PUBLIKASI - LEMBAGA ILMU PENGETAHUAN INDONESIA

pengaruh Nutrisi dan Suhu Terhadap Selektivitas Potensi Antibakteri dari Bakteri yang berasosiasi dengan spons

Aktifitas farmakologi yang dihasilkan oleh mikroorganisme laut sangat dipengaruhi oleh nutrisi dan kondisi lingkungan. Hal tersebut mendorong untuk digali lebih dalam tentang aspek-aspek yang mempengaruhi seleksi mikroba potensial pada spons. Metode isolasi mikroba dari jaringan spons menjadi kunci dalam menguak potensi mikroba simbionnya. Dalam penelitian ini akan membahas pengaruh berbagai media isolasi bakteri yang berasosiasi dengan spons asal Kep. Seribu. Terhadap 3 specimen spons Sp1(Theonella Sp.) , Sp2 ( dan Sp3 dilakukan isolasi bakteri dengan metode direct sampling menggunakan media M1, M2 dan M3. Media M1 mengandung nutrisi antara lain amilum, ekstrak khamir dan pepton, sedangkan media M2 mengandung sumber… Selengkapnya

The influence of tempering process for DP lateritic steel in hardness and microstructure behavior

Abstract. In this study, the influence of tempering temperature on dual phase (DP) steel lateritic has been examined. Lateritic is chosen because of its excellence as austenite stabilizer in the formation of martensite and also increase the weldability due to nickel content. The hardness and microstructure behavior of steels were the main focus of this research. One of the goals was to obtain the combination of high strength and ductile materials for automotive application. The specimens used in this study were low carbon steel made by the hot-rolled process and followed by the initial heating process with various temperature (760°C,… Selengkapnya

Influence of Sintering Temperature on Mechanical and Physical properties of Mill Scale based Bipolar Plates for PEMFC

This work concerns the utilization of mill scale, a by-product of iron and steel formed during the hot rolling of steel, as a potential material for use as bipolar plates in proton exchange membrane fuel cells (PEMFCs). On the other hand, mill scale is considered a very rich in iron source having characteristic required such as for current collector in bipolar plate and would significantly contribute to lower the overall cost of PEMFC based fuel cell systems. In this study, the iron reach source of mill scale powder, after sieving of 150 mesh, was mechanically alloyed with the aluminium source… Selengkapnya

Plasma polymer facilitated magnetic technology for removal of oils from contaminated waters

Oil pollution of waters is one of the most serious environmental problems globally. The long half-life and persistence within the environment makes oil particularly toxic and difficult to remediate. There is a significant need for efficient and cost-effective oil recovery technologies to be brought in to practice. In this study, we developed a facile and efficient magnetic separation method. The surface of 316L stainless steel nanoparticles was modified by plasma deposition of 1,7-octadiene and perfluorooctane, producing relatively hydrophobic coatings having water contact angles of 86 and 100°, respectively. Both coatings had high oil removal efficiency (ORE) of >99%. The captured… Selengkapnya

Pelestarian dan Pemanfaatan Keanekaragaman hayati Indonesia: Peluang dan Tantangan

ABSTRAK Pelestarian dan Pemanfaatan Keanekaragaman Hayati Indonesia: Peluang dan Tantangan Siti Nuramaliati Prijono Lembaga Ilmu Pengetahuan Indonesia Indonesia yang terletak di kawasan tropis, memiliki keanekaragaman hayati yang tinggi yang meliputi keanekaragaman pada tingkat ekosistem, jenis dan gen. Meskipun demikian, ternyata Indonesiapun mempunyai jumlah yang cukup banyak jenis-jenis yang terancam punah di dunia. Faktor-faktor utama yang mengancam kepunahan adalah kerusakan habitat, perburuan, introduksi species dan adanya konversi habitat-habitat alam ke penggunaan lainnya. Sebagai usaha untuk menjaga kelestarian keanekaragaman hayati di Indonesia serta untuk menjamin pembangunan yang berkelanjutan, pemerintah Indonesia telah berupaya melindungi keanekaragaman hayati dari kepunahan dengan beberapa cara yaitu melalui… Selengkapnya

