bluuebunny/crossref_metadata_2025 huggingface dataset:
A low-cost media for leptolyngbya (cyanobacteria) strain growth isolated from indonesia as a potential biofuel feedstock
Authors: Rakhmayanti Nurul , Nurmarina Alinda , Prihantini Nining Betawati , Handayani Sri , Nasruddin
Published: November 2018

The study of a low cost media for Leptolyngbya growth had been done. Commercial NPK fertilizer was one of the low cost media that commonly used for microalgae growth. The objective of this study aimed to determine the best concentration of commercial NPK fertilizer for Leptolyngbya NBP-7A growth as a potential biofuel feedstock. Leptolyngbya NBP-7A was isolated from Cisolok hot spring, located in Indonesia. In this study, Leptolyngbya NBP-7A was grown in commercial NPK fertilizer with concentration 80 ppm, 240 ppm, and in BBM (Bold Basal’s Medium), BBM+NPK 80 ppm as a control. This strain was incubated on 35°C. Observation were made approximately 14 days with 2 sampling for each media. The average of wet weight Leptolyngbya NBP-7A after 14th day observation, was obtained at NPK 80 ppm was 5 mg/L, NPK 240 ppm was 4.1 mg/L, BBM was 19.75 mg/L, and BBM+NPK 80 ppm was 14.65 mg/L). The results of 14 days observation showed that the best concentration NPK culture media for growing Leptolyngbya NBP-7A was in BBM + NPK 80 ppm. This study showed that commercial NPK fertilizer could be used for Leptolyngbya NBP-7A growth as a potential biofuel feedstock.
Growth of mastigocladus (Cyanobacteria) HS-46 isolated from maribaya hot spring, indonesia in medium NPK as a potential biofuel feedstock
Authors: Nurmarina Alinda , Rakhmayanti Nurul , Prihantini Nining Betawati , Handayani Sri , Nasruddin
Published: November 2018

One of cyanobacteria genera which isolated from Maribaya hot spring located in Indonesia is Mastigocladus HS-46 can be used as raw material for biofuel production. Mastigocladus is cultured in commercial NPK fertilizer. Commercial NPK fertilizer is one of the low cost medium that commonly used for microalgae growth. The research aims to know the best concentration of commercial NPK fertilizer for Mastigocladus HS-46 growth. In this research, Mastigocladus HS-46 was grown in commercial NPK fertilizer with concentration 80 ppm, 240 ppm, NPK 80 ppm+BBM, and BBM (Bold Basal’s Medium) as a control. This strain was incubated on 35°C. Observation were made approximately 14 days with 2 sampling for each medium. The average of wet weight Mastigocladus HS-46 after 14 day observation was obtained at NPK 80 ppm: 0,019 g/L, NPK 240 ppm: 0.009 g/L, NPK+BBM: 0,014 g/L, and BBM: 0,015 g/L. The results showed that the best NPK medium concentration was 80 ppm for growth Mastigocladus HS-46. Commercial NPK fertilizer can be used for growth Mastigocladus HS-46 which has potential as biofuel feedstock.
Fatty acid characterization of indigenous cyanobacterial strains isolated from five hot springs in indonesia
Authors: Prihantini Nining Betawati , Handayani Sri , Sjamsuridzal Wellyzar , Yokota Akira , Nasruddin
Published: November 2018

Cyanobacteria have been known to produce lipids that are potential for biodiesel. Cyanobacteria isolated from Indonesia are called Indonesia indigenous cyanobacteria. This study was conducted to determine the characterization of fatty acids contained in cyanobacteria originating from Indonesia which were isolated from 5 hot springs in Indonesia. For some 29 strains of cyanobacteria consisting of 8 genera have performed the analysis of fatty acids (FA) by extraction method via protocol in SHERLOCK Microbial Identification (Midi) System version 4.0, 2001 MIDI, Inc. The resulting data is as follows. All strains of 8 genera (Synechococcus, Merismopedia, Thermosynechococcus, Stanieria, Leptolyngbia, Westiellopsis, Mastigocladus, and Nostoc) have saturated fatty acids (SFA) and unsaturated fatty acids (MUFA and PUFA). The content of saturated fatty acids ranged from 27.77 to 50.56%, while the content of unsaturated fatty acids ranged from 7.58 to 63.31%. All strains have SFA Palmitic acid (16:00) which ranges from 23.23 to 42.64%. Meanwhile, unsaturated fatty acids Palmitoleic acid (16:1 wc7) are owned by almost all strains except Westiellopsis which range from 1.75 to 51.78%. Content of unsaturated fatty acids Oleic acid (18: w9c) ranges from 1.43 to 35.78% mainly in Leptolyngbia, Westiellopsis, and Mastigocladus. All strains have MUFA ranging from 7.58 to 63.31%, whereas PUFA is only owned by filamentous strains (Leptolyngbia, Westiellposis, Mastigocladus, and Nostoc). From the results of the research can be seen that 29 strains of cyanobacteria of 8 genera have potential fatty acids as raw materials of biodiesel under certain conditions.
Preliminary Study Of Local Catalyst For Low Cost Methanol Synthesis As Subsequence Process Of A Model System Of Biomass Fluidized Bed Catalytic Gasification
Authors: Prasetyo Joni , Rahmawati Nurdiah , Murti Galuh Wirama , Sumbogo Murti S.D. , Puspitarini Tyas , Pertiwi Astri , Mirdayanti Fusia , Rosyadi Erlan , Hidayat Herman , Adiarso  , Sudo Yuta , Noda Reiji
Published: November 2018

Biomass waste has been emerging as an alternative energy and fuel. Direct combustion of biomass leads to harmful substances such as NOx and CO which are environmentally unfriendly manner. Innovation of clean technologies like gasification would have a potential in developing technology to reduce the emissions of harmful substances into the environment. The syngas of biomass gasification is an intermediate product which can be converted further to various types of alternative fuels especially methanol. Agency for the Assessment and application of Technology (BBPT)-Indonesia in cooperation with Gunma University-Japan has been conducting assessment and application of environmentally friendly solid biomass wastes utilization technology under the SATREPS (Science and Technology Research Partnership for Sustainable Development) program. This work is a prolongation of biomass gasification process from empty fruit bunches (EFB) to produce syngas. Furthermore, the syngas has a potential as raw material to synthesize methanol. The study of methanol synthesis focused on the development of efficient and low-cost catalyst in term of low pressure and low temperature. The catalyst of methanol synthesis was prepared by co-precipitation method with copper basis. The experiments have been performed and tested in a once-through process by Low-Pressure Fixed Bed Reactor in Micromeritics unit at a mild operating condition. The result shows that catalyst CuO: ZnO: Al2O3 (47%: 37%: 15%) has a good performance at 20 bar and 270°C with methanol concentration in the gas product up to 1.15%. On the words, the local catalyst performance comparable with commercial catalysts at low pressure and low temperature.
Estimating emission from gas power plant in palembang, indonesia using direct and indirect methods
Authors: Kristanto Gabriel Andari , Anantoputra Alditho Farrasi
Published: November 2018

Nowadays, almost every daily activity is supported by the availability of energy, especially electricity. As the Borang 60 MW Gas Power Plant in Palembang, Indonesia emits air pollutants such as SO2, NOx, CO, and total particulate matter (total PM), an emission inventory needs to be developed. Various methods can be used in the inventory of emissions; among others are a direct method based on direct measurement and an indirect method which involves the calculation of total emissions by emission factor. This study aims to estimate the emissions from the gas power plant in Palembang using direct and indirect methods and analyze the most suitable emission factor for Indonesian conditions. The comparison between emissions measured by direct and indirect methods found that the indirect method using the emission factor of AP-42 gives more accurate results for SO2 and NOx, whereas the total emission of CO is more accurately calculated based on the indirect method using the emission factor developed by Kurokawa et al. (2013); the median value of total PM is more accurately calculated based on the indirect method using the emission factor developed by the IPCC.
Betung bamboo-based activated carbon bioadsorbent for the separation of hydrogen-methane gas mixture
Authors: Sudibandriyo Mahmud , Oratmangun Melody
Published: November 2018

Hydrogen recovery from off gas of hydrocracking and hydrotreating unit is one of the crucial processes in an oil and gas refinery unit as this process helps in lowering the expenses for operations. This study aims to obtain activated carbon that is made from Betung bamboo which can be used as the adsorbent in this process. The activated agents used are H3PO4 and K2CO3, respectively. Each activation lasts for 30 minutes. The results of the characterization test shows that the Iodine number of the activated carbon produced reaches 916.4 mg/g with BET surface area of 465.2 m2/g. SEM-EDX analysis shows that the carbon content is 74.83%. The activated carbon obtained is used to separate Hydrogen and Methane from its mixture at 10, 20 and 30oC with pressure variations of 1 - 6 bar. The results indicate that the maximum number of moles adsorbed from CH4(21.5%)/H2 gas mixture is 0.247 mmol/g, that has been carried out at 6 bar with temperature of 10oC. Methane has 2.2 times higher adsorption capacity than hydrogen, therefore, the Betung bamboo based activated carbon produced from this research can be applied as the adsorbent in the separation process of CH4/H2 mixture and it fits the Langmuir model.
Hydrogen Recovery from Hydrogen-Methane Gas Mixture Using Coffee Grounds Based Activated Carbon Bioadsorbent
Authors: Sudibandriyo Mahmud , Kusumadewi Faracitra
Published: November 2018

Hydrogen recovery from off-gas of hydrocracking unit by adsorption is one of the process that could increase the efficiency processes of refinery unit. The purpose of this research is to make coffee grounds based activated carbon bioadsorbent that will be used in hydrogen recovery proses. The carbon was prepared by chemical activation using ZnCl2 at temperature 600°C. The surface area of produced activated carbon was measured using BET and Iodine number, while its surface morphology and composition were characterized using SEM-EDX. The adsorption capacity of activated carbon and its selectivity will be tested using hydrogen-methane gas mixture. The test was carried out on pure methane and hydrogen gas at 20°C and a mixture of CH4/H2 (mole ratio: 4:1) at 10°C, 20°C and 30°C and pressures from 1 to 6 bars. The results of this study show that the activated carbon can be successfully produced having the specific surface area of 728.07 m2/g and the iodine number of 2160 mg/g. The result shows that the adsorption of pure CH4 gas at the same pressure was 2.4 times greater than pure H2. The adsorption test indicates that the produced activated carbon might be used for hydrogen/methane separation.
Development of solar cell and fuel cell integration model and economic analysis in on grid and off grid system.
Authors: Prakoso Andy , Syahputra Erfan , Setiawan Eko Adhi
Published: November 2018

