bluuebunny/crossref_metadata_2025_split huggingface dataset:
Noise reduction in near infrared-based glucose concentration measurement sensor
Authors: Prawiroredjo K , Julian E S , Tjahjadi G 
Published: June 2019

Abstract
This paper describes the method of measuring glucose concentrations in solution using near infrared light (NIR) and photodiode sensor. A sensitive and accurate non invasive blood glucose level sensor is our main concern in designing this device. The sensor consists of a transimpedance amplifier, a notch filter and a low pass filter to reduce high frequency noise and 50 Hertz noise from the power line induction. Light Emitting Diode (LED) with 1450 nm wavelength is used as a light source and a photodiode is used as a sensor to sense this wavelength. The NIR light received by the photodiode after passing glucose solution is converted to voltage signal and filtered to determine the output voltage. The measurement results show that the filters reduced the AC voltage or noise signal under 100 mV and the DC voltage tended to decrease as glucose concentration increase until 700 mg/dL.
A New Geological Map of Formation Distribution on Southern Part of South China Sea:; Natuna Island, Indonesia
Authors: Kausarian H , Lei S , Lai G T , Cui Y , Suryadi A 
Published: June 2019

Abstract
Natuna Island is located at the outer part of the Indonesian territory and also as the end part of South China Sea at the south. Natuna consists of the islands that are surrounded by coral reefs and composed by sedimentary rock and sediment surface (alluvium). Natuna is a part of the Sunda group (Sundaland) which evolved through tectonic events (on the east) and volcanic activity, the formation of this island occurred in late Triassic time. Survey (field observation) applied for geological mapping by sample analyzing and tracking using handheld GPS. This research uses Natuna geological map from geological research and development center of Indonesia in 1994 with the scale of 1: 250,000 and interpretation of satellite imagery from the year 2015 with scale 1: 50,000 as reference material. The new spreading of formation distribution is seen in the Raharjapura Formation which has the lithology of alternating sandstone and repeating limestone spread across the north to the southwest and dominates the arrangement of formations in this island. Another new spreading occurs in the Eastern for Pengadah Formation, this formation has conglomerate lithology, sandstone aligned with Raharjapura’s formation. Hydrocarbon outcrop also found in the northeastern region of Natuna, this is a common thing because the Natuna islands are famous for its natural wealth of oil and gas. The final result is an updated geological map showing significant changes to the distribution of rock formations and alluvium and also propose the idea for developing this island as the vital area for Indonesian territory border.
Molecular Reidentification of Endophytic Fungus LBKURCC40 Isolated from Dahlia’s Tuber (Dahlia Variabilis) Using the Sequence of ITS rDNA
Authors: Suraya Nabella , Piska Finna , Pratiwi Nova Wahyu , Ardhi Aulia , Saryono  
Published: June 2019

Abstract
Endophytic fungus LBKURCC40 isolated from dahlia tubers (Dahlia variabilis) was morphologically and molecularly identified. Molecular identification was carried out using ITS4 and ITS5 primers, furthermore, the homology level of LBKURCC40 isolates was checked using BLAST program and the suitability of BLAST results was tested with the TrichOKEY program. The results of showed that LBKURCC40 isolates were identified as Trichoderma asperellum with a homology level of 99%. Phylogenetic analysis was carried out with N-J tree bootstrap test with 10,000 repetitions, and LBKURCC40 isolate was obtained to have the closest kinship to Trichoderma asperellum strain Tr266B.
Utilization of Molasses to Produce Lactic Acid by Using Lactobacillus Delbrueckii and Lactobacillus Plantarum
Authors: Nurkhamidah S , Altway A , Susianto  , Rahmawati Y , Taufany F , Hendrianie N , Ni’mah H , Gunardi I , Zulaikah S , Ningrum E O , Nyamiati R D , Ramadhani A 
Published: June 2019

Abstract
Molasses is the final liquid from the process of crystallization of sucrose in a sugar factory. In general this liquid is only disposed to the surrounding environment or used as a fertilizer mixture. However, this fluid still contains glucose that can be fermented into lactic acid. Lactic acid is a water-soluble compound commonly used in food, pharmaceutical and chemical industries. Through the polymerization process, lactic acid changes into polylactic acid (PLA) which is a biodegradable plastic. In general, PLA is made from corn. If PLA can be synthesized from molasses, it can reduce the use of corn as a raw material for making PLA and reduce waste in the sugar industry. This study aims to determine the optimal conditions of lactic acid fermentation by using sugarcane drops from Tulung Agung as a source of glucose and its purification so that it can obtain high levels of lactic acid. The results showed that fermentation with Lactobacillus plantarum could produce more lactic acid with faster fermentation time than the fermentation using Lactobacillus delbrucckii with a concentration of lactic acid 19.68 g/L.
Characterization of Zeolite A from Coal Fly Ash Via Fusion-Hydrothermal Synthesis Method
Authors: Wulandari W , Paramitha T , Rizkiana J , Sasongko D 
Published: June 2019

Abstract
Zeolite A has been successfully synthesized from coal fly ash by using fusion followed by hydrothermal method. This paper describes the characterization of zeolite A. The effects of hydrothermal time, Si/Al molar ratio, and alkalinity in the converting coal fly ash to zeolite A were also investigated. The coal fly ash was obtained from a local power plant at East Java, Indonesia and contained major oxides such as SiO2 (18.60 wt%), Al2O3 (7.18 wt%), Fe2O3 (40.20 wt%), CaO (25.20 wt%). The fusion hydrothermal method consists of the following steps: pre-treatment, fusion of coal fly ash with sodium hydroxide, aging, and hydrothermal process. The synthesized material was characterized by using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR), and specific surface area analytical method. The results show that the products contain zeolite A as the major phase, while the highest specific surface area of zeolite A is 37.121 m2/g. It implies that zeolite A as a higher value added product can be obtained from a solid waste/by-product of power plant, which has wide range applications, including for ion exchange and heavy metal adsorbent from waste water.
Natural Rubber Powder Production from Latex
Authors: Abidin A Z , Winartha N R , Rahardi I , Trirahayu D A 
Published: June 2019

Abstract
Natural rubber-based products are widely used in everyday life. There are three types of upstream processed natural rubber, that are crumb rubber, conventional rubber, and concentrated latex. Latex is easily damaged by clotting and contains 35-40% w/w of water so that the packaging volume is relatively large and inefficient in transportation. Latex also contains ammonia as an anti-clotting agent so the packaging must be special to prevent unpleasant odour. This study aims to create a pilot plant of the spray drying latex from simulation results then test the performance, evaluate the performance test results, as well as making improvements to the production of rubber powder. The steps of this research are data collection for spray dryer design, design verification, construction of spray dryer, spray dryer appliance testing, and characterization of rubber powder produced. The heating system used in the spray dryer is LPG gas-fired furnace. Testing is done by varying the spray dryer drying air temperature of 120°C, 150°C, and 180°C, the water content of the feed latex 70% and 80% w/w, as well as non-stick material such as talc powder and MgO. Rubber powder characterized by water content with digital tools moisture meter and analysed spectra with Fourier Transform Infrared Spectroscopy (FTIR). The results showed the optimum operating conditions for the production of natural rubber powder is drying air temperature of 150°C and the water content of the feed latex 80% w/w. Natural rubber powder produced contains 10 to 13% w/w water but still sticky so that the powder grains stick to each other. The FTIR spectrum analysis of natural rubber powder products show similarity with bonding group of polyisoprene natural rubber compound. Natural rubber powder product can also be used as a substitute for crumb rubber.
Melt Rheological Properties of Polypropylene/Clay Nanocomposites Prepared from Masterbatch: Effect of Nanoclay Loadings and Reprocessing
Authors: Chafidz A. , Ma’mun S. , Fardhyanti D. S. , Kustiningsih I. , Hidayat A. 
Published: June 2019