Characterisation of Arabica Coffee Pulp - Hay from Kintamani - Bali as Prospective Biogas Feedstocks

The huge amount of coffee pulp waste is an environmental problem. Anaerobic fermentation is one of the alternative solutions. However, availability of coffee pulp does not appear for year-round, whereas biogas needs continuous feedstocks for digester stability. This research uses coffee pulp from Arabica Coffee Factory at Mengani, Kintamani, Bali–Indonesia. The coffee pulp was transformed into coffee pulp-hay product by sun drying for preservations to extend the raw materials through the year. Characterization of coffee pulp-hay was conducted after to keep for 15 mo for review the prospect as biogas feedstocks. Several parameters were analyzed such as C/N ratio, volatile… Selengkapnya

Metoda Pembuatan Monofilament Perak Superkonduktor

Invensi ini berupa suatu metoda pembuatan kawat monofilament perak superkonduktor dengan cara pemanasan dan roling yang dilakukan hingga 4 tahap pada material (Bi, Pb)-Sr-Ca-Cu-O dengan selubung tabung perak (Ag) dengan metoda PIT (Powder-In-Tube) melalui proses roling dan pemanasan 4 kali. Masing-masing pemanasan dilakukan didalam tungku listrik pada suhu 860C selama 24 jam dan dalam kondisi atmosfir udara. Suhu kritis onset (TCO) perak superkonduktor Ag/BPSCCO setelah melalui 4 tahap proses roling dan pemanasan adalah 115K. Nilai TCO ini naik dibandingkan proses roling dan pemanasan 3 kali yaitu 100K. Proses roling dan pemanasan yang berulang dapat meningkatkan nilai TCO pada kawat monofilament… Selengkapnya

Komunitas Makroalga di Perairan Tayando-Tam, Maluku Tenggara

Makroalga merupakan salah satu sumber daya bernilai ekonomis penting yang sangat potensial untuk dikembangkan untuk pangan maupun obat-obatan. Penelitian ini bertujuan untuk mengetahui struktur komunitas makroalga dengan mengkaji keanekaragaman, kepadatan, dominansi serta kondisi lingkungan perairannya. Penelitian dilaksanakan di perairan Tayando-Tam, Maluku Tenggara di lima stasiun pada bulan September 2015. Penelitian dilakukan dengan melakukan transek sepanjang 200 meter mulai dari pantai ke arah laut lepas, stasiun pengamatan dalam ukuran kuadran 50x50 cm. Komunitas makroalga di perairan Tayando-Tam secara umum masih dalam kondisi yang baik walaupun ada satu stasiun yang memiliki nilai dominasi sedang karena adanya faktor pembatas berupa arus. Makroalga yang… Selengkapnya

Formation of polycrystalline MgB2 synthesized by powder in sealed tube method with different initial boron phase

Magnesium diboride, MgB2 is a new high critical temperature superconductor that discovered in the beginning of the 21st century. The MgB2 has a simple crystal structure and a high critical temperature, which can be manufactured in several forms like thin films, tapes, wires including bulk in the large scale. For that reason, the MgB2 has good prospects for various applications in the field of electronic devices. In the current work, we have explored the synthesis of MgB2 polycrystalline using powder in a sealed tube method. Different initial boron phase for the synthesized of MgB2 polycrystalline were used. These were, in… Selengkapnya

ANALYSIS OF REQUIRED ELECTRIC POWER IN TUBE FURNACE USING DAQ MASTER PROGRAM

In order to design and develop DTA equipment, it is necessary to consider the selection of the appropriate heating elements. The coils resistor of 9, 16, and 23 ohm were used as heating elements to control the temperature in tube furnaces. The efficiency of tube furnaces were analyzed by operating them with electrical voltage of 22, 27, 31, 37, 47, 80 and 100 volt. The first tube furnace with heating element of 9 ohm could not be heated up to 1000°C due to low electric power. The second tube furnace with heating element of 16 ohm reached 1000°C when it… Selengkapnya