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Abstrak :
Penelitian ini bertujuan untuk mengevaluasi kombinasi lilin dan karbon sebagai material ekuivalen jaringan yang dapat merepresentasikan jaringan tubuh manusia. Parameter atomik yang umum digunakan untuk merepresentasikan adalah densitas elektron dan nomor atom efektif. Penelitian ini menggunakan metode dual-energy CT (DECT) dengan menggunakan formulasi alpha blending (Möhler, 2017) dan DEEDZ (Saito, 2017). Sampel yang dievaluasi yaitu fantom sampel jaringan lemak (80% parafin, 10% cecek, dan 10% karbon), otot (80% gondorukem, 10% cecek, dan 10% karbon), white matter brain (68% gondorukem, 16% cecek, dan 16% karbon), dan grey matter brain (60% gondorukem, 20% cecek, dan 20% karbon). Berdasarkan hasil uji, fantom sampel lemak, otot, grey matter brain, dan white matter brain memiliki kesalahan relatif densitas elektron sebesar masing-masing 4.6%, 2.6%, 4.4%, dan 4.8%, serta kesalahan relatif nomor atom efektif masing-masing sebesar 11.9%, 19.7%, 19.5%, dan 19.4%. Selain itu, pada penelitian ini dilakukan pula verifikasi fantom sampel hati, air, dan PMMA dengan kombinasi penelitian sebelumnya. Fantom sampel hati, air, dan PMMA memiliki kesalahan relatif densitas elektron sebesar masing-masing 7.0%, 1.5%, dan 0.5%, serta kesalahan relatif nomor atom efektif masing-masing sebesar 16.7%, 22.6%, dan 2.1%. ......This study aims to evaluate the combination of wax and carbon as tissue-equivalent material which can represent human body tissue. The atomic parameters used to represent it are electron density and effective atomic number. This study used dual-energy CT (DECT) method using alpha blending formulation (Möhler, 2017) and DEEDZ formulation (Saito, 2017). The samples evaluated in this study were phantom sample of fat (80% paraffin, 10% cecek, and 10% carbon), muscle (80% gondorukem, 10% cecek, and 10% carbon), white matter brain (68% gondorukem, 16% cecek, and 16% carbon), and gray matter brain (60% gondorukem, 20% cecek, and 20% carbon). Based on the test results, phantom samples of fat, muscle, grey matter brain, and white matter brain have a relative deviation of electron density of 4.6%, 2.6%, 4.4%, and 4.8%, and relative errors of effective atomic number of 11.9%, 19.7%, 19.5%, and 19.4%, respectively. This study also verified phantom samples of liver, water, and PMMA with a combination of previous studies. Phantom samples of liver, water, and PMMA have a relative deviation of electron density of 7.0%, 1.5%, and 0.5%, and relative errors of effective atomic numbers of 16.7%, 22.6%, and 2.1%, respectively.

Abstrak :
Terdepositnya parafin wax dalam minyak mentah dapat menimbulkan gangguan dalam proses produksi minyak mentah, terutama ketika transportasi dalam pipa saluran. Kristal wax ini mengendap di dalam pipa dan akan menghalangi aliran minyak mentah, untuk itu perlu adanya penanganan serius untuk mencarikan solusi atas masalah ini. Salah satu cara penanganan pengendapan wax adalah dengan menambahkan aditif berupa pour point depressant ke dalam minyak mentah. Pada penelitian kali ini, diseleksi 23 jenis pour point depressant (PPD) yang berasal dari berbagai supplier bahan kimia dan diujikan kemampuannya menurunkan pour point dari minyak mentah fraksi berat dari Cilacap. Hasil seleksi didapatkan satu aditif terbaik yaitu dengan kode L, dan dikarakterisasi dengan GCMS dan FTIR didapatkan senyawa campuran alkanol rantai panjang dan naphthalene. Dengan penambahan 5000μL/L, aditif ini mampu menurunkan pour point sampel minyak mentah sebesar 6oC dan dengan penambahan 10000μL/L, mampu menurunkan sebesar 9oC. Untuk mengetahui bagaimana aditif PPD tersebut berinteraksi dengan wax, dilakukan studi dengan mengujinya lewat instrumentasi XRD (X-Ray Diffraction) yang menghasilkan intensitas peak XRD yang menurun seiring penambahan dosis PPD dan instrumentasi CPM (Cross Polarized Microscopy) memperlihatkan bahwa setelah penambahan PPD, wax yang terbentuk saat suhu 30oC lebih sedikit. Kesimpulan didapati bahwa PPD jenis ini mampu teradsorpsi di permukaan wax sehingga menghambat proses kristalisasi wax. ...... The precipitation of paraffinic wax in the crude oil causes a serious problem to the production process of oils, especially in the process of transportation in the pipelines. The deposition of wax in the pipeline trapped out the oil and inhibit the oil to flow. A serious treatment must be applied to solve this problems. One of the method is the addition of additives into the crudes. The additives are named as pour point depressants (PPD). In this research, 1 of the best from 23 pour point depressant additives that come from some chemical suppliers, was selected. The selection is based on their performance to depress the initial pour point of the Cilacap’s heavy crude oil. The PPD with L code was known having the best performance on the crude. This PPD was characterized by FTIR and GCMS, hence obtained the information about this PPD, it is consist of long chain of alkanol and naphthalene. With the dosage of 5000μL/L, this PPD can decrease the pour point as much as 6oC from the initial point, and with the dosage of 10000μL/L, this PPD can decrease as much as 9oC. In order to know how can this type of PPD interact with the wax, studied had been done with XRD (X-Ray Diffraction) and CPM (Cross Polarized Microscopy) instrumentation. The increasing dosage of PPD in wax caused the peak intensity of wax in XRD decrease. CPM instrumentation showed that after the addition of PPD, the wax precipated from crude oil decrease significantly on the temperature of 30oC. In conclusion, this type of PPD can interfere the wax crystal growth by adsorption, the adsorption takes place on the surface of wax crystal.

Abstrak :
Dalam transportasi minyak mentah menggunakan pipa saluran bawah laut, sering terjadi terhambatnya aliran crude oil akibat pengendapan wax. Untuk mencegah terjadinya pengendapan wax dengan menambahkan aditif ke dalam crude oil. Dalam penelitian ini digunakan aditif alkil glukosida (AG) hasil sintesis dan komersial. Konsentrasi aditif divariasikan menjadi 1%, 2%, dan 3% dengan variasi volume (50, 70, 100, 200, 300, 400, 700, 900, 1000, 1500, 2000, dan 2500 µL). Sintesis AG dilakukan variasi penambahan mol alkohol lemak, waktu reaksi, dan katalis. Hasil variasi terbaik didapatkan dengan 0,053 mol alkohol lemak, waktu reaksi 4 jam, dan katalis 2% w/t. Dilakukan uji pour point pada AG sintesis dan AG komersial. Dari hasil penelitian pada AG sintesis dan AG komersial mencapai penurunan pour point optimum sebesar 9°C dan 12°C. Hasil CPM menunjukkan adanya perubahan ukuran kristal dan hasil spektrum FTIR mendukung hasil tersebut dengan menunjukkan adanya interaksi antara aditif dengan wax. Dari studi tersebut diketahui bahwa aditif AG dapat digunakan sebagai inhibitor wax yang mampu menghambat pertumbuhan kristal wax pada model crude oil.

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In the transportation of crude oil using a subsea pipeline, often inhibition of the flow of crude oil due to deposition of wax. To prevent the deposition of wax by adding additives to the crude oil. In this study the use of additives alkyl glucoside (AG) results of synthesis and AG commercial. Additive concentration was varied to 1%, 2%, and 3% by volume variation (50, 70, 100, 200, 300, 400, 700, 900, 1000, 1500, 2000, and 2500 mL). Synthesis AG performed variations addition mole fatty alcohol, reaction time, and catalyst. The best results obtained with a variation of 0.053 mol fatty alcohol, the reaction time of 4 hours, and the catalyst 2% w/t. Pour point test conducted on AG synthesis and AG commercial. From the results of AG synthesis and AG commercial reach optimum reduction in pour point of 9°C and 12°C. CPM results indicate a change in the size of the crystal and the results of spectra FTIR support these results by showing the interaction between additives with wax. From these studies it is known that AG additives can be used as a wax inhibitor capable of inhibiting the growth of wax crystals on the model of crude oil.

Abstrak :
Penelitian ini bertujun menelaah pengaruh konservasi emulsi lilin terhadap daya simpan buah tomat (Lypoersicum esculentum l.). Hasil penelitian menunjukan bahawa pelapisan lilin pada konservasi 7% dapat memperpanjang daya simpan hingga 14 hari setelah panen.

Abstrak :
The effect of carnauba wax consentration to pharmacotechnical characteristics on the granules and tablets that made by hot melt granulation method have been studied.Fomula I? V with composition : 10, 20, 30, 40, and 50% w/w carnauba wax,propranolol hydrochloride 60 mg/tablet, and lactose to the 340 mg was mixed and melted, and than sieved to the mesh 16 siever. The granules were evaluated and lubricated by 1% magnesium stearat and 2% talcum. Then it were compressed into tablet which each weight was 350 mg and the tablets were evaluated. The results showed that hot melt granulatin form granules and tablets that acceptable pharmacotechnical properties.

Abstrak :
Minyak mentah yang memiliki kandungan wax tinggi dapat menyebabkan timbulnya permasalahan selama proses transportasi berlangsung. Jika titik awal pembentukan deposisi dapat diprediksi dengan baik dan laju pengendapan dapat dihitung secara akurat maka strategi penanganannya akan tepat sasaran. Dalam penelitian ini, pembentukan deposisi wax diprediksi dengan menggunakan simulasi OLGA. Uji laboratorium atas sampel dari sumur Bravo dilakukan terlebih dahulu untuk mengetahui komposisi fluida, nilai WAT, jumlah fraksi wax dan viskositas. Karakterisasi dan tuning dilakukan dengan bantuan perangkat lunak PVTsim menggunakan hasil pengujian laboratorium. Hasil karakterisasi ini selanjutnya digunakan sebagai input bagi OLGA untuk memprediksi titik awal deposisi serta menghitung laju pengendapannya. Simulasi dilakukan pada laju alir 80000 bpd pada beberapa periode waktu. Kemudian dilakukan juga beberapa variasi laju alir untuk melihat pengaruhnya terhadap titik awal deposisi wax serta tingkat ketebalannya. Untuk kasus lapangan Charlie-Bravo dengan laju alir 80000 bpd, titik awal deposisi wax terbentuk pada jarak 4 km pada temperatur 31,1 oC. Laju pengendapan akan terus meningkat seiring berjalannya waktu dan akan mencapai ketebalan 1 mm pada jarak 6,87 km setelah 82 hari. Rekomendasi untuk melakukan pigging dikeluarkan apabila ketebalan wax pada dinding pipa mencapai 1 mm agar peningkatan laju pengendapan dapat dikurangi. ...... The presence of wax in crude oil can lead to the formation of wax deposit on the wall of pipelines. If we can predict the starting point for the formation of wax deposition and calculate the rate accurately then the appropriate mitigation can be well developed. In this study, the wax deposition was predicted using OLGA simulation. Laboratory test from Bravo wells to determine the fluid composition, WAT, amount of wax fraction and viscosity shall be done first. This laboratory test result was then characterized and tuned using the PVTsim. The result was used as an input for OLGA to calculate the rate of wax deposition in pipelines. Simulation was conducted at a flow rate of 80000 bpd with the time of 1-60 days. The same thing was also done at several flow rates to see the effect of wax formation and its level of thickness. In the case of Charlie-Bravo field that produce 80000 bpd of liquid, wax began to precipitate at a distance of 4 km and temperature 31.1 oC. The deposition rate will continue to increase over the time and will get a thickness of 1 mm at the distance of 6.87 km after flowing for about 82 days Pigging is recommended if the wax thickness in the pipe achieves 1 mm. This is as a preventive maintenance to reduce an escalation of rate deposition.

