Heavy landings of juveniles of Indian scad, Decapterus russelli at Munambam Fisheries Harbour

Among the carangid fishes, the Indian scad, Decapterus russelli is an important pelagic fish and a major commercial species contributing to the marine fisheries of Kerala. The fish is locally called “kozhuchala” and it forms a regular fishery. The species is often caught as by-catch in shrimp trawl nets having cod-end mesh sizes ranging from 15 mm to 20 mm that is operated in the depth range of 55- 90 m almost throughout the year. They are consumed fresh as well as sun dried form

Desain Sucker Rod Pump Untuk Optimasi Produksi Sumur Sembur Alam L5a-x Di Pertamina Ep Asset 2 Field Limau

Sumur yang terus berproduksi akan mengalami penurunan tekanan reservoir dan akibatnya produktifitas sumur menurun, maka perlu ditambah tekanan agar fluida dapat mengalir ke permukaan, yaitu melalui metode pengangkatan buatan (artificial lift)[1]. Dalam perencanaannya dapat dilakukan dengan analisis kualitatif dan analisis kuantitatif (perhitungan) berupa besarnya laju produksi sumur. Penurunan produksi yang terjadi pada sumur sembur alam L5A-X struktur Niru hanya mencapai 41,67 BOPD [2]. Oleh sebab itu dibutuhkan metode pengangkatan buatan agar sumur dapat berproduksi secara optimal. Metode artificial lift yang dipilih adalah menggunakan sucker rod pump. Pemilihan alat ini dilakukan berdasarkan laju produksi sumur yaitu, melalui analisis kurva inflow performance relationship (IPR). Dari hasil análisis kurva IPR sumur L5A-X struktur Niru masih produktif untuk menghasilkan fluida yaitu sebesar 594,12 BFPD. Untuk merencanakan setiap komponen-komponen pompa maka dilakukan perhitungan secara teoritis. Hasil perhitungan optimasi pompa untuk sumur L5A-X jenis pompa yang digunakan adalah tipe pompa Tubing Heavy Wall Barrel (TH). Parameter pemilihan pompa, yaitu diameter plunger sebesar 2 ¼ in dan diameter tubing 2 7/8 in. Dengan merencanakan kecepatan pemompaan 7 SPM, panjang langkah pemompaan 144 inch dan kombinasi ukuran rod yang akan dipakai, yaitu ¾ in, 7/8 in, 1in maka, diperoleh laju produksi sebesar 578,62 BFPD. Dapat disimpulkan metode yang efektif untuk sumur produksi L5A-X adalah metode artificial lift dengan menggunakan sucker rod pump

Marine microlalgal culture

Marine microlalgal cultur

Prospek Proyek Pembukaan Pemboran Sumur Minyak X Pada Lapangan X PT Pertamina Ep Asset 2 Field Prabumulih

PT Pertamina adalah sebuah Perusahaan yang bergerak dibidang perminyakan dan pergasan. Pengelolaan kontraknya dengan pemerintah dengan cara kontrak bagi hasil. Investasi untuk menemukan minyak atau gas di dalam bumi sampai siap berproduksi memerlukan dana atau investasi yang sangat besar, sehingga sebelum investasi tersebut dilakukan harus dikaji dulu apakah investasi tersebut prospek atau tidak untuk dilakukan. Jika investasi tersebut prospek maka dilakukan proyek investasi (go), jika tida maka tidak dilakukan (no go). Dalam analisa ekonomi ada 4 cara penilian atau kriteria untuk menilai apakah investasi tersebut prospek atau layak, yaitu : pay out time (POT), net present value (NPV), rate of return (ROR), dan profit to investment ratio (PIR). Semakin pendek payback period, maka investasi sangat prospek atau layak dilaksanakan, apabila NPV positif menunjukan investasi prospek atau layak, apabila ROR lebih besar dari interest rate yang ada menunjukkan investasi prospek atau layak dan apabila profit to investment ratio besar dari 1 maka ini juga menunjukkan investasi prospek atau layak. Dari analisa ekonomi yang dilakukan terhadap rencana PT Pertamina melakukan pemboran sumur X didapat angka-angka sebagai berikut : pay out time (POT) 2,54 tahun, NPV positif sebesar $ 2.952.513, ROR 20,82 %, dan profit to investment ratio 2.45, sehingga investasi ini dinilai prospek dan dapat dilaksakan

Copepod Abundance and Diversity from Offshore Region of Tuticorin, South East Coast of India

A detailed study had been carried out on species abundance, biomass and composition of copepod in four different offshore stations namely, Station I: Vembar, II: Keelavaipar, III: Punnaikayal and IV: Thiruchendhur in Gulf of Mannar region from October 2011 to April 2012. A total of 56 copepod species belongs to 20 families under 4 orders have been encountered during the period. The percentage composition of different groups of copepod species was composed of Calanoida (35 numbers) 62.5%, Cyclopoida (4 numbers) 7.14%, Harpacticoida (8 numbers) 14.3% and Poecilostomatoida (9 numbers) 16.1%. The percentage of biomass composition of different groups of copepods during the study was in the order of Calanoida 38.99%, Harpacticoida 32.56%, Cyclopoida 15.22% and Poecilostomatoida 13.23%. In the case of species composition, Euterpina acutifrons (28.61%) was the most abundant species followed by Acrocalanus gracilis (17.68%), Corycaeus crassiusculus (12.33%), Oithona brevicornis (12.03%) and Temora turbinata (4.25%) were the other dominant species in observation. The copepod density in different stations were in the range of 8600–39900, 3900–64600, 3800–24800 and 5000–22500 numbers m-3 at station I, II, II and IV respectively. The lowest biomass of copepod was observed at station III and highest biomass was found at station II. The copepod species richness ranged from 0.48 to 2.72 and species diversity was in the range of 0.87 to 1.98 in the study areas. Species evenness was varied from 0.24 – 0.51 during the observation period