Electricity has become a very important needs for human life today and one of the parameters in one region condition. Nowadays, the dependence on fossil fuels to fulfill the electricity needs is really worrying, and it causes the depletion of fossil fuels. Today, the whole world is paying more attention to renewable energy as one of the best solution to solve the future energy problems. Renewable energy becomes the best solution because it will not be exhausted and enviromentally friendly. In the other hand, renewable energy also have problem, because it cannot produce energy everytime like photovoltaics which can produce energy only when there is enough solar radiation. Therefore, a hybrid system is made that expected to minimize the weakness from other components of the system. In this project, a hyrid system is designed using HOMER PRO software to calculate the electricity and economic factor of the hybrid system. The objective of this project is to find the best hybrid system that can solve the electricity problems. The system will be independent since grid function will replaced by fuel cell in the 19th year based on the assumption.
Optimization of cellulase production by bacillus sp. BPPT CC RK2 with pH and temperature variation using response surface methodology
Authors: Gozan Misri , Harahap Andre Fahriz , Bakti Chandra Paska , Setyahadi Siswa
Published: November 2018

Indonesia has abundant ethanol biomass feedstocks. However the second-generation ethanol production process is still hampered by the unavailability of cellulase enzyme in the process of decomposition of lignocellulose into saccharides that can be processed into ethanol through fermentation. Cellulase is known as exozyme produced byBacillus sp. in submerged fermentation. In this study, cellulase production byBacillus sp. CC BPPT RK2 on natural and abundant agricultural waste substrates (rice bran and coconut water) was evaluated by investigating the optimum conditions for cellulase production in a 50 ml laboratory scale. Preliminary test using Luria Bentani (LB) medium with additional CMC (1%) were done to select optimum range of pH and Temperature. The preliminary tests results were then followed by optimization of pH and temperature, which were carried out using response surface methodology (RSM). RSM optimization model showed optimum values 6.23 for pH and 40.04 °C, with 14 terms (each with 1 degree of freedom), 4 linear effects, 6 interaction effects and 4 quadratic effects. These optimization by RSM results were slightly different compared to preliminary test, showing the effect of interactions between parameters. The characteristics of interaction among variables tested against the cellulase activity are reported in this study including: positive effects on cellulase activity of the resulting responses; negative interactions affecting the response of cellulase activity; synergistic interaction; and antagonistic interactions between each other.
Comparison of two calculation methods for designing the solar electric power system for small islands
Authors: Romana Angga , Setiawan Eko Adhi , Joyonegoro Kurnianto
Published: November 2018

Electricity that produced by renewable energy sources are countinously increased, but some place in Indonesia have not utilize the renewable sources maximally, for instance Kolorai, South Morotai. Based on data from NASA, solar radiation in kolorai is around 5,99 kWh/m2/day, so solar power plant is one of solution to solve electricity needs in remote area like Kolorai. Futhermore, in solar power plant project, determining the load profile and designing the stand alone PV with simulation is important to make a great system. So the optimal methods are needed to build those system, the methods that have higher energy output, less excess energy, dan have a low Net Present Cost. In this paper, Australian/New Zealand standart and manual calculation are used to create an economical design. The result of the HOMER simulation shows that using Australian/New Zealand standart have a suitable result with excess electricity value is 8,56% and Net Present Cost is 1.439.160.000 rupiah.
Optimizing micro milling energy consumption for green manufacturing based on cutting strategies
Authors: Kiswanto Gandjar , Azmi Maulana , Averina Ignatia
Published: November 2018

Micro milling is currently being used to make micro-sized products, such as in MEMS, medical devices, etc. But in the process of machining, especially in roughing process, micro milling spends a lot of energy that can still be reduced to contribute to green manufacturing. This study focuses on developing the model of energy consumption during the micro milling processes. The model is then used to map the energy consumption from different cutting toolpaths and strategies. Furthermore this study also comparing and characterizing the energy consumed between macro milling and micro milling of the same part shape but with significant different in size. In conclusion, this study shows different characteristics and comparison in energy consumption between micro milling and macro milling.
An increase in bed temperature on gasification of dual reactor fluidized bed
Authors: Nyoman Suprapta Winaya I , Ketut Gede Wirawan I , Wayan Arya Darma I , Putu Lokantara I , Hartati Rukmi Sari
Published: November 2018

One of the main issues using biomass as fuel in air gasification is the dilution of its product gas by the nitrogen in the air. A dual reactor fluidized bed (DRFB) overcomes this problem in which the gasification and combustion reactions are decoupled and conducted in two separate fluidized bed reactors connected by circulating bed material. The DFRB unit made of 304 stainless steel pipe with a height of 100 and 150 cm, and inner diameters (i.d.) of 15.2 and 5.1 cm for gasifier and combustor respectively. The rice husk as fuel and quartz sand as bed material having the same size of 0.4 - 0.6 mm were applied in this investigation. Since the gasification process is an endothermic reaction, gasification temperatures are varied at 600°C to 700°C while combustion reactor were kept at 600°C using the electric heaters enclosed in ceramic cover. The superficial gas velocity in this study was kept constant at 17 m/s using the external air volumetric flux of the blower flow entering the DRFB loop. Gas gasification samples are then examined by gas chromatography to determine syngas content (CO, CH4 and H2). The test results showed that by the increasing temperature of the gasification reactor there was an increase in syngas especially CO gas conentration. The temperature increases in the gasification reactor (600°C, 650°C, 700°C) is able to increase the endothermic reaction in the gasification process which is dominated by CO gas production. The syngas efficiency was found to increase from 40.95% to 43.77%.as the temperature of the gasification reactor increased.
Effect of mother-in-law’s tongue leaves (Sansevieria trifasciata) extract’s solvent polarity on anti-diabetic activity through in vitro α-glucosidase enzyme inhibition test
Authors: Yumna Mauhibah , Angelina  , Abdullah  , Arbianti Rita , Utami Tania Surya , Hermansyah Heri
Published: November 2018

