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"The effect of precipitant and ultrasonic over Ni7CeO,-MgO-La,0/A503 catalyst was studied in an atmospheric fixed-bed reactor for partial oxidation of methane. Two types of precipitant used in this work were Na2C)3 and NH4OH2 and the length of ultrasonic iradiation was 60 minutes (1 hour). The bulk surface area, nickel particle diameter, nickel dispersion and morphology of the catalysts were investigated by various characterization techniques, including BET] XRD, H; chemisorption and SEM The partial oxidation of methane to syngas was done at 800 ?C atmospheric pressure and the feed ratio (CH/01) was 2 : 1.2. It was found that catalysts prepared by using NH4OH2 precipitant have pore size that larger than those of catalysts prepared using Na,CO, precipitant. The effect of ultrasonic on the catalysts showed that ultrasonic irradiation enhanced the surface area of the catalyst and the nickel dispersion. SEM analyses shown changes of the catalyst morphology, i.e. the particle of the catalyst became smaller and more uniform because of the ultrasonic irradiation. Catalyst prepared using NH,0H precipitant and irradiated shown the best performance with 96% methane conversion."

"The combination between frames and walls is frequently used in the earthquake resistant design of multistorey reinforced concrete buildings Frames are relatively flexible , it will deform according to the shear mode. Meanwhile walls are usually very stift and it will deform with the flexural one. Accordingly between frames and walls will have a conflict of deformation modes. There is no clear guidance regarding the appropriate ratio between the number of walls and frames. In addition, effects of the rocking foundation to the structural response need to be investigated The seismic behavior of the multistorey reinforced concrete building has been investigated Three types of structure i.e 2 Walls +5 Frames or 2W+5F, 2W+7F and 2W+9F have been used for the structural models. The corresponding structural models are 12- storey buildings with 2 symmetrical beams span and _symmetrical buildings plan. The North-South Component of the 1940 El Centro earthquake record has been used for the input motion. The stifness and damping interaction between the soil and the foundation according to the Lumped ParameterMethod are also used The results of investigation show that the smaller the wall-frame ratio , the bigger the base shear coefficient resisted by walls, the smaller the plastic hinge rotation of the column 's bases, the smaller the total plastic hinge rotation and the hysteretic energy dissipation of every frame. In general, the structural response of the rocking structures are smaller than those the _fixed base structures. The appropriate wall frame-ratio can not be defined definitely without any clear requirement of the design criteria."

"y-alumina (AL2O3) is one of catalyst support widely used in cotalytic process. From technological aspect, producing y-alumina bauxite is not a new technology, moreover, Indonesian bauxite reserves as its raw material is huge. This research consists of bauxite digestion using Bayer method gibbsite precipitation using neutralization of sodium aluminate by C01 method hydrothermal process for transforming gibbsite to boehmite, and boehmite calcination to produce y-alumina. The result shows the total extraction percentage of 7'-alumina is 51.52 %. The XRD characterization which is also supported by FTIR characterization shows that precipitation product is bayerite, hydrothermal process has transformed bayerite to boehmite, and calcination product is y-alumina. The surface area of y-alumina produced at calcination temperature 550, 675, and 800 are 52, 43, and 43 m2/g, respectively. SEM characterieation indicates fibrous shape of boehmite morphology. The XRF characterization shows impurities found in bayerite and boehmite are Fe, Si, Ti, and S."

"The application of bio-oil for biofuel has been limited due to its low heating value, high acidity and high oxygenate content. pursuant to the urgency of obtaining access to sustainable energy from renewable resources, the studies for bio-oil upgrading have been recently placed in high priority. this study is aimed at identifying the effect of biomass types on bio-oil product characteristics. the conversion of several types of biomass, i.e. rice straw, rubberwood (hevea brasiliensis), and palm empty fruit bunches (efb) to bio-oil by-products was investigated in a catalytic fast pyrolysis (cfp) reactor using a ni/zsm-5 nickel nitrate and zeolite catalyst at 550oc and at atmospheric pressure. the results show that ni/zsm-5 catalyst has actively enhanced the de-oxygenation reaction process and aromatic production. the composition of aromatic compounds in bio-oil from rubberwood, rice straw, and efb are 10.25 wt%, 7.8 wt%, and 5.98 wt%, respectively. in the absence of a catalyst, bio-oil from rice straw contains no aromatics."