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Ozone production using DBDP technology used pulse high voltage to generate ozone. The duty cycle has been used the variations of 10%, 30%, 50%, 60% of the 350 Hz as installed frequency. The DBDP reactor constructed by using cylinder-cylindrical electrode configuration. The inner electrode was made by stainless steel mesh with a length of 19 cm, and the outer electrode was aluminum foil with a length of 19 cm. The barrier was made of tube pyrex glass. Ozone is generated utilizing air as an oxygen-containing gas source with atmospheric pressure and a flow rate of 10 L/minute. The results show that using 10% of the duty cycle produces a maximum output voltage of 5 kV, the resulting ozone concentration of 67 ppm. The 30% cycle produces a maximum output voltage of 7.7 kV and ozone production with a concentration of 115.2 ppm. The 50% duty cycle produces a maximum output voltage of 10 kV with an ozone concentration of 134.4 ppm. The 60% duty cycle is capable of generating a maximum output voltage of 10.77 kV with an ozone concentration generated from 160.8 ppm. We found that using 60% duty cycle is capable of producing high concentrations and ozone capacity.

Research on the distribution of ozone in a cold storage has been done. This cold storage is equipped with an ozone piping system. Ozone inserts to the cold storage was generated by dielectric barrier discharge plasma. The reactor is made of two stainless steel mesh wire cylindrical electrodes and a barried by a pyrex tube. The pipes are hollowed so that ozone can be distributed into cold storage. The distribution of ozone in cold storage is determined by placing a petri dish in twenty-four different points. Ozone that inserted to storage (10 cubic meters) with a capacity of 40 grams/hour. The inserting of ozone into cold storage was done with four different lengths of time wich are 30, 60, 90, and 120 minutes. Ozone distribution in storage was almost the same at each measurement points. The most influential in the distribution is the time. We found that the distribution of ozone into storage with average ozone concentration of 4.3, 6.3, 4.6, and 4.0 ppm with time 30, 60, 90, 120 minutes respectively. Futhermore, we also dissolve the ozone into the water in the tank in the same storage with temperature (2-8)0C. We found that the concentration of dissolved ozone in the water without samples was always greater than that of the existing fish and shrimp samples, with various dissolution times between (30-120) minutes at 30 minutes intervals. Cold storage dedicated ozone was used to store fish used to store tuna, milkfish and shrimp. With ozone immersion of fish in ozone-soluble water can maintain fish quality for 16 days.

Abstrak. Hama ulat grayak (S. litura) merupakan salah satu hama yang menyebabkan daun berlubang tidak beraturan, sehingga mengganggu proses fotosintesis sehingga mengurangi produksi tanaman cabai sehingga perlu dilakukan penanganan hama. Tujuan dari penelitian untuk melihat perbandingan efektivitas B. thuringiensis dengan teknologi ozon yang dibangkitkan melalui reaktor Dielectric Barier Discharge Plasma dalam mengendalikan S. litura pada daun cabai di laboratorium.Metode penelitian terdiri dari beberapa tahapan yaitu (1) Pemeliharaan larva S. litura (2) Perlakuan dan Pengujian Ozon terhadap S. litura (3) Pengujian Toksisitas Isolat Bt terhadap S. litura. Parameter penelitian ini tentang mortalitas (%), dan perubahan persentase populasi (%). Perlakuan pemberian Bacillus thuringiensis sangat efektif dalam mengendalikan Spodoptera litura, hal ini terlihat pada 1 hari setelah aplikasi (HSA) sudah tampak hama ulat yang mortalitas (kematian), sedangkan perlakuan ozon mortalitas S. litura baru tampak pada 3 hari setelah aplikasi (HSA).  Hasil penurunan jumlah hama S. litura pada aplikasi bakteri B. thuringiensis lebih cepat di hari ke 4 hari setelah aplikasi (HSA) yaitu 0 persentase ulat yang hidup, sedangkan perlakuan ozon sampai hari ke 10 HSA masih tersisa 20 % hama S. litura.Comparison of the Effectiveness of Bacillus thuringiensis with Ozone Technology in Spodoptera litura pest control in chili leaf (Capsicum annum)Abstract. The armyworm pest (S. litura) is one of the pests that causes irregular perforated leaves, thus disrupting the photosynthesis process thereby reducing the production of chili plants so that pest management is necessary. The purpose of this study was to compare the effectiveness of B. thuringiensis with ozone technology generated through the Dielectric Barrier Discharge Plasma reactor in controlling S. litura on chili leaves in the laboratory. The research method consisted of several stages, namely (1) Maintenance of S. litura larvae (2) Ozone treatment and testing of S. litura (3) Toxicity testing of Bt isolates against S. litura.The results of this study will reveal about mortality (%),and change in population percentage (%). The treatment with Bacillus thuringiensis was very effective in controlling Spodoptera litura, it was seen 1 day after application (HSA) the caterpillar pests showed mortality (death), while the ozone treatment of mortality of S. litura only appeared 3 days after application (HSA). The results of the decrease in the number of S. litura pests on the application of B. thuringiensis bacteria were faster on the 4th day after application (HSA), namely 0 percentage of live caterpillars, while the ozone treatment until the 10th day of DSA still remained 20% of S. litura pests.