bluuebunny/crossref_metadata_2025 huggingface dataset:
Propagation of a global coronal wave and its interaction with large-scale coronal magnetic structures
Authors: Afanasyev A. N. , Zhukov A. N.
Published: March 2018

Context. Global coronal waves associated with solar eruptions (the so-called EIT waves) often encounter coronal holes and solar active regions and interact with these magnetic structures. This interaction leads to a number of observed effects such as wave reflection and transmission.

Aims. We consider the propagation of a large-scale coronal shock wave and its interaction with large-scale non-uniformities of the background magnetic field and plasma parameters.

Methods. Using the Lare2d code, we performed 2.5-dimensional simulations of the interaction of a large-scale single-pulse fast-mode magnetohydrodynamic shock wave of weak-to-moderate intensity with the region of enhanced Alfvén speed as well as with that of reduced Alfvén speed. We analysed simple models of non-uniformity and the surrounding plasma to understand the basic effects in wave propagation.

Results. We found the reflected waves of plasma compression and rarefaction, transmitted waves that propagate behind or ahead of the main part of the wave, depending on properties of the plasma non-uniformity, and secondary wave fronts. The obtained results are important to the correct interpretation of the global coronal wave propagation in the solar corona, understanding of theoretical aspects of the interaction of large-scale coronal shock waves with large-scale coronal magnetic structures, and diagnostics of coronal plasma parameters.
Probing midplane CO abundance and gas temperature with DCO+
in the protoplanetary disk around HD 169142
Authors: Carney M. T. , Fedele D. , Hogerheijde M. R. , Favre C. , Walsh C. , Bruderer S. , Miotello A. , Murillo N. M. , Klaassen P. D. , Henning Th. , van Dishoeck E. F.
Published: March 2018

Context. Physical and chemical processes in protoplanetary disks affect the disk structure and the midplane environment within which planets form. The simple deuterated molecular cation DCO+ has been proposed to act as a tracer of the disk midplane conditions.

Aims. This work aims to understand which midplane conditions are probed by the DCO+ emission in the disk around the Herbig Ae star HD 169142. We explore the sensitivity of the DCO+ formation pathways to gas temperature and CO abundance.

Methods. The DCO+ J = 3−2 transition was observed with Atacama Large Millimeter/submillimeter Array at a spatial resolution of ~0.3′′ (35 AU at 117 pc). We modeled the DCO+ emission in HD 169142 with a physical disk structure adapted from the literature, and employed a simple deuterium chemical network to investigate the formation of DCO+ through the cold deuterium fractionation pathway via H2D+. Parameterized models are used to modify the gas temperature and CO abundance structure of the disk midplane to test their effect on DCO+ production. Contributions from the warm deuterium fractionation pathway via CH2D+ are approximated using a constant abundance in the intermediate disk layers.

Results. The DCO+ line is detected in the HD 169142 disk with a total integrated line flux of 730 ± 73 mJy km s−1. The radial intensity profile reveals a warm, inner component of the DCO+ emission at radii ≲30 AU and a broad, ring-like structure from ~50–230 AU with a peak at 100 AU just beyond the edge of the millimeter grain distribution. Parameterized models show that alterations to the midplane gas temperature and CO abundance are both needed to recover the observed DCO+ radial intensity profile. The alterations are relative to the fiducial physical structure of the literature model constrained by dust and CO observations. The best-fit model contains a shadowed, cold midplane in the region z∕r < 0.1 with an 8 K decrease in Tgas and a factor of five CO depletion just beyond the millimeter grains (r = 83 AU), and a 2 K decrease in Tgas for r > 120 AU. The warm deuterium fractionation pathway is implemented as a constant DCO+ abundance of 2.0 × 10−12 between 30–70 K and contributes >85% to the DCO+ emission at r < 83 AU in the best-fit model.

Conclusions. The DCO+ emission probes a reservoir of cold material in the HD 169142 outer disk that is not probed by the millimeter continuum, the spectral energy distribution, nor the emission from the 12 CO, 13 CO, or C18O J = 2−1 lines. The DCO+ emission is a sensitive probe of gas temperature and CO abundance near the disk midplane and provides information about the outer disk beyond the millimeter continuum distribution that is largely absent in abundant gaseous tracers such as CO isotopologues.
Modelling the early time behaviour of type Ia supernovae: effects of the
56Ni distribution
Authors: Magee M. R. , Sim S. A. , Kotak R. , Kerzendorf W. E.
Published: March 2018

Recent studies have demonstrated the diversity in type Ia supernovae (SNe Ia) at early times and highlighted a need for a better understanding of the explosion physics as manifested by observations soon after explosion. To this end, we present a Monte Carlo code designed to model the light curves of radioactively driven, hydrogen-free transients from explosion to approximately maximum light. In this initial study, we have used a parametrised description of the ejecta in SNe Ia, and performed a parameter study of the effects of the 56Ni distribution on the observed colours and light curves for a fixed 56Ni mass of 0.6 M⊙. For a given density profile, we find that models with 56Ni extending throughout the entirety of the ejecta are typically brighter and bluer shortly after explosion. Additionally, the shape of the density profile itself also plays an important role in determining the shape, rise time, and colours of observed light curves. We find that the multi-band light curves of at least one SNe Ia (SN 2009ig) are inconsistent with less extended 56Ni distributions, but show good agreement with models that incorporate 56Ni throughout the entire ejecta. We further demonstrate that comparisons with full UV OIR colour light curves are powerful tools in discriminating various 56Ni distributions, and hence explosion models.
Bioelectricity Production from Microalgae-Microbial Fuel Cell Technology (MMFC)
Authors: da Costa Carlito , Hadiyanto
Published: March 2018

