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"Metal Matrix Composite (MMCs) is combination from two material or more with metal as matrix developed to improve the nature of metal; strength, hardness. electric resistance stability at high temperature. Aluminum as a matrix composite developed because is light, cheap, and easy to fabrication. Pressureless infiltration is one of the fabrication process of metal matrix composite in a melt condition which is developing because more economic; no need complicated equipments. Characteristic of metal matrix: composite can be influenced by infiltration temperature, dopant content (Magnesium), % Vf reinforcement and holding time. This research aim is to study the effect of temperature infiltration, as well as magnesium content on characterization of A£fA1,O, metal matrix composite i.e, thermal expansion, hardness, wear resistance, porosity and density as well as metallography. The infiltration temperature used various from 800 to 1200°C and Al;03 particle reinforcement was 5U%Fj= The magnesium content was also various from 4% to l2% wt and holding time was I0 hours. The results shows that higher magnesium content produced more Al molten infiltrated into ,41,O,~ preform. It is found that the optimum performance of composite produced at 1100° C."

"Persediaan minyak bumi sebagai salah satu sumber bahan bakar tak terbarukan semakin menipis. Solusi untuk masalah cadangan minyak bumi yang menipis adalah pencarian sumber energi terbarukan, salah satu di antaranya adalah renewable diesel. Penelitian ini melakukan studi penggunaan model prediktif Analytical Semi Empirical Model(ASEM) dalam menggambarkan produksi renewable dieseldari hidrodeoksigenasi minyak nabati.Penelitian ini bertujuan menentukan kondisi suhu optimum dalam aspek ekonomis dan kualitas melalui simulasi model ASEM. Data penelitiandisimulasikan dengan perangkat lunak komputasi numerik menggunakan metode curve fitting.Hasil dari simulasi untuk suhu optimum memproduksi produk renewable dieselberkisar antara 292,5 °C - 337,6 °C. Dengan akurasi nilai R2 yang mendekati 1, berkisar antara 0,913 - 0,999 dan SSE yang mendekati 0, berkisar antara 3,078 - 10^-15, bergantung padajenis yang diinginkan.

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Petroleum oil reserve asone of the largest source of unrenewable fuel is decreasing in quantity. The solution is the search for a renewable energy source, sch as renewable diesel. This researchstudiesthe implementationof the predictive Analytical Semi Empirical Model (ASEM)in representing renewable diesel productkrom hydrodeoxygenation of vegetable oil.

This research aims for optimum temperature condition of each products through simulationofproducing renewable diesel in higher economical and quality aspect by using ASEM model simulation. Experimental secondary are simulated using Numerical Computation Software with curve fitting method.

The simulation result ofoptimum temperature condition to produce renewable dieselis 292,5 oC.With accuracy R2value is 0,913–0,999and SSE value is 3,078–10-15, depend on desirable product."

"Levoglucosan adalah sebuah komponen utama yang berbentuk cairan kental dari hasil pirolisis biomassa yang banyak dimanfaatkan sebagai pestisida buatan, growth regulators, macrolide antibiotics dan lain-lain. Biomassa tersusun atas hemisellulosa, sellulosa, lignin dan sejumlah kecil komponen organik yang masing-masing dapat terpirolisis dan terdegradasi dengan laju yang berbeda, mekanisme dan jalur yang berbeda. Diketahui bahwa, levoglucosan adalah produk yang paling banyak diperoleh dalam pirolisis selulosa dari biomassa. Biomassa yang digunakan dalam penelitian ini adalah cangkang kelapa sawit dan tandan kosong kelapa sawit. Pemilihan biomassa tersebut didasarkan dari komposisi biomassa tersebut yang mengandung > 30 % selulosa. Faktor kondisi operasi pirolisis yaitu holding time dan suhu optimum, telah diteliti sebelumnya dapat mempengaruhi yield levoglucosan. Pada penelitian ini, metode pirolisis yang dipilih adalah fast pyrolysis. Pemilihan ini dikarenakan levoglucosan akan terbentuk dari depolimerasi selulosa pada tahap awal fast-pyrolysis pada rentang  suhu 315°C-400°C dan setelah itu akan terjadi secondary reaction menghasilkan turunan levoglucosan yaitu furan dan piranosa terdehidrasi. Dalam penelitian ini, fast pyrolysis dilakukan dalam reaktor unggun tetap dengan konfigurasi looping system pada rentang suhu (450 - 550)°C, laju alir N2 adalah 1500 ml/menit dan 3000 ml/menit serta variasi biomassa adalah 51.3 gram dan 81.3 gram. Analisis levoglucosan didukung dengan instrumen GC-MS. Hasil levoglucosan pada biomassa tandan kosong sawit tidak diperoleh karena proses pirolisis tidak terjadi sampai lapisan selulosa biomassa sedangkan pada biomassa cangkang sawit diperoleh yield levoglucosan tertinggi pada suhu 500°C dengan holding time 2.4 s yaitu sebesar 2.33 % (g/g) biomassa.

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Levoglucosan is a major component in the form of thick liquid from the results of biomass pyrolysis which is widely used as artificial pesticides, growth regulators, macrolide antibiotics and others. Biomass is composed of hemicellulose, cellulose, lignin and a small amount of organic components which each can be hydrolyzed and degraded at different rates, different mechanisms and pathways.

It is known that levoglucosan is the product most obtained from cellulose pyrolysis of biomass. The biomass used in this study is  palm kernel shell and empty palm fruit bunches. The choice of biomass is based on the composition of the biomass containing > 30% cellulose. The factors of pyrolysis operating namely holding time and optimum temperature conditions that have been studied previously, can affect levoglucosan yield.

In this study, the pyrolysis method chosen was fast pyrolysis. This selection is because levoglucosan will be formed from cellulose depolymerization in the early stages of fast-pyrolysis at a temperature range of 315°C-400°C and after that a secondary reaction will occur resulting in levoglucosan derivatives namely furan and dehydrated pyranose.

In this study, fast pyrolysis was carried out in a fixed bed reactor with a looping system configuration in the temperature range (450-550)°C, the flow rate of N2 was 1500 ml/minute and 3000 ml/minute and the biomass variation was 51.3 grams and 81.3 grams. Analysis of levoglucosan was supported by the GC-MS instrument.

The results of levoglucosan in the empty palm fruit bunches biomass were not obtained because the pyrolysis process did not occur until the cellulose layer of biomass while in palm kernel shell biomass was obtained the highest levoglucosan content at 500°C with a holding time of 2.4 s which was 2.33 % (g/g) biomass."