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"Pelumas nabati yang berbasis minyak sawit memiliki komposisi trigliserida yang merupakan gabungan dari gugus esters ( polyhydroxy alcohol glycerol ) dengan asam karboksilat (asam lemak) jenuh dan tidak jenuh. Kandungan asam lemak oleic monounsaturated yang sangat tinggi akan meningkatkan sifat pelumas. Sintesis minyak sawit trigliserida dengan alkohol dilakukan dengan menggunakan zeolit alam malang yang di-loading larutan basa KOH sebagai katalis heterogen diharapkan dapat melalui tahapan reaksi trans-esterifikasi sebagai tahapan awal reaksi sintesis pelumas nabati. Katalis heterogen cenderung lebih banyak digunakan pada industri-industri karena pada proses pemisahannya lebih mudah dilakukan dan juga zeolit sebagai support dapat berfungsi sebagai adsorben untuk pemurnian. Secara komersial proses dengan menggunakan katalis basa lebih sering digunakan karena aktivitas katalis dari basa lebih tinggi dari asam dan katalis asam lebih korosif. Hasil sintesis ester base-oil terbaik didapatkan dengan zeolit yang dengan 10 % (%wt) KOH, dengan waktu reaksi 5 jam dan perbandingan molar ratio dari metanol dan minyak nabati adalah 6:1. Terjadi perubahan sifat fisis dari trigliserida menjadi ester seperti turunnya densitas dari 0,91 ke 0,8668 dan viskositas dari 43,4656 ke 7,3060. Konversi trigliserida menjadi metil ester dengan analisa GCMS adalah 87,81%.

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Bio-base-oil based on palm oil has composition triglyceride that be federation of cluster ester (polyhydroxy alcohol glycerol) with saturated and unsaturated carboksilate acid (fatty acid). The high ingredient of monosaturated oleic fatty acid will increase lubricant character. Synthesis palm oil triglycride with alcohol using natural zeolite malang is loaded by alkali solution KOH as a heterogenous catalayst supposed can pass stage reaction transesterification as the first of the reaction stage synthesis bio-base-oil. Heterogenous catalyst inclined more used in industrial because the separation process is easier and also zeolite as a support can functioned as adsorben for purifier. Commercially, process using base as a catalyst is more often because the catalyst activity from base catalyzed is higher than acid and acid catalyst is more corrosive. The highest result from producing ester base-oil obtained with zeolite loaded by 10% (%wt) KOH, ,reaction time 5 hour, and then ratio molar from methanol and palm oil is 6:1. The alteration is occur on physical behavior from tricglyceride to ester with decreased of density from 0,91 to 0,8668 and viscosity from 43,4656 to 7,3060. Conversion triglyceride become ester is 87,81%."

"Senyawa stilben terprenilasi diketahui memiliki banyak potensi aktivitas biologis seperti anti-tumor dan anti-kanker. Pada umumnya senyawa-senyawa tersebut didapat dari hasil isolasi atau ekstraksi. Oleh sebab itu diperlukan metode untuk dapat mensintesis stilben terprenilasi dengan menggunakan katalis yang mempunyai aktivitas dan selektivitas yang baik. Reaksi prenilasi senyawa stilben dapat dikatalisis dengan menggunakan katalis zeolit KNaX dan γ-Al2O3/NaOH/Na pada suhu 600C dengan waktu yang divariasikan. Waktu optimum untuk reaksi prenilasi trans-stilben dengan katalis zeolit KNaX adalah 12 jam dengan persen konversi produk sebesar 17,65 %. Waktu optimum untuk reaksi prenilasi trans-stilben dengan katalis γ-Al2O3/NaOH/Na adalah 6 jam dengan persen konversi produk sebesar 18,33 %. Dari hasil tersebut dapat disimpulkan bahwa katalis γ- Al2O3/NaOH/Na memiliki selektivitas dan aktivitas yang lebih baik dibandingkan katalis zeolit KNaX.

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Prenylated stilbene compounds have been known to have many potential biological activities such as anti-tumor and anti-cancer. In general, the compounds were obtained from the isolation or extraction of natural products. Therefore, some methods are needed to synthesize prenylated stilbene, such as using catalyst which has good activity and selectivity. In this research, the prenylation of stilbene was conducted using zeolite KNaX and γ-Al2O3/NaOH/Na as basic catalyst at temperature of 600C with the variation of reaction times. The optimum time for the prenylation reaction of stilbene using zeolite KNaX was 12 hours with the conversion 17.65%. The optimum time for the prenylation reaction of stilbene using γ-Al2O3/NaOH/Na was 6 hours with the conversion 18.33%. According to those results, the catalyst γ-Al2O3/NaOH/Na had better selectivity and activity than KNaX zeolite catalysts."

