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Full-Text Articles in Mechanical Engineering

Optimation Of Nitrogen And Phosphorus In Azolla Growth As Biofertilizer, Hany Handajani Nov 2011

Optimation Of Nitrogen And Phosphorus In Azolla Growth As Biofertilizer, Hany Handajani

Makara Journal of Technology

Nitrogen is one of the most important minerals for living organisms. Azolla is known as a small water fern which can fix nitrogen through the symbiotic association with the blue green algae Anabaena. Experimental studies were carried out in the glass house, investigating the growth of Azolla using different levels of nitrogen and phosphorus in the media. The experiment used 12 treatments with 3 levels of nitrogen (0, 5, and 10 mg atom/L) and 4 levels of phosphorus (0, 10, 20, and 30 mg atom/l) in a factorial design with 3 replicates. The results show that the highest biomass for …


Establishment Code Hand Palm (Palm Code) 2d Gabor-Based Method, I Ketut Gede Darma Putra, Wira Bhuana, Erdiawan Erdiawan Nov 2011

Establishment Code Hand Palm (Palm Code) 2d Gabor-Based Method, I Ketut Gede Darma Putra, Wira Bhuana, Erdiawan Erdiawan

Makara Journal of Technology

Establishment Code Hand Palm (Palm Code) 2D Gabor-Based Method. Palmprint is relatively new in physiological biometrics. Palmprint ROI segmentation and feature extraction are two important issues in palm print recognition. This paper introduces two steps in the center of mass moment method for ROI segmentation that will be applied in the Gabor 2D filter to obtain palm code as palmprint feature vector. Normalized Hamming distance was used to measure the similarity degrees of two feature vectors of palmprint. The system was tested using database 1000 palmprint images generated from 5 samples from each of the 200 persons randomly selected with …


The Effectiveness Of Anaerobic Baffled Reactor And Rotating Biological Contactor In Batik Wastewater Treatment, Augustinus Ignatius Kristijanto, Widhi Handayani, Purwanti Asih Anna Levi Nov 2011

The Effectiveness Of Anaerobic Baffled Reactor And Rotating Biological Contactor In Batik Wastewater Treatment, Augustinus Ignatius Kristijanto, Widhi Handayani, Purwanti Asih Anna Levi

Makara Journal of Technology

Batik is one of popular arts of Indonesia. The batik industries in Sragen, Central Java, are prepared to compete in global market. In order to realize that objective, batik products should fulfill some qualifications, one of which is “environmental friendliness”. As batik production is usually generating wastewater which pollutes the environment, the technology of wastewater treatment should be developed to solve the problem. This preliminary study has been done to assess the effectiveness of anaerobic baffled reactor (ABR) and rotating biological contactor (RBC) in batik wastewater treatment. In 40 days of treatment period, the ABR performance in reducing pollutants showed …


Antibacterial Activity Of Papaya Leaf Extracts Against Pathogenic Bacteria, Elisa Friska Romasi, Jessica Karina, Adolf Jan Nexson Parhusip Nov 2011

Antibacterial Activity Of Papaya Leaf Extracts Against Pathogenic Bacteria, Elisa Friska Romasi, Jessica Karina, Adolf Jan Nexson Parhusip

Makara Journal of Technology

It was reported that the extracts of papaya leaves could inhibit the growth of Rhizopus stolonifer. Antibacterial activity of Carica papaya leaf extracts on pathogenic bacteria was observed in this study. Papaya leaves were extracted by using maceration method and three kinds of solvents: ethanol, ethyl acetate, and hexane. Papaya leaf extracts were tested against Bacillus stearothermophilus, Listeria monocytogenes, Pseudomonas sp., and Escherichia coli by agar diffusion method. The objectives of this study were to determine extract ability against pathogenic bacteria, to observe the influence of pH, NaCl, and heat on extracts ability, and to observe extract ability against B. …


Analytical And Computational Simulation Approaches To Design Low Energy Glass Block, Floriberta Binarti, Agustinus Djoko Istiadji, Prasasto Satwiko, Priyo Tri Iswanto Nov 2011

Analytical And Computational Simulation Approaches To Design Low Energy Glass Block, Floriberta Binarti, Agustinus Djoko Istiadji, Prasasto Satwiko, Priyo Tri Iswanto

