bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of pH on Physicochemical Properties of Cassava Starch Modification Using Ozone
Authors: Pudjihastuti Isti , Handayani Noer , Sumardiono Siswo
Published: March 2018

Nowadays, starch modification is carried out in order to change the native properties into the better ones, such as high stability, brightness, and better texture. The objectives of this study are to investigate the effect of pH on carboxyl content, swelling power, and water solubility of starch. This research was divided into two main stages, i.e. starch modification by ozone oxidation and analysis. The physicochemical properties of modified cassava starch were investigated under various reaction pH of 7-10 and the reaction time between 0-240 minutes. Reaction condition at pH 10 provided the higher value of carboxyl content and water solubility, but the lower of swelling power. This increase in solubility indicates that the modified oxidation starch readily dissolves in water, due to its small size granules and high amylose content. The significant changes of both parameters were achieved in the first 120 minutes of ozone reaction times. The graphic pattern of water solubility was in contrast with swelling power.
Effect of Promoter Concentration on CO2 Separation Using K2CO3 With Reactive Absorption Method in Reactor Packed Column
Authors: Monde Junety , Widjaja Tri , Altway Ali
Published: March 2018

The presence of carbon dioxide (CO2) in the gas is not expected because CO2 can reduce heating value and CO2 is the major emission contributor into the atmosphere. Various separation technologies can be used to reduce CO2 content and improve quality of gas. Chemical or reactive absorption is most widely used because it provides higher removal rate. This paper will study the effect of the addition di ethanolamine (DEA) concentration into aqueous 30wt.% potassium carbonate(K2CO3) with reactive absorption method in a reactor packed column at temperature from 40°C to 80°C, DEA concentration range of (1% - 3%) and absorbent flow rate (0.5, 0.75 and 1) L. min1. Contacting the gas and absorbent are countercurrent flow in packed column with 1.5 m high and 50 mm in diameter. The absorption column was randomly packed with a packing material raschig rings 5 mm in diameter. The CO2 loading in the liquid samples was determined by titration. It is found that the best result of CO2 loading is 0.065594 mole/mole K2CO3 and CO2 removal 28%. The result show that the loading capacity (mole CO2/mole K2CO3) and CO2 removal increased with the increase of DEA concentration.
Mathematical Modeling of the Drying Kinetics of Thinly-Sliced Saba (Musa Balbasiana) Using Hot-Air Dryer
Authors: Pestaño Lola Domnina B. , Bautista John Paul T. , Leguiab Reizl JR. H. , Puri Sean Danielle D.
Published: March 2018

Banana is one of the top produced crops in the Philippines, and among its cultivars is the Musa balbasiana, commonly known as saba. Due to its high moisture content, saba is perishable and one of the methods to increase its shelf-life is drying. The shelf life of saba can be extended up to six months when dried to 12% moisture content. The research focuses on the effect of banana maturity and choses a mathematical model which will best fit its drying kinetics. The banana samples, the unripe and ripe saba, were bone-dried without pre-treatment using a hot-air tray drier. To produce repeatable data, three trials were done for temperatures 40°C, 50°C and 60°C. Among the three mathematical models used in the study, the treated data for both unripe and ripe saba best fit the Laplace Transform Model. Using Lagrange interpolation, the time per trial was computed; unripe saba dried at 50°C achieved the ideal moisture content in an average time of 87.5574 minutes for the three trials while that of ripe saba dried at 40°C achieved the same moisture content in an average time of 88.8619 minutes for the three trials. With the increase in temperature, the discoloration decreased indicating an enzymatic character ofbrowning.
Carrageenan Extracted from Eucheuma cottonii Through Variant of Drying Time
Authors: Pralisa Putri Novy , Susandy Sanjaya Ari , Kartika Sari Neli , Puspita Sari Reni , Bindar Yazid
Published: March 2018

Carrageenan is a derivative product of seaweed that used in various fields such as pharmacy, food and cosmetics. One of the most widely used carrageenan from seaweed was Eucheuma cottonii sp. The research was conduct to determine the effect of post-harvest seaweed pre-treatment on yields of Carrageenan. The first pre-treatment done by using the fresh seaweed that has been washed clean then directly dried. The second pre-treatment, washed seaweed soaked with clean water for seven days and then dried with a dryer. Drying time for the first and second pre-treatments is varied, then dried seaweed extracted with water to produce carrageenan. The analyses performed were moisture content of seaweed and yields of Carrageenan. The results of the research found that the initial moisture content of seaweed on the second pre-treatment was greater than the first pre-treatment. The variation of drying time on the first pre-treatment did not affect significantly on the yields, but in the second pre-treatment, yield of carageenan increased with accumulation drying time.
Study of Acid Hydrolysis on Organic Waste: Understanding The Effect of Delignification and Particle Size
Authors: Anwar Nadiem , Mukhaimin Iman , Harsanti Mining , Romli Ate
Published: March 2018