Microbial fuel cell is an ecological innovative technology producing bioelectricity by utilizing microbes activity. Substituent energy is produced by changing the chemical energy to electrical energy through the catalytic reaction of microorganism. The research aims to find out the potency of bioelectricity produced by microalgae microbial fuel cell technology by utilizing the combination of tapioca wastewater and microalgae cultivation. This research is conducted through the ingredients preparation stage – microalgae culture, wastewater characterization, membrane and graphite activation, and the providing of other supporting equipment. The next stage is the MMFC arrangement, while the last one is bioelectricity measurement. The result of optimal bioelectricity production on the comparison of electrode 2 : 2, the power density is 44,33 mW/m2 on day 6, meanwhile, on that of 1 : 1, 20,18 mW/m2 power density on day 1 is obtained. It shows that bioelectricity can be produced from the combination of tapioca wastewater and microalgae culture through the microalgae-microbial fuel cell (MMFC) technology.This research is expected to be a reference for the next research particularly the one that observes the utilizing of microalgae as the part of new and renewable energy sources.
Modification of Cassava Starch Using Lactic Acid Hydrolysis in The Rotary-UV Dryer to Improve Physichocemical Properties
Authors: Sumardiono Siswo , Jos Bakti , Firmansyah Denny , Hidayatunajah Rahmi , Pudjihastuti Isti
Published: March 2018

Food security should be supported in an effort to utilize local products into import substitution products. Cassava starch has the potential to be developed into semi-finished products in the form of flour or starch which does not contain gluten but can inflate large baking process, potentially as a substitute for wheat flour-the main ingredient for making bread. The characteristic of the starch is influenced by the type of starch composition and structure. Natural starch has physicochemical properties i.e. a long time cooking and pasta formed hard. These constraints allow us to modify cassava starch by a combination of lactic acid hydrolysis and drying with rotary UV system. Modified cassava starch is expected to be used as a substitute for wheat flour. The aim of the research which is a combination of lactic acid hydrolysis and drying using a rotary UV system is to examine the optimum operating conditions in the drying process of starch hydrolysis with parameter the physicochemical and rheological properties of modified cassava starch. The initial process study is to hydrolyze cassava starch using lactic acid. Furthermore, hydrolyzed cassava starch is then dried using UV light in the rotary dryers system. There are a variety of changing variables, i.e. time of irradiation cassava starch-lactic acid hydrolysis products in the rotary UV light and air drying temperature. The research results show that modified starch has a better characteristic than the natural starch. From the analysis, the best point of swelling power, solubility and baking expansion is consequently 15.62 g/g; 24.19 %; 2.21 ml/gr. The FTIR result shows that there is no significant difference of the chemical structure because the starch modification only change the physical characteristics. From the SEM analysis, we can know that the size of the starch’s granule changes between the natural starch and the modified starch..
Edible Coating from Green Tea Extract and Chitosan to Preserve Strawberry (Fragaria vesca L.)
Authors: Apriyanti Dwi , Rokhati Nur , Mawarni Novia , Khoiriyah Zuroidatul , Istirokhatun Titik
Published: March 2018

Food quality is an important factor in food sector. One way to increase the quality of food is by applying edible coating to slow down the degradation of foods quality. Combination of chitosan and green tea extract is one of the types of edible coating which many function as food preservative Green tea extract is chosen because of its high antioxidant contents. The goal of this research is to make a film from the composite of chitosan and green tea extract as a food coating and to observe the effect of chitosan concentration and the addition of green tea extract to the phenolic contents and antioxidant activity of the film. Moreover, this research also aims to apply chitosan film and green tea extract to foods, especially strawberries, and observing the effect of chitosan concentration and the addition of green tea extract to the shrinking of the fruit’s weight as well as its antimicrobial activities. Strawberries were coated with five different coating formula including one set as blank (uncoated fruit). The result of this research showed that the increasing of chitosan concentration and the volume of green tea extract addition also increase the antioxidant activity on the film. The phenolic contents on the green tea extract addition will also increase its phenolic contents as well. However, the increasing number of chitosan concentration can reduce the phenolic content on the film. Meanwhile, during the application to strawberries, it is found that 3% chitosan concentration which is combined with the addition of 2.5% green tea extract will minimize the shrinking of the fruit’s weight. Also 3% chitosan concentration will give a better antimicrobial activity. In the other side the addition of green tea extract will increase antioxidant activity, the addition of green tea extract also causing a decrease in antimicrobial activity.
The Effect of Emulsifier and Hydrocolloid on Baking Expansion and Texture of Bread from Modified Cassava
Authors: Pudjihastuti Isti , Handayani Noer , Sumardiono Siswo
Published: March 2018

Indonesia has a very abundant cassava that can be used instead of wheat. Bread made from cassava is safe for celiac sufferers, in which cannot tolerate a protein called gluten found in wheat flour. However, bread from cassava has the disadvantage that it cannot inflate perfectly. Our research goal is to study the effect of emulsifier and hydrocolloid concentration as modifying agents on baking expansion and bread texture (hardness). The test level hedonic preference for bread products results from modified tapioca is also necessary to know the level of customer satisfaction. This study were conducted by three main stages, modification of cassava, baking process, and analyses. Modification of cassava starch was applied using combination of lactic acid solution and ultra violet (UV) irradiation. Emulsifier (DATEM) and hydrocolloid (xanthan gum) were used in baking process. The addition of emulsifier and hydrocolloid can improve baking expansion. The addition of 7% emulsifiers on modified cassava can increase the volume of bread, taste, and texture so it can give greater satisfaction to consumers. Hydrocolloid can replace the function of gluten so the bread can inflate perfectly. The optimal composition of modified cassava in bread making is 25% of modified cassava and 75% of wheat flour. The low value of texture (hardness) on bread made from modified cassava indicated a better performance in comparison with native cassava. Baking expansion and texture of the bread is influenced by the modification process. Furthermore, the comprehensive and optimum studies of modification need to be investigated.
Calcium soap from palm fatty acid distillate (PFAD) for ruminant feed: quality of calcium source
Authors: Handojo Lienda A. , Indarto Antonius , Shofinita Dian , Meitha Anggina , Nabila Rakhmawati , Triharyogi Harry
Published: March 2018

Calcium soap is potentially used as fat supplements for ruminants since it contains high concentration of fat and calcium that are useful for ruminants. The consumption of calcium soap may increase the yield and the fat content of milk, as well as increase the ruminant’s fertility. Calcium soap can be produced from palm fatty acid distillate (PFAD), which is a by-product of crude palm oil (CPO) refining process, and calcium oxide (CaO). In this study, the effect of CaO quality on the acid value of the product has been observed. It was found that the reaction with lower concentration of active calcium of CaO resulted in products with a higher acid value, which indicates a lower reaction conversion. Thus, the produced calcium soap requires further treatment in order to remove the unreacted calcium and free fatty acid. Washing with hexane followed by either vacuum or convection drying has been found to be able to reduce the acid value of the product significantly.
The Synthesis of Magnesium Soaps as Feed for Biohydrocarbon Production
Authors: Pratiwi Meiti , Neonufa Godlief F. , Prakoso Tirto , Soerawidjaja Tatang H.
Published: March 2018

In previous study, by heating magnesium basic soaps from palm stearine will decarboxylated and produced biohydrocarbon. The frequent method to produced metal soaps from triglyceride in laboratory scale is metathesis. This process is less favored because this method would produced large amounts of salt waste and hard to develop into bigger scale. This study investigated the process and characterization of magnesium soaps from coconut oil and magnesium hydroxide via direct reaction method at 185 °C for 3 and 6 hours. The resulting soaps were washed with water and methanol, then dried. This process yield more than 80%-w metal soaps, acid values lower than 6 mg KOH/g and pH 9.2. Based on Thermogravimetry Analysis (TGA) and SEM results, the initial decomposition temperature of these metal soaps were at 300 °C and have amorphous surface morphology. From decarboxylation test of magnesium basic soaps indicate great potency as feed for biohydrocarbon production.
Biodiesel Production from Wet Spirulina sp. by One-Step Extraction-Transesterification
Authors: Surya Pradana Yano , Azwar Azmi Fariz , Masruri Wildan , Hartono Muhamad
Published: March 2018

Microalgae has gained immense interests as the raw material for biofuel production. The lipid content in microalgae can be converted into biodiesel through conventional method which involves separated process of extraction and transesterification. In this study, the production of biodiesel from Spirulina sp. was performed through one-step extraction-transesterification using KOH as base catalyst to simplify the production of biodiesel. The mixture of methanol-hexane was employed as both solvent and reactant in the process. The resulting biodiesel was found to be mainly composed of methyl oleate and methyl palmitate. On the other hand, increasing the reaction temperature and reducing the quantity of methanol in solvent mixture would also increase the yield of biodiesel. The optimum methanol-hexane volumetric ratio and temperature which gave the highest biodiesel yield were 3:7 and 50°C, respectively.
Manufacturing Carbon Material by Carbonization of Cellulosic Palm Oil Waste for Supercapacitor Material
Authors: Hendriansyah Reza , Prakoso Tirto , Widiatmoko Pramujo , Nurdin Isdiriayani , Devianto Hary
Published: March 2018

Palm oil waste as biomass resources in Indonesia were not fully utilized. One of the product that can be made from oil palm biomass is activated carbon. Activated carbon characteristic with high porosity and good conductivity, made activated carbon suitable as supercapacitor electrode material. Activated carbon preparation consists of two main steps that are carbonization and activation. In this research carbonization carried out by hydrothermal process while activation conducted by physcal activation. This research focused on manufacturing activated carbon from palm oil waste by hydrothermal carbonization for supercapacitor application. Activated carbon produced from empty fruit bunch have a surface area of 330 – 1181 m2/gr, pore volume of 0.19 – 0.69 cm3/gr, and pore size of 2.1 – 2.3 nm. While activated carbon produced from oil palm shell have surface area of 8 – 451 m2/gr, pore volume 0.05 – 1.064 cm3/gr, and pore size 2.9 – 20.7 nm. The crystallinity of the activated carbon obtained ranged from 46.5 to 51.9%. In this study, the activated carbon is used as a working electrode on an asymmetric hybrid supercapacitor with nickel oxide being used as second electrode. This palm oil-based supercapacitor cell has a capacitance of 1.7554 F/g.
Reduction of P2O5 and F from Phosphogypsum by CaO addition
Authors: Juliastuti Sri Rachmania , Hendrianie Nuniek , Dian Pawitra Yumna , Raditya Putra Irham
Published: March 2018

Waste of Phosphoric acid industry, which called phosphogypsum consists of 65% gypsum, 25% water and 10% impurities. Phosphogypsum can only be used up to 15% and the rest is thrown away. The objective purpose of this study is to reduce the content of P2O5 and F using best variable CaO and stirring during coagulation process, flocculation and sedimentation. The method of this experiment is conducted by using the ratio of phosphogypsum and variable distilled water 1:1, 1:2 and 1:3, and then put it into a jar test using the variable stirring of 100 and 150 rpm. Then 11, 12 and 13 gram CaO and 50 ml distilled water is added as variables for coagulation – flocculation process. pH is kept at 6 by adding 4% NaOH. Polyalumunium chloride (PAC) 0.1% as much as 1.75 mg/l is added into the mixture and stirred at 30 rpm for 20 minutes. The separation of P2O5 and F, is done by the sedimentation process. These experimental results show that variable 1:2 (w/v), 12 gram CaO and 150 rpm stirring able to reduce fluoride and P2O5 up to 98.5% and 50% from phospogypsum.
Preliminary Evaluation of Potassium Extraction from Bamboo Ash
Authors: Samadhi Tjokorde W. , Narcia Febrizca , Amril Hendro
Published: March 2018

Bamboo is a potentially economical fuel crop that has not been utilized at a substantial extent for energy generation in Indonesia. As a thermal conversion waste, bamboo ash is particularly interesting due to its high potassium content. This paper discusses the determination of several key parameters of a simple batchwise extraction process to recover potassium in the form of weak solution from bamboo ash. To produce the ash, black bamboo (Gigantochloa atroviolaceae) is charred in a fixed bed combustor. The bamboo char is ground and ashed at 500 °C in an electric furnace. The ash yield is 3.3 %-mass relative to as-received ash, with an ash K2O content of 12.9 %-mass. The ash is ground until passing 100-mesh standard sieve, and extracted by deionized water on a 2-stage laboratory-scale batchwise extractor battery. Process variables include extractror battery configuration (counter-current and co-current), temperature (nominal setting at 45-80 °C), and contact period of 1-6 hours. The concentration of extracted K2O increases asymptotically with temperature and contact time. Counter-current extraction yields more than twice the extract K2O concentration compared to cross-current extraction. The optimum conditions for the counter-current extraction is identified as a temperature of 78 °C and contact time of 4 hours, resulting in a 0.70 %-mass K2O solution concentration. Spot sampling of commercial liquid fertilizer products in Indonesia indicates an equivalent K2O content of 0.08-13.6 %-mass, suggesting the potential of the bamboo ash extract as an intermediate for fertilizer product.
Bioleaching of trace metals from coal ash using local isolate from coal ash ponds
Authors: Pangayao Denvert , Gallardo Susan , Promentilla Michael Angelo , van Hullebusch Eric
Published: March 2018

Bioleaching of chromium, copper, manganese and zinc from coal ash were investigated using isolates from coal ash ponds particularly Psuedomonas spp. Six (6) different coal ash ponds were examined however, after initial screening Psuedomonas spp. were only present in three (3) coal ash ponds. Among the three coal ash ponds, results showed that eight (8) putative Pseudomonas spp. isolates were present that were identified using the Polymerase Chain Reaction (PCR). Using the eight putative Pseudomonas spp. for bioleaching at optimum conditions and 15 days, the pH value ranges from 8.26 to 8.84 which was basic in nature. Moreover, the maximum metal leached were 8.04% Cr, 12.05% Cu, 4.34% Mn and 10.63% Zn.
Synthesis of Green Diesel From Waste Cooking Oil Through Hydrodeoxygenation Technology With NiMo/γ-Al2O3 Catalysts
Authors: Heriyanto Heri , Murti Sumbogo SD , Heriyanti Septina Is , Sholehah Inayatu , Rahmawati Ayi
Published: March 2018

Hydrodeoxygenation (HDO) of waste cooking oil (WCO) and trapped grease over sulfide catalysts was examined to produce high quality transportation fuel from low-grade resources. The hydrodeoxygenation of waste cooking oils was carried out in a high pressure of 30 and 60 bar and high temperature of 300 – 400 °C in a batch reactor autoclave. NiMo/γ-Al2O3 catalyst was prepared and for the first time tested in hydroprocessing of waste cooking oil. The content of NiMo/γ-Al2O3 in each catalyst was about wCo 5 wt.%. A maximum of 77,97 % green diesel yield was achieved at nearly complete conversion of waste cooking oil using NiMo/γ-Al2O3 at temperature of 400°C, pressure 60 bar and 4 hours of reaction time. The oxygen content was decreased from 14,25 wt.% to 13,35 wt.%, at temperature of 400°C, pressure of 30 bar and 1 hour of reaction time. The Hydrodeoxygenation process was much influenced by temperature, pressure, and time.
The Relative Humidity Effect Of The Reactants Flows Into The Cell To Increase PEM Fuel Cell Performance
Authors: Mulyazmi  , Daud W.R W , Octavia Silvi , Ulfah Maria
Published: March 2018

