Hasil Pencarian  ::  Simpan CSV :: Kembali

Hasil Pencarian

Ditemukan 2790 dokumen yang sesuai dengan query
cover
Tooley, Peter
London: John Murray, 1971
665 TOO f
Buku Teks SO  Universitas Indonesia Library
cover
Mehlenbacher, V.C.
Illinois: Garrad Press, 1960
613.28 MEH a
Buku Teks SO  Universitas Indonesia Library
cover
O,Brien, Richard D.
Boca Raton: CRC Press, 2009
664.3 OBR f
Buku Teks  Universitas Indonesia Library
cover
Cyntiani
"Asam lemak adalah salah satu komponen penyusun minyak lemak. Komposisi asam lemak dalam minyak lemak berbeda satu dengan yang lain. Analisis dengan kromatografi gas secara langsung akan membutuhkan waktu analisis yang lama karena titik didih asam lemak yang sangat tinggi sehingga perlu dilakukan derivatisasi sebelum dianalisis. Penelitian ini bertujuan untuk memperoleh kondisi analisis optimum asam laurat, asam oleat, dan asam palmitat agar diperoleh metode yang valid yang selanjutnya digunakan untuk menetapkan kadar minyak lemak dalam produk obat gosok. Derivatisasi dilakukan dengan metode esterifikasi Lepage menggunakan reagen metanol-toluen 4:1 (v/v) dan katalis asetil klorida. Analisis dilakukan menggunakan kromatografi gas dengan kolom VB-wax (60 m x 0,32 mm), suhu kolom terprogram 170-190°C, kenaikan 20C/menit dan dipertahankan selama 3 menit. Suhu injektor dan suhu detektor masing-masing 230 dan 250°C; laju alir gas helium 1,2 ml/menit, volume penyuntikan 1,0 μl, dan dideteksi dengan detektor ionisasi nyala. Pada kondisi optimum waktu retensi laurat termetilasi adalah 4,32 menit dengan faktor ikutan 1,36. Waktu retensi palmitat termetilasi adalah 6,723 menit, faktor ikutan 1,32. Waktu retensi oleat termetilasi adalah 9,789 menit, faktor ikutan 1,44. Metode yang diperoleh valid dengan presisi (KV) antara 0,11-0,36%, dan uji perolehan kembali 98,22-102,00%. Sampel A mengandung minyak kelapa dengan kadar rata-rata 49,95% , sampel B mengandung minyak zaitun dengan kadar rata-rata 18,99% , sampel C tidak mengandung minyak lemak.

Fatty acid is one of the components that builds up the structure of lipid such as fat and oils. Each fatty acid composition present in lipid is different with one and another. Direct analysis performed by means of gas chromatography will require longer analysis time due to relatively high melting point of fatty acids hence derivatization is to be conducted in advance. This research was performed to achieve optimum analytical condition in order to obtain valid method which is required for subsequent determination of fatty acid contents present in liniment products. Derivatization was conducted by Lepage esterification using reagent such as methanol-toluene 4:1 (v/v) and acetyl chloride which was served as catalyst. On the other hand, the analysis process was done by gas chromatography using VB-wax column (60m x 0.32mm), the temperature of the column was set at 170-190°C with the increase of 2°C and was kept for 3 minutes. The temperature of injector and detector were 230 and 250°C, respectively; the flow rate of helium was 1.2 ml/minute with 1.0μl injection volume and detected by flame ionization detector. At the optimum condition, the retention time of methylated lauric and palmitic were 4.32 minutes with tailing factor of 1.36 and 6.723 minutes with tailing factor of 1.36, respectively. Meanwhile, the retention time required for methylated oleic was 9.789 minutes tailing factor of 1.44. The acquired method was valid within precision (CV) of 0.11-0.36%, and the approximate result of recovery test was 98.22-102.00%. The average content of coconut oil in sample A was 49.95%, the average content of olive oil in sample B was 18.99 %, meanwhile sample C had no fatty oil."
Depok: Fakultas Matematika dan Ilmu Pengetahuan Alam Universitas Indonesia, 2012
S42820
UI - Skripsi Open  Universitas Indonesia Library
cover
Houston: The Society of Exploration Geophysicists,
665 TLE
Majalah, Jurnal, Buletin  Universitas Indonesia Library
cover
New York: Wiley, 1996
R 665 BAI
Buku Referensi  Universitas Indonesia Library
cover
New York: John Wiley & Sons, 1996
R 664.3 BAI
Buku Referensi  Universitas Indonesia Library
cover
New York: John Wiley & Sons, 1996
R 664.3 BAI
Buku Referensi  Universitas Indonesia Library
cover
Maria Wulandari
"Pada penelitian ini, telah dibuat gemuk bio food grade berbasis turunan minyak kelapa sawit menggunakan thickener sabun kalsium kompleks, yang merupakan campuran sabun Ca-asetat dan Ca-hidroksi stearat dengan variasi rasio mol sabun Ca-asetat/Ca-hidroksi stearat = (0-6). Gemuk tersebut dibuat dengan tahapan saponifikasi di reaktor batch tertutup skala pilot (5kg), pendinginan di crystalizer dan homogenisasi di homogenizer. Parameter uji pelumas gemuk yang dilakukan yaitu uji dropping point (ASTM D-566), uji penetrasi (ASTM D-217), dan uji anti aus four ball (ASTM D-4172). Gemuk terbaik yang dihasilkan memiliki dropping point 324ºC, pada rasio mol Ca-asetat/Ca-hidroksi stearat 5:1.

