Judul: Social Behavior of Tricolour langur (Presbytis chrysomelas ssp. cruciger) at Majang Island Resort, Danau Sentarum National Park, Social Behavior of Langur Borneo (Presbytis chrysomelas ssp. cruciger) at Majang Island Resort, Danau Sentarum National Park
Abstrak: Langur borneo (Presbytis chrysomelas cruciger) merupakan jenis langur endemik kalimantan yang kini memiliki status keterancaman kritis, namun belum masuk ke dalam satwa dilindungi secara hukum di Indonesia. Hal ini disebabkan oleh minimnya acuan data mengenai bio-ekologi langur borneo, salah satunya perilaku sosial. Tujuan penelitian ini adalah mengidentifikasi perilaku sosial, menganalisis organisasi, dan interaksi langur borneo dengan jenis primata lain. Penelitian dilaksanakan pada Juli-Agustus 2021 di Resort Pulau Majang, Taman Nasional Danau Sentarum. Metode pengambilan data perilaku sosial dengan scan sampling dan pencatatan continuous recording. Hasil perilaku sosial yang didapatkan ialah vokalisasi (34,48%), menelisik (20,69%), agonistik (13,79&), seksual (3,45%), dan bermain (27,59%). Langur borneo hidup secara berkelompok dengan hirarki sosial yang dipimpin jantan dewasa. Tidak terlihat adanya interaksi langsung dengan jenis primata lain di Pulau Majang, selain tumpang tindih habitat akan ketersediaaan pakan.
Keyword: Danau Sentarum National Park, Langur Borneo, social behaviors, social organization.

Judul: Habitat Characteristics and Diet of Langur Borneo at Pulau Majang Resort, Danau Sentarum National Park
Abstrak: Langur Borneo (Presbytis chrysomelas ssp. cruciger Thomas 1892) merupakan primata endemik Borneo yang memiliki wilayah persebaran sempit dengan status perlindungan kritis menurut daftar merah IUCN. Penelitian ini bertujuan mengidentifikasi karakteristik habitat langur Borneo; mengidentifikasi jenis tumbuhan pakan, bagian yang dimakan, dan jenis pakan lain; serta menganalisis ketersediaan jenis tumbuhan pakan langur Borneo. Penelitian dilaksanakan di Resort Pulau Majang, Taman Nasional Danau Sentarum dengan pengambilan data lapangan dilaksanakan pada Juli-Agustus 2021. Pengumpulan data dilakukan dengan pengukuran langsung, observasi lapangan, dan studi literatur. Di Resort Pulau Majang hanya dijumpai pada hutan sekunder dengan suhu harian berkisar antara 24,70oC-29,15oC dengan kelembapan harian antara 81,50%-99%. Teridentifikasi 8 jenis tumbuhan pakan langur dengan persentase tertinggi bagian yang dimakan adalah buah (63,64%). Hal tersebut disebabkan oleh waktu penelitian bersamaan dengan musim buah bukit. Nilai kerapatan dan kerapatan relatif pada semai dan pancang lebih tinggi dibandingkan pada tiang dan pohon. Hal tersebut menunjukkan bahwa ketersediaan pakan di lokasi penelitian terbilang cukup baik., Langur Borneo (Presbytis chrysomelas ssp. cruciger Thomas 1892) is an endemic primate of Borneo that has a critically endangered status according to the IUCN Red List. This study aims to identify habitat characteristics of the langur Borneo; identify the types of their feed plants, the parts that were eaten, and other types of feed; and analyze the availability of the langur Borneo’s feed. This research was carried out at Pulau Majang Resort, Danau Sentarum National Park in July- August 2021. Data were collected by direct measurements, field observations, and literature studies. Langur Borneo at Pulau Majang Resort was only found in secondary forests with daily temperatures ranging from 24,70 ̊C–29,15 ̊C and daily humidity between 81,50%-99%. Eight types of food plants of langur were identified with the highest percentage of the part eaten as fruit (63,64%). The hill fruit season made it the common finding of langur’s feed. Density and relative density values at each growth rate of seedlings and saplings are higher than poles and trees. This shows that the availability of langur Borneo’s feed at Pulau Majang Resort is quite good.
Keyword: Diet, habitat characteristics, Langur Borneo

Judul: Pembuatan Film Tipis Cu2ZnSnS4 sebagai Lapisan Penyerap Cahaya pada Sel Surya Menggunakan Metode Elektrodeposisi
Abstrak: Thin film of Cu2ZnSnS4 (CZTS) is an alternative semiconductor used as light absorber layer on solar cell. CZTS can replace silicon that commonly used as commercial semiconductor. The advantage of using CZTS as absorber layer is due to the abundance of its chemical composer on earth, and its high value of absorption coefficient. The absorber layer was made by using electrodeposition method on ITO glass substrates. The films were deposited at room temperature using potentiostatic mode with a potential of –1.05 V for 30, 45, and 60 minutes. After that, the films were annealed at two different temperatures, 180 ºC and 500 °C, for 45 minutes in N2/H2S atmosphere. Based on X-ray diffraction analysis, the polycrystalline thin film obtained fall into kesterite crystal phase. This type of crystal was obtained when the CZTS was annealed at 500 °C in H2S/N2 atmosphere. The value of optical band gap energy for the CZTS thin film was 2.2 eV with the film thickness about 1.228–6.366 μm. The sample of CZTS with electrodeposition time of 45 minutes and annealing temperature of 500 °C showed the best result and in conformity with absorber layers criteria for solar cells.
Keyword: semiconductor, ITO glass, CZTS thin film, electrodeposition