Organic wastes from Swiettenia marcophylla L, Artocarpus heterophyllus L, Mangifera indica L, and Annona muricata L were prepared by grinding into 0.1875, 0.3750, 0.7500 mm of particle size and delignified by 2% NaOH at 80°C for 90 minutes. Acid dilution hydrolysis process with H2SO4 1% was performed at 150°C for 120 minutes in a closed reactor. The effect of particle size and delignification on and reducing sugar concentration were investigated. The result showed (1) leaves that can be used as raw material to produce hydrogen should have 38–49% cellulose and hemicellulose. (2) Reducing sugar concentration increased with particle size reduction and delignification. (3) the best result with the highest reducing sugar concentration was achieved by 0.1875 mm particle size with delignification on Annona muricata L.
Evaluation of Ankistrodesmus falcatus for Bicarbonate-Based Integrated Carbon Capture System (BICCAPS)
Authors: Beltran Arnel B. , Gravador Daniel C. , Ty Bea Lutchi O. , Wu Joceleen Michelle O.
Published: March 2018

This study evaluates the performance of alkaliphilic microalgae Ankistrodesmus falcatus in the Bicarbonate-based Integrated Carbon Capture and Algae Production System (BICCAPS). The system utilized bicarbonate as carbon source for microalgae production. BICCAPS parameters such as pH, algal biomass productivity and CO2 utilization (inorganic carbon conversion, Ci) were observed at different sodium bicarbonate (NaHCO3) loading concentration and type of culture media. The highest productivity was observed at 10 g/L of NaHCO3 loading in BRSP medium at 3.5539 mg/L/day. This value is 30% lower compared to the control experiment (continuously aerated bioreactor). The Ci values of the different system ranges from 1.17 x 10-4 to 1.51 x 10-4 moles/L/day. Both the pH of the BRSP and NPK media at 10 g/L and 30g/L loading of NaHCO3 increased through time. The result shows that A. falcatus has a potential in BICCAPS utilization.
Temperature, Solid Loading and Time Effects on Recovery of Sugar from OPEFB
Authors: Meilany Diah , Kresnowati MTAP , Setiadi Tjandra
Published: March 2018

Biorefinery industry used lignocellulosic biomass as the raw material. Oil Palm Empty Fruit Bunch (OPEFB) is one of Indonesian potential lignocellulosic biomass, which consists of hemicellulose with xylan as the main component. Xylitol production via fermentation could use this xylan since it can be converted into xylose. However, the structure of OPEFB is such that hemicellulose is protected in a way that will hinder hydrolysis enzyme to access it. Considering that hemicellulose is more susceptible to heat than cellulose, a hydrothermal process was applied to pre-treat OPEFB before it was hydrolyzed enzymatically. The aim of the research is to map the effect of temperature, solid loading and time of pre-treatment process to obtain and recover as much as possible accessible hemicellulose from OPEFB. The results showed that temperature gave more significant effect than time and solid loading for glucose recovery of OPEFB residues. While xylose recovery varies greatly with temperature, but solid loading and time gave less significant effect.
Data Reconciliation and Gross Error Detection for Troubleshooting of Ammonia Reactor
Authors: Adhi Tri Partono , Saputro Untoro Eko
Published: March 2018

Data reconciliation (DR) and gross error detection are two common tools used in industry to provide accurate and reliable data, which is useful to analyse plant performance and basis for troubleshooting. DR techniques improve the accuracy of measurements by using redundancies in material and energy balances. This provides reliable information that could help decision making regarding plant operation, which potentially leads to financial benefit. This paper presents the utilization of plant data to perform troubleshooting of ammonia reactor, in particular the profile of catalyst activity. Bad plant data are collected and then analysed using DR to produces reconciled data, which could be used to detect and identify the gross error measurements. The input data for DR and gross error detection were gathered from Aspen HYSYS V8.8 simulations by modelling the single-bed ammonia reactor. The result presents that bad plant data could define actual system condition such as gross error measurements in normal condition or catalyst activity problem. Both conditions are modelled by DR to indicate actual system condition using statistical analysis and to perform troubleshooting. Appropriate troubleshooting could save time and provide financial benefits by avoiding wrong accusation of system problem, specifically in ammonia reactor evaluated in this paper.
The Effect of C/N Ratio and Type of Microbes Sludge to Biogas Production: Combination of Tapioca Industrial Wastewater and Tofu Industrial Wastewater
Authors: Hadiyarto Agus , Soetrisnanto Danny , Miftahul Huda Faishal , Amelia Iswara Nimas
Published: March 2018

Biogas will be produced from a single organic substrate and controlled the ratio of carbon nitrogen by added inorganic nitrogen substances. The study has been tried to combine substrates from industrial tapioca industrial wastewater with tofu industrial wastewater. The experiments were carried out in batch anaerobic digesters with a C/N ratio range of 20 - 30 and variation of microbial sludge from cow rumen, anaerobic sludge of tofu wastewater treatment plant (WWTP) and anaerobic sludge of tapioca WWTP. The ratio of C/N in the range of 20-30 didn’t significant effect on the volume of biogas production. The microbial from cow rumen gives the best biogas production performance. Biogas yield is 2,199 liter per kg COD.
Drinking Water Treatment by Inductively Coupled Plasma System to Remove of Microorganisms in River Water
Authors: Desmiarti Reni , Hazmi Ariadi , Emeraldi Primas , Martynis Munas , Trianda Yenni , Sutopo Ulung M.
Published: March 2018

