Judul: Aplikasi Sitronelal Minyak Sereh Wangi pada Produk Eau de Toilette dengan Bahan Pewangi Alami
Abstrak: The increasing awareness for customer’s health, lifestyle, and environmental issues leads them to purchase products that have natural advantages, and one of those is natural fragrance. The purpose of this study is to formulate eau de toilette with natural fragrance using citronellal from citronella oil and other essential oils. Preliminary research was done by survey method to identify trends in perfume using and essential oil types preferred by customers. Primary research was done by formulating eau de toilette at 7.4% fragrance concentration. In this research, the hedonic test utilizes preference for clarity, natural fragrance, and overall fragrance product parameters. The formulation is a mixture of fragrances to 10 ml ethanol as a solvent. Based on hedonic test and selection of the best formulas using Bayes method, three formulas were selected with the highest score. The best formula is mixed between 0.3 ml patchouli oil, 0.2 ml jasmine oil, and 0.3 ml lemon oil. The second formula is mixed between 0.3 ml patchouli oil, 0.2 ml jasmine oil, 0.1 ml citronellal, and 0.2 ml lemon oil. The third formula is mixed between 0.3 ml patchouli oil, 0.2 ml jasmine oil, 0.1 ml citronellal, and 0.2 ml peppermint oil. The best three formulas have flower and fresh aroma.
Keyword: natural fragrance, essential oils, eau de toilette, citronellal

Judul: Pemisahan Fraksi Kaya Sitronelal, Sitronelol, dan Geraniol Minyak Sereh Wangi Menggunakan Distilasi Fraksinasi Vakum
Abstrak: The main compounds of citronella oil are citronellal, citronellol, and geraniol, all of which determine the fragrance intensity and price of the citronella oil it self. Separation of those compounds increased the value of citronella oil. The aim of this research is to obtain the optimum amounts of citronellal, citronellol, and geraniol fractions by vacuum of fractional distillation technology. Conditioning process using 30:1 reflux ratio obtioned purer citronellal, citronellol, and geraniol than conditioning process with 10:1 reflux ratio. The separation process was held in 5 - 4 mBar vacuum pressure and the variation of reflux ratio 10:10, 20:10, 30:10. The optimum amounts of citronellal, citronellol, and geraniol was obtioned in the variation of reflux ratio 10:10, they are 90.670 % of 620 ml, 41.101 % of 160 ml, and 53.581 % of 500 ml respectively
Keyword: vacuum fractional distillation, geraniol, citronellol, citronellal, citronella oil

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular