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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 231 Documents
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Physical-Mechanical Properties And Microstructure Of Breadfruit Starch Edible Films With Various Plasticizer Cut Fatimah Zuhra Marpongahtun
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 13, ISSUE 1-2, August 2013
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol13.iss1-2.art7

Abstract

Breadfruit contains starch can be used as raw material of edible film. Research on preparation of edible films using various types of plasticizer (xylitol, sorbitol and PEG 400) has been done. The edible films were evaluated of physical-mechanical properties and microstructure. The results of this study indicate that the addition of plasticizer effect on the physical and mechanical characteristics, the edible film thickness, tensile strength and water vapor transmission rate greater using PEG 400 but percent elongation smaller than xylitol and sorbitol. Surface analysis of film was performed using Scanning Electron Microscopy (SEM) method.Keyword : Edible Film; Pati Sukun; Plasticizer; Silitol; Sorbitol ; PEG 400
Monitoring Penggunaan Formalin Pada Daging Ayam (Observation The Use Of Formalin In Chicken) Roza Azizah Primatika; Heru Susetya; Arselia Kartika Sari
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 15, ISSUE 1-2, 2015
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol15.iss1-2.art6

Abstract

Chicken is one of source of animal protein which consumed by many people. Although the animal protein is needed as a source of nutrition, the product becomes a danger when contain of formalin. This study aims to determine the level of use of formaldehyde in chicken meat in Yogyakarta traditional markets and the factors associated with the incident. The samples used were 56 chickens, obtained from 11 traditional markets in Yogyakarta were chosen randomly. Each sample was tested using two reagent is phenylhydrazine and Quantofiq. Interpretation of test phenylhydrazine that is colored bluegreen solution and eventually turned into a red-orange color if the sample is positive, and yellow if it is negative. At Quantofiq test the color will be formed at the end of the detection paper, then color matched to the color table to determine levels of formaldehyde in the samples tested. The results showed that 6 (10,7%) positive samples contain of formaldehyde and analysis of Chi-Square showed that p_value = 0.045. So sales location were association with used of formaldehyde in chicken meat.
Film Of Chitosan-Carboxymethyl Cellulose Polyelectrolyte Complex as Methylene Blue Adsorbent Febi Indah Fajarwati; Eko Sugiharto; Dwi Siswanta
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 1, February 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss1.art5

Abstract

Telah dilakukan pembuatan film kompleks polielektrolit kitosan-karboksimetil selulosa (CMC) untuk pengujian pengaruh rasio volume CMC:kitosan (1:1; 3:2; 7:3). Karakterisasi film dilakukan dengan uji kuat tarik, medium asam basa, dan penyerapan air serta dilakukan uji adsorpsi terhadap biru metilen. Hasil Karakterisasi menunjukkan sifat mekanik film menurun dengan bertambahnya jumlah karboksimetil selulosa dan film stabil pada pH >4. Kondisi optimum adsorpsi diperoleh pada film F3 (ratio volume CMC:kitosan 7:3) dengan kapasitas adsorpsi sebesar 8,38×10-5 mol/g selama 30 menit.
An Alternative Forecasting Using Holt-Winter Damped Trend for Soekarno-Hatta Airport Passenger Volume Arum Handini Primandari
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 17, ISSUE 1, February 2017
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol17.iss1.art1

Abstract

Located in the capital city of Indonesia, Soekarno-Hatta Airport is considered as the main airport. Since there are some aviation companies providing low cost flight, the number people coming and leaving trough this airport has increased. The passenger volume can be considered as seasonal data since it shows increment in particular months, such as long holiday. Knowing in advance the volume of passenger will help the government to improve its service effectively. There is a simple and accurate method for forecasting seasonal data that is called Holt-Winter Exponential Smoothing (HWE). However, HWE always encounters over forecasting problem when it is employed to forecast in some future periods (m>1). In order to solve this problem, we add the damped parameter that will be damping the exponentially growth on HWE. This method called HWE damped trend. We employed the domestic passenger volume data of Soekarno-Hatta Airport from January 2008 till December 2015. This data collected from prior research. As the result, HWE damped trend outperforms traditional HWE on either training data set or testing data.
Synthesis of 4 Phenyl 3,4 Dihydr Indeno[2′,1′]Pyrimidine 2 One on Different Amount of Catalysts Ritmaleni Ritmaleni; Megawati Parmasari
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 12, ISSUE 1, February 2011
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Dihydropirimidine  is  a  heterocyclic  compound  which  has  important  pharmacologic  and  therapeutic  activities.  This  compound  can  be  synthesised  by  using Biginelli  reaction  which  involve  three  type  of  starting  materials  and  also  have  been developed  into  different method    of  reaction  condition  and  starting material.  LR1  (4phenyl3,4dihydroindeno[2′,1′]pyrimidine2one)  is  a  derivative  of  dihydropirimidine. This research was aimed to study the effect of catalyst amount in the synthesis of LR1 in order to reach the optimal yield.  LR1 can be synthesised form benzaldehyde, urea adn 2indanone in ethanol and concentrated chloric acid as catalyst for five hours under reflux. The product mixture was then  extracted  and  isolated  by  column  chromatography  preparative.  The melting  point was checked to determine the purity of the product. The structure elucidation was carried out by using spectroscopic method (uvvis, IR, 1HNMR and MS) The result showed that the highest yield of LR1 was obtained around 15 % when 0.25 %  of chloric acid used as catalyst. The higher the condition of acid in the reaction, the lower the tield of LR1 obtained.
Standardization of Specific and Non-Specific Parameters of Propolis Extract as Raw Material for Herbal Product Yandi Syukri; Ririk Purwati; Nadia Hazami; Hady Anshory Tahmid; Annisa Fitria
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 1, ISSUE 1, February 2020
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/EKSAKTA.vol1.iss1.art6

Abstract

This study aims to standardize the specific and non-specific parameters of propolis extract originating from East Java, Indonesia, to fulfil the requirements as a herbal raw material. Standardization was carried out on propolis ethanol extract taken at three different harvesting times. Standardization was carried out on specific parameters including the content of dissolved compounds, chemical content of extracts and chromatogram patterns, while the non-specific parameters of the extract included water content, ash content residue, density, microbial contamination, and heavy metal contamination. Specific extract parameters showed that the water-soluble extract content was 2.1-3.5%; levels of ethanol-soluble extract 62.00-84.00%; total flavonoid levels of 0.015-0.072 mg ER / g; and total phenol content of 0.0039-0.0053 mg ER / g. Non-specific parameters indicate that the water content is 10.72-10.90%; drying losses 10.05-10.63%; total ash content of 0.08-0.65%, density of 0.88-0.89 g / mL; Pb levels from 6.55-9.01 mg / kg; Cd content of 0.50-1.22 mg / kg, Cu content of 0.82-1.13 mg / kg; the total plate number is 10 colonies / g and the yeast fungus number is 10 colonies / g. It can be concluded that propolis extract from the East Java region of Indonesia fulfills the requirements as a raw material for herbal products in Indonesia.
Preparation And Characterization Of Microporous Activated Carbon From Oil Palm Shell By Physical Activation Using Purified Nitrogen Allwar Allwar; Ahmad Md Noor; Moh Asri Moh Nawi
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 12, ISSUE 2, August 2011
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Oil palm shell, a byproduct of palm oil industry was successfully used as a raw material for the production of highly porous activated carbons. Preparation of activated carbon was carried out by physical activation under nitrogen at various activation temperatures. The nitrogen isotherms show Type I characteristics of microporous activated carbon. The maximum surface areas obtained at 900oC was 936 m2g-1. The morphology structure of the activated carbon indicated the existence of the porosities with different size pores. Keywords: Oil palm shell; Micropores; Physical activation; Nitrogen adsorption-desorption isotherm
Nori Nutrient Analysis from Seawed of Porphyra marcossi in Maluku Ocean Voulda D Loupatty
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 14, ISSUE 2, August 2014
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol14.iss2.art4

Abstract

Penelitian “Analisis Gizi Nori Dari Rumput Laut Jenis Porphyra marcossi Yang Terdapat Di Perairan Maluku” dilakukan dengan tujuan menganalisis kualitas gizi nori yang dihasilkan dari rumput laut Porphyra marcossi, yang nantinya mampu menggantikan penggunaan nori impor untuk memenuhi kebutuhan dalam negeri. Adapun prosedur kerja proses pembuatan nori adalah rumput laut kering dicuci bersih, setelah bersih dilakukan pemotongan kecil-kecil / diblender. Selanjutnya direbus dengan perbandingan rumput laut:air=1:10 dengan penambahan sedikit cuka. Perebusan dilakukan selama ± 1 jam. Setelah itu dicetak berbentuk lembaran tipis, dikeringkan dan dikemas. Dalam penelitian ini dilakukan pengujian terhadap produk yang dihasilkan meliputi kadar protein, lemak, abu dan air, yang mengacu pada SNI 01-2891-1992, serta identifikasi asam amino dengan menggunakan metode hidrolisis asam basa. Hasil penelitian menunjukan bahwa rumput laut Porphyra marcossi mempunyai nilai gizi yang cukup tinggi yaitu : protein 28,60% ; lemak 0,83% ; abu 17,80% dan air 28,09%. Produk Nori mempunyai nilai gizi : protein 41,49% ; lemak 0,44% ;abu 4,99%;air 13,14%. Terdapat 10 jenis asam amino yaitu treonin, arginin, tirosin, meteonin, lisin, valin, asam glutamate, glisin, fenilalanin dan alanin. Teknologi pengolahan Nori cukup sederhana dan mudah dikembangkan dalam industry rumah tangga untuk meningkatkan pendapatan keluarga. Kebutuhan Nori dalam negeri dapat dipenuhi dengan adanya indutri pengolahan nori berbasis sumber daya alam lokal.
Study on Lignin Isolation from Oil Palm Empty Fruit Bunches Nurcahyo Iman Prakoso; Suryo Purwono; Rochmadi Rochmadi
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 16, ISSUE 1, February 2016
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol16.iss1.art6

Abstract

Telah dilakukan studi tentang isolasi lignin dari tandan kosong kelapa sawit dengan metode batch. Diharapkan melalui studi ini dapat memperoleh metode isolasi lignin yang optimal. Studi yang dilakukan meliputi optimasi suhu reaksi, rasio massa NaOH terhadap pelarut, rasio serabut terhadap pelarut, dan waktu reaksi. Dari semua perlakuan, didapatkan bahwa suhu reaksi, tekanan, konsentrasi NaOH, rasio serabut terhadap pelarut dan waktu reaksi optimum berturut-turut yaitu, 170 °C, 15 atm, 1% (b/v), 9% (b/v), dan reaksi dilakukan selama 5 jam
Comparison the Error Rate of Autoregressive Distributed Lag (ARDL) and Vector Autoregressive (VAR) (Case study: Forecast of Export Quantities in DIY) Dewi Kusuma Ningrum; Sugiyarto Surono
EKSAKTA: Journal of Sciences and Data Analysis VOLUME 18, ISSUE 2, August 2018
Publisher : Fakultas Matematika dan Ilmu Pengetahuan Alam

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20885/eksakta.vol18.iss2.art8

Abstract

Forecasting is estimating the size or number of something in the future. Regression model that enters current independent variable value, and lagged value is called distributed-lag model, if it enters one or more lagged value, it is called autoregressive. Koyck method is used for dynamic model which the lagged length is unknown, for the known lagged length it is used the Almon method. Vector Autoregressive (VAR) is a method that explains every variable in the model depend on the lag movement from the variable itself and all the others variable. This research aimed to explain the application of Autoregressive distributed-lag model and Vector Autoregressive (VAR) method for the forecasting for export amount in DIY. It takes export amount in DIY and inflation data, kurs, and Indonesias foreign exchange reserve. Forecasting formation: defining Koyck and Almon distributed-lag dynamic model, then the best model is chosen and distribution-lag dynamic forecasting is performed. After that it is performed stationary test, co-integration test, optimal lag examination, granger causality test, parameter estimation, VAR model stability, and performs forecasting with VAR method. The forecasting result shows MAPE value from ARDL method obtained is 0.475812%, while MAPE value from VAR method is 0.464473%. Thus it can be concluded that Vector Autoregressive (VAR) method is more effective to be used in case study of export amount in DIY forecasting. Keywords: Koyck; Almon; Lag; Autoregressive Distributed-Lag; Vector Autoregressive;

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