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Indonesian Journal of Chemistry

ijc
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Published by Universitas Gadjah Mada

ISSN : 14119420 EISSN : 24601578 DOI : -

Core Subject : Science, Engineering,

Chemical Engineering, Chemistry & Bioengineering Chemistry

Indonesian Journal of Chemistry is an International, peer-reviewed, open access journal that publishes original research articles, review articles, as well as short communication in all areas of chemistry including applied chemistry. The journal is accredited by The Ministry of Research, Technology and Higher Education (RISTEKDIKTI) No : 21/E/KPT/2018 (in First Rank) and indexed in Scopus since 2012. Since 2018 (Volume 18), Indonesian Journal of Chemistry publish four issues (numbers) annually (February, May, August and November).

Arjuna Subject : -

Articles 1,981 Documents

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RESVERATROL DIMERS FROM STEM BARK OF Hopea gregaria AND THEIR CYTOTOXIC PROPERTIES Sahidin Sahidin; Euis Holisotan Hakim; Yana Maolana Syah; Lia Dewi Juliawaty; Sjamsul Arifin Achmad; Laily Bin Din; Jalifah Latip
Indonesian Journal of Chemistry Vol 8, No 2 (2008)
Publisher : Universitas Gadjah Mada

Six resveratrol dimers have been isolated from the stem bark of H. gregaria, ampelopsin A (1), balanocarpol (2), ε-viniferin (3), hopeafuran (4), heimiol A (5), and parviflorol (6). The structures of these compounds were determined based on spectroscopic evidence such as UV, IR, 1-D, 2-D NMR and comparison with the reported data. These compound inventions are strengthen conclusion that Hopea tends to produce resveratrol dimers. Biological activity of those compounds against murine leukemia P-388 cells showed that ε-viniferin (3) is the most active compound with IC50 value 5.1 ± 0.3 μg/mL.

SEDIMENTS AND NUTRIENT DYNAMICS IN THE LAKE MARKERMEER, THE NETHERLANDS Philiphi de Rozari
Indonesian Journal of Chemistry Vol 9, No 1 (2009)
Publisher : Universitas Gadjah Mada

Lake Markermeer is a large fresh water lake in the centre of the Netherlands. Since Lake Markermeer is categorised as a shallow lake, it is very susceptible for sediment resuspension. The general objective of this study is to investigate sediment and nutrient dynamics in Lake Markermeer sediments. This research was carried out in a 5 months period from November 2007 until March 2008 using sediment trap methods. Sampling sites for sediment traps are located at the two fixed sites in which each sampling site had duplicates bottom and half-depth traps. The collection of the sediment traps samples was conducted every two weeks. The parameter measured in sediment traps were: sediment trap yields, Loss on ignition (LOI), total N and total P. Statistical t test analysis was utilised to compare the value of each parameter between two sampling stations as well as between bottom and half depth at the same stations.The results for the sediment trap activities showed that at the two fixed sampling stations, the sediment trap yields in the bottom part tend to be higher than half depth. This difference between bottom and half-way traps is statistically significant. Also, a significant difference was found between STA and STB, both for bottom and half-depth traps. A similar result was found for LOI. For total N and P the results showed that there were no significant differences between bottom and half-depth at the two fixed sampling stations.

SYNTHESIS OF FAUJASITE WITH HIGH THERMAL STABILITY FROM FLY ASH Sutarno Sutarno; Yateman Arryanto
Indonesian Journal of Chemistry Vol 4, No 1 (2004)
Publisher : Universitas Gadjah Mada

Faujasite was hydrothermally synthesized from fly ash at 100oC in alkaline solution by reflux with various concentration of HCl and fusion with NaOH (weight ratio of NaOH/fly ash = 1.2) pretreatments. Thermal stability of faujasite from fly ash was tested at 400-900oC and was compared with commercial zeolite Y. The solid products were characterized by X-ray diffraction method, chemical analysis and nitrogen adsorption (BET). Results showed that synthesis of faujasite from fly ash via fusion pretreatment with NaOH has resulted faujasite selectively, however, the faujasite obtained still showed relatively low thermal stability due to its relatively low of Si/Al mol ratio. Reflux pretreatment with HCl was an effective method not only to increase the Si/Al mol ratio but also to decrease the metal impurities in the fly ash sample. Synthesis of faujasite from fly ash via combination of reflux with HCl and fusion with NaOH pretreatment has resulted faujasite selectively with higher Si/Al mol ratio. Faujasite obtained from fly ash via combination of reflux with HCl and fusion with NaOH pretreatment showed thermal stability as high as commercial zeolite NaY.

