Judul: Performance analysis of Seaweed Gracilaria gigas at Sea and Ponds Cultivated System in West Nusa Tenggara Barat
Abstrak: Gracilaria gigas is a low level plants which does not have tree roots, stems and leaves of true, but in the form of thallus branching, and live in the sea with a depth that can still be reached by sunlight. G. gigas is one of seaweed species the from red algae type (Rhodophyceae) producsy agarofit, G. gigas have the high fiber and good for health. Thei research aims to analyze the performance of production, yield and quality of G. gigas seaweed cultivated in the sea and in the ponds. The cultivation of G. gigas in ponds was held in Sekotong, west Lombok by broadcast method in 1500 m2 planting area. While cultivation in the sea was held in Gerupuk Bay, Central Lombok by Long-line method the 1250 m2 planting area. Average productivity of G. gigas cultivated in the sea 12.72%, while in ponds 4.00%. the was seaweed yield cultivation in ponds reached 18, 53%, and in marine aquaculture reached 6.85%, while the quality that the gel strength of G. gigas cultured in ponds was 18.46%, and in the sea reached 7.54%. the yield and gel stregh were positively correlated with N waters and branching index. Cultivation of G. gigas in the sea with long-line method in order to produce a yield of 6.85%, 7.54% and gel strength, whereas in the stocking ponds with methods that produce a yield of 18.53%, 18.46% and gel strength. The quality of the cultivated seaweed in the ocean negatively correlated with salinity (0.87), while the cultivation in ponds negatively correlated with nitrate (0.85) and ammonia (0.95), and positively correlated with brightness (0.91) and phosphate (0.66). The branching index seaweed cultivated at the sea rods closely related salinity to approximately 87%. Seaweed cultivation in ponds shared negative associated between branching index and brightness (91%), and phosphate (66%), oxygen (62 %). Otherwise parameters associated negatively were branching index and ammonia (95%), o nitrate (85%).
Keyword: seaweed culture, Gracilaria gigas, branching index, seaweed quality, dan productivity

Judul: Potency of seaweeds aquaculture Kappaphycus alvarezii and Gracilaria gigas in carbon sequestration
Abstrak: Carbon sequestration by algae as photoautotrophic organism is potential to reduce CO2 released to the atmosphere, and support to reduce the inclination of global warming. The aim of this study was to analyzed the level of carbon sequestration by seaweed aquaculture of Kappaphycus alvarezii and Gracilaria gigas based on photosynthesis activity included influential variabels, and also analyzed potency of carbon sequestration by seaweed aquaculture area. Seaweed cultivation was conducted at Gerupuk Bay, Central Lombok, West Nusa Tenggara on long-line system with culture area of 2.500 m2. The seaweeds and sea water parameters were analysed on days-0, 10, 20, 30 and 45. Seaweeds parameters was observed included daily growth rate, carbon absorption rate, carbohydrate production, photosynthesis pigment content, aquaculture productivity, and branching index. Water quality parameters was analyzed included temperature, salinity, dissolved oxygen, pH, total dissolved solid, total CO2, NO3-N, NO2-N, NH3-N, PO4-P, transparency and current velocity. Total rate of carbon sequestration based on biomass seaweeds harvesting at the end of cultivation that showed G. gigas (20,67 ton C/ha/year) was almost 335,79% higher than K. alvarezii (90,09 ton C/ha/year), and also higher daily growth rate, carbohydrates production, and photosynthesis rate that supported by higher branching index. The rate of carbon absorption by seaweeds had the highest positive correlation with pigment content as internal factor of seaweeds, as well as water transparency as external factor. Potency of carbon sequestration by seaweeds aquaculture area in Gerupuk Bay reached 6.656,51 tons C/year or 0,36 ton C/ton biomass for K. alvarezii; and 29.008,53 tons C/year or 0,58 ton C/ton biomass for G. gigas cultivation. High potency of carbon sequestration of seaweeds aquaculture could be an alternative of sustainable seaweed aquaculture management. Strategy of seaweeds cultivation might applied based on the highest carbon absorption rate on days 0 – 20 by getting rejuvenation, so that more effective in carbon sequestration as well as increasing of seaweed aquaculture productivity.
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Judul: Transisi Fasa Materi Hadronik ke Materi Kuark pada Inti Bintang Neutron.
Abstrak: Bintang neutron terdiri dari beberapa lapisan yang disusun oleh materi nuklir yang berbeda dengan kerapatan yang semakin tinggi ketika mendekati pusat bintang. Inti luar bintang neutron disusun oleh materi hadronik (nukleon, lepton, dan hyperon), sedangkan inti dalam bintang neutron disusun oleh kuark-kuark bebas (up, down, strange) yang saling berinteraksi. Tujuan penelitian ini adalah mempelajari bagaimana transisi dari inti luar ke inti dalam bintang neutron dengan menggunakan pendekatan RMF (Relativistic Mean Field) untuk materi hadronik dan CIDDM (Confined Isospin Density Dependent Mass) untuk materi kuark. Tekanan transisi diperoleh ketika potensial kimia barion materi hadronik dan materi kuark bernilai sama. Nilai tekanan transisi dengan parameter SU6-TM1 sekitar 87 MeV/fm3 dan diperoleh massa maksimum bintang neutron yaitu 1.92M dengan jari-jari sekitar 8.62 km. Nilai tekanan transisi dengan parameter SU6-G2 sekitar 53 MeV/fm3 dan massa maksimum bintang neutron yaitu 1.88M dengan jari-jari sekitar 8.16 km. Jenis transisi fasa adalah orde satu ditandai dengan diskontinuitas dalam kerapatan energi (adanya mixed phase). Parameter-parameter pada model nuklir yang digunakan menyebabkan perbedaan kekakuan persamaan keadaan (EOS) dari materi hadronik dan materi kuark sehingga nilai tekanan transisi dari fasa hadronik ke fasa kuark juga berbeda.
Keyword: bintang neutron, persamaan keadaan, transisi fasa