Diabetes Mellitus (DM) is a metabolic disease caused by elevated blood glucose levels above normal values (hyperglycemia). Natural ingredients that contain hypoglycemic substances, can become an alternative treatment of DM, i.e. mother-in-law’s tongue leaves (Sansevieria trifasciata), which is known to contain flavonoids, glycosides, alkaloid, and steroids that have anti-diabetic activity. The goal of this research is to obtain mother-in-law’s tongue leaves crude extract which has the highest anti-diabetic activity as an α-glucosidase inhibitor. The result showed that from all solvents used, which is aquadest, 70% ethanol, and 70% ethyl acetate, extracted with 70% ethanol has the highest yield value, which is 12.69%. The percentage of inhibition α-glucosidase was 90.72% at the inhibitor concentration of 4708.71. This shows that the extract with 70% ethanol has the required bioactive compound content to act as the α-glucosidase enzyme inhibitor. Based on the identification of compounds found in the sample mother-in-law's tongue leaves extract with 70% ethanol using Gas Chromatography and Mass Spectrometry (GC-MS), compounds that have anti-diabetic activity is steroids, alkaloids, terpenoids, tocopherol, and flavonoid.
The effect of increasing CO2concentration and flow rate on amine still performance in meeting gas sale specifications
Authors: Muharam Yuswan , Kristianto Hendra
Published: November 2018

The main purpose of this study is to examine the effect of increasing CO2removal and flow rate on performance of an amine still. The amine still is located in Field X in South East Sumatra at a new gas well producing gases with a rich CO2content. The still uses activated MDEA as the amine and has an IMTP 40-type packing column. Two film and desorption equilibrium curve theories were employed to analyse the amine still design conditions. Design equations were utilized to find the slope of the equilibrium curve. A slope of the equilibrium curve of 45° in the amine still is obtained in this study. The maximum liquid CO2composition of the amine still feedstock (xo) which can be separated to produce lean amine according to the specification design flow rate is 0.0307. The total flow rate of CO2-rich amine at xo= 0.029 is 761,157.6 kg/hour; the total flow rate of CO2-rich amine atxo= 0.0295 is 628,861.1 kg/hour; the total flow rate of CO2- rich amine at xo= 0.03 is 513,962.6 kg/hour; and the total flow rate of CO2-rich amine at xo= 0.0305 is 409,575.3 kg/hour.
Analysis of chemical volume and composition to overcome liquid loading in gas well
Authors: Wahid Abdul , Hidayat Muhamad Taufiq
Published: November 2018

Many problems often occur in producing natural gas from well. Due to the existence of water content in natural gas or water drive mechanism, liquid (especially water) is also produced from gas well, following natural gas production. When gas critical rate is higher than gas production rate due to reservoir pressure decline, it will cause liquid accumulation in the bottom of well, avoiding natural gas to be well lifted from well bottom to surface. It is liquid loading. Chemical injection of 0.4 liquid that consists of ethoxy sulphate, alkane sulphonate, and petroleum sulphonate is effective to overcome liquid loading in natural gas well thus causing an increase in natural gas production by 57%.
Control of Gas Dehydration Unit Using Multivariable Model Predictive Control (MMPC) to Obtain More Optimal Control Performance
Authors: Wahid Abdul , Mauricio Rickson , Maro Naufal Syafiq
Published: November 2018

A multivariable model predictive control (MMPC) is proposed to improve a control performance in Gas dehydration process. The FOPDT models are used to build an MMPC derived from the selected controlled variables (CV) and manipulated variables (MV). A set point (SP) tracking is used to test the control performance, with proportional-integral controller (PI) as a comparison. As an indicator of the control performance is the integral of square error (ISE). The result is a TITO (two-inputs two-outputs) MMPC, with sweet gas flow rate and heat duty of heater as MVs, and feed pressure and heater temperature as CVs, respectively. In the SP tracking test, MMPC showed better control performance than the PI controller with 11.29% performance improvement (pressure control) and 16.39% (temperature control).
The effect of activated carbon and silicon oxycarbide as anode materials on lithium-ion battery
Authors: Priyono Bambang , Egieara Natasha Chandri , Syahrial Anne Zulfia , Hudaya Chairul , Subhan Achmad , Jodi Heri
Published: November 2018

SiOC@C is a lithium-ion battery (LIB) anode candidate that is expected to suppress the high volume expansion of Si by the presence of activated carbon as a buffer layer. Silicon oxycarbide (SiOC) was obtained from phenyl-rich silicone oil through pyrolysis at 900°C with flowing Ar gas. The variation of samples used were 4 and 10wt.% SiOC and a pure carbon sample was also prepared for comparison. SEM images show a porous microstructure with a few chunks of agglomerate present. According to Brunner-Emmet-Teller (BET) test, the largest surface area of 542.738 m2/g was obtained at 10wt.%SiOC. Based on the performance test result, the highest discharge capacity of 223.3 mAh/g was obtained at the mentioned prime condition.
Optimization of Li4Ti5O12 (LTO) performance through the addition of ZnO-Nanorods using sol-gel solid-state method process as half-cell lithium-ion battery anode
Authors: Priyono B , Radiawan NY , Yuwono AH , Hudaya C , Subhan A , Sofyan N
Published: November 2018

