bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of linear transducer calibration system using laser interferometer based on the Abbe principle
Authors: Rahman A , Pratiwi E , Alfiyati N , Novyanto O , Hedrony O 
Published: January 2021

Abstract
The validity of the measurement results can be guaranteed by performing calibration using a measurement standard traced to the international system of units (SI). The linear transducer is a measurement standard that is used to calibrate calibration tester, dial gauge tester, and gauge block in the calibration and testing laboratories. The critical position of the linear transducer in the traceability chain leads to the need for an optimal system to calibrate it with the smallest error and highest accuracy. As an optimization step, this research was carried out to improve linear transducer calibration performance using a laser interferometer combined with a universal length machine (ULM). The laser interferometer, ULM, and linear transducer were aligned with the Abbe and cosine principles. The results show a significant reduction of the linear transducer measurement error in the forward and backward directions by 548% and 119%, respectively. The measurement uncertainty could also be decreased by 8% to 0.18 µm.
Development of a rapid-test method for the determination of calcium, zinc, phosphorus, and sulfur in automotive engine oil by WD-XRF (wavelength dispersive x-ray fluorescent)
Authors: Cahyadi D , Susilowati E , Arsyansyah M , Febriany S 
Published: January 2021

Abstract
This study describes a rapid method for the determination of calcium, zinc, phosphorus, and sulfur in lubricating oil products using WD-XRF (Wavelength Dispersive X-ray Fluorescent). Currently, there are several normative references appointed by the mandatory SNI (Indonesian standard) used for elemental analysis in automotive engine oils, i.e., ICP-AES (Inductively Coupled Plasma - Atomic Emission Spectroscopy), AAS (Atomic Absorption Spectrophotometry) for calcium, zinc, or magnesium; ED-XRF (Energy Dispersive X-ray Fluorescent) for sulfur, lamp method for sulfur, and quinoline phosphomolybdate method for phosphorus. The wet chemical analysis principle used in those reference methods (AAS, ICP-AES, and conventional method) needs a sample preparation step before the main instrument can use to measure an oil sample. It is a time-consuming process and commonly consists of a few steps such as dilution, weighing, heating, and destruction. The statistical characteristics (limit of detection, the limit of quantification, precision, accuracy, and linearity) obtained in this experiment were relatively acceptable. Elemental analysis by WD-XRF needs no sample preparation process, fast, less chemical reagents, multi-elements, simultaneously, and simple. The WD-XRF method potentially could be used as an alternative method for the determination of certain elements (Ca, Zn, P, S) or more as specified in the mandatory SNI for automotive engine oil products.
Phenol degradation by fenton reaction in air injection using plasma electrolysis method
Authors: Wahono J Z , Yusharyahya R D , Harianingsih  , Saksono N 
Published: January 2021

Abstract
Phenolic compounds are pollutants which have high toxicity and could be harmful to the environment even at low concentrations. The degradation of phenolic has been conducted by various methods including photocatalytic and ozonation. However, these methods require high costs and large energy. Therefore, plasma electrolysis by the Fenton reaction may be an alternative method for phenol degradation. The purpose of this study is to determine the optimum conditions for phenol degradation by adding Fe2+ ions. The result shows that the most effective phenol degradation was obtained by using an optimum power of 700 watts with an air injection flow rate of 0.2 L/min and addition Fe2+ 20 ppm ions for 30 min experiments. Based on these conditions, the concentration of phenol in waste was reduced to 0.425 mg/L and the highest percentage of phenol degradation (99.58%) was observed. The final phenol concentrations obtained in this study met the quality standards for clean water at a concentration of 1 mg/L as well as the quality standards for drinking water treatment at a concentration of 0.5 mg/L.
The effect of sodium bicarbonate ratio for the mechanical properties of underarm pads rubber for crutches
Authors: Nasruddin  , Bondan A T , Agustini S 
Published: January 2021

