bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Investigation of Double Stage Air Intake in Throat-less Downdraft Biomass Gasifier
Authors: Dafiqurrohman Hafif , Surjosatyo Adi , Anggriawan Muhammad Barryl
Published: November 2018

Indonesia has a huge potential rice husk waste of 150 GJ/year, a third more than the overall potential of biomass in Indonesia of 470 GJ/year. Gasification of small-scale biomass fixed bed downdraft becomes one of the best solutions to become energy for power and heat generation. From studies that have been conducted abroad and from previous studies, the use of double stage air intake on the reactor proved effective in reducing tar because tar formed from the pyrolysis zone must pass through two zones below before then out with the gas producer. Implementation of secondary air intake at position Z = 38 cm right on the pyrolysis zone, obtained results at ER 0.25. With the same size, as much as 80.82% with tar content on the producer gas of 11.62 grams/Nm3. While at ER 0.23 figures found the highest gasification efficiencvby 33.41%.
Solar panel performance analysis under indonesian tropic climate using sandia PV array performance model and five parameter performance model
Authors: Petrana Subhan , Setiawan Eko Adhi , Januardi Adi
Published: November 2018

Evaluation and monitoring of solar panel are need to be done, primarily related to how much energy is produced. Energy production by a solar panel is affected by the characteristics of climate or weather of a particular location such as solar radiation and ambient temperature. This study aimed to compare two models of solar panel performance calculation, i.e., Sandia PV Array Model and Five Parameter Model by considering the tropical climate of Indonesia and see the effect of temperature and solar radiation changes on the results of the calculations of both methods through the I-V curve. The types of solar panels on monitored are a monocrystalline, polycrystalline, and thin film. The results show that the energy produced by Sandia PV Array Performance Model for the three types of solar panels are 54.36 Wdc, 51.57 Wdc, and 39.62 Wdc, respectively. Five Parameter Performance Model results are 56.58 Wdc, 52.7 Wdc, and 43.29, respectively. These results show that with a small amount of data, the Five Parameter Model is more optimal and efficient for the tropics compared to Sandia PV Array Model.
Techno Economic Analysis Photovoltaic On-Grid System Java Bali to Optimize PLN Energy Consumption
Authors: Hernanda Ikhsan , Fairuz Riadhi , Setiawan Eko Adhi
Published: November 2018

Indonesia’s electricity needs are increasing along with population growth. Nonrenewable natural resources are insufficient for power generation. Indonesia as a country located on the equator, has 4.8 kWh/m2/day the potential of solar energy, it is time for expanded renewable energy based photovoltaic. The potential development of photovolitaic system in Java Bali is planned to 800 MW based on Rencana Usaha Penyediaan Tenaga Listrik (RUPTL) year 2018-2027. Photovoltaic system on-grid rooftop 2 kWp designed on the Java Bali residence sector based on income of population, number of customers, power sales, and number of population. The energy produced by photovoltaic on-grid system can save the use of coal fuel in 2019 of 1.07 trillion rupiah and until 2027 can save about 11.08 trillion rupiah. The net metering scheme with 30% incentive can be applied for photovoltaic on-grid rooftop 2 kWp system. Photovoltaic on-grid system in the residence sector in Java Bali can save electricity payment for 37.9-41%.
Boosting renewable power generation in Indonesia electricity sector: a policy action by the government
Authors: Sommeng Andy Noorsaman , Anditya Chrisnawan
Published: November 2018

Indonesia is committed to reducing Greenhouse Gas Emissions (GHG) by 29% against Business as Usual (BAU) projections in 2030 with its own efforts and 41% with international assistance as part of the Paris Agreement. In the management and utilization of electricity, the development of renewable energy (RE) power generation in Indonesia is carried out while taking into account the balance with other aspects, namely Energy Security, Energy Equity, and Energy Sustainability or called as Energy Trilemma. In accordance with PLN’s Electricity Supply and Demand Business Plan (RUPTL) 2018-2027 that has been approved by the Minister of Energy and Mineral Resources, the total capacity of RE power generation to be built up to 2025 is about of 14.3 GW consists of geothermal power generation (PLTP) of 4.6 GW; hydro power generation (including mini-hydro and pump storage): 7.7 GW; solar power generation (PLTS): 1.0 GW; wind power generation (PLTB): 0.6 GW; and biomass/waste power generation (PLTBm/PLTSa): 0.4 GW. The RE power generation to be developed is still dominated by "Non-Intermittent" RE power generation (89%). While the "Intermittent" RE power generation that will be developed is still relatively small, which is only about 11%. This is due to challenges in its development, namely PLN is the only "Off-Taker" in the electricity business, and not all RE power generation can be accepted by the electricity system. As an effort to improve the development of RE power generation, the policy actions that have been or will be implemented by the government are 1) Development of RE power generation should be consider the balancing between "supply and demand" and the readiness of the electricity system to tapping the RE power generation at the most competitive costs; 2) Development of Distributed Generation or Micro-Grid; 3) Revision of the Grid Code to accommodate the Intermittent RE power generator; 4) Development of Smart-Grid; and 5) Acceleration of the Electric Vehicle Program.
Flavonoid isolation and identification of mother-in-law’s tongue leaves (sansevieria trifasciata) and the inhibitory activities to xanthine oxidase enzyme
Authors: Abdullah  , Angelina  , Yumna Mauhibah , Arbianti Rita , Utami Tania Surya , Hermansyah Heri , Ningsih Sri
Published: November 2018

Hyperuricemia is a disease that is characterized by high uric acid levels, in which the number of victim increase year by year in the worldwide. Flavonoid is an active compound with inhibitory activity towards Xanthine Oxidase Enzyme which is a compound that plays a role in the formation of uric acid in the body.Sansevieria trifasciatais an ornamental plant which is also useful as a source of antibacterial and antioxidant agent. Studies of S.trifasciataas Xanthine Oxidase Enzyme inhibitor have not been reported. This research isolate flavonoid compounds using open column chromatography from crude extract of S.trifasciataleaves that extracted by sonication method. There are six eluent used to isolate flavonoid which are methanol : ethyl acetate, chloroform : ethyl acetate, chloroform : ethyl acetate : methanol. Wilstater test is used to select the fraction that rich of flavonoid. The best result from isolation step that contains flavonoid is assessed the inhibitory activity of xanthine oxidase. It is analyzed qualitative using Liquid Chromatography Mass Spectrometry (LCMS). The inhibition percentage showed that fraction 3 was potential to inhibit XO by 85.48 %. LC-MS chromatogram can show that crude extract and positive fraction of isolation were containing falvonoid.
The Effect of NADES Ratio Solvent and Sonication Time in Extraction of Papaya Sap for Bio-insecticide Production
Authors: Zikri M F , Tibrizi A , Marsino Y , Utami T S , Arbianti R , Hermansyah H
Published: November 2018

Along with the increasing quantity of agriculture in Indonesia, should be followed by improving the quality of agriculture. Generally one of the indicators or parameters commonly used to indicate the quality of agriculture is the number of pests that damage plants in certain areas. The control of disturbing organisms on the plant can be minimized by the bio-insecticide production of Carica papaya which is tapped and extracted with ultrasonic-assisted using a mixed NADES solvent from Cholin chloride (ChCl) and Oxalic acid (Ox) with varying sonification time for 10, 20, 30 minutes and solvent ratio of 1: 2 and 2: 1. Bio-insecticide was produced by conducting qualitative enzyme activity of with lowry method and quantitatively using UV / Vis spectrophotometer aid with 750 nm wavelength and efficacy test. The best extraction result was obtained at NADES solvent with 1: 2 ratio with extraction time for 30 min with extraction time for 30 minutes yielding protein concentration equal to 7,23 ppm and tyrosine concentration equal to 7,9 ppm. Bio-insecticide samples effectively kill grayak caterpillars with 100% mortality within 5-7 days.
Acid leaching and kinetics study of cobalt recovery from spent lithium-ion batteries with nitric acid
Authors: Yuliusman  , Fajaryanto Radifan , Nurqomariah Annisaa , Silvia
Published: November 2018

Relentless development of technology triggers the smartphone production. The increasing number of smartphone use is followed by escalation of its waste, where its battery is usually left unrecycled. The analysis of the battery content shows that it is consist of a considerable amount of cobalt that can be reutilized based on its relatively high economic value, which valued USD 61/kg. Leaching as a form of hydrometallurgy was used in this research to recover cobalt using HNO3 as leaching agent and H2O2 as reducing agent. Process optimization was done by varying concentration of nitric acid and reaction temperature. The result showed that the optimum leaching condition was earned in 30 minutes of leaching reaction using 3.0 M HNO3 at the reaction temperature of 90°C, resulting 98.01% of cobalt leaching efficiency. Reaction kinetics study was also done in this research and the result demonstrates that recovery of cobalt from spent lithium-ion battery by nitric acid leaching was controlled by diffusion through product layer with activation energy value of 44.67 kJ/mol.
Optimization of Fe2+ addition for degradation process of textile dye waste using contact glow discharge electrolysis with air injection
Authors: Sukreni Tulus , Amelinda Nadya Saarah , Saksono Nelson , Bismo Setijo
Published: November 2018

This research determined the optimum concentration of Fe2+ to degrade waste textile dye by Contact Glow Discharge Electrolysis (CGDE) method with air injection. The addition of Fe2+ ions can increase the degradation rate of the dye waste due to the radical catalytic conversion of H2O2 producing OH radicals that play a significant role in the degradation process. Remazol Red was used as a dye synthetic dye which was degraded using a batch reactor equipped with continuous cooling water. Experimental results showed that waste concentrations of 100, 200, 300 and 400 ppm obtained the optimum Fe2+ concentration at 10, 20, 30 and 40 ppm, respectively. The higher concentration of dye waste indicated the higher the Fe2+ ion requirement to decrease the textile dye waste.
The Effect of Compatibilizer Addition on Chlorella vulgaris Microalgae Utilization as a Mixture for Bioplastic
Authors: Dianursanti  , Khalis SA
Published: November 2018

