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INDONESIA
Science and Technology Indonesia
Published by Universitas Sriwijaya
ISSN : 25804405     EISSN : 25804391     DOI : -
Core Subject : Science, Social, Engineering,
Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Environmental Science Materials Science & Nanotechnology Physics
An international Peer-review journal in the field of science and technology published by The Indonesian Science and Technology Society. Science and Technology Indonesia is a member of Crossref with DOI prefix number: 10.26554/sti. Science and Technology Indonesia publishes quarterly (January, April, July, October). Science and Technology Indonesia is an international scholarly journal on the field of science and technology aimed to publish a high-quality scientific paper including original research papers, reviews, short communication, and technical notes. This journal welcomes the submission of articles that covers a typical subject of natural science and technology such as: > Chemistry > Biology > Physics > Marine Science > Pharmacy > Chemical Engineering > Environmental Science and Engineering > Computational Engineering > Biotechnology Journal Commencement: October 2016
Arjuna Subject : -
Articles 551 Documents
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Pre-Formulation Study on The Preparation of Skin Cosmetics Ahmad Ainurofiq; Anita Maharani; Fitri Fatonah; Hainun Nisa Halida; Tejayani Nurrodlotiningtyas
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.273-284

Abstract

Cosmetics have been a trend necessary for all people. The increasing need of the community in the use of cosmetics becomes the basis of the formulation of this article. Pre-formulation study for cosmetics is important to ensure that the final preparation of the cosmetics is safe to use and has maintained quality. A pre-formulation study for cosmetics is a study of physicochemical characteristics associated with the substances used in the formulation of cosmetics preparation to produce a quality cosmetic product. The pre-formulation study described here includes evaluation of sensitivity and irritability, organoleptic, formulation compatibility, thermal effect, partition coefficient, stability, particle size, wettability, hygroscopicity, type of preparation, and pH. This review article is compiled by searching for literature associated with the topic studied. Taken together, this review suggests that the pre-formulation study described recommended to be performed during the information searching step related to the physicochemical properties of ingredients used for cosmetic preparations. All of the topic studied is beneficial to determine the quality of the ingredients within the preparation before formulation, therefore, the production of cosmetic preparation can be more effective because it directs the choice of ingredients and optimum ingredient composition.
Numerical Simulation of Flood Routing through Channels with Area Variation using Staggered Grid Method Bambang Agus Sulistyono; Samijo; Aan Nurfahrudianto; Dian Devita Yohanie; Aprilia Dwi Handayani
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.261-266

Abstract

In the event that the discharge goes to enter the channel surpasses the channel ability, than would happen floods of genuine harm to the environment around the channel. Applying the dynamic wave model, the discharge amount could be predicted in the frequent flood region if the information of discharge upstream is found out. Many numerical schemes could be utilized to discover answers to the system of differential partial equations. We proposed the usage of the staggered method to find out the solution of the system. The numerical scheme shall be used to predict the top discharge in a frequent flood region and create a flooded pocket to diminish the top discharge in the region. Based on the outcome of the numerical simulation, we may claim that a stable scheme has been created to acquire the approach resolve of the equation partial system. The staggered scheme is capable of investigating the impact of the presence of the flood pocket especially lessening the top discharge.
Application of Non-Linear Kinetic and Isotherm Model for Investigation of Cod Removal from Tapioca Liquid Waste Onto Modified Lampung Natural Zeolite Didik Supriyadi; Darmansyah; Ratna Puspita Sari; Amna Citra Farhan
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.218-227

Abstract

The experimental data analysis of tapioca liquid waste onto modified Lampung natural zeolite using non-linear regression models is limited. The adsorption data were analyzed with nine kinetic models (the pseudo-first-order, the pseudo-second-order, the intraparticle diusion, fractional power, Bangham, Elovich, mixed-1.2-order, modification of pseudo-second-order, and Avrami) and eight isotherm models (Langmuir, Freundlich, Dubinin-Radushkevich, Sips, Redlich-Peterson, Toth, Liu, and Khan). The percentage of adsorption was decreased from 61.29% to 13.66% with increasing Chemical Oxygen Demand (COD) concentration 310 mg/L to 9450 mg/L. The result showed that the power model (R2 : 0.98, X2 : 0.137), Avrami (R2 : 0.98, X2 : 0.141), Bangham (R2 : 0.98, X2 : 0.145) and modified pseudo-second-order (R2 : 0.98, X2 : 0.147) can be recommended as the best fied to experimental kinetic data. The Khan model (R2 : 0.99961, X2 : 0.03729) and Langmuir (R2 : 0.99478, X2 : 0.24902) was the most reliable for describing the isotherm model. Thus, the analysis of experimental adsorption data using a non-linear regression model is highly recommended.
Formulation, Evaluation of Physical Properties, Anti-Cholesterol Activity from Ficus carica L. Leaves Extract Tablet Muhammad Fariez Kurniawan; Mia Audita
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.285-295

Abstract

Figs knew playing vital roles in reducing cholesterol, strengthening the heart, and controlling respiration. Figs leaves extract with a dose of 50 mg/kg and 100 mg/kg can reduce triglyceride levels and can increase HDL cholesterol levels. This study aims to determine the effect of Ficus carica L. (fig) leaves extract on tablet dosage forms to reducing total cholesterol in rats induced with pork fat feed. Tablets were made by the wet granulation method in three formulas, there are F1 (extract dose 50 mg), F2 (extract dose 100 mg), and F3 (extract dose 150 mg), and compared with simvastatin tablets. The rats used in this study were 40 animals which were divided into 8 groups. Negative control group (induced of pork oil), F1 group, F2 group, F3 group, F4 group (placebo), positive control group (simvastatin 10 mg), base suspending agent group, and normal group.The average weight (mg) of F1 tablets (605.96 ± 9.94%), F2 (611.81 ± 12.33%), and F3 (639.09 ± 4.65%). As for the uniformity of size, all formulas have a diameter of 0.9 ± 0.0 (cm). for the hardness values of F1 (6.54 kg), F2 (5.31 kg), and F3 (5.43 kg). The value of friability F1 (0.8%), F2 (1.38%), and F3 (0.77%). While the disintegration time of F1 (13.31 minutes), F2 (19.48 minutes), and F3 (21.11 minutes). Whereas the dissolution rate (DE45) of each formulation decreased with increasing dose of extract, F1 (69.43%), F2 (64.95%), and F3 (60.04%). Extract contain quercetin as flavonoid, saponin, polyphenol, alkaloid, and tannin. Based on the results of statistical analysis, extract tablets did not differ significantly from simvastatin tablets in reducing total cholesterol levels. Tablet formulation of fig leaves extract with a dose variant has been shown to reduce total cholesterol in the blood between 18.3% until 37.98%.
Handling Missing Data Using Combination of Deletion Technique, Mean, Mode and Artificial Neural Network Imputation for Heart Disease Dataset Anita Desiani; Novi Rustiana Dewi; Annisa Nur Fauza; Naufal Rachmatullah; Muhammad Arhami; Muhammad Nawawi
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.303-312

Abstract

The University of California Irvine Heart disease dataset had missing data on several attributes. The missing data can loss the important information of the attributes, but it cannot be deleted immediately on dataset. To handle missing data, there are several ways including deletion, imputation by mean, mode, or with prediction methods. In this study, the missing data were handled by deletion technique if the attribute had more than 70% missing data. Otherwise, it were handled by mean and mode method to impute missing data that had missing data less or equal 1%. The artificial neural network was used to handle the attribute that had missing data more than 1%. The results of the techniques and methods used to handle missing data were measured based on the performance results of the classification method on data that has been handled the problem of missing data. In this study the classification method used is Artificial Neural Network, Naïve Bayes, Support Vector Machine, and K-Nearest Neighbor. The performance results of classification methods without handling missing data were compared with the performance results of classification methods after imputation missing data on dataset for accuracy, sensitivity, specificity and ROC. In addition, the comparison of the Mean Squared Error results was also used to see how close the predicted label in the classification was to the original label. The lowest Mean Squared Error wasobtained by Artificial Neural Network, which means that the Artificial Neural Network worked very well on dataset that has been handled missing data compared to other methods. The result of accuracy, specificity, sensitivity in each classification method showed that imputation missing data could increase the performance of classification, especially for the Artificial Neural Network method.
The Characteristic Analysis of Caffeine Molecularly Imprinted Polymers Synthesized Using The Cooling-Heating Method, for Application as a Sensor Material Idha Royani; Amalia Amalia; Jorena Jorena; Fitri Suryani Arsyad; Erry Koriyanti; Fiber Monado
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.256-260