Design of the Proton Exchange Membrane (PEM) fuel cell system is still developed and improved to achieve performance and efficiency optimal. Improvement of PEM fuel cell performance can be achieved by knowing the effect of system parameters based on thermodynamics on voltage and current density. Many parameters affect the performance of PEM fuel cell, one of which is the relative humidity of the reactants that flow in on the anode and cathode sides. The results of this study show that the increase in relative humidity value on the cathode side (RHC) causes a significant increase in current density value when compared to the increase of relative humidity value on the anode side (RHA). The performance of single cells with high values is found in RHC is from 70% to 90%. The maximum current density generated at RHA is 70% and RHC is 90% with PEM operating temperature of 363 K and pressure of 1 atm
The Comparison of Different Nutrient Sources in Development of Aerobic Granular Sludge
Authors: Choerudin C. , Harimawan Ardiyan , Setiadi Tjandra
Published: March 2018

Aerobic granular sludge (AGS) as recent biological wastewater treatment has been developed in a modified sequencing batch reactor (SBR) using real textile wastewater. This experiment focused on comparing the effects of different nutrient sources, i.e. fine chemicals and fertilizer, on the characteristics of the AGS. The development of AGS conducted in a reactor that called as aerobic up-flow fluidized bed (AUFB) reactor. AUFB reactor allows the three-steps SBR operation namely filling-and-discharging, reaction, and settling. The developed AGS was characterized through some parameters i.e. physical characteristics (morphology, size distribution, settling velocity, specific gravity), granulation profile (MLSS and SVI), and removal performances (removal of COD and colour). The results showed that the developed AGS has a slight morphological difference as the effect of each nutrient source. Interestingly, metal ions contained in the nutrient sources affect the granulation profile and removal performances. Higher metal ions in the sources tent towards better profile (higher MLSS and lower SVI) but decreased removal performance (lower colour removal). In conclusions, this experiment suggests that the use of fertilizers as the nutrient source in developing AGS is comparable to the use of fine chemicals.
High Selectivity of Alkanes Production by Calcium Basic Soap Thermal Decarboxylation
Authors: Neonufa Godlief F. , Pratiwi Meiti , Soerawidjaja Tatang H. , Prakoso Tirto
Published: March 2018

Renewable fuel production from vegetable oil and fat or its fatty acids by direct decarboxylation has been widely reported. An innovative approach to produce drop-in fuel via thermal catalytic decarboxylation of basic soap derived from palm stearin reported in this research. The catalytic effect of the calcium and magnesium metals in the basic soap and its decarboxylation on drop-in fuel yield and product distribution was studied. The catalytic effect was tested in the temperature range up to 370°C and atmospheric pressure for 5 hours in a batch reactor. It has been proved that the calcium basic soap decarboxylation, effectively produce the drop-in fuel in carbon ranges C8 – C20, in which more than 78% selectivity toward alkane. Whereas, only 70% selectivity toward alkane has been resulted from the magnesium basic soap decarboxylation.
Characteristics of Nanoparticles in Drinking Water Treatment using Biological Activated Carbon
Authors: Desmiarti Reni , Morishita Yoji , Fujisawa Tomonari , Ishiguro Yasushi , Yamada Toshiro , Li Fusheng
Published: March 2018

Characteristics of nanoparticles in drinking water treatment were performed using five types of biological activated carbon (BAC) columns (BAC1-BAC5) in continuous flow experiments. The BAC was created by covering granular activated carbon (GAC) with attached microorganisms from water samples taken from the Nagara River in Japan. The total running time was about 2000 h. The characteristics of the nanoparticles were investigated based on size distribution and volume distribution measured by Zetasizer Nano. Total dissolved organic carbon (DOC) and ultraviolet absorbance at 260 nm (UV260) were also studied. The important results in this study were that the detached nanoparticles in the effluent were within the size distribution ranges of 0.26~5.62 nm, 0.62~3.62 nm, 0.62~3.12 nm, 0.62~4.19 nm, and 0.62~6.50 for BAC 1, 2, 3, 4 and 5, respectively. The profile of peak size and peak number along the bed depth of the BAC columns was evaluated for better understanding the characteristics of the nanoparticles. This result is very important for improving drinking water treatment using granular activated carbon to remove microorganisms.
Modelling Sulfonation Kinetics On The Sodium Lignosulphonate Synthesis From Black Liquor
Authors: Hapsoro Aruno Aji , Pramudono Bambang , Priyanto Slamet
Published: March 2018

Surfactant is a compound that has the ability to lower the interfacial tension between the face of two phases (liquid). The need of surfactant has increased along with the development of the industrial sector. One example is sodium lignosulfonat (SLS) which is useful to improve oil acquisition in its application for EOR (Enhanced Oil Recovery). SLS is a result of the reaction between lignin, NaHSO3 (bisulfite) and sodium hydroxide as catalyst. The purpose of this research is to determining the reaction mechanism and determining the value of the reaction rate constant (k). The sulphonation kinetics of lignin was carried out in various temperature (50, 60, 70, 80, and 90°C). From this research obtained a positive (linear) response between sulfonation temperature against reaction rate constants. The lowest k values obtained k50 = 2,05 x 10-4 minute-1 and the highest one is k90= 3,35 x 10-4. From graphycally calculation obtained the value of A is 0,015 and the energy activation (Ea) is-11,708 kJ/mol with R2 = 95,69%. The correlation of the temperature influence to the constant of reaction rate espressed in arhenius equation as follows : k = 0,015 exp (-1408,3/T)
Production of Biodiesel from Mixed Waste Cooking and Castor Oil
Authors: Hadiyanto Hadiyanto , Yuliandaru Inaya , Hapsari Rafidha
Published: March 2018

