Papers by seri bima sembiring
Indian Journal of Science and Technology, Dec 16, 2014
Adsorption and desorption of carotenoids from crude palm oil (CPO) has been performed in ethanol,... more Adsorption and desorption of carotenoids from crude palm oil (CPO) has been performed in ethanol, using five types of adsorbents M-Polystyrene Sulfonate or M-PSS ( M = Na, Mg, Ca, Sr, and Ba ) which is Sulfonate salts. NaPSS first adsorbents is made by neutralizing a solution of polystyrene sulfonic acid with acetyl sulfate. Four other M-PSS adsorbents are made from a reaction between Na-PSS with each salt MgCl 2 , CaCl 2 , SrCl 2 and BaCl 2 . The five adsorbents are characterized by Melting Point Apparatus (MPA), Spectrophotometry Atomic Absorption (SAA), Transform Infra Red Spectrometer (TIRS), Scanning Electron Microscope (SEM), Surface Area Analyzer with Brunauer Emmet Teller (BET) and Transmission Electron Microscope (TEM). The treatment resulted in the adsorption 100%, desorption 78.75% and the carotenoids recovered 78.75%.
Journal of the Chemical Society, Dalton Transactions, 1999
... 5, J. Deisenhofer, O. Epp, K. Micki, R. Huber and H. Michel, Nature (London), 1985, 318, 618 ... more ... 5, J. Deisenhofer, O. Epp, K. Micki, R. Huber and H. Michel, Nature (London), 1985, 318, 618 Article ; H. Kurreck and M. Huber, Angew. Chem., Int. Ed. Engl., 1995, 34, 849 Article ChemPort . ... 34, (a) B. Yang, L. Liu, TJ Katz, CA Liberko and LR Miller, J. Am. Chem. ...
Advanced Materials Research, 2013
![Research paper thumbnail of Palladium(II) 2-diphenylphosphinohydroquinone (H2pphq) complexes: preparation and structures of a novel cluster, [{PdBr(Hpphq)}4]�2H2O, and a phosphine?phosphinite complex, cis-[PdBr2{C6H3(OH)-1,PPh2-3,PPh2O-4}]�2H2O](https://a.academia-assets.com/images/blank-paper.jpg)
Journal of the Chemical Society, Dalton Transactions, 1995
ABSTRACT The complexes [PdCl2(PPh3)L2](L2= 1,4-dimethoxy-2-diphenylphosphinobenzene), [PdCl(bipy)... more ABSTRACT The complexes [PdCl2(PPh3)L2](L2= 1,4-dimethoxy-2-diphenylphosphinobenzene), [PdCl(bipy)L2]+(bipy = 2,2′-bipyridine) and [PdCl2(mpy)L2](mpy = 4-methylpyridine) have been prepared and their reactions with BBr3 studied. The first two complexes afforded products resulting from protolytic cleavage of the phosphinohydroquinone ligand whereas reactions of the last with BBr3 produced [PdBr(mpy)(Hpphq-O,P)](H2pphq = H2L1= 2-diphenylphosphinohydroquinone) when quenched with methanolic sodium carbonate or, when quenched with methanol alone, a mixture which contains the novel tetrameric cluster [{PdBr(HL1)}4] and slowly deposits an unexpected phosphine–phosphinite complex, cis-[PdBr2{C6H3(OH)-1,PPh2-3,PPh2O-4}]·H2O, on standing. The crystal structures of the last two complexes have been determined. The palladium tetramer was also formed when [PdBr(mpy)(HL1-O,P)] was treated with hydrobromic acid. The NMR spectra suggest that in solution the tetramer is in equilibrium with monomeric solvato complexes, [PdBr(solv)(HL1-O,P)](solv = solvent).
Indonesian Journal of …, 2011
The optimization of enzymatic synthesis for lauroyl-N-methyl glucamide surfactants is studied. Th... more The optimization of enzymatic synthesis for lauroyl-N-methyl glucamide surfactants is studied. The fraction of palm kernel oil namely lauric acid (AL) was amidificationed with N-methyl glucamine (MGL) to produce lauroyl-Nmethyl glucamide. Study was carried out by using immobilized lipase from Candida antarctica (Novozyme 435 ® ), and tert-amylalcohol as a solvent. Response Surface Methodology (RSM) based on a five level, three variable design was employed, firstly, for studying the interactive effect of various parameters on the reaction, and secondly, for the optimization. The reaction parameters observed were Novozyme concentration, substrate molar ratio, and temperature. Simultaneously increasing Novozyme concentration, substrate molar ratio, and temperature improves the reaction yield and the effect of temperature is noted more significant. The expected optimum condition was at molar ratio MGL:AL 1:1, the Novozyme concentration of 8% and the reaction temperature of 50-55°C. The reactions at the optimum condition produce the convertion of lauric acid of 64.5% and yield of 96.5%. With the optimization procedure the higher alkyl glucamide yield was achieved.
Inorganica Chimica Acta, 1995
ABSTRACT The X-ray single crystal structures of two p-hydroquinonylphosphine complexes, trans-[Pd... more ABSTRACT The X-ray single crystal structures of two p-hydroquinonylphosphine complexes, trans-[PdCl2(pphgH2)2] (1) and trans-[PtCl2(pphgH2)2] (2)A and one p-hydroquinonyldimethyletherphosphine complex, trans-[PdCl2(pphqMe2)2] (3), are described. 1 co-crystallizes with two molecules of lattice-included acetone ((1)·(acetone)2) in the monoclinic space group C2/m with Z = 2 and cell constants a = 13.857(6) b = 13.589(3) c = 11.863(5)Å β = 104.68(2)°. Intermolecular hydrogen bonding between molecules of 1 leads to channels that run parallel to the c axis and which include the acetone guest molecules. Complex 2 co-crystallizes with four molecules of dimethylformamide solvent ((2)· (DMF)4) in the triclinic space group P1 with Z = 1 and cell constants a = 10.500(6), b = 11.927(8), c = 12.225(6) Å α = 64.65(5), β = 66.74(5) γ = 78.84(5)°. Each dimethylformamide molecule in (2)·(DMF)4 is hydrogen bonded to one of the four OH groups of 2. Complex 3 crystallizes in the triclinic space group P1 with Z = 1 and cell constants a = 9.063(5), b = 10.548(7), c = 11.596(8)Å α = 111.57(3), β = 111.26(3)A γ = 90.09( 4)°. It is shown that there is a close relationship between the molecular structures and the co-crystalline behavior of 1 and 2 and the molecular structures and inclusion properties of organic ‘wheel-and-axle’ host molecules. The analogy is extended to provide some guidelines for the design of new inorganic host molecules.
Inorganica Chimica Acta, 1990
... and X-ray crystal structure of the palladium phosphidoxo complex [Pd2(y/-I)2{(PPh20)2H}2]Step... more ... and X-ray crystal structure of the palladium phosphidoxo complex [Pd2(y/-I)2{(PPh20)2H}2]Stephen B. Colbran*, Don C. Craig and Seri Bima Sembiring Department of Inorganic and Nuclear Chemistry, University of New South Wales, PO Box 1, Kensington, NSW 2033 ...
Inorganica Chimica Acta, 1992
ABSTRACT The preparation and redox chemistry of the O,P-chelated, hydroquinonylphosphine complex ... more ABSTRACT The preparation and redox chemistry of the O,P-chelated, hydroquinonylphosphine complex cis-[Ni(pphqH)2] is reported, along with the crystal structure of cis-[Ni(pphqH)2]·H2O·2(CH3)2NCHO. The complex is isostructural with cis-[Pd(pphqH)2]. Differences in the reactivity, physical properties and redox chemistry of cis-[Ni(pphqH)2] and its palladium and platinum congeners are discussed.
Inorganic Chemistry, 1995
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Papers by seri bima sembiring