Abstract

The cooling-heating method was used to successfully synthesize molecularly imprinted polymers on caffeine. Caffeine was used as a template and mixed with chloroform solvent, methacrylic acid as a monomer, ethylene glycol dimethacrylate as a cross-linker, and benzoyl peroxide as an initiator. The solution was stirred for 15 minutes and placed in a vial. Then it was placed in a cooler with a temperature of -5○C for 60 minutes and then inserted into an oven with an increasing temperature at 75○C, 80○C, and 85○C for 3, 2 and 1 hour, respectively. Furthermore, the repeated washing process resulted in solid polymer, which was subjected to template leaching to produce polymers with specific cavities called molecularly imprinted polymers (MIP). The resulting caffeine polymer and MIP were tested using SEM, FTIR, and XRD methods. In addition, the SEM image analysis data showed 388 cavities in the polymer after template leaching, compared to the 121 cavities in the unwashed polymer. This result was supported by the FTIR spectrum analysis which showed that caffeine MIP has a higher transmittance value than the polymer. Therefore, the caffeine concentration was significantly reduced after the leaching process. The XRD spectra showed that caffeine MIP had a smaller halfmaximum diffraction peak width (FWHM) compared to the polymer. Also, the low FWHM value depicted a larger crystalline size in the caffeine MIP compared to the polymer.
ZnAl-Humic Acid Composite as Adsorbent of Cadmium(II) From Aqueous Solution Jeri Rahmadan; Veronika Parhusip; Neza Rahayu Palapa; Tarmizi Taher; Risfidian Mohadi; Aldes Lesbani
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.247-255

Abstract

The modified ZnAl composites with humic acid (HA/ZnAl composite) were a coprecipitation method used as an adsorbent to remove cadmium(II) in an aqueous solution. The synthesized material was characterized using SEM-EDX, FTIR, and XRD. From the analysis using XRD, there is a widening peak at an angle of 2???? (24°), FTIR analysis there is a new peak at 1000 cm−1 and 1220 cm−1 and SEM analysis show that there is a change in surface morphology due to more aggregated particles. The experimental results on HA/ZnAl composite followed the PSO model, where the cadmium(II) removal process was chemical adsorption. The adsorption isotherm follows the Langmuir model where adsorption occurs in a monolayer and maximum adsorption capacity was obtained 38.76 mg/g higher than pristine. Thermodynamics of the adsorption process of cadmium(II) in an aqueous solution occurred spontaneously where G < 0 at all temperatures and endothermic properties were tested. The performance of the HA/ZnAl composite showed that strong potential as an adsorbent of low cost, high efficiency, easy operation, and good reusability. The cadmium(II) was absorbed on the surface of HA/ZnAl composite by surface complexation and chelating interactions, and surface complexation was the main route of cadmium(II) removal. In addition, HA/ZnAl composite has excellent treatment efficiency in actual aqueous solution.
Time-Domain Optical Coherence Tomography System for Determining The Extinction Coefficient and Group Refractive Index of Gelatin-based Skin Phantoms Maria Cecilia Galvez; Edgar Vallar; Tatsuo Shiina; Ernest Macalalad; Paulito Mandia
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.319-327