Inductively coupled plasma system was used in drinking water treatment system to kill the microorganisms in water such as total coliforms (TC), fecal coliforms (FC) and other coliforms (OC) from river water. The aim of this study was to investigate the effect of flowrate on removal efficiency (RE), death rate, and death yield and energy consumption of bacteria's. The frequency of the system was set at 4.6 MHz. The results show that the removal efficiencies and death rate of TC, FC and OC decreased with increasing flowrate. Compared to FC, the first-order reactions of TC and OC were lower in the following order: FC > OC > TC. The death yield of TC and OC significantly increased when the removal efficiency increased. The electromagnetic flux varied from 19.44 to 20.55 W/cm2 and the energy consumption was 0.26, 0.32, and 0.67 with flow rate at 20, 10 and 5 mL/minute, respectively. These results are very necessary to improve drinking water treatment.
Optimized Ultrasound-Assisted Oxidative Desulfurization Process of Simulated Fuels over Activated Carbon-Supported Phosphotungstic Acid
Authors: Gildo Peniel Jean , Dugos Nathaniel , Roces Susan , Wan Meng-Wei
Published: March 2018

Recent technological advancements respond to the call to minimize/eliminate emissions to the atmosphere. However, on the average, fuel oils which is one of the major raw materials, is found to increase in sulfur concentration due to a phenomenon called thermal maturation. As such, a deeper desulfurization process is needed to obtain low/ultra-low sulfur fuel oils. In the present study, the ultrasound assisted oxidative desulfurization (UAOD) processes using the H2O2 and HPW-AC oxidizing system applied to simulated fuel (~2800 ppm sulfur in the form of dibenzothiophene, benzothiophene, and thiophene dissolved in toluene), were optimized. After the pre-saturation of the HPW-AC with the simulated fuel, H2O2 was added just before the reaction was commenced under ultrasonic irradiation. After the application of both 2k-factorial design of experiment for screening and Face-Centered Design of Experiment for optimization, it was found that 25.52 wt% of H2O2 concentration, 983.9 mg of catalyst dose, 9.52 mL aqueous phase per 10 mL of the organic phase and 76.36 minutes of ultrasonication time would render 94.74% oxidation of the sulfur compounds in the simulated fuel. After the application of the optimized parameters to kerosene and employing a 4-cycle extraction using acetonitrile, 99% of the original sulfur content were removed from the kerosene using the UAOD optimized parameters. The desulfurization process resulted in a low-sulfur kerosene which retained its basic fuel properties such as density, viscosity and calorific value.
Ball-milling effect on Indonesian natural bentonite for manganese removal from acid mine drainage
Authors: Prastistho Widyawanto , Kurniawan Winarto , Hinode Hirofumi
Published: March 2018

The influences of mechanical milling on Indonesian Natural Bentonite (INB) characteristics and manganese (Mn) removal from acid mine drainage (AMD) were investigated. The INB characteristics were observed by scanning electron microscope (SEM), X-ray diffraction (XRD), nitrogen adsorption-desorption for specific surface area (SSA) and microporosity measurement, cation exchange capacity (CEC) and particle size distribution (PSD) analyzer. Four minutes milling with frequency 20 Hz on INB caused morphological change which showed more crumbled and destructed particle, lost the (001) peak but still retained the (100) peak that indicated delamination of montmorillonite mineral without breaking the tetrahedral-octahedral-tetrahedral (T-O-T) structure, rose the CEC from 28.49 meq/100g to 35.51 meq/100g, increase in the SSA from 60.63 m2/g to 104.88 m2/g, significant increase in microporosity which described in the t plots and decrease in the mean particle size distribution peak from 49.28 μm to 38.84 μm. The effect of contact time and effect of adsorbent dosage on Mn sorption was studied. Both unmilled and milled samples reached equilibrium at 24 hours and the pH rose from 4 to 7 in first 30 minutes. The Mn removal percentage increased significantly after milling. Using Langmuir isotherm, the maximum adsorbed metals (qmax) also increased from 0.570 to 4.219 mg/g.
Dynamic Study of Feed-Effluent Heat Exchanger Addition on Double Bed Configuration Ammonia Reactor System within Varied Quenching Ratio
Authors: Adhi Tri Partono , Akbar Ferdyan Ihza
Published: March 2018

Ammonia is one of the most important industrial commodity due to its wide function. Ammonia synthesis reaction is an exotermic reaction. Therefore, Feed-Effluent Heat Exchanger (FEHE) is added to increase thermal efficiency. However, FEHE could lead the process to experience hysteresis phenomenon due to interaction between equipments as one steady state T feed could result several T outlet. Hysteresis phenomenon may result asset losses like explosion, leakage, and loosing material integrity. Double bed reactor configuration allows us to use several operating parameters as variation to overcome hysteresis. In this review, quenching ratio was chosen to be that varied parameter. This study aims to determine how quenching ratio affects hysteresis zone by utilizing Aspen Hysys® V8.8 as simulation tool. Simulation showed that quenching ratio would narrow hysteresis zone yet increased extinction temperature that lower the conversion. Conversion profile showed that 0.2 quenching ratio got the highest conversion for system with bed volume ratio 2:1 while total volume was 30 m3. However, the feed temperature was fallen at hysteresis zone. Dynamic simulation showed that highest conversion feed temperature (10%ΔTf above extinct temperature) was still able to preserve stability with descending temperature approach. Hysteresis itself started to occur at 1.7%ΔTf above extinct temperature
Organic pollutant degradation of tapioca flour industrial waste with photo-fenton reaction
Authors: Sarajar Alin Elita Esther , Ramadhania Refa Putri , Purwanto Purwanto
Published: March 2018

Cassava (Manihot utilissima) is the main raw material of tapioca flour industry. The tapioca industry waste water still contains high enough BOD, COD, and cyanide, above the quality standard of industrial waste water. Photo-Fenton is one of the most effective alternative methods of degrading organic pollutants. This study aims to determine the effect of Photo-Fenton method on the degradation of organic pollutants such as COD and cyanide. For operating conditions of this study use the addition of concentrations of H2O2 and FeSO4.7H2O and different UV light intensity. The analysis of COD concentration using SNI method is spectrophotometric. From the research result, it is found that the concentration of COD and cyanide in tapioca waste can be reduced by using Photo-Fenton method. With initial COD content of 6000 mg/L and cyanide level of 0.67 mg/L. And in the operating conditions of the addition of 5 ml/l of H2O2, Fe2+ 1.25 mg/l, and light intensity of 200 lm, the highest COD and cyanide levels were found to be 900 mg/l for COD and 0.08 mg/l for cyanide. Final levels of COD up to 900 mg/l and cyanide concentrations up to 0.08 mg/l.
Study of Biogas Production from Cassava Industrial Waste by Anaerobic Process
Authors: Budiyono  , D. Primaloka Arindra , Ardhannari Listi , H.A. Matin Hashfi , Sumardiono Siswo
Published: March 2018

Biogas production processes from tapioca wastewater have several problems that cause the biogas production is not optimal, such as pH drop at beginning of the process because the rate of acid formation is too fast and the rate of starch wastewater degradation is too slow. Therefore, to obtain optimal biogas production it is required two-stage reactor. The purposes of this research were to (i) study the influence of one stage fermentation and two stage fermentation on biogas production, (ii) study the effect of buffer Na2CO3 on biogas production, and (iii) study the effect of methanogenic bacteria concentration on biogas production from cassava starch effluent. The first method of our research was hydrolysis process by “Saccharomyces cereviceae” as substrate activator. The second is the arrangement of pH and the last is process of methane production. The results showed that the highest biogas production is achieved at concentration of methanogenic bacteria 20% (v/v) that is equal to 2458 ml. At concentration of 8% (v/v) and 15% (v/v), biogas production was 2105 ml and 2117 ml. The addition of Na2CO3 can extend to 16 days with accumulation of 372 ml. While without the addition of buffer, biogas production period was only 9 days with accumulation of 620 ml. In semi continuous process, the analysis carried out every 3 days. Highest biogas production achieved in the variable addition of yeast with the accumulation 9329 ml. Without yeast, accumulation of biogas was 6831 ml. Yeast is use as substrate activator so it can accelerate the hydrolysis process and increased biogas production. The addition of Na2CO3 is increase the alkalinity so the pH drop did not occur early in the process.
Natural Dye Extraction From Teak Leves (Tectona Grandis) Using Ultrasound Assisted Extraction Method for Dyeing on Cotton Fabric
Authors: Qadariyah Lailatul , Mahfud Mahfud , Sulistiawati Endah , Swastika Prima
Published: March 2018

Synthetic dye waste of textile industry has contaminated the water and aquatic living organism. One of the solution is used teak leaves as the natural dye. Common conventional extraction process is soxhletation which need more time and more solvent. One of extraction method that has been developed is ultrasound assisted extraction (UAE). The objectives of this research were to study the effect of solvent, extraction time, pH, and extraction yield. The conclusion of this research was optimum yield of teak leaves extract about 42,79% at pH 3 and extraction time of 20 minutes with aquadest as the solvent using UAE method. If natural dye of taek leaves was used on cotton, the color will change depend on fixator that was added. In GC-MS analysis, some compound that were detected are decanoic acid methyl ester and methyl tetradecanoate. Both of the compound have chromophore cluster.
Chemical and Spectral Characterization of The Ozonation Products of κ-Carrageenan
Authors: Prasetyaningrum Aji , Jos Bakti , Dharmawan Yudhy , Octaviani Ratih V. , Ratnawati Ratnawati
Published: March 2018

Kappa (κ-) carrageenan oligomers are known to have several biological activities. Recent progress in the development of modified κ-carrageenan has resulted low molecular of κ-carrageenan. Ozone is a powerful oxidant and considered for depolymerization of κ-carrageenan. However, few studies have investigated the changes in κ-carrageenan properties associated with ozone treatment. This study would investigate on the changes in chemical structure after ozonation process. The experiments were carried out in a glass reactor equipped with an ozone bubble diffuser. Ozone with concentration of 80 ± 2 was bubbled into the solution. The ozone treatment was conducted at different times, i.e., 0 (control), 5, 10, 15, and 20 minutes. The experiments were conducted at pH 7 and constant stirring speed (200 rpm). Ozone-treated κ-carrageenan was dried at 60 ºC for 24 h in a forced air oven. The chemical and spectral analyses of κ-carrageenan after ozonation process were carried out using UV-Vis and FT-IR spectroscopy. These changes are seen in the UV spectra as a high intensity of absorbance peak at 290 nm. It is shows that ozonation of κ-carrageenan leads to some chemical changes such as the formation of carbonyl, carboxyl or double bonds.The FT-IR spectra reveals that the chemical structure of degraded κ-carrageenan, in term of sulfate content, is only slightly affected by the ozone treatment.
Hydrothermal Carbonization of Seaweed For Advanced Biochar Production
Authors: Prakoso Tirto , Nurastuti Rima , Hendriansyah Reza , Rizkiana Jenny , Suantika Gede , Guan Guoqing
Published: March 2018

Seaweed such as Eucheuma Cottonii is a potential source of biomaterialIts high moisture content makes it suitable for hydrothermal conversion process since it doesn’t need to utilize dry feedstock. The aim of this study is to convert the biomass of red seaweed Eucheuma Cottonii into alternative fuels and high value biomaterials using hydrothermal process. The hydrothermal process seaweed Eucheuma Cottonii produce two types of products, liquid product and char (solid). This research focus on the char product. The char from hydrothermal process was then activated using the tubular furnace. The yield for activated char is 7.5 % and results of SEM analysis of activated char showed the formation of allotropes carbon include carbon micro spheres, carbon micro fibres and graphene. These structures have encountered application in a wide range of technological fields, such as adsorption, catalysis, hydrogen storage or electronics.
Silicon Conversion From Bamboo Leaf Silica By Magnesiothermic Reduction for Development of Li-ion Baterry Anode
Authors: Silviana Silviana , Bayu Wardhana J.
Published: March 2018

Silicon (Si) is a promising alternative material for the anode Lithium ion Battery (LIB). Si has a large theoretical capacity about 3579 mA hg-1, ten times greater than the commercial graphite anode (372 mA hg-1). Bamboo is a source of organic silica (bio-silica). Most part biogenetic content of SiO2 is obtained in bamboo leaves. This paper aims to investigate the synthesis nano Si from bamboo leaves through magnesiothermic reduction after silica extraction using sol–gel method and to observe nano Si of bamboo leaf as mixed material for lithium ion baterry. Silica and silicon content was determined using XRF. Silica product has 96,3 wt. % yield of extraction from bamboo leaf, while silicon yield was obtained 61.2 wt. %. The XRD pattern revealed that silica and silicon product were amourphous. The extracted silica and silicon from bambo leaf has spherical shape and agglomerated form. As anoda material for LIB, silicon product achieved 0,002 mAh capacity for 22 cycle.
Performance Evaluation of Pneumatic Dryer for Aren (Arenga piñata) Flour
Authors: Suherman Suherman , Hidayati Nur
Published: March 2018

Aren (Arenga pinata) tree is one type of palm plant that produces fruit, sap and starch or flour in the trunk. Industries aren flour usually in small and medium industries is dried by conventional method with dried under the sun. The main constraint is the low drying speed. Therefore, in this study aren flour with a water content of 40% was dried using a pneumatic dryer to moisture content below 15% (wet base). The aim of this research is to analyze the influence of drying air temperature, drying air flow rate and feeding speed to drying speed and energy analysis. Energy analysis was performed to determine the performance of pneumatic dryers. The energy analysis itself is done in the form of energy utilization and energy efficiency. The results show that the increase of dryer temperature from 60 to 100 will increase the utilization of energy from 0.61 to 1.39 J / s, energy efficiency is 33.4-45.1%. the results of a proximate analysis, an ash content of 0.39 grain fiber 0.18 white degree 92.93% which already fulfill SNI standard of Aren flour.
Effect of Impeller Position and Baffle Width on Uniformity of Fe Concentration for Fortification of Baby Instant Porridge
Authors: Santosa Herry , Handayani Noer , Haryani Kristinah , Sitorus Bontor , Mawarni Muhija
Published: March 2018

Iron deficiency (ID) is considered to be the most micro-nutritional problem, and the main cause of anaemia, called Iron Deficiency Anaemia (IDA). Nowadays, iron fortification is the most practical and priority solution for IDA alleviation. For toddler, iron fortification could be performed on complementary food of breast milk, such as instant porridge. Iron fortification was conducted using mixing and agitation method to prepare instant porridge from purple sweet potato flour. The aims of this work were to investigate the effect of impeller position and baffle width on the uniformity of iron concentration. Preparations of purple sweet potato flour and iron fortification were conducted using drying and mixing agitation method, respectively. Two independent variables, i.e. impeller position (1, 1.8, 2.6, 3.2 cm from the bottom of stirred tank) and baffle width (1.1, 1.4, 1.8, 2.3 cm), were used to investigate the uniformity of iron. Iron concentration was determined by atomic absorption spectrophotometer (AAS). The results depict that impeller position 1.8 cm from the bottom of the stirred tank and baffle width 1.1 cm provide a relatively good operating condition to obtain the high level of iron uniformity.
Microwave-assisted Extraction of Natural Dyes from Coleus atropurpureus Leaves: The Effect of Solvent
Authors: Gala Selfina , Sumarno Sumarno , Mahfud Mahfud
Published: March 2018