Makara Journal of Technology

Analytical and Computational Simulation Approaches to Design Low Energy Glass Block. An environmentally friendly process was developed to produce a low embodied energy glass block from waste glasses. The energy efficiency of the glass block is represented by its thermal conductance (U) <3.177 W/m2.K and solar transmittance (SHGC) ≤0.25 as well as visible light transmission (VT) ≥0.27. A cavity was applied to reduce U value while insignificantly reducing VT. Analytical method was used to calculate the U value of glass blocks, ignoring the effect of convection. Ecotect program was used to analyze light level (VT) and heat load (SHGC) of each model. Effect of convection was simulated using a CFD program, which showed air velocity inside the cavity and temperature gradient in glass blocks. Comparing to an application with 3 mm float glass, energy efficiency obtained through applying the glass blocks could reach 96%. This simulation study ignored the presence of adhesive among glass layers that potentially reduces the VT and the SHGC of the glass blocks.


Flexible Connection Elastomeric Rubber As A Pounding Resisting Element Between Two Adjacent Buildings, Yuskar Lase, James Jatmiko Oetomo Nov 2011

Flexible Connection Elastomeric Rubber As A Pounding Resisting Element Between Two Adjacent Buildings, Yuskar Lase, James Jatmiko Oetomo

Makara Journal of Technology

Flexible Connection Elastomeric Rubber as a Pounding Resisting Element between Two Adjacent Buildings To solve pounding problem of two adjacent buildings, structural designer usually employs a dilatation between the structures or make the two structures as a monolith structure. Other alternative is by using an elastomeric rubber as a pounding resisting element between the two structures. Effectiveness in applying elastomeric rubber component as flexible connection of two adjacent structures is the main focus of this paper. Various simulations such as structure models, earthquake excitations and openings in gap element are studied. Observation of maximum structural responses will be performed for …


Effect Of Copper Addition On Mechanical Properties And Electrical Conductivity Of Pp/C-Cu Bipolar Plate Composites, Anne Zulfia, Taufik Abimanyu, Verina Warga Dalam Nov 2011

Effect Of Copper Addition On Mechanical Properties And Electrical Conductivity Of Pp/C-Cu Bipolar Plate Composites, Anne Zulfia, Taufik Abimanyu, Verina Warga Dalam

Makara Journal of Technology

Effect of Copper Addition on Mechanical Properties and Electrical Conductivity of PP/C-Cu Bipolar Plate Composites. Bipolar plate is a major component in PEM fuel cell which possess main function of collecting and removing electrons from anode to cathode. Therefore, materials for bipolar plates produced must have high electrical conductivity. To obtain bipolar plate materials which is cheap, lightweight and high conductivity, so it is developed bipolar plates material based on PP/C-Cu composite. PP/C-Cu composites has been made by mixing all materials then compounding, rheomix, hot blending and hot press. Cu (Copper) has been used various from 0.1 wt%, 1 wt% …


Medium Density Fibreboard Made Of Acetylated Sludge From Paper Mill, Luthfi Hakim, Evalina Herawati, I Nyoman Jaya Wistara Nov 2011

Medium Density Fibreboard Made Of Acetylated Sludge From Paper Mill, Luthfi Hakim, Evalina Herawati, I Nyoman Jaya Wistara

Makara Journal of Technology

Medium Density Fibreboard Made of Acetylated Sludge from Paper Mill. Research of using sludge as raw material for making medium density fibreboard (MDF) was useful to create additional value of sludge. The objective of the research was to evaluate physical properties, mechanical properties, and durability of MDF from acetylated sludge in 4 levels of acetate anhydride (0%, 3%, 5%, and 7%) with 3 replicates. The MDF was made using dry process. After materials were mixed with adhesives, they were pressed using hotpress under 170 oC temperature and 45 Pa pressure for 25 minutes. The size of the MDF sample was …


Application Of Empirical Orthogonal Function Models To Analyze Shoreline Change At Bangkalan Madura, Darius Arkwright, Suntoyo Suntoyo Nov 2011

Application Of Empirical Orthogonal Function Models To Analyze Shoreline Change At Bangkalan Madura, Darius Arkwright, Suntoyo Suntoyo