Abstract
Research on the effect of the ratio of sodium bicarbonate on the mechanical properties of underarm crutch pads from natural rubber SIR-20 has been carried out. The ratio of sodium bicarbonate used was 1.00 phr; 1.50 phr; 2.00 phr; and 2.50 phr. The rubber compound for underarm crutch pads was made by the compounding process using an open rubber mixing mill and vulcanization at a temperature of 120 °C for 11 minutes. The best formula for curing characteristic rheometer test results at a temperature of 150 °C was URC-04 with Smax = 4.95 kg/cm, Smin = 0.44 kg/cm, ΔS = 4.51 kg/cm, t90 = 6.57 min and ts2 = 4.13 min. The mechanical test result showed the hardness test before aging and after aging of 31 Shore A, and 32 shore A, tear strength of 8.50 kN/m, elongation at the break before aging and after aging of 300%. The results of the identification of functional groups by FTIR for infrared absorption in each sample generally showed the same pattern with one another. SEM analysis result showed the distribution of materials and the formation of pores by sodium bicarbonate was not evenly distributed with an average diameter of 5 microns.
Characterization of 17-4 PH stainless steel metal injection molding feedstock using mixing torque data
Authors: Virdhian S , Doloksaribu M , Supriadi S , Balfas N M , Suharno B , Shieddieque A D 
Published: January 2021

Abstract
Currently, there are many components produced by a metal injection molding process in automotive, consumer goods, medical, and electronics. Metal Injection Molding process (MIM process) consists of four stages, mixing, injection molding, debinding, and sintering. Feedstock plays critical roles in the MIM process since the feedstock’s low quality cannot be corrected later. Feedstocks, which are a mixture of powder and binder, are mixed at an elevated temperature. A feedstock should be homogeneous and has a pseudo-plastic behavior. In the MIM process, the shear rate during injection molding is usually 10 to 10 000 s-1. Within the shear rates range, a maximum viscosity for injection molding was 100 Pas at molding temperatures. In this paper, the rheological characteristic of feedstocks was analyzed using the torque rheometer. The objective of this research was to find the value of viscosity and compare to the Material Safety Data Sheet (MSDS) of the commercial feedstock by using torque mixing data. All the three feedstocks had pseudo-plastic behavior and below 100 Pas within shear rates range. Form the validation of injection molding experiment, feedstock B with solid loading 60 %, and binder system consists of 35 % PP, 64% PW, and 1 % SA showed a good flowability and moldability.
The effect of chelating agents on the formation of manganese oxide (MnO) in the synthesis of sodium manganese oxide (Na2Mn3O7)
Authors: Marlina H A , Sebayang K , Gea S , Noer Z , Septawendar R , Sunendar B 
Published: January 2021

Abstract
This current study successfully synthesized Na2Mn3O7 in two steps. Firstly, the synthesis of MnO from NaCl and MnCl2.4H2O precursors. NaCl was mixed with citric acid as a chelating agent, while MnCl2.4H2O was mixed with two types of chelating agents (citric acid and 1% chitosan). The solutions of [NaCl-a chelating agent] and [MnCl2.4H2O-a chelating agent] were stirred for ±2 hours. The solutions were hydrothermally heated at 150°C for 6 hours and then calcined at 800°C for 1 hour in a nitrogen condition. The MnO presence was then analyzed using an XRD method. As a comparison, another sample was water leached. Then, it was examined by an XRD method. Secondly, the synthesis of Na2Mn3O7 from MnO and Na2CO3 powder was carried out through a solid method. The calcination was carried out at 800°C for ±3 hours in an oxidizing atmosphere. The XRD results showed the presence of Na2Mn3O7 in the final products of both samples. Based on these experimental results, the sample [NaCl-citric acid; MnCl2.4H2O-1%chitosan] showed higher purity than the sample [NaCl-citric acid; MnCl2.4H2O-citric acid], so that it had a higher intensity of the Na2Mn3O7 phase than the sample [NaCl-citric acid; MnCl2.4H2O-citric acid]. Besides, the Cl- ions removal after calcination greatly affected the intensity of the MnO and Na2Mn3O7 formed.
The comparison of cathodic and anodic plasma electrolysis performance in the synthesis of biodiesel
Authors: Saksono N , Pranata J J C , Muharam Y , Harianingsih  
Published: January 2021

