Judul: Exploration of Crab (Crustacea: Decapoda: Brachyura) from the East Coast, North Sumatera
Abstrak: Crustacea merupakan hewan invertebrata yang memiliki tingkat migrasi yang tinggi. Kemampuan migrasi ini terjadi pada fase larvanya yang mengikuti arus dan akan menetap pada habitat yang cocok. Pantai Timur Sumatera yang berada di antara Selat Malaka dan Sungai Deli diprediksi memiliki keanekaragaman kepiting yang tinggi. Penelitian ini bertujuan mengeksplorasi dan mendeskripsikan keanekaragaman kepiting di kawasan Pantai Timur, Sumatera Utara. Metode yang digunakan adalah convenience sampling yaitu teknik pengambilan sampel didasarkan pada ketersediaan dan kemudahan mendapatkan sumber data. Penelitian ini dilakukan pada 4 stasiun penelitian dan sampel difiksasi pada alkohol 70% selama satu 24 jam, selanjutnya disimpan menggunakan alkohol 96% dan satu bulan kemudian alkohol 96% diganti yang baru. Kepiting diidentifikasi menggunakan FAO Species Identification Guide for Fishery Purpose. Hasil sampling didapatkan sebanyak 192 individu, terbagi kedalam 6 famili dan 21 spesies. Famili tersebut terdiri dari Sesarmidae (7 spesies), Ocypodidae (7 spesies), Portunidae (4 spesies) , Macrophthalmidae (1 Spesies), Varunidae (1 spesies) , dan Camptandriidae (1 spesies). Kata kunci : belawan, convenience sampling, larva, selat malaka, Crustaceans are invertebrate animals that have a high migration rate. This migratory ability occurs in the larval phase, which follows the current and will settle in a suitable habitat. The East Coast of Sumatra, which lies between the Strait of Malacca and the Deli river, is predicted to have a high diversity of crabs. This study aims to explore and describe the diversity of crustaceans in the Belawan International Port area, North Sumatra. The method used is convenience sampling, the sampling technique is based on the availability and ease of obtaining data sources. This study was conducted at 4 research stations and samples were fixed in 70% alcohol for one 24 hours, then stored within 96% alcohol relaced with new one. Samples identified using the FAO Species Identification Guide for Fishery Purposes. Sampling results obtained as many as 192 individuals, divided into 6 families and 21 species. The family consists of Sesarmidae (7 species), Ocypodidae (7 species), Portunidae (4 species), Macrophthalmidae (1 species), Varunidae (1 species), and Camptandriidae (1 species). Keywords: belawan, convenience sampling, larva, strait of malacca
Keyword: belawan, convenience sampling, larva, strait of malacca

Judul: Diversity of Crab Species (Decapoda: Brachyura and Anomura) on the West Coast of North Sumatra, Central Tapanuli Regency and Sibolga City, North Sumatra Province
Abstrak: Zona intertidal adalah bagian dari ekosistem laut yang meliputi antara ekosistem perairan dan daratan. Kepiting (Decapoda: Crustacea) merupakan salah satu hewan yang dapat ditemukan di wilayah intertidal yang lingkungannya sangat ekstrim akibat pengaruh pasang surut. Keanekaragaman jenis kepiting dapat dijadikan sebagai informasi biodiversitas yang sangat penting dalam kajian ilmiah/penelitian, pendidikan, keberlangsungan pemanfaatan spesies, eksplorasi potensi hayati dan monitoring spesies, ekologi, membuat kebijakan dan untuk pengembangan inovasi bioteknologi. Penelitian ini bertujuan untuk mengetahui dan mendeskripsikan keanekaragaman jenis kepiting (Decapoda: Brachyura dan Anomura) di pesisir pantai barat Sumatera Utara, Kabupaten Tapanuli Tengah dan Kota Sibolga, Provinsi Sumatera Utara. Purposive sampling adalah metode yang digunakan dalam penelitian ini karena efisien dan mudah diterapkan, juga memberikan kebebasan yang bertanggung jawab kepada peneliti dengan keterbatasan yang ada. Ketujuh stasiun yang diamati merupakan zona intertidal dengan substrat yang berbeda-beda dan memperoleh 24 spesis kepiting dari 13 genus yang termasuk dalam tujuh famili, yaitu Portunidae, Xanthidae, Grapsidae, Sesarmidae, Plagusiidae, Menippidae dan Porcellanidae. Dari ketujuh famili tersebut yang didominasi dari infraordo Brachyura, terdapat satu spesies yang merupakan kelompok infraordo Anomura, yaitu Petrolisthes tuberculatus yang termasuk ke dalam famili Porcellanidae. Diantara 24 spesies, terdapat sebelas spesies yang merupakan laporan penyebaran pertama (new record) dari laut Indonesia.
Keyword: Biodiversity information, intertidal, new record, purposive sampling.

Judul: Hybrid solar cells of ZnO nanoparticles/chlorophyll was modified metal ions (Zn2+ and Cu2+ )
Abstrak: Zinc Oxide (ZnO) is a n-type semiconductor with a wide the energy band (Band Gap) is 3.37 eV at room temperature and 3.34 eV at low temperature with a large exiton binding energy is 60 meV. ZnO has been synthesized by hydrothermal method, resulting in a decrease in particle size over the duration of the hydrothermal changes. Crystallographic structure of ZnO were characterized using XRD, has shown the characteristic pattern of a hexagonal wurtzite structure, the crystallite size increases to changes in particle size. Changes in particle size has also led to a change in the absorption peak of ZnO as has been demonstrated posted under test using the optical properties of UV-Vis spectrophotometer. Changes of this uptake has also led to changes in the energy band gap, which increases its band gap energy of the particle size. In electronic applications, especially in solar cells. Chlorophyll is considered less effective, because of their very nature are easily degraded as a result of several reactions which are acid, lighting and temperature. The results of the stability test using a halogen lamp 34 W/m2 for 5 hours, that the substitution of chlorophyll with metal ions Zn2+ and Cu2+ has been shown to form more stable than natural chlorophyll. The characterization of the optical properties, the combination of ZnO / chlorophyll in the form of hybrid films has led to a shift in the absorption region of ZnO becomes more widely from the UV to Visible. ZnO/chlorophyll has absorption range of 350-515 nm, ZnO / Zn-feofitin 332-401 nm and 332-632 nm for Cu-feofitin. The combination of ZnO/chlorophyll and CuSCN as a solid electrolite in hybrid solar cell, a modified chlorophyll with metal ions Zn2+ and Cu2+ has been shown to form a more stable I-V curve. It is characterized by its fill factor value greater than natural chlorophyll. Nevertheless, solar cells with natural chlorophyll has been able to produce higher efficiency values of chlorophyll were substituted.
Keyword: Hydrothermal, ZnO/Chlorophyll modified, Hybrid Solar Cell