cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
Is Fatimah
Contact Email
eksakta@uii.ac.id
Phone
+6282326298724
Journal Mail Official
eksakta@uii.ac.id
Editorial Address
Faculty of Mathematics and Natural Sciences Universitas Islam Indonesia Jl. Kaliurang Km 14, Ngaglik, Sleman, Yogyakarta, 55584
Location
Kab. sleman,
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 8 Documents
 1 
Search results for , issue "VOLUME 16, ISSUE 2, August 2016" : 8 Documents clear
Synthesis and Characterization of 2,3,4-Trihydroxy-5-methyl Xanthone as Antimalarial Compound Dhina Fitriastuti; Jumina Jumina; Priatmoko Priatmoko
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art4

Abstract

Synthesis of xanthone derivatives had been conducted to obtain new antimalaria active compounds. The characterization of the synthesized xanthones was also conducted. Synthesis of xanthone was conducted from the raw material of hydroxybenzoic acid and phenol derivatives using Eaton's reagent via acylation-dehydration reaction by modified Grover, Shah and Shah (GSS) method. The synthesis of 2,3,4-trihydroxy-5-methyl xanthone was carried out using gallic acid, o-cresol and Eaton's reagent.The mixture was heated for 3 h at 80 °C to yield 2,3,4-trihydroxy-5-methyl xanthone in 43% yield as dark red viscous liquid. The results of IR, 1H-NMR and 13C-NMR analysis of sampleshowed that the compound2,3,4-trihydroxy-5-methyl xanthonehas successfully synthesized.
Synthesis of Chalcones Substituted with Nitro and Hydroxyl Group in Alkaline Medium Lina Fauzi'ah; Tutik Dwi Wahyuningsih
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art5

Abstract

Telah dilakukan sintesis turunan senyawa kalkon tersubstitusi gugus nitro dan hidroksi melalui reaksi kondensasi Claisen Schmidt. Tujuan penelitian ini adalah untuk mensintesis senyawa kalkon yang tersubstitusi gugus hirdoksi dan nitro dalam medium basa, dan mempelajari pengaruh gugus tersebut dalam reaksi kondendasi. Kalkon 1 disintesis dari 4-nitroasetofenon dan vanilin menggunakan katalis NaOH 60% (b/v dalam akuades) melalui pengadukan selama 24 jam. Kalkon 2 didapatkan dari reaksi antara 4-nitroasetofenon dan veratraldehida dengan katalis NaOH 15% selama 4 jam, sedangkan kalkon 3 disintesis dari 4-nitroasetofenon dan 6-nitroveratraldehida dalam 5% NaOH 10 tetes. Produk hasil sintesis dikarakterisasi dengan FTIR, GC-MS dan 1H-NMR.Hasil penelitian menunjukkan bahwa senyawa kalkon telah berhasil disintesis dengan rendemen berturut-turut sebesar 16,80; 75,83; dan 44,11 % dalam medium basa. Dari penelitian ini, dapat disimpulkan bahwa adanya gugus hidroksi dari sumber aldehida aromatik pada kalkon 1 menghambat terjadinya reaksi, sedangkan gugus nitro yang terikat pada aldehida aromatik menjadi kendala pada reaksi kalkon 3 karena sifatnya yang sensitif terhadap cahaya.
Bootstrapping Residuals to Estimate the Standard Error of Simple Linear Regression Coefficients Muhammad Hasan Sidiq Kurniawan
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art1

Abstract

Regression models are the statistical methods that widely used in many fields. The models allow relatively simple analysis of complicated situations. The aim of the regression models is to analyze the relationship between the predictor and response. In order to do that, we have to estimate the regression coefficient. In case of simple linear regression, the method to estimate the regression coefficient is either least square method or maximum likelihood estimation. Also, the standard error of the regression coefficient is being estimated. In this paper, we apply the bootstrap method to estimate the standard error of the regression coefficient. We compare the result of the bootstrapping method with the least square method. From this study, we know that the standard error estimation value of regression model using the bootstrap method is close to the value if we use the least square method. So we can say that the bootstrap method can be used to estimate the standard error of another regression models coefficient which does not have the closed-form formula
Effect of Adding 1,4-Butanediol and Polyethylene Glycol (PEG) 1000 to the Ease of Bioplastic Biodegradation from Jackfruit Beans (Artocarpus heterophyllus) Argo Khoirul Anas; Nanang Rudianto Ariefta; Yuni Nurfiana; Eli Rohaeti
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art6

Abstract

The influences of plasticizer on the biodegradability of bioplastic film synthesized from starch obtained from jackfruit seeds with a help of Acetobacter xylinum were investigated. In this study, 1,4-butanediol and polyethylene glycol (PEG) 1000 were used as plasticizer. The biodegradation behavior of the resulted bioplastic films was characterized by calculating changes in their mass loss and rate of mass loss. The Fourier Transform Infrared (FTIR) spectroscopy was also conducted to analyze theirfunctional group. The results shows that all the bioplastic films were well biodegradated, where PEG 1000 with concentration of 0,5% and 1,0% can successfully improve the biodegradability of bioplastic film. Meanwhile, the used of 1,4-butanediol with concentration of 0,5% and 1,0% can increase and decrease the biodegradability of sample, respectively.
Utilization of Waste Extracts Residual Tobacco Cigarette Manufacturing and Leaves of Mahkota Dewa as a Natural Pesticide for Pest Control Armyworms in Chili Plant Cahyati Cahyati; Marlina Marlina Marlina; Rizqy Nurlestari Nurlestari; Indrasti Dwi Puji lestari; Tatang Shabur Julianto
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art2

Abstract

The use of pesticides is still considered behind a great benefit for increasing agricultural production. Quite high negative impact of the use of synthetic pesticides to encourage efforts to pursue the empowerment of natural pesticide as alternative to synthetic pesticides. On tobacco and leaves of mahkota dewa found a substance alkaloid that can help ward off attacks, especially armyworm. Has conducted research utilization of waste residual tobacco cigarette manufacturing at a company and leaves of mahkota dewa as a natural pesticide to eradicate the armyworm. The residual tobacco cigarette manufacturing and leaves of mahkota dewa isolated manner extracted with an organic solvent so that the resulting crude extract alkaloids. The resulting crude alkaloid used as a pesticide solution sprayed on the leaves of chili to eradicate the pest armyworms. Test result showed that the insecticidal activity of alkaloid extract concentration of 1,6 ppm has the highest insecticidal activity. However, engaging both the alkaloid extract provides insecticidal activity is lower than the alkaloid extract of leaves of mahkota dewa so that the most effective in the use of alkaloid extract of leaves of mahkota dewa. Identification of the alkaloid compounds have been analyzed by TLC. This analysis showed that compound in waste of tobacco cigarette manufacture is nicotine and triterpenoids whereas the alkaloid extract of the leaves of mahkota dewa form of narcotic
The Study of In-Migration between Provinces in Indonesia by Panel Data Regression Asmadhini Handayani Rahmah
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art7

Abstract

Indonesia has 34 provinces. There are many peoples spread out across Indonesia and the vast area owned makes Indonesia become one of the biggest 4 (four) most population country in the world. However, the population density is not spread evenly in Indonesia. This has become interesting to be observed how the distribution of population in Indonesia by using variable in-migration as a dependent variable that is assumed to be influenced by four (4) independent variables. Thoseindependent variables are the Gross Domestic Product (GDP), the Regional Minimum Wage, Unemployment Rate (TPT) and Labor Force Participation Rate (LFPR). Data is collected fromwww.BPS.go.id . The analysistool used panel data regression, denote a data type is a combination of time series data (time series) and cross section data. The best selected model used in this research is Fixed Effect model to obtain 33 models for 33 provinces. The variables that influence the inmigration is the Open unemployment rate (TPT), which has a negative correlation to in-migration, while the Labor Force Participation Rate (LFPR) has a positive correlation.
Green Chemistry: Effect of Microwave Irradiationon Synthesis of Chitosan for Biomedical Grade Applications of Biodegradable Materials Amri Setyawati; Deni Pranowo; Indriana Kartini
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art8

Abstract

Microwave assisted chitosan synthesis as biodegradable material for biomedical application has been done. The purpose of this research is to synthesis of chitosan with high DD and low molecular weight using microwave energy, the study of reaction conditions include parameters of power and reaction time. Chitosan was prepared by deacetylation of chitin with 60% NaOH solution. Conventional method has been done by reflux for 90minutes, resulting chitosan with DD of 79.5%, 72.6% yields and molecular weight 6051 g/mol. Green chemistry method using microwave radiation at 800 Watts for 5 minutes has produced chitosan with highest DD, yield and molecular weight of 86%, 75% and 3797 g/mole respectively. Synthesis of Chitosan by microwave radiation method can save 10x electrical energy for the reaction, also rapidly and effectively to produce chitosan with low molecular weight compared to conventional methods
Characterization And Study Of Iron(III)-Released From Alginate/Zeolite/Fe Composite Nia Silvia Sukma; Yateman Arryanto; Sutarno Sutarno
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 2, August 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss2.art3

Abstract

Alginate is an organic polymer that is isolated from brown algae and bacteria, while the zeolite is an aluminosilicate mineral sample. The purpose of this study was to synthesize composite alginate / zeolite / Fe, characterize composite alginate / zeolite / Fe, and assessing the release properties of Fe (III) of the composite alginate / zeolite / Fe. Characterization of the composite is done by observing the color composite macroscopically, and observing the pattern of distribution of zeolite particles in composites using SEM (Scanning Electron Microscope). As for assessing the release of Fe (III) of the composite system made by soaking the composite in a solution of citric acid 0,33M for nine hours. Components of Fe (III) were dissolved in acid systems were analyzed using UV-Vis spectrophotometer.The results showed that the composite alginate / zeolite / Fe have colors that are significantly dependent on the component ratio of alginate and zeolitnya. SEM analysis provides information that the zeolites distributed evenly on alginate-Fe phase. The release profile of Fe (III) of the composite alginate / zeolite / Fe weight variation component alginate produced three mechanisms to increase and decrease the rate of release of Fe (III). While the release profile of Fe (III) of the composite alginate / zeolite / Fe by weight of the zeolite component generates two mechanisms that increase and decrease the rate of release of Fe (III).

Page 1 of 1 | Total Record : 8

 1 

Filter by Year

2016 2016


Reset
Filter By Issues
All Issue VOLUME 6, ISSUE 2, October 2025 VOLUME 6, ISSUE 1, April 2025 VOLUME 5, ISSUE 2, October 2024 VOLUME 5, ISSUE 1, April 2024 VOLUME 4, ISSUE 2, August 2023 VOLUME 4, ISSUE 1, February 2023 VOLUME 3, ISSUE 2, August 2022 VOLUME 3, ISSUE 1, February 2022 VOLUME 2, ISSUE 2, August 2021 VOLUME 2, ISSUE 1, February 2021 VOLUME 1, ISSUE 2, August 2020 VOLUME 1, ISSUE 1, February 2020 VOLUME 19, ISSUE 2, August 2019 VOLUME 19, ISSUE 1, February 2019 VOLUME 18, ISSUE 2, August 2018 VOLUME 18, ISSUE 1, February 2018 VOLUME 17, ISSUE 2, August 2017 VOLUME 17, ISSUE 1, February 2017 VOLUME 16, ISSUE 2, August 2016 VOLUME 16, ISSUE 1, February 2016 VOLUME 15, ISSUE 1-2, 2015 VOLUME 14, ISSUE 2, August 2014 VOLUME 14, ISSUE 1, February 2014 VOLUME 13, ISSUE 1-2, August 2013 VOLUME 13, ISSUE 1, February 2012 VOLUME 12, ISSUE 2, August 2011 VOLUME 12, ISSUE 1, February 2011 VOLUME 11, ISSUE 2, August 2010 VOLUME 11, ISSUE 1, February 2010 More Issue