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: Process design in the production of isoeugenol and vanillin from eugenol of clove leaf oil
Abstrak: Clove leaf oil contains a high amount of eugenol (70-95%) and hence it has been considered as a potential raw material for production of isoeugenol and vanillin, which have high economic value. This study was aimed at designing production of isoeugenol and vanillin from eugenol of clove leaf oil and analyzing the potential product development financially.The specific objectives of this research work are 1) Identify the isoeugenol and vanillin, 2) Model simulation of process design of isoeugenol and vanillin, 3) Study on financial feasibility and added value. This research is expected to provide maximum economic potential of eugenol to enhance the added value of clove leaf oil. The results showed that the FTIR and NMR products confirmed that isoeugenol and vanillin present in the synthesized product were identical to the reference standards. Model simulation of process design suggested that isomerization reaction of eugenol to produce isoeugenol occurred at temperatures of 25-200oC and 1 atm pressure, with the average conversion and isoeugenol of 90% and product purity of 89,6%. Meanwhile, oxydation of isoeugenol which then produced vanillin took place at temperatures of 19.22-150oC and 1 atm pressure resulting in the average conversion of 90% and product purity of 98%. Financial analysis on isoeugenol and vanillin industries showed feasible at production capacities of 1,157,280 kg/year and 853,929 kg/year respectively, with total investment of Rp. 3,795,050,000 and 3,795,050,000 as well as working capital of Rp. 127,487,726,119 and Rp. 154,794,595,559 respectively. At an interest rate of 12% and 10 years project lifetime showed the NPV of Rp. 645,341,441,970 and Rp. 779,561,530,094 respectively. Furthermore, the IRR were 47,40% and 47,43%; net B/C ratio 3.90 and 3.91; BEP 8,178 and 5,063 products unit; PBP 1.27 and 1.25 years. Value added of eugenol to isoeugenol and vanillin industry were Rp. 145,193 and Rp 175,651/kg respectively, while labor incomes were Rp. 447.0 and Rp. 2.190/kg, processor profits Rp. 144.476 and Rp. 173.461/kg. It is concluded that designing industrial production of isoeugenol and vanillin from eugenol of clove leaf oil is financially feasible.
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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