Judul: Studi Kelayakan Pendirian Pabrik Minyak Daun Cengkeh (Eugenia aromatica) di Kabupaten Halmahera Barat.
Abstrak: Clove leaf oil is an essential oil which derived from clove leaf. Clove leaf oil is used as a raw material by the industry because of the high content of eugenol. This research aims to provide an overview of information and feasibility of establishment clove leaf oil factory. The method used is the method of investment feasibility analysis. Market demand of clove oil higher than its supply. The capacity of clove leaf oil factory planned 2 tons of dried clove leaf/day, location in District Jailolo, West Halmahera. Investment required is about 722 million rupiah and working capital is about 165 million rupiah. Investment criteria indicates the value of Net Present Value is Rp 586 milion, IRR 20%, B/C Ratio 1.71, and Pay Back Period is 4 years and 3 months. Break-even point is reached when the sale of clove oil as much as 13 tons. The sensitivity analysis shows that the industry is feasible when the maximum decrease in production capacity is 6,85%, the maximum decrease of selling price is 4,1%, and the maximum increase purchase price of leaf clovers is 16,3%. Based on the results of research, the clove leaf oil factory is feasible for built in West Halmahera.
Keyword: Clove leaf oil, essential oil, feasibility studies, west halmahera

Judul: Kajian Pengaruh Bahan Baku Dan Nisbah Minyak Daun Cengkeh Dengan Larutan NaOH 10% Terhadap Rendemen Dan Karakteristik Isolat Eugenol
Abstrak: Indonesia has high potential clove leaves oil business opportunity especially in the areas that have high production of cloves, example Java island with cloves cultivation area are about ± 50,000 ha (Balitro 2005) .. It's predicted have falls clove leaves about ± 305 tones/day or equivalent with 4.4 ton clove leaves oil/day. According to Uhe (2005), International market prices for clove leaves oil on February 2005 are 4.25 US Dollar per kg. One way to increase clove leaves oil value is producing isolate compound of clove leaves oil, called eugenol. Eugenol prices is more expensive than clove leaves oil. For illustration, while clove leaves oil prices is Rp. 25,000lkg, eugenol prices is Rp. 75,000/kg (lndesso, 2006). In international market, eugenol from Indonesia has lower raw price because of its lower quality. The price is about 5.15 US Dollar per kg CUhe 2(05). Eugenol can be used as raws material in pharmaceutical, cosmetic, food industries, and also as mixture in ingredient for cigarette industries. Eugenol was produce by isolating eugenol from clove leave oil. The chemical process of eugenol isolating is conducted by reaction of clove ' leave oil and strong base by using (Natrium Hidroxyde) to form Na-eugenolat. Eugenol can be regmerated from Na-eugenolat by using the HCI solution. Based on Sumangat et. al research (2003), eugenol isolation with NaOH 6% and ratio of clove leaves and NaOH is 1:7 producing eugenol with yield 67.8- 68.3, purity 99.3% - 99.5% and effectively about 89.5%. The aim of this research is to get the best combination treatment between raws material and ratio between clove leaves oil and NaOH 10%. Distillation method will be doing in 2 ways, treatment will be conducted for distilled clove leaves oil with steam method and condensation method. Ratio between Clove leaves oil and NaOH 10% are 1: 2; 1 : 2.5; and 1 : 3. Treatment design will be using Complete Factorial Random Design Clove leaves oil reacting with NaOH 10%, squealer for 30 minutes with 590 rpm, left for 24 hours, then the substratum which is eugenol compound reacting with HCl 6%, then it washes using hexane. The yield, purity, effectively, and also the physical chemical of eugenol (i.e. refraction index, density, purity, solubility in ethanol 70% and colour) were analysed. The analysis shows that distilled clove leaves oil method affecting the yield, degree of purity, isolation process effectively, and isolat eugenol yield aspect, but the ratio clove leaves oil with NaOH 10% affecting isolation process effectively, and isolate eugenol yield. The Yield by distillation method of clove leaves oil are 63.71 % while steam method are 63.24%. Yield by ratio treatment of clove leaves oil and NaOH 10% (1: 2~ 1 : 2.5; 1 : 3) in sequence arc 63.37 %, 63.62 (%, ancl 63.44%. Eugenol purity by distillation method of clove leaves oil are 97.24 % while by steam method are 98.36 %. Eugenol purity by ratio treatment of clove leaves oil and NaOH 10% (1: 2; 1 : 2.5; 1 : 3) in sequence are 97.44 %,97.57 (Xl, and 98.39 %, and the isolation
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Judul: Solusi Geometri Schwarzschild untuk Dimensi 4+1 dengan Invarian Rotasi Isotropik.
Abstrak: Metrik Schwarzschild merupakan solusi eksak pertama dari persamaan medan Einstein dengan mangasumsikan metrik statik dan simetris. Metrik Schwarzschild yang ditemukan oleh Karl Schwarzschild masih dalam dimensi 3+1, namun seiring dengan teori-teori terbaru yang menunjukkan bahwa alam semesta tidak hanya di dimensi 3+1. Maka melalui penambahan dimensi, tujuan penelitian ini memperoleh solusi pada geometri Schwarzschild untuk dimensi 4+1 dengan memodifikasi koordinat bola yang invarian rotasi isotropik dan melalui penurunan rumus seperti koordinat bola, simbol Christoffel, dan tensor Ricci. Selain mendapatkan solusi ini, metrik Schwarzschild dimensi 4+1 dapat digunakan sebagai metrik dasar untuk memperoleh solusi blackhole dan wormhole pada dimensi 4+1. Hasil akhirnya, dengan memanfaatkan modifikasi koordinat bola, metrik Schwarzschild dapat dibentuk sehingga diperoleh solusi geometri Schwarzschild untuk dimensi 4+1.
Keyword: metrik Schwarzschild, persamaan medan Einstein, modifikasi koordinat bola, penambahan dimensi, invarian rotasi isotropik