Abstract
Synthesis of biodiesel using plasma electrolysis is very promising. This study aims to understand the differences between cathodic and anodic plasma performance in synthesizing biodiesel from palm oil. The raw materials used were palm oil, methanol, and KOH catalyst. In the present study, the effects of the type of plasma and the depth of an electrode for biodiesel synthesis were evaluated. The results show that cathodic plasma gave the highest yield of 98.76% and the lowest specific energy consumption of 720 J/ml. Meanwhile, under the same conditions, the anodic plasma gave the highest yield of 96.09% and the lowest specific energy consumption of 910 J/ml. These results indicate that cathodic plasma is better than anodic plasma in synthesizing biodiesel because it gives higher yield and lowers specific energy consumption.
Conversion of rubber seed oil into biodiesel with potassium oxide alumina supported by (K2O/Al2O3) catalyst
Authors: Karo Karo J A , Husin H , Nasution F , Yani F T , Maliki S , Prayuda D D , Hasfita F 
Published: January 2021

Abstract
In this paper, we report the synthesis of K2O/Al2O3 for its application as a catalyst in the transesterification reaction for biodiesel production from rubber seed oil. So far, biodiesel production has been done through transesterification of vegetable oils through homogeneous catalysts, such as NaOH and KOH. Heterogeneous catalysts are more advantageous because they are easy to separate from the products, have less corrosion, and can be reused. This study aims to investigate the effectiveness of potassium oxide alumina-supported (K2O/Al2O3) solid catalysts to convert rubber seed oil into biodiesel. The K2O/Al2O3 catalyst was synthesized by impregnating KOH on the support of Al2O3 through the inception wetness method. The catalysts were characterized by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX) to detect surface structure, composition, and active phase of the catalyst. EDX analysis indicated that the catalyst consisted of 36.41% potassium, 32.89%, and 30.7% oxygen. The reaction was conducted in a two-neck glass reactor at a temperature of 65°C, methanol to oil ratios of 10:1, during 1.5 h. The yield of biodiesel was achieved up to 96.9% at the ratio KOH: Al2O3 of 7.5: 2.5.
Performance and engine exhaust emissions in a mixture of pertamax with PET plastic oil
Authors: Winangun K , Putra W T , Buntoro G A , Nirmala A , Puspitasari I 
Published: January 2021

AbstractPublic knowledge about plastic waste management is still a major problem. This study aims to determine the performance and engine emissions of a mixture of pet (p) and Pertamax (b) plastic oil, the purpose of which is to increase the RON of plastic oil. There were 3 fuels tested, pure plastic oil (p100), 90% Pertamax + 10% plastic oil (bp10), 80% Pertamax + 20% plastic oil (bp20). The highest torque test result was 11.38 nm at p100, the highest power was at bp20 with a value of 8.24 hp. exhaust gas emissions of CO = 4.33% at p100, and the best O2at 6.43% at rpm of 8500 with a mixture of bp20 fuel.
The kinetic study of pyrolysis of lignite and polyethylene plastic bag waste using the thermogravimetric analysis
Authors: Aulia N , Wijayanti H , Wicakso D R 
Published: January 2021

Abstract
Lignite or low rank coal has a great potential to be utilized as an alternative energy. In this study, the pyrolysis of lignite and polyethylene plastic bag waste with different compositions (0, 25, 50 and 75 wt.% of polyethylene) had been investigated using a thermogravimetric analyzer. The results showed that the decomposition temperature of lignite was in the range of 250-600°C, while the decomposition temperature of lignite-polyethylene plastic bag waste mixtures was around 280-600°C. The addition of polyethylene to the lignite during pyrolysis reaction contributed to the increasing mass decomposition from 32.16 wt.% (lignite only or 0 wt.% of polyethylene) to 72.70 wt.% (75 wt.% of polyethylene). Furthermore, the thermogravimetric data were used to perform the kinetic study. The obtained kinetic parameters (activation energy and pre-exponential factor) for both lignite and lignite-polyethylene plastic bag waste mixtures were in the range of 16.16-28.95 kJ/mol and 0.014-0.212 min-1.
Increasing product quality of torrefied palm kernel shell batch model with internal surface area modification
Authors: Karelius K , Dirgantara M , Rumbang N , Kristian N , Purwanto F 
Published: January 2021