A microwave-assisted extraction system was used to extract natural dyes from Coleus atropurpureus leaves. The effects of water solvent of the temperature at 100°C and 80°C as well as ethanol solvent 96% were investigated. This is done at the various material to solvent ratio (0.001, 0.0025, 0.005 g/mL) and microwave power (264, 400, 600 watt). The optimal conditions of the extraction were obtained on a water solvent of the temperature at 100°C with material to solvent ratio 0.001 g/mL, irradiation power 400 watt, extraction time 10 min, material size 35-60 mesh, the optimum yield of 44.48%. Identification of groups of pigments contained in the Coleus atropurpureus leaves is known categories tannins and flavonoids. Fourier Transform Infrared Spectroscopy was used to identify the major chemical groups in the extracted dyes.
Rotating Membrane Emulsification for Producing Single and Multiple Emulsions
Authors: Aryanti Nita , Williams Richard A.
Published: March 2018

Membrane emulsification is a technique utilising a novel concept of generating droplet ‘drop by drop’ to produce emulsions. The technique has several distinctive advantages over the conventional emulsification techniques.This paper concerns on the development of membrane emulsification (Rotating Membrane Reactor, RMR) which utilizes rotating tubular membrane to initiate droplet detachments. The RMR uses a rotating stainless steel tubular membrane with laser drilled pores (100 μm pore diameter) and a syringe pump to drive the dispersed phase through the membrane at a given flow rate. O/W formulations were prepared with low viscosity of paraffin wax, two types of emulsifiers, different membrane rotation rate and dispersed phase flow rate. The emulsion droplets exhibited a coefficient of variation of 9% and 81μm droplet size. In this research, the pore size/droplet size ratio could achieve 0.8. This value was below than other membrane emulsification processes. The effects of principal system operating parameters on both the average droplet diameter and droplet uniformity were discussed. In addition, a multiple (W/O/W) emulsion formulation was investigated as well.
Hydrogenation of Maltose in Catalytic Membrane Reactor for Maltitol Production
Authors: Makertihartha I.G.B.N. , Khoiruddin  , Hakim Ahmad N. , Aryanti P.T.P. , Wenten I.G.
Published: March 2018

Maltitol is one of the low-calorie sweeteners which has a major role in food industries. Due to its characteristics of comparable sweetness level to sucrose, maltitol can be a suitable sugar replacement. In this work, catalytic membrane reactor (CMR) was examined in maltitol production through hydrogenation of maltose. Commercial ceramic membrane impregnated with Kalcat 8030 Nickel was used as the CMR. The reaction was conducted at a batch mode operation, 95 to 110°C of temperature, and 5 to 8 bar of pressure. In the range of working conditions used in this study, up to 47% conversion was achieved. The reaction conversion was significantly affected by temperature and pressure. Results of this preliminary study indicated that CMR can be used for hydrogenation of maltose with good performance under a relatively low operating pressure.
The stability analysis of two-wheeled vehicle model
Authors: Gerlici Juraj , Sakhno Vladimir , Yefymenko Alla , Verbitskii Vladimir , Kravchenko Alexandr , Kravchenko Kateryna
Published: March 2018

This research investigates the stability of a two-wheeled vehicle model on the basis of numerical determination of full range of eigenvalues of a linear approximation matrix in the vicinity of the rectilinear driving mode. The received result was checked by numerical integration of the initial equations system of the disturbed motion of the model. The discrepancy of two research techniques is explained by the specialty of the considered mathematical model in which two pairs of complex conjugate eigenvalues close to each other are realized, that explains the emergence of standard derivations at calculating their numerical determination. The model is asymptotically stable in the range much wider than an operational interval (up to 100 m/s). In order to provide more intensive dampening of initial disturbances, it is possible to introduce additional resilient and damping elements between the trucks and the body in the design of the wheeled vehicle that will counteract the yaw mode of trucks.
Localization of delamination in composite test specimen
Authors: Sapieta Milan , Šulka Peter , Svoboda Martin
Published: March 2018

The main purpose of paper is presented an innovative approach in the field of infrared thermal imaging and its integration into the area of engineering applications. As the test specimen was selected composite rod with lengthwise composite fibers to each bonded. They have been excitated with ultrasound. For obtain the results was used Lock-in method. Last part of the paper is a description of the results and most appropriate settings of measurement technique for applications with chosen material.
Contribution to fatigue damage prediction of thin shell finite element models
Authors: Sága Milan , Vaško Milan , Kopas Peter , Piekarska Wiesława , Domański Tomasz , Kubiak Marcin
Published: March 2018

The paper deals with the implementation of the chosen fatigue damage criterions into FE analysis. Our study considers a shell finite element structural analysis in conjunction with the multiaxial rainflow counting and the fatigue damage prediction. The computational analysis considers stochastic response under random excitation in time domain and damage calculation based on so called critical plane approach (CPA).
Analysis and modeling of variables of the precise shredder’s pneumatic material transport’s system
Authors: Tyszczuk Krzysztof , Peszyński Kazimierz , Mroziński Adam , Śmigielski Grzegorz
Published: March 2018

The technological process of materials shredding, especially biological material, with a precise RPW shredder, requires control of its many elements. One of them, not methodologically recognized so far, is the flow of air conditioning an appropriate product’s quality and shredding capacity. In the article, there are presented the first results of studies of the process of pneumatic transport in a shredder, its analysis and simulation attempts, which shall make it possible to reach the optimum product’s capacity and quality, constituting the basis for biological diet supplements.
Inelastic damage using continuum damage mechanics in composite plate reinforced by unidirectional fibers
Authors: Žmindák Milan , Dudinský Martin
Published: March 2018

