Pengaruh Posisi Peletakan Katup Buang Terhadap Kinerja Pompa Hidram

AbstrakAir merupakan salah satu faktor kebutuhan pokok yang sangat penting dan tidak bisa dipisahkan dalam kehidupan manusia dan mahluk hidup lainnya. Air juga sebagai sumber kehidupan yang sangat di butuhkan baik diperkotaan maupun di perdesaan khususnya masyarakat yang belum terjangkau listrik dan kesulitan dalam memperoleh air bersih dan memperoleh air bersih harus menempuh perjalanan yang jauh.Penelitian ini menggunakan metode eksperimen. Teknik analisa data dalam penelitian ini menggunakan analisis data statistika deskriptif kuantitatif yaitu menggambarkan hasil penelitian secara grafis dalam table dan grafik. Penelitian ini dilakukan untuk mengetahui pengaruh posisi peletakan katup buang terhadap kinerja pompa hidram. Pompa hidram yang digunakan pada penelitian ini memiliki diameter pipa inlet 1 inchi, dengan sudut 45º dan panjang 4 m dan diameter pipa discharge 0,5 inchi, panjang 4 m dengan menggunakan volume tabung udara 0,0028 m3, sedangkan variasi posisi peletakan katup buang adalah 5 cm, 10 cm , 20 cm. Hasil penelitian ini diperoleh bahwa pada perancangan pompa hidram didapatkan hasil yang paling optimal adalah pada jarak 10 cm dengan ketinggian inlet 1,75 meter, volume tabung udara 0,0028 m3 dan ketinggian discharge 4 m. Dengan kapasitas discharge sebesar 1,41 liter/menit, efisiensi pompa 38,17%. Sedangkan efisien terendah yaitu pada jarak 20 cm, dengan nilai efisiensi sebesar 34,07% dan kapasitas discharge 1,39 liter/menit. Kata Kunci : Pompa Hidram, peletakan katup Buang, Kapasitas discharge, Efisiensi.AbstractWater is one of the most important and inseparable inseparable in human life also other living things. Water is also a source of life that is needed both in cities and rural areas. Especially, people who have not been reached by electricity and difficulties in obtaining clean water with long distances. The research is using experimental method. The data analysis technique this study use quantitative descriptive statistical, which graphically describes the results of research in tables and graphs. The research was conducted to determine the effect of the position the exhaust valve on the performance hydraulic pump. Hydram pump used this research has a diameter of 1 inch inlet pipe, with an angle of 45º and a length of 4 m and a discharge pipe diameter of 0.5 inches, a length of 4 m using the air tube volume 0.0028 m3, while the variation of the position of the exhaust valve is 5 cm, 10 cm, 20 cm. The results of this research indicate that the design of the hydraulic pump most optimal results is at a distance of 10 cm with an inlet height of 1.75 meters, air tube volume 0.0028 m3 and discharge height of 4 m. With a discharge capacity of 1.41 liters / minute, pump efficiency is 38.17%. While the lowest efficient is at a distance of 20 cm, with an efficiency value of 34.07% and a discharge capacity of 1.39 liters / minuteKeywords: Hydram pump, laying of discharge valve, discharge capacity, efficiency

Cytotoxic effect of betulinic acid and betulinic acid acetate isolated from Melaleuca cajuput on human myeloid leukemia (HL-60) cell line

The cytotoxic effect of betulinic acid (BA), isolated from Melaleuca cajuput a Malaysian plant and its four synthetic derivatives were tested for their cytotoxicity in various cell line or peripheral blood mononuclear cells (PBMC) by 3-[4,5-dimethylthizol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Betulinic acid acetate (BAAC) was most effective than other betulinic acid derivatives. It had most active cytotoxic activity against human myeloid leukemia (HL-60), human T4-lymphoblastoid (CEM-SS), BALB/c murine myelomonocytic leukemia (WEHI-3B) and human cervical epithelial carcinoma (HeLa) but not on normal human lymphocytes (PBMC), suggesting its action is specific for tumor cells. BA and BAAC inhibit HL-60 cell line at low concentration after 72 h with IC50 values at 2.60 and 1.38 g/mL, respectively. DNA fragmentation analysis showed ladder formation in the 100 - 1500 bp region in HL-60 cell lines after 24 h of treatment with IC50 values. The induction of apoptosis was also confirmed by flow cytometric analysis of cell cycle. BA and BAAC have been shown to induce a time dependant increase in the sub G1 peak indicating apoptotic phenomenon as obtained from the DNA content histogram analysis. Thus, betulinic acid isolated from Malaysia plant showed good potential as an anti-cancer compound with less toxicity to human normal cells.Key words: Betulinic acid, HL 60, cytotoxicity, MTT assay, DNA laddering, Cell cycle P