Lithium-ion batteries have been a substantial power source for most electrical devices nowadays. Performance optimization for anode of lithium-ion batteries (LIBs) can be conducted by adding ZnO through sol-gel solid-state reaction. In this research, the Li4Ti5O12 (LTO) used was synthesized through sol-gel solid-state process and directly added with ZnO-nanorods obtained from aging and annealing process. LTO-ZnO obtained was characterized to determine the main phase and chemical composition by XRD and SEM-EDS respectively. Electrochemical performance of LTO-ZnO was tested by EIS, CV, and CD. ZnO-nanorods characterization with SEM-EDS results shows that the ZnO inside the LTO dispersed homogeneously. Characterization using XRD revealed that the ZnO successfully enter the LTO with the variation of amount of 4, 7, and 10 wt % of ZnO. Electric conductivity test shows improvement at an optimum addition amount of ZnO at 4 wt%, although BET result shows at the optimum amount of surface area with 96.459 m2/g. Electrochemical performance result shows optimum performance in ZnO at 4 wt% for its ability to withstand EIS test at 20C compared to 7 wt% and 10 wt%. Also, capacity of 4 wt% added is 150.8 mAh/g compared to 7 wt% with 134.1 mAh/g and 10 wt% with 118.3 mAh/g.
Synthesis and characterization of graphite/magnetite composite as low cost potential adsorbent from graphite waste
Authors: Kusrini Eny , Oktavianto Felix , Simanjuntak Agustina , Pasca Giovanni , Usman Anwar
Published: November 2018

The comparative properties of pre-treated graphite waste and composite with magnetite nanoparticles were studied. The present work describes the thermal-mechanical method for pre-treated graphite electrode waste and chemical modification on the pre-treated graphite waste with magnetite nanoparticles (Fe3O4). The raw material is graphite electrode waste. The variables of temperature and time that affected the properties of pre-treated graphite waste was also observed. Pre-treated of graphite electrode waste was prepared via thermal process at temperatures of 60, 75, 90°C and various times of 30, 60 and 90 minutes, followed by mechanical crushing of the resultant graphite waste to 75 μm particle size. The synthetic material (graphite waste/Fe3O4 composite) was prepared with hydrochloric acid (0.1 M) for activation of the pre-treated graphite waste, followed by chemical modification with pre-treated graphite waste to Fe3O4 mass ratio 1: 1 (w/w). The experimental results showed that the pre-treated graphite waste are non-porous. Effect of magnetite nanoparticles (Fe3O4) revealed that the surface area of graphite waste/Fe3O4 composite increased from 8.44 m2/g to 64.58 m2/g. The EDX composition of Fe increased from 0.08 to 38.68 wt%, indicated that the modification of Fe3O4 nanoparticles onto graphite waste was carried out successfully. This data is useful for the preliminary treatment process of graphite electrode waste for further applications that require adsorbent preparation and modification.
Effect of acid-assisted hydrothermal carbonization (HTC) process of tree branches using nitric acid on cadmium adsorption
Authors: Khoshbouy Reza , Lejiu Rico , Takahashi Fumitake , Yoshikawa Kunio
Published: November 2018

Application of acid in HTC process has been confirmed to have effect on hydrochar properties related to its adsorption capacity. Woody materials (tree branches) were used to investigate the relation of nitric acid addition in HTC process on the hydrochar surface properties and its adsorption mechanism toward cadmium in water solution. Tree branches were processed at 200-260 °C mixed with water and nitric acid (HNO3) at ratio 0-50% to hydrochar mass and held for holding time of 30, 105 and 180 minutes. Batch adsorption test was conducted by mixing the hydrochars with cadmium solution at 100 ppm and shaken for 24 hours at room temperature. The BET surface area, oxygen functional group (OFG) and the exchanged cations were analysed to investigate the effect of HTC process condition, nitric acid addition, and adsorption mechanism of cadmium. Tree branches treated at 200°C for 30 minutes and acid ratio of 50% showed the best adsorption result. Analysis on the surface properties also showed the best condition for cadmium adsorption. Thus hydrothermal treatment condition at low temperature, short time and high acid ratio usage could be effective in removing cadmium from water. The cadmium adsorption by cation exchange interaction might be the major adsorption mechanism as shown by consistency of trend of the exchanged cation concentration with cadmium adsorption capacit
Thermal performance of Pulsating Heat Pipe on Electric Motor as Cooling Application
Authors: Aprianingsih Nurhalimah , Winarta Adi , Ariantara Bambang , Putra Nandy
Published: November 2018

Heat generated in an electric motor can increase the operating temperature. The excessive operating temperature will reduce the electric motor performance and shorten the service life. An appropriate thermal management system is required to reduce the electric motor operating temperature. The objective of this study is to determine the thermal performance of pulsating heat pipes which applied to the electric motor thermal management system. A prototype of electric motor thermal management system was made from an induction motor with a cartridge heater instead of a heat-generating rotor and stator. Six pieces of pulsating heat pipe were mounted using hexagonal heat pipe holder which placed inside the electric motor housing. The pulsating heat pipes are made of a copper capillary tube using acetone as working fluid with a filling ratio of 0.5. The electric power input was varied from 30 W to 150 W. The use of pulsating heat pipes can reduce the electric motor surface temperature by 55.3°C with the minimum thermal resistance of 0.151°C/W.
The Effect of Mass Ratio of Ferrocene to Camphor as Carbon Source and Reaction Time on the Growth of Carbon Nanotubes
Authors: Wulan Praswasti Pembangun Dyah Kencana , Setiawati Nur Safitrah
Published: November 2018