It is well that a finite element method is very popular simulation method to predict the physical behavior of systems and structures. In the last years an increase of interest in a new type of numerical methods known as meshless methods was observed. The paper deals with application of radial basis functions on modelling of inelastic damage using continuum damage mechanics of layered plate composite structures reinforced with long unidirectional fibers. For numerical simulations of elastic-plastic damage of layered composite plates own computational programs were implemented in MATLAB programming language. We will use the Newton-Raphson method to solve nonlinear systems of equations. Evaluation damage during plasticity has been solved using return mapping algorithm. The results of elastic-plastic damage analysis of composite plate with unsymmetrical laminate stacking sequence are presented.
Discrete element method approach to modelling VPP dampers
Authors: Chodkiewicz Pawel , Lengiewicz Jakub , Zalewski Robert
Published: March 2018

In this paper, we present a novel approach to modeling and analysis of Vacuum Packed Particle dampers (VPP dampers) with the use of Discrete Element Method (DEM). VPP dampers are composed of loose granular medium encapsulated in a hermetic envelope, with controlled pressure inside the envelope. By changing the level of underpressure inside the envelope, one can control mechanical properties of the system. The main novelty of the DEM model proposed in this paper is the method to treat special (pressure) boundary conditions at the envelope. The model has been implemented within the open-source Yade DEM software. Preliminary results are presented and discussed in the paper. The qualitative agreement with experimental results has been achieved.
Numerical analysis of stiffener for hybrid drive unite
Authors: Jakubovičová Lenka , Sága Milan , Handrik Marián
Published: March 2018

The matter of this article is a stress-strain analysis of hybrid drive prototype unit connected directly to convention Concrete Transit Mixer Gearbox. The unite was developed with intention to do field test on existing convection machines with possibility to use existing interfaces. The hybrid drive unit consists from electric and hydrostatic motor connected through addition mechanical transmission gearbox. The question is if today standard interface is good enough or need additional support a “stiffener”. Two engineering design were analysed. The first one includes using the stiffener to fixate the construction of hybrid drive unite connected to the planetary gear. The second one is without the stiffener. For strain-stress analysis, a finite element software ANSYS Workbench was used.
Lap weld joint modelling and simulation of welding in programme SYSWELD
Authors: Koňár Radoslav , Mičian Miloš , Zrak Andrej
Published: March 2018

Simulations of the welding process for applications of practice using SYSWELD are presented. This paper presents simulation of welding in the repair of high-pressure gas pipeline with steel sleeve with composite filling. Material of experimental sample was steel S355. The simulations in SYSWELD divided in to two parts: the thermal simulation followed by the mechanical simulation. The results of the numerical model, which are listed in article are compared to real experiments.
Study of the prototype mechanism of height adjustment of the bed in hospital bed
Authors: Malujda Ireneusz , Wilczyński Dominik , Talaśka Krzysztof , Wojtkowiak Dominik , Szulc Maciej
Published: March 2018

The presented kinematic system of the mechanism is an effect of a design process taking into an account design objectives specified by the medical staff in a hospital. In order to meet these requirements, a kinematic analysis of the mechanism was performed with the objective of finding a connection between various loads of the bed deck and the minimum force needed to drive the height adjustment mechanism. The next step was the validation process, performed by building the prototype of the studied machine on which the empirical tests were completed. During testing, the drive force of the mechanism was measured for various values and distribution of the load. The obtained results were compared with the results of the simulation analysis. This made it possible to reach the final research goal, which was to determine how to place all the mechanism parts in order to achieve the lowest possible drive force and fulfil all design objectives simultaneously.
Computer simulation of thermoforming process and its verification using a rapid tooling mould
Authors: Modławski Michał , Jaruga Tomasz
Published: March 2018

The results of computer simulation of thermoforming process made using ANSYS Polyflow software are presented in this paper. The analysis of the wall thickness distribution across an U-shaped thermoformed product manufactured using a positive mould was made. The simulation results were verified using a mould manufactured in a 3D printing process which was Fused Deposition Modelling (FDM) and a poly(ethylene terephthalate) formed sheet. It was proven that the computer simulation and a tool made with a Rapid Tooling technology can be useful for predicting the quality of a thermoformed part, particularly to find the problems with thin-walled areas.
Numerical analysis of laser welding with consideration analytical methods of determining phase transformations and mechanical properties of welded joint
Authors: Piekarska Wiesława , Goszczyńska-Króliszewska Dorota , Saternus Zbigniew , Domański Tomasz , Kubiak Marcin
Published: March 2018

The numerical analysis of laser welding process with consideration analytical methods determining phase transformations and mechanical properties of welded joints are presents in this paper. The analytical CCT diagram and final structural composition of S355 steel are presented. The empirical relations presents in paper are determined by chemical compositions investigated steel and cooling rate between temperatures 800-500°C (t8/5). Phase composition and mechanical properties each of structures of steel in weld and heat affected zone (HAZ) are determined on the basis of analytical methods. Laser welded flat is used in numerical simulations in ABAQUS. Mathematical modes of volumetric welding source are used in the calculations. Temperature fields, shape and size of melting zone for selected points in the cross-section of the joint are determined on the basis of thermal cycles obtained numerical.
The damage analysis of the reinforced concrete beam and the prestressed reinforced concrete beam
Authors: Vaško Milan , Handrik Marián , Rác Matej , Baniari Vladislav , Kortiš Ján , Daniel Ľuboš
Published: March 2018