Abstrak :
[Penelitian mengenai karakterisasi morofologi bunga dan pollinaria 14 spesies Hoya atau bunga lilin telah dilakukan dari Februari--Mei 2015. Penelitian bertujuan untuk mendeskripsikan dan membandingkan 14 spesies Hoya koleksi Kebun Raya Bogor (KRB) berdasarkan morfologi bunga dan pollinaria. Sampel yang digunakan merupakan 14 spesimen awetan basah bunga koleksi KRB. Data yang diambil berupa data kualitatif, kuantitatif, dan visual melalui metode pengamatan langsung. Hasil penelitian menunjukkan variasi bentuk dan ukuran bunga serta pollinaria pada 14 spesies Hoya koleksi KRB. Hasil juga menunjukkan adanya karakter pembeda antarspesies yaitu bentuk calyx, keberadaan trikom pada bagian tepi calyx, bentuk corolla, bentuk corona, pelengkap anther, bentuk pollinia, bentuk corpusculum, ada atau tidaknya caudicle, bentuk caudicle, ada atau tidaknya pellucid edge, dan bentuk translator. ;Research on morphological flowers and pollinaria characterization from 14 species Hoya or wax flowers was conducted from Februari--Mei 2015. The aims of this research was to describe and compare 14 species of Hoya collections from Bogor Botanical Garden (BBG) based on flower and pollinaria morphology. The research was carried out using preserved 14 specimen collections from BBG. The qualitative, quantitative, and visual data were collected by direct observation method. The result showed that the shape and size characters from flowers and pollinaria of 14 Hoya species from BBG were varied. Beside variation of Hoya flowers and pollinaria, there were also some distinguish characters of calyx shape, presence or absence of trichome in calyx, corolla shape, corona shape, anther appendages, pollinia shape, corpusculum shape, presence or absence of caudicle, caudicle shape, presence or absence of pellucid edge , and translator shape. ;Research on morphological flowers and pollinaria characterization from 14 species Hoya or wax flowers was conducted from Februari--Mei 2015. The aims of this research was to describe and compare 14 species of Hoya collections from Bogor Botanical Garden (BBG) based on flower and pollinaria morphology. The research was carried out using preserved 14 specimen collections from BBG. The qualitative, quantitative, and visual data were collected by direct observation method. The result showed that the shape and size characters from flowers and pollinaria of 14 Hoya species from BBG were varied. Beside variation of Hoya flowers and pollinaria, there were also some distinguish characters of calyx shape, presence or absence of trichome in calyx, corolla shape, corona shape, anther appendages, pollinia shape, corpusculum shape, presence or absence of caudicle, caudicle shape, presence or absence of pellucid edge , and translator shape. , Research on morphological flowers and pollinaria characterization from 14 species Hoya or wax flowers was conducted from Februari--Mei 2015. The aims of this research was to describe and compare 14 species of Hoya collections from Bogor Botanical Garden (BBG) based on flower and pollinaria morphology. The research was carried out using preserved 14 specimen collections from BBG. The qualitative, quantitative, and visual data were collected by direct observation method. The result showed that the shape and size characters from flowers and pollinaria of 14 Hoya species from BBG were varied. Beside variation of Hoya flowers and pollinaria, there were also some distinguish characters of calyx shape, presence or absence of trichome in calyx, corolla shape, corona shape, anther appendages, pollinia shape, corpusculum shape, presence or absence of caudicle, caudicle shape, presence or absence of pellucid edge , and translator shape. ]

Abstrak :
Bioavtur merupakan alternatif bahan bakar transportasi udara. Indonesia memiliki minyak kelapa sawit terbesar, hasil olahannya dikonversi menjadi senyawa parafin yang merupakan salah satu bahan baku bioavtur. Penelitian ini, NiMoO4/SBA-15 sebagai bahan katalis bimetalik disintesis untuk konversi asam palmitat menjadi parafin melalui reaksi deoksigenasi. SBA-15 disintesis dengan metode sol gel dan variasi NiMoO4/SBA disintesis melalui metode impregnasi basah secara spray beserta katalis monometalik NiO/SBA-15 dan MoO3/SBA-15 dikarakterisasi dengan XRD, FTIR, SAXS, XRF, SEM-EDX Mapping, dan BET. Analisis XRD dan XRF menunjukkan keberhasilan impregnasi NiO, MoO3, dan NiMoO pada SBA-15. Difraktogram sinar-X dan Scanning Electron Microscope (SEM) mengkonfirmasi proses imregnasi basah secara spray dari partikel logam tidak mengubah struktur heksagonal penyangga katalis. Katalis NiMoO4/SBA-15 diuji dalam reaksi deoksigenasi asam palmitat variasri komposisi Ni:Mo, yaitu: 10:0, 2,5:7,5, 5:5, dan 7,5:2,5 waktu 150 menit. Ditinjau dari hasil GC-MS variasi NiMoO4/SBA-15 5:5 memiliki kondisi paling optimum. NiMoO4/SBA-15 5:5 dilakukan pengujian kembali dengan variasi waktu 90 dan 120 menit menunjukan bahwa waktu 120 menit merupakan waktu paling optimum dengan hasil persen yield 86,164 dan persen konversi 61,348. Uji reusabilitas NiMoO4/SBA-15 (5:5) dilakukan dengan menggunakan katalis sebanyak dua siklus. Analisis dengan FT-IR menunjukan bahwa intensitas pada puncak SBA-15 dan NiMoO4 mengalami penurunan intensitas, namun tidak menghasilkan puncak baru. ......Bioavtur is an alternative fuel for air transportation. Indonesia has the largest palm oil, the processed product is converted into paraffin compounds which are one of the raw materials for bioavtur. In this study, NiMoO4/SBA-15 as a bimetallic catalyst was synthesized for the conversion of palmitic acid to paraffin through a deoxygenation reaction. SBA-15 was synthesized by sol gel method and variations of NiMoO4/SBA were synthesized by wet spray impregnation method with monometallic catalysts NiO/SBA-15 and MoO3/SBA-15 characterized by XRD, FTIR, SAXS, XRF, SEM-EDX Mapping, and BET. XRD and XRF analysis showed the successful impregnation of NiO, MoO3, and NiMoO4 on SBA-15. X-ray diffractogram and Scanning Electron Microscope (SEM) confirmed that the wet spray imregnation process of metal particles did not change the hexagonal structure of the catalyst support. The NiMoO4/SBA-15 catalyst was tested in a palmitic acid deoxygenation reaction with various Ni:Mo compositions, namely: 10:0, 2.5:7.5, 5:5 and 7.5:2.5 for 150 minutes. Judging from the GC-MS results, the NiMoO4/SBA-15 5:5 variation has the most optimum conditions. NiMoO4/SBA-15 5:5 was tested again with variations of 90 and 120 minutes showing that 120 minutes was the most optimal time with a yield percent yield of 86.164 and a conversion percentage of 61.348. NiMoO4/SBA-15 (5:5) reusability test was carried out using two cycles of catalyst. Analysis with FT-IR showed that the intensity of the SBA-15 and NiMoO4 peaks decreased in intensity, but did not produce new peaks.