Makara Journal of Technology

Bangkalan’s shoreline, especially on the opposite side of Surabaya, has been evaluated to determine the morphological changes due to wave attack, near-shore current, long-shore sediment transport and coastal configuration. This research aims to determine the dominant patterns of variation of Bangkalan’s shoreline change, expressed by Eigen-function in empirical orthogonal function (EOF) models. That was started with data collection such as oceanographic data (wave and tidal), bathymetry and topographic map and sediment data. All data was used for forecasting two-monthly shoreline. Coordinate of two-monthly shoreline was used as input of EOF model. The first Eigen mode is a profile of shoreline …


Alos/Palsar Image Processing Using Dinsar And Log Ratio For Flood Early Detection In Jakarta Based On Land Subsidences, Dodi Sudiana, Mia Rizkinia Nov 2011

Alos/Palsar Image Processing Using Dinsar And Log Ratio For Flood Early Detection In Jakarta Based On Land Subsidences, Dodi Sudiana, Mia Rizkinia

Makara Journal of Technology

Flood that occurred in Jakarta is not only influenced by rainfall, urban planning system and drainage alone, but also may be involved land subsidence (LS). LS is possible in because Jakarta stands on top of layers of sediments and the presence of ground water consumption in very large quantities. In this research, the Advanced Land Observing Satellite (ALOS)/Phased Array type L-band Synthetic Aperture Radar (PALSAR) data was processed to determine the level of LS in Jakarta area and its relation to flood potential area. Differential interferometry method (DInSAR) was performed on two PALSAR data with different acquisition years, i.e. 2007 …


Flutter Analysis Of Rx-420 Balistic Rocket Fin Involving Rigid Body Modes Of Rocket Structures, Novi Andria Nov 2011

Flutter Analysis Of Rx-420 Balistic Rocket Fin Involving Rigid Body Modes Of Rocket Structures, Novi Andria

Makara Journal of Technology

Flutter Analysis of RX-420 Balistic Rocket Fin Involving Rigid Body Modes of Rocket Structures. Flutter is a phenomenon that has brought a catastrophic failure to the flight vehicle structure. In this experiment, flutter was analyzed for its symmetric and antisymmetric configuration to understand the effect of rocket rigid modes to the fin flutter characteristic. This research was also expected to find out the safety level of RX-420 structure design. The analysis was performed using half rocket model. Fin structure used in this research was a fin which has semispan 600 mm, thickness 12 mm, chord root 700 mm, chord tip …


Physical Characterization And Desulfurization Of Biobriquette Using Calcium-Based Adsorbent, Mahidin Mahidin, Asri Gani, Khairil Khairil Nov 2011

Physical Characterization And Desulfurization Of Biobriquette Using Calcium-Based Adsorbent, Mahidin Mahidin, Asri Gani, Khairil Khairil

Makara Journal of Technology

Combustion of coal and co-combustion of their co-fuel contribute to gas emissions. Among the gas emissions are SOx, NOx, CO and CO2. Introduction of calcium based adsorbent is addressed to absorb SO2 that release to the atmosphere during the combustion process. Objective of the research is at first to observe the physical characteristics of biobriquettes as a function of briquette compositions (coal to palm kernel shell ratios) and Ca/S ratios (Ca in adsorbent and S in briquette) using a natural adsorbent (shellfish waste). The second objective is to investigate desulfurization characteristics as a function of Ca/S ratios and desulfurization temperatures …


Application Of Principal Component Proximity Transform And Geostatistics Methods For Volume Shale Distribution As Reservoir Characreristic Imaging In Seismic 3d, Nur Islami Nov 2011

Application Of Principal Component Proximity Transform And Geostatistics Methods For Volume Shale Distribution As Reservoir Characreristic Imaging In Seismic 3d, Nur Islami

Makara Journal of Technology

Application of Principal Component Proximity Transform and Geostatistics Methods for Volume Shale Distribution as Reservoir Characreristic Imaging in Seismic 3D. Principal component proximity transform (PCPT) technique was used to predict the content of volume shale into seismic data in reservoir modeling framework. The goal in this research is to get the volume shale imaging in three dimensions and allow for reservoir modelling. The reservoir modelling requires an integrated quantitative and qualitative data sources collected separately, such as well and seismic data. Integrating PCPT and Geostatistic methods can generate the detail information for characterization of reservoir’s properties. Finally, it shows that …


