Judul: Pengaruh penambahan fungisida pada bahan pencuci serta suhu penyimpanan terhadap peningkatan kualitas Mangga (Mangifera indica L.) cv. Gedong
Abstrak: Mango sap is acidic and contain oil and sugar that attracts fungi infection that induce damage to the fruit, such as fruit rot and anthracnose infection. Previous research demonstrated that mango washer able to clean the sap but did not able to delay the occurrence of fruit rot. Therefore, fungicides were added in the washing material in the present study in order to delay the occurrence of fruit rot and anthracnose infection. Objective of present study was to obtain the best washing material composition, fungicide, and storage temperature in order to delay the occurrence of fruit rot and anthracnose infection in mango cv. Gedong. Research was conducted in Girinata Village, Cirebon and Postharvest Laboratory of Bogor Agricultural University from December 2014 to January 2015. The experiment was designed in a randomized complete design with two factors, named the combination of washing material and storage temperature. The first factor consists of 5 treatment, i.e., control (not washed), detergent 1% + Ca(OH)2 0.5%, detergent 1% + Ca(OH)2 0.5% + benomyl fungicide 0.025%, detergent 1% + Ca(OH)2 0.5% + azoxystrobin fungicide 0.025%, and detergent 1% + Ca(OH)2 0.5% + fludioxonil fungicide 0.025%. The second factor was 4 levels of temperature, i.e., room temperature, 18°C, 15°C and 12°C. All of factors has 3 replicaton and each replication contained 3 sample of fruits. All combinations of washing materials markedly better in cleaning sap and dirt on the mango, compare to control. Application detergent 1% + Ca(OH)2 0.5% + fludioxonil fungicide or azoxystrobin fungicide 0.025% and 12°C temperature is the best combination in delaying the occurrence of fruit diseases up to 30 days after harvest.
Keyword: Bogor Agricultural University, anthracnose, azoxystrobin, body rot, fludioxonil

Judul: Pengaruh Penambahan Fungisida pada Bahan Pencuci dan Waktu Pencucian terhadap Kualitas Buah Mangga (Mangifera indica) Varietas Arumanis.
Abstrak: Getah yang terdapat pada kulit mangga merupakan masalah bagi petani, karena dapat menurunkan kualitas. Salah satu usaha yang dapat dilakukan untuk mengurangi penurunan kualitas tersebut yaitu dengan melakukan pencucian menggunakan bahan pencuci yang bersifat basa. Percobaan ini bertujuan untuk membersihkan buah dari getah dan kotoran serta menghambat terjadinya busuk pada buah mangga. Percobaan ini dilaksanakan di Kecamatan Haurgeulis, Indramayu dan Laboratorium Pasca Panen, Departemen Agronomi dan Hortikultura, Fakultas Pertanian, Institut Pertanian Bogor pada Desember 2011 hingga Januari 2012. Rancangan percobaan yang digunakan adalah Rancangan Kelompok Lengkap Teracak (RKLT) dengan dua faktor. Faktor pertama terdiri dari lima macam perlakuan bahan pencuci, yaitu : P0 = tanpa perlakuan (kontrol), P1 = air, P2 = larutan Ca(OH)2 0.5 % dan deterjen, P3 = larutan Ca(OH)2 0.5%, deterjen 1%, dan fungisida, dan P4 = fungisida. Faktor kedua yaitu waktu pencucian yang terdiri dari dua macam yaitu : T1 = 0 jam setelah panen, dan T2 = 6 jam setelah panen. Pengamatan dilakukan kebersihan dari getah dan kotoran, luka bakar, dendritik, busuk pangkal buah, busuk buah, antraknosa, kekerasan, dan perubahan warna kulit buah. Hasil percobaan ini menunjukan bahwa larutan Ca(OH)2 0.5% + deterjen 1% + fungisida merupakan larutan paling baik untuk menghilangkan getah dan kotoran, mengurangi luka bakar sampai 6 HSP, mengurangi dendritik sampai 4 HSP, menunda busuk pangkal buah sampai 6 HSP, menunda busuk buah sampai 4 HSP dan menunda antraknosa sampai 8 HSP dibandingkan dengan buah mangga yang tidak dicuci dengan waktu pencucian 0 jam setelah panen dan 6 jam setelah panen. Bahan pencuci larutan Ca(OH)2 0.5% + deterjen 1% merupakan larutan yang dapat iii mempertahankan kualitas buah mangga, akan tetapi harus dilakukan pencucian 0 jam setelah panen untuk mendapatkan hasil yang baik.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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