcoholic content in the human body from the breath. Air volume of 300 mL was arbitrary chosen to trigger lighting up of indicator lamps. The breath samples of low vapor pressure (low amount of alcohol, 21.12-44.00 mL, equivalent to 14.00-29.17 mg%) would trigger a green lamp to light up. A moderate vapor pressure range (medium amount of alcohol, 88-132 mL, equivalent to 58.33-87.57 mg%) would trigger green and yellow lamps to light up while a high vapor pressure (high amount of alcohol, 250 mL, equivalent to 165.72 mg%) would trigger green, yellow and red lamps to all light up. None of the three lamps would light up from (non-alcoholic) breath of control people. This device has also been tested to external group of volunteers. The work in this project has successfully demonstrated a useful application of simple principle in chemistry on partial vapor pressure.

The objectives of this study were to investigate (1) the floral biology of Jatropha curcas Linn. as well as its possible pollinators, (2) the correlation between the number of pollen on stigma and the frequency of floral visitors, (3) the attractiveness of essential oil extracts from three species of Lamiaceae, i.e. Hyptis suaveolens, Plectranthus ambonicus and Orthosiphon aristatus, to Apis florae, (4) the repellent effect of crude extracts from three species of Graminae, i.e. Imperata cylindrica, Eleusine indica and Dactyloctenium aegyptium, on Polyphagotarsonemus latus, and (5) the effect of appropriate combination between lamiacean essential oil and graminaceous crude extract on the percentage of fruit setting and insect pest protection. \r Jatropha curcas is monoecious plants with tiny male and female flowers borne on the same paniculate cyme. One plant produces 15-30 inflorescence. Each inflorescence composes of 70-120 florets, and only 4-8 florets are successfully setting fruits. Each flower takes approximately 17 days in developing from floral bud till floral opening. The appropriate time for pollination is from 09.00 am to 10.00 am. While bees, wasps, hornets, flies and dragonflies are its potential pollinators, mites, aphids and worms are its harmful insect pests. \r Three volumetric, 1, 3, 6 and 9 ml, of each essential oil extracts were separately sprayed on each observed inflorescence. According to the experiment, 6 and 9 ml of each of the essential oil extracts give similar effective outcome, However, The H. suaveolens extract at 6 ml is the most effective attractant for A. florae. because it uses less of the oil extracts.\r Four concentrations, 0.1 %, 0.5 %, 1.0 %, 1.5 % and 2.0 % of each of the crude extracts from three graminaceous plants were sprayed on each tested plants separately. Concentations above 1.0% consistently provided an effective biocidal activity against Imperata cylindrica , however 1.0% is accecptable. because it uses a reduced level of the crude extracts\r The combination of H. suaveolens’s essential oil and I. cylindrica crude extract both significantly enhanced fruit setting of J. curcas and protected the plant from Polyphagotarsonemus latus without adverse effect on its pollinators.

This scientific research project “Tharn Din - Alternative Energy Source of the Future” is directed toward producing a new type of soil charcoal. Tharn Din, with excellent combustibility. The experiments were divided into six steps. First, we selected soils of exceptional adhesion property Next, we looked into many different combustible materials for soil admixtures. Many different formulas of soils and admixtures were tested. The most promising formulas were then optimized for maximum combustibility. After which, the best formula was chosen and we further optimized its combustibility. Combustion and ignition rate and characteristics of this formula were investigated. And lastly the effect of surface area on combustible rate was examined. It was found that mud was the best adhesive and wood chip was the best admixture. Tharn Din made of one part of mud and 3 parts of wood chips released higher thermal energy than normal charcoals. We found that a special type of Thai soil, Din See-eaw, when mixed with wood chips created Tharn Din of exceptional combustibi1it Ignition and combustible rates are proportional to the surface area of Tharn Din.