Improvement Of High Temperature Oxidation Of Low Carbon Steel Exposed To Ethanol Combustion Product At 700 °C By Hot-Dip Aluminizing Coating, Mohammad Badaruddin Nov 2011

Improvement Of High Temperature Oxidation Of Low Carbon Steel Exposed To Ethanol Combustion Product At 700 °C By Hot-Dip Aluminizing Coating, Mohammad Badaruddin

Makara Journal of Technology

Low carbon steel (AISI 1005) was coated by hot-dipping into a molten Al-10% Si bath at 700 °C for 18s. After hotdipping treatment, the coating layers consisted of Al, Si, FeAl3, τ5-Fe2Al8Si, and Fe2Al5. The bare steel and the aluminized steel were isothermally oxidized at 700 °C in ethanol combustion product at atmospheric pressure for 49 h. The aluminized steel shows good performance in high temperature oxidation because the formation of Al2O3 layer on the coating surface. The growth of iron oxide nodules on the surface coating was accelerated by rapid outward diffusion of Fe-ions due to the presence of …


Cassava Pulp As A Biofuel Feedstock Of An Enzymatic Hydrolysis Proces, Djuma’Ali Djuma’Ali, Nonot Soewarno, Sumarno Sumarno, Dyah Primarini, Wahono Sumaryono Nov 2011

Cassava Pulp As A Biofuel Feedstock Of An Enzymatic Hydrolysis Proces, Djuma’Ali Djuma’Ali, Nonot Soewarno, Sumarno Sumarno, Dyah Primarini, Wahono Sumaryono

Makara Journal of Technology

Cassava pulp, a low cost solid byproduct of cassava starch industry, has been proposed as a high potential ethanolic fermentation substrate due to its high residual starch level, low ash content and small particle size of the lignocellulosic fibers. As the economic feasibility depends on complete degradation of the polysaccharides to fermentable glucose, the comparative hydrolytic potential of cassava pulp by six commercial enzymes were studied. Raw cassava pulp (12% w/v, particle size <320 >μm) hydrolyzed by both commercial pectinolytic (1) and amylolytic (2) enzymes cocktail, yielded 70.06% DE. Hydrothermal treatment of cassava pulp enhanced its susceptibility to enzymatic cleavageas compared …


The Formation Design Of Noise Reducers From Plywood, Foam, Tray, Dan Coconut Fiber For Static Sources, Melati Ferianita Fachrul, Wisnu Eka Yulyanto, Asharani Merya Apr 2011

The Formation Design Of Noise Reducers From Plywood, Foam, Tray, Dan Coconut Fiber For Static Sources, Melati Ferianita Fachrul, Wisnu Eka Yulyanto, Asharani Merya

Makara Journal of Technology

The Formation Design of Noise Reducers from Plywood, Foam, Tray, dan Coconut Fiber for Static Sources. Research was conducted in a semi-anechoic room using a method referring to the ISO 3745. The design used is the Hemisphere in which the source of noise is analogous to engines in an industry. The value reduction in the rate of sound power is obtained by comparing the sound power level before and after control is given. The noise control test materials used consist of layers of plywood, foam, fiber and tray (egg box). The effectiveness of these materials is tested by measuring the …


Production Of Lovastatin And Sulochrin By Aspergillus Terreus Using Solid State Fermentation, Rizna Triana Dewi, Nina Artanti, Hani Mulyani, Puspa Dewi Narrij Lotulung, Minarti Minarti Apr 2011

Production Of Lovastatin And Sulochrin By Aspergillus Terreus Using Solid State Fermentation, Rizna Triana Dewi, Nina Artanti, Hani Mulyani, Puspa Dewi Narrij Lotulung, Minarti Minarti

Makara Journal of Technology

Lovastatin is an anti-cholesterol agent that was produced by Aspergillus terreus using solid state fermentation (SSF). During this fermentation process, sulochrin is also produced as an unwanted co-metabolite. However, our previous result showed that sulochrin had potential as antidiabetes because it is an inhibitor agent of α-glucosidase. In this paper, we reported our observation on lovastatin and sulochrin production pattern in relation with inhibitor α-glucosidase activity during eleven days fermentation of A. terreus koji (SSF) ethyl acetate extract. Koji obtained from solid state fermentation with rice as the substrate and incubated at room temperature, sample is taken daily for eleven …