Due to increasing population growth, the consumption and needs of energy increase significantly. This leads Indonesia government to search alternative energy to cover the lacks of fossil energy reserves. Biodiesel is one of the prospective alternative energy which are renewable and environmental friendly. A common problem in large-scale biodiesel production is the sustainability of feedstock and the biodiesel stability. Therefore, the purpose of this study was to evaluate the production of biodiesel from two oil sources i.e. waste cooking oil and castor oil. This study examined the effect of mixed oil ratio on yield, biodiesel characteristics and stability. The physical properties included kinematic viscosity, acid number, saponification number, iodine number and cetane number have been evaluated as function of oil ratio. Yield of biodiesel was obtained at 35.07%, 99.2% and 83.69% for jatropha:castor oil ratio of 1: 0, 1: 2 and 2: 1, respectively. Most of these characteristics showed an increase by increasing the oil ratio. The result concluded that at the ratio of 1:1(v/v) was the best characteristic and stability.
Non-invasive Detection of Human Body Liquor Intake Based on Optical Biosensor
Authors: Abaoag Christian Jhoart , Alforque Ralph , Ordoño John Benedict , Quinto Edna
Published: March 2018

Alcohol-related incidents are increasing despite the implementation of RA 10586, the Anti-Drunk or Drugged Driving Act of 2013. Conventionally, blood alcohol content (BAC) is tested by gas chromatography or breathalyzers. This work aims to design and fabricate a paper-strip based sensor for the detection of alcohol using saliva as biomedium. The sensor will act as an alternative alcohol detection platform, which will provide low cost analysis of BAC. Different tests were undergone using p-nitrophenol, PNP, as recognition element, which include stability, repeatability, and sensitivity. In order to establish the change of PNP in the presence of alcohol, a UV-Vis spectrophotometer was used. For stability and repeatability, an RSD of 1.24% and 4.61% were obtained, respectively. Furthermore, the sensitivity to alcohol concentration was found to have an R2 value equal to 0.987. For the paper-strip application, 10 mm x 60 mm optical sensing membrane (OSM) with immobilized PNP was prepared. It is analysed through the use of digital image captured by a smartphone camera. The RGB values are then measured using the ImageJ software application. The stability, repeatability, and sensitivity of biosensor are 1.85% RSD, 2.23% RSD, and 0.9731 coefficient of linearity, respectively. This method is a promising alternative to breathalyzer.
Comparison Drying Behavior of Seaweed in Solar, Sun and Oven Tray Dryers
Authors: Suherman Suherman , Djaeni Moh. , Kumoro Andri C. , Prabowo Rizky A. , Rahayu Sri , Khasanah Sufrotun
Published: March 2018

The main objective of this study is to analyze and compare the drying behavior of seawage experimentally in solar dryer, sun dryer and oven dryer. Seaweeds with moisture content of 70% have been cleansed of impurities attached and washed with fresh water. The solar dryer tool is made of glass and iron shaped dryer and box, where the solar collector is made of black painted iron plate. The results showed that the air temperature in solar dyrer was higher than the ambient. The air humidity relative in the solar dryer is lower than the ambient. Drying seaweed by solar dryer method can dry the material up to 12.2% water content within 16 hours, and faster than sun dryer method. Energy utilization per kg of material for solar dryer, sun dryer and oven dryer is 1493 kJ / kg, 1338 kJ / kg, and 1620 kJ / kg, respectively. The quality of the product by the solar dryer method produces the best dried seaweed products in terms of color, aroma and contaminants in the product
Preparation of Graphene Oxide Sand Composites as Super Adsorbent for Water Purification Application
Authors: Andrijanto Eko , Subiyanto Gatot , Marlina Nina , Citra Hanifa , Lintang Cahya
Published: March 2018

This paper describes a method to synthesize a graphene oxide sand composites (GSC) as filter media (absorbent) for water purification. Graphene oxides is synthesized from graphite using modification of Hummer's method. The graphene oxide sand composites is prepared through solution method at 100 °C. The graphene oxide is analyzed using XRD, FTIR to confirm its formation. The FTIR spectrum and XRD diffraction pattern confirmed that the graphene oxide synthesized by this method is able to convert graphite into graphene oxide. Performance tests were conducted using a column to purify contaminated water which was mimicked using dyes such as rhodamine B, methylene blue and methyl orange.The initial concentration for all dyes were set for 5, 10, 25, 50 and 100 ppm. The color removal for methylene blue was 100% at all concentrations. However, for the rhodamine B and methyl orange, the color removal achieved 100% for the first three concentration 5, 10 and 25 ppm. The higher concentration of 50 and 100 ppm, the removal were slightly reduced. For the 50 ppm, the color removal of rhodamine B was 98% and for methyl orange 87% respectively. At 100 ppm, the color removal for rhodamine B drops to 92% and for the methyl orange was only 77% respectively. The GSC was very effective to remove methylene blue dyes at any concentration followed by rhodamine B and methyl orange. This GSC composite material is potential to be applied for water purification.
Characterization Nanofillers from Agriculture Waste for Polymer Nanocomposites Reinforcement
Authors: Arifin Bastian , Aprilia Sri , Nurul Alam Pocut , Mulana Farid , Amin Amri , Anaska Dilla Mars , Eka Putri Dwita
Published: March 2018

