Judul: Peningkatan Kualitas Kompos Tandan Kosong Kelapa Sawit Dengan Abu Boiler Dan Pengaruhnya Terhadap Sifat Kimia Ultisol Serta Tanaman Sawi (Brassisca Juncea L.).
Abstrak: Produksi minyak kelapa sawit menghasilkan limbah antara lain tandan kosong kelapa sawit dalam jumlah yang sangat banyak, limbah cair, cangkang, dan serat. Tandan kosong kelapa sawit memiliki unsur hara lengkap, tetapi kandungannya rendah, sehingga perlu penambahan bahan yang mengandung unsur hara tinggi seperti abu boiler. Abu boiler adalah limbah yang dihasilkan dari proses pembakaran cangkang dan serat pada suhu yang tinggi. Bahan ini berpotensi cukup tinggi sebagai bahan tambahan untuk meningkatkan kualitas kompos tandan kosong kelapa sawit. Oleh karena itu, perlu dilakukan pengomposan tandan kosong kelapa sawit yang ditambah abu boiler pada awal proses pengomposannya. Penelitian ini bertujuan untuk mempelajari: 1) pengaruh penambahan abu boiler terhadap kualitas kompos tandan kosong kelapa sawit, 2) pengaruh kompos tandan kosong kelapa sawit terhadap sifat kimia Ultisol, serta pertumbuhan, produksi dan kadar hara tanaman sawi. Penelitian ini terdiri dari dua percobaan, percobaan pertama adalah peningkatan kualiatas kompos tandan kosong kelapa sawit dengan penambahan abu boiler. Perlakuan pada percobaan pertama terdiri dari empat tingkatan dosis abu boiler yaitu K1 = 0%, K2 = 15%, K3 = 25%, dan K4 = 35%. Percobaan kedua adalah percobaan rumah kaca, terdiri dari tiga belas perlakuan dengan tiga ulangan yang ditempatkan dalam rancangan acak lengkap (RAL). Perlakuan yang diberikan terdiri dari empat jenis kompos (K0, K1, K2, K3) yang dikombinasikan dengan tiga taraf dosis kompos yaitu D1 = 10 t/ha, D2 = 20 t/ha, dan D3 = 30 t/ha. Data pengamatan dianalisis secara statistika menggunakan Analisys of Variance (ANOVA) dengan uji F pada taraf alfa 5%. Jika perlakuan berpengaruh nyata dilanjutkan dengan uji lanjutan Duncan Multiple Range Test (DMRT) pada taraf alfa 5%. Hasil penelitian menunjukkan bahwa pemberian abu boiler pada awal proses pengomposan dapat memperbaiki kualitas kompos tandan kosong kelapa sawit antara lain meningkatkan pH, kadar asam humat, unsur hara makro dan mikro serta menurukan nisbah C/N. Pemberian berbagai dosis kompos tandan kosong kelapa sawit yang di tambahkan abu boiler pada Ultisol berpengaruh nyata meningkatkan pH H2O, P2O5, C-organik, N-total, Ca-dd, K-dd tanah dan menurunkan Al-dd dan H-dd tanah. Perbaikan sifat kimia tanah nyata meningkatkan pertumbuhan, dan produksi sawi serta cenderung meningkatkan kadar hara tanaman sawi. Kata kunci: abu boiler, tandan kosong kelapa sawit, asam humat, Ultisol
Keyword: abu boiler, tandan kosong kelapa sawit, asam humat, Ultisol

Judul: Perbaikan kualitas kompos tandan kosong kelapa sawit dengan penambahan abu boiler serta pengaruhnya terhadap sifat kimia podsolik merah kuning dan tanaman caisim (Brassica juncea)
Abstrak: Processing of oil palm fresh fruit bunch (FFB) to get crude palm oil (CPO) will produce some waste, among others is the oil palm empty fruit bunch (EFB). The EFB is abundantly produced in any plantations that without carefull handling will induce a problem to the environment. Some plantations have been using the EFB to produce compost. However, the quality of their compost from EFB is highly varies due to the use of different composting method. On the other hand, boiler ash of oil palm processing unit contains various and significance chemical elements that can be used to chemically improve the quality of EFB compost. This research was aimed to study: 1) the difference in quality of EFB composts produced by different composting methods, before and after addition of boiler ash, and 2) the influence of boiler ash-enriched EFB compost to chemical properties of Red Yellow Podzolic and mustard productivity. Each of EFB compost produced by opened method (K1) and by closed method (K2) were treated with four levels of boiler ash doses (A0 = 0%, A1 = 5%, A2 = 10%, and A3 = 15%). Both of materials are mixed and incubated for 2 weeks. Then boiler ash-enriched EFB compost were mixed with soil (compost : 20% and soil : 80% by volume) and used as medium to grow mustard in green house experiment. The experiment was designed in completely randomized design with 9 treatments and 3 replications. The treatments were comprise of control, K1A0, K1A1, K1A2, K1A3, K2A0, K2A1, K2A2 and K2A3. The results showed that the addition of boiler ash into EFB compost increased pH from 7,0 to 7,4-7,8 for K1 and from 7,6 to 7,7-7,8 for K2. The increase of compost pH was in accordance with the increase of boiler ash dose. Whereas macro and micro nutrients content was not influenced by the addition of boiler ash. Boiler ash-enriched EFB compost increased pH of Red Yellow Podzolic. K1 did not influenced C-organic, P-available, K-exchangeable, Ca-exchangeable and Mg-exchangeable content of Red Yellow Podzolic. In contrast, K2 increased P-available, K-exchangeable and Ca-exchangeable of Red Yellow Podzolic. Beside that, boiler ash-enriched EFB compost increased growth, yield and N, P, K, Ca, Mg content of mustard. The yield of mustard increased about 173,5% – 226,5% for K1 and 279% – 290% for K2 compared to control (68 g/plot).
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Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
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