"Distribusi merupakan pendorong utama profitabilitas keseluruhan sebuah perusahaan. Tingginya biaya distribusi produk di UMKM makanan disebabkan karena tidak adanya perhitungan biaya untuk mendapatkan keputusan distribusi yang optimal. Tujuan dari penelitian ini adalah untuk menghasilkan model distribusi produk di UMKM makanan dengan biaya terendah dan waktu tercepat. Untuk menyelesaikan permasalahan distribusi produk makanan di 5 UMKM makanan, dimodelkan masalah Heterogenous Fleet Vehicle Routing Problem with Time Window (HVRPTW) dalam bentuk Mixed Integer Linear Programming dan diselesaikan menggunakan algoritma branch-and-bound pada perangkat lunak Lingo. Hasil dari penelitian ini adalah optimasi biaya distribusi produk untuk 5 UMKM makanan yang menghasilkan keputusan distribusi dengan biaya terendah dan waktu tercepat. Telah dikembangkan alat untuk perhitungan biaya distribusi yang dapat digunakan oleh UMKM makanan untuk pendukung keputusan distribusi produk harian

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Distribution is the main driver of the overall profitability of a company. The high cost of product distribution in food SMEs is caused by the absence of distribution cost calculation for SMEs to make optimal distribution decisions. The purpose of this research is to provide SMEs with a product distribution model with the lowest cost and fastest time. A Heterogenous Fleet Vehicle Routing Problem (HVRP) for the food distribution problem in 5 food SMEs is modeled in the form of Mixed Integer Linear Programming and solved using branch-and-bound algorithm in Lingo software. The result of this study is the optimization of the distribution cost for 5 food SMEs distribution decisions. A tool for the calcuation of distribution cost is developed for food SMEs to support daily product distribution decisions."

"Sintesis biodiesel dari minyak sawit trigliserida dengan metanol melalui proses transesterifikasi dilakukan dengan menggunakan zeolit alam Malang yang diimpregnasi dengan larutan basa KOH membentuk katalis heterogen. Proses transesterifikasi dilakukan dengan variasi terhadap konsentrasi katalis sebesar 5% dan 10% dengan rasio mol 6:1 dan 10:1. Temperatur reaksi pada 65_C dengan waktu reaksi selama 8 jam pada tiap variasi. Penurunan nilai densitas KOH/z 10% 10:1 (0,8812g) and viskositas KOH/z 5% 10:1 (0,8812cSt), lebih rendah dibanding yang lain, sebelum dan sesudah reaksi menunjukkan bahwa terdapat bagian dari molekul trigliserida yang terputus menjadi molekul yang lebih kecil.Dari hasil penelitian diperoleh bahwa konversi KOH/z 10% 10:1 lebih besar dibanding yang lain (86,4%). Analisa dengan menggunakan spektrum FT-IR minyak sawit sebelum dan sesudah reaksi menunjukkan bahwa peak absorbansi dari gugus metil tinggi. Hal ini berarti terjadi peningkatan jumlah gugus metil selama proses reaksi. Dari analisa dengan menggunakan GC-MS, kandungan senyawa hidrokarbon yang terdapat pada produk biodiesel diketahui sebagian besar mengandung C18.

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Synthesize biodiesel from palm oil triglyceride in methanol through transesterification was used natural zeolite Malang were impregnated using potassium hydroxide as heterogenous catalyst. The transesterification process were varied by catalyst concentration 5% and 10 % with ratio mol 6:1 and 10:1. The reaction temperature was 65_C with reaction time was 8 hours for each variation. The decreasing density KOH/z 10% 10:1 (0,8812g) and viscosity KOH/z 5% 10:1 (0,8812cSt), was lower than the other, of palm oil before and after reaction began have proven that a part of triglyceride molecules in the palm oil were cracked to become smaller molecules.

The results showed that the conversion of KOH/z 10% 10:1 was bigger than the other (86,4%). Further analyst using FT-IR spectra of palm oil before and after reaction had shown that peak of absorbance of methyl group was high. It means that amount of methyl group was increased during the reaction. From the result of GC-MS analyst, the hydrocarbon contents of the biodiesel were known consisting mostly C18."