The current development of the packaging industry is increasing as well as the dependence of non-renewable oil-based materials encouraging researchers to look for alternative polymeric strengthening materials from biomass. Especially used from agricultural waste because it is cheap and widely available in nature and it can be renewed. In this study, agriculture waste used were rice husk and rice husks ash that prepared as organic nanofillers for the development of polymer nanocomposites. XRF analysis showed that rice husk ash has the highest silica (SiO2) content of 89. 835%, while rice husk has SiO2 contents of 82.540%. From XRD analysis on 2 theta there is a crystalline silica region at 22° and this analysis shows the sample is amorphous. FTIR analysis showed Si-H at peak 2339 cm−1 in rice husk and 2129 cm−1 for rice husk ash.
The Effect of Metal Loading and Alkaline Treatment on The Zeolites Toward Catalytic Pyrolysis of γ-Valerolactone
Authors: Rasrendra Carolus Borromeus , Luthfi Muhammad , Asriani Vika , Rizkiana Jenny , Kariem Muhammad A , Sasongko Dwiwahju
Published: March 2018

γ-Valerolactone (GVL) is a glucose derivatives and its utilization as organic solvent has been developed to extract lignin from biomass. Both GVL and lignin can be used for producing aromatic chemicals (Bezene, Toluene, Xylene – BTX) via catalytic pyrolysis. We present a study focused on the catalyst modification of the zeolites to produce BTX from GVL. The catalysts were modified using wet impregnation method and alkaline treatment using NaOH solution. The addition of metal oxides were examined. Catalyst performance test were carried out in a fixed bed reactor. The feed was flowed at flowrate of 0.2 ml/min in 50 ml/min N2. The operating temperature was maintained at 500°C with catalyst-to-GVL ratio of 1:1.5. The results showed that adition of Fe-metal improves zeolites activity compared with parent zeolites. Alkaline treatment had negative impact on HZSM-5 activity because of the change of silica-alumina-ratio (SAR) and average pore diameter.
A Review of Bio-lubricant Production from Vegetable Oils Using Esterification Transesterification Process
Authors: Annisa Arianti N. , Widayat Widayat
Published: March 2018

Since long time ago, petroleum oil has been used as a lubricant in motor vehicles. But, the uses of lubricants petroleum can pollute the environment and disrupt marine ecosystems and terrestrial. On the other hand, the use of lubricants in the world in 2008 reached 46 million kiloliters/year and increased by 2% every year. The future prospect the uses of lubricant petroleum on the vehicle’s engine is predicted to have a bad prospect. Thus began research to identify suitable materials to replace petroleum based lubricants. It can produce from vegetable oils and animals oils by chemical modification. But, bio-lubricant properties are easily damaged so we need more research to improve the shelf life of the bio-lubricant. The research must be done to improve the characteristics by adding a bio-lubricant additive.
Fuzzy-GMC Control of Gas-Phase Propylene Copolymerization in Fluidized Bed Reactor
Authors: Salahuddin Nazratul Fareha , Shamiri Ahmad , Hussain Mohd Azlan , Mostoufi Navid
Published: March 2018

A modified two-phase model for gas phase propylene and ethylene copolymerization was chosen to represent the process in a fluidized bed reactor. This model considered the entrainment of solid particles in the reactor, as a modification to the original two-phase model assumptions. The non-linearity of this process makes it difficult to control just by using conventional controller such as PID. A hybrid control strategy (a simple designed fuzzy logic controller (FLC) integrated with generic model control (GMC)) is designed to control the temperature of the reactor. This advanced control system was compared with the GMC and conventional PID controller. The simulation results showed that the hybrid controller (Fuzzy-GMC) performed better than both GMC and PID in terms of both servo and regulatory control.
Hydrophylicity Enhancement of Modified Cellulose Acetate Membrane to Improve the Membrane Performance in Produced Water Treatment
Authors: Kusworo Tutuk Djoko , Soetrisnanto Danny , Santoso Cynthia , Payanti Tyas Dwi , Utomo Dani Puji
Published: March 2018

Produced water is a wastewater generated from petroleum industry with high concentration of pollutants such as Total Dissolved Solid, Organic content, and Oil and grease. Membrane technology has been currently applied for produced water treatment due to its efficiency, compact, mild and clean process. The main problem of produced water using membrane is fouling on the membrane surface which causes on low permeate productivity. This paper is majority focused on the improvement of anti-fouling performance through several modifications to increase CA membrane hydrophilicity. The membrane was prepared by formulating the dope solution consists of 18 wt-% CA polymer, acetone, and PEG additive (3 wt-%, 5 wt-%, and 7 wt-%). The membranes are casted using NIPS method and being irradiated under UV light exposure. The SEM images show that parepared membrane has asymmetric structure consist of dense layer, intermediete layer, and finger-like support layer. The filtration test shows that PEG addition increase the membrane hydrophilicity and the permeate flux increases. UV light exposure on the membrane improves the membrane stability and hydrophilicity. The imrpovement of membrane anti-fouling performance is essential to achieve the higher productivity without lowering its pollutants rejection.
Development of Nano-hybrid Cellulose Acetate/TiO2 Membrane for Eugenol Purification from Crude Clove Leaf Oil
Authors: Kusworo Tutuk Djoko , Soetrisnanto Danny , Utomo Dani Puji
Published: March 2018

