LSFT0A2

Exam paper (Unit 1-6) for first semester 201

LSFT0B2

Exam paper (Unit 1-6)for second semester 201

ANALISA UNJUK KERJA LOW PRESSURE HEATER UNIT#1 6 DENGAN METODE EFFECTIVENESS - NTU PLTU I JAWA TIMUR PACITAN PADA BEBAN 200 MW ( PERFORMANCE ANALYSIS OF LOW PRESSURE HEATER UNIT#1 6 USING EFFECTIVENESS – NTU PLTU I JAWA TIMUR PACITAN ON 200 MW LOAD )

Alat penukar panas merupakan suatu komponen yang sangat penting dalam suatu industri yang melibatkan proses transfer panas seperti pembangkit listrik. Pembangkit listrik mempunyai alat penukar panas yang dapat melakukan proses transfer. Salah satunya adalah unit Low Pressure Heater. Low Pressure Heater merupakan alat penukar panas bertipe Shell and Tube dengan susunan pipanya berupa Pipa U. PLTU 1 Jawa Timur terdiri dari 2 unit yang beroperasi memasang masing – masing 4 unit Low Pressure Heater, yaitu Low Pressure Heater 7-8, Low Pressure Heater 6 dan Low Pressure Heater 5. Tujuan dari penulisan tugas akhir ini adalah untuk mengetahui unjuk kerja dari salah satu Low Pressure Heater tersebut atau tepatnya pada Low Pressure Heater Unit#1 6. Dengan menggunakan metode kalkulasi dan effectiveness – NTU, akan diketahui seberapa besar efektivitas yang diberikan oleh Low Pressure Heater Unit#1 6 tersebut. Penulis membatasi analisa alat penukar panas ini ketika unit 1 PLTU 1 Jawa Timur Pacitan beroperasi pada beban 200 MW. Proses perhitungan menggunakan metode kalkulasi dan metode effectiveness – NTU menghasilkan nilai effectiveness sebesar 0,94 sehingga Low Pressure HeaterUnit#1 6 masih menunjukkan kinerja yang maksimal. Kata Kunci : Shell and Tube, Alat Penukar Panas, Low Pressure Heater, Effectiveness, NTU Heat Exchanger is an important component in the field of industries which brought some heat trasnfer’s processe like a power plant. A power plant has many heat exchanger which brought process transfer. One of them is Low Pressure Heater. Low Pressure Heater is a Shell and Tube heat exchanger with U-Pipe pipping structure inside the heater. PLTU 1 Jawa Timur Pacitan which has 2 operational units set 4 units of Low Pressure Heater. There are Low Pressure Heater 7-8, Low Pressure Heater 6 and Low Pressure Heater 5 in each operational unit. The purpose of this thesis is for knowing the performance of one of the low pressure heater, for exactly Low Pressure Heater Unit#1 6. Using two methodes, Calculation Methode and Effectiveness – NTU methode, the writer will know the effectiveness which given by this low pressure heater. The writer also limit the performance analysis of Low Pressure Heater when unit 1 of PLTU 1 Jawa Timur Pacitan operate on 200 MW load. Measurement process used both calculation methode and effectiveness – NTU methode give effectivenes value as 0,94 therefor Low Pressure HeaterUnit#1 6 still has maximal quality. Keywords : Shell and Tube, Heat Exchanger, Low Pressure Heater, Effectiveness, NT

Deep EST profiling of developing fenugreek endosperm to investigate galactomannan biosynthesis and its regulation

Galactomannans are hemicellulosic polysaccharides composed of a (1 → 4)-linked β-D-mannan backbone substituted with single-unit (1 → 6)-α-linked D-galactosyl residues. Developing fenugreek (Trigonella foenum-graecum) seeds are known to accumulate large quantities of galactomannans in the endosperm, and were thus used here as a model system to better understand galactomannan biosynthesis and its regulation. We first verified the specific deposition of galactomannans in developing endosperms and determined that active accumulation occurred from 25 to 38 days post anthesis (DPA) under our growth conditions. We then examined the expression levels during seed development of ManS and GMGT, two genes encoding backbone and side chain synthetic enzymes. Based on transcript accumulation dynamics for ManS and GMGT, cDNA libraries were constructed using RNA isolated from endosperms at four ages corresponding to before, at the beginning of, and during active galactomannan deposition. DNA from these libraries was sequenced using the 454 sequencing technology to yield a total of 1.5 million expressed sequence tags (ESTs). Through analysis of the EST profiling data, we identified genes known to be involved in galactomannan biosynthesis, as well as new genes that may be involved in this process, and proposed a model for the flow of carbon from sucrose to galactomannans. Measurement of in vitro ManS and GMGT activities and analysis of sugar phosphate and nucleotide sugar levels in the endosperms of developing fenugreek seeds provided data consistent with this model. In vitro enzymatic assays also revealed that the ManS enzyme from fenugreek endosperm preferentially used GDP-mannose as the substrate for the backbone synthesis