"Road transport system that has not been effective, resulting in some people prefer a type of mode for transport was motorcycle is wieved as having advantages in terms of mobility, accesibilitas and economally, so that the proportion of motorcycles on the road now reaches 65%. Changes in road transportation system due to the high number of users of motorcycles and behavior has. If not treated, transportation system of roads and accidents will be worse. In this paper, we want to give the effect of the number of motorcycles on the road to the road to the speed of vehicles that can be developed by the driver, and also model the relationship as one of alternative answers in determining the proportion of motorcycles on the streets. Relationship variables that are intended, obtained from traffic counting amount of each type of and it speed in each range of time--per-five-minutes, the data is grouped in intervals poroporsi number of motorcycles that is, conditions 1:10% up to 35%, condition 2:35% s/d 75% and 3 conditions: a merger. regresion analysis methods showed there was a positive and significant correlation coefficients with the indicator for the condition 1 of 0.67, the condition 2 of 0.59 and 0.66 for condition 3. It means that the number of motorcycle affect traffic flow velocity. "

"Dalam waktu yang lama, awalnya dilaporkan bahwa emas secara katalitik dianggap tidak aktif. Namun pada tahun 1980-an nanokatalis heterogen berbasis emas telah banyak dieksplorasi sebagai katalis karena aktivitas yang baik dan selektivitas tinggi yang sangat bergantung pada bentuk dan ukurannya. Pada umumnya, nanokatalis emas dibuat dalam suatu larutan, dalam penelitian ini kami mendemonstrasikan nanokatalis emas yang ditumbuhkan langsung pada substrat kaca yang dilapisi ITO melalui metode seed-mediated growth. Bentuk dan ukuran nanokatalis emas dimanipulasi oleh komposisi surfaktan b-cyclodextrin dan DTAB.Hasil karakterisasi FESEM menunjukkan bahwa penggunaan DTAB yang banyak menghasilkan nanopartikel Au berbentuk bulat dan saling bertumpuk tidak teratur, sedangkan dengan menggunakan b-cyclodextrin yang lebih banyak menghasilkan bentuk cauliflowers yang homogen dengan diameter rata-rata 270 nm. Semua sampel bersifat polikristalin face center cubic dengan bidang kristal 111 yang memiliki puncak intensitas tertinggi. Morfologi ini bersesuaian dengan spektrum serapan optiknya yang memiliki puncak Localized Surface Plasmon Resonance.Hasil uji sifat katalitik nanopartikel Au untuk proses hidrogenasi aseton menunjukkan bahwa laju degradasi aseton oleh katalis A, B dan C secara berturut-turut adalah 43 , 46 dan 58 jauh lebih tinggi daripada larutan aseton tanpa katalis yang hanya terdegradasi 25 . Hal ini mungkin disebabkan karena morfologi cauliflowers memberikan area permukaan aktif yang tinggi dan homogen sebagai tempat terjadinya interaksi/ adsorpsi dengan hidrogen dan aseton.

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For a long time, in the earlier report gold was considered to be catalytically inactive. However, since the 1980s the gold based heterogeneous nanocatalyst have been widely explored as potential catalysts because of their good activity and high selectivity that highly depend on their shape and size. Generally, gold nanocatalyst were prepared in a solution, in this study we demonstrate the gold nanocatalysts were grown directly on ITO coated glass substrates via a seed mediated growth method. The shape and size of gold nanocatalysts were manipulated through the composition of surfactants of b cyclodextrin and DTAB.The characterization results of FESEM showed that a large amount of DTAB in the sample produce a spherical and irregularly stacked shape of Au nanoparticles, whereas the sample using a higher amount b cyclodextrin result in homogenous cauliflowers shape with an average diameter of 270 nm. All samples characteristic are poly crystalline face center cubic with the 111 plane has the highest intensity peak. This morphology corresponds to the optical properties that emerge as the Localized Surface Plasmon Resonance absorbtion peak.The results of catalytic properties in Au nanoparticles for the acetone hydrogenation process showed that the rate of acetone degradation by catalysts was 43 , 46 and 58 , much higher than without catalyst which is only 25 . This may be due to the morphology of cauliflowers provides a high active and homogenous surface area as an interaction adsorption sites with hydrogen and acetone."

"This paper explains the development of a parallel computing platform using the available LAN at the Inter University Center for Computer Science of Indonesia. A software toll like parallel virtual machine enables the networked stations to be harnessed as a huge computing resource, combining various type of computing nodes to run parallel computing tasks. The research was aimed at first: to develop a number of parralel high complexity algorithms such as modelling air pollution distribution based on Gaussian Air Pollution Dispersion Formula which simulates dispersion of pollutant emiotted from industrial exhaust and also from vehicle exhaust ont the road. Secondly these algorithms were used to test the platform to obtain networkd behaviour in supporting the implementation of parallel algorithms. From the experiments conducted there are strong indications that the network based computing facility could be used as a suitable platform for running parallel programs with some restrictions. Optimum performance with near linear speed up could be obtained by carefully partitioning the problems, limiting message passing activities and balancing the load of the participating processors."