Preparation of proton exchange membrane by radiation-induced grafting method : Grafting of styrene onto poly(ethylene tetrafluoroethylene) copolymer films

Radiation induced grafting of styrene onto poly(ethylene-tetrafluoroethylene) (ETFE) copolymer film was carried out to prepare graft copolymer (ETFE-g-polystyrene) that can host sulfonic acid groups and form proton exchange membrane for polymer electrolyte fuel cell (PEFC). The effect of monomer concentration and type of solvent on the degree of grafting was investigated. The formation of graft copolymer film was confirmed by FTIR spectrum analysis

Variabilitas Harian Komunitas Ikan Padang Lamun Perairan Tanjung Tiram-Teluk Ambon dalam [Daily Variability Of Fish Community In Sea Grass Beds Of Tanjung Tiram-Inner Ambon Bay]

Penelitian ini dilaksanakan di perairan Tanjung Tiram , Teluk Ambon Dalam selama bulan Juli-Agustus 2012, untuk membandingkan kelimpahan dan struktur komunitas ikan padang lamun berdasarkan perbedaan siang dan malam hari. Ikan dikoleksi dengan metode sapuan menggunakan pukat pantai yang ditarik pada hamparan padang lamun sebanyak enam kali (masing-masing tiga kali mewakili siang dan malam hari). Hasil penelitian mendapatkan total jumlah individu ikan sebanyak 5593 individu dari 72 spesies dan 35 famili. Siganus canaliculatus mendominasi struktur komunitas ikan baik pada siang maupun malam hari, Ostorhinchus lateralis aktif pada malam hari, dan Aeoliscus strigatus yang aktif pada siang hari. Terdapat variasi struktur komunitas ikan antara siang dan malam, dengan nilai dominansi selalu lebih tinggi pada malam hari. Sebaliknya, keanekaragaman selalu tinggi pada siang hari dan keseragaman spesies lebih stabil pada siang hari. Variabilitas kelimpahan dan struktur komunitas ikan antara siang dan malam hari selain berkaitan dengan sifat nokturnal dan diurnal, juga dipengaruhi fluktuasi parameter oseanografi. Suhu, salinitas, oksigen terlarut, dan pH berpengaruh positif, sedangkan kekeruhan perairan berpengaruh negatif terhadap kelimpahan ikan di ekosistem padang lamun

The lethal concentration (LC50) of Zataria multiflora essential oil in fries of rainbow trout (Oncorhynchus mykiss)

This research was carried out to determine LC50 for Zataria multiflora essential oil in rainbow trout (Oncorhynchus mykiss) fries at 96 hours. In the process, we used the static O.E.C.D method for 180 rainbow trout fries weighing 5±1 grams in five treatments and one control with three replicates. During the experiments, the mean (±SD) of water temperature was kept at 16±1 C, dissolved oxygen (DO) was 7±0.2mg/l and pH was 8±0.4. We used 5- 25ppm of the essential oil and the results were analyzed using probit analysis procedure. The LC50 96h of Zataria multiflora essential oil was determined as 13.6ppm for rainbow trout (Oncorhynchus mykiss) fry. Based on the results, the useful maximum concentration of Zataria multiflora essential oil was less than 10ppm in rainbow trout fry. The results indicated a narrow therapeutic index for Zataria multiflore essential oil

Karakteristik Aspal Buton Ekstraksi yang Dimodifikasi dengan Oli Bekas dan Plastik HDPE

Asphalt functions as an aggregate binder in the road pavement mixture. The rapid construction of roads causes the need for asphalt to increase, while its availability is limited. The government is promoting the use of natural asphalt (Asbuton) as an alternative to oil asphalt. However, asphalt performance from Asbuton is not good. Uneven asphalt content and Asbuton hardness are factors causing it to be less effective as a binder. It is necessary to improve performance by modifying the bitumen separated from Asbuton granules by the extraction process. The modifications were made using used oil and high-density polyethylene (HDPE) plastic waste. Samples were made for each variation of used oil and HDPE in two ways: a constant 5% used oil composition and a constant 2% HDPE. In the constant 5% oil variation, 0%, 2%, 4%, and 6% HDPE are used. Whereas at a constant 2% HDPE, 0%, 3%, 5%, and 7% used oil are used. The tests carried out were: 1) Moisture content and ash content of asphalt extracted from Asbuton, 2) Penetration of asphalt, 3) Ductility; 4) Loss of weight, 5) specific gravity, 6) softening point, and 7) flash and burn points. The performance of modified asphalt is known from the results of data analysis from the tests carried out. The results of the analysis showed that in the asphalt weight loss test, specific gravity, and softening point, pure Asbuton extraction asphalt and the results of the modification as a whole met the requirements. However, in the penetration test, only 3 variations met the requirements, namely: 5% and 7% used oil, and 2% and 6% HDPE. Whereas in the ductility test, flash point, and burning point, all variations and asphalt extraction of pure Asbuton did not meet the requirements. Low ductility, meaning that asphalt does not have good cohesive properties. The low flash point and burning point indicate that the asphalt is easy and fast to burn, which affects the mixing process. Thus, it is still necessary to optimize the composition of the modifier so that the requirements for ductility, flash point, and firing point are met