(-)-AMPELOPSIN A : A DIMER RESVERATROL FROM Dryobalanops oblongifolia (dipterocarpaceae) Nanik Siti Aminah; Sjamsul Arifin Achmad; Masatake Niwa; Yana Maolana Syah; Euis Holisotan Hakim
Indonesian Journal of Chemistry Vol 6, No 1 (2006)
Publisher : Universitas Gadjah Mada

A dimer resveratrol compound named (-)-ampelopsin A was isolated from acetone extract of the stem bark of Dryobalanops oblongifolia (Dipterocarpaceae). The structure of this compound was determined on the basis of NMR spectroscopic data.

BENZYLISOQUINOLINE ALKALOIDS FROM BARK OF Cryptocarya rugulosa Nurdin Saidi; Hiroshi Morita; Marc Litaudon; Mat Ropi Mukhtar; Khalijah Awang; A. Hamid A. Hadi
Indonesian Journal of Chemistry Vol 11, No 1 (2011)
Publisher : Universitas Gadjah Mada

Seven known Benzylisoquinoline alkaloids, Papraline 1, (+)-norcinnamolaurine 2, (+)-codamine 3, (+)-6-methoxy-1-(3'-methoxybenzyl)-N-methyl-7-isoquinolinol 4, (+)-reticuline N-oxide 5, (+)-reticuline 6 and (-)-N-methylisococlaurine 7 were isolated from bark of Cryptocarya rugulosa. A combination of 1D-NMR (1H, 13C, DEPT, NOE), 2D-NMR (COSY, NOESY, HMQC, HMBC), MS (HRESI+, FAB+ and EI) spectroscopy used to elucidate the structure.

PREPARATION, CHARACTERIZATION AND CATALYTIC ACTIVITY TEST OF CoMo/ZnO CATALYST ON ETHANOL CONVERSION USING STEAM REFORMING METHOD Wega Trisunaryanti; Handirofa Handirofa; Triyono Triyono; Suryo Purwono
Indonesian Journal of Chemistry Vol 9, No 2 (2009)
Publisher : Universitas Gadjah Mada

Preparation, characterization and catalytic activity test of CoMo/ZnO catalyst for steam reforming of ethanol have been investigated. The catalysts preparation was carried out by impregnation of Co and/or Mo onto ZnO sample. Water excess was used in ethanol feed for steam reforming process under mol ratio of ethanol:water (1:10). Characterizations of catalysts were conducted by analysis of metal content using Atomic Absorption Spectroscopy (AAS). Determination of catalysts acidity was conducted by gravimetric method of adsorption of pyridine base. Catalytic activity test on ethanol conversion using steam reforming method was conducted in a semi-flow reactor system, at a temperature of 400 oC, for 1.5 h under N2 flow rate of 10 mL/min. Gas product was analyzed by gas chromatograph with TCD system. The results of catalysts characterizations showed that the impregnation of Co and/or Mo metals on ZnO sample increased its acidity and specific surface area. The content of Co in Co/ZnO and CoMo/ZnO catalysts was 1.14 and 0.49 wt%. The Mo content in CoMo/ZnO catalyst was 0.36 wt%. The catalytic activity test result on ethanol conversion showed that the ZnO, Co/ZnO, and CoMo/ZnO catalysts produced gas fraction of 16.73, 28.53, and 35.53 wt%, respectively. The coke production of ZnO, Co/ZnO, and CoMo/ZnO catalysts was 0.86, 0.24, and 0.08 wt%, respectively. The gas products consisted mainly of hydrogen.