Abstrak :
Pada sistem transportasi minyak mentah melalui sistem perpipaan sering dijumpai permasalahan yang dapat mengganggu pendistribusian minyak mentah. Oleh karena itu, prediksi yang tepat dari karakteristik pengendapan lilin diperlukan untuk mengontrol pengendapan lilin di dalam pipa. Penelitian ini bertujuan untuk memprediksi karakteristik pengendapan lilin dengan menganalisis pengaruh variasi tekanan dan temperatur minyak mentah. Tekanan divariasikan pada 1,5 bar, 2,5 bar, 5 bar, 8 bar, dan 12 bar untuk mengevaluasi pengaruhnya terhadap ketebalan dan laju pengendapan lilin. Selanjutnya dilakukan variasi suhu dengan variasi 35°C, 40°C, 45°C, 50°C, 55°C, dan 60°C. Simulasi dilakukan dengan menggunakan software aliran multi fasa OLGA untuk mendapatkan profil ketebalan endapan (mm). Sedangkan analisis ekonomi mengacu pada studi kelayakan. Beberapa skenario dibandingkan untuk menentukan intervensi terbaik yang akan diterapkan. Hasil penelitian menunjukkan bahwa jumlah wax yang terdeposit menurun seiring dengan meningkatnya tekanan, sedangkan temperatur yang lebih tinggi menghasilkan gradien temperatur yang lebih besar. Analisis kelayakan ekonomi hanya dilakukan pada skenario satu dan dua yang membutuhkan penggunaan pompa. Skenario satu, yang mencakup pompa tambahan, memiliki NPV 199.882 dan IRR 30%. Skenario dua, mengganti pompa eksisting dengan pompa berkapasitas lebih tinggi, memiliki NPV 328.192 dan IRR 40%. Akibatnya, skenario dua disarankan untuk mengurangi jumlah deposit lilin ......In the crude oil transportation system through the pipeline system, problems caused by wax are often encountered that can disrupt the distribution of crude oil, thus flow assurance is not achieved. Therefore, the correct prediction of wax deposition characteristics is needed to control the deposition of wax in the pipe. This study aims to predict the characteristics of wax deposition by analysing the effect of pressure and temperature variations of crude oil. Pressure was varied at 1.5 bar, 2.5 bar, 5 bar, 8 bar, and 12 bar to evaluate the effect on the thickness and deposition rate of wax. Furthermore, temperature variations were carried out with variations of 35°C, 40°C, 45°C, 50°C, 55°C, and 60°C. The simulations were carried out using multi-phase flow software OLGA to obtain a deposit thickness profile (mm). Meanwhile, the economical-analysis refers to feasibility study. Several scenarios are compared to determine the best intervention to be applied. The results shows that the amount of wax deposited decreases as the pressure increases, while higher temperature resulting in a greater the temperature gradient. The economic feasibility analysis is only carried out in scenario one and two, which require the usage of pumps. Scenario one, which includes an extra pump, has an NPV of 199,882 and an IRR of 30%. Scenario two, replacing the existing pump with a higher-capacity pump, has an NPV of 328,192 and an IRR of 40%. As a result, scenario two is advised to reduce the amount of wax deposited.