The highly water-absorbing polymers were prepared by the reaction of acrylic acid as a graft\r monomer and natural starch (eg. rice starch, sticky rice starch or corn starch) as the backbone\r using water hydrogen peroxide and vitamin C as solvent, initiator and catalyst, respectively. The\r reaction was carried out by mixing of starch in distilling water and stirring at 60-70 ℃ for 3\r hours and then cooled to 30℃ Acrylic acid was added and the pH was adjusted to 6-9 by the\r addition of limestone powder. To the stirred mixture were then added hydrogen peroxide (30%\r v/v) and vitamin C and continued stirring for 3 hours until the solution became viscous The\r viscous solution was neutralized with potassium hydroxide (30%v/v) to give the pH for 6.5-7\r and allowed to cool to room temperature overnight. The resulting solution was spread on\r winnowing baskets and allowed to dry under the sun to yield a continuous absorbent polymer\r film. The absorbent polymer film was ground and yield of white powder, The above procedure\r was repeated by using another types of starch. The ability of starch slurry to swell on heating, by\r absorption of water, is it’s most important practical property. Rice starch has very low swelling\r capacity in aqueous media compare with sticky rice starch and corn starch. The capacities of\r water-absorbing polymer were tested by placing polymer powder in the beaker and adding of\r water until it swell and cannot absorb more water. The polymers were found to be an excellent\r water absorbent, which absorbed water about 248, 245 and 167 times in weight of polymer for\r corn starch, sticky rice starch and rice starch, respectively. The water retention was calculated by\r measuring the amount of water releasing after every week for 10 weeks. They have also good\r water retention capacity. The swollen polymers were mixed with soil in ratio 1:3 and the\r increasing water holding capacity of soils which promotes more efficient plant growth in pot were\r test. It was found that the soil could be absorbed water for 10 weeks. It is possible to use highly\r water-absorbing polymers from natural starch in agriculture because they are low in cost and the\r polysaccharide main portion of the product is biodegradable

This project aimed to create a simple model of coin sorter with cheaper price, electricity saving using recycled materials for use in place of manual separation and compatible to the automatic coin sorters commercially available in the market. The principle applied in inventing this device was the gravity force that pushed coins to fall through its upper compartment to the lower part via a slope that determines the coin path as well as the speed of the coins. The upper part of the box was designed to control the rate of the descending coins and transported the coins to the separation section in single file order to prevent jamming. The lower part of the box consisted of the coin sorting mechanism which conveyed the coins to their assigned compartment according to coin diameters. The box could separate three kinds of Thai coins, 1,5 and 10 baht, with 95-98 % accuracy. The efficiency was in the range 150-250 coins per minute with highest accuracy at 150 coins per minute. The box was made from acrylics. The designed box can separate coins faster than manual sorting although not with as high efficiency as automatic machines which can sort up to 500 coins per minutes. At the present stage, it can not count the number of coins. However, it can be built at cheaper cost, does not require electricity or electronic devices and is suitable for small and medium size business. We aim to improve the box to give higher accuracy with coin counting ability.

The Red Palm Weevil is a kind of pest commonly found in all coconut and palm growing areas, causing considerable damage to palm trees. The pest at larva stage was found to be a popular food dish for both local people and visitors and has been commercially bred for consumption. This project aimed to develop a farming method to increase the quantity of red palm weevil larvae for commercial use, instead of the natural farming which fed the insects on rare natural materials. Firstly, the most appropriate food formula to boost the multiplication of red palm weevil using local raw materials was determined. Four food formula were developed: 1.combination of palm leaves, coconut fibers, and pig food, 2.palm leaves, coconut fibers, and rice bran,3. palm leaves, coconut fibers and cassava,4. a combination of crushed palm leaves and coconut fibers. The mixture ration were 1:1:1 for formula1-3 and 1:1 for formula 4. Equal number of the adult weevils were raised in the different food formula, the length and weight of the larvae obtained were measured every week for seven weeks. The gross weights and the effectiveness of the red palm weevil farming were analyzed using the feed conversion ratio (fcr), the daily growth rate, and the percentage increase in weight. It was found that. the weevils raised with food formula 1 yielded the larvae which grew the fastest with highest effectiveness. The most appropriate ratio of the food mix which yielded the satisfactory larvae size was determined to be 1:1:1 3.Next, experiment was carried out to improve the quality of the insect larvae for consumption. The larvae produced had some distinct smell which some consumers do not like.To improve the smell, the larvae were fed with the selected food mix added with minced fresh Pandanus leaves 2 days prior to consumption. Food mix with coconut fibers instead of Pandanus were used as control. Consumers were most satisfied with the larvae fed with added Pandanus leaves. Analysis of the food mix, larvae and Pandanus leaves found the common compound, Coumarins. In conclusion, our project found a suitable system of red palm weevil farming an alternative to conventional method which farmed the pest on cut palm trees. The new method resulted in the best yield of insect larvae with the highest consumer satisfaction and reduce destroying natural resource.