Ion Ni2+ di Dalam Air; Pembentukan Fungsi Potensial Intermolekul Bambang Setiaji; Tutik Arindah
Indonesian Journal of Chemistry Vol 2, No 2 (2002)
Publisher : Universitas Gadjah Mada

Pair potential function of Ni2+-H2O system has been constructed by ab initio method at UHF (Unrestricted Hartre-Fock) level. The basis sets used for energy interaction calculation were LANL2 Double-z ECP of Hay and Wadt for Ni2+ and Double-z Polarization of Dunning for H2O. Construction of pair potential function was done by collecting more than 3000 energy points that represent all interactions of Ni2+ ion and water. The pair potential function of Ni2+-H2O resulted of fitting proses by standard deviation of 3,25 kcal/mol is where AiM, BiM, CiM and DiM are fitting parameter of Ni2+-O or Ni2+-H, riM is distance of i atoms between H2O and Ni2+, q is charge of i atoms of H2O resulted by Mulliken population analysis, and qM is net charge of Ni2+ ion.

EFFECT OF CERIUM ON HYDRODESULFURIZATION CATALYST PERFORMANCE Triyono Triyono; Wega Trisunaryanti
Indonesian Journal of Chemistry Vol 8, No 1 (2008)
Publisher : Universitas Gadjah Mada

Effect of cerium on hydrodesulfurization catalysts performance have been investigated. The catalysts were Pt or Pt-Ce supported on zeolite. The Pt/Zeolite catalyst was prepared by wet impregnation method, while that of Pt-Ce/Zeolite catalyst was prepared using coimpregnation method both were followed by drying, calcination, oxidation and reduction. The catalysts activity test was performed in a micro reactor and products composition was determined using gas chromatography. The results showed that cerium enhanced catalyst performance especially catalyst lifetime. Therefore, the catalysts have higher tendency to remain active for longer period. Due to its function, cerium might be used as a promoter of hydrodesulfurization catalysts.

THE USE OF FLY ASH AND ZEOLITE MIXTURE AS BACKFILL MATERIAL IN THE RADIOACTIVE WASTE REPOSITORY Herry Poernomo; Noor Anis Kundari; Burhani J W
Indonesian Journal of Chemistry Vol 5, No 3 (2005)
Publisher : Universitas Gadjah Mada

An investigation of the contribution of fly ash in the fly ash-zeolite mixture as the backfill material on the shallow land burial of radioactive waste has been done. The experiment objective is to know the effect of zeolite particle size and fly ash-zeolite weight ratio on physical properties such as permeability (K) and dispersion characteristic such as effective dispersion coefficient (De) in the fly ash-zeolite form as backfill material. The experiment was carried out by the fixed bed method in the column filled by the fly ash-zeolite mixture with a fly ash-to-zeolite weight percent ratio of 100/0, 80/20, 60/40, 40/60, 20/80, 0/100 in the water saturated condition flown by uranyl nitrate solution at concentration (Co) of 500 ppm. The concentration of uranium in the effluents in interval 15 minutes represented as Ct was analyzed by spectrophotometer, then using Co and Ct, data effective dispersion coefficient (De) in the backfill material were determined. The experiment data showed that -400 mesh fly ash and -70+80 mesh zeolite on fly ash-to-zeolite with weight percent ratio of 40/60 with K = 5.00x10-5cm/second and De = 1.11.10-5 cm2/second can be used as backfill material.

THE USE OF CHLOROSULFONIC ACID ON SULFONATION OF cPTFE FILM GRAFTED STYRENE FOR PROTON EXCHANGE MEMBRANE Yohan Yohan
Indonesian Journal of Chemistry Vol 7, No 3 (2007)
Publisher : Universitas Gadjah Mada

Sulfonation of g-ray iradiated and styrene-grafted crosslinked polytetrafluoro ethylene film (cPTFE-g-S film) have been done. The aim of the research was to make hydrophyl membrane as proton exchange membrane fuel cell. Sulfonation was prepared by using chlorosulfonic acid in chloroethane under various conditions. The impact of the percentage of grafting, the concentration of chlorosulfonic acid, the reaction time,and the reaction temperature on the properties of sulfonated film were examined. The results show that sulfonation of surface-grafted films was incomplete at room temperature. Increasing concentration of chlorosulfonic acid and reaction temperature accelerate the reaction but they also favor side reactions. These lead to the decrease of the ion-exchange capacity, water uptake, and proton conductivity but the increase of the resistance to oxidation in a perhydrol solution. The resulted cPTFE-g-SS membraneis stabile in a H2O2 30% solution for 20 h.

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