Abstract

Optical Coherence Tomography (OCT) is a non-invasive, non-destructive optical imaging technique that uses a low coherence interferometer to obtain real-time cross-sectional images of samples. OCT is notably used in biomedical applications including ophthalmology and dermatology. Aside from generating cross-sectional images, axial scans can also provide additional information about its optical properties such as extinction coefficient and refractive index. This study determines the extinction coefficients and group refractive indices of gelatin-based skin phantoms using a portable time-domain (TD) – OCT system. The gelatin-based skin phantoms were fabricated with varying concentrations of titanium dioxide (TiO2), while keeping the amount of both gelatin and water constant. By changing the proportion of the gelatin powder and TiO2, skin phantoms can then be fabricated to mimic various skin conditions, both pathologic and non-pathologic. Results of the study found a positive correlation of extinction coefficient and refractive index with TiO2 concentration. Thus, increasing TiO2 concentration also increases both extinction coefficient and group refractive index. The median extinction coefficient values of the phantoms ranged from 4.29 mm−1 to 8.48 mm−1. Literature showed that the epidermis can have extinction coefficients of 1.64-7.3 mm−1. For refractive indices of the fabricated phantoms, values ranged from 1.32 to 1.48, while studies on human participants showed that human skin has refractive index values of 1.34-1.56. Based on these properties, it is feasible to fabricate phantoms simulating the optical properties of human skin.
Prediction of Plastic-Type for Sorting System using Fisher Discriminant Analysis Irsyadi Yani; Yulia Resti; Firmansyah Burlian; Ansyori Yani
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.313-318

Abstract

Recycling is a more environmentally friendly method of managing and reducing plastic waste that can significantly reduce land degradation, pollution, and greenhouse gas emissions. According to its composition, an essential first step in the recycling process is sorting out plastic waste. However, inadequate sorting of plastic types can result in cross-contamination and increasing industrial operating costs. A low-cost automated plastic sorting system can be developed by using digital image data in the red, green, and blue (RGB) color space as the dataset and predicting the type using learning datasets. The purpose of this paper is to demonstrate how to use Fisher Discriminant Analysis (FDA) to predict the plastic type from a digital image of the RGB model and then evaluate the performance using cross-validation. This work has four main steps: collecting plastic digital image data, forming statistical tests, predicting plastic types, and evaluating prediction performance. FDA is quite effective for predicting the type of plastic. Performance measures the accuracy of 87.11 %, the recall-micro of 91.67 %, the recall-micro of 80.97 %, the specificity-micro of 90.33 %, and the specificity-macro of 90.38 %, respectively. The micro is determined by the number of decisions made for each object. In comparison, the macro is calculated based on the average decision made by each class.
Polyisoprenoid Compounds from Tropical Fruit Trees in Universitas Sumatera Utara Campus Muttia Chandraputri Rizkiany; Rizka Amelia; Yuntha Bimantara; Hiroshi Sagami; Mohammad Basyuni
Science and Technology Indonesia Vol. 6 No. 4 (2021): October
Publisher : Research Center of Inorganic Materials and Coordination Complexes, FMIPA Universitas Sriwijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.26554/sti.2021.6.4.267-272

Abstract

Tropical trees are a source of secondary metabolite compounds that have various biological activities that can help human life both for industrial and pharmaceutical needs. One of the secondary metabolites is polyisoprenoid. This study aims to identify and analyze polyisoprenoid compounds quantitatively from tropical fruit trees at the Universitas Sumatera Utara. Nine samples of tropical fruit were obtained, namely: Psidium guajava, Tamarindus indica, Manilkara kauki, Morinda citrifolia, Mangifera indica, Artocarpus communis, Artocarpus heterophyllus, Gmelina arborea, and Syzygium aqueum. Each sample was extracted and isolated the polyisoprenoid alcohol, then analyzed using two-dimensional thin-layer chromatography. The polyisoprenoid in fruit samples found at the Universitas Sumatera Utara was a type II and III polyisoprenoid compound. The total lipid values ranged from 48.7 mg/g dw to 262.9 mg/g dw, polyisoprenoids ranged from 1.2 mg/g dw to 9.5 mg/g dw, and polyprenols ranged from 0.5 mg/g dw to 5.7 mg/g dw. Carbon chain length and dolichol polyprenol lengths of each fruit were collected (Psidium guajava L.) (C70 C80), (Tamarindus indica L.) (C80 C95), (Manilkara kauki L.) (C80 C95 and C70 C90), (Morinda citrifolia L.) (C75 C100), (Mangifera indica L.) (C80 C90 and C75 C90), (Artocarpus communis) (C75 C95), (Artocarpus heterophyllus) (C70 C75 and C70 C100), (Gmelina arborea Roxb.) (C90 C95), and (Syzygiumaqueum) (C65 C90 and C75 C90).

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