In this research, bio food grade grease based on derivative of palm oil by using calcium complex soap as thickening agent is synthesized. Grease thickener is a mixture of Ca-acetate and Ca-hydroxy stearate with mol ratio Ca-acetate/Cahydroxy stearate (0-6). Grease is synthesized in pilot scale closed batch reactor (5 kg), continued by cooling in crystalizer, and homogenizing in homogenizer. Grease performance tests done on greases in this research are dropping point test (ASTM D-566), penetration test (ASTM D-217), and four ball anti wear test (ASTM D-4172). The best grease product is resulted from mol ratio Caacetate/Ca-hydroxy stearate 5:1."
Depok: Fakultas Teknik Universitas Indonesia, 2009
S52179
UI - Skripsi Open  Universitas Indonesia Library
cover
Silitonga, Frans Putra Negara
"ABSTRAK
Omega-3, omega-6, dan omega-9 adalah jenis asam lemak tidak jenuh rantai panjang. Senyawa ini banyak dibutuhkan untuk mencegah terjadinya kolesterol pada tubuh manusia. Analisis dengan kromatografi gas secara langsung akan membutuhkan waktu analisis yang lama karena titik didih asam lemak yang sangat tinggi sehingga perlu dilakukan derivatisasi sebelum dianalisis. Penelitian ini bertujuan agar memperoleh metode yang valid untuk selanjutnya digunakan pada menetapkan kadar omega-3, omega-6, dan omega-9 dalam produk minyak goreng. Derivatisasi dilakukan dengan metode esterifikasi Lepage menggunakan reagen metanol-toluen 4:1(v/v) dan katalis asetil klorida. Analisis dilakukan menggunakan kromatografi gas dengan kolom CBP-10 (60m x 0,32mm), suhu kolom terprogram 200-230ºC, kenaikan 2ºC/menit, dipertahankan selama 20 menit. Suhu injektor dan suhu detektor masing-masing 230 dan 250oC; laju alir gas helium 1,40 ml/menit, volume penyuntikan 1,0 µl, dan dideteksi dengan detektor ionisasi nyala. Diperoleh waktu retensi omega-3 16,445 menit, omega-6 15,922 menit, dan omega-9 15,820 menit. Uji presisi menunjukkan hasil yang baik dengan kv omega-3, omega-6 dan omega-9 berturut-turut sebesar 1,1022%, 1,22%, dan 0,547%. Uji perolehan kembali berturut-turut sebesar 98,60%, 99,12%, dan 98,83%. Hasil uji sampel A, B, dan C diperoleh berturut-turut omega-9 sebesar 99,82%, 99,29%, 84,05% dan menunjukkan tidak adanya omega-3 dan omega-6.

ABSTRAK
Omega-3, omega-6 and omega-9 are unsaturated long chain fatty acids. These compounds are needed to prevent the occurrence of cholesterol in the human body. Analysis by gas chromatography directly would require long analysis times because the boiling point of fatty acids is very high so we need a derivatization before analysis. This study aims to obtain a valid method for subsequent use on set levels of omega-3, omega-6 and omega-9 in the edible oil products. Derivatization performed by Lepage esterification method using the reagent methanol-toluene 4:1 (v/v) and acetyl chloride as catalyst. Analysis was performed using gas chromatography with CBP-10 column (60m x 0.32mm), temperature programmed column 200-230ºC, increase of 2°C/min, and maintained for 20 minutes. The temperature of the injector and detector temperature respectively 230 and 250oC; helium gas flow rate of 1.40 mL/min, the injection volume of 1.0 µL, and detected with a flame ionization detector. Retrieved retention time of 16.445 minutes omega-3, omega-6 15.922 minutes, and omega-9 15.820 minutes. Precision test showed good results with kv omega-3, omega-6 and omega-9, respectively for 1.1022%, 1.22% and 0.547%. Test recoveries respectively for 98.60%, 99.12% and 98.83%. The test results of samples A, B, and C obtained successively omega-9 amounted to 99.82%, 99.29%, 84.05% and shows no signs of omega-3 and omega-6.
"
2015
S64958
UI - Skripsi Membership  Universitas Indonesia Library
<<   1 2 3 4 5 6 7 8 9 10   >>