Pengaruh Daya Penyinaran Gelombang Mikro Terhadap Karakteristik Pembakaran Droplet Minyak Jarak Pagar

The objective this research is to investigate the effect of microwave irradiation power on the combustion characteristics of Jatropha curcas oil. Jatropha Curcas oil is one of alternative fuel. Some advantages of this oil are environmentally friendly, not included in food which can be consumed and renewable. But it can not be use directly because it has a long chemical chain with several double bonds and the viscosity and flash point are very high. One method to improve the combustion characteristics of Jatropha curcas oil, is to irradiate this oil with microwaves. This is due to the energy of microwaves can be absorbed by water, fats and sugars that can affect the Jathropa Curcas oil. The microwave frequency used is 2.45 GHz. Microwave irradiation power is given to the jatropha oil are 119 watt, 252 watt, 385 watt, 539 watt and 700 watt, and the time given 15 minute. And droplet diameter used is 1.5 - 2 mm. From this research was found that microwave can change the viscosity, visualization and dimension of the flame, increase the burning rate, percentage of microexplosion, accelerate the appearance and prolong the duration of microexplosion

Pengaruh Kadar Vitamin E Dalam Pakan Terhadap Kualitas Telur Ikan Patin (Pangasius Hypophthalmus) [Effect of Dietary Vitamin E on the Egg Quality of Catfish (Pangasius Hypophthalmus)]

Percobaan ini dilakukan untuk menentukan pengaruh dari vitamin E (VE) dalam pakan induk ikan patin, Pangasius hypophthalmus terhadap kualitas telurnya. Empat macam pakan yang digunakan yaitu yang mengandung protein relatif sama yaitu berkisar antara 37.68-38.05% dan kalorinya 3066.66-3104.71 kkal/kg pakan, kandungan VE yang digunakan dalam pakan secara berturut-turut antara lain 28.08, 146.55, 189.65, dan 251.80 mg VE/kg pakan. Induk dipelihara dalam jaring yang ditempatkan dalam kolam beton. Setiap liari ikan diberi makan sebanyak 4% dari berat tubuh untuk selama 15 bulan. Selama periode pemberian pakan, tingkat kematangan gonad diperiksa, dan pembuahan dilakukan secara buatan. Vitamin E dan kandungan lemak dalam telur yang dihasilkan meningkat sesuai dengan peningkatan dosis VE dalam pakan. Vitamin E mempengaruhi gonad somatik indek, fekunditas, diameter telur, laju penetasan, larva abnormal, dan jumlah total larva yang dihasilkan. Pakan yang mengandung 189.65 mg VE/kg pakan menghasilkan tingkat penetasan yang tinggi (78.77%), jumlah total larva 332,339 ekor/kg induk, dan larva abnormal terendah (0.19%). Penambahan 189.65 mg/kg pakan dapat meningkatkan kualitas telur ikan patin

Karakteristik Pembakaran CH4 Dengan Penambahan Co2 Pada Model Helle- Shaw Cell Pada Penyalaan Bawah

Along with the development of industrial technologies is rapidly increasing the demand for renewable energy sources becomes a very important consideration. One of the alternative energy is now being developed is the energy derived from organic materials, this is because the organic compounds are classified as renewable energy. One energy technology in accordance with the requirements of the biogas technology. If biogas is purified or cleaned of impurities in this case CO2 is good, he would have the same characteristics as natural gas. How big is the influence of CO2 on heating value (heat) in the combustion process it is necessary to an investigation. one by looking at the characteristics of combustion, both the pattern and pace of rambatnya. Combustor used in this study is a model of Helle-shaw cell measuring 50 x 20 x 1 cm. Variation of the mixture used is the ratio 7,5:1 to 10: 1 with the addition of 10% 20%, 30% CO2. Performed on the ignition of ignition. Observation of the shape and rate of flame propagation is done using a high speed camera. The results showed that the ratio of 7,5:1 to 10: 1 blue color of the flame and the flame propagation speed greater penembahan but with 10% CO2 20%, 30% color changing flame reddish yellow which indicates incomplete combustion occurs, and the smaller the rate of flame propagation. This is influenced by the presence of buoyancy forces generated by the combustion

Superheated Microdrops as Cold Dark Matter Detectors

It is shown that under realistic background considerations, an improvement in Cold Dark Matter sensitivity of several orders of magnitude is expected from a detector based on superheated liquid droplets. Such devices are totally insensitive to minimum ionizing radiation while responsive to nuclear recoils of energies ~ few keV. They operate on the same principle as the bubble chamber, but offer unattended, continuous, and safe operation at room temperature and atmospheric pressure.Comment: 15 pgs, 4 figures include