Judul: Heavy Metals Content (Pb, Hg, Cd) in Crescent Grunter (Terapon jarbua, Forsskål 1775) in Bacan Island Waters
Abstrak: Pulau Bacan memiliki potensi perikanan dan pariwisata yang tinggi. Kegiatan pariwisata dan kehidupan masyarakat sekitar berpotensi menjadi penyumbang cemaran logam berat ke lingkungan perairan tersebut. Salah satu potensi perikanan dengan nilai ekonomis penting yang terdapat di pulau ini adalah ikan kerong-kerong yang banyak dimanfaatkan sebagai bahan pangan baik dalam kondisi segar maupun olahan ikan asin-kering. Penelitian ini bertujuan menganalisis tingkat bioakumulasi logam berat Pb, Hg, dan Cd pada organ hati, insang, dan daging ikan kerong-kerong (Terapon jarbua, Forsskål 1775) di Perairan Pulau Bacan, Maluku Utara. Pengambilan sampel air, pengukuran kualitas air, serta pengambilan organ hati, insang, dan daging pada ikan kerong-kerong dilakukan pada bulan Februari 2022. Berdasarkan hasil anlisis, nilai kandungan logam berat Pb, Hg, dan Cd pada air telah melampaui baku mutu PP RI No. 22 tahun 2021 dan kandungan logam berat Pb pada hati ikan kerong-kerong ditemukan dalam konsentrasi tertinggi. Biokonsentrasi logam berat tergolong akumulasi rendah, kecuali Pb pada organ hati termasuk akumulasi sedang., Bacan Island has high fishery and tourism potential. Tourism activities and the life of the surrounding community have the potential to contribute to heavy metal contamination in the aquatic environment. One of the fishery potentials with important economic value found on this island is kerong-kerong fish which is widely used as a food ingredient both in fresh condition and processed salt-dried fish. This study aims to analyze the level of bioaccumulation of heavy metals Pb, Hg, and Cd in the liver, gills, and meat of crescent grunter (Terapon jarbua, Forsskål 1775) in Bacan Island waters, North Maluku. Sampling of water, measurement of water quality, as well as harvesting of liver, gills, and meat from crescent grunter was carried out in February 2022. Based on the results of the analysis, the values for the heavy metal content of Pb, Hg and Cd in water exceeded PP RI quality standards No. 22 of 2021 and the content of the heavy metal Pb in the liver of clam fish was found to be in the highest concentration. Bioconcentration of heavy metals is classified as low accumulation, except for Pb in the liver which is classified as moderate accumulation.
Keyword: Bacan Island, crescent grunter, heavy metals

Judul: Heavy Metal Content of Hg, Pb, and Cd in Skipjack Tuna Katsuwonus pelamis (Linnaeus, 1758) in Waters of Bacan Island, North Maluku
Abstrak: Pulau Bacan memiliki sumberdaya perikanan yang sangat potensial. Namun, di Pulau Bacan berlangsung aktivitas antropogenik seperti pertambangan, pertanian, perkebunan, dan pelabuhan yang berpotensi menimbulkan pencemaran logam berat di perairan. Penelitian ini bertujuan menganalisis tingkat bioakumulasi logam berat Hg, Pb, dan Cd pada ikan cakalang (Katsuwonus pelamis Linnaeus, 1758) di perairan Pulau Bacan, Halmahera Selatan, Maluku Utara. Pengambilan sampel air dan pengukuran parameter kualitas air serta pengambilan bagian daging, insang, dan hati ikan cakalang berlangsung pada bulan Februari 2022. Pada air, kandungan logam berat Hg, Pb, dan Cd telah melampaui baku mutu. Kandungan logam berat Hg, Pb, dan Cd tertinggi pada ikan cakalang ditemukan pada hati, sedangkan terendah pada daging. Pada daging ikan cakalang, tingkat akumulasi Hg, Pb, dan Cd tergolong rendah., Bacan Island has a high potential of fishery resources. However, anthropogenic activities such as mining, agriculture, and ports taking place on Bacan Island cause heavy metal pollution in the waters. This study aimed to analyze the bioaccumulation level of heavy metals such as Hg, Pb, and Cd in skipjack tuna (Katsuwonus pelamis Linnaeus, 1758) in the waters of Bacan Island, South Halmahera, North Maluku. Water sampling, measurement of water quality parameters and fish sampling was conducted in February 2022. In the water, the heavy metals concentration of Hg, Pb, and Cd has exceeded the quality standard. The highest concentration of Hg, Pb, and Cd was found in the liver, while the lowest was in the muscle. In skipjack tuna muscle, the accumulation level of Hg, Pb, and Cd is low.
Keyword: Bacan Island, heavy metal, skipjack tuna

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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