Abstract
In the present work, polypropylene (PP) and nanoclay in the form of masterbatch were melt compounded using a co-rotating twin screw extruder to fabricate polypropylene (PP)/clay nanocomposites. PP/clay nanocomposites samples with four different nanoclay loadings (i.e. 0, 5, 10, and 15 wt%) were prepared. Additionally, to study the effect of reprocessing on the properties of the nanocomposites, the melt compounding process was carried twice/recycle (i.e. 1st cycle and 2nd cycle). The surface morphological of the nanocomposites and their melt rheological behavior were investigated using a Scanning Electron Microscopy (SEM) and an oscillatory rheometer, respectively. The SEM micrographs showed that the nanoclay was well distributed in the polypropylene matrix for both 1st and 2nd cycles. While, the dispersion state of the nanoclay (either intercalated or exfoliated) could not be observed due to the limitation of the apparatus. Additionally, the melt rheological analysis results showed that the complex viscosity, |µ*| of all nanocomposites samples (for both 1st and 2nd cycles) were higher than the neat PP and the |µ*| also increased with the increase of nanoclay loadings. However, the 2nd cycle showed a slightly higher improvement of |µ*| compared to the 1st cycle, and the improvement of |µ*| was more prominent at lower angular frequencies (e.g. 0.1, 1, 10 rad/s) than at higher ones (e.g. 100, 500 rad/s).
Mixing Solvent’s Effect to the Characterization and Performance Cellulose Acetate/Polyethylene Glycol Membrane
Authors: Nurkhamidah S , Rahmawati Y , Taufany F , Fahrizal Y E , Ramadhan I H 
Published: June 2019

Abstract
The need for clean water continues to increase. Therefore, it is necessary to find an alternative for the get of clean water. One way is desalination process using membrane. Cellulose Acetate/Polyethylene Glycol (CA / PEG) membrane is one type of membrane that can be used for desalination process. Several studies on the manufacture of CA / PEG membranes have been performed, but have not yet produced a good performance membrane. Therefore in this research was synthesize CA/PEG/mixing solvent membrane using Acetone – THF/Acetone – DMF as the solvents at ratio 100-0, 90-10, 70-30, 50-50 (%volume) each and PEG as the additive vary PEG 200 and 400. CA/PEG/mixing solvent membrane characteristics are tested. The results showed that the hydrophilicity of mixing solvent method using Acetone-DMF (50:50) increase water content up to 375.86% and Acetone-THF (50:50)’s water content increase up to 177.10% with additive PEG 200, and for PEG 400 as additive showed that the hydrophilicity of mixing solvent method using Acetone-DMF (50:50) increase water content up to 503,86% and Acetone-THF (50:50)’s water content decrease from 173,28 % till 119,23%, as THF content increase.
Optimization of LNG Logistics System to Meet Gas Supply at Gresik LNG Receiving Terminal
Authors: Raharjo M , Sudibandriyo M 
Published: June 2019

Abstract
The construction of Gresik LNG receiving terminal is aimed to fulfil the 109 MMSCFD (0.87 MTPA) gas requirement for combined-cycle power plant (PLTGU) Jawa-3 which is integrated with LNG Gresik Terminal. There are several potential LNG plants in Indonesia and abroad that can be the source of gas for Gresik LNG Terminal. Each of these LNG plants has varying gas price and distance to Gresik. The modelling of the LNG logistics system for Gresik LNG Terminal was built to illustrate the LNG supply chain from the LNG plants to Gresik LNG Terminal and several supply scenarios will be proposed. The built model is linear and optimized by using linear programming. Linear programming involves the determination of objective functions, decision variables and constraints. The optimization of the logistics system aims to obtain the cheapest gas supply cost for Gresik LNG receiving terminal. The result shows that the cheapest gas supply cost is obtained through direct supply scenario with gas source from domestic and abroad with combination of delivery from Bontang equal to 0.34 MTPA (40 %) with 12 shipments, Tangguh equal to 0.26 MTPA (30 %) with 9 shipments, and Bintulu Malaysia equal to 0.26 MTPA (30 %) with 9 shipments.
A Sustainability assessment of biogas plant based on fruit waste in Indonesia: case study of Biogas Plant Gamping, Yogyakarta
Authors: Marendra F , Prasetya A , Cahyono R B , Ariyanto T 
Published: June 2019

Abstract
The production of biogas by anaerobic digestion (AD) from fruit waste and then converting biogas to electricity is an innovative approach in the development of renewable energy. To study the sustainability of the process, it important to analysis the environ-socio-economic benefits of the technology. In this study, the life cycle sustainability assessment (LCSA) were carried out in a fruit waste biogas plant system, which located in the Gemah Ripah Central Fruit Market in Indonesia. The AD system was designed for 4000 kg/day feed and supplies 148.5 kWh/day electricity. The results of assessment of environmental, economic and social aspects are 5.00 (very good), 3.00 (moderate), and 4.00 (good). This study indicates that biogas plant from fruit waste has a significant advantage for environment, economic, and society. Overall, the sustainability of BPG is in the category of very good (grade I) with a value 4.11 from maximum value of 5.
Effect of Biomass Composition and Co-pyrolysis Retention Time on Reduction of Non-neutral CO2 Emission from Combustion of Hybrid Coal in Power Plant
Authors: Handoko S , Wulandari W , Rizkiana J , Ridha M A , Prasetyo H A , Sasongko D 
Published: June 2019