The paper deals with the finite-element analysis of damage in reinforced concrete beam and prestressed reinforced concrete beam. The steel reinforcement is modeled using non-linear rebar elements and an elastoplastic model of the reinforcement is considered. The initial prestress is defined in the ropes that are used to create the prestressed reinforced concrete beam. These ropes are also modeled using non-linear rebar elements and the elastoplastic material model. Created computational model allows the damage modeling of the reinforced and pre-stressed reinforced concrete beams under static loading.
Analysis of inertial amplification mechanism with smart spring-damper for attenuation of beam vibrations
Authors: Barys Mateusz , Zalewski Robert
Published: March 2018

In this paper an inertial amplification mechanism with an embedded smart spring-damper device for attenuation of longitudinal vibrations in continuous structures is analyzed. The complex systems are the extension of the already investigated inertial mechanism, here additionally equipped with the vacuum controlled spring-damper device which shows features of smart materials. This allows the semi-active control to affect different frequency vibration ranges in the real time. The fea.tures of the basic inertia amplification mechanism are preserved as a possibility to generate two neighbouring anti-resonance frequencies between resonance peaks in the low frequency range.
The development of diagnostics methodological principles of the railway rolling stock on the basis of the analysis of dynamic vibration processes of the rail
Authors: Gerlici Juraj , Nozhenko Olena , Cherniak Ganna , Gorbunov Mykola , Domin Rostyslav , Lack Tomáš
Published: March 2018

The paper discusses the preconditions of the methodology development of diagnosis system for assessing dynamic impact of the rolling stock on the basis of processing and analysis of data obtained in operation on the results of measurement of parameters that characterize dynamic vibration processes of the mechanical system of “rolling stock – track”. On the basis of usage of the processing methods of time series and stochastic processes there has been established the relationship between these dynamic processes and wheel defects, and designed experimental data processing algorithms, which in the future will be an integral part of the intellectual systems of decision making when assessing the impact level of the rolling stock on the track. The article presents some results of the experimental and theoretical research of the rail accelerations data, which have been registered during passing of the train. The computational algorithm of the specialized pre-processing of the multidimensional signal recorded by this system is described. The advantage of this algorithm is that it does not require additional information about the train speed on the section equipped with the monitoring system, about the number of wheel pairs of locomotives and train cars, and about the distances between the wheel pairs. Based on the processing results of accelerations of the rails there have been set the parameters of increase in all statistical indicators with increase in the train speed. It is noted that the level of indicators for accelerations of the rails in the vertical direction is twice as high as the corresponding parameters in the horizontal direction.
Innovative wheel tread design aimed to tramcar-track interaction improvement when passing curves of a small radius
Authors: Hauser Vladimír , Nozhenko Olena S. , Kravchenko Kateryna O. , Loulová Mária , Gerlici Juraj , Lack Tomáš
Published: March 2018

Tramways in cities often ride in track curves of a small radius, which is followed by an increased effect of the vehicle on the track. In the rail - wheel contact often occurs creep in longitudinal as well as in lateral direction, which causes increase of riding resistance, wear in rail – wheel contact and noise operation. Exactly with the aim to reduce these undesirable effects we designed a tram bogie with steered wheelsets and with the double wheel tread. This inventions are registered by authors under Utility Model Nr. u201609015 and Patent Application Nr. a201701589. Description of proposed process of passing vehicle through strongly curved track is given in this paper. A comparison of creep velocities in rail - wheel contact results obtained by computer multibody simulations for a tram vehicle riding through a S-curve are presented. Purposefulness of proposed invention is investigated by constructing vehicle ride resistance dependence to the track curve radius.
Experimental research of vehicle traction properties for reconstruction of traffic accidents
Authors: Dudziak Marian , Lewandowski Andrzej , Śledziński Michał
Published: March 2018

In order to broaden the database of motor vehicle traction properties in unusual conditions, the research team has performed experimental studies: on wet and snow-covered surfaces. Tests of vehicles equipped with winter tyres with non-skid snow chains have been performed on snow-covered surfaces. It has been shown that on snowy surface chains affect vehicle traction properties, mostly during acceleration. They increase the rate of acceleration up to 50% compared to a vehicle with winter tyres without chains. The results of the performed research can be the basis for the full reconstruction of road accidents under these conditions. Knowledge of traction properties of cars in difficult and unusual conditions is an important cognitive factor and serves to improve road safety.
Experimental investigation of properties of GFRP foam cored sandwich joints
Authors: Gulanová Jana , Margetin Matúš , Gning Papa-Birame , Chríbik Andrej
Published: March 2018

Presented paper focuses on intermediate outcomes of the bilateral project between the Faculty of Mechanical Engineering, STU in Bratislava, Slovakia and the Institute of Automotive and Transport Engineering, UBFC in Nevers, France. Thus, mechanical properties and behaviour of glass fibre reinforced polymer composite foam cored sandwich panels joints were researched to estimate the best possible joint technology. Three-point bending and four-point bending were used to evaluate flexure strength and static force-flexure curve. Based on such testing, one specific joint composition was chosen to be broadly investigated. Finally, chosen type of joint panels was tested under four-point cyclic loading to obtain its fatigue properties.