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Abstrak :
Tujuan dari penelitian ini adalah mengetahui pengaruh suhu vulkanisasi terhadap sifat mekanis dan kinetika vulkanisasi komposit NBR. Formulasi komposit menggunakan dua macam carbon black yaitu N-330 dan N-774. Kinetika vulkanisasi ditentukan dengan alat Moving Die Rheometer, dimana proses vulkanisasi berlangsung dikaitkan dengan torsi dan waktu. Proses pembuatan vulkanisat menggunakan hydraulic press pada suhu 150ºC dan 160ºC. Sifat mekanis komposit NBR yang diamati adalah tegangan putus, perpanjangan putus, kekerasan dan kuat sobek. Kinetika vulkanisasi didekati dengan persamaan Arrhenius dikaitkan dengan mekanisme reaksi dan diasumsikan orde satu. Hasil penelitian menunjukkan bahwa kinetika vulkanisasi dapat didekati dengan persamaan dari data reometer. Surface area carbon black sangat kuat mempengaruhi sifat mekanis dan rate constant (k) dari komposit NBR. Carbon black N 330 merupakan bahan pengisi yang bersifat sebagai penguat dan memberikan sifat mekanis tertinggi dibandingkan carbon black jenis lainnya. ......The aim of this research was to study the effect of vulcanization temperature on mechanical properties and curing kinetics of NBR composites. The composites were formulated by using two types of carbon black i.e. N-330 and N-774. The curing kinetics was determined using Moving Die Rheometer. The network formation processes were related to torque and time. The vulcanizates were obtained by compression molding in a hydraulic press at 150°C and 160°C. The mechanical properties observed include tensile strength, elongation at break, hardness, and tear strength. Kinetics studies were approached by Arrhenius equation and the reaction mechanism was assumed following first order reaction. The results showed that curing kinetics can be approached by the equation from the rheometer data. The surface area of carbon black strongly influenced the mechanical properties and rate constant (k) of NBR composite. Carbon black N-330 can be used as a desirable reinforcing filler which gave a higher mechanical properties than the other type of carbon black

Abstrak :
ABSTRAK
Kebakaran hutan dan lahan telah menjadi ancaman cukup serius bagi masyarakat secara global pada dua dekade terakhir karena kontribusinya terhadap rusaknya ekosistem, peningkatan emisi karbon, penurunan keanekaragaman hayati, gangguan kesehatan, dan kerugian ekonomi. Kalimantan merupakan daerah yang rawan terhadap bencana kebakaran hutan dan lahan. Penelitian ini bertujuan untuk mengetahui model identifikasi burned area yang paling sesuai diaplikasikan di Kalimantan dengan menggunakan citra MODIS serta mengkaji sebaran burned area secara spasial (spatial distribution). Identifikasi burned area dilakukan dengan menggunakan indeks vegetasi (NDVI), indeks kebakaran (NBR), dan nilai reflektansi dari citra MODIS. Analisis sebaran secara spasial dilakukan dengan menumpangsusunkan (overlay) antara burned area dengan variabelvariabel penutup lahan, curah hujan, elevasi, kemiringan lereng, jenis tanah, dan jarak dengan permukiman. Hasil penelitian ini menunjukkan bahwa dari semua model, model NBR memberikan tingkat akurasi paling tinggi, yaitu sebesar 0,635 atau 63,5%. Luas total burned area di Kalimantan pada tahun 2011 sekitar 343.290 ha. Sebaran spasial burned area di Kalimantan sebagian besar berada pada suatu wilayah yang mempunyai karakteristik; (a) curah hujan bulanan kurang dari 200 mm/bulan, (b) jenis tanah Tropohemists, Tropaquepts, atau Quartzipsaments, (c) penutup lahan semak/belukar, sawah, hutan, atau ladang/tegalan, (d) elevasi di bawah 100 meter dpl, (e) datar dengan kemiringan 0 ? 3%, dan (f) relatif dekat dengan permukiman.

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Abstract
Forest and land fire has been a serious threat for global communities since two last decades because their contribution to ecosystem damages, carbon emission increasing, biodiversity decreasing, healthy interfering, and also economic lost. Kalimantan is the prone area of the forest and land fire. Objectives of the research are to find out the appropriate identification model of burned area derived from MODIS imagery and to analyze their spatial distribution. The burned area identification was developed by using the variabels extracted from MODIS imagery such vegetation index (NDVI), burn index (NBR), and reflectance values. Then, the spatial distribution was analyzed by using overlay methods between burned area and variabels of rainfall, landcover, elevation, slope, soil type and the distances from settlements. The research concludes that among several models, the NBR model show the highest accuracy, that is 63,5 %. Total of the burned area in Kalimantan for 2011 was about 343,290 hectares. The burned area spatial distribution in Kalimantan mostly located on the regions which have characteristics; (a) rainfall less than 200 mm/month, (b) soil type of Tropohemists, Tropaquepts, or Quartzipsaments, (c) landcover of shrublands, paddy fields, forests, or croplands, (d) elevation less than 100 metres asl, (e) flat regions with slope about 0 ? 3%, and (f) relatively near from settlements.

Abstrak :
Recently, much attention has been focused on research to replace petroleum-based plasticizers, with biodegradable materials, such as biopolymer which offers competitive mechanical properties. In this study, castor oil was modified with maleic anhydride (MAH) to produce bioplasticizer named maleated anhydride castor oil (MACO), and used in nitrile butadiene rubber (NBR)/poly vinyl chloride (PVC) blend. The effect of MACO on its cure characteristics and mechanical properties of NBR/PVC blend has been determined. The reactions were carried out at different castor oil (CO)/xylene ratios, i.e. 1:0 and 1:1 by weight, and fixed CO/MAH ratio, 1:3 by mole. DOP, CO, and MACO were added into each NBR/PVC blend according to the formula. It was found that the viscosity and safe process level of NBR/PVC blend is similar from all plasticizer, however, MACO (1:0) showed the highest cure rate index (CRI). MACO-based plasticizer gave a higher value of the mechanical properties of the NBR/PVC blend as compared to DOP based plasticizer. MACO (1:1) based plasticizer showed a rather significance performance compared to another type of plasticizers both before and after aging. The value of hardness, elongation at break, tensile strength, and tear strength were 96 Shore A, 155.91 %, 19.15 MPa, and 74.47 MPa, respectively. From this result, NBR/PVC blends based on MACO plasticizer can potentially replace the DOP, and therefore, making the rubber blends eco-friendly.