Adoption of Sea Cage, Culture Practices in Thoothukudi District Tamil Nadu: An Eye Opener for Income Generation

Adoption of Sea Cage, Culture Practices in Thoothukudi District Tamil Nadu: An Eye Opener for Income Generatio

Immunomodulation and interferon gamma gene expression in sutchi cat fish, Pangasianodon hypophthalmus: effect of dietary fucoidan rich seaweed extract (FRSE) on pre and post challenge period

A 45-days feeding trial was conducted to study the immunomodulatory effect and interferon gamma gene expression of dietary fucoidan rich seaweed extract (FRSE) from Sargassum wightii on Pangasianodon hypophthalmus fingerlings. One hundred and eighty fingerlings were distributed into six experimental groups in triplicates. Each group was stocked with 10 fish and fed to satiation with iso-nitrogenous (34.96 � 0.09–35.18 � 0.03 CP%) and iso-caloric (368.65 � 0.86–375.09 � 0.26 Kcal/100 g) purified diets containing either 0% FRSE (control), 1% FRSE (TF1), 2% FRSE (TF2), 3% FRSE (TF3), 3% seaweed powder (TS3) or 6% seaweed powder (TS6) in the feed. After feeding trial the experimental fish were challenged with Aeromonas hydrophila. Immunological parameters like respiratory burst activity, lysozyme activity, phagocytic activity and total leukocyte count (TLC) were increased with the increasing level of dietary FRSE, whereas serum Albumin/ Globulin (A/G) ratio and blood glucose level exhibited decreasing trend (P < 0.05)

Evaluation of the Quality of Commercial Fish Feeds in India with Respect to Microbiological Parameters

This paper describes the first comprehensive study of the quality of commercial fish feeds in India with regard to microbiological indices. Quality of feed is an important parameter that has a direct impact on the outcome of any aquaculture system. Microbiological parameters such as total plate count (TPC), Escherichia coli (CFUg-1), coliformes (CFUg-1), Enterobacteriaceae (CFUg-1) and yeast and mould (CFUg-1) counts were analysed using 3M™ Petrifilm™ as per guidelines. The TPC ranged from 2.0 × 102 to3.13 × 104 CFUg-1 in different feeds. Presence of E. coli was detected in one of the feeds with 1.15×102 CFUg-1. Coliform bacteria were not detected in any of the feeds. Enterobacteriaceae was present in three feeds in the range of 5.45 × 102 to 1.58×103 CFUg-1. Yeast and mould count ranged from <10 to 1.68 × 104 CFUg-1 in the feeds analyzed. The results obtained from the present study indicate that the feeds were contaminated with micro-organisms. As far as Indian scenario is concerned, there exist several feed companies which do not comply with the quality regulations and specifications as laid down by the Bureau of Indian Standards (BIS). In addition, specifications are not available for aqua feeds regarding the acceptable levels of microbiological parameters. Hence the present study calls for a standardized code of quality to be observed by feed manufacturing companies for quality products

A new layout optimization technique for interferometric arrays, applied to the MWA

Antenna layout is an important design consideration for radio interferometers because it determines the quality of the snapshot point spread function (PSF, or array beam). This is particularly true for experiments targeting the 21 cm Epoch of Reionization signal as the quality of the foreground subtraction depends directly on the spatial dynamic range and thus the smoothness of the baseline distribution. Nearly all sites have constraints on where antennas can be placed---even at the remote Australian location of the MWA (Murchison Widefield Array) there are rock outcrops, flood zones, heritages areas, emergency runways and trees. These exclusion areas can introduce spatial structure into the baseline distribution that enhance the PSF sidelobes and reduce the angular dynamic range. In this paper we present a new method of constrained antenna placement that reduces the spatial structure in the baseline distribution. This method not only outperforms random placement algorithms that avoid exclusion zones, but surprisingly outperforms random placement algorithms without constraints to provide what we believe are the smoothest constrained baseline distributions developed to date. We use our new algorithm to determine antenna placements for the originally planned MWA, and present the antenna locations, baseline distribution, and snapshot PSF for this array choice.Comment: 12 pages, 6 figures, 1 table. Accepted for publication in MNRA

Nutritional evaluation of protein isolate from rubber seed in the diet of Labeo rohita: Effects on growth performance, nutrient utilization, whole body composition and metabolic enzymes activity

A 45-days feeding trial was conducted to study the immunomodulatory effect and interferon gamma gene expression of dietary fucoidan rich seaweed extract (FRSE) from Sargassum wightii on Pangasianodon hypophthalmus fingerlings. One hundred and eighty fingerlings were distributed into six experimental groups in triplicates. Each group was stocked with 10 fish and fed to satiation with iso-nitrogenous (34.96 � 0.09–35.18 � 0.03 CP%) and iso-caloric (368.65 � 0.86–375.09 � 0.26 Kcal/100 g) purified diets containing either 0% FRSE (control), 1% FRSE (TF1), 2% FRSE (TF2), 3% FRSE (TF3), 3% seaweed powder (TS3) or 6% seaweed powder (TS6) in the feed. After feeding trial the experimental fish were challenged with Aeromonas hydrophila. Immunological parameters like respiratory burst activity, lysozyme activity, phagocytic activity and total leukocyte count (TLC) were increased with the increasing level of dietary FRSE, whereas serum Albumin/ Globulin (A/G) ratio and blood glucose level exhibited decreasing trend (P < 0.05)