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"The gas diffusion layer (GDL) is one of the critical components of a proton exchange membrane fuel cell (PEMFC). It is generally made of a fossil-fuel-based carbon material. In this study, carbon composite paper (CCP) for GDL was prepared by using carbon material obtained from coconut coir. To obtain the CCP, 80 wt% carbon material from the coconut coir and 20 wt% polymer binder (ethylene vinyl acetate and polyethylene glycol) were mixed in xylene solvent at 100°C, cast on molded glass, and then rolled. The carbon material consists of a mixture of carbon fibers (length: 2 mm) and powders (size: 74 µm). Subsequently, the CCP was treated with polytetrafluoroethylene solution (10 wt%). The physical properties of the CCPs, such as through-plane electrical conductivity, porosity, density, and hydrophobic properties, were investigated. Scanning electron microscopy and energy-dispersive spectroscopy mapping were used to analyze the morphology and polytetrafluoroethylene (PTFE) distribution in the CCP. The through-plane conductivity test showed that CCP with 70 wt% carbon fiber, 10 wt% carbon powder, and 20 wt% polymer was the optimum sample, and it showed the highest electrical conductivity of 2.22 S cm-1. The physical properties of PTFE-treated CCP, such as porosity, density, and contact angle, were almost similar to that of commercial carbon paper used as a GDL. Therefore, the CCP prepared from coconut coir can be applied as a GDL in a PEMFC."

"The gas diffusion layer (GDL) is one of the critical components of a proton exchange membrane fuel cell (PEMFC). It is generally made of a fossil-fuel-based carbon material. In this study, carbon composite paper (CCP) for GDL was prepared by using carbon material obtained from coconut coir. To obtain the CCP, 80 wt% carbon material from the coconut coir and 20 wt% polymer binder (ethylene vinyl acetate and polyethylene glycol) were mixed in xylene solvent at 100°C, cast on molded glass, and then rolled. The carbon material consists of a mixture of carbon fibers (length: 2 mm) and powders (size: 74 µm). Subsequently, the CCP was treated with polytetrafluoroethylene solution (10 wt%). The physical properties of the CCPs, such as through-plane electrical conductivity, porosity, density, and hydrophobic properties, were investigated. Scanning electron microscopy and energy-dispersive spectroscopy mapping were used to analyze the morphology and polytetrafluoroethylene (PTFE) distribution in the CCP. The through-plane conductivity test showed that CCP with 70 wt% carbon fiber, 10 wt% carbon powder, and 20 wt% polymer was the optimum sample, and it showed the highest electrical conductivity of 2.22 S cm-1. The physical properties of PTFE-treated CCP, such as porosity, density, and contact angle, were almost similar to that of commercial carbon paper used as a GDL. Therefore, the CCP prepared from coconut coir can be applied as a GDL in a PEMFC."

"The main problem with the slurry process is the difficulty in recovering the photocatalyst nanoparticle from water following purification. An alternative solution proposed the photocatalyst be immobilized on magnetic carriers, which would allow them to be recollected from the water suspension following treatment using an external magnetic field. Magnetically photocatalyst composites were prepared using simple heteroagglomeration by applying attractive electrostatic forces between the nanoparticles with an opposite surface charge. The Fe3O4/SiO2/TiO2 photocatalysts were synthesized in an aqueous slurry solution containing Fe3O4/SiO2 and TiO2 nanoparticles under pH 5 conditions. Meanwhile, Fe3O4/SiO2 was prepared by a simple procedure via a coprecipitation of iron(II) and iron(III) ion mixtures in ammonium hydroxide and was leached by sodium silicate. The synthesized samples were investigated to determine the phase structure, the magnetic properties, and the morphology of the composites by X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and transmission electron microscopy (TEM), respectively. The results indicated that the composites contained anatase and rutile phases and exhibited a superparamagnetic behavior. Fe3O4/SiO2 particles, which were of the aggregation spherical form at 20 nm in size, were successfully attached onto the TiO2 surface. The catalytic activity of Fe3O4/SiO2/TiO2 composites was evaluated for the degradation of methylene blue under ultraviolet (UV) irradiation. The presence of SiO2 as a barrier between Fe3O4 and TiO2 is not only improves the photocatalytic properties but also provides the ability to adsorb the properties on the composite. The Fe3O4/SiO2/TiO2 (50% containing TiO2 in composite) were able to eliminate 87.3% of methylene blue in water through the adsorption and photocatalytic processes. This result is slightly below pure TiO2, which is able to degrade 96% of methylene blue. The resulting Fe3O4/SiO2/TiO2 composite exhibited an excellent ability to remove dye from water and it is easily recollected using a magnetic bar from the water. Therefore, they have high potency as an efficient and simple implementation for the dye effluent decolorization of textile waste in slurry reactor processes."

"Agricultural waste hasincreased colossally with development in agricultural production causing environmentalnuisance and degradation. Utilization of coconut husks, one of such type of waste, as a biosorbent for polluted surface water treatment, wasconsidered in this study. Polluted surface water was gently passed through twosimilar columns loaded with 100 and 200 g of coconut husk char respectively.The treated water samples collected after 30, 60, 90, 120 and 150 mins wereexamined for SO42-, NO3- and PO43-ions concentration. Removal efficiency for SO42-, NO3-and PO43- ions on 100 g coconut husk char after 150mins detention time were 70, 78 and 91% respectively. Freundlich isotherm modelgave a better description of the data (R2 > 0.96). Sorption datawas well described by second order pseudo kinetics (R2 >0.85). An amount of 100 g of the biosorbenthas astrong affinity for these types of ion removal in contaminated water. Coconut huskchar as a biosorbentis a panacea to significant concentrations of polyatomic ions in polluted surface water."

"The antimicrobial properties of bagasse paper sheets coated withnatural polymers (chitosan, different ratios of (gelatin/glycerol) + chitosan,hemicellulose, hemicellulose + glycerol, hemicellulose+chitosan) orsynthetic organophosphorus dimer compounds were evaluated in this work.Hemicelluloses showed moderate activity against Bacillus subtilis and Candida albicans, while chitosan showed weakactivity against B. subtilis. The condition that offered the highest inhibitoryactivity of bagasse paper was the onecoated with 1,3-diaryl-2,2,2,4,4,4-hexachlorocyclodiphosph(V)azane(where aryl is p-chloroaniline or p-anisidine). The developed bagasse paperswere evaluated against Gram-positive bacteria, Gram-negative bacteria, yeasts, and fungi. The highest inhibitory activity was obtained at a concentration of 200mg/mL for p-chloroaniline with an inhibition zone that varied for differentmicrobes from 6.9 mm to 26 mm. The highest inhibitory activity was obtained at300?250 mg/mL for p-anisidine against most of the pathogenic microorganismswith an inhibition zone that varied for different microbes from 8 mm to 14.75mm. The observed antimicrobial and antifungal activity properties for bagasse paper coated with 1,3-diaryl2,2,2,4,4,4-hexachlorocyclodiphosph(V)azane could be attributed to the presence of Cl, P atoms, and the lone pair ofelectrons on N atoms in the structure of the dimers."

"Inhibition is one of themechanisms used for mitigating the metallic corrosion, particularly in an acid environment. The present work aims toinvestigate theinhibiting effect of N-benzyl-N/-phenyl thiourea (BPTU) on thecorrosion of low carbon steel in a 0.1 M hydrochloric acid (HCl) solution using a Tafelextrapolation and linear polarization techniques. The study reveals that BPTUacts as an excellent anodic inhibitor for low carbon steel in a HClsolution. The protective efficiency of the compound was found to be more than97% even at higher temperatures. The study demonstrated that BPTU gets adsorbedon the steel surface, following Temkin?s adsorption isotherm and the inhibitionis controlled by a chemisorptionmechanism. The investigation shows that the results obtained from the Tafelextrapolation and linear polarization techniques for the corrosion of mildsteel in HCl medium were in good agreement. The influence of temperatures andconcentrations of BPTU on the corrosion of low carbon steel are alsoexamined in the present work."

"Tesis ini membahas tentang faktor-faktor yang mempengaruhi kinerja Program Insentif Percepatan Difusi dan Pemanfaatan Iptek dari mulai faktor input sampai dengan outcome dengan menggunakan metode logic model. Penelitian ini menggunakan pendekatan kualitatif yang bersifat deskriptif analitik. Hasil analisis menunjukkan bahwa faktor input yang sangat berpengaruh dalam pelaksanaan Program Insentif Percepatan Difusi dan Pemanfaatan Iptek adalah sumber daya manusia, proposal, waktu serta mitra peneliti. Seleksi proposal yang dilakukan oleh tim penilai independen harus memenuhi syarat dan ketentuan yang sudah ditetapkan oleh Kemenristek. Outcome jangka panjang yang seharusnya bisa tercapai ternyata masih membutuhkan proses yang lama dan panjang serta memerlukan dukungan dari pihakpihak terkait. Hasil penelitian ini menyarankan agar proposal yang diterima diprioritaskan pada proposal yang mempunyai potensi tinggi untuk ketercapaian outcome jangka panjang. Disarankan pula agar Kemenristek berkoordinasi dan bersinergi dengan kementerian terkait lainnya untuk mendukung kebijakan mengenai tindak lanjut penerapan teknologi serta transfer teknologi yang dihasilkan dari pembiayaan Program Insentif Percepatan Difusi dan Pemanfaatan Iptek ini.

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This thesis studies the factors that affect the performance of Incentive Program Technology Diffusion and Utilization start from input factors to outcomes using logic models method. This study uses a descriptive analytic that is a qualitative approach.

The result of analysis showed that the most influential factor inputs in the implementation of Incentive Program Diffusion and Utilization of Science and Technology are human resources, proposal, timing and research counterpart. Selection of proposal that was conducted by an independent assessment team must conform to the terms and conditions set by Kemenristek. Long-term outcomes that should be achieved still require long process and need support from relevant stakeholders.

The results of this study suggest to received priority on proposals that have a high potential for the achievement of long-term outcome. And suggest Kemenristek to coordinate and synergize with other relevant ministries to support policy concerning implementation and transfer technology as a result from financing of Incentive Program Technology Diffusion and Utilization."

"Oil palm empty fruit bunch (OPEFB) is one of the waste products of oil palm plantations and has not been optimally used in Riau Province, Sumatera, Indonesia. OPEFB is reduced by incineration, which causes pollution problems. However, the combustion of OPEFB generates ash, which is rich in potassium. Moreover, OPEFB fiber has good strength, low cost, low density, and biodegradability, and it can be used as composite reinforcement. However, the natural fibers in composites have poor compatibility with the matrix and relatively high moisture absorption. Hydrolysis of OPEFB ash creates a base solution that can be utilized in an alkaline treatment process to increase the mechanical properties of natural composites.The aim of this study was to investigate the effect of various extracts of OPEFB ash on the tensile strength, flexural strength, and water absorption of an OPEFB fiber-polypropylene composite. The experimental design used was the Response Surface Method-Central Composite Design (RSM-CCD). The results showed that the tensile strength increased with an increase of fiber length and concentration of the OPEFB ash extract solution, but tensile strength decreased with a longer soaking time. Flexural strength increased with an increase in fiber length but decreased with an increase in the concentration of the OPEFB ash extract solution and longer soaking time. Water absorption increased with lower and higher concentrations of OPEFB ash extract solution and fiber length and with shorter and longer soaking times. The highest tensile strength (20.100 MPa) was achieved at 5%wt alkaline concentration, 36 h soaking time, and 3 cm fiber length. The highest flexural strength (30.216 MPa) was achieved at 5%wt alkaline concentration, 12 h soaking time, and 3 cm fiber length. The lowest water absorption (0.324%) was achieved at 10%wt alkaline concentration, 24 h soaking time, and 2 cm fiber length."

"In 2016, the mandatory use of biodiesel as a substitute fuel by up to 20%,as introduced by the Indonesian Ministry of Energy and Mineral Resources,forced vehicle manufacturers to invent suitable engines that would acceptbiodiesel. The use of biodiesel in such a large proportion is highly risky,particularly due to the formation of deposits in the combustion chamberengines. The previous method of fuel droplets are placed on a hot plateapproach produces deposits are slightly different from those generated by areal engine, therefore to obtain realistic deposits it is necessary to modifythis method so temperatures as hot as those in a real engine. In this study,the potential deposit formation of biodiesel fuel was examined by conductingthe deposition process and the evaporation of fuel on a stainless-steel plate(SS), which was placed in a closed space. Deposit characterization was carried outon a hot plate using Scanning Electron Microscopy (SEM). The test results showeddifferences in the structures of the deposits produced by biodiesel and dieselfuel; fine structures were seen in the former, while those of the latter wererougher and more porous. Deposit results that are similar to what is seen in areal engine will be very helpful for knowing the patterns, structures, and mechanismof the formation of deposits in such an environment."

"The performance of a 20 MW gas turbine power plant was described by using the exergy analysis and data from the plant?s record books. The first and second laws of thermodynamics, as well as the mass and energy conservation law, were applied in each of the components. The results show that more exergy destruction occured in the combustion chamber up to 71.03% or 21.98 MW. Meanwhile, the lowest exergy occured in the compressor at 12.33% or 3.15 MW. Thermal efficiency of the gas turbine power plant, according to the first law, was 33.77%, and exergy efficiency was 32.25%."