The paper describes the effect of velocity ratio for mixing glycerol nitration in microchannel hydrodynamic that focused on the stream width. The method used are experimental and theory modeling of hydrodynamic fluid flow focused on predicting behavior stream width glycerol nitration.The research uses microchannel hydrodynamics focused on consisting of three channels inlet (one core and two sheaths). The core glycerol the beginning of the sheath distributed nitric acid with sulphuric acid as a catalyst. The length channel dimension of inlet and outlet of L 1 , L 2 , L 3 = 1000 μm, L 4 = 4000 μm with the width of D 1 , D 2 , D 3 , D 4 = 300 μm, and the depth of w =200 μm. using transparent material that is acrylic with thickness (T 1 and T 2 ) as 5 mm arranged accumulated. Fluid volume glycerol of the core of 2 ml, and volume nitric acid of 1.05 ml (+ aquades 0.75 ml) and sulphuric acid 0.1 ml (+ aquades 0.1 ml). The independent variable namely variation the velocity ratio (v 2 / v 1 ) 0.5, 1,2,3,4,5,6,7,8,9,10, and 11. It is Added a slight coloring yellow to fluid glycerol and red to a fluid mixture of nitric acid and sulphuric acid, to understand the mixing process of fluid at the reaction of glycerol nitration. The mixing of the measurement of stream width performed on the ratio of the length (α = L 4 / L 1 ) of 1 , 2 and 3.The result shows that diffusion of regional differences takes place in the velocity ratio shown by color changing of data on the picture. The width of focus stream is smaller as increasing the velocity ratio. This is caused by the pressure of a fluid channel sheath against core channel fluid is greater than diffusion reaction, as well as the energy required that is used to form a molecular bond.

Synthesis of iron oxide FeOOH from FeCl 3 , followed by thermal transformation to form red hematite was conducted. The effect of pH and temperature calcinations was studied. The observed parameters were include crystal structure, grain size, color, particle size distribution, and morphology. The result showed that α-Fe 2 O 3 structure with relatively pure and good crystallinity were found at all designated synthesis condition. The highest degrees of redness and chroma, uniformity of morphology and particle size distribution were achieved at pH 6, while the lowest degrees was formed at pH 8. The pigment at pH 6 has spherical-like shape with an average size of 0.16±0.057 μm. Instead, at pH 8 has spherical-like and cubic-like shape with an average grain size of 0.17±0.051 μm. The highest degrees of brightness, redness, yellowness and the highest chroma as well as smallest grain size of 0.15±0.052 μm were achieved at 800 o C but at this temperature the crystal orientation of 006 was not appear and the presence of 2θ angle (63.99 o) were supposed as crystal defects and impurity.

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Telah dilakukan penelitian tentang isolasi selulosa dari jerami padi menggunakan variasi konsentrasi basa. Pada penelitian ini dipelajari tentang pengaruh basa dan variasi konsentrasinya dalam isolasi selulosa dari jerami padi. Kajian pengaruh basa dan konsentrasi dilakukan dengan melarutkan ekstrak jerami padi pada NaOH dan KOH dengan variasi konsentrasi 1%, 3%, 5%, 7% dan 9% dan kemudian dilakukan analisis IR terhadap selulosa hasil isolasi serta dihitung rendemen selulosa dan lignin sisa. Hasil penelitian menunjukkan bahwa pada isolasi selulosa dari jerami padi digunakan NaOH 7% dengan rendemen selulosa yang diperoleh sebesar 33,63% dengan lignin sisa sebesar 2,42%.Kata kunci : isolasi, selulosa, lignin sisa