Abstract
As the largest palm oil-producing country in the world, Indonesia has abundant biomass potential from the production of crude palm oil (CPO). Palm oil production in 2018 in Indonesia is 34.94 million tons, where have by-products are empty bunches (23%), mesocarp fiber (12%), and palm kernel shell (5%). Palm kernel shells are a potential biomass that can upgrade the quality as a solid fuel through thermochemical processes. Torrefaction is one of the thermochemical processes where currently being used to increase the quality of biomass. The usual method used for the torrefaction process in the laboratory is the batch method. However, this method has a disadvantage when the capacity is improved make decreases the quality of the fuel produced. In this study, the quality of torrefied palm kernel shell from batch and batch torrefaction with internal surface area modification were compared. The torrefaction process was carried out at 275°C, with a residence time of 30 minutes. The results showed that the torrefaction of the modified batch method had a better heating value, and was proximate as a fuel.
Optimization of the hydrogenation and rafination process for cocoa butter substitute production using palm kernel oil in a small and medium scale industry
Authors: Junaidi L , Lestari N , Meutia Y R 
Published: January 2021

Abstract
The study on the optimization of hydrogenation and rafination process for cocoa butter substitute (CBS) production using palm kernel oil in small and medium scale industry was conducted. The CBS production process included: hydrogenation, cooling, bleaching, filtering, deodorizing, cooling, and packaging. The optimum condition of the hydrogenation process was obtained using hydrogen with 0.2% nickel catalyst, at 195-200°C, under 2-2.5 bar, using 6.12 hz agitation at 1700 rpm, for 12 hours process. The optimum condition of the rafination process was achieved by bleaching using 2 % bentonite at 80-95°C for 45 minutes and cooling it at 60°C, and deodorizing it at 240°C for 4 hours. The final product of CBS had similar quality characteristics as commercial cocoa butter and was well accepted by consumers. It contained no trans-fatty-acid, 0 nickel, low FFA, and a melting point of 37.1°C.
Preparation of the NiCl2 intercalated on the bentonite as a catalyst in the cracking process of biodiesel
Authors: Sutapa I W , Amalia S , Rosmawaty  
Published: January 2021

Abstract
Biogasoline is a benign energy product that can be produced through the process of breaking down biodiesel. The purpose of this study is to produce biogasoline from cooking oil waste through the cracking process using NiCl2 intercalated as a catalyst. Initially, waste from cooking oil was converted into biodiesel through a process of esterification and transesterification. After biodiesel with carbon chain lengths of 16-20 was acquired, the cracking process to produce biogasoline that had carbon chain lengths of 4-12 with the aid of a catalyst was conducted. The bentonite intercalated NiCl2 catalyst was calcined at a temperature of 600°C for 2 hours, then characterized by XRD and SEM. The results of the diffractogram with XRD showed a peak around 2θ: 44.67° which was the peak of the Ni crystalline. The cracking process of biodiesel was carried out at a temperature of 450°C and 500°C then characterized using GC-MS. The chromatograms generated at a temperature of 450°C showed the presence of three compounds belonging to the faction of biogasoline they were methyl 6-hydroxycaproate (C7H14O3), 4-hydroxymethyl-1,3-dioxolane (C4H8O3), and methyl nonylate (C10H20O2).
The potentials of biochar from agricultural waste as a carrier material of biofertilizer for swamplands
Authors: Maftuah E , Saleh M , Pratiwi E 
Published: January 2021

Abstract
Biochar has pores suitable for microbial habitat, and it contains carbon which can be used as an energy source by microbes. The research aims to determine the potential of some biochar as a carrier of biological fertilizer for swamplands. The treatment given was the type of biochar (rice husk, coconut shell, and palm empty fruit bunches) and the microbial type ie decomposer, Phosphate Solubilizing Bacteria (PSB), N Fixing Bacteria, and a consortium microbial. The design used was a Factorial Complete Randomized Design, 3 replications. Biochar analysis included organic C, total N, pH, CEC, SiO2, ash content and water content. Calculation of microbial populations was done at 2, 6 and 10 weeks after inoculation. Biochar rice husks, oil palm empty fruit bunches and coconut shells were very effective as decomposer carrier material. The highest of population of N-fixing bacteria and PSB at 6 weeks after inoculation was in the biochar rice husk reached 0.33 x 106 cfu/g for N-fixing bacteria and 54.8 x 106 cfu/g for P solvent bacterial. Rice husk biochar can be used as a carrier material both for a single biofertilizer, as well as a consortium biofertilizer that consists of decomposer fungi, P solubilizing bacteria and N-fixing bacteria.
The utilization of agricultural waste as biochar for optimizing swampland: a review
Authors: Susilawati A , Maftuah E , Fahmi A 
Published: January 2021