Abstract
Indonesia’s lignite coal and sawdust production are 131,05 and 11,82 million tonnes, respectively, which are potential to become raw material of hybrid coal through co-pyrolysis. Hybrid coal utilization will reduce non-neutral CO2 emission, a part of CO2 emission released from combustion of biomass. The aim of this study is to determine the effects on biomass composition and co-pyrolysis retention time on reduction of non-neutral CO2 emission from combustion of hybrid coal in power plant. Co-pyrolysis was conducted in a vertical tubular furnace under an inert condition in atmospheric pressure and temperature 300° C. Biomass composition and co-pyrolysis retention time was varied from 20 to 40 %-mass and from 30 to 90 minutes, respectively. Hybrid coal was characterized with proximate, ultimate and calorific value analysis. The result of analysis was used as an input on simulation to determine reduction of non-neutral CO2 emission on hybrid coal combustion in power plant. An increase in co-pyrolysis retention time (CRT) from 30 to 90 minutes increases the CO2 emission from 13.25 to 13.30 %-vol. While increase in biomass composition from 20 to 40 %-mass reduce CO2 emission from 13.18 to 12.81 %-vol. Non-neutral CO2 emission reduction rises from 24.22 to 26.86 % along with the increased of biomass composition from 20 to 40 %-mass. Average of non-neutral CO2 emission reduction is about 26.30 % in all variation. CO2 emission of hybrid coal as fuel for power plant increased along with the increased of co-pyrolysis retention time (CRT), which was about 780-830 kg CO2/MWh. The highest CO2 emission was achieved from co-pyrolysis product hybrid coal utilization with 30 %-mass of biomass composition.
Fabrication of Interlayer-free P123 Caronised Template Silica Membranes for Water Desalination: Conventional Versus Rapid Thermal Processing (CTP vs RTP) Techniques
Authors: Elma M , Setyawan H , Rahma A , Pratiwi A E , Rampun E L A 
Published: June 2019

Abstract
This work demonstrates the comparison techniques between conventional and rapid thermal processing (CTP Vs RTP). It is to fabricate the interlayer-free P123 carbonised template silica membranes. The aim of this work is to understand the performance of fabricated membranes for water desalination. The silica sols pH 6 were prepared from a two acid-base catalyzed sol gel method by applying tetraethyl orthosilicate (TEOS) as the precursor. Triblock copolymer of Pluronic P123 was used as the templating agent and mixed homogenously with silica sols. The mixtures were calcined in two method called CTP and RTP. CTP is a slow calcination and takes 4 hours with 1 °C min-1 for dwelling time. On the other hand, RTP is rapid technique calcined in air (1 h without dwelling time). CTP confirms higher surface area (50 % higher), porosity (34 % higher) and thinner (60 %) than RTP. RTP technique is supposed to save time, energy and cost during membranes fabrication.
Microfiltration of Oily Waste Water: A Study of Flux Decline and Feed Types
Authors: Sutrisna P D , Candrawan J , Tangguh W W 
Published: June 2019

Abstract
In recent years, membrane separation techniques gain an increasing interest to be applied in many industrial separation processes, such as the separation of produced water in petroleum industry and the treatment of used oil and used cooking oil. Used oil and used cooking oil consist of suspended solids in addition to emulsion. Both ultrafiltration and microfiltration have been used to separate oil from water. The challenges of oil-in-water emulsion separation include the possibility of big oil drops deforming through the slot or pore of membrane thus reduce the oil rejection. In addition, concentration polarisation and fouling phenomena are considered as negative attributes for membrane performances. This research applied flat sheet microfiltration membranes to treat used oil and used cooking oil. The performances of membranes in terms of flux reductions were evaluated and analysed using filtration model. Experimental results showed the decline of permeate flux with time indicating the formation of polarisation layer on the surface of the membrane. In addition, complete blocking and deep bed filtration explained the flux behavior of used oil and used cooking oil filtration, respectively.
Lignocellulosic Properties of Coffee Pulp Waste After Alkaline Hydrogen Peroxide Treatment
Authors: Pudjiastuti L , Iswanto T , Altway A , Ningrum E O , Widjaja T 
Published: June 2019

