Judul: Heavy Metal Pollution in Gunung Putri Swamp Waters, Bogor
Abstrak: Rawa Gunung Putri merupakan ekosistem perairan tawar yang sumber airnya berasal dari air hujan dan mata air. Keberadaannya di kawasan industri Gunung Putri menyebabkan rawa ini rentan terhadap pencemaran aliran limbah industri maupun penduduk. Penelitian ini bertujuan menganalisis kandungan logam berat Pb dan Cd baik di air, sedimen dan biota ikan dan katak, dilakukan pada 3 plot contoh hulu-tengah-hilir rawa. Analisis logam berat di Laboratorium Terpadu IPB menggunakan metode AAS. Hasil penelitian menunjukkan logam Pb dan Cd tidak terdeteksi di air rawa, tetapi terdeteksi Pb pada sedimen di ketiga plot contoh. Pb pada ikan terdeteksi antara <0,2-0,27 mg/kg, serta Pb pada katak <0,2-0,27 mg/kg. Tidak terdeteksinya Pd dan Cd di air rawa diduga karena tidak adanya sumber limbah cair industri sekitar rawa yang menghasilkan limbah logam berat, serta penyerapan logam berat oleh tumbuhan air rawa dan mengendapnya logam bersama partikel tersuspensi ke dasar rawa. Adapun Pb pada daging ikan dan katak melebihi bakumutu daging konsumsi yang telah ditetapkan.
Keyword: logam berat, pencemaran, rawa gunung putri

Judul: Kandungan Logam Berat Pb dan Cd pada Sedimen di Waduk Saguling, Bandung, Jawa Barat
Abstrak: Saguling Reservoir is a reservoir that received water flow from the Citarum River, which was pouled by many industrial wastes. These wastes contain heavy metals such as Pb and Cd that contaminated water, sediment and biota in the reservoir. The observation on the sediment, is expected to give a results about nominal level of the heavy metal pollution in that reservoir. The result showed that the content of heavy metal Pb and Cd was 8.623 ppm and 0.721 ppm. The value of both heavy metals at each station states that the levels of heavy metal pollution in sediments has exceeded the standard quality by EPA (1987) in the Laws (1993). In comparison with the content of heavy metals in water, sediment has a greater concentration with an average ratio of 11:1. Whereas v sediment in comparison with the content of heavy metals in Tutut, they have a smaller concentration values with an average ratio of 0.4:1. Distribution value of the heavy metal Pb and Cd in Saguling Reservoir have the same pattern, is high in inlet, and then decrease in the middle and increase surpass the inlet. The recommended supervision to reduce waste pollution in Saguling, is the implementation of the waste water treatment (IPAL) to industries that dispose their wastes to the water.
Keyword: Saguling Reservoir, Heavy metals, Pollution

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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