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"The purpose of this paper was to investigate the performance of ceramic filters made from a mixture of natural clay, rice bran, and iron powder in removing cadmium from pulp industry effluent. Some parameters were examined such as acidity, total dissolved solid (TDS), total suspended solid (TSS), electrical conductivity (EC), and cadmium concentration. Results showed that the composition percentage of the ceramic filter, which in this case amounted to 87.5% natural clay, 10% rice bran, and 2.5% iron powder, may decrease cadmium concentration in pulp industry effluent by up to 99.0%. Furthermore, the permeate flux decreased after 30 minutes of filtration time, and subsequently became constant at one hour of contact time. In addition, Scanning Electron Microscope (SEM) micrographs of the ceramic filter surfaces indicate that ceramic filters have a random pore structure and can be categorized as microfiltration filters."

"e purpose of this paper was to investigate the performance of ceramic filters made from a mixture of natural clay, rice bran, and iron powder in removing cadmium from pulp industry effluent. Some parameters were examined such as acidity, total dissolved solid (TDS), total suspended solid (TSS), electrical conductivity (EC), and cadmium concentration. Results showed that the composition percentage of the ceramic filter, which in this case amounted to 87.5% natural clay, 10% rice bran, and 2.5% iron powder, may decrease cadmium concentration in pulp industry effluent by up to 99.0%. Furthermore, the permeate flux decreased after 30 minutes of filtration time, and subsequently became constant at one hour of contact time. In addition, Scanning Electron Microscope (SEM) micrographs of the ceramic filter surfaces indicate that ceramic filters have a random pore structure and can be categorized as microfiltration filters."

"The combination ofbaffled air flotation and a membrane system for the treatment of palm oil milleffluent (POME) was studied. The POME was obtained from a palm oil factory inPTPN I Tanjong Seumantoh, Aceh, Indonesia. Operation variables and conditions,such as the hydraulic retention time and air flow rates, were varied to findthe optimum process. The air flotation process is able to reduce theconcentration of suspended solids and fats/ oils contained in the wastewater,which increases the performance of the membrane by reducing clogging. Theresults showed that this method was promising for POME treatment. The optimumorganic removal efficiency of the air flotation pretreatment was obtained atHRT = 5 days and at an air flow rate of 11 L/min. The effluent was subsequentlypassed through an anaerobic membrane system to achieve the highest removalefficiency treatment. The removal efficiency of chemical oxygen demand (COD),total suspended solids (TSS), turbidity, mixed liquor suspended solids (MLSS),mixed liquor volatile suspended solids (MLVSS), and fats/oils after passingthrough the membrane system were 97%, 93.9%, 99.8%, 94.5%, 96.2%, and 99.9%,respectively. The results also showed that the pH could be neutralized to 6.18,while a dissolved oxygen (DO) level of 1.60 mg/L could be achieved. A highquality of effluent was obtained, which met the standards for POME effluent."

"Recently, there was anincrease in demand of biomass pellets as an alternative energy source. However,it is necessary to reduce the size of granular materials during the pelleting process.The size reductionof eucalyptus bark occurs in the industrialprocessing of biomass pellets production, using a hammer milltogether with three sieve sizes of 3, 4, and 5 mm and the sieve speeds of 900, 1000, 1100, and 1200 rpm, respectively, which have beenexamined at a feed rate of 80 kg/h. The aims of this study were to determine theimportant parameters, namely rotational speed, to determine suitable sieve sizefor reducing the size of eucalyptus bark, and to analyze energy usage in thesize reduction process by using a hammer mill. The results have shown that using a 5 mm sieve size at 900 rpm sievespeed resulted in the best operating conditions in order to offer the highestcapacity and lowest specific energy consumption. Moreover, the average particle size of 0.15mm was an acceptable value. This study could be very beneficial in thedevelopment process to produce biomass pellets."

"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."

"This study aimed to determine the effect of using acrylonitrile butadiene styrene in place of conventional wax material on treatment pattern removal in the investment casting process. There are three controllable process variables that can affect treatment pattern removal, which include temperature increase, holding time and the number of layers of ceramic shell that have been considered for comparison. Comparison among the effects of temperature increase, holding time and numbers of ceramic shell layers on the ceramic shell was analyzed using ANOVA. It was found that temperature increase (Tx), holding time (t) and number of layers of ceramic shell (N) contribute significantly to the length of the crack (l) on the ceramic shell. The crack in the ceramic shell?s surface was analyzed using scanning electron microscope photos. Less layers number cause the increase of crack length. The combination between temperature upraise and longer holding time cause cracking delay. The experimental is conducted by using 3 (three) variants for each of layers number, temperature and holding time. The layers number is ranging between 7-9 layers. Temperature increase from room temperature until 1300oC. The layers number variant is ranging between 180-300 seconds. It was concluded that a longer holding time will result in a more intact ceramic shell, as longer holding times yield short crack lengths."

"in this paper, a 4.2GHz collinear antena is designed to be used for computer management of vehicles/communication utility that can be integrated into combat systems, that is air defense systems (ADS) and combat field management systems (CMS)."

"East Java Province inIndonesia is the centre of the eastern Indonesia region and it has a fairlyhigh economic significance, which has contributed 14.85% to the national GrossDomestic Product (GDP). The role of Large and Medium Scale ManufacturingIndustry (LMSMI) clusters in this province is very important and strategic asone of the main drivers for economic progress and it becomes a part of theefforts to improve the society's life. Therefore, it is necessary to evaluatethe performance of LMSMI clusters continuously. The purpose of this study is toinvestigate the productivity changes of LMSMI clusters in East Java Province,Indonesia, so that they will be able to survive, grow and compete in facingglobal competition. The method used in this study is the method of DEA-basedMalmquist Productivity Index. The result of this study indicates that 50% ofthe LMSMI clusters in East Java Province are in the category of improvedproductivity, while the remaining clusters are in the category of decliningproductivity."

"The choice among modes of intercity transport depends on conditions of not only intercity transport modes but also intracity transport in both the departure city and the arrival city. Intracity transport conditions might be advantageous for one intercity mode and disadvantageous for others. Intercity and intracity transport conditions are complex and need to be approached systemically. This study proposes an approach based on the passengers? preferences. The logit model was adapted to evaluate the transport modes? choices in competition. This model is called the ?Adapted Mixed Multinomial Logit Model? (AMML). It was applied on the Jakarta-Bandung corridor in both directions. It contributes to a complete approach for intercity transport mode choice by considering the influence of the intracity transport conditions in both the departure and arrival cities. The results proved that the choice of intercity transport mode depends not only on its own quality of service but also, importantly, on that of the intracity transport systems."