After short period of storage the coconut oil at room temperature we found that it becomes rancid. The oxidizing flavor is disgusting and causes economic loss. Some chemicals are used to prevent the oxidation of coconut oil but they are expensive and may be harmful to consumer’s health if used daily. Moreover, they are not suitable for homemade coconut oil and residual waste from the process may be environmental toxic. The present work thus aims at extracting substances from local plants and used as antioxidant for coconut oil. Seven kinds of local Caesalpiniaceae plants in Eastern Thailand namely Tamarind (Tamaridus indica L.), Peacock flower Caesalpinia pulcherrima L.), Flame tree (Delonix regia L.), Golden shower (Cassia fistula L.), Siamese cassia (C. siamea Lamk.), Candelabra bush (C. occidentalis L.), and Copper pod (Peltophorum pterocarpum DC.) were used. Ten grams of seed coats were mixed with 50 ml of the distilled water and 95% Ethyl alcohol (1:1) mixture in a closed container. The mixture was heated in a water-bath at 60 ℃ for about 2 hrs. and then kept in 10 ℃ icebox about 2 hrs. The mixture was then filtered and the filtrate was heated in an hot-air oven at 80 ℃ for about ? hrs. Ten ml of coconut oil was added with 0.5g of the extracts and kept at room temperature for 5 days. The pH and peroxide value (using the Iodometric titration method) of the oil were measured. It was found that the coconut oil with the Tamarind seed extract had the lowest peroxide value and was selected. Next the suitable amount of the Tamarind extract was studied by adding the extract to 10 ml coconut oil at 0-7% (w/v) and the contents were kept at room temperature for 5 days. The result showed that the 3% (and more over) Tamarind extract had the lowest peroxide value. Then the coconut oil with 3% Tamarind extract was kept at room temperature for 30 days. The pH and peroxide value were measured every 5 days. It was found that the oil could be stored for 25 days without significant change in pH and its peroxide value was less than 10 milliequivale n t oxygen per kilogram oil according to FAO/WHO (Codex) standard .Therefore, Tamarind seed coat at 3% could be used to retard the coconut oil oxidation for 25 days. This work presents the applicable use of plentiful local plants such as Tamarind seed, which is normally discarded, as an antioxidant for coconut oil.

Vacuum packaging is a packaging technique intended to extend the shelf life of food via the removal of air from an enclosed package prior to sealing. This process limits the growth of aerobic bacteria or fungi due to oxygen deprivation. In this work, we present a novel do-it-yourself vacuum packaging device using the exchange of water and air between two bottles to continuously generate a vacuum-suction effect. The sizes of bottle and vacuum bag were investigated for its impact on the vacuum generation in a plastic bag containing smoked fish sausages. Large commercial 3.1-litre PET bottle generated more vacuum than the smaller ones. An equilibrated vacuum pressure of a smaller plastic bag was lower than that of a larger size. With 3.1-litre PET bottles, the vacuum pressure for 3”x5”, 5”x8” and 6”x9” bags was equilibrated at 8, 10, 18 mmHg, respectively. Sausages packaged by our device last for 14 days when they were kept in -20oC refrigerator, which was comparable to those packed by the commercial vacuum packaging system for household use. This project demonstrates an application of simple science in a real life situation as well as a promotion of environmental protection idea as the electricity is not used in the vacuum generation process and the disposed plastic bottles can be reused.