Judul: Application of essential oils in  insect repellent air freshner gel
Abstrak: Citronella and lavender oils are known as insect repellent. Composition of insect repellent, combined with aromatic fragrance, such as lemon, kaffir lime, and ylang-ylang oils were packed in an air freshner gel with the addition of patchouli oil as fixative agent. The purposes of this study are (1) to get the best concentration of patchouli oil as fixative agent; (2) to get the best composition of insect repellent active ingredients and fragrance materials, and (3) to know the resistance and the loss on fragrance odor in air freshner gel during use (fourteen days). The methods used are sensory test with skoring test, effectiveness test of the air freshner gel for repelling mosquito, and hedonic test. Then, the last methods used are sensory test and weighing. The research result show that the best concentration of patchouli oil as fixative agent is 1% patchouli oil. The next results, there are three best compositions of essential oils in air freshner gel formula that effectively repell insects. The first formula composition consist fragrance ingredient (lemon oil 2%) and the active ingredient of insect repellent (citronella oil 2% and lavender oil 2%). The second formula composition comprises fragrance material (kaffir lime oil 2%) and the active ingredient of insect repellent (citronella oil 3%). The third formula composition consisting of fragrance material (ylang-ylang oil 2%) and the active ingredient of insect repellent (citronella oil 2% and lavender oil 2%). Based on the result of hedonic test, the most preffered fragrance from the three formulas is formula with lemon fragrance. The last results, the resistance on fragrance odor can be estimated that is still acceptable until eight days of use and the loss on fragrance odor during use (fourteen days) can be estimated 54.89% (0.988 gram).
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Judul: Stick Preparation of Essential Oils Blend as Repellent Against Aedes aegepty
Abstrak: Minyak Atsiri merupakan minyak yang memiliki banyak kegunaan, diantaranya bermanfaat sebagai penolak nyamuk. Penelitian ini bertujuan mengetahui efektivitas daya tolak nyamuk dari campuran minyak atsiri terbaik dalam sediaan stick. Minyak atsiri yang digunakan yaitu minyak sereh wangi, lavender, geranium dan nilam. Minyak atsiri terlebih dahulu dilakukan karakterisasi warna, bobot jenis, indeks bias dan kelarutan dalam alkohol. Warna yang dihasilkan sesuai dengan SNI dan ISO yaitu kuning pucat sampai cokelat kemerahan, bobot jenis yang dihasilkan 0,880-0,970, indeks bias yang dihasilkan 1,462-1,509 dan larut dalam alkohol. Minyak atsiri yang digunakan tersebut menghasilkan 6 sampel, yaitu sampel J-O. Uji organoleptik pada sampel tersebut menunjukkan hasil bahwa sampel yang banyak disukai adalah sampel J dan M. Sampel terpilih dilanjutkan untuk dibuat menjadi repelan nyamuk dalam bentuk stick. Produk repelan selanjutnya dianalisis sifat fisiko-kimia dan diuji efektivitasnya. Produk repelan memiliki tampilan berwarna putih susu, mempunyai bau segar, tidak panas dikulit, pH normal sekitar 6-6,2, kestabilan baik, homogen dan tidak mengiritasi. Hasil dari uji efektivitas repelan produk J dan M sama-sama efektif dibandingkan dengan kontrol. Nilai daya proteksi yang dihasilkan dari kedua produk mencapai diatas 90% sampai jam ke-1., Essential oils has many uses, including being as a repellent for mosquitoes. This study aims to determine the effectiveness of the best essential oil mixture in stick form. Essential oils that used in this research are citronella, lavender, geranium, and patchouli oil. First, the essential oil is characterized by color, specific gravity, refractive index, and solubility in alcohol. The essential oil colors produced according to SNI and ISO are pale yellow to reddish-brown, the density is 0.880-0.970, the refractive index is 1.462-1.509 and dissolved in alcohol. The essential oil used produced 6 samples, namely the J-O sample. Organoleptic tests on these samples showed that the most preferred samples were sampled J and M. The selected samples were continued to be made into form of sticks. Repellant products have a milky white appearance, have a fresh odor, are not hot on the skin, normal pH is around 6-6.2, is good stable, homogeneous, and non-irritating. The results from the tests of products J and M were equally effective compared to controls. The value of the protective power generated from the two products reaches above 90% until the first-hour.
Keyword: Aedes aegypti, combination, essential oil, repellent stick

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. ,,,
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular.