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Is Fatimah
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eksakta@uii.ac.id
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+6282326298724
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eksakta@uii.ac.id
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Faculty of Mathematics and Natural Sciences Universitas Islam Indonesia Jl. Kaliurang Km 14, Ngaglik, Sleman, Yogyakarta, 55584
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Daerah istimewa yogyakarta
INDONESIA
EKSAKTA: Journal of Sciences and Data Analysis
Published by Universitas Islam Indonesia
ISSN : 27160459     EISSN : 27209326     DOI : 10.20885
Core Subject : Science, Engineering,
Chemical Engineering, Chemistry & Bioengineering Chemistry Earth & Planetary Sciences Materials Science & Nanotechnology
Ekstakta is an interdisciplinary journal with the scope of mathematics and natural sciences that is published by Fakultas MIPA Universitas Islam Indonesia. All submitted papers should describe original, innovatory research, and modelling research indicating their basic idea for potential applications. The Journal particularly welcomes submissions that focus on the progress in the field of mathematics, statistics, chemistry, physics, biology and pharmaceutical sciences.
Arjuna Subject : Kimia(semua kategori) - Kimia (Lain-Lain)
Articles 6 Documents
 1 
Search results for , issue "VOLUME 14, ISSUE 1, February 2014" : 6 Documents clear
Adsorption Isotherm of Cr(VI) Using Mg/Al Hydrotalcite with Molar Ratio 2:1 Bayu Wiyantoko; Puji Kurniawati; Tri Esti Purbaningtias
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 14, ISSUE 1, February 2014
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

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Abstract

Hydrotalcite is a material which is used in various application and one of them as an adsorbent of Cr(VI). Hydrotalcite was synthesized using co-precipitation method with Al(NO­3)3.9H2O and Mg(NO3)2.6H2O as raw materials. This research aim to study the initial concentration and adsorption isotherm of Cr(VI) by using Mg/Al hydrotalcite in 180 minutes contact time. The Optimum initial concentration of Cr(VI) was 675 mg/L with 55,57 mg/g adsorption capacity. Isotherm adsorption was studied using Langmuir and Freundlich model. Based on the result, the adsorption of Cr(VI) fitted well with Langmuir isotherm model by 0,997 coefficient of determination
Decreasing in Acid Number of Patchouli Oil by Different Natural Adsorbent and Variation of Contact Time Tri Esti Purbaningtias; Bayu Wiyantoko; Puji Kurniawati; Mustika Kusuma Sari
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 14, ISSUE 1, February 2014
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

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Abstract

One way for improving (of improving atau to improve) the quality of patchouli oil was to reduce the acid number. Acid number could be reduced with the use of natural adsorbents. The decreasing percentage acid number of patchouli oils using adsorbents zeolites, bentonite, rub ash, and activated carbon, respectively 4.71 %; 1.45%; 7,84%; and 4.64%. The contact time could influence the decrease in acid number of patchouli oil. The longer the contact between adsorbent and oil could caused a decrease in acid number. Maximum contact time for rub ash was 15 hours with a maximum adsorption capacity of 14,34% for 0.1 gram adsorbent
Fuzzy T2 Hotelling (T_f^2 ) Control Chart Ayundyah Kesumawati; Mashuri Mashuri; Irhamah Irhamah
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 14, ISSUE 1, February 2014
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

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Abstract

Statistical Process Control (SPC) is a method used to monitor a process for identifying special causes of variation and necessary to improve the process. One technique commonly used in the SPC is to determine whether the process is stable or not, both the mean and variability. Multivariate control charts are used if necessary to control together two or more related quality characteristics. Sometimes in a process production there is a lack of precision in the calculation, especially if the data used in the form of either data or qualitative attributes. Fuzzy set theory, specifically discusses the development of concepts and techniques related to the sources of uncertainty or imprecision in nature. Control charts are constructed by transforming crisp numbers into fuzzy numbers can be an alternative to obtain representative results of several variables in which there are several quality characteristics. Transformation of some functions, which are used in this study is Fuzzy Median Transformation (FMT). The advantages of FMT is that it can be used for the data in the form of asymmetry. This paper will discuss about the algorithm for  Fuzzy T2  Hotelling control chart and its application to the production data of PT. IGLAS (Persero). From the results of the application of Fuzzy T2  Hotelling control chart got that out of the 5 variables that were analyzed, the dominant variables that lead to out of control is variable bottle molding process
Waste Cooking Oil Conversion To Biodeisel Catalized By Egg Shell Of Purebred Chiken With Ethanol As A Solvent Hellna Tehubijuluw; I Wayan Sutapa; Mealan Lethulur
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 14, ISSUE 1, February 2014
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

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Abstract

The synthesis of biodiesel from the waste cooking oil was carried out using the catalyst from egg shell of purebred chiken with ethanol as a solvent. Synthesis of biodiesel was prepared in two steps, esterification and transesterification. Esterification was conducted in mol ratio of ethanol and waste cooking oil of  9:1 with H2SO4 as a catalyst. Mol ratio of ethanol and used cooking oil in the transesterification of  12:1 with the CaO catalyst of shell eggs. CaO catalyst was yielded by calcinations egg shell of purebred chicken on 1000 for two hours. Calcination product was characterized with XRD to determine of CaO. Result of biodiesel was characterized based on FTIR, H-NMR, dan ASTM (American Standard Testing of Materials). Theoretically,yielded of biodiesel was 58% and experiment was 36.779%.
IMPROVEMENT OF THE PRODUCT AND QUALITY OF POGOSTEMON CABLIN BENTH Allwar Allwar; is fatimah; noor fitri; dwiarso rubiyanto
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 14, ISSUE 1, February 2014
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

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Abstract

Pogostemon cablin benth is an economic source of farmer communities which are presence in several provinces in Indonesia. In general, the production and quality of the Pogostemon cablin benth produced by the farmers are still low or under the standard ISO. The chelating method, the influence of pH and adsorption method with activated carbon and montmorilonite  were carried out to improve the production and quality of Pogostemon cablin benth. The results show that the production and the quality tends to be better proved by the color changes to yellow bright, reduced metal contents and an increase in Pogostemon cablin benth
Antibacterial Activities of Green Basil (Ocimum Violaceum) Essential Oil and Derivatives By MAOS (Microwave Assisted Organic Synthesis) Against Staphyllococus Aureus and Escherichia Coli Dwiarso Rubiyanto; Hady Anshory; Hardjono Sastrohamidjojo; Chairil Anwar
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 14, ISSUE 1, February 2014
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

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Abstract

Green basil (Ocimum violaceum , Linn.) plantis part of the varieties of basil (Ocimum basilicum, Linn.). Green basil essential oil (GBEO) contain chemical compounds that have an anti- bacterial activities . Methyl eugenol and methyl chavikol are in green basil oil has the potential to be used as a material which is biologically active. Conversion reaction of the compounds in GBEO with MAOS methods (microwave assisted organic synthesis) aims to obtain properties of the main chemical component in a wider sweet basil oil, and are also useful in an attempt to gain more valuable compounds for commercial and higher. The results showed that the optimum reaction conditions on the conversion reaction of compounds in GBEO with MAOS method with ethylene glycol as a solvent is 10 % KF/Al2O3as catalyst and reaction time 3 minutes , while the solvent is glycerol 10 % KF/Al2O3as catalyst and reaction time 2 minutes . Comparison of anti-bacterial activity resulting from this research are : the inhibitory activity to the growth of S. aureus bacteria have the following order : GBEO > green basilEG10-3 > green basil G10-2> amoxicillin with each inhibition zone diameter amounted to 30.7 mm, 21.1 mm, 18.2 mm and 13.4 mm. While the inhibitory activity to the growth of E.coli bacteria are : GBEO> green basil G10-2 >green basil EG10-3 > amoxicillin with each inhibition zone diameter of 21.1 mm, 15.6 mm , 15.2 mm and 7.9 mm . GBEO and its derivatives have minimal inhibitory concentrations below 1.25 %. From the results of the study found that the main derivates obtained are p-methoxy anisaldehyde , caryophyllene oxide , 3-methoxy cinnamaldehyde , humulena oxide and delta cadinol

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