This research aims to identify the best reaction time and mass ratio of camphor to ferrocene as carbon source in the growth of carbon nanotube (CNT). Ferrocene is used as carbon source and catalyst with stainless steel (SS)-316 type gauze as substrate.Camphor as alternative carbon source is intended to improve the CNT synthesis results. This research has shown that benzene, toluene, and xylene dominate camphor decomposition, so the addition will produce good quality CNT and increase the yield. The variation of mass ratio of camphor to ferrocene was 3:1, 2:1, 1:2, 1:3 and the variation of reaction time was 10,20,30,40, and 60 min. The synthesis results of the CNT were characterized using FESEM-EDS while the ferrocene and camphor decomposition gas was analyzed by GC-FID. The best quality of CNT was obtained at 1:2 mass ratio with yield 37%, carbon percentage of 76.98% and diameter of 77-151 nm. Increasing the reaction time from 10 to 20 minutes will increase the yield and quality of CNTs. The yield and quality of the CNT decreased after a reaction time of 30 minutes due to the deactivation of the catalyst and the closure of the active sites by nucleation and carbon growth.
Extraction and characterization of yeast extract bioethanol byproduct from empty palm oil bunch for raw material of cosmetic products
Authors: Sahlan Muhamad , Saefuddin Muhammad , Muryanto  , Hermansyah Heri , Wijanarko Anondho
Published: November 2018

Ethanolic fermentation can produce byproducts such as yeast containing intracellular amino acid that is used as a raw material of cosmetics. Residual yeast fermentation as sludge was dissolved and extracted by autolysis at 50°C for 24 hours, so we get the product in the form of intracellular content of the yeast Saccharomyces cerevisiae. Purification of dye and odor yeast extract was conducted by using an activated carbon column adsorption with ratio 1.5:10 yeast extract solution (g / mL) for six times recycle or until it reaches the absorbance value of 0.020. The content of yeast extract in the form of amino acids was analyzed by High-Pressure Liquid Chromatography method. Analysis of the feasibility test yeast extract as cosmetic raw materials made through the pigment deposition method by inhibit tyrosinase activity. 0.05 g yeast extract before adsorption (pale yellow) produce 62% inhibition of tyrosinase 3130 U / mL. Dry yeast extract after adsorption (odorless) had 96% inhibition of tyrosinase 313 U / mL, whereas placental extract by 89% inhibition of tyrosinase 313 U / mL. These results indicate odorless yeast extract can replace placental extract as an alternative to cosmetic raw materials.
Production of antipollutant mask with bamboo based carbon activated using H3PO4 and K2CO3
Authors: Sudibandriyo Mahmud , Jamil Shobrun
Published: November 2018

The increase of developing countries’ economic level has led to increase in air pollution problem. This research aims to make activated carbon based gas mask filter that was prepared from bamboo scraps by the combined activation using H3PO4 and K2CO3.Bamboo was selected as raw material because of its abundant availability and high cellulose content (42.4-53.6%).Dip coating was conducted to coat activated carbon on the surface layer of mask by adding TEOS compound.Furthermore, adsorption capacity of activated carbon was tested using compartment by flowing air containing CO and CO2 for one hour. The results of the characterization shows that the iodine number of the activated carbon produced reaches 916.3 mg/g with BET surface area of 465.2 m2/g. SEM-EDX analysis shows that the carbon content is 74.83%wt.Adsorption capacity of activated carbon was tested using compartment by flowing air containing pollutant gas and compressed air for one hour. The results indicate that the maximum number of moles CO2 adsorbed is 4.8 mmol/g with 7 hour saturated time,while adsorption capacity of CO measured in 1 hour test is 0.103 mmol/g. Therefore, activated carbon has met the standards and can be applied for gas mask filter to eliminate CO and CO2 until below safety limit concentration.
Optimizing characteristic of spirulina-polyvinyl alcohol (PVA) bioplastic through protein deformation with variation of heating time and solvent’s pH
Authors: Dianursanti  , Gozan Misri , Windiani Larasati , Sabathini Angelyn
Published: November 2018

Plastics that are widely used today are still made of synthetic polymers that are difficult to degrade by soil microorganisms. The development of natural polymer such as protein blend with synthetic polymer for bioplastic manufacturing continues. This study will utilize Spirulina platensis blended with synthetic polymers with heating and sonication as pre-treatment to optimize the characteristic. In this research, 2.5 g of Spirulina platensis powder dissolved in alkali and distillate water with pH variation of 7, 8.5, 10, and 11, then plasticized by glycerol and heating at 70oC with heating time variation of 30, 60, and 120 minutes. After that, blending with 2.5 g polyvinyl alcohol. Mixed solution then dried and formed as flex bar. Based on the results of solvent pH variation, the degree of acidity of the best solvent to produce optimum mechanical properties is a solvent with a pH of 10. The best heating time to produce optimum mechanical properties is 60 minutes at a solvent pH above 8.5. If using a solvent pH below 8.5, the best heating time is 120 minutes. Degree of solvent acidity is the most influential parameter on the bioplastic mechanical properties of Spirulina-PVA while the heating time has no significant effect.
The effect of NaOH (natrium hydroxide) to slag nickel pyrometallurgy in different temperature and additive ratio
Authors: Pangaribuan Rafaeldi Harlin , Patrick Juan , Prasetyo Agus Budi , Maksum Ahmad , Munir Badrul , Soedarsono Johny Wahyuadi
Published: November 2018

