Judul: Change of hydrocarbon Compounds During Bioremediation Processes of Soils Polluted by Crude Oil Using Gas Chromatography Mass Spectrophotometry.
Abstrak: Pollution handling that caused by crude oil contamination can use crude oil degrading microorganism. In this reseach change of hydrocarbon compounds degraded by bacteria were investigated with gas chromatography mass spectrophotometry (GCMS). The soils mixed with 5 % (b/b) crude oil was added with T2M bacteria isolated. The change of hydrocarbon compounds and total petroleum hydrocarbon (TPH) were measured every two weeks. TPH mesurement worked by gravimetry method with n-hexane solvent. Preparation for GCMS worked by soxhlet extraction. Extraction finished for 4 hours with 300 ml aseton:n-hexane (1:1) solvent. The extract dried by rotaryevaporator and measured with GCMS. The result of this reseach show that the biggest TPH decrease happened in nonsterilized soils and added bacteria with finally TPH 0.28 % and 93.3 % degradation. Soils were not added by bacteria had finally TPH 0.37 % and 90.17 % degradation. The soils were sterilized and added by bacteria had finally TPH 0.37 % and 90.17 % degradation, even the soils were sterilized and were not added by bacteria had finally TPH 1.37 % and 74.54 % degradation. The change hydrocarbon compounds during degradation process happened to long chain hydrocarbon became shorter hydrocarbon chain. This is showed by the decrease of percent area on chromathograme. The soils were not sterilized and added by bacteria showed the biggest changing because long chain hydrocarbon at the finally measurement were not detected.
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Judul: Perombakan Hidrokarbon Dalam Tanah Terkontaminasi Minyak Berat, Minyak Ringan dan Oli Bekas oleh Bacillus sp.
Abstrak: Oil is the main source of energy for humans activities such as industries and transportations. The oil exploration activities have potential to pollute the environment (i.e.soil, water, and air). The sludge released bysuch activities can be degraded by bacteria into non-harmful compounds. Biodegradation process is done to achieve the concentration of Total Petroleum Hydrocarbon (TPH) in the contaminated soil less than 1%. The result showed that the bacteria of Bacillus sp. ICBB 7859, ICBB 9461, ICBB 5071 were able to degrade the concentration of TPH of heavy oil from 9.5082% to 0.4673%, 10.7747% to 0.3607% and 9.2442% to 0.6713%, respectively. The three isolates of bacteria needed nine weeks to complete the process. For light oil, Bacillus sp. ICBB 7859 was able to decrease the TPH from 2.9407% to 0.4378%, ICBB 9461 from 3.1433% to 0.4702%, and ICBB 5071 from 3.0742% to 0.5991% respectively, within four weeks. For iv lubricant wastes, Bacillus sp. ICBB 7859 was able to decrease the TPH of lubricant wastes from 7.6949% to 0.9067, ICBB 9461 from 7.4556% to 0.9222%, and ICBB 5071 from 7.3459% to 0.6796% respectively. The three isolates of bacteria completed the degradation process in different time. Bacillus sp. ICBB 7859 and ICBB 9461 degraded lubricant wastes within six weeks, and Bacillus sp. ICBB 5071 degraded the lubricant wastes within five weeks to reach the TPH concentration of less than 1%.
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Judul: Rancangan kuda-kuda papan tipe mansard untuk kandang sapi perah
Abstrak: Tujuan penelitian ini adalah untuk mempelajari kekuatan rancangan kuda-kuda papan tipe mansard dan kekuatan sambungan yang menggunakan alat sambung paku, perekat dan gabungan dari paku dan perekat. Pemilihan tipe ini ditujukan untuk memperoleh ruangan yang cukup luas di bawah atap, dan digunakan sebagai tempat menyimpan persediaan pakan. Pengujian rancangan dilakukan terhadap model dengan pemberian beban vertikal. Model bersifat sama secara geometri (geomtrically similar). Sedang kekuatan sambungan diuji dengan pemberian beban tarik sejajar serat. Berdasarkan perhitungan, beban rencana rancangan kuda- kuda sebesar 1650 kg, dengan faktor keamanan 2,5 sehingga besar beban rencana model adalah 45,83 kg. Skala linier model N = 6. Dari pengujian, beban ijin model dengan alat sambung paku adalah 81,574 kg, sehingga beban ijin untuk rancangan kuda-kuda adalah 3000 kg. Oleh karena itu beban rencana (Pd) rancangan kuda-kuda papan diambil dari rata- ratanya, yaitu 2325 kg. Sambungan pada kuda-kuda papan cukup kuat menyalurkan tegangan yang ada. Hal ini terlihat dari jenis kerusakan yang terjadi pada saat pengujian yaitu patah pada batang kritis, sedangkan sambungan tetap dalam kondisi baik. Pada tingkat kepercayaan 95 persen, ketiga ukuran pelat sambung memberikan pengaruh yang nyata terhadap keku- atan sambungan paku. Sedang pada sambungan perekat dan gabungan dari paku dan perekat tidak memberikan perbedaan yang nyata. Sambungan paku mempunyai kekuatan terkecil, dibanding dengan sambungan perekat dan gabungan keduanya. Penggunaan ketiga macam alat sambung pada tiap-tiap ukuran pelat sambung, masing-masing menunjukkan adanya perbedaan pengaruh yang nyata terhadap kekuatan sambungan…dst
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