Nowadays, plastic waste is the biggest environmental issues. Since the usage of conventional plastic which come from synthesis polymer that can not be decomposed by decomposer. One of the solution is bioplastic. This study used Chlorella vulgaris and PVA as the based materials to made bioplastic. Chlorella vulgaris is chosen as the new potential of raw material for its high amount of biopolymer (Protein, carbs). However, Chlorella/PVA has some weakness such as poor physical- chemical properties. Compatibilizer is needed to improve the homogeneity and compatibility of natural and synthetic mixtures as both materials have different properties. This study aims to obtain the best maleic anhydrates concentration as compatibilizer for PVA-Chlorella plastic based. Maleic anhydrate-grafted PVA (PVA-g-MAH) was synthesized by blending PVA, maleic anhydrate, DMSO and KPS with temperature 120°C. Chlorella was modified by mixing distillated water and glycerol. Both of them are mixed well then molding by temperature 120°C. The addition of maleic anhydrates concentration (2%, 4%, 5% wt of PVA) respectively improve surface structure and cause increasing in tensile strength from 31.27 to 42.25 kgf/cm2and also increasing elongation from 10.86 to 13.00 %. With this result, it can be indicated that compatibilizer addition can improve the homogeneity and elasticity the mixture of PVA-Chlorella plastic film.
The effect of glycerol addition as plasticizer in Spirulina platensis based bioplastic
Authors: Dianursanti  , Gozan Misri , Noviasari Citra
Published: November 2018

Bioplastic is one of the breakthroughs in the effort to reduce plastic waste. The bioplastic can be produced from microalgae with a high protein content, such as Spirulina platensis. The aim of this research was to produce S. platensis-based plastic with mechanical properties that mimics the commercial plastic bags. The microalgae were mixed with polyvinyl and maleic anhydride as compatibilizer to strengthen the bond between the microalgae and polymer. Glycerol was added as plasticizer to increase the flexibility. Observation was carried out on tensile strength and elongation of bioplastic with a variation of 15, 20, 25, and 30 wt% of glycerol content. The results show that the optimum plasticizer composition for this S. platensis-based bioplastic film was 30 wt%, which shows the tensile strength at 27.7 kgf/cm2 and elongation at 66%. The tensile strength was very close to that of commercial plastic bags. The elongation property should be improved in order to be utilized for plastic bags. However, this bioplastic is very suitable for food, pharmacy, and cosmetic packaging materials that do not need high elongation.
The effect of RAFT polymerization on the physical properties of thiamphenicol-imprinted polymer
Authors: Yusof Noor Fadilah , Mehamod Faizatul Shimal , Suah Faiz Bukhari Mohd
Published: November 2018

The necessity to overcome limitation of conventional free radical polymerization, technology has shifted the way to find an effective method for polymer synthesis, called controlled radical polymerization (CRP). One of the most studied controlled radical system is reversible addition-fragmentation chain transfer (RAFT) polymerization. The method relies on efficient chain-transfer processes which are mediated typically by thiocarbonyl-containing RAFT agents e.g., dithioesters. The presented study revealed the potential benefit in applying RAFT polymerization towards the synthesis of molecularly imprinted polymer for thiamphenicol. They were synthesized in monolithic form using methacrylic acid, ethylene glycol dimethacrylate, azobisisobutyronitrile and acetonitrile as a functional monomer, cross-linker, initiator and porogen, respectively. The surface morphology was studied by scanning electron microscopy (SEM), structural characterization by Fourier transformed infrared (FTIR) and pore structures of polymers produced were characterized by nitrogen sorption porosimetry. SEM analysis showed MIPs produced by RAFT have smoother surface while porosity analysis showed the specific surface area was slightly larger compared to conventional polymerization methods. However FTIR showed the same pattern of spectra produced due to the same co-monomers used in the production. The results upon the uses of RAFT polymerization enables the production of imprinted polymers enhanced the physical properties compared to conventional polymerization.
The effect of addition of sodium sulphate (Na2SO4) to nickel slag pyrometallurgical process with temperature and additives ratio as variables
Authors: Patrick Juan , Prasetyo Agus Budi , Munir Badrul , Maksum Ahmad , Soedarsono Johny Wahyuadi
Published: November 2018

Nickel industry is one of the most strategic industries because its widely used. Nickel slag as a by-product of nickel processing presents the potential for improving process efficiency. In this study aim to determine the effect of the addition of sodium sulfate additives and also the temperature in the reduction process of nickel slag. The research was preceded by preparation of nickel slag samples with crushing and sieving up to 200 mesh. The nickel slag is then reduced at 800°C, 900°C and 1000°C temperature without adding sodium sulfate and by adding sodium sulfate with 1 hour holding time. Furthermore, the results of the reduction is done XRD and AAS testing to see changes in the content of elements and compounds in nickel slag that has been tested. The results of the study explain that the content of the dominant impurities which is in the form of SiO2 decreases as the temperature of the reduction and iron from Fe-rich Forsterite compounds will be liberated and will bind to sulfur derived from sodium sulfate to form troilite (FeS). This results in an increasing content of valuable minerals present in the nickel slag.
Effect of Coagulant Dosage on Tofu Industry Wastewater Treatment in Combination with Ultrafiltration Process using Polysulfone Membrane
Authors: Oktariany Aditha , Kartohardjono Sutrasno
Published: November 2018

Wastewater from tofu industry is one of water pollution sources that still require more effective treatment. This study aim to treat wastewater from tofu industry through a combination of coagulation-flocculation and ultrafiltration processes. Coagulation-flocculation is conducted prior to ultrafiltration process to minimize the effect of fouling on membrane and to improve the performance of ultrafiltration process. Poly aluminum chloride (PAC) was used as coagulant with doses of 100, 200, 300, 400 and 500 ppm. The wastewater feed have pH, total dissolved solid (TDS), total suspended solids (TSS), turbidity and chemical oxygen demand in the ranges of 3.8 - 4, 850 - 880 mg /L, 380 - 420 mg /L, 450-530 FAU and 5600 - 6600 mg /L, respectively. Experimental results showed that the effectiveness of coagulation increased with the addition of coagulant dose until the optimum dose is reached. After coagulation-flocculation process, COD, TSS, and turbidity decreased, whereas TDS increased. The optimum dose of the coagulationflocculation process was then used for a combination of coagulation-flocculation and ultrafiltration processes. The result of this combination process showed a decrease in COD, BOD, TSS, and turbidity.
Effect of pH of Coagulant on the Treatment of Wastewater from Tofu Industry
Authors: Aditya Irfan , Kartohardjono Sutrasno
Published: November 2018

Wastewater generated from the tofu industry usually still contains high organic pollutants that can contaminate the surface water. Therefore, it should be treated properly before it can be disposed to the environment. This study aims to evaluate the combination of coagulationflocculation and ultrafiltration methods in treating the wastewater from tofu industry. Based on the preliminary tests, the wastewater from tofu industry have pH, total dissolved solid (TDS), total suspended solid (TSS), turbidity and chemical oxygen demand (COD) of 3.4, 870 - 1080 mg/L, 370 mg/L, 446 FAU and 7954 mg/L, respectively. The coagulant and membrane used in this study were Poly aluminum chloride (PAC) and the ceramic membrane, respectively. Experimental results showed that the best pH for coagulation-flocculation process is at pH of 7.0, and this pH was then used for ultrafiltration process. The flux of the ultrafiltration membrane increased with increasing the trans membrane pressure due to increasing driving force. The observed parameters such as TSS and turbidity of wastewater decreased drastically after experiencing ultrafiltration process and met the National Environmental Quality Standard. However, the COD of water produced in the ultrafiltration process was still high and did not meet the National Environmental Quality Standard.
Aquadest Production System as Steam Turbine Bottom Cycle I: Influence of Pressure of Cooling Water Tank and Pinch Point Temperature Difference of Condenser
Authors: Achmad Kosasih Engkos , Alfan Farizi Ahmad , Ibnu Wahid Rizal
Published: November 2018

The condenser heat from the steam turbine system is discharged into the environment in a way that is likely to damage the environment. This paper simulates a system that produces aquadest with throttled 10% water of condenser output to the cooling water tank with vacuum pressure so as to produce water vapor. This water vapor is condensed in a cooling machine to produce aquadest. The cold water coming out of the cooling water tank is mixed with cooling water from the sea so the temperature is lower causing the condenser output water to be lower temperature (more environmentally friendly). This simulation varies the pressure of cooling water tanks and Pinch Points Temperature Difference (PPTD) of condenser. From the simulation it is found that the higher the pressure of the cooling water tank causes Specific Aquadest Production (SAP), and Energy Consumtion (EC) is getting smaller. The smaller PPTD leads to Specific Aquadest Production (SAP), Specific Energy Consumtion (SEC) and Energy Consumtion (EC) getting smaller. This simulation has the best result that is able to produce aquadest as much as 0.0133 [kg/s], increase the efficiency of steam power plant by 0.21%, and lower condenser water temperature by 0.9 °C.
Propulsion System Analysis For Solar-Powered Electric Water Recreational
Authors: Sunaryo  , Nurachman Dendi
Published: November 2018

Indonesia is the world’s largest archipelago with more than 17,000 islands, and also the best marine tourism destination, there are many beautiful beaches and underwater spots throughout the country. Due to this potential condition Indonesian government is planning to improve its maritime tourism sector. To realize this boats play very important role both for transport as well as for recreational purposes. On the other hand the government is also committed to reduce the global warming from the use of fossil fuel especially in industry and transportation through the Presidential Regulation no. 61/2011, with the strategy for replacing the fossil fuel with renewable energy. To support the government’s program the research is aimed to design solar-powered electric recreation boat for tourism, with the consideration that there is almost non-stop sun shine available all year long in Indonesia. The boat has length of 12 meters. In this paper the focus is on the analysis of the propulsion system of the boat, which consists of the calculation the power needed to run the electric motor, the optimum propeller design, and the steering system.
Characterization of cellulose acetate based on empty fruit bunches and dried jackfruit leaves as replacement candidates for microbeads
Authors: Tristantini Dewi , Yunan Andersen
Published: November 2018

Scrubs used in other skin care and beauty products usually contain tiny fine grains of synthetic polymer called microbeads that usually pose threats to marine environment. Empty Fruit Bunches (EFB) and Dried Jackfruit Leaves (DJL) as organic and environmentally friendly can be alternative sources for polymer microbeads. Cellulose acetate is prepared by acetylation reaction between cellulose and acetic acid anhydride. Cellulose from EFB and DJL was extracted through a process of delignification with 12% NaOH treatment for EFB and 10% for DJL to obtain maximum yields of 38.964% and 14.449% respectively, followed by bleaching using peroxide 10 %. The formed cellulose acetate with 88.5% and 79.7% yield respectively is then filtered using a sieve mash 60 and 80 to obtain particle sizes ranging that are in the microbeads size range. The density test resulting in 0.73 g/cm3 and 0.52 g/cm3 respectively for EFB and DJL. Then, physical characteristic test was done by water and oil absorption test with variation at 25°C and 40°C. EFB at 25°C and 40°C shows water absorption at 23.39% and 26.09% and oil absorption at 7.59% and 13.95%. DJL at 25°C and 40°C shows water absorption at 22.56% and 27.32% and oil absorption at 13.09% and 15.36%.
Absorber Thickness Effect on The Effectiveness of Solar Collectors to Production Hot Air For Drying
Authors: Syuhada Ahmad , Maulana Muhammad Ilham
Published: November 2018

One way to increase the drying rate using a solar collector is to increase the air temperature of the collector and the time of circulation of hot air delivered to the drying chamber. The optimization of heat absorber by utilizing solar energy has been shown to be strongly influence by fluid flow characteristics in the collector channel. This study examined the sharp turning channel on the air passage of a solar collector. Collector size used was 305 cm x 80 cm and had 10 sharp turning channel baffles. Solar radiation absorbent material used in this collector test is iron sand with three thickness variations, namely 3, 6, and 9 cm. The measurement results show that the air temperature that can be produced by the collector with a thickness of 3 cm absorber reaches 85 degree Celsius with an effective drying time of 8 hours and the final air temperature testing on the collector out side still reaches about 40 degree Celsius at air temperature of 32 degree Celsius. At a thickness of 6 cm absorber, the air temperature inside the collector was about 83 degrees and the duration of 10 hours of drying time, with the collector-out air temperature around 39 degree Celsius at the air temperature of 30 degree Celsius. In contrast to the 9 cm thickness of the absorber, the drying air temperature was only 81 degree Celsius and the drying time was 12 hours and the final air temperature measurement was 40 degree Celsius at the ambient temperature was 27 degree Celsius. This result can be seen as the effect of thick collector absorber on solar thermal energy that can also be absorbed by absorber solar collector.
Study of cryogenic power generation application at LNG regasification terminal
Authors: Prabowo Adhicahyo , Kartohardjono Sutrasno
Published: November 2018

Cryogenic Power Generation or commonly called Cryopower is the generation of electricity by utilizing cold energy which one is produced at the LNG (liquefied natural gas) Regasification Terminal. Cold energy utilization has been applied in several countries, especially in Japan. In Indonesia, the regasification terminal has been built few, but in the future according to the Government of Indonesia's plan, some natural gas/LNG power plants will be built to meet the national electricity needs. It requires gas infrastructure, one of which is the regasification terminal. The aim of this study is to evaluate the effects of LNG flowrate on working fluid and cooling water flowrates as well as power needed and produced in the combine direct expansion and Rankine cycle processes. The flowrates and power calculations were conducted using UNISIM R390.1. Simulation results showed that the working fluid and cooling water flowrates increase with increasing LNG flowrate. The increased in the working fluid and cooling water flowrates also increased the power needed by the pumps and power produced by the turbines. Overall, the net power produced from the combine cycle increased with increasing the LNG flowrate.
Synthesis of cellulose acetate from palm oil bunches and dried jackfruit leaves
Authors: Tristantini Dewi , Sandra Cindy
Published: November 2018

Cellulose acetate is a natural polymer, that is widely used in various industries, especially fiber and plastics. Cellulose acetate was created by an esterification reaction of cellulose and acetic anhydride. The raw materials used in this research were empty fruit bunches of palm oil and dried jackfruit leaves, because utilization of waste, available in large quantities, and contain high cellulose. The objective of this study was to obtain high yield cellulose and cellulose acetate from palm oil bunches and jackfruit leaves. This was done by variating delignification time, bleaching time, and acetylation time. Cellulose isolation was performed through a delignification process by adding NaOH and bleaching process by adding H2O2. The optimum yield for the empty palm oil bunches cellulose was 36.45%, with the delignification time of 1.5 hours and the bleaching time of 30 minutes. The optimum yield of jackfruit leaves cellulose was 13.72%, with 1-hour delignification time and 30 minutes bleaching time. Cellulose acetate was obtained by cellulose activation process by adding acetic acid glacial, acetylation process with anhydrous acetate, and hydrolysis with water. The yield of cellulose acetate obtained was 81.75% for palm oil bunches and 63.89 for jackfruit leaves.
Advanced characterization of microbeads replacement from cellulose acetate based on empty fruit bunches and dried jackfruit leaves
Authors: Tristantini Dewi , Yunan Andersen
Published: November 2018

The existing polymer microbeads for skin extraction ingredients have many disadvantages in environment. The application of cellulose has been proven in the pharmaceutical field in the form of beads on drug release can be a substitute alternative to polymer microbeads that will be prohibited. Based on several criteria and past researches, cellulose acetate meets the criteria for microbeads replacement. Cellulose is available in large quantities in the world, and many studies has proven its application on a wide scope. Empty Fruit Bunches (EFB) and Dried Jackfruit Leaves (DJL) are widely distributed raw materials in Indonesia so that they can be used as a substitute for microbeads. The FTIR and SEM-EDX tests were conducted to determine the functional groups of cellulose acetate and morphology formation of cellulose acetate both raw materials and their chemical composition. In FTIR testing, the typical absorption of EFB and DJL cellulose acetate is produced by C=O groups for EFB at wavelength 1721,36 cm-1 and DJL at wavelength 1725,22 cm-1, whereas at SEM-EDX, DJL cellulose acetate asymmetrical cylinders and rare small pores on the surface and cellulose acetate TKKS cylindrical symmetrical with small pores on its surface. The chemical components of EFB and DJL cellulose acetate exhibit organic elements of carbon (C) and oxygen (O).
Research on Energy Efficiency of Typical Construction Equipment for Transmission Lines in Tibet
Authors: Yongjun XIA , Fei ZHAO
Published: November 2018

The construction of transmission line in Tibet high altitude area has the characteristics of low pressure, low oxygen and low temperature. In the special environmental condition, the transmission line construction equipment with engine as the power source is highly effective, which affects the efficiency and safety of construction[1].The experimental study on engineering mechanical industry plateau transmission line is still in the blank stage,thus relying on the Tibet networking project selects 5 different high altitude test points to plateau 500kV transmission line construction commonly used types of pullers, tensioners and powered winch as an object of study to carry out the typical construction equipment energy efficiency test of field measurements effective output power equipment in different altitude environment from the perspective of practical application and analysis of law and effect mechanism of falling equipment.
Study on Deformation Behavior of Ti6Al4V Parts Fabricated by Selective Laser Melting
Authors: Yang Tao , Liu Tingting , Liao Wenhe , Zhang Changdong , Duan Shengqin , Chen Xiangyuan
Published: November 2018

During the Selective laser melting process, the accumulation of the residual stress caused by the excessive temperature gradients and the rapid solidification is the main factor causing deformation; and the wetting quality of the meltpool also has an impact. How to control the deformation is the key problem to improve the quality of the parts. In this paper, the thin-wall specimens are divided into four distinct conditions, analyzing the meltpool date collected by the melting pool monitoring system and the simulation of temperature field, the relationship between the process parameters and the deformation under the same energy density is discussed. The results show that the temperature, the width and the intensity of the meltpool increase with the increasing of the laser power and the scanning speed, but the temperature gradients and the rate of the solidification of the meltpool are on the contrary, resulting in the decrease of the residual stress and the deformation of the part, which is help to improve the quality of the part.
Research and Application on the Key Parameters of the Long Compression and Short Pumping Ventilation Dust Removal System
Authors: She-ji Zhang , Wei MA , Jin-ming MO
Published: November 2018

For the question of circulation wind emerged in the process of using long compression and short pumping ventilation dust removal system, a new model of air volume matching was proposed, and the empirical formula of the key process parameters such as axial and radial air volume, axial and radial air out distance were derived according to the relevant theories of air jet in the confined space. Then the 20106 return roadway of fully mechanized working face in Wang Jia Ling coal mine was selected to conduct field verification tests. The result showed that the new air volume catching model had good adaptability, and the key process parameters obtained by theoretical calculation and field test were basically identical. Under the condition of optimum technological parameters, the total dust and respiratory dust concentration of the driver’s place can be reduced 91.98% and 89.53% respectively.
Study of Plantar Pressure Distribution
Authors: Ang Chun Kit , Solihin Mahmud Iwan , Chan Weng Jun , Ong Yien Yien
Published: November 2018

Every region of foot is not equally divided in terms of plantar pressure distribution (PPD) during free standing. This paper is focusing on studying PPD on flat plane and inclined plane and the results obtained from this study may contribute to biomedical researcher in designing orthotic devices. 24 healthy young adults age ranging from 19 to 24 years old and weigh between 50 to 80 kg were invited for experiments purpose. Six regions of both feet were measured which were hallux, medial forefoot, central forefoot, lateral forefoot, lateral midfoot and hindfoot. Remarkable differences were seen in the result as right foot exerted more pressure generally in every region of the foot as to compared with left foot respectively. This is true especially for region such as hallux, medial forefoot and lateral forefoot. On a flat surface, PPD on the hindfoot is the highest. However, at an elevation of 25°, test subjects began to shift their PPD to forefoot regions. While studies of PPD are common, this study provides a new insight for the first time into PPD while standing on different angle of walking plane.
Swelling Properties of Propranolol HCl-loaded Polyvinyl Alcohol-graft-lactic Acid Hydrogel Films
Authors: Suksaeree Jirapornchai , Chuchote Chomnapas
Published: November 2018

This paper presented the swelling properties of propranolol HCl-loaded polyvinyl alcohol-graft-lactic acid (PPH-loaded PVA-g-LA) hydrogel films. The swelling properties including swelling-deswelling measurement and swelling behaviour in different environmental stimuli fluids such as water, various pH, and various ionic strength were determined. It was found that the swelling properties of the PPH-loaded PVA-g-LA hydrogel films depend on the LA amount addition. They had a good swelling and deswelling in water and acetone. The PPH-loaded PVA-g-LA hydrogel films showed the high swelling in the medium pH 7. Thus, the prepared PPH-loaded PVA-g-LA hydrogel films had a good swelling property that could be used to controlled drug release in pharmaceutical product.
Innovative Multilayer Polymer-glass Composites Reinforced with Metal-ceramic Foam
Authors: Gawdzińska Katarzyna , Grabian Janusz , Nagolska Dorota , Kwiecińska Barbara
Published: November 2018

When selecting the materials used in transport, in addition to the set of strength properties, which form the basis of the structural calculations, the possibility of weight reduction and the limitation of fire risks and maintenance activities should also be taken into account. The article provides a short description of both metal and metal-ceramic foams, as well as studies on multilayer sandwich composite materials. They consist of polyester-glass laminates and composite-ceramic foams. These materials were subjected to a technological three-point bending test. Such materials can replace the polyester-glass laminates that are commonly used in maritime transport and other industries.
Computational Thermal Model of Unidirectional Composites with Random Fiber Array
Authors: Zhang Yuxuan , Wang Hui , Lin Wanqing
Published: November 2018

The purpose of this work was to study the influence of microstructure on effective transverse thermal behavior of unidirectional fiber reinforced composites. Three types of microstructures are taken into account, including square periodic, hexagonal periodic and random arrangements of circular fibers. Unlike classical results at low fiber volume fractions and low thermal conductivity contrast between fibers and matrices, results provided by finite elements simulations for copper matrix composite reinforced with Carbon T-300 fibers have shown that random microstructures strongly affect the effective thermal properties of unidirectional composites for both high volume fractions and thermal conductivity contrast and can give closer predictions to the experimental results than the regular microstructures and the theoretical model.
Effects of Dopant Types and Contents on Morphology and Strength Properties of PANI/PAN Electrospun Nanofibers
Authors: Yan Taohai , Jiang Jinhua , Chen Nanliang
Published: November 2018

In this paper, the electrospinning of polyaniline under different dopant conditions were studied, the experimental phenomena was introduced, analyzed the relationship between the nanofiber surface morphology of DBSA-PANI/PAN, HCl-PANI/PAN and PTSA-PANI/PAN membranes and dopant type and content. The average diameter of DBSA-PANI/PAN electrospinning fiber membrane showed a decreasing trend when the content of doped polyaniline increased 1%-4%, and reached a minimum value of 780nm when the concentration was 4%. The strength of DBSA-PANI/PAN fiber membrane was the highest when the concentration of doped polyaniline was 1%, and the maximum intensity was 1.8×10 5 Pa. The average diameter of HCl/PANI/PAN fiber membranes decreases with the increase of doped polyaniline concentration, and it fluctuates up and down within a small range. When the content of doped polyaniline was increased to 4%, the average fiber diameter reached a minimum of 420 nm. The strength of the HCl-PANI/PAN fiber membrane was the highest when the concentration of doped polyaniline was 4%, and the maximum intensity was 1.08×10 5 Pa. The average diameter of the PTSA-PANI/PAN electrospun fiber membrane was the smallest at 2% doped polyaniline content and was 430 nm, the strength of PTSA-PANI/PAN fiber membrane is the highest when the content of doped polyaniline is 2%, and the maximum intensity is 3.9×10 4 Pa. In this paper, the basic research of doped polyaniline electrospinning nanofibers has made a useful supplement to the existing research of polyaniline nanofibers, and has a reference value for the application of polyaniline.
Designing Service Blueprint of Self-service Technology (SST) Based Public Transportation Service in Indonesia using SSTQual, Kano Model, and QFD
Authors: Suzianti Amalia , Chairunnisa Arsila
Published: November 2018

Indonesia as one of developing countries has started to slowly implement self-service technology to its public transportation services which are e-ticketing and e-gate. Regardless of the public’s enthusiasm for these self-service technologies implemented, users’ complaints regarding the services implies the importance to redesign services that are focused on user satisfaction. This study attempts to result a design recommendation method for self-service technology based public transportation service to improve customer satisfaction by integrating SSTQual method, Kano Model, QFD and service blueprinting. Result shows that there are 12 service attributes belong to attractive category which need to be prioritized in increasing customer satisfaction. 12 attributes are then translated into technical requirements to obtain innovations to be used in the service blueprint. Through this research, there are 10 technical requirements which need to be applied to improve customer satisfaction. The technical requirements are then detailed in operational actions to be mapped in the service blueprint.
Innovation Design and Empirical Research Based on Presentation of Lumbar Muscle Strain and Sanitation Products
Authors: Chen Ran , Chen Ming , Lyu Jian-hua
Published: November 2018

This article takes the lumbar muscles of degeneration status of Chinese sanitation workers as the starting point, analyzed the waist health status of sanitation workers in China. The design conception of sanitation products for the lumbar muscles of degeneration of sanitation workers was obtained by analysis, and the design of today's sanitation products are rethought, use relevant research results to demonstrate that. With sanitation products as the design center, it integrates many research contents such as ergonomics, appearance, function, process and cost. To this article has designed tools that sanitation workers can use to protect their waists while working, It also provides a new idea for the wide design of sanitation products. It is conducive to maintaining the basic rights and interests of sanitation workers and promoting the urbanization process and the harmonious development of society.
Preparation of ultrafine iron phosphate micro-powder from phosphate slag
Authors: Sun Fangjing , Zhang Yi , Zhang Jiawei , Yan Xixi , Liu Xiaoyu , Wang Lijun
Published: November 2018

In this experiment, ultrafine iron phosphate micro-powder was prepared by hydrothermal method which used phosphate slag as an iron source. The effects of reaction temperature, surfactants type and amount on its particle size were explored. The samples were characterized by using Malvern Laser Particle Size Analyzer (MS2000), X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive X-Ray Spectroscopy (EDX).The results showed that at 160 °C, 1 wt%CTAB, monoclinic iron phosphate micro-powder was obtained with an average particle size about 0.4 μm which also has a good dispersion in aqueous solution.
Study on reaction mechanisms of iron matrix compositesreinforced with in situ Al2O3 particles reacted byAl-Fe2O3-Fe system
Authors: Zhu Chengyan , Jiang Jie , Zhu Heguo
Published: November 2018

Iron matrix composites reinforced with Al2O3 particles were fabricated in situ through exothermic dispersive (XD) reaction from a powder mix of pure elements Fe, Al and Fe2O3. The fabrication and reaction mechanisms were investigated by using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS) and differential scanning calorimetry (DSC) analysis. The reaction between Al and Fe2O3 was found to occur in three steps. Their activation energies are 203.8 kJ/mol, 1100.9 kJ/mol and 380 kJ/mol, respectively. DSC analysis shows that the reaction peak shifts to a higher temperature with an increase in the heating rate. When the heating rate is 10 K/min, the rates of the three reactions exhibit a similar trend, i.e., the reaction rate is very slow at the start, and then it increases rapidly, finally it becomes slow again. Their reaction times are 456, 672 and 650 s, respectively.
Relationship between Anti-frozen Durability and Pore Structure on Concrete in Freeze and Thaw Cycle Environment
Authors: Wang Chao , Liu Zhao-Lei , Yu Lei
Published: November 2018

To detect which micro structure index can make an effected on the anti-frozen durability on concrete, 3 kinds of concrete with different mix proportion have been made. The dynamic modulus of elasticity and pore structure index were detected and the relativity of them was analysed. The result shows that the dynamic modulus of elasticity decreases after freezing and wary with porosity. Critical pore size becomes larger. The gel pore amount decreases. The capillary and macro pore amount increase. There is a good relativity between frost-resistance performance and pore parameters. By decreasing porosity and the amount of macro pore, increasing gel pore amount, the anti-frozen durability can be enhanced.
The low infrared emissivity of Ce1-xYxO2-x/2 samples at high-temperature contributed by enhanced conductivity
Authors: Bu Honghan , Liu Chuyang , Xu Guoyue , Jiang Yong , Guo Tengchao , Zhang Jianchao
Published: November 2018

The Ce1-xYxO2-x/2 samples were synthesized with different doping amount by solid state reaction method. Phase structures of the samples were analyzed and characterized by XRD. The effects of different doping amount on infrared emissivity properties at 3-5µm wavebands were investigated systematically. It is found that the powder with doping molality of x=0.2 exhibits the lowest infrared emissivity value ca. 0.21 when the test temperature is 600 °C. The mechanism for the low infrared emissivity is explored thoroughly. The reduction of infrared emissivity with increasing temperature is ascribed to the enhancement of electrical conductivity. Our results suggest that Ce1-xYxO2-x/2 powder with x=0.2 is a potential candidate for stealth material of aircraft engines.
Visible light Bi2S3/BiFeO3 photocatalyst for effective removal of Rhodamine B
Authors: Wang Xiquan , Zhang Nan , Wang Gao
Published: November 2018

Bi2S3-sensitized BiFO3 (BFO) photocatalyst (Bi2S3/BFO) was successfully synthesized through a facile and environmental ion exchange method between BFO and Thiosurea (H2NCSNH2, TU). The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and UV-vis diffuse reflection spectroscopy (DRS). The obtained Bi2S3/BFO composites showed excellent photocatalytic performance for decomposing Rhodamine B (RhB) compared with pure BFO under visible light irradiation (λ>400nm). 5% Bi2S3/BFO exhibited the highest photocatalytic activity and excessive amount of Bi2S3 would result in the decrease of photocatalytic activity of BFO. The mechanism of enhanced photocatalytic activity was proposed on the basis of the calculated energy band positions.
Fabrication of Co3+ and B co-doping BiVO4 with improved photocatalytic performance for organic degradation
Authors: Li Zhilin , Jin Chongyue , Wang Min
Published: November 2018

Co3+ and B co-doping BiVO4 photocatalysts were successfully prepared for organic pollutants degradation through sol-gel and impregnation two-step process. Their structure, surface chemical composition, and optical absorption were characterized. All as-prepared samples consisted of the monoclinic phase. It was found that the Co dopants was existed in the form of CO3O4 in B-BiVO4, thus a p-n heterojunction formed in BiVO4. The optical absorption results reveal that Co3O4 could greatly enhance the absorption and decrease in the band-gap energy of BiVO4. The 0.5% Co3+ doping B-BiVO4 sample exhited the highest photocatalytic activity for methyl orange photocatalytic degradation, being approximately 92% of MO degradation rate under 50 min visible light irradiation.
Research on the Steel for Oil and Gas Pipelines in Sour Environment
Authors: Shao Xiaodong
Published: November 2018

In recent years, there are more and more oil and gas fields containing H2S corrosive media, and it is imperative to develop oil and gas transmission pipes in acidic environment. The research progress of steel for oil and gas pipelines in acidic environment is reviewed from the aspects of H2S corrosion mechanism and influencing factors in pipeline service under acidic service conditions. At the same time, the development status of sour-resistance corrosion oil and gas transmission steel tubes at home and abroad is introduced. Pipeline steel is further explored in terms of SSCC-resistance research and improvement of corresponding standards.