Nickel slag is one of the output from nickel ore smelting. In Indonesia itself, further utilization of valuable elements in it is needed to be processed. Nickel slag also has Fayalite (Fe2SiO4) content where nickel and copper are spread evenly on the iron matrix silica which then complicate the process of increasing nickel and copper content. The addition of Sodium Carbonate (Naoh) is used as a silica binder and as an alternative way to increase nickel and copper content. In this research, pyrometallurgy is done by coal as a reductor in 800°C, 900°C and 1000°C operating temperature and ratio between nickel slag and additive equal to 1:1, 1:2, and 2:1. Based on this study, it is obtained that with the increasing of temperature without additive, there is still found the presence of silica in a form of Fe-rich Forsterite (FeMgSiO4) and Olivine (NiMgSiO4). Whereas with the presence of additive in slag nickel pyrometallurgy with a different temperature and ratio, it is seen that there is a phase formation of Sdoium Magnesiosilicate (Na2MgSiO4), Magnesium Oxide (MgO) and Wustite (FeO) which proved the binding of silica and has liberate iron that helps the process of increasing nickel and copper content.
Usage period of nipah leaves nypa fructicans with salt water treatment as roofing material
Authors: Zakaria Umar Muhammad , Faslih Arman , Umar Mazhfia
Published: November 2018

At this time began to be revived the use of local materials. This is based on aesthetic and economic considerations. Therefore, researchers are encouraged to examine the knowledge of the utilization of local resources, especially nipah leaves. In Petoaha Sub District, Abeli District, Kendari City is located Kampung KB (Family Planning). Kampung KB is a former village of Bajo ethnic landed (formerly living on water). Mothers in Kampung KB are busy making roof material from nipah leaves. The leaves are taken from the palm trees that grow around Kampung KB. The phenomenon in the field that leaves soaked in sea water for 1-3 days before the roof is made. According to them that the leaves are soaked in sea water has a long lifetime compared to leaves that are not soaked in sea water. Based on their experience that watersoaked leaves have a lifetime for 3-4 years, can even reach 6-7 years when the roof thickness reaches 10 layers of palm leaves. Nipah leaves do not soak sea water has age wear for 2-3 years. This research is aimed to test the nipah leaf of marine water and nipah leaves do not soak the sea water against the period of usage. Metode plate count digunakan dalam penelitian ini. The plate count method to test the total microbial between fresh nipah leaf and nipah leaves is soaked in sea water. This study concluded that the bacteria on the nipah leaf soak the sea water is lower. Nipah leaves soaked sea water has a lifetime longer than nipah leaves do not soak sea water made roof material.
Experimental hydrodynamic analysis of trimaran-pentamaran with variation transom non-transom on mainhull and sidehull
Authors: Yanuar  , Sulistyawati Wiwin , Mahardika M Ammar , Alfarizsy A Azwin
Published: November 2018

One of the most essential aspects of ship is its resistance. There much have been done researches to analyze the reduction of resistance in order to get a good performance; yet the multihull is still one of interesting researches to get the rightest configuration, as to produce minimum resistance. This research is experimental study to obtain the lowest resistance with configuration consisting of stagger, clearance and trim of pentamaran. The pentamaran are performing as a trimaran formation by using Wigley hull with combinations transom on main hull and non-transom on side hulls. Its purpose is also to determine the destructive effects caused by wave interference. The research test conducted on stagger (a ratio of distance of stern main hull to stern side hull to main hull length)-positioning variations of 0.35 and 0.4. As for clearance (a ration of distance centerline of main hull to centerline of side hull to main hull width)-positioning variations, they exceed 1.05; 1.20; 1.35; and 1.50. The trim variations researched are 0°; 0.5 °; and 1.0 °. The result of this study was presented by tables and graphs of resistance components of side hull on stagger-clearance and trim condition.
Analysis of trimaran-pentamaran side hull location based on clearance and staggers with stern form variations
Authors: Yanuar  , Sulistyawati Wiwin , Yones R. Joshua , Mahardika Samodero
Published: November 2018

An optimum design of ship is to achieve the required speed with minimum power requirements. On multihull, sidehull position against to mainhull influences the friction resistance and its stability. Frictional resistance of multi-hull increases due to the addition of wetted surface area of hull, but wave making resistance can be lowered by a slender hull form. This research are experimental tests of trimaran with five Wigley hulls on a combination transom and without transom. The test varied on stagger, clearance and trim at several speeds. A ship with formation arrow tri-hull on forward was given to prove the resistance reduction due to cancellation wave which was indicated by negative interference. The influence diverse position of sidehull has shown that model non-transom (NT) stern moreover give beneficial resistance than model with transom (WT) at high speed. Similarly, in the trim conditions that NT more favorable on trim specifically for high speed depending on the position of the sidehull to the mainhull.
Combination of Coagulation-flocculation and Ultrafiltration Processes using Cellulose Acetate Membrane for Wastewater Treatment of Tofu Industry
Authors: Putri Sinta Sofiana , Kartohardjono Sutrasno
Published: November 2018