The Zonation Of Abration Speed Characteristics And Its Handling Technique Of Jalinbar Of North Bengkulu As Vital Band Transportation, Suwarsono Suwarsono, Supiyati Supiyati, Suwardi Suwardi Apr 2011

The Zonation Of Abration Speed Characteristics And Its Handling Technique Of Jalinbar Of North Bengkulu As Vital Band Transportation, Suwarsono Suwarsono, Supiyati Supiyati, Suwardi Suwardi

Makara Journal of Technology

The Zonation of Abration Speed Characteristics and its Handling Technique of Jalinbar of North Bengkulu as Vital Band Transportation. Jalinbar Bengkulu is a vital infrastructure for traffic service, goods, agriculture products, mining, plantation and oils distribution. Abration due to scour of seawater often make these roads jammed and discrupts the peoples economy movement. The aims of this research was to investigate the abration speed of all segment of Jalinbar. The research method was a combination of two methods: A determination of swash energy of sea water using photometer and determination of rocks binding energy using douche method. The result shows …


Determining The Standard Value Of The Oily Distortion Of Acquisition The Fingerprint Images, Rahmat Syam, Mochamad Hariadi, Mauridhi Hery Purnomo Apr 2011

Determining The Standard Value Of The Oily Distortion Of Acquisition The Fingerprint Images, Rahmat Syam, Mochamad Hariadi, Mauridhi Hery Purnomo

Makara Journal of Technology

Determining the Standard Value of the Oily Distortion of Acquisition the Fingerprint Images. This research describes a novel procedure for determining the standard value of the oily distortion of acquisition the fingerprint images based on the score of clarity and ridge-valley thickness ratio. The fingerprint image is quantized into blocks size 32 x 32 pixels. Inside each block, an orientation line, which perpendicular to the ridge direction, is computed. The center of the block along the ridge direction, a two-dimension (2-D) vector V1 (slanted square) with the pixel size 32 x 13 pixels can be extracted and transformed to a …


Ergonomic Analysis Of Garment Industry Using Posture Evaluation Index (Pei) In Virtual Environment, Erlinda Muslim, Boy Nurtjahyo, Romadhani Ardi Apr 2011

Ergonomic Analysis Of Garment Industry Using Posture Evaluation Index (Pei) In Virtual Environment, Erlinda Muslim, Boy Nurtjahyo, Romadhani Ardi

Makara Journal of Technology

Ergonomic Analysis of Garment Industry using Posture Evaluation Index (PEI) in Virtual Environment. This research tried to study, in a virtual environment, the ergonomics of four divisions in garment industry: cutting division, sewing division, button division, and finishing division. Variables that influence the working conditions in each division are different; depend on the real situations that happened. The purpose is to assess the real working conditions based on ergonomics study using Posture Evaluation Index (PEI). PEI integrates the scores of low back analysis (LBA), ovako working posture (OWAS), and rapid upper limb assessment (RULA). Analysis phase was done using digital …


The Solvent Effectiveness On Extraction Process Of Seaweed Pigment, Warkoyo Warkoyo, Elfi Anis Saati Apr 2011

The Solvent Effectiveness On Extraction Process Of Seaweed Pigment, Warkoyo Warkoyo, Elfi Anis Saati

Makara Journal of Technology

Eucheuma cottonii seaweed is a species of seaweed cultured in Indonesian waters, because its cultivation is relatively easy and inexpensive. It has a wide variety of colors from green to yellow green, gray, red and brown, indicating photosynthetic pigments, such as chlorophyll and carotenoids. An important factor in the effectiveness of pigment extraction is the choice of solvent. The correct type of solvent in the extraction method of specific natural materials is important so that a pigment with optimum quality that is also benefical to the society can be produced. The target of this research is to obtain a high …


Two-Class Classification With Various Characteristics Based On Kernel Principal Component Analysis And Support Vector Machines, Ivanna Kristianti Timotius, Iwan Setyawan, Andreas Ardian Febrianto Apr 2011

Two-Class Classification With Various Characteristics Based On Kernel Principal Component Analysis And Support Vector Machines, Ivanna Kristianti Timotius, Iwan Setyawan, Andreas Ardian Febrianto

Makara Journal of Technology

Two class pattern classification problems appeared in many applications. In some applications, the characteristic of the members in a class is dissimilar. This paper proposed a classification system for this problem. The proposed system was developed based on the combination of kernel principal component analysis (KPCA) and support vector machines (SVMs). This system has been implemented in a two class face recognition problem. The average of the classification rate in this face image classification is 82.5%.