A study of the anesthetic effect of Zataria multiflora Boiss (Labiatae) essence on Oncorhynchus mykiss and cultured Salmo trutta caspius

For the first time in the world, the effect of Zataria multiflora essence in concentrations of 50 and 100 ppm on Oncorhynchus mykiss fry weighing on average 15±2 g and cultured Salmo trutta caspius weighing on average 40±4 g was studied. The water temperature was 16-17 °C, dissolved oxygen was 7±0.2 and pH was 8 during the investigation. O. mykiss and S. trutta caspius reached complete sedation during an average time of 3 and 2 minutes respectively in the two concentrations. The mean balance and recovery time were 2 and 3 minutes respectively. Results showed that the sedation and recovery time are significantly different in the two species and with the two concentrations of the sedative (P<0.05). The research also showed that Z. multiflora essence has an anesthetic effect on the two species, but because of the unwanted severe irreparable breathing side effects and the accompanied body deformation of the two species, the essence is not suggested as an anesthetic for the fish. The essence is not recommended as a general anesthetic, but it may be used in 15-20ppm as a sedative during manipulation of the fish

The Composition of Species and Structure of Seagrass Fish Community in Tanjung Tiram – Inner Ambon Bay

The study was conducted in March - May 2011 in the coastal waters of Tanjung Tiram – inner Ambon bay. The aims of the study were to determine the composition of species and structure of fish communities in seagrass beds ecosystems. Fish were collected every spring and neap tide for three month periode with a swept area method using beach seine. Fishes were collected as many as 6444 individuals representing 68 species from 29 families. Siganus canaliculatus was contributed up to 62.91% of the total individual fish found.The fish community structure was varied between spring and neap tide. Index of dominance was in low category, diversity in medium, and evenness in unstable conditions. Moreover, the results indicated that seagrass ecosystems in Tanjung Tiram (TAD) have an important role as spawning, nursery ground, and feeding ground. Therefore, management and conservation efforts are urgently needed to maintain the ecological role of seagrass ecosystems for the sustainability of the fish resources

Detection and distribution of virulence genes in Aeromonas hydrophila isolates causing infection in cultured carps

Aeromonas hydrophila is a bacterium associated with many diseases and disorders such as fin rot, skin ulcers and lethal hemorrhagic septicemia in fish. It bears several virulence factors including type III secretion system (T3SS), aerolysin, cytolytic enterotoxin and enzymes (e.g., hemolysins, lipase) that seem to play an important role in its pathogenesis. Detection of virulence markers by polymerase chain reaction (PCR) is a key procedure in defining the pathogenic ability of pathogenic bacteria and preparing a vaccine for its treatment. In this sense, this study was aimed to determine the frequency of virulence genes in isolates obtained from infected cultured carps in Khuzestan province. Out of 200 moribund carps with septicemic symptoms, 125 isolates were belonged to the motile aeromonads and 59 isolates were identified as A. hydrophila by biochemical methods. Finally, using PCR analysis, 31 isolates were identified as A. hydrophila. Five virulence genes were detected in these isolates including hemolysin, aerolysin, cytolytic enterotoxin and T3SS (aopB and ascV) by specific primers. Results showed that 23 (74.19%), 18 (58.06%), 16 (51.61%), 13 (41.63%) and 10 (32.25%) isolates possessed cytolytic enterotoxin, hemolysin, aerolysin, and T3SS genes, respectively. The results of the present study showed that among 31 isolates, only five isolates had all of dominant virulence genes. Thirteen other isolates had genotypes including hlyA+, aerA+, and act+. The remaining isolates had at least one virulence gene. This study showed that determination of the virulence genes by PCR can be a reliable method to identify a potential pathogenic Aeromonad strain