AbstractThe utilization of agricultural waste as biochar is one way to manage agricultural waste to encourage swamps optimization. There is quite a lot of agricultural waste in Indonesia estimated to reach 10.7 t y−1, including rice-husks, cocoa pods, coconut-shells, oil palm shells, and corncobs. One of the management of agricultural waste is to make biochar from various sources of raw materials. This paper is intended to provide information about agricultural waste as biochar in agriculture to optimize swampland in Indonesia. The quality of biochar depends on raw materials, incinerator, combustion temperature, and the length of combustion. The application of biochar on agricultural land serves as a soil enhancer that can improve its chemical properties and soil physical properties. Improvements in the quality of the soil chemical and physical properties impact the availability of nutrients and water through the ability of biochar to retain nutrients and water. In the end, the addition of biochar has implications for increasing the productivity of food crops. In the future, it is expected that with the application of biochar, swamplands can increase productivity.
Water management and rice husk biochar application to solve acid sulfate soil problems to promote rice yield and reduce greenhouse gas emission
Authors: Yusuf W A , Mukhlis  
Published: January 2021

Abstract
The use of biochar for soil fertility improvement is gaining popularity due to its potential to improve soil quality and increase crop yield in swampland. Water management plays a key role in controlling various dynamic processes such as acidity production. The water management system in acid sulfate soil should have a proper leaching and flushing capacity of the oxidation product. When these soils are used for rice, we found that the most important constraints were (1) Acidity (which includes the combined effects of pH, Al toxicity, and P deficiency) and (2) Fe stress (which is due to the combined effects of Fe toxicity and deficiencies of other divalent cations such as calcium/Ca). The experiment was carried out to investigate the effects of water management and rice husk biochar and compost applied in combination (0,1% of each w/w, thus 0,1% compost + 1% rice husk biochar) on growth, the yield of rice and methane emission on acid sulfate soil. The Provision of 50% compost + 50% Biochar rice husk with washing water management every two weeks (P2) in acid sulfate soil could reduce methane emissions by up to 53.16% with the highest dried unhusked rice yield of 3.86 t/ha.
Utilization of lightweight brick waste as soils stabilizing agent
Authors: Arifin Y F , Kusworo A S 
Published: January 2021

Abstract
The utilization of lightweight bricks as building walls, including houses, is getting higher. Beside its many advantages, lightweight brick also has disadvantages. One of them is that the remaining pieces cannot be used for its primary function and become waste. In the field, this waste is used as a material to stabilize the soil. However, there are no tests that examine its effectiveness as a stabilizing agent, the percentage of its composition, and what soil can be stabilized. This research focuses on laboratory tests on the use of lightweight brick waste for soil stabilization. The types of soil used in this study were lateritic, organic and expansive soil. The soils and waste were mixed at percentages of 2%, 4%, 6%, 8%, and 10% by weight. Some tests, such as the Atterberg limit, Standard Proctor compaction, and unconfined compression tests were carried out to determine its effect on the soil. The results showed that lightweight brick waste reduced the liquid limit, plasticity index, and increased soils shear strength. Different types of soil produced different levels of influence. Moisture content in the mixtures was also found to affect the results of soil stabilization.
Activated carbon from Nypa (Nypa fruticans) leaves applied for the Fe and Mn removal
Authors: Syauqiah I , Elma M , Mailani D P , Pratiwi N 
Published: January 2021

Abstract
Nypa palm (Nypa fruticans) is a type of palm-shaped mangrove. A nypa leaf contains 28.9% cellulose so that it is possible to produce an activated carbon applied for heavy metal removal in the solution. Thus, this study aimed to remove Fe and Mn in the FeCl3 and MnCl2 solution using the activated carbon produced from nypa leaves. In the experimental procedure, 5 grams activated carbon from nypa leaves (the particles that could pass through 40, 80, and 120 mesh size and retained on the sizes of 50, 100, and 150 mesh) were added and undergone in a batch system (for 60 and 120 minutes). The concentrations of Fe and Mn in the solution were investigated using the Atomic Absorption Spectrophotometer (AAS). The results showed that there were significant decreases in the Fe and Mn concentrations at the 60-minutes contact time with 150 mesh particle size (the absorption capacity values of Fe and Mn were 59.96 and 96.94 wt.%, respectively). This was due to the bigger surface area of the adsorbent and the longer contact time resulting in better interaction between the activated carbon from nypa leaves to remove Fe and Mn concentrations in the solution.