Eco-friendly composite made of Timoho Fiber (TF) continuously developed to get the best performance to replace plastic-based synthetic fibers. This study focuses on investigating physical characteristics, mechanical properties, thermal analysis, and the morphology of TF-reinforced polyester composites by adding organic (egg shell powder-ESP) and inorganic (aluminum powder-AP) fillers. Hot press method was used in the composite fabrication with considered volume fraction of TF, organic, and inorganic fillers. The results showed that the density of TF-polyester composites decreases with the increasing volume fraction of the fibers. For additional fillers, it was shown that AP was more effective to be used to improve density than ESP. The tensile and impact strength of the composite increased with increasing TF volume. However, the addition of ESP and AP fillers into the composite caused different mechanical characteristics. Filler addition increased the elasticity modulus, toughness, thermal resistance increased, while the tensile strength decreased. ESP and AP fillers provided the best thermal resistance due to the relatively high thermal conductivity of ±1700 C compared to composites without fillers and amorphous ESP fillers. SEM observation supported the analysis of TF-polyester composite mechanical characteristics.

This study is aimed at uncovering the mechanism and role of the super hydrophobic characteristic of taro leaves on the process of hydrogen gas formation when there is a contact with a water droplet. The investigation was organized as: SEM-EDX analysis on the surface of taro leaf, observation on gas bubbles within a water droplet on the surface of taro leaves, and the detection of hydrogen gas production. The study result shows that the super hydrophobic characteristic of taro leaves caused the formation of great contact angle and high surface tension energy in droplets. A pointed-shaped nano texture caused the tension energy of the droplet surface to increase. As a result, particles randomly vibrate triggering the reaction between H 2 O droplets and Mg, K, and Ca on the surface of leaves producing hydrogen gas bubbles. Some gas was trapped in the nano grooves on the leaves surface and some with high pressure broke through the droplet and then were driven out by the Brownian motion.

Penelitian ini bertujuan untuk mengetahui kadar bioetanol terbaik dari kombinasi campuran ampas tebu dan kulit pisang dengan massa ragi 6 gram dan waktu fermentasi 72 jam, 96 jam dan 120 jam, menentukan waktu fermentasi yang optimal dan mengetahui kadar etanol sesuai SNI. Penelitian ini dilakukan dengan cara hidrolisis atau perebusan ampas tebu dan kulit pisang untuk memecah molekul menjadi dua bagian, kemudian proses fermentasi dilakukan dengan menggunakan Saccharomyces Cerevisae (yeast) dan proses destilasi dilakukan dengan menggunakan destilator untuk mendapatkan ethanol dari fermentasi yang kemudian diuji dengan Pen Refractometer untuk mengetahui ada tidaknya kadar etanol yang terbentuk dari proses destilasi. Sampel terbaik yang dipilih kemudian diuji kadar etanolnya menggunakan alat Gas Chromatography. Sehingga rendemen etanol terbaik yang dapat dikategorikan mencapai SNI adalah kombinasi ampas tebu 100% - kulit pisang 0% dengan ragi 6 gram dan waktu fermentasi 96 jam menghasilkan etanol sebesar 95,53%. This study aims to determine the best levels of bioetanol from a combination of bagasse and banana peel mixtures with 6 gram yeast mass and 72 hours, 96 hours and 120 hours fermentation time, to determine the optimum fermentation time and to know ethanol levels according to SNI. This research was carried out by hydrolysis or boiling of bagasse and banana peel to break down the molecules into two parts, then the fermentation process was carried out using Saccharomyces Cerevisae (yeast) and the distillation process was carried out using a destilator to obtain ethanol from fermentation which was then tested by means of Pen Refractometer to find out whether there is an ethanol level formed from the distillation process. The best sample selected was then tested for ethanol content using the Gas Chromatography tool. So that the best ethanol yield that can be categorized as achieving in SNI is a combination of 100% bagasse – 0% banana peel with 6 gram yeast and 96 hour fermentation time of ethanol produced at 95.53%.

The rapid population growth has an impact on the increasing need for drinking water. In swamp areas, the need for drinking water cannot be met immediately because it still contains organic compounds that make the water unfit for consumption. Peat water contains dissolved organic compounds that cause the water to turn brown and have an acidic character, so it needs special processing before it is ready for consumption. For peat water to be used by the community for drinking water, it is necessary to find an easy and cheap way to treat peat water. The use of a filtration device is one of the solutions that must be done in peat water treatment. The purpose of this study was to determine the effect of flow patterns, speed, and pressure on the filtration process with variations in the type of membrane and filtration arrangement. This research method was carried out by simulation using ANSYS 14.5 series. The simulation process begins with designing a filtration device with the following types: two-filter, three-filter, and four-filter. Then the simulation was performed by entering the value of the peat water properties into the regulatory equation. The results of this study indicate that the collaboration of two membranes with different holes in type-2 and 3 filters produces a good filtration rate. However, in type-4 filters, the use of a similar membrane is highly recommended. This filtration rate is influenced by the presence of a cross-flow reversal (CFR) region that appears, when using different filtration membranes at low pressure it doesn't matter. However, in other cases of systems operating at high pressure, CFR that appears tends to decrease the filtration rate, this is because CFR inhibits the flow rate in the filtration process

This study aims to determine the best bioethanol levels from a combination of cassava and pineapple peels mixture with variations of yeast mass as much as 11 grams, 13 grams, 15 grams and 72 hours fermentation time, to determine the optimal yeast mass and determine ethanol levels according to SNI. This research was carried out by hydrolysis using distilled water for 30 minutes, then fermentation using yeast and distillation process, then tested with a Refractometer Pen. Selected samples will be tested for ethanol content using the Gas Chromatography tool. The highest ethanol content of ethanol making with a combination of cassava and pineapple peels is for a combination of 75% cassava peel -25% pineapple peel 88.6% in a 15 gram yeast mass, a combination of 50% cassava peel -50% pineapple peel 89.3% in 15 gram yeast mass. So it can be concluded that the ethanol content of the combination of cassava and pineapple peels is not included in the category of Indonesian national standards (SNI).

This study studied the best levels of bioethanol from a combination of cassava peel and pineapple peel mixtures with 6 gram yeast mass and 72 hours, 96 hours and 120 hours fermentation time, to determine the optimal fermentation time and find ethanol levels according to SNI. This research was carried out by hydrolysis or cassava peel and pineapple peel using aquades for 30 minute to break the molecule into two parts, then carried out the fermentation process using Saccharomyces Cerevisae (yeast) and the distillation process using a destilator to obtain ethanol for fermentation then tested with a Refractometer to determine whether there is an ethanol level formed from the distillation process. The best sample selected was then tested for ethanol content using the Gas Chromatography tool. The results of this study are known by using the Gas Chromatography tool to determine the ethanol content contained in the distilled sample, the highest ethanol content of each combination. So that the best ethanol yield from a combination of 100% cassava peel -0% Pineapple Peel with a duration of 120 hours fermentation producing ethanol of 89.81% is still not included in the SNI category. I. PENDAHULUANMenipisnya cadangan bahan bakar fosilsdan semakin meningkatnya populasi manusiamsangat berpengaruh terhadap kebutuhanmenergi bagi kelangsungan hidup manusia. Sejak limaatahun terakhir, Indonesia mengalami dampak penurunan produksi minyak nasional. padahal dengan menambahnya jumlah penduduk indonesia, semakin meningkat pulaakebutuhan akannsarana transportasi dan aktivitas industri. Hal ini berakibat pada peningkatan kebutuhan dan konsumsi bahan bakar minyak.Oleh karena ituvsudah saatnyaauntuk Indonesiaamencari alternatif lain, dimana sumber energi fosil yang sifatnya tidak terbarukannberalih ke sumber energi berbahan baku nabatiyyang sifatnya terbarukan. Sebagai negara agraris danntropis, Indonesia telah dianugerahi kekayaannalam yang melimpah yang dapat dimanfaatkan sebagai bioenergi. Bahan bakar berbasis nabati salah satu contohnya adalah bioetanol. Bioetanol merupakan senyawa alkohol yang diperolehmlewat proses fermentasi biomassa dengan bantuan mikroorganisme. Bioetanol dapat dibuattdari sumber daya hayatiyyang sangat melimpah di Indonesia contohnyaddari bahan-bahan bergula atau pati seperti Kuluit singkong, Kulit nanas, tebu, nira, sorgum, ubi jalar, dan lain-lain. Semuanya merupakan tanaman yang memiliki karbohidrat dan mudah ditemukan di indonesia karena keadaan tanah dan iklim yang sangat mendukung.

This study aims to determine the levels of bioethanol from (cassava, black sticky rice, and white sticky rice) with the addition of 10 grams of yeast mass, with a variation of fermentation time of 48 hours, 72 hours and 96 hours and knowing the ethanol levels in accordance with National Standards Indonesia (SNI). This research was carried out by hydrolysis or boiling of ingredients (cassava, black sticky rice, and white sticky rice) using 800 ml of distilled water with 30 minutes, then fermentation using yeast or (saccharomyces cereviseae) and distillation using a tool. Complete destilator to obtain ethanol from fermentation results which is then tested with a pen refractometer to determine whether or not ethanol is formed from the distillation process. The samples were then tested for ethanol content using the Gas Chromatography tool. The results of this study are known by conducting a test using the Gas Chromatography tool to determine the ethanol content contained in the distilled sample. The results of cassava ethanol content with 72 hours fermentation time with ethanol were 98.41%, black sticky rice with 96 hours fermentation time the ethanol content was 94.96%, and white sticky rice with 96 hours fermentation time the ethanol content was 96.67%. PENDAHULUANBahan bakar fosil (minyak bumi, gas dan batu bara) sebagai sumber energi yang tidak terbarukan memiliki banyak masalah, terutama kenaikan harga (price escalation) secara global setiap terjadi krisis energi akibat dari faktor-faktor seperti cadangan yang berkurang sesuai dengan umur eksploitasinya. Permintaan yang meningkat, jaminan pasokan (supply security) yang terbatas dan pembatasan produksi pada penilaian dampak lingkungan yang ketat terhadap pemanasan global (global warming), harus dikurangi ketergantungannya. Solusi dalam permaslahan ini adalah menggunakan sumbersumber energi lainnya sebagai bahan bakar alternatif.Bioetanol merupakan salah satu sumber bahan bakar alternatif yang diolah dari tumbuhan, dimana memiliki keunggulan mampu menurunkan emisi CO 2 hingga 18 %. Menurut Balai Besar Teknologi Pati (B2TP) ada 3 kelompok tanaman sumber bioetanol yaitu: tanaman yang mengandung pati (seperti singkong, kelapa sawit, tengkawang, kelapa, kapuk, jarak pagar, rambutan, sirsak, malapari, dan nyamplung), bergula (seperti tetes tebu atau molase, nira aren, nira tebu, dan nira surgum manis) dan serat selulosa (seperti batang sorgum, batang pisang, jerami, dan kayu).Dalam pembuatan bioetanol karbohidrat merupakan bahan baku yang menunjang dalam proses fermentasi, dimana prinsip dasar fermentasi adalah degradasi komponen pati oleh enzim (Rustriningsih, 2007). Fermentasi

Ballistic limit is a speed limit where projectile with a certain shape, angle of attack and size is not able to perforate a target with certain properties and thickness. This paper aims is to determine and analyze the ballistic limit of commercial medium carbon steel plate which has been hardened by induction heating by using finite element based simulation. A plate with a thickness of 8 mm was shot by a deformable blunt projectile with a diameter of 20 mm, a length of 80 mm and a mass of 0.197 kg with an angle of attack of 90° against the plate. Simulation results show that projectile with a speed of 225 m s−1 is still able to penetrate the plate in the form of plugging. The plate can withstand the projectile rate at a maximum speed of 215 m−1. At this speed, the plate is damaged but the projectile does not penetrate. The plate still has ductility properties, as during the simulation there were deflection and bulge in the back side.