AbstractThe effect of alkaline hydrogen peroxide (AHP) treatment on reducing lignin content in coffee pulp waste (CPW) was investigated to increase the digestibility and accessibility of cellulose during production of valuable products by enzymatic and biological process. Hydrogen peroxide (H2O2) at various concentrations (2.5, 5, and 7.5% (w/w of substrate)) was mixed into 10% (w/v) of CPW-NaOH solution at 35 °C for 24 h with pH 11.5. The concentration of lignocellulosic content was investigated. The characteristic of crystallinity index, functional groups, and surface morphology of CPW at before and after the treatment have been observed using XRD, FTIR, and SEM analysis, respectively. The results showed that the highest lignin removal was achieved at the addition of 7.5% H2O2which decreased from 16.85% to 8.5%. The concentration of cellulose and hemicellulose in CPW increased from 53% to 64% and 11% to 24%, respectively. The crystallinity index of AHP-treated CPW has increased from 30.83% to 42.08%. A surface morphological destruction on the CPW was getting worse as along with the increase of H2O2concentration. This would be useful to increase the porosity of biomass to give cellulose accessibility by enzyme for further processes.
Influence of Shewanella oneidensis MR-1 Bacterial Metabolism Process On Waste Treatment Of Cr And Mn Metals In Reactor Microbial Fuel Cell (MFC)
Authors: Juliastuti S R , Darmawan R , Hendrianie N , Prakoso G A , Bachtiar T A 
Published: June 2019

Abstract
Chromium (Cr) and manganese (Mn) are heavy metals which have high oxidation potential and cause mutagenesis and carcinogenic to living organisms. Microbial Fuel Cell (MFC) appears as one of the applications in the processing of Cr and Mn metals. MFC is bioreactor which converts chemical energy of organic compounds into electrical energy through the catalytic reaction of microorganisms in anaerobic conditions. The aim of this research are to find out the role of Shewanella oneidensis MR-1 bacteria on manufacture electrical energy by utilizing organic wastes, and to find out the concentration of Shewanella oneidensis MR-1 on the most influential anode side for the reduction of metallic Cr, Mn, and its mixed metal on the cathode side by using a MFC. The research method used molasses with bacteria concentration of 10%; 12.5%; 15% (v/v) on the anode side, while on the cathode side was used Cr(VI), Mn(VII) solutions, and mixtures of Cr and Mn solutions with the ratio of 1:0; 0:1; 1:1 (w/w). 15% bacteria concentration on mixture of metal solution resulted the highest electricity production, which was 46.33 (mW/m2), and the best reduction of Cr6+ to Cr3+ 82.15%, while for the reduction of Mn7+ to Mn2 was 61.17%.
Calcium Performance in Paper Sludge Ash as Suppressing Material
Authors: Desfitri E R , Hanum F F , Hayakawa Y , Kambara S 
Published: June 2019

Abstract
Paper sludge (PS) ash is a waste material collected from the paper industry, which containing calcium compound. In the previous research, several paper sludge ashes have been tried into coal fly ashes in order to suppress the leaching of trace elements such as As, Se, and B into the environment. The result showed that paper sludge ashes has potential effect in inhibit the leaching of these trace elements because of the calcium contains in the paper sludge ashes. Therefore, this research provide information about the amount of calcium in paper sludge ash as suppressing material. Nine kinds of paper sludge ashes tested into coal fly ash C (FA C) in order to know the ability of each paper sludge ash in suppressing the leaching of trace elements. Inductively coupled plasma (ICP-AES) used to determine the leaching concentration of As, Se, and B. Then, the kind of calcium in paper sludge ashes were analysed by X-ray diffraction (XRD). Thermal gravimetric analysis (TG) used to determinate Ca(OH)2 and CaCO3. The percentage of CaO in paper sludge ashes analysed by combination ethylene glycol, ICP-AES and TG. This research found the kind of PS which most influential for controlling leached out of trace elements.