Are Ieee 754 32-Bit And 64-Bit Binary Floating-Point Accurate Enough?, Bernaridho Hutabarat, I Ketut Eddy Purnama, Mochamad Hariadi, Mauridhi Hery Purnomo Apr 2011

Are Ieee 754 32-Bit And 64-Bit Binary Floating-Point Accurate Enough?, Bernaridho Hutabarat, I Ketut Eddy Purnama, Mochamad Hariadi, Mauridhi Hery Purnomo

Makara Journal of Technology

This paper describes a research toward the accuracy of floating-point values, and effort to reveal the real accuracy. The methods used in this research paper are assignment of values, assignment of value of arithmetic expressions, and output the values using floating-point value format that helps reveal the accuracy. The programming-tool used are Visual C# 9, Visual C++ 9, Java 5, and Visual BASIC 9. These tools run on top of Intel 80 x 86 hardware. The results show that 1*10-x cannot be accurately represented, and the approximate accuracy ranges only from 7 to 16 decimal digits.


The Synergy Of Recombinant Xylanolytic Enzyme On Xylan Hydrolysis, One Asmarani, Bambang Prajogo Eko Wardojo, Ni Nyoman Tri Puspaningsih Apr 2011

The Synergy Of Recombinant Xylanolytic Enzyme On Xylan Hydrolysis, One Asmarani, Bambang Prajogo Eko Wardojo, Ni Nyoman Tri Puspaningsih

Makara Journal of Technology

Microbial xylanases or xylanolytic enzyme have received considerable attention over the last years owing to a multitude of possible applications. These enzymes have potential in the biodegradation of lignocellulosic biomass to fuels, chemicals, fruit juice, animal feed and in improving rumen digestion. More recently, the use of xylanases as bleaching agent in the pulp and paper industry has been suggested to replace of some of the chemicals presently used for this purpose. Such applications could have an important positive impact on the environment. The purpose of this research was determining the synergy of 3 recombinant xylanolytic enzymes (β-xylosidase, exo-xylanase and …


An Investigation Into The Resistance/Powering And Seakeeping Characteristics Of River Catamaran And Trimarana, Murdijanto Murdijanto, I Ketut Aria Pria Utama, Andi Jamaluddin Apr 2011

An Investigation Into The Resistance/Powering And Seakeeping Characteristics Of River Catamaran And Trimarana, Murdijanto Murdijanto, I Ketut Aria Pria Utama, Andi Jamaluddin

Makara Journal of Technology

The increase of fuel price has caused fleet operational and shipping business to be in danger situation. The fuel consumption of a ship is influenced by ship volume or wetted area which contributes directly to the increase of ship resistance and the size of main engine. In order to find out the appropriate answers, a series of investigation into river transportation using monohull, catamaran and trimaran types of vessel was carried out. The work focused on the estimation of total resistance and powering as well as seakeeping characteristics and carried out experimentally using tank test and numerically using a ship …


Natural Gas As Petroleum Fuel Substitution: Analysis Of Supply-Demand Projections, Infrastructures, Investments And End-User Prices, Abdul Qoyum Tjandranegara, Arsegianto Arsegianto, Widodo Wahyu Purwanto Apr 2011

Natural Gas As Petroleum Fuel Substitution: Analysis Of Supply-Demand Projections, Infrastructures, Investments And End-User Prices, Abdul Qoyum Tjandranegara, Arsegianto Arsegianto, Widodo Wahyu Purwanto

Makara Journal of Technology

The petroleum fuels (PF) subsidy has long burdens the government spending, and discourages less expensive energy usage such as natural gas (NG). Exporting NG and importing the more expensive PF products cause financial losses to Indonesia. The lack of NG infrastructure is the main hurdle in maximizing domestic NG usage and so does the perception of its high investment costs burdening government spending and pushing the NG transportation cost up. This study calculates the required NG infrastructure and its investments for several levels of PF substitutions up to 2030. To balance the NG demands, the supply from each field and …