The tofu industry is generally a household-scale industry so that the efficiency of water used and wastewater treatment are mistreated. Wastewater from tofu industry is very hazardous when discharged directly into the aquatic environment as it contains high organic pollutants which is indicated by high concentrations of BOD (biological oxygen demand), COD (chemical oxygen demand), TSS (total suspended solid), TDS (total dissolved solid) and turbidity. The optimization of wastewater treatment process is needed to meet the quality standards set by the government and also needed to obtain more effective and efficient effluent treatment. The aim of this study is to evaluate the performance of combination coagulation-flocculation and ultrafiltration processes for tofu industry wastewater treatment. The process of pretreatment coagulation and flocculation using poly aluminum chloride (PAC) was conducted to extend the life of the ultrafiltration membrane and improve the performance of ultrafiltration membrane separation. The experimental results showed that TSS and turbidity decreased with precipitation time whereas COD did not significantly change. TDS after coagulation-flocculation has increased due to the addition of PAC. The TSS, TDS, COD and turbidity of wastewater were drastically reduced after experiencing ultrafiltration process. After the ultrafiltration process, the TSS, Turbidity, COD and TDS rejection were 98.8%, 98.1%, 71.0% and 50.6%, respectively.
Type and quality of energy and water in a tropical hospital
Authors: Prasetyadi Andreas , Koonsrisuk Atit
Published: November 2018

A hospital is considered an energy gobbler and a water consumer. The energy and water go for many activities in hospital system. HVAC that includes wet cooling tower is the main energy and water consumer in a hospital due to its continuous operation. Conservation of both resources partially depends on the way nexus is managed at the end user. Mapping the energy and water in term of type and quality is proposed as the starting point in managing both as nexus. This article focuses on that part in purpose of integrating energy and water system in a hospital. SUTH, a 120 beds hospital located in tropical area in Thailand that operates daily with 146 m3 water and 1.5 MW of electricity becomes the case of the study. The input and output of energy and water of each subsystem are exposed in addition to subsystems that are described in some different methods. The results show flows of energy and water as by-product that can be used for other systems. Radiology and HVAC release very low enthalpy heat that could not be managed for other utilization, but hemodialysis releases very low heat that is used for its own process. Autoclaves can releases heat that be used for laundry and its own pre-heating. HVAC release brine and distilled water through blow down system and condensation respectively. Electricity is very dominant energy supply of the hospital.
Ecological aspects of the traditional brick making process in pedurungan kidul, central java
Authors: Atmodiwirjo Paramita , Johanes Mikhael , Saginatari Diandra Pandu , Yatmo Yandi Andri
Published: November 2018

Traditional building materials play an important role in the construction of sustainable built environment. Clay bricks as traditional materials have been made with traditional techniques handed down across generation in many countries. The traditional process has become an integral part of the social and cultural life of the local society which forms the ecological relations between architecture and its context. The presence of the traditional process of brick making is currently challenged by the more modern industrial brick production. Some concerns have been raised regarding various environmental and health hazards from the brick making process. On the other hand, as a production process that has been handed down across generation, the brick making process is embedded with various ecological values that are attached to the environmental and cultural context where the production is performed and where the material resources are originated. This paper attempts to review ecological aspects that are involved in the traditional brick making production. In particular, this paper presents a preliminary analysis to identify the ecological aspects in brick making process in Pedurungan Kidul, Central Java, Indonesia. The findings suggest the need to consider the traditional brick making process as a comprehensive ecological system and therefore several research agendas are proposed for further investigation.
Sustaining the Culture of the City: Architecture and Cosmology in the Mantingan Mosque and Cemetery Complex in Jepara
Authors: Lie Ulin Nuha Allifna , Nurliani Lukito Yulia
Published: November 2018

This paper analyzes the architecture of the Mosque and the Cemetery Complex of Mantingan, in Jepara, Central Java. It is the basic idea in this paper that traditional local building philosophy may help to create cultural and social sustainability. The organization of the city especially shown at the city mosque and the cemetery reflect the culture of people live in the city and understanding the organization of the complex means sustaining the culture and the history of the city. The study will focus on understanding the connection of the architecture of the mosque and the cemetery complex in relation to Javanese architecture and cosmology. Based on this analysis, the finding of this paper is that theMantinganMosque and the Cemetery Complex adopted Javanese architectural forms and cosmology in the organization of the complex and help to sustain cultural, social and economic of the city.
Effect of Water Spray in Controlling Temperature of Hot Gas Propagation through Double Skin Facade
Authors: Purba Wolter , Dianti Afiri , Sigalingging Jefri , Gilang Ratnasari Nadhira , Nugroho Yulianto
Published: November 2018

The rapid development of science and technology have contributed in the applied building design. One of them is the improvement of the construction design of the building envelope. Current high-rise building design impacts in wider building envelop surface area and greater heat load received from the sun irradiation. One of the common used design is the doubleskin façade type building envelope. The insulation characteristic given by the envelope interlayer gap can reduce the heat load received. However, in fire cases, the gap becomes hot gasses path, supporting wider flame propagation. Its position in the outside leads to harder fire suppression effort. During this time, the active fire protection system design has just considering fire scenarios inside the building. This research is conducted to see water droplets impact as extinguisher aspect on interlayer gap hot gasses propagation. The experiment used wooden layer with 540 mm x 80 mm x 6 mm dimention as the envelope layer. The interlayer gap varies among others 30 mm, 50 mm, and 70 mm to see flame output characteristic through and time needed for 4 nozzles to extinguish the flame. The suppression system applied is expected to be a solution in the case of double-skin façade building envelope fire event.