Chemical separation and purification are the important part of the chemical industry which consumes up to 70% energy cost. The separation technology such as distillation and absorption are well known in essential oil purification. The purification of clove leaf oil needs an attention because the current technology still consumes high energy and produces chemical wastes. The employment of membrane separation for clove leaf purification is a novel concept that needs many improvements. The main problem of polymeric membrane utilization is eugenol ability to dissolve the polymer membrane. Cellulose acetate is one of membrane polymers that is insoluble in eugenol. This paper reveals the performance of nanohybrid CA/TiO2 membrane for eugenol purification. The stability of produced membrane as an organic solvent nanofiltration (OSN) is evaluated in this study. The SEM image result shows that fabricated membrane has an asymmetric structure of membrane sub-layer. The different nano-particles loading shows the variation of permeate fluxes, the increase of nano-particles in polymer blend tends to increase the permeability. Thus, this study provides an overview of the potential CA/TiO2 for OSN development by incorporating inorganic nano-particles in membrane polymers for eugenol purification that can be integrated in upstream separation process.
Physical and mechanical properties of membrane polyvinilidene flouride with the addition of silver nitrate
Authors: Mataram Agung , Rizal S. , Pujiono Estu
Published: March 2018

The membrane is a layer formed from fine fibers are used as a filter. In this research, measured the tensile strength and pore size of the membrane that is made in three variations of a specimen with a mixed composition of different Polyvinilidene Fluoride 17.5%, 20%, 22.5%., membrane made using Polyvinilidene Fluoride polimer granules andN,N-Dimethylformamideas solvent and silver nitrate. Membrane molded into standardized test specimens and tested with a device Adhesion Tearring Strength Tester. The results show an increase in the value of the tensile test of 404.8356 KPa to the composition of 17.5%, 507.3598 KPa for composition of 20% and 603.7218 KPa to a composition of 22.5%. For testing the microstructure using a Scanning Electron Microscopy with the resulting increase in pore diameter, for the range of 558.4 nm-781.8 nm are void to the composition of 17.5%, range 670.1 nm - 781.8 nm without voids for the composition of 20% and 1.117 μm-1.228μm without voids on a composition of 22.5
Preparation and Characterization of Porous Ceramic Membranes for Micro-Filtration from Clay/CuZn Using Extrusion Methods
Authors: Amin Muh , Subri Muhammad
Published: March 2018

In this study, fabrication and characterization of ceramic membranes preparation was carried out. Porous ceramic membranes were fabricated by extrusion process from different percentage composition of CuZn on (80 wt% Clay, 10 wt% TiO2, 5 wt% Carbon and 5 wt% PVA). The fabricated membranes were sintered at 900°C for 1 hour in an electrical box furnace with heating rate 1oC/min and holding time for 1 hour. Apparent density and porosity were determined by standar methods for ceramic materials. Phase composition of the ceramic support was established by X-Ray Diffraction analysis. SEM studies of the membranes added at different CuZn were carried out.
Structural design of soldering station chain conveyor working positions
Authors: Blatnický Miroslav , Dižo Ján , Blatnická Mária
Published: March 2018

The paper deals with design of the support and guide of the conveyor chain links, the individual working positions of the handling mechanism for the conveyor line, i.e. positions of manual loading of components on the line and automatic soldering of the component. The entire design will serve as an input for the dimensional calculation of the propulsion engine of the proposed conveyor line in order to enable the production of a real functional prototype.
Wear evaluation of elements of V-belt transmission with the application of optical microscope
Authors: Krawiec Piotr , Waluś Konrad , Warguła Łukasz , Adamiec Jarosław
Published: March 2018

The paper presents the analysis of reasons, form and wear of elements of V-belt transmission. Syndromes of loss of driving properties for chosen wheels and V-belts are specified. Methodology of failure evaluation of wheels and V-belts with the application of optical microscope is proposed. The applied measuring set allows for universal analysis of the measurement results. Operation principle of this device and its measuring and analysing abilities are shown. Failures of chosen V-belts and the influence of these failures on accuracy of kinematic features of chosen driving units are evaluated.
The material parameters for computational modeling of long-fibre composites with textile
Authors: Krmela Jan , Krmelová Vladimíra
Published: March 2018

In this contribution, the composites with textile fibre (cord) and an elastomer matrix are studied based on computational modeling of car tires in combination with experiments. These composite are applied in tire casings for cars, conveyor belts etc. The aim of this research work of authors is creation of computational models namely for stress-strain analyses of selected parts of radial tire casing. The typically passenger car radial tire casing consists of one or two polyester plies in tire carcass and two steel-cord belts and one polyamide 66 cap ply below tread. The finite element method using the program system ANSYS is applied to the computational modeling. For the determination of the material parameters of elastomer and textile cords as input data to the computational models, it was necessary to perform tests as statically tensile tests. Also the experiments of composites as tests of low cyclic loading of composites are needed for verification analyses between computational results and experimental data. For computational modeling, the modulus of elasticity and Poisson ratio are used as material input parameters of textile reinforcements. The results from the computational modeling and selected results from the tests are presented in this contribution.
Computer simulation of the load test of an extrusion blow moulded product
Authors: Modławski Michał , Nabiałek Jacek , Jaruga Tomasz
Published: March 2018

The results of compression "top load" test of an extrusion blow moulded container, performed in ANSYS Mechanical software, were presented. The non-uniform wall thickness of the blown product was considered because the thickness distribution was the result of the first step of the simulation in ANSYS Polyflow - the simulation of the product manufacturing by extrusion blow moulding. The hydrostatic pressure factor was taken into account during the "top load" simulation, because such a test is usually done for filled products. It was found that the biggest stress values occur around the inlet as well as in the side walls of the container.