Formation Of Caco3 Particle And Conductivity Of Na2co3 And Cacl2 Solution Under Magnetic Field On Dynamic Fluid System, Nelson Saksono, Setijo Bismo, Roekmijati Widaningroem, Azwar Manaf Apr 2011

Formation Of Caco3 Particle And Conductivity Of Na2co3 And Cacl2 Solution Under Magnetic Field On Dynamic Fluid System, Nelson Saksono, Setijo Bismo, Roekmijati Widaningroem, Azwar Manaf

Makara Journal of Technology

Hard water causes the CaCO3 scale formation on the pipe walls and heat exchanger equipments in industrial or domestic water processes. A great number of experimental researches on the prevention of the CaCO3 precipitation process by magnetic field have been carried out. In this research, Na2CO3 and CaCl2 solutions was magnetized in the circulated flow condition (dynamic fluid system). The velocity of fluid and the circulation time was modified to examine its influences to the magnetization process. CaCO3 content was measured by titration method of EDTA complexometry. Conductivity test was conducted to find out hydrate ion bonding. The results showed …


Cradle To Gate Simple Life Cycle Assessment Of Biodiesel Production In Indonesi, Akhmad Hidayatno, Teuku Yuri M. Zagloel, Widodo Wahyu Purwanto, Carissa Carissa, Lindi Anggraini Apr 2011

Cradle To Gate Simple Life Cycle Assessment Of Biodiesel Production In Indonesi, Akhmad Hidayatno, Teuku Yuri M. Zagloel, Widodo Wahyu Purwanto, Carissa Carissa, Lindi Anggraini

Makara Journal of Technology

The focus of this research is to analyze potential environmental impact in the supply chain of palm oil biodiesel industries. Simple Life Cycle Assessment (LCA) is applied to analyze impacts, produced by the three main units in the supply chain of Palm-Oil-based Biodiesel, which are Palm Plantation, CPO mill, and Biodiesel Plant. We developed LCA calculation model using spreadsheet software, used to assess a number of input scenarios to evaluate the best scenario, in variation of: land quality, land area and the rate of clearing, land clearing technique and type of the original land. The biggest potential environmental impact is …


Circuit Design For Sensor Detection Signal Conditioner Nitrate Content, Robeth Viktoria Manurung, Aminuddin Debataraja, Hiskia Hiskia Apr 2011

Circuit Design For Sensor Detection Signal Conditioner Nitrate Content, Robeth Viktoria Manurung, Aminuddin Debataraja, Hiskia Hiskia

Makara Journal of Technology

Circuit Design for Sensor Detection Signal Conditioner Nitrate Content. Nitrate is one of macro nutrients very important for agriculture. The availability of nitrate in soil is limited because it is very easy to leaching by rain, therefore nitrate could be contaminated ground water by over-process of fertilizer. This process could also produce inefficiency in agriculture if it happened continuesly without pre-analysis of farm field. The answer those problems, it is need to develop the ion sensor system to measure concentrations of nitrat in soil. The system is consist of nitrate ion sensor device, signal conditioning and data acquisition circuit. The …


Characterization Of Surface Active Shell Charcoal Nyamplung Seeds (Calophyllum Inophyllum Linn), Santiyo Wibowo, Wasrin Syafi, Gustan Pari Apr 2011

Characterization Of Surface Active Shell Charcoal Nyamplung Seeds (Calophyllum Inophyllum Linn), Santiyo Wibowo, Wasrin Syafi, Gustan Pari

Makara Journal of Technology

Characterization of Surface Active Shell Charcoal Nyamplung Seeds (Calophyllum inophyllum Linn). Chemical and physical activation of nyamplung shell with 0%, 5%, and 10% H3PO4 for 60 and 120 minutes has been carried out to prepare activated charcoal. The purpose of this experiment was to look into the characteristic of nyamplung shell activated charcoal surface. Nyamplung shell was carbonized into charcoal, then activated by immersion in H3PO4 solution using 0%, 5% and 10%, for 24 hours, and heated in retort at two temperatures (700 and 800 oC) and two duration (60